Search PubMed⌕ Search

Biomedical subjects

J D Lee

Publications and source records attributed to J D Lee.

At least 127 records · Page 7Linked to original sources

Single photon emission computed tomography-EEG relations in temporal lobe epilepsy.

The role of single photon emission computed tomography (SPECT) as an independent confirmation test in presurgical evaluation of medically intractable temporal lobe epilepsy has not been critically investigated. Because spreading ictal discharges may cause a concomitant increase of cerebral blood flow in remote cerebral regions, a careful analysis of peri-injection EEG patterns and their relation to ictal SPECT may be important in evaluating the reliability of ictal SPECT. Both interictal and ictal EEG and SPECT were reviewed in 19 patients with temporal lobe epilepsy who achieved a successful seizure outcome after surgery. Patients were divided into unitemporal and bitemporal groups according to the lateralization of interictal epileptiform discharges (IED). Ictal EEG features were classified into lateralized and nonlateralized groups. The concordance between SPECT and EEG lateralizations was examined in each patient and correlated to the documented epileptogenic temporal lobe. Interictal SPECT correctly lateralized in eight of nine patients with unitemporal IED and in five of 10 patients with bitemporal IED. Ictal SPECT was highly concordant with the peri-injection ictal EEG but correctly lateralized the epileptogenic region in only 11 of 19 patients. When both pre- and postinjection EEG epochs lateralized ipsilaterally, all ictal SPECT images showed concordant lateralization. If pre- and postinjection EEG epochs were either different in lateralization or nonlateralization, ictal SPECT images often showed complex patterns of cerebral perfusion with a high incidence of false lateralization. Interictal SPECT was more sensitive and reliable in patients with unitemporal IED than in patients with bitemporal IEDs. Ictal SPECT was closely related with peri-injection EEG epochs but with frequent false lateralization. The role of ictal SPECT as an independent confirmation test in presurgical evaluation should be reappraised.

Adolescent↗

Poorly differentiated ("insular") carcinoma of the thyroid gland--two cases report.

Poorly differentiated ("insular") carcinoma of the thyroid shares insular, trabecular, and solid histological patterns that are different from those of papillary, follicular, medullary, and anaplastic varieties. This tumor is situated morphologically and biologically in the intermediate position between the well differentiated (papillary and follicular) and the totally undifferentiated (anaplastic) thyroid tumors. We report two cases of insular carcinoma of the thyroid, occurring in 39-year-old and 52-year-old women. Grossly, these cases showed a lobulated mass with fibrous septa. The histologic finding showed characteristic "insular" growth pattern with focal follicular or papillary areas. Thyroglobulin was demonstrated within cytoplasmic paranuclear vacuoles of the neoplastic cells. Calcitonin and amyloid were not demonstrated. The aspiration cytology showed high cellularity, low grade of atypia, presence of clusters, nests, and trabeculae of cells with poorly outlined cytoplasm. The ultrastructural finding showed primordial cells having cytoplasmic organelles such as rough endoplasmic reticulum, mitochondria, and free ribosomes. We believe that its separation from other types of thyroid carcinoma will lead to a more accurate estimate of its biologic behavior and a more appropriate therapeutic approach.

Adenocarcinoma, Follicular↗

Lymphoepithelial carcinoma of the submandibular gland--a case report.

A case of lymphoepithelial carcinoma occurring in the left submandibular salivary gland is presented. Histologic features of this rare malignancy are described in detail. This unusual carcinoma has been described frequently in Eskimos and is usually located in the parotid gland. The raised serum IgG to Epstein-Barr virus capsid antigen suggests a causal relationship between Epstein-Barr virus and this type of salivary gland carcinoma.

Adolescent↗

Pleomorphic adenoma of the trachea.

A case of salivary gland type pleomorphic adenoma of the trachea in a 48-year-old woman is presented. Pleomorphic adenoma is extremely rare in the trachea. The behavior of this tumor in the trachea appears to be similar to its counterpart in other sites and distinctly different from the more frequently encountered epithelial tumors.

Adenoma, Pleomorphic↗

Radionuclide therapy of skin cancers and Bowen's disease using a specially designed skin patch.

UNLABELLED: Skin cancer is the most common malignancy in humans. Therapeutic modalities for skin cancer are local destruction, radiotherapy and surgery. External radiation therapy leads to good results, however, generally 5-6 wk of treatment is needed to deliver optimal radiation dose to tumors. In this study, a beta-emitting radionuclide, 166Ho, impregnated in a specially designed patch, was used on superficial skin cancers and Bowen's disease for local irradiation. METHODS: Ten mice with chemically induced skin tumors were studied. Five-millimeter size patches containing 22.2-72.15 MBq (0.6-1.95 mCi) 166Ho were applied to the tumor surface for 1-2 hr. In a human trial, patients with squamous-cell carcinoma (n = 3), basal cell carcinoma (n = 1) and Bowen's disease (n = 1) were treated with patches containing 273.8-999 MBq (7.4-27 mCi) of 166Ho for 30 min to 1 hr. Pathologic examination was performed 4-7 wk after treatment in an animal model. Skin biopsy was performed 8 wk post-treatment in four patients. RESULTS: Tumor destruction was seen 1 wk post-treatment, however, radiation dermatitis or ulceration developed at the site of radionuclide application. Those reactions healed gradually with fibrosis or epithelialization, which was confirmed pathologically. No significant adverse reaction to radiation except subcutaneous fibrosis was found. CONCLUSION: Superficial skin tumors could be successfully treated by topical application of beta-emitting radionuclides.

Adult↗

Obstetrical hysterectomy and placenta previa/accreta: three bladder injury case reports.

Pregnancies complicated with placenta previa and a history of cesarean section are well known to be at increased risk for placenta accreta. Bladder injury is occasionally encountered in these patients during operation. From January 1992 to December 1995, 25 obstetrical hysterectomy were performed at Chang Gung Memorial Hospital, Linkou Medical Center. Of these 25 patients three had bladder injury. Ultrasonography is a unique way to screen and detect prenatally the abnormal placentation and intraplacental lacunae. Color Doppler ultrasonic scanning further discloses that the lacunae are mainly venous spaces. Elevated mid-trimester maternal serum x-fetoprotein (MSAFP) frequently leads to a suspicion of the abnormal placentation, and magnetic resonance imaging (MRI) can clearly identify the placenta accreta/increta. Uncontrollable bleeding frequently occurs in these patients during cesarean section, warranting emergency hysterectomy. Emergency obstetrical hysterectomy should be decided upon and performed by an experienced obstetrician. Massive hemorrhage and bladder injury are the major complications encountered in such operations. We review the literature and propose a protocol of management. As the incidence of cesarean section continues to rise world-wide, the problem of placenta previa/accreta is likely to become more common. Obstetricians should be ready to face the late sequelae of today's decision for cesarean section.

Adult↗

Humoral immune responses in mice infected with gamma-irradiated third-stage larvae of Angiostrongylus cantonensis.

Humoral immune responses in C57BL/6 strain mice infected with 1.0 kGy gamma-irradiated third-stage larvae (L3) and with non-gamma-irradiated L3 of Angiostrongylus cantonensis were assessed in this study. The young-adult worm (L5) antigen-specific antibodies in sera of both groups of mice elevated gradually and reached a peak in the third week after infection. The IgM antibodies of mice 1-week after infection with gamma-irradiated L3 and with non-gamma-irradiated L3 recognized several L5 antigens of the same molecular weight. However, only partially identical profiles were observed in the reaction of L5 antigens with IgM and IgG antibodies from mice 3 weeks after infection with gamma-irradiated L3 and with non-gamma-irradiated L3 respectively by western blot analysis. With regard to antibody-dependent cell-mediated cytotoxicity, antibodies from 3-week infected mice significantly increased the adherence of mouse eosinophils and neutrophils to L3 of A. cantonensis. The immunoresponses of splenic cells from mice in the third week of infection to sheep red blood cells were suppressed because the number of plaque forming cells obviously decreased more than the uninfected control.

Animals↗

Pregnancy after intracytoplasmic injection of immotile sperm. A case report.

BACKGROUND: With the advent of intracytoplasmic sperm injection (ICSI), fertilization and pregnancy have been reported in complete asthenozoospermia. The major problem with the use of immotile sperm for ICSI has been differentiating between live and dead sperm. We successfully selected live sperms with the hypoosmotic swelling test, and a twin pregnancy resulted after intracytoplasmic injection of completely immotile sperm. CASE: A 32-year-old woman and her 36-year-old husband had had primary infertility for four years. Evaluation of the couple showed complete asthenozoospermia of the husband. Ovulation in the wife was successfully stimulated with clomiphene citrate, follicle-stimulating hormone and human menopausal gonadotropin. We selected the viable sperm with the hypoosmotic swelling test. ICSI was then performed. After assisted hatching, we transferred four embryos on the third day after oocyte retrieval. Intrauterine twin pregnancy was confirmed by ultrasonography four weeks later. The healthy infants, free of anomalies, were born on the 36th gestational week. CONCLUSION: The hypoosmotic swelling test is a simple method of selecting immotile and viable sperm for use in ICSI.

Adult↗

Recovery of perfusion, glucose utilization and fatty acid utilization in stunned myocardium.

We describe the clinical features and results of cardiac catheterization, PET ([13N]ammonia, 18F-fluorodeoxyglucose (FDG)) and SPECT [123I-labeled 15-(p-iodophenyl)-3-R,S-methylpentadecanoic acid (BMIPP)], in a patient with acute myocardial infarction successfully treated with intracoronary thrombolytic therapy. We compared the clinical and electrocardiographic changes with the myocardial glucose and fatty acid metabolism in stunned myocardium over a period of several months. The patient we studied illustrates the features of stunned myocardium. In the subacute phase, there was a concordant depression of myocardial [13N]ammonia and FDG uptake, and the metabolic abnormalities persisted even after regional wall motion at rest had returned to normal. The electrocardiographic recovery of deep negative T waves appeared to be related to the metabolic recovery in regions of stunned myocardium in this patient.

Ammonia↗

Purification and molecular cloning of an inducible gram-negative bacteria-binding protein from the silkworm, Bombyx mori.

A 50-kDa hemolymph protein, having strong affinity to the cell wall of Gram(-) bacteria, was purified from the hemolymph of the silkworm, Bombyx mori. The cDNA encoding this Gram(-) bacteria-binding protein (GNBP) was isolated from an immunized silkworm fat body cDNA library and sequenced. Comparison of the deduced amino acid sequence with known sequences revealed that GNBP contained a region displaying significant homology to the putative catalytic region of a group of bacterial beta-1,3 glucanases and beta-1,3-1,4 glucanases. Silkworm GNBP was also shown to have amino acid sequence similarity to the vertebrate lipopolysaccharide receptor CD14 and was recognized specifically by a polygonal anti-CD14 antibody. Northern blot analysis showed that GNBP was constitutively expressed in fat body, as well as in cuticular epithelial cells of naive silkworms. Intense transcription was, however, rapidly induced following a cuticular or hemoceolien bacterial challenge. An mRNA that hybridized with GNBP cDNA was also found in the l(2)mbn immunocompetent Drosophila cell line. These observations suggest that GNBP is an inducible acute phase protein implicated in the immune response of the silkworm and perhaps other insects.

Acute-Phase Proteins↗

Big mitogen-activated protein kinase 1 (BMK1) is a redox-sensitive kinase.

Mitogen-activated protein (MAP) kinases are a multigene family activated by many extracellular stimuli. There are three groups of MAP kinases based on their dual phosphorylation motifs, TEY, TPY, and TGY, which are termed extracellular signal-regulated protein kinases (ERK1/2), c-Jun N-terminal kinases, and p38, respectively. A new MAP kinase family member termed Big MAP kinase 1 (BMK1) or ERK5 was recently cloned. BMK1 has a TEY sequence similar to ERK1/2 but has unique COOH-terminal and loop-12 domains. To define BMK1 regulation, its activation in cultured rat vascular smooth muscle cells was characterized. Angiotensin II, phorbol ester, platelet-derived growth factor, and tumor necrosis factor-alpha were the strongest stimuli for ERK1/2 but were weak activators of BMK1. In contrast, H2O2 caused concentration-dependent activation of BMK1 but not ERK1/2. Sorbitol activated both BMK1 and ERK1/2. BMK1 activation by H2O2 was calcium-dependent and appeared ubiquitous as shown by stimulation in human skin fibroblasts, human vascular smooth muscle cells, and human umbilical vein endothelial cells. These findings demonstrate that activation of BMK1 is different from ERK1/2 and suggest an important role for BMK1 as a redox-sensitive kinase.

Amino Acid Sequence↗

Characterization of the structure and function of a novel MAP kinase kinase (MKK6).

Mitogen-activated protein (MAP) kinases require dual phosphorylation on threonine and tyrosine residues in order to gain enzymatic activity. This activation is carried out by a family of enzymes known as MAP kinase kinases (MKKs or MEKs). It appears that there are at least four subgroups in this family; MEK1/MEK2 subgroup that activates ERK1/ERK2, MEK5 that activates ERK5/BMK1, MKK3 that activates p38, and MKK4 that activates p38 and Jun kinase. Here we describe the characteristics of a new MKK termed MKK6. The clones we isolated encode two splice isoforms of human MKK6 comprised of 278 and 334 amino acids, respectively, and one murine MKK6 with 237 amino acids. Sequence information derived from cDNA cloning indicated that MKK6 is most closely related to MKK3. The functional data revealed from co-transfection assays suggests that MKK6, like MKK3, selectively phosphorylates p38. Unlike the previously described MKKs (or MEKs), MKK6 exists in a variety of alternatively spliced isoforms with distinct patterns of tissue expression. This suggests novel mechanisms regulating activation and/or function of various forms of MKK6.

Amino Acid Sequence↗

Extent of sperm chromatin hydration determined by atomic force microscopy.

Volume measurements were performed on intact bull and mouse sperm heads and amembranous sperm nuclei, both in the fully hydrated (fluid cell) and dehydrated (air-dried on glass coverslips) states by atomic force microscopy (AFM). Data were obtained by analyzing a small population of cells/nuclei, as well as by performing repeated measurements on single cells imaged following the addition of increasing concentrations of propanol. Results show that the volume of fully hydrated, intact sperm heads and amembranous sperm chromatin particles are at least twice the volume of their air-dried counterparts. Dehydration occurs rapidly in air, and the reduction in volume of chromatin induced by water loss appears to be completely reversible. These studies demonstrate that both mouse and bull sperm chromatin are extensively hydrated in the native state, and are not as compact as previous studies have suggested.

1-Propanol↗

Evaluation of cardiac sympathetic neuronal integrity in diabetic patients using iodine-123 metaiodobenzylguanidine.

Autonomic dysfunction is associated with increased mortality in diabetic patients. To evaluate the cardiac autonomic dysfunction in these patients, a prospective study was undertaken using iodine-123 metaiodobenzylguanidine (MIBG) single-photon emission tomography (SPET). The study groups consisted of ten diabetic patients with cardiac autonomic neuropathy (group I) and six without autonomic neuropathy (group II). Autonomic nervous function tests, thallium scan, radionuclide ventriculographic data including ejection fraction and wall motion study, and 24-h urine catecholamine levels were evaluated. 123I-MIBG SPET was performed at 30 min and 4h following injection of 3 mCi of 123I-MIBG in groups I and II and in normal subjects (n=4). On planar images, the heart to mediastinum (H/M) ratio was measured. Defect pattern and severity of MIBG uptake were qualitatively analysed on SPET. Compared with control subjects, diabetic patients had a reduced H/M ratio regardless of the presence of clinical autonomic neuropathy. There was no difference in H/M ratio between groups I and II. On SPET images, focal or diffuse defects were demonstrated in all patients in group I, and in five of the six patients in group II. The extent of defects tended to be more pronounced in group I than in group II. In conclusion, 123I-MIBG scan was found to be a more sensitive method than clinical autonomic nervous function tests for the detection of autonomic neuropathy in diabetes.

3-Iodobenzylguanidine↗

Coculture of human spermatozoa with reproductive tract cell monolayers can enhance sperm functions better than coculture with Vero cell monolayers.

PURPOSE: In order to develop a better system for support of human sperm function in vitro, we conducted studies to evaluate whether reproductive tract cells are better than non-reproductive tract cells as an adjunt in that regard. METHODS: Human spermatozoa were cocultured with Vero cells, with human oviduct cells and endometrial cells, and without cells (control) for either 1, 4, or 24 hr. Sperm motility was then analyzed with a computer-aided sperm analyzer (CASA-Hamiliton Thron, HTM IVOS Motility Analyzer). Aliquots of spermatozoa incubated for 24 hr were also stained with Hoechst 33258 and FITC-PNA to evaluate the status of acrosome in live cells. RESULTS: Significant differences (P < 0.05) between the oviduct cell and the control groups after 24 hr were evident in the curvilinear velocity (VCL) (81.4 +/- 13.4 vs 60.0 +/- 14.1 microns/sec) and amplitude of lateral head displacement (ALH) (5.2 +/- 0.6 vs 4.1 +/- 0.5 microns). The incidence of acrosome reaction of live sperm was significantly higher in the endometrial cell group than in the controls (25.4 +/- 9.9 vs 6.6 +/- 2.4%; P < 0.001). CONCLUSIONS: Coculture with human reproductive tract cells seems to improve some functional parameters of human spermatozoa. Coincubation with such cell lines, especially oviduct cells, might be a feasible approach to optimization of human spermatozoa for assisted fertilization using subfertile or frozen-thawed samples. We think coincubating human spermatozoa with a human reproductive tract cell line, especially oviduct cells, might be a feasible approach in preparing human spermatozoa for assisted fertilizatioin in subfertile and frozen-thawed semen samples.

Acrosome↗

Cardiac energy metabolism at several stages of adriamycin-induced heart failure in rats.

To evaluate the changes in myocardial energy metabolism in the progressively failing myocardium, we measured myocardial level of adenosine triphosphate (ATP) using high-performance liquid chromatography (HPLC), and levels of lactate, alanine and free carnitine using 1H-nuclear magnetic resonance (NMR) spectroscopy in rats injected with adriamycin. The drug was injected intraperitoneally 2.5 mg/kg 6 times over a period of 2 weeks. Measurements were obtained 1 day (1 d), 3 weeks (3 w) and 6 weeks (6 w) after the last injection. No deaths were observed until the end of the 3rd week. The cumulative mortality rate 6 weeks after the last injection was 48%. ATP and free carnitine levels were not significantly changed at 1 d, while myocardial lactate was increased by 33% from the control values (P < 0.05). Lactate levels were reduced significantly, but not progressively, at 3 w (31% of control values) and at 6 w (69% of control values). Similar changes were observed in alanine levels. Free carnitine levels were progressively decreased at 3 w (74% of control values) and at 6 w (57% of control values). Changes in ATP levels paralleled those of free carnitine. Data suggest that a decrease in the myocardial level of free carnitine may be involved in progression of the heart failure induced by adriamycin in rats.

Adenosine Triphosphate↗

Uptake of human immunodeficiency virus envelope protein gp120 by human trophoblast in culture.

OBJECTIVE: Our purpose was to determine whether human trophoblast has a cell surface CD4 antigen that will bind to gp120, the envelope protein of human immunodeficiency virus. STUDY DESIGN: Uptake of iodine 125-labeled gp120 by trophoblast in culture was measured. Particular attention was paid to technical details that may have caused the contradictory results reported by previous investigators: the source of the recombinant gp120, the method of radioiodination, and the isolation procedure of trophoblast to ensure elimination of contaminating cells, particularly macrophages. RESULTS: Uptake of transferrin-free iodine 125-labeled gp120 to trophoblast was unaffected by adding a 200 molar excess of gp120, by preincubating gp120 with soluble CD4 to block the CD4 binding sites on gp120 and by preincubation of trophoblast with a blocking antibody to CD4 (OKT4a). In contrast, uptake of gp120 by CD4-positive H9 human lymphocytes was reduced 79% by a 200 molar excess of gp120 and > 50% by a CD4-blocking antibody. CONCLUSIONS: Uptake of gp120 to trophoblast is by a high capacity, CD4-independent mechanism that is probably nonspecific and may be related to the mechanism for binding other circulating glycoproteins in maternal blood.

Animals↗