Biomedical subjects
Publications and source records attributed to J N Lin.
In this article we will outline several biosensor applications which may fill existing technology gaps in the area of environmental monitoring. The requirements for these environmental biosensors, as well as difficulties in commercialization, are also addressed.
To assess the efficacy of Kasai operation for biliary atresia, 60 cases during a 14-year period (1976 to 1989) at this institution were reviewed. Thirty-four (56.7%) underwent operation within 90 days of life, 11 (18.3%) between 90 and 120 days and 15 (25.0%) beyond 120 days. Fifty-six underwent hepaticoportojejunostomy and 4 underwent hepaticoportocholecystostomy. Follow-up was 1 to 14 years (mean, 7.2 years). The postoperative follow-up of these 60 patients was categorized into five groups: group A (16 patients, 26.7%) was characterized by survival greater than 3 years and without jaundice; group B (3 patients, 5.0%) was defined as survival greater than 3 years, but with jaundice; group C (11 patients, 18.3%) was defined by survival but follow-up less than 3 years, (this group was further divided into C1 [7 patients, 11.7%] if anicteric and C2 [4 patients, 6.7%] if icteric); group D (2 patients, 3.3%) was patients who underwent liver transplantation; and group E (28 patients, 46.7%) was the group of patients who died at time of review. Group A and group C1 were interpreted as success after Kasai operation; hence, the potential success rate in this series was 38.3% (23 patients). They were long-term survivers, and most of them performed normal activities appropriate for their ages. We conclude that approximately one third of patients with biliary atresia would benefit from or be cured by this operation, which should be the first attempt in the treatment of this disease entity.
Localized plasma cell type Castleman's disease (CD) is an unusual pathologic entity. It is frequently associated with clinical and laboratory characteristics and rarely occurs in children. Total surgical excision results in cure in all aspects. To make early diagnosis of mesenteric CD is not easy, especially for children. An 11-year-old Taiwanese boy was recently evaluated for anemia and delayed growth. His clinical findings included a syndrome of severe hypochromic microcytic anemia, neutropenia, thrombocytosis, hypoferremia, hypergammaglobulinemia, and growth failure. Radiological examinations (abdominal ultrasound, small intestinal series, and computerized tomography) identified hepatosplenomegaly, nephromegaly, and huge masses in the middle abdomen with precaval, celiac, and paraaortic lymph nodal enlargement. However, detailed physical examination failed to detect a mass. At laparotomy a double-fist-sized confluent mass was found arising from the mesenteric root. Most masses were discrete and were excised individually. The pathologic diagnosis was plasma-cell type angiofollicular lymph node hyperplasia (Castleman's disease). Seven weeks after surgery, he had an episode of acute hepatitis B. Postoperatively, he exhibited a dramatic growth spurt; the hemoglobin, red blood cell indices, serum iron, and immunoglobulins returned to normal in 2 months. Neutropenia, which has not been previously related to mesenteric CD, was an unexpected finding in our case; however, it resolved spontaneously 3 months after the surgery, suggesting its causal relationship with the tumor.
Neck sinuses, cysts or fistulae arising from the third branchial apparatus, have seldom been reported. Between 1979 and 1989, 16 cases were diagnosed as persistent third branchial apparatus based on a fistula open or in proximity to the pyriform sinus. There were 8 boys and 8 girls whose ages ranged from newborn to 13 years. Esophagogram was performed in 6; 4 showed a fistula tract leading to the pyriform sinus. Others were demonstrated at surgery. The main presentations were suppurative thyroiditis (5), lateral neck fistula (5), cyst (3), mass (1), abscess (1), and esophageal stricture (1). This was interpreted as a spectrum of disease that in the newborn may present as a cyst, and later in childhood as a fistula in the lower neck or recurrent suppurative thyroiditis if the fistula ends in the thyroid gland. It is imperative to search for this internal communication to the pyriform sinus to make a correct diagnosis and to avoid development of esophagocutaneous fistula postoperatively. With more awareness of this disease entity, the noted incidence should increase.
Spatially-resolved detection of antibody-antigen reactions at the solid/liquid interface was investigated by total internal reflection excited fluorescence from large area flat surfaces. Anti-HSA immunoglobulin G (IgG) antibody was immobilized at four spatially distinct spots. Binding of fluorescein-labeled human serum albumin (HSA) from the solution to immobilized antibody was detected by a cooled charge-coupled device (CCD) as a charge in the fluorescence intensity. A two-dimensional representation of the fluorescence was obtained during the binding reaction time of 25 mins. The contributions from bound and free antigen to the total signal were evaluated. The influence of the scattered excitation light and the normalization of fluorescence signal with respect to the two-dimensional incident light intensity distribution are discussed.
Phytobezoars are composed of fruit or vegetable matter, including seeds, nuts, and pits, and are the most common type of bezoar associated with gastrointestinal obstruction. Eleven gastrointestinal phytobezoar in children (less than 15 years old) seen within a period of 8 years (1981-1988) were analysed. Six were boys and 5 were girls. On history, 6 patients developed symptoms after ingestion of persimmon. All cases except one occurred in late fall and winter. In 8 patients, phytobezoar was found in a single location with 5 in the ileum and 3 in the jejunum. Multiple locations were found in 3 patients. Emergency laparotomy was performed on all cases who had typical mechanical intestinal obstruction. Treatment consisted of fragmentation of bezoar with pushing toward the cecum in 9 patients, combined with gastrotomy in 3 patients, and enterotomy in 2 patients. Because the persimmon ingestion is the most common cause of bezoar formation, a careful dietary history will usually suggest the diagnosis preoperatively. All the gastrointestinal tract should be thoroughly examined intraoperatively, especially the stomach and terminal ileum, to prevent another intestinal obstruction caused by an undiscovered phytobezoar.
Immobilization of biomolecules to solid phase materials has been widely used in many areas (e.g., purification, analytical chemistry, and catalysis). The interfacial properties of immobilized antibodies on pretreated silica and hydrogel surfaces were explored by comparing native and modified antibodies with respect to their surface activity. The antibody was modified by exposing it to a low pH solution prior to immobilization. Both physical adsorption and covalent immobilization methods were studied. It was found that the surface activity of the modified antibody is higher than that of the native antibody on two silica surfaces. The results of this study demonstrate that the adsorption properties of the antibodies play an important role in their covalent immobilization on certain types of solid supports.
Between January 1983 and December 1986, 35 Children with blunt hepatic injury were treated in Chang Gung Memorial Hospital. After vigorous resuscitation, 10 Patients required emergency laparotomies: 9 for massive bleeding, and 1 for associated bowel injury. Exploratory surgery was necessary 5 days after the initial resuscitation in one patient due to rebleeding. The remaining 24 patients who responded well to resuscitations were managed nonoperatively. Imaging examinations (ultrasound, radioisotope scan or computerized tomography scan) provided the diagnosis of liver trauma in all. The hospital courses in all cases were uneventful and there were no complications. In every patient follow-up imaging examinations showed complete resolution of the lesions. We conclude that nonoperative management of selected patients with blunt hepatic trauma is reasonable. With the help of serial imaging examinations, this conservative approach is safe and practical.
The diagnosis of ventral abdominal wall defect can now be made prior to birth. With this diagnosis, the family can make decisions and a planned optimal management can lead to a successful outcome. There were 31 cases of ventral wall defect identified at Chang Gung Memorial Hospital (CGMH) from January 1979 through March 1988. Twenty of them were classified as gastroschisis; among them, 17 (85%) were born in outside clinics and none of them had associated anomalies. In contrast, among 11 cases of omphalocele, there was a lower frequency of transferred cases (27% vs 85%), and 4 cases had additional defects, including two multiple anomalies and two bladder exstrophies. There were no significant differences between gastroschisis and omphalocele in the mortality rate (30% vs 36%), in the incidence of intrauterine growth retardation (IUGR) (30% vs 27%) and in the Cesarean section rate (15% vs 18%). All 4 cases of prematurity (less than 36 weeks of gestational age) expired after delivery and 2 of these had body weights of less than 1500 g. Three out of 5 cases delivered by Cesarean section expired; the mortality (60%) was higher than that of vaginal delivery (28%). All 3 cases were gastroschisis, 2 of them were transferred from outside clinics and all expired due to sepsis. The diagnosis of ventral wall defect should be made prenatally, with obstetric ultrasonography, maternal serum alpha-fetoprotein screening and fetal karyotyping. Therefore, fetal transport in utero to a referral center and optimal perinatal care for those fetuses with potentially correctable lesions can be well planned.
An antigen-binding fragment (Fab) from a murine monoclonal antibody (4-4-20) with high affinity for fluorescein was cocrystallized with ligand in polyethylene glycol (PEG) and 2-methyl-2,4-pentanediol (MPD) in forms suitable for X-ray analyses. In MPD the affinity of the intact antibody for fluorescein was 300 times lower than the value (3.4 x 10(10) M-1) obtained in aqueous buffers. This decreased affinity was manifested by the partial release of bound fluorescein when MPD was added to solutions of liganded Fab during crystallization trials. In PEG, the ligand remained firmly bound to the protein. The liganded Fab crystallized in the monoclinic space group P2(1) in PEG, with a = 58.6, b = 97.2, c = 44.5 A and beta = 95.2 degrees. In MPD the space group was triclinic P1, with a = 58.3, b = 43.4, c = 42.3 A, alpha = 83.9 degrees, beta = 87.6 degrees, and gamma = 84.5 degrees. X-ray diffraction data were collected for both forms to 2.5-A resolution. Surprisingly, the triclinic form of the liganed antifluorescyl Fab had the same space group, closely similar cell dimensions, and practically the same orientation in the unit cell as an unliganded Fab (BV04-01) with activity against single-stranded DNA.
The assessment of blood damage and of the activation of the coagulation, complement and/or inflammatory systems by cardiovascular and extracorporeal devices is difficult at best. Immunoassay methods are now available for the measurement of many of the proteins, enzymes and peptides involved in coagulation, thrombosis, complement and inflammation. We present a long-range project and plan to develop an array of remote, on-line, semicontinuous immunosensors for selected coagulation proteins, based on fluoroimmunoassay principles. The free/bound separation step is performed optically. Excitation of fluorescence is performed via an evanescent wave produced by total internal reflection and waveguide optics. Fluorescence emission is collected only in the near field. Means to deliver fluorescently-labelled reagent and to modify the antigen-antibody binding constant are presented and discussed. The results of non-specific binding, plasma-blood fluorescence, and blood compatibility are also discussed.
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The development of biliary sludge, in the absence of anastomotic obstruction in the common bile duct, has become a very rare complication following orthotopic liver transplantation since the adoption of modern techniques of biliary reconstruction and routine biliary flushing before cold preservation. We describe the successful treatment of this serious complication in an 18-year-old woman whose biliary sludge aggregated into firm casts occupying the extrahepatic and intrahepatic bile ducts causing obstruction and cholangitis necessitating operative intervention followed by interventional radiological approaches to treat the intrahepatic bile duct strictures. Postoperative choledochofiberscopy was also used to remove the retained biliary casts. The pathogenesis of biliary sludge appeared to be multifactorial, but cold ischemic damage to the bile duct wall seemed to play an important role in this case.
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Explore the source record for details and available documents.
Explore the source record for details and available documents.
Explore the source record for details and available documents.
Explore the source record for details and available documents.