Greatly accelerated lymphadenopathy and autoimmune disease in lpr mice lacking tumor necrosis factor receptor I

Fas and TNF receptor I (TNF-RI) share homology at their cytoplasmic death domain and belong to the same gene family, but utilize different pathways to signal activation-induced cell death. To determine the combined effects of defective TNF-RI and Fas signaling on lymphadenopathy and autoimmune disease, we backcrossed TNF-RI knockout mice (Tnfr1(0/0)) with Fas-deficient C57BL/6-lpr/lpr mice. Tnfr1(0/0)lpr/lpr mice developed greatly accelerated lymphadenopathy and autoantibody production compared with C57BL/6-lpr/ lpr mice. Tnfr1(0/0)-lpr/lpr mice also exhibited high mortality and early onset autoimmune disease characterized by massive mononuclear cell infiltration in liver, kidney, lung, and knee joints. These results indicate that the Fas-mediated apoptosis defect in lpr mice is accelerated in the absence of TNF-RI and that normal expression of TNF-RI might partially compensate for the Fas-mediated apoptosis defect of mononuclear cells in lpr mice.

Inhibition of Nur77/Nurr1 leads to inefficient clonal deletion of self-reactive T cells

The Nur77/Nurr1 family of DNA binding proteins has been reported to be required for the signal transduction of CD3/T cell receptor (TCR)-mediated apoptosis in T cell hybridomas. To determine the role of this family of DNA-binding proteins in thymic clonal deletion, transgenic (Tg) mice bearing a dominant negative mutation were produced. The transgene consisted of a truncated Nur77 (deltaNur77) gene encoding the DNA-binding domain of Nur77 ligated to a TCR-beta enhancer resulting in early expression in thymocytes. Apoptosis of CD4+CD8+ thymocytes mediated by CD3/TCR signaling was greatly inhibited in the deltaNur77 Tg mice, compared with non-Tg littermates, after treatment with anti-CD3 or anti-TCR antibody in vivo and in vitro. Clonal deletion of self-reactive T cells was investigated in deltaNur77-Db/HY TCR-alpha/beta double Tg mice. There was a five-fold increase in the total number of thymocytes expressing self-reactive Db/HY TCR-alpha/beta in the deltaNur77-TCR-alpha/beta double Tg male mice. Deficient clonal deletion of self-reactive thymocytes was demonstrated by a 10-fold increase in the CD4+CD8+ thymocytes that expressed Tg TCR-alpha/beta. There was an eightfold increase in the CD8+, Db/HY TCR-alpha/beta T cells in the lymph nodes (LN) of delta Nur77-Db/HY TCR-alpha/beta double Tg compared with Db/HY TCR-alpha/beta Tg male mice. In spite of defective clonal deletion, the T cells expressing the Tg TCR were functionally anergic. In vivo analysis revealed increased activation and apoptosis of T cells associated with increased expression of Fas and Fas ligand in LN of deltaNur77-Db/HY TCR-alpha/beta double male mice. These results indicate that inhibition of Nur77/Nurr1 DNA binding in T cells leads to inefficient thymic clonal deletion, but T cell tolerance is maintained by Fas-dependent clonal deletion in LN and spleen.

A novel histone H4 mutant defective in nuclear division and mitotic chromosome transmission

The histone proteins are essential for the assembly and function of th e eukaryotic chromosome. Here we report the first isolation of a temperature-sensitive lethal histone H4 mutant defective in mitotic chromosome transmission Saccharomyces cerevisiae. The mutant requires two amino acid substitutions in histone H4: a lethal Thr-to-Ile change at position 82, which lies within one of the DNA-binding surfaces of the protein, and a substitution of Ala to Val at position 89 that is an intragenic suppressor. Genetic and biochemical evidence shows that the mutant histone H4 is temperature sensitive for function but not for synthesis, deposition, or stability. The chromatin structure of 2 micrometer circle minichromosomes is temperature sensitive in vivo, consistent with a defect in H4-DNA interactions. The mutant also has defects in transcription, displaying weak Spt- phenotypes. At the restrictive temperature, mutant cells arrest in the cell cycle at nuclear division, with a large bud, a single nucleus with 2C DNA content, and a short bipolar spindle. At semipermissive temperatures, the frequency of chromosome loss is elevated 60-fold in the mutant while DNA recombination frequencies are unaffected. High-copy CSE4, encoding an H3 variant related to the mammalian CENP-A kinetochore antigen, was found to suppress the temperature sensitivity of the mutant without suppressing the Spt- transcription defect. These genetic, biochemical, and phenotypic results indicate that this novel histone H4 mutant defines one or more chromatin-dependent steps in chromosome segregation.

Immunohistochemical studies of macrophages and MHC class II-positive cells in the iris and ciliary body of Lewis rats

PURPOSE

To investigate the density, distribution and morphology of macrophages and MHC class II-positive dendritic cells in the iris and ciliary body of lewis rats.

METHODS

Immunohistochemistry was performed using monoclonal antibodies specific to monocytes and macrophages (ED1, ED2) and MHC class II-positive cells (OX6) on wholemounts of the iris-ciliary body complex isolated form normal lewis rats.

RESULTS

A well developed network of macrophages was present in the iris and ciliary body of normal lewis rats. These cells, morphologically displaying dendritiform or pleiomorphic appearance, were more densely arranged in mid-iris (950 +/- 189 cells/mm2) than in iris base (482 +/- 78 cells/mm2) and pupil margin (595 +/- 92 cells/mm2). A similar network of MHC class II-positive cells with a cell density 452 +/- 78 cells/mm2 was almost uniformly distributed in the iris of normal lewis rats.

CONCLUSIONS

A network of macrophages and MHC class II-positive cells was established in the iris and ciliary body of normal lewis rats. These cells may be involved biologically in the generation of anterior chamber associated immune deviation-inducing signal within the anterior chamber and the transferring of this signal from the eye to the spleen, and pathophysiologically in the pathogenesis of uveoretinitis.

C-Ha-ras oncogene in oral leukoplakia tissues

The amplification and the G-T mutation at codon 12 of the C-Ha-ras oncogene in oral leukoplakia tissues were analyzed by using polymerase chain reaction (PCR) and molecular biologic technique. The results showed that these tissues had no amplification of Ha-ras oncogene. Only one case harbored G-T mutation in 11 oral leukoplakias, but this mutation was absent in 10 normal oral mucosal tissues. The possible role and significance of C-Ha-ras oncogene in oral precancerous lesions were also discussed.

Molecular cloning and characterization of the CER2 gene of Arabidopsis thaliana

Plants with defects in the synthesis of their epicuticular wax layer, eceriferum mutants (cer), are readily detected by the naked eye as bright green glossy plants when compared with the more glaucous normal plants. In a previous report, evidence was presented for the isolation of three lines from the Arabidopsis thaliana transformant collection (BRL5, BRL7 and BRL9) which failed to complement the cer2 mutant isolated previously. The analysis of the chemical composition of the epicuticular wax of these mutants suggests that the cer2 mutant of Arabidopsis is defective in very long chain fatty acid elongation. This paper reports the molecular cloning of the CER2 gene of Arabidopsis through the isolation of plant DNA flanking the site of T-DNA insertion as well as the characterization of the two independent T-DNA insertion mutant alleles, BRL5 and BRL9, of this gene. In the mutant line BRL5, T-DNA was found to be inserted in the second exon of the CER2 gene whereas in BRL9, T-DNA is inserted in the only intron of this gene. Nucleotide sequence analysis suggests that the ORF encodes a 47.3 kDa polypeptide. High levels of CER2 transcripts were detected in stems and flowers. The predicted amino acid sequence of the CER2 gene product reveals little homology with known protein sequences. In accordance with structural characterization of the T-DNA insertion mutants, no evidence of transcripts derived from the CER2 gene was found in either BRL5 or BRL9.

Analysis of the growth and transformation suppressor domains of promyelocytic leukemia gene, PML

The promyelocytic leukemia gene (PML) involved in the t(15;17) (q22;q12) translocation in acute promyelocytic leukemia is a growth suppressor. To elucidate the functional domains of PML, several mutants lacking the nuclear localization signal (PMLnls-), the dimerization domain (PMLdim-), the proline-rich domain at the N-terminal (PMLpro-), the proline-rich RING finger motif (PMLpr-), the proline-rich RING finger B-box-1 (PML-prb-), the serine-proline-rich domain at the C-terminal (PMLsp-), and the double mutant (PMLprb-nls-) have been constructed. Immunofluorescence staining of transiently transfected NIH3T3 cells demonstrated that the RING finger motif, dimerization domain, and nuclear localization signal are all required for the formation of PML oncogenic domains (PODs). Immunofluorescence staining of transiently transfected GM637D human fibroblasts indicated that expression of PMLprb-, PM-Lnls-, and PMLprb-nls- led to a significant reduction or, in some cases, complete elimination of PODs. PMLdim-, PMLnls-, PMLpr-, PMLprb-, and PMLprb-nls- mutants were found to lose their ability to suppress transformation of NIH3T3 cells by activated neu, while PMLpro- and PMLsp- mutants did not. These results suggest that the ability of PML to form a POD is essential for suppression of growth and transformation. Furthermore, since PMLprb-, PMLnls-, and PMLprb-nls- mutants could block the suppression effect of wild-type PML on transformation of NIH3T3 cells by the neu oncogene, these PML mutants are potential dominant negative inhibitors of PML. Our study also suggests that the RING finger motif may interact with other nuclear proteins.

[Eyebrow reconstruction by a scalp island flap based on the frontal branch of the superficial temporal artery]

The author studied the course and measured the length of the frontal branch of the superficial temporal artery in 30 normal subjects. 19 eyebrows were reconstructed in 11 burned patients using the scalp island flap based on the frontal branch of the superficial temporal artery. The results were satisfactory. The reconstructed eyebrows looked natural with wooly hair of the frontal hairline. This method can be used not only in male patients but also in female or pediatric patients.

Macrophages in the retina of normal Lewis rats and their dynamics after injection of lipopolysaccharide

PURPOSE

To investigate the density, distribution, and morphology of macrophages (bone marrow-derived microglia) and major histocompatibility complex (MHC) class II-positive cells in the retina of Lewis rats and the dynamics of these cells after systemic lipopolysaccharide (LPS) injection.

METHODS

Immunohistochemistry was carried out using monoclonal antibodies specific to monocytes and macrophages (ED1, ED2) and MHC class II-positive cells (OX-6) on whole-mounts of the retina obtained from Lewis rats before and at different time points after footpad injection of 200 micrograms of LPS.

RESULTS

The inner layers of the normal retina contained a network of macrophages, whereby ED1 and ED2 staining revealed similar results. Macrophages were either dendritiform or pleiomorphic in morphology, with the former predominant. The density of positive cells was higher at the peripheral part and the periequatorial part (271 +/- 10 cells/mm2 and 267 +/- 9 cells/mm2, respectively) than at the posterior part (196 +/- 11 cells/mm2; P < 0.0001 in both cases). Lipopolysaccharide injection induced an early adherence of monocytes to retinal blood vessels, followed by a massive influx of the macrophages into the retina. The ED1-ED2 positive cells showed a variety of morphologic appearances: large round cells, pleiomorphic cells, and dendritiform cells. Pleiomorphic cells were striking at 48 hours, whereas dendritiform cells were predominant in the whole retina at 72 hours and thereafter. On day 14, the dendritiform cell numbers returned to approximately preinjection levels. Major histocompatibility class II-positive cells could not be found in the normal retina, nor after LPS injection.

CONCLUSIONS

The network of MHC class II-negative microglia in the retina were studied. These cells may play an important role in immunoregulation and stability of the immunologic microenvironment within the retina. Systemic LPS injection was followed by a massive influx of macrophages into the retina. The absence of MHC class II-positive cells in the retina after LPS challenge may be an important protective mechanism against possible autoimmune damage.

Arterial oxygen saturation in Tibetan and Han infants born in Lhasa, Tibet

BACKGROUND

Reduced oxygen availability at high altitude is associated with increased neonatal and infant mortality. We hypothesized that native Tibetan infants, whose ancestors have inhabited the Himalayan Plateau for approximately 25,000 years, are better able to maintain adequate oxygenation at high altitude than Han infants, whose ancestors moved to Tibet from lowland areas of China after the Chinese military entered Tibet in 1951.

METHODS

We compared arterial oxygen saturation, signs of hypoxemia, and other indexes of neonatal wellbeing at birth and during the first four months of life in 15 Tibetan infants and 15 Han infants at 3658 m above sea level in Lhasa, Tibet. The Han mothers had migrated from lowland China about two years previously. A pulse oximeter was placed on each infant's foot to provide measurements of arterial oxygen saturation distal to the ductus arteriosus.

RESULTS

The two groups had similar gestational ages (about 38.9 weeks) and Apgar scores. The Han infants had lower birth weights (2773 +/- 92 g) than the Tibetan infants (3067 +/- 107 g), higher concentrations of cord-blood hemoglobin (18.6 +/- 0.8 g per deciliter, vs. 16.7 +/- 0.4 in the Tibetans), and higher hematocrit values (58.5 +/- 2.4 percent, vs. 51.4 +/- 1.2 percent in the Tibetans). In both groups, arterial oxygen saturation was highest in the first two days after birth and was lower when the infants were asleep than when they were awake. Oxygen saturation values were lower in the Han than in the Tibetan infants at all times and under all conditions during all activities. The values declined in the Han infants from 92 +/- 3 percent while they were awake and 90 +/- 5 percent during quiet sleep at birth to 85 +/- 4 percent while awake and 76 +/- 5 percent during quiet sleep at four months of age. In the Tibetan infants, oxygen saturation values averaged 94 +/- 2 percent while they were awake and 94 +/- 3 percent during quiet sleep at birth and 88 +/- 2 percent while awake and 86 +/- 5 percent during quiet sleep at four months. Han infants had clinical signs of hypoxemia--such as cyanosis during sleep and while feeding--more frequently than Tibetans.

CONCLUSIONS

In Lhasa, Tibet, we found that Tibetan newborns had higher arterial oxygen saturation at birth and during the first four months of life than Han newborns. Genetic adaptations may permit adequate oxygenation and confer resistance to the syndrome of pulmonary hypertension and right-heart failure (subacute infantile mountain sickness).

Activation of mitogen-activated protein kinase cascades by p21-activated protein kinases in cell-free extracts of Xenopus oocytes

In the evolutionarily distant yeasts Saccharomyces cerevisiae and Schizosaccharomyces pombe, genetic evidence suggests that activation of pheromone-induced mitogen-activated protein kinase (MAPK) cascades involves the function of the p21cdc42/racl-activated protein kinases (PAKs) Ste20 and Shk1, respectively. In this report, we show that purified Ste20 and Shk1 were each capable of inducing p42MAPK activation in cell-free extracts of Xenopus laevis oocytes, while a mammalian Ste20/Shk1-related protein kinase, p65pak (Pak1), did not induce activation of p42MAPK. In contrast to p42MAPK, activation of JNK/SAPK in Xenopus oocyte extracts was induced by both the yeast Ste20 and Shk1 kinases, as well as by mammalian Pak1. Our results demonstrate that MAPK cascades that are responsive to PAKs are conserved in higher eukaryotes and suggest that distinct PAKs may regulate distinct MAPK modules.

Pulmonary blastoma: an ultrastructural and immunohistochemical study with special reference to nuclear filament aggregation

A case is presented of pulmonary blastoma occurring in the right upper lobe of a 25-year-old man without distinct clinical features and laboratory abnormality. Light microscopic analysis revealed that the tumor was composed of branching glands and morulae embedded in a primitive but bland mesenchyme. Immunohistochemically the epithelial cells were immunoreactive for cytokeratins, S-100 protein, protein gene product 9.5, chromogranin A, calcitonin, and Ki-67 (MIB-1); the mesenchymal cells were immunoreactive for vimentin, actin, cytokeratins, and Ki-67; and all the tumor cells were negative for p53, estrogen receptor protein, and human chorionic gonadotropin beta. Characteristically, many epithelial cells contained optically clear nuclei which were immunoreactive for biotin (M743). Electron microscopic analysis revealed that the optically clearing change was due to replacement of the central area of the nuclei by a mass of parallel-arranged 7- to 10-nm filaments, and biotin-immunoreactive products were mainly localized in the nuclear matrix. Additionally, spherical bodies were identified in the cytoplasm of the nuclear filament-aggregated cells, suggestive of an intimate pathogenetic association of the two morphological abnormalities. The similarity of the aggregated nuclear filaments to those observed in gestational endometrium and ovarian endometrioid carcinoma implies that a similar mechanism plays a role in the pathogenesis of these abnormalities.

Synthesis, characterization and antibacterial activity of novel Fe(III), Co(II), and Zn(II) complexes with norfloxacin

Three novel complexes of norfloxacin (abbreviated as NFL), [M(NFL)2(H2O)2]Cl3.6H2O, (M = Fe, Co), and [Zn(NFL)2]Cl2.7H2O, have been prepared. The compounds were characterized by IR, UV-Vis, NMR spectra, molar conductivity, and elemental analyses. In all of the complexes, the ligand NFL was coordinated through two carboxyl oxygen atoms. Octahedral and tetrahegon geometries have been proposed for Fe(III)-, Co(II)-complexes and Zn(II)-complex, respectively. In vitro test of susceptibility of Fe(III)- and Zn(II)-complexes showed stronger activity than that of norfloxacin against G(-) E.Coli and Bacillus dysenteriae bacteria.

[Chemical constituents of Hemsleya pengxianensis W.J. Chang]

Six compounds were isolated from the tubers of Hemsleya pengxianensis and identified as chikuset-susaponin IV a, hemslosides Ma1, G1, H1, dihydrocucurbitacin F-25-O-acetate and dihydrocucurbitacin F on the basis of chemical and physical properties and spectral data. They were all isolated from this plant for the first time.

Prognostic implication of the p53 protein and Ki-67 antigen immunohistochemistry in malignant fibrous histiocytoma

BACKGROUND

Mounting evidence indicates that p53 regulates cell growth and abnormal p53 immunophenotypic expression is associated with an unfavorable prognosis for patients with some types of carcinoma. The prognostic significance of p53 overexpression in malignant fibrous histiocytomas (MFHs) of soft tissue has not yet been elucidated.

METHODS

Expressions of p53 protein and Ki-67 antigen in 54 primary MFHs of soft tissue were investigated immunohistochemically and indexed quantitatively by counting the number of immunoreactive nuclei versus the total neoplastic nuclei in the representative fields of each tumor to evaluate their prognostic implications and interrelations with other clinicopathologic parameters.

RESULTS

The percentages (labeling indices [LIs]) of p53 and Ki-67-immunoreactive nuclei versus the total neoplastic nuclei were 0.1-93.2% (mean +/- standard deviation [SD], 40.6% +/- 21.8%) and 5.3-90.8% (mean +/- SD, 42.7% +/- 29.4%), respectively. The Ki-67 LI correlated with histologic grade (P = 0.01498), primary tumor size (P = 0.04985), disease free interval (reverse correlation, P = 0.00776), and recurrence and metastasis (P = 0.00360). The p53 LI correlated with primary tumor size (P = 0.00431) but did not show any significant correlation with histologic grade, Ki-67 LI, primary tumor size, disease free interval, or recurrence and metastasis. Other significant correlations included histologic grade and disease free interval (P = 0.00010), primary tumor size and disease free interval (reverse correlation, P = 0.00869), histologic grade and recurrence (P = 0.02714), and primary tumor size and primary tumor location (P = 0.00028). In the grouped survival analysis, patients with recurrence or metastasis or with tumors of larger size (> or = 7 cm), high histologic grade, or higher Ki-67 LI (> or = 25%) had a significantly reduced survival (P < 0.05). The different p53 immunohistochemical expression and the different histologic types did not reflect different cumulative survival (P > 0.05). Regression analysis revealed that the primary tumor size and histologic grade, but not Ki-67 or p53 LIs, were independent statistical variables for prognostication.

CONCLUSIONS

These results indicate that (1) primary tumor size and histologic grade are two important prognostic factors, (2) Ki-67 LI should be used in adjunct with other main prognostic factors for patients with MFHs, and (3) nuclear p53 overexpression in MFHs of soft tissue is a comparatively common event that has no prognostic implication.

Differentiation and proliferative activity in benign and malignant cartilage tumors of bone

To assess the histological grade in benign and malignant cartilage tumors of bone by more objective methods, we examined the differentiation and proliferative activity of tumor cells in six enchondromas, five chondroblastomas, and 13 chondrosarcomas immunohistochemically. A variable number of cells in all tumors showed S-100 protein and vimentin immunoreactivity. In fully differentiated cartilage of enchondromas and low grade chondrosarcomas, tenascin, which is an extracellular matrix glycoprotein, was present in small amounts or absent but was increased at the periphery of tumor lobules and even in the matrix throughout the high grade chondrosarcomas. Higher rate and intensity of proliferating cell nuclear antigen (PCNA) reactivity were found in chondrosarcomas, especially in spindle-shaped cells of high grade tumors, than in enchondromas. The distribution of PCNA-positive cells almost corresponded to the regions with tenascin reactivity. One tumor of high grade chondrosarcoma showed p53 protein immunoreactivity. Aberrant expression of cytokeratin was observed in four chondroblastomas. The expression of desmin was identified in relatively large proportions of enchondromas and chondrosarcomas, regardless of their benign or malignant nature and histological grade. Smooth muscle or muscle-specific actins also were present in a smaller number of tumors. Based on these findings, it is concluded that unusual staining characteristics were present, in addition to those of a chondroblastic nature, in the cartilage tumors of bone. Tenascin and PCNA positivity of various degrees in all chondroblastomas may suggest that they are chondrogenic tumors having a relatively high proliferative activity, albeit their benign clinical course. Proliferative activity of tumor cells in enchondromas and chondrosarcomas correlated well with their histological grade. Tenascin may play a role in promoting tumor cell proliferation of cartilagenous neoplasms and, on the other hand, the alterations of extracellular matrix involving tenascin synthesis seem to be a result of tumor development.

[Anaesthesia for esophageal reconstruction with abdominal viscera in non-thoracotomy]

Radical resection of carcinoma of the hyopharynx and cervical esophagus usually involves pharyngolaryngo-esophagectomy and esophaged reconstruction with stomach or colonic replacement. From 1983 to 1994, 139 patients underwent the operations in our hospital. Although no thoracotomy, the extensive involvement of the neck, thorax and abdomen in the operation made the anesthesia difficult. There were 66 patients whose blood pressure dropped more than 3 kPa in the course of trans-mediastinum extraction of esophagus and gastric pull-up. There were injury of posterior wall of trachea in 2 patients and spleen rupture in 3. However, no anesthetic complications occurred during the operation.

P-ANCA in monozygotic twins with inflammatory bowel disease

Perinuclear antineutrophil cytoplasmic antibodies (P-ANCA) have been demonstrated in patients with ulcerative colitis and in a higher frequency than expected in their first degree relatives. A hypothesis was proposed that P-ANCA is genetically determined and may represent a subclinical marker of genetic susceptibility to ulcerative colitis. This study analysed P-ANCA in monozygotic twins with inflammatory bowel disease to evaluate this hypothesis further. P-ANCA was analysed with indirect immunofluorescence technique in 12 monozygotic twin pairs with ulcerative colitis and 14 twin pairs with Crohn's disease. Furthermore, the study included 21 non-twin patients with ulcerative colitis, 18 non-twin patients with Crohn's disease, and 52 healthy controls matched for sex and age. In ulcerative colitis P-ANCA occurred in nine of 14 (64.3%) monozygotic twins and in 13 of 21 (61.9%) non-twin cases, which was significantly different compared with healthy controls who were positive in three of 52 (5.8%) cases (p < 0.0001). P-ANCA was found in two of 10 (20%) healthy twin siblings to twins with ulcerative colitis, which was not significantly different from healthy controls (p = 0.18). The results in Crohn's disease did not differ from healthy controls. Previous findings of P-ANCA occurring in ulcerative colitis but not in Crohn's disease are supported. This study does not support the hypothesis that P-ANCA is a subclinical marker of genetic susceptibility to ulcerative colitis.

Retroflexion of the sigmoidoscope for the detection of rectal cancer

Flexible sigmoidoscopy is a procedure that is commonly used by primary care physicians for the evaluation of rectal disorders and for colorectal screening. Retroflexion of the endoscope improves views of the anorectum and rectal vault, which increases the diagnostic yield of sigmoidoscopy. We report three cases of rectal lesions that were not detected when flexible sigmoidoscopy was performed without retroflexion. The lesions were all malignant or premalignant. The illustrative cases demonstrate the value of retroflexion in flexible sigmoidoscopy for the detection of rectal lesions.

[Dynamic obstruction of the left ventricular outflow tract by prosthesis dysfunction]

We report on a case of dynamic left ventricular (LV) outflow tract obstruction combined with a prosthetic valve dysfunction 13 years following mitral valve replacement with a Hancock bioprosthesis in a 46-year-old patient. Previously, repeated echocardiographic controls had been performed at regular intervals and the prosthesis had been found to be oversized and seated in abnormal position, with projection of the struts into the LV outflow tract. Moreover, a mild chronic LV outflow tract obstruction had been diagnosed upon intermittent findings of relatively high velocity in the outflow tract. Clinically, however, the patient had been stable and the function of the prosthesis had been good. With the onset of the mitral regurgitation due to prosthesis failure, a dynamic obstruction to LV outflow occurred, with severe narrowing of the LV outflow tract by a strut of the bioprosthesis during systole. Subsequently, a low cardiac output syndrome developed. The patient was referred for a mitral valve reoperation. The valve was replaced with a Sorin Bileaflet Carbon prosthesis. On the setting of a mild chronic LV outflow obstruction due to the oversized prosthesis and its abnormal position, hypercontractile cardiac function as a result of mitral regurgitation may have caused the dynamic and symptomatic LV outflow tract obstruction.

Aneurysmal fibrous histiocytoma of the skin. A histological, immunohistochemical, and ultrastructural study

We present two cases of aneurysmal fibrous histiocytoma of the skin on the lower extremities of a 41-year-old man and a 23-year-old woman. Both the tumors appeared clinically as cutaneous nodules with a recent history of rapid growth and showed microscopically a unique formation of blood-filled tissue spaces and a storiform proliferation of histiocyte-like and fibroblast-like cells in a capillary-rich stroma. Such clinical and histologic features fit the original description of this entity. Immunohistochemically the tumor cells of both cases were immunoreactive for factor XIIIa, Mac 387, and vimentin and gave negative results for factor VIII-related antigen, desmin, actin, and S-100 protein. Ultrastructurally the tumors were composed mainly of siderosome-containing histiocyte-like cells, fibroblast-like cells, and intermediate cells and lacked prominent proliferation of endothelial cells. Thus, the ultrastructural findings agreed with the immunophenotypes expressed by the tumor cells, supporting the fibrohistiocytic origin of this lesion. In view of the recent rapid growth, the presence of hemorrhagic pseudocysts, the extravasation of erythrocytes, and the high vascularity of the present tumors, we emphasize the importance of distinguishing this lesion from angiomatoid fibrous histiocytoma and cutaneous malignancies of mesenchymal origin.

Structural and functional characterization of two wheat histone H2B promoters

Two wheat histone H2B genes (TH123 and TH153) were isolated. Nucleotide sequence analysis revealed that some characteristic sequence motifs were conserved in both the 5'- and 3'-flanking regions. A canonical TATA box and several CCAAT sequences were present in the presumed promoter regions. Motifs similar or identical to the hexamer (ACGTCA) and octamer (CGCGGATC) motifs that are positive cis-acting elements of the wheat H3 (TH012) promoter were also observed in both the H2B promoters. A gel mobility shift assay indicated that the hexamer and hexamer-like motifs bound the wheat bZIP proteins HBP-1a and/or HBP-1b in vitro. A novel sequence motif, (A/T)(G/A)AAAT(A/G), was found downstream of a translational stop codon as observed in several plant histone H2B cDNAs. Promoter activity was analyzed with H2B promoter-GUS fusion genes in the transient system using tobacco protoplasts. Studies of the promoter function in transgenic tobacco plants showed that the H2B promoters were preferentially active in meristematic tissues. Taken together, our data indicate that the H2B genes are regulated, in part, by the same mechanism as found in H3 and H4 gene transcription.

Defective expression of hematopoietic cell protein tyrosine phosphatase (HCP) in lymphoid cells blocks Fas-mediated apoptosis

Protein tyrosine dephosphorylation after Fas cross-linking occurred in Fas apoptosis-sensitive CEM-6 cells but not in Fas apoptosis-resistant MOLT-4 cells, and apoptosis in the CEM-6 cells could be inhibited by the protein tyrosine phosphatase inhibitor, pervanadate. The time course and level of dephosphorylation were correlated with increased hematopoietic cell protein tyrosine phosphatase (HCP) activity, but not with the activity of two other tyrosine phosphatases. The level of expression of HCP was correlated with Fas apoptosis function in eleven human and murine Fas-positive lymphoid cell lines. Expression of recombinant HCP in the MOLT-4 cell line converted this Fas apoptosis-resistant cell line to Fas apoptosis sensitive. HCP-mutant mev/mev mice exhibited increased expression of Fas but decreased Fas-mediated apoptosis function in lymphoid organs after anti-mouse Fas antibody treatment in vivo. Thus, HCP-mediated protein dephosphorylation is involved in the delivery of the Fas apoptosis signal in lymphoid cells.

[Immunocomplexes in tuberculous lesions]

The immunohistochemical staining was used to detect the BCG antigen, IgG, IgM, IgA and the complement C3 in the tuberculous lesions. The results showed that the III type of allergic reaction induced by immunocomplexes (IC) was one of the pathogenesis of tuberculosis. Detection of specific IC in tuberculous lesions was helpful for pathologic diagnosis of tuberculoions.

[Reduction mammaplasty using glandular pedicle]

A new technique for reduction mammaplasty with a glandular pedicle was designed based on the anatomical study of the vascular supply to the breast. The features of the procedure include using a pyramidal glandular pedicle that is reliably vascularized and definitely placed, maintaining a thin layer of parenchyme attached to the flap and the modified invert "T" closure. Clinical applications provided aesthetic and safe results of reliable nipple-areola survival, simplicity in breast mound creature and preservation of nipple sensitivity and the possibility of nursing function as well as less complications.

Association of childhood rhabdomyosarcoma with neurofibromatosis type I and birth defects

Rhabdomyosarcoma (RMS) is an uncommon malignant soft tissue sarcoma whose cause is largely unknown. Reported risk factors include genetic alterations (e.g., p53 mutations, a defective gene at 11p15.5, or specific chromosomal translocation of t(2:13)), and parents' use of drugs around the time of conception. We present results from a national, case-control study of 249 RMS cases (170 males and 79 females) and 302 controls (196 males and 106 females). The cases, aged 0-20 years at diagnosis, were identified via the Intergroup RMS Study-III during 1982-1988. Controls were selected by random digit telephone dialing. As a supplement to the original study, information on genetic diseases and birth defects (BD) was collected from the subjects' parents by telephone interview. Fifty-six (22.5%) cases and 55 (18.2%) controls were reported to have genetic diseases or BD (odds ratio [OR] = 1.30,95% confidence interval [CI] = 0.85-2.02, P = .21). The case group had a significantly higher frequency of neurofibromatosis type I (NF1) than did the control group, i.e., five cases (2.0%) had NF1 vs. zero controls (P = .02). The case group also had a higher frequency of major BDs than did the control group (6.0% vs. 2.6%, OR = 2.36, 95% CI = 0.92-6.52, P = .05). However, this excess was only observed in males (7.6% vs. 2.6%, OR = 3.16, 95% CI = 1.02-10.41, P = .02). Among the 15 cases having both RMS and major BDs, six (40.0%) had both conditions in the same regional anatomic site: Two (13.3%) had both in the extremities, two (13.3%) in the genitourinary system, and two in the head and neck. These findings suggest that common genetic mechanisms or in utero exposures may be involved in the development of many childhood tumors and congenital abnormalities.

Physical and social impact of alpha 1-antitrypsin deficiency: results of a survey

BACKGROUND

Emphysema associated with alpha 1-antitrypsin deficiency can impose serious impairment.

OBJECTIVE

To gather information about the impact of severe alpha 1-antitrypsin deficiency.

METHODS

Mail survey, descriptive statistics.

RESULTS

We sent a survey to 1730 subscribers to a national newsletter, 850 of whom had previously stated they had alpha 1-antitrypsin deficiency. A total of 414 questionnaires were returned; 398 respondents said they had alpha 1-antitrypsin deficiency, and 300 said they had the PiZZ phenotype. Sixty-six respondents who said they had the disease did not know their phenotype. Among the 304 respondents with severe deficiency, the mean age at the time symptoms first appeared was 35.0 years, but the mean age when the disease was diagnosed was 41.3 years. Overall, 75.3% of respondents with severe deficiency reported at least one adverse effect: 44.4% retired early, and 19.1% changed to a physically easier job. The duration of diagnostic delay correlated with the degree of adverse psychosocial effects.

CONCLUSIONS

Alpha 1-antitrypsin deficiency frequently escapes diagnosis despite many medical encounters. Affected individuals are often unaware of basic details of their disease. Many patients report adverse psychosocial effects. Delay in diagnosing this disease is associated with adverse psychosocial effects.

An inductively coupled plasma-time-of-flight mass spectrometer for elemental analysis. Part I: Optimization and characteristics

An inductively coupled plasma-time-of-flight mass spectrometer (ICP-TOFMS) has been constructed and evaluated for elemental analysis. The instrument produces analog spectra similar to those from quadrupole inductively coupled plasma mass spectrometers. The large abundance of Ar ions is deflected away from the microchannel plate detector to reduce detector dead time and space-charge complications. The ICP-TOFMS, operated in a linear (nonreflecting) mode, currently has a resolving power of 500 (full width at half maximum). Present ion optics employed in the instrument require a trade-off between signal-to-noise ratio and resolving power. In addition, mass-dependent kinetic energies in the supersonic beam created in the ICP mass spectrometer interface cause a mass bias in the right-angle TOFMS because the ions must be steered to the detector to compensate for their velocity in the supersonic beam direction. In the current design the sampling duty cycle is only approximately 3%, thereby limiting sensitivity. However, positive potentials applied to the right-angle extraction region can increase sensitivity by a factor of 2-4 by slowing down the ions that enter the extraction zone. The transmission efficiency of the TOFMS is approximately 20% and is limited by divergence of the ion packet in the drift tube.

Role of charge and hydration in effects of polysialic acid on molecular interactions on and between cell membranes

Previous studies have shown that the polysialic acid (PSA) moiety associated with the neural cell adhesion molecule (NCAM) has strong antiadhesive properties that can influence a variety of cell-cell interactions. Based on the size and structure of this long linear homopolymer, we have proposed that the activity of PSA results from its physical properties. In the present study, the premise that the charge and hydration properties of PSA underlie its effects on membrane vesicle aggregation is investigated through the manipulation of ionic strength. The results establish that the antiadhesive properties of PSA are accentuated at low ionic strength, where charge and hydration cause expansion of the polymer size, and are absent at high ionic strengths, where the polymer size collapses. These large effects of PSA on aggregation were shown not to result from changes in the osmolarity of the solvent or from the relatively small effect of ionic strength on the intrinsic functional properties of the adhesion receptors. In addition to this influence on overall membrane-membrane interaction, PSA was found to have a highly localized and ionic strength-sensitive effect on the binding of monoclonal antibodies to NCAM. Together these results suggest that the charge and hydration properties of PSA can impede both molecular interactions between apposing membranes and more direct contact of NCAM with other proteins at the cell surface.

Higher exercise performance and lower VO2max in Tibetan than Han residents at 4,700 m altitude

To examine the hypothesis that the pathway of adaptation to high altitude in natives differs considerably from that in newcomers, we measured maximal O2 uptake (VO2max), minute ventilation, anaerobic threshold (AT), blood lactate, and blood gases during maximal exercise in 17 lifelong Tibetan residents and 14 acclimatized Han Chinese newcomers living at the altitude of 4,700 m. The two groups were similar in age, height, and weight, and the subjects were nonathletes. Although VO2max was significantly lower in the Tibetans than in the Hans (30.4 +/- 1.5 vs. 36.0 +/- 1.9 ml.min-1.kg-1 STPD; P < 0.05), at maximal exercise effort the exercise workload was greater (167.7 +/- 4.2 vs. 150.0 +/- 5.9 W; P < 0.05). The mean AT values (in % VO2max) in the Tibetan and Han subjects were 84.1 and 61.6%, respectively (P < 0.01). Minute ventilation at maximal exercise was significantly lower in the Tibetans than in the Hans (68.4 +/- 3.4 vs. 79.7 +/- 4.1 l/min BTPS; P < 0.05), whereas heart rate at maximal effort was equivalent in the two groups. The Tibetans showed lower blood lactate value than did the Hans both before and at the end of exercise. We conclude that the Tibetan natives have higher exercise performance and AT but lower VO2max and blood lactate concentration than do acclimatized Han newcomers. These results may reflect the effects of genetic or peripheral adaptation factors in the Tibetan natives.

[Sequence of light chain variable region gene of a monoclonal antibody to human hepatocarcinoma]

The isolation of the rearranged immunoglobulin genes from a hybridoma cell line, which is a prerequisite for the construction of a recombinant antibody, can easily be achieved by PCR. We have determined the nucleotide sequence of the variable region of L chain of a high affinity monoclonal antibody HAb27 directed to human hepatocarcinoma. Analysis of the nucleotide sequence of the light chain V region of HAb27 revealed that the V kappa sequence was 85% identical to germline V kappa Ox1 sequence.

Regulation of the expression of annexin VIII in acute promyelocytic leukemia

Annexin VIII is a calcium-dependent phospholipid-binding protein previously identified as a blood anticoagulant based on in vitro studies. However, the physiologic function of annexin VIII remains unknown. In acute promyelocytic leukemia (APL) the annexin VIII gene is highly expressed, but its expression is undetectable in the blasts of other acute leukemias. In the present investigation, we showed using the APL-derived NB4 cell line that expression of the annexin VIII gene is regulated at the transcription level during induced differentiation by all-trans retinoic acid (ATRA). The half-life of the annexin VIII mRNA is about 5 to 6 hours, as determined by using actinomycin D as a transcription inhibitor. Analysis of the expression of annexin VIII protein in NB4 cells and in APL samples showed a consistent expression of a predominant 36-kD protein and a weak 72-kD protein. After ATRA-induced differentiation of NB4 cells, the annexin VIII protein level reduced gradually, but a detectable level persisted even after 4 days of induction. Because annexin VIII mRNA becomes undetectable after 48 hours of ATRA induction, this result indicates that annexin VIII is a relatively stable protein. A multiple tissue Northern blot analysis was performed, and we found that annexin VIII is normally expressed in the placenta and the lung. Cellular localization of the annexin VIII protein was determined by immunofluorescence staining and subcellular fractionation. These results indicated that annexin VIII is predominantly localized to the plasma membrane. The annexin VIII is neither an extracellular protein nor associated with the cell surface suggesting that it does not play a role in blood coagulation in vivo. The plasma membrane localization and its property as a phospholipase inhibitor suggests that annexin VIII may have a role in the signal transduction pathway in the APL cells.

Ossifying fibromyxoid tumor of soft parts: a morphological and immunohistochemical study

A case is presented of ossifying fibromyxoid tumor of soft parts (OFMTSP) which occurred in the left cheek of a 59 year old Chinese woman. Histologically, the tumor was located in the subcutis with a fibrous pseudocapsule that contained discontinuous rims of mature trabecular bone. The tumor cells were small, round to ovoid with a uniform, round nucleus and a pale or slightly eosinophilic cytoplasm. Most of the cells were arranged in a random manner, some in a vague lace-like pattern. Mitotic figures were extremely rare. The stroma appeared fibromyxoid with scattered foci of mucinous lakes. Immunohistochemically, most of the neoplastic cells displayed immunoreactivities for S-100 protein, S-100 protein alpha, vimentin and alpha-smooth muscle actin; many tumor cells were positive for desmin. The tumor also showed stromal immunoreactivity for type IV collagen and was negative for cytokeratins, epithelial membrane antigen, glial fibrillary acidic protein, neurofilaments, muscle-specific actin, Leu-7, myelin-basic protein, osteocalcin and melanoma-specific antigen. The immunophenotypes expressed by the present OFMTSP seem to reflect two lineages of neoplastic cell differentiation, that is of nerve sheath and of smooth muscle; at the present stage, it is premature to diagnose this lesion as either nerve sheath or smooth muscle tumor.

Detection of AML1/ETO fusion transcript as a tool for diagnosing t(8;21) positive acute myelogenous leukemia

The nonrandom chromosomal translocation t(8;21)(q22;q22) can be found frequently in acute myelogenous leukemia with maturation (AML-M2). The breakpoint of this translocation has been cloned and characterized, and fusion transcript AML1/ETO has been identified. Reverse transcription polymerase chain reaction (RT-PCR) can be used to amplify the breakpoint site of AML1/ETO in t(8;21)-positive AML-M2 patients. The chimeric transcript can be detected in all 16 (100%) t(8;21)-positive AML-M2 patients. In all samples, the size of the amplified DNA fragments and pattern of restriction digest were identical, indicating that the t(8;21) translocation breakpoint occurs within a single intron of the AML1 and ETO genes. Interestingly, this fusion transcript was also detected in one of 13 AML-M2 patients without the t(8;21) translocation, indicating that a masked translocation involving chromosomes 8 and 21, exists in AML. Minimal residual disease was detected by semi-nested RT-PCR in all four patients tested, who had been in complete remission for 12, 15, 34, and 52 months, respectively. These results indicate that RT-PCR amplification of the AML1/ETO fusion transcript is a powerful tool for diagnosing and monitoring minimal residual disease in AML-M2 patients.

Mechanism of pain and cytoskeletal properties in angioleiomyomas: an immunohistochemical study

Angioleiomyoma is a solitary subcutaneous tumor characterized by pain in about half of patients with this tumor, and the pathogenesis of this pain has been a cause of much debate. To clarify the mechanism of pain and cytoskeletal property of tumor cells, 50 angioleiomyomas were studied clinicopathologically and immunohistochemically. The tumors occurred preferentially on the extremities, particularly the lower leg (46%), and the female to male ratio was 1.9:1. They were classified into three histological subtypes: (i) solid (30 cases); (ii) venous (15 cases); and (iii) cavernous (five cases). The pain and/or tenderness were present in 26 out of 49 patients (52%), in which small nerve fibers immunoreactive for S-100 protein and PGP9.5 were identified within the capsule of 20 tumors (77%) and the tumor stroma of 18 (69%), irrespective of the histological subtypes. In 24 patients where the pain was absent or unknown, nerves were observed within the capsule of 19 tumors (79%) and tumor parenchyma of 10 (42%). Many cells in all 50 tumors were positive for alpha-smooth muscle actin, and a relatively large number of cells in many tumors were positive for vimentin, desmin and collagen type IV. Also, cytokeratin (CAM5.2) reactivity was scattered in a few cells of four tumors. From these findings, the peculiar pain of angioleiomyomas could be mediated by the nerve fibers especially located within the tumor parenchyma. Although the expression of intermediate filaments in angioleiomyomas was heterogeneous, the overall cytoskeletal features were of smooth muscle cell differentiation.

Comparative epidemiology of selected midline congenital abnormalities

We present comparative epidemiologic characteristics of five congenital abnormalities that have been suggested to result from midline abnormal developmental disturbances: esophageal atresia with or without tracheoesophageal fistula (EA/TEF), imperforate anus with or without fistula (IA/F), omphalocele (OM), bladder exstrophy (BE), and diaphragmatic hernia (DH). The purpose was to assess the extent of epidemiologic similarities among these five defects. Data were collected as part of a population-based case-control study of infants with these defects born to mothers residing in Maryland, Washington, D.C., or Northern Virginia from 1980 through 1987. The estimated annual birth prevalences (per 10,000 live births) and 95% confidence intervals (CI) of these five defects were 0.40 (0.26-0.61) for BE, 1.34 (1.08-1.67) for OM, 1.59 (1.29-1.95) for DH, 2.11 (1.76-2.53) for EA/TEF, and 2.97 (2.55-3.46) for IA/F. The birth prevalence of IA/F and DH increased between 1980 and 1987. In contrast to the other four defects, DH showed a significant male preponderance (rate ratio 1.57, 95% CI 1.03-2.47), a significant white excess (rate ratio white:other, 1.56, 95% CI 1.00-2.48), and a lower proportion of multiple associated defects (30% vs. 46-61%). We concluded from this study that the descriptive epidemiology of diaphragmatic hernia is different from that of the other four defects. This finding may imply differences in etiologic and pathogenetic mechanisms underlying DH.

[Amino acid analysis of retinal S-antigen and interphotoreceptor retinoid-binding protein]

Retinal S-antigen and interphotoreceptor retinoid-binding protein (IRBP) were purified by DEAE-Sephacel ionexchange chromatography and Con A Sepharose affinity chromatography. Amino acid analysis of the S-antigen and IRBP was carried out and compared with that presented by others. The possible reason for difference with regard to some amino acids and related problems were analyzed and discussed.

The innervation of intradermal nevi. On the nevus-axon relations

In the study of the histogenesis of intradermal nevi, the nevus cell-Schwann cell relationship has been a matter of long debate. We have demonstrated a dense axonal supply in the intradermal nevi by protein gene product 9.5 (PGP 9.5) immunohistochemistry. There were small nerve bundles between nevus cell nests and numerous individual axons in the nests of all the intradermal nevi studied. The distribution of these axons was more dense in the deeper and middle portions than in the superficial portion of the nevi. The significance and morphogenesis of this rich axonal supply in the intradermal nevi remain obscure, but this nevic neurotropism suggests an intimate mutual interaction between nevus cells and axons: possibly, some activities of nevus cells stimulating axonal proliferation, or nevus cell migration into the preexisting nerves. The presence of the proliferated axons may have some influences upon Schwannian transformation of the nevus cells. The mode of contact between nevus cell and axon, the presence of true Schwann cells surrounding the proliferated axons and the demonstration of myelin structure should be investigated by further electron microscopic study.

Coordinate gene expression of five subclass histones and the putative transcription factors, HBP-1a and HBP-1b, of histone genes in wheat

The expression of genes encoding five histones (H1, H2A, H2B, H3 and H4) and the putative transcription factors HBP-1a (17) and HBP-1b (c38) was examined during early germination and in various tissues of young wheat seedlings. The steady-state levels of core histone (H2A, H2B, H3 and H4) mRNAs were coordinately cell cycle-dependent and paralleled the rate of DNA synthesis during early germination, whereas the expression pattern of the linker histone (H1) genes differed. The five subclass histone genes were actively expressed in the meristematic tissues of young seedlings. Moreover, H1 genes were expressed in leaves that consist mostly of non-proliferating cells, in which core histone genes showed little expression. Quantitative alterations to the mRNAs of the putative transcription factors HBP-1a (17) and HBP-1b (c38) of wheat histone genes were similar to those of the core histone mRNAs, suggesting that both factors function in the cell cycle-dependent expression of wheat core histone genes.

Detection of the AML1/ETO fusion transcript in the t(8;21) masked translocation in acute myelogenous leukemia

The fusion transcript AML1/ETO was detected in the bone marrow of two t(8;21)-negative acute myelogenous leukemia (AML) patients by means of reverse transcription-polymerase chain reaction. This fusion transcript is identical to the one transcribed from the t(8;21) translocation base, as deduced from (a) the size and restriction pattern of the amplified DNA fragment and (b) the DNA sequence analysis of the fusion junction. We also showed that the ETO gene is highly expressed in these patients, much as it is in the t(8;21)-positive AML. Southern blot analysis showed rearrangement of the AML1 gene in one of the patients. Together, our results demonstrate that there is a masked t(8;21) translocation in AML that is not detectable by cytogenetic analysis but is able to transcribe an AML1/ETO fusion transcript similar to that transcribed in t(8;21)-positive AML-M2 patients.

[Dig-DNA probe for etiologic diagnosis in tuberculosis patients]

We have detected the sputa DNA with nonradioactive probe which is labelled to the specific sequence DNA, 31bp-188bp, by dig-11-dUTP. It showed that both the Sensitivity and specificity are satisfactory. The positive rate of the 80 specimens are 56.25%, and the 30 positive specimens of sputum culture are all positive when detected by the Dig-DNA probe.

Diagnosis of Helicobacter pylori infection by means of a polymerase chain reaction assay for gastric juice aspirates

A polymerase chain reaction (PCR) assay for Helicobacter pylori was developed with use of primer sequences from the ureA structural gene coding for the small subunit of urease. The PCR amplification was 100% specific for H. pylori in tests with 40 stock isolates of this species and with 30 control organisms, including two species of urease-producing Helicobacter. Thirty-four dyspeptic patients were evaluated by culture and histologic assessment of antral biopsy samples as well as by PCR of gastric juice aspirates. In 26 of the 34 patients, infection with H. pylori was diagnosed by culture and histology. PCR correctly identified 25 of these 26 patients. All eight patients with negative cultures and histologic findings also had negative PCR results. In this group of patients, therefore, PCR had a sensitivity of 96% and a specificity of 100%. Thus PCR of gastric juice aspirates can be used to diagnose H. pylori infection. This information is important since gastric juice can be aspirated through a nasogastric tube without gastroduodenoscopy. In addition, since clinical samples can be collected at one institution and mailed to a laboratory at another without compromising the outcome of the test, diagnostic PCR is accessible even to those clinicians at whose institutions the technology required for the procedure is not available.