Biomedical subjects

C L Lin

Publications and source records attributed to C L Lin.

At least 127 records · Page 7Linked to original sources

PubMed1996

Modification of DNA topoisomerase I enzymatic activity with phosphotyrosyl protein phosphatase and alkaline phosphatase from the hepatopancreas of the shrimp Penaeus japonicus (Crustacea:Decapoda).

DNA topoisomerase I was partially purified from the hepatopancreas of the shrimp Penaeus japonicus. The specific activity of the final preparation was 7,000,000 units/mg of protein with SV40 viral DNA as substrate. SDD-polyacrylamide gel electrophoresis of the final preparation yielded two major bands of proteins with M(r) 70,000 and M(r) 67,000, as well as less intense bands of proteins with M, 64,000 and M(r) 56,000. Incubation of the partially purified enzyme fraction with rabbit antiserum against human DNA topoisomerase I, allowed all these proteins except that of M(r) 56,000, to be positively reacted. Treatment of the partially purified DNA topoisomerase I with tyrosine kinase p43v-abl resulted in phosphorylation of only the two major subunits. Phosphorylation by tyrosine kinase p43v-abl or dephosphorylation by phosphotyrosyl protein phosphatase resulted in a decrease of the enzymatic activity. The treatment with shrimp alkaline phosphatase abolished the enzymatic activity of the purified DNA topoisomerase I in a dose-dependent manner. Thus, the DNA topoisomerase I was apparently isolated from the hepatopancreas of the shrimp P. japonicus in a phosphorylated form, and this phosphorylation was essential for expression of enzymatic activity in vitro. The activity of DNA topoisomerase I is inhibited by ZnCl2, CuCl2 and Pb(NH3)3 at millimolar concentrations, but less inhibition was observed with CaCl2.

Alkaline Phosphatase↗

PubMed1996

The rectoanal relaxation reflex and continence in repaired anorectal malformations with and without an internal sphincter-saving procedure.

From 1985 to 1994, 27 patients with high- or intermediate type imperforate anus who underwent anorectoplasty were studied for postoperative function, particularly with respect to the rectoanal relaxation reflex and continence. Fourteen of the patients had a rectourogenital fistula and were treated with posterior sagittal anorectoplasty using the fistular end as the neoanus (internal sphincter-saving). Nine patients had a blind rectal pouch and received posterior sagittal anorectoplasty using the trimmed bowel end for reconstruction of the neoanus (incomplete internal sphincter-saving). The other four had Rehbein's mucosa-stripping endorectal pull-through combined with anterior sagittal anorectoplasty (none internal sphincter-saving). A positive rectoanal relaxation reflex was found in 8 of 14 (57.1%), 7 of 9 (77.8%), and 3 of 4 (75%), respectively. It appears that the internal sphincter-saving procedure is not essential for the development of the rectoanal relaxation reflex. Compensation or adaptation most likely contributes to the presence of the rectoanal relaxation reflex, and perhaps to postoperative continence.

Anal Canal↗

PubMed1996

Colitis causes bone loss in rats through suppression of bone formation.

BACKGROUND & AIMS: Idiopathic inflammatory bowel disease (IBD) is associated with bone loss in more than 30% of cases. Nevertheless, the pathogenesis of the bone loss is uncertain. The aim of this study was to investigate the bone loss and underlying mechanisms using an animal model of IBD. METHODS: Severe colitis was induced by intrarectal administration of a hapten, 2,4,6-trinitrobenzenesulfonic acid (TNBS). Severity of IBD was graded macroscopically and histologically. Bone histomorphometry was performed on cancellous bone of the tibiae. RESULTS: A florid transmural colitis was observed 3 weeks after administration of TNBS. In these animals, there was considerable cancellous bone loss of 33% compared with age-matched, pair-fed control animals. This was associated with a marked suppression of the cancellous bone formation rate to < 30% of that in control animals. Thereafter, bone formation rate increased in parallel with healing of colitis. Twelve weeks after TNBS administration, the persistent increase in bone formation rate was associated with return of bone volume to control levels. CONCLUSIONS: The data suggest that bone loss can occur rapidly in colitis and is associated with suppression of bone formation. This study also shows that the bone loss that occurs during TNBS-induced colitis is reversible.

Animals↗

PubMed1996

Isolation and characterization of a novel Deinococcus radiodurans mutant abnormally susceptible to mutation induction by UV, gamma-ray, and mitomycin C.

We isolated and characterized a novel, radiation 'hypermutable' mutant of Deinococcus radiodurans. Compared with the wild-type strain D. radiodurans IR, this mutator strain, designated S101, exhibited sensitivity to UV light, gamma-ray, mitomycin C, and N-methyl-N'-nitro-N-nitrosoguanidine. Spontaneous revertants of S101 that restored wild-type phenotype (non-mutability and resistance to these DNA-damaging agents) were also isolated. Furthermore, the increased susceptibility to DNA-damaging agents and mutability observed in S101 could be mimicked by treating D. radiodurans IR with Mn(II) ions. Our results suggest a putative new pathway of DNA repair in the extremely radioresistant bacterium D. radiodurans.

Antibiotics, Antineoplastic↗

PubMed1996

Prenatal diagnosis of terminal deletion 7q and partial trisomy 3p in fetuses with holoprosencephaly.

Chromosome aberrations, mendelian mutations and exogenous agents can cause holoprosencephaly. Therefore, etiologic evaluation of holoprosencephaly is necessary for obstetricians and genetic counselors, once a prenatal diagnosis of holoprosencephaly has been made. We present four pregnancies in three women in which routine sonographic examinations led to the prenatal diagnosis of holoprosencephaly. Prenatal cytogenetic analysis and fluorescence in situ hybridization demonstrated a 46,XY,del(7)(pter-->q32:) and a 46,XY,der(2)t(2;3)(q37;p21)pat karyotype respectively in two fetuses with cyclopia, and a 46,XX,der(2)t(2;3)(q37;p21)pat and a 46,XX,der(7)t(3;7)(p23;q36) karyotype respectively in two fetuses with premaxillary agenesis. In conclusion, terminal deletion 7q and partial trisomy 3p in holoprosencephalic fetuses indicates that genes contributing to craniofacial development reside in these critical regions. Proper prognostic evaluation in further pregnancies requires expertise in cytogenetics and genetic counseling.

Adult↗

PubMed1996

Continence and rectoanal sphincteric inhibitory reflex after posterior sagittal anorectoplasty.

Rectoanal sphincteric inhibitory reflex and continence were evaluated in 23 patients with high and intermediate imperforate anus who underwent posterior sagittal anorectoplasty from 1985 to 1993. The postoperative anorectal function was followed both manometrically and clinically at regular intervals. The presence of the reflex was positively related to postoperative continence in patients older than 4 years but not in younger patients. Two patients with a rectoprostate fistula after an internal sphincter saving procedure had unsatisfactory results. Seven of nine patients with a blind rectal pouch, whose distal rectal end (where the internal sphincter lies) was partially excised or trimmed during reconstruction, had fair postoperative defecation. The internal sphincter saving procedure is helpful but it does not seem essential for the development of continence. The fact that patients with a negative reflex turned out to have a positive reflex 7 to 33 months after the initial test suggested that the rectum or perirectal tissue had recovered from surgical trauma. Time and age are important factors in clinical evaluation and interpretation of manometric results.

Anal Canal↗

PubMed1995

A de novo satellited short arm of the Y chromosome possibly resulting from an unstable translocation.

A satellited long arm of the Y chromosome (Yqs) is considered a normal variation, whereas the presence of a satellite on the short arm of the Y (Yps) has never been described in the literature. A Yps chromosome could be clinically significant if the translocation resulting in Yps has relocated the testis-determining gene, SRY, to another chromosome. A carrier of such a translocation would therefore be at increased risk for having XX male and XY female offspring. Here we describe the first reported case of de novo Yps present in a phenotypically normal male. This Yps chromosome was positive for C-banding and nucleolus organizer region (NOR) staining and showed a hybridization signal for the beta-satellite sequence. Fluorescence in situ hybridization (FISH) analysis indicated that SRY was retained on the Yps and the translocation breakpoint on Yps was distal to the pseudoautosomal region. At prenatal diagnosis, a normal appearing Y chromosome was found in his son, and thus the satellite on Yps was lost during meiotic Xp-Yp pairing. This Yps chromosome was likely the product of an "unstable" translocation.

Adult↗

PubMed1995

Colon perforation in a patient with hyperimmunoglobulin E (Job's) syndrome.

A Taiwanese boy was diagnosed as having hyperimmunoglobulin E syndrome at the age of 4 years. At age 18 he was admitted to the hospital because of pneumonia in the left lower lobe. Abdominal pain developed 9 days later, and his condition progressed to peritonitis. Colon perforation, 10 cm distal to the ileocecal valve, was found. Double-barrel ileostomy was performed, and reanastomosis was done 1 1/2 months later. Afterward, he was fine, and he had no significant gastrointestinal problems after being discharged. To the author's knowledge, this is the first reported case of hyperimmunoglobulin E syndrome complicated by colon perforation.

Adolescent↗

PubMed1995

Radon concentrations in spa water taken from hot and cold springs in Taiwan.

Spa water samples taken from hot and cold springs throughout Taiwan were analyzed for waterborne radon concentrations using electret ion chambers. The highest radon concentration was detected at Yangmingshan National Park, where it is closed to the action level of 11.0 kBq m-3. Next comes a sea-water hot spring at Green Isle on the east coast of Taiwan. The spa water used by the nearby inhabitants may increase the indoor radon concentration by a factor of two in extreme cases.

Environmental Monitoring↗

PubMed1995

Causes of reduced survival of neonatal pigs by medium-chain triglycerides: blood metabolite and behavioral activity approaches.

Two experiments were conducted to investigate the causes of the failure of orally dosed medium-chain triglycerides (MCT) in improving the survival of neonatal pigs. In Exp. 1, four litters consisting of 24 unsuckled neonatal pigs were either dosed with 6 mL/kg BW.75 of MCT or the dosing process was mimicked by inserting and withdrawing the feeding tube at 10 and 18 h after birth. Blood beta-hydroxybutyrate concentration was increased (P < .06) and the depletion of liver glycogen was reduced (P < .05) by MCT. Plasma octanoate (C8) concentration peaked at 1 h and was minimized at 4 to 8 h after each MCT dosage; decanoate (C10) concentration increased (P < .001) gradually after each dosage. Activity of pigs was decreased (P < .01) by MCT. In Exp. 2, 94 litters consisting of 887 neonatal pigs were dosed with either 6 mL/kg BW.75 of MCT, coconut oil (CO), or saline at 10 to 14 and 20 to 28 h after birth. Milk intake (P < .05) and weight gain were reduced (P < .01) in 1- to 2-d-old pigs dosed with MCT compared with intake and gain of pigs dosed with saline. Mortality of large pigs (> 1 kg) was increased (P < .05) but mortality of small pigs (< 1 kg) was not affected by MCT. Mortality of small pigs was reduced (P < .05) but mortality of large pigs (> 1 kg) was not affected by CO. Standing, walking, and suckling behaviors of pigs were not affected by MCT or CO. Coma was evident in 9.7% of pigs dosed with MCT.(ABSTRACT TRUNCATED AT 250 WORDS)

3-Hydroxybutyric Acid↗

PubMed1995

Yolk sac tumor of unknown origin with intracranial and spinal metastases.

Primary intracranial yolk sac tumor (Endodermal sinus tumor, YST) is quite rare, and most usually involves the pineal gland. This report concerns a rare case of unknown origin of yolk sac tumor with intracranial and spinal metastases. The 6-year-old boy initially manifested symptoms of acute urinary retension and paraparesis. Computed tomography (CT) and magnetic resonance imaging (MRI) revealed an intrathecal tumor spreading below the third lumbar segment, and tumors also appeared in the left temporal area and right cerebellar hemisphere. The pineal region was free of neoplastic involvement and the gonads were normal. The patients underwent operation to remove intracranial and spinal tumors, and postoperative radiotherapy was administered. The histological findings showed metastatic yolk sac tumor. Multiple intracranial and spinal seeding were noticed postoperatively. The patient died of recurrent YST and pneumonia three months after operation. The origin of secondary YST can always be found in specific midline sites. This is a rare case since the primary lesion is unknown.

Brain Neoplasms↗

PubMed1995

[Effects of dihydroxyacetophenone on pulmonary hemodynamics and plasma ANP as well as cAMP/cGMP level in patients with chronic obstructive pulmonary disease].

In order to study the effect of dihydroxyacetophenone (DHAP) on pulmonary hemodynamics and its relationship to plasma ANP as well as cAMP/cGMP level in chronic obstructive pulmonary disease (COPD), 11 COPD patients were examined with the right heart catheterisation, and the plasma ANP and cAMP/cGMP were measured with radioimmunoassay at the same time. The results showed that intravenous given DHAP 640 mg could decrease mean pulmonary arterial pressure, pulmonary vascular resistance and systemic vascular resistance (P < 0.05), but increase the cardiac output from 4.10 +/- 1.08 L/min to 5.13 +/- 1.19 L/min (P > 0.05) and not affect systemic arterial pressure (P > 0.05) as well as blood gas analysis; it also reduce the plasma ANP and cGMP level from 0.73 +/- 0.42 pg/ml to 0.41 +/- 0.33 pg/ml (P < 0.01) and from 9.82 +/- 5.75 pm/ml to 8.01 +/- 4.80 pm/ml (P < 0.05) respectively, but did not affect the plasma cAMP level (P > 0.05). It is suggested that DHAP may relax pulmonary vessels by regulating the ratio of cAMP to cGMP, and the lowering of plasma ANP level might be a secondary reaction. So we consider that DHAP is a fast-acting, safe and potential drug in treating pulmonary arterial hypertension by COPD.

Acetophenones↗

PubMed1995

Simultaneous identification and determination of residual penicillins by use of high-performance liquid chromatography with spectrophotometric or fluorometric detectors.

Using 7 penicillins (amoxicillin, ampicillin, methicillin, penicillin G, oxacillin, cloxacillin, and dicloxacillin), simultaneous and direct determination of residual penicillins in biological samples was carried out by use of bioassay and high-performance liquid chromatography with spectrophotometric or fluorometric detectors. By use of assay medium seeded with penicillin-sensitive Micrococcus luteus (ATCC No. 9341) as a test organism, we were able to detect penicillins even at low concentrations. All penicillins treated with 10 U of penicillinase/ml did not produce inhibition zones by disk testing, even at a concentration of 100 micrograms of penicillin/ml/assay plate. Using a mobile phase of acetonitrile:methanol: 0.01M KH2PO4 (19:11:70, v/v/v; pH, 7.1), standard solutions of the penicillins were separated from each other by use of high-performance liquid chromatography analysis, producing symmetric peaks without tailing, each of which had a characteristic retention time. Simultaneous detection of residual penicillins in bovine serum, kidneys, and liver, for the 5 penicillins for which analysis was possible by use of the UV method, yielded recovery rates from 71.4 to 102.3%; for the 2 amino-penicillins, amoxicillin and ampicillin, which could only be detected by use of the fluorometric method, recovery rate ranged from 72.9 to 103%.

Animals↗

PubMed1995

[Intracranial aneurysm in Taiwan].

We reviewed the epidemiologic and clinical features of ruptured intracranial aneurysms based on the available data in the literature reported in Taiwan. Among 28,763 stroke patients registered by members of the Neurological Society of Taiwan, 600 patients had verified intracranial aneurysms (2.1%), constituting only 34.7% of 1,730 patients with subarachnoid hemorrhage. The male to female ratio was 0.68.1. The mean age was 54.6 +/ 14.3 years in men, and 56.5 +/ 13.8 years in women. Among the 409 patients whose aneurysmal sites were recorded, the aneurysm occurred at the anterior communicating artery in 109 (26.7%), at the posterior communicating artery in 90 (22.0%), at the internal carotid artery in 82 (20.1%), at the middle cerebral artery in 80 (19.6%), at the anterior cerebral artery in 50 (12.2%), at the vertebral-basilar system in 13 (3.2%), and multiple sites in 33 (8.1%). Cerebral angiography was performed in 72.2% of patients and operation was undergone in 57.7%. A randomized follow-up study in 59 patients showed survival rates of 63% for 1 month, 53.3% for 6 months and 43.6% for 1 year. The reported surgical mortality rates ranged from 7.7% to 12.5%. Prognosis was related to the score on the World Federation of Neurological Societies Subarachnoid Hemorrhage Scale. In Taiwan, the number of patients with intracranial aneurysm has been underestimated among who have presented with subarachnoid hemorrhage. The high mortality and morbidity of aneurysm rupture justify an aggressive attempt to establish a prompt and accurate diagnosis.

Adolescent↗

PubMed1995

Digital indocyanine green angiography in chorioretinal diseases.

BACKGROUND: Fluorescein angiography (FA) is important in the diagnosis of chorioretinal diseases; however, it has some limitations. We conducted this study to evaluate whether digital indocyanine green (ICG) angiography can offer enhanced image in chorioretinal diseases. METHODS: Digital indocyanine green angiography with scanning laser ophthalmoscope (SLO) was performed in 314 patients with various chorioretinal diseases. This coupled digital imaging system can offer instant images, process and store data by computer, and give convenient hardcopy generation. RESULTS: The digital ICG angiography provided enhanced image resolution of the choroid compared with FA. The disease categories included choroidal neovascularization (CNV), choroidal tumor, inflammatory choroidal disease, ischemic choroidal disorder, idiopathic central serous chorioretinopathy and retinal macroaneurysm. CONCLUSIONS: ICG angiography is a useful adjunctive diagnostic technique to fluorescein angiography for various chorioretinal diseases. It is especially useful in the diagnosis of occult and recurrent CNV, as well as choroidal tumor and choroiditis. With greater clinical experience, ICG angiography is promising in giving additional clinical information for many other chorioretinal diseases.

Choroid Diseases↗

PubMed1994

Heparin-surface-modified intraocular lens implantation in patients with glaucoma, diabetes, or uveitis.

We investigated the clinical outcome in two groups of patients who had an extracapsular cataract extraction and implantation of a heparin-surface-modified intraocular lens (HSM IOL) (Group 1) or a conventional poly(methyl methacrylate) (PMMA) lens (Group 2). Nineteen patients in Group 1 had bilateral cataract extraction with implantation of an HSM IOL in one eye and a conventional lens in the fellow eye. All patients had glaucoma, diabetes, or uveitis. Over the long term, there was no statistically significant difference between groups in visual acuity, corneal edema, anterior chamber reaction, and amount of posterior synechia formation and IOL deposits. Yet short-term clinical evaluation revealed significantly less reaction in eyes with the HSM IOL than in those with the PMMA lens. In patients with both lens types implanted, early postoperative anterior chamber reaction was less and IOL deposits fewer in the eye with the HSM IOL.

Cataract Extraction↗

PubMed1994

Risks of bloodborne diseases to emergency personnel in traumatic wound management.

High prevalence of viral hepatitis, increasing HIV infection and other bloodborne diseases in Taiwan have made the health care provider exposed to an increased risk of disease transmission unless adequate precautions and protections have been undertaken. Furthermore, emergency personnel must face the patient with limited information, and neither a reliable predictor nor appropriate tools have been found to assist in identifying emergency patients who pose a risk. The Centers for Disease Control (CDC) in the United States thus issued a specific caveat advocating all body fluids should be treated as potentially infectious under uncontrolled emergency circumstances. Unfortunately, in Taiwan, personnel in emergency service practice with limited protection, often without mask and only gloves as the only barrier device used. We tried to determine the risk of facial exposure during traumatic wound management. One hundred and fifteen wounds of 107 patients were enrolled. Most of them were not life-threatening and thus could be managed under more controlled conditions. Standard procedures of wound management were applied and facial exposure was assessed after each wound closure. Positive exposure rate in such controlled conditions remained as high as 46/115 (40%). Exposure rate in uncontrolled conditions should be, therefore, much more significant. Therefore, we should put more emphasis on adequate precaution and protection against bloodborne diseases.

Blood-Borne Pathogens↗

PubMed1993

Specific phosphorylation of membrane proteins of Mr 44,000 and Mr 32,000 by the autophosphorylated insulin receptor from the hepatopancreas of the shrimp Penaeus monodon (Crustacea: Decapoda).

The insulin receptor, purified from the hepatopancreas of the shrimp Penaeus monodon, is a hydrophobic heterodimer of subunits with relative masses (Mr) of 70,000 and 58,000, as estimated by FPLC on Superose 12 and SDS-PAGE. Only the subunit of Mr 70,000 was autophosphorylated after the addition of insulin. The autophosphorylation occurred specifically at Tyr residues, as demonstrated by the specific subsequent dephosphorylation by the phosphotyrosyl protein phosphatase from the hepatopancreas of the shrimp Penaeus monodon. Proteins of Mr 44,000 and Mr 32,000 on the plasma membrane from the hepatopancreas of the shrimp Panaeus monodon were phosphorylated by the autophosphorylated insulin receptor from the shrimp hepatopancreas, but not by that from the human placenta. The detergent, Triton X-100, caused noticeable enhancement of the autophosphorylation of both shrimp and human insulin receptors.

Amino Acid Sequence↗