Biomedical subjects
Publications and source records attributed to C K Lin.
A 5-year-old girl had suffered from infantile spasms since 3 months of age. Cranial computerized tomography revealed agenesis of the corpus callosum. Abnormal ocular fundus features consisted of bilateral disc colobomas and lacunar pigment change in her right eye. The clinical presentations were consistent with Aicardi syndrome. The ophthalmologic manifestations of Aicardi syndrome will be discussed in this paper.
We have reported that many cases of Hb H disease have a complication of iron overload without a history of multiple blood transfusion or prolonged iron therapy. We determined their iron absorption by 59Fe whole body counting in 13 such cases. Also 10 normal subjects were studied as a control group. The results showed a significant increase in iron absorption to 20.3%, in contrast to 6.9% in the normal control. This was further documented by their RBC incorporation (i.e. the percentage of orally administered) 59Fe recovered in the total RBC mass) on day 14 (13.7% vs 6.1%). The degree of ineffective erythropoiesis might not be severe considering their similar 59Fe utilization by RBC (i.e. the percentage of absorbed 59Fe recovered in the RBC) to the normals (86.3% vs. 84.3%).
The ideas discussed above clearly point to increasingly complex and interactive transduction mechanisms for the regulation of the neutrophil. The central challenges to be met include the following: 1. Better assays are needed for the study of physiological parameters such as adherence, aggregation, shape change, and cytoskeletal rearrangements, assays which are not prohibitively complex and expensive while still allowing for more detailed physiological observations. 2. The neutrophil receptors need to be characterized in greater detail at the molecular level. Protein purification, sequencing, and cloning approaches are needed. Given the inherent shortcomings of working with the neutrophil system due to the presence of proteases and the problems of obtaining sufficient amounts of plasma membranes as source material for receptor purification, this is a difficult task. Advances in micropurification and sequencing may alleviate some of the difficulties here. 3. The size and complexity of the G-protein family continue to expand. However, as pointed out earlier, stimulus-responsive enzymes without G-protein-associated regulation, and G-proteins without clearly identified targets, remain. A better definition and description of the G-protein family will be required if cellular regulation is to be understood at the molecular level. In terms of second messengers and their role in cellular regulation, the main questions which remain to be answered concern identification of the precise pathways which are important to cellular regulation. In order to understand the complex cascades of arachidonate metabolism, phospholipid turnover, and calcium homeostasis, it is all the more important that the manner in which second messengers may regulate particular cell functions be better understood. An omission in this review is the role of kinases in cellular regulation. Activation of kinase C (through calcium and diacylglycerol) and kinase A (through cAMP) has been demonstrated. The substrates for these kinases have been described by various investigators. However, relating phosphorylation changes in a particular protein to the activity of the protein, and assignment of activity to particular physiological roles, has not been satisfactorily accomplished and remains a challenge for the future.
The purpose of this survey is to find out whether Hakka group has higher incidence of thalassemia traits in our population. A total of 1,115 healthy employees from a company were screened by complete blood count (CBC) with indices. Those subjects with mean corpuscular volume (MCV) less than 80 fl were further evaluated by hemoglobin electrophoresis and modified hemoglobin H (Hb H) inclusion staining to confirm the diagnosis of beta- and alpha-thalassemia traits, respectively. We evaluated and compared the crude occurrence rates of thalassemia traits in Hakka, non-Hakka, and Taiwanese. Subjects with one or both Hakka parents had higher crude incidence of alpha-thalassemia traits than other groups of subjects, but this phenomenon wasn't found in beta-thalassemia traits.
From May 1974 to March 1989, 48 cases of pregestational diabetes mellitus treated during the third trimester of pregnancy at the Obstetric Clinic of the National Taiwan University Hospital had complete maternal-fetal chart, and were enrolled into this retrospective review. Of these cases, 28 were class B, 13 were class C and seven were class D-R. The maternal complications and perinatal morbidities of each class were reviewed. The mean fasting, postprandial plasma glucose concentrations and the mean excursion of plasma glucose levels were calculated for statistical analysis. Among the maternal complications, urinary tract infections and preterm labor were significantly associated with mean fasting plasma glucose concentrations. Among perinatal morbidities, neonatal respiratory distress and metabolic problems (including neonatal hyperbilirubinemia, symptomatic hypoglycemia, hypocalcemia and polycythemia) were significantly associated with mean plasma fasting glucose concentrations, and perinatal asphyxia was associated with a mean excursion of plasma glucose levels. In view of the paucity of knowledge about the etiology of complications in diabetic pregnancies, it is necessary to conduct a prospective multi-center study with well-characterized morbidities to search for the role of glycemic control in obstetric and perinatal complications.
In a total group of 415 subjects (100 normal controls, 115 with iron deficiency anemia, 100 with the alpha-thalassemia trait, and 100 with the beta-thalassemia trait), the following indexes were analyzed: hemoglobin distribution width, red blood cell distribution width (RDW)-coefficient of variation, and RDW-SD. The hemoglobin distribution width and RDW-coefficient of variation were examined with a laser light scattering system (Technicon H1), whereas the RDW-SD was determined with an impedance autoanalyzer (Sysmex M-2000). All of these parameters helped, to some extent, in the differential diagnosis of microcytic anemia. However, our data suggested a low RDW-SD might provide significantly more value in differentiating thalassemia traits from iron deficiency anemia, as well as from normal controls, while the hemoglobin distribution width gave no help in the differential diagnosis between iron deficiency anemia and the beta-thalassemia trait.
We evaluated 61 patients with two screening tests for alpha-thalassemia traits on the basis of endonuclease gene mapping. Comparing these two methods--the osmotic fragility test of the red cell and modified hemoglobin H inclusion staining for the sensitivity--we found that the latter was much superior to the former with 100% sensitivity in detecting heterozygous alpha-1 thalassemia and it was also specific as a confirmatory test for thalassemia traits. Red cell indices are still the basic screening tool and can be used together with modified Hb H inclusion staining. The osmotic fragility test was not better than the red cell indices and was not confirmatory. Besides the MCV, RBC, and discrimination functions, we found that RBC distribution width-standard deviation (RDW-SD) was consistently low in heterozygous alpha-1 thalassemia but not in heterozygous alpha-2 thalassemia. None of the above tests was shown to be really helpful in screening in the latter situation. We conclude that the modified Hb H inclusion staining is superior to the osmotic fragility test in screening of alpha-1 thalassemia.
Fifty-three patients receiving long-term platelet transfusions were regularly screened for platelet-associated antibodies by a platelet suspension immunofluorescence test (PSIFT) and a lymphocytotoxicity test (LCT). Subsequently, 24 patients became alloimmunized; all of their antibodies were of HLA specificity. Eighty-two single-donor platelet transfusions were given, and the clinical responses were considered satisfactory if the 18-hour corrected count increment was 7.5 x 10(3) per microL or higher. In the meantime, 82 pairs of patient sera and donor lymphocytes were crossmatched. Among 63 crossmatched transfusions, 53 (84%) resulted in a satisfactory increment, with a mean (+/- SEM) of 17.71 +/- 1.96 (x 10(3)/microL), and 10 did not result in a satisfactory increment. The increments after 19 unmatched transfusions and 25 random-donor (uncrossmatched) transfusions were 0.7 +/- 0.3 and 2.39 +/- 0.66, respectively. The difference was not significant (p greater than 0.05). The agreement between the LCT results and clinical response was 88 percent. Retrospectively, the corrected count increments showed no significant differences (p greater than 0.05) among three groups of HLA grading: the increments for A/BU/BX, C/D, and random HLA matches were 22.97 +/- 4.07, 15.1 +/- 1.97, and 14.85 +/- 2.04, respectively. These results suggest that platelet crossmatching by LCT is an effective method for use in alloimmunized patients, especially Chinese patients.
A case of acquired haemophilia A presenting with extensive spontaneous bruising and anaemia is reported. The anaemia was due to myelodysplastic syndrome (FAB: refractory anaemia with ringed sideroblasts). A factor-VII:C-specific inhibitor was also found. Prednisone and pyridoxine were given, and the inhibitor became undetectable after 4 weeks of therapy, but the abnormal ringed sideroblasts still persisted on repeated bone marrow biopsy.
Human granulocyte-macrophage colony-stimulating factor (hGM-CSF) secreted by a hepatoma cell line, HA22T/GVH, was purified and assessed for its effects in vivo on blood leukocytes and bone marrow granulocyte-macrophage progenitor cells (CFU-GM) in ICR mice pretreated with a sublethal dose of cyclophosphamide (cytoxan). The hGM-CSF preparations were natural and had no detectable endotoxin. Five days after the administration of 300 mg/kg cytoxan, severe leukopenia with marked myelopoietic suppression was induced. The cytoxan-treated mice were then injected intraperitoneally with 10,000 units of purified hGM-CSF/mouse daily for three days. Leukopenia was totally abrogated and the leukocyte number greatly increased to a level 2- to 3-fold higher than in GM-CSF-uninjected mice. Differential white cell count showed that the subpopulations of leukocytes responsive to hGM-CSF stimulation were mainly of neutrophils and monocytes, while the lymphocytes remained unaffected. Meanwhile, in the bone marrow, hGM-CSF administration induced an apparent (3-fold) increase in the number of myeloid progenitor cells, CFU-GM. However, the effect in vivo of a single hGM-CSF injection could only maintain for 48 hrs. In addition, the loss in body weight caused by cytoxan was less in the mice with subsequent hGM-CSF than those without CSF. These results suggest that injection of GM-CSF can effectively reconstitute the cytotoxic drug-damaged myelopoiesis without apparent in vivo toxic reaction.
Forty-three patients with myelodysplastic syndrome (MDS) were retrospectively analyzed for its prognostic factors. We evaluated the relationship of the clinical, biochemical, and hematological data, as well as colony-forming unit myeloid (CFU-C) culture, Bournemouth score, modified Bournemouth score, and modified Dutcher score to the prognosis. The median age was 65 years. Eighteen patients had refractory anemia (RA), 4 had refractory anemia with ringed sideroblasts (RARS), 15 had refractory anemia with excess blasts (RAEB), 2 had refractory anemia with excess blasts in transformation (RAEB-t), and 4 had chronic myelomonocytic leukemia (CMMoL). The median survival of all patients was 482 days. The median survival for each subtype was as follows: RA, 628 days; CMMoL, 350 days; RAEB, 240 days; RAEB-t, 90 days. For RARS, no data have yet been obtained, because only one out of 4 patients with RARS has died. We subdivided all patients into two groups: one group included patients with RA or RARS and the other group included patients with RAEB, RAEB-t or CMMoL. The former group had a median survival of 677 days and the latter group 240 days, p = 0.0035. In the former group, 3 out of 22 patients (13.6%) developed acute myeloid leukemia (AML), as compared to 8 out of 21 patients (38.1%) in the latter group, p = 0.0661. Twenty-five of the 43 patients died: 10 from AML and 15 from infection and/or bleeding.(ABSTRACT TRUNCATED AT 250 WORDS)
Eleven cases of severe type hemophiliacs who had received long-term factor VIII injections were tested for the serological markers of human immunodeficiency virus (HIV), hepatitis B virus and hepatitis C virus (HCV). The period of factor VIII concentrate injections ranged from 2 to 32 years. The seropositive rates of HIV and HCV were 9/11(82%) and 11/11(100%), respectively. The seropositive rate of hepatitis B surface antigen was only 1/11(9%), while the seropositive rates of antibody to hepatitis B core antigen and antibody to hepatitis B surface antigen were 9/11(82%) and 7/11(64%), respectively, Although the patients had no symptoms related to acquired immunodeficiency syndrome, they were noted to have inverted helper/suppressor T-lymphocyte ratio, suggesting that hemophiliacs with long-term factor VIII injections have a high incidence of HIV and HCV infection, with immunological aberration.
The aim of this study was to determine the crude prevalence of alpha-thalassemia traits in Taiwan. A total of 1435 healthy employees from a statewide company were randomly screened by complete blood count determination with indices. Subjects with mean corpuscular volume less than 80 fl were analyzed by hemoglobin electrophoresis on cellulose acetate to exclude beta-thalassemia and with serum ferritin to exclude iron deficiency. Modified hemoglobin H inclusion staining was performed to confirm the diagnosis of alpha-thalassemia traits, and DNA probe studies were used to confirm the validity of this test. The overall prevalence rate of alpha-thalassemia trait was 3.4% (48 out of 1435). In persons of mainland Chinese origin, prevalence was 0.4%, and among persons of Taiwanese origin, it was 4.0% (47 out of 1171). We conclude that alpha-thalassemia traits are common genetic disorders in Taiwan and that antenatal screening is advised to reduce the frequency of occurrence of hemoglobin Bart's hydrops fetalis. The methods we used proved to be reliable and inexpensive.
For the purpose to clarifying the biologically active substance of B. pertussis, we prepared the filamentous hemagglutinin (FHA) from culture supernatant of the strain Tohama phase I and purified it through chromatography columns of hydroxylapatite, fetuin-Sepharose 4B and Sepharose CL 6B. There are several bands appeared in the polyacrylamide gel after SDS-PAGE, especially between 98 kD and 210 kD. The amount of 210 kD component is not proportional to hemagglutination (HA) activity of FHA among five different lots. Irons et al. reported that FHA preparation degraded the 220 kD and 210 kD polypeptides during the storage would be reduced the specific HA activity. Our result pointed out that the HA activity of purified Foffdid not relate to 210 kD component only. For the quality control of FHA purity in the B. pertussis acellular vaccine, we suggest that it would be necessary to test both HA titer and SDS-PAGE results.
Various concentrations of 1,25-dihydroxyvitamin D3 (vit D3; 10(-9)-10(-7) M) and recombinant human tumor necrosis factor alpha (rTNF-alpha; 60-960 U/ml) were used to induce growth inhibition and differentiation of the human promyelocytic leukemia cell line HL-60 based on growth kinetics, colony formation, morphological analysis, nonspecific esterase (NSE) activity, surface antigen expression, and cytokine release. Both vit D3 (10(-8)-10(-7) M) and rTNF-alpha (60-960 U/ml) were antiproliferative against the HL-60 cells, and a cooperative effect was noted when the two inducers were used in combination. After 5 days of incubation, vit D3 induced the HL-60 cells to differentiate into monocytes/macrophages, resulting in the formation of 3.0% +/- 0.4%, 18% +/- 2.0%, and 43% +/- 3.8% of morphologically mature cells at 10(-9), 10(-8), and 10(-7) M, respectively. The induced cells were NSE positive and expressed monocyte-associated antigens (EBM11, CD11b, and HLA-DR). Conversely, rTNF-alpha (60-960 U/ml) was unable to trigger the HL-60 cells to differentiate. However, rTNF-alpha could apparently increase the proportion of the morphologically mature and NSE-/antigen-positive cells when used in combination with vit D3 (10(-9)-10(-8) M). Following differentiation induction, HL-60 cells from vit D3-treated HL-60 cultures acquired the ability to secrete certain monokines, including interleukin 1 beta (IL-1 beta), prostaglandin E2 (PGE2), and granulocyte-macrophage colony-stimulating factor (GM-CSF), and adding rTNF-alpha in addition to vit D3 invariably increased the production of IL-1 beta and PGE2.
A homemade corneal marker was contrived from a Pharmacia Superblade disposable corneal trephine by cutting away one arm of the trephine and then bending the single remaining arm to an angle of 45 degrees to the handle. The radii of the trephines ranged from 6.5mm to 8.5mm, at successive increments of 0.25mm. In optical corneal grafts, this marker can be used to pinpoint the center of the cornea, thus providing more accurate centralization of the area to be grafted. In therapeutic corneal grafts, the marker provides a more accurate determination of the most suitable area to be grafted. Unnecessary removal of healthy tissue or incomplete removal of diseased tissue are thus avoided. This marker is made easily and at no additional expense, and show itself to be a useful instrument to accurately determine the graft area in corneal surgery.
Macrophage-derived granulomonopoietic enhancing activity (GM-EA) is a novel mediator that amplifies colony formation of myeloid progenitor cells (CFU-GM) in conjunction with colony-stimulating factors (CSFs), and is distinct from other hematopoietic synergizing factors such as interleukin (IL)-1, IL-4, and IL-6. In the present study, we try to ascertain whether or not there is a GM-EA-specific responsive myeloid progenitor cell population. Human bone marrow cells deleted of adherent cells and T lymphocytes were separated by velocity sedimentation into three subpopulations with respective sedimentation rates (millimeters per hour) of 7.4 +/- 0.4, 6.0 +/- 0.6, and 4.7 +/- 0.3. These subpopulations corresponded to the day 7 CFU-GM, day 14 CFU-GM, and the earlier myeloid progenitor cells, pre-CFU-GM, respectively. Pre-CFU-GM failed to respond to the colony-inducing effect of GM-CSF but could be stimulated by GM-EA alone to generate small clusters (5 to 25 cells) in soft agar after 14 days of incubation. Correspondingly, suspension preculture of the fractionated bone marrow cells also showed that only the progenitor cells with low sedimentation rate (4.7 mm/h) could be activated by GM-EA to generate CFU-GM. Taken together, our results suggest that the specific target cell of GM-EA is the pre-CFU-GM, and that GM-EA acts on these cells as a growth/maturation factor, but on the day 7 and day 14 CFU-GM as a synergistic growth factor.
The melC operon of Streptomyces antibioticus contains two genes, melC1 and melC2, necessary for the production of melanin pigment. We transferred the coding sequence of melC1 and melC2 to Escherichia coli plasmid pMTL23 such that its transcription was under the control of the lac promoter and melC1 was translationally fused to the lacZ alpha fragment. E. coli cultures containing this plasmid, pIF413, produced melanin after overnight incubation on 2YT agar supplemented with 0.1 mM CuCl2, 0.36 mM IPTG (or 0.2% lactose), and 2 mM tyrosine. Erwina carotovora could also be transformed by pIF413 to produce melanin. Two shuttle vectors were constructed: pLUS415 for E. coli and Streptomyces, and pLAF413 for E. coli and Xanthomonas campestris. These vectors confer melanin pigmentation in all the hosts that harbor them. The melC sequence provides the vectors with a convenient cloning marker for insertional or replacement inactivation.