Binding of the human cytomegalovirus 80-kDa immediate-early protein (IE2) to minor groove A/T-rich sequences bounded by CG dinucleotides is regulated by protein oligomerization and phosphorylation

The 80-kDa immediate-early regulatory protein IE2 of human cytomegalovirus (HCMV) functions as an essential positive transactivator of downstream viral promoters, but it also specifically down-regulates transcription from the major immediate-early promoter through a 14-bp DNA target motif known as the cis-repression signal (CRS) located at the transcription start site. The IE2 protein purified from bacteria as a fusion product of either staphylococcal Protein A/IE2(290-579) or glutathione-S-transferase (GST)/IE2(346-579) bound specifically to a [32P]-labeled CRS oligonucleotide probe in an in vitro electrophoretic mobility shift assay (EMSA). In contrast, no direct interaction with the CRS probes could be detected with IE2 wild-type protein in extracts from infected or transfected mammalian cells or when synthesized by in vitro translation. However, in vitro phosphorylation of GST/IE2(346-579) by incubation with either the catalytic subunit of protein kinase A (PKA) or a HeLa cell nuclear extract strongly inhibited its DNA-binding activity. This process required ATP hydrolysis and could be reversed by subsequent incubation with bacterial alkaline phosphatase. Importantly, dephosphorylation of the constitutively expressed native IE2 protein present in a nuclear extract from the U373(A45) cell line unmasked a specific CRS DNA-binding activity that could be supershifted with anti-IE2 monoclonal antibody (mAb). A series of high-molecular-weight hetero-oligomeric DNA-bound structures of intermediate mobility were formed in EMSA assays when a mixture of staphylococcal Protein A/IE2 and GST/IE2 was coincubated with the CRS probe. Coincubation with a DNA-binding negative but dimerization-competent GST/IE2 deletion mutant competitively inhibited DNA-binding by staphylococcal Protein A/IE2, whereas coincubation with a GST/IE2 deletion mutant that lacked the ability to both dimerize and bind to DNA failed to influence the mobility of the DNA-bound staphylococcal Protein A/IE2 protein. Therefore, IE2 appears to bind to DNA as a higher-order oligomer in which the presence of subunits with mutant DNA-binding domains interferes with the overall DNA-binding function. A series of point mutations introduced into each of nine conserved motifs throughout the DNA-binding and dimerization domain, all of which abolish the ability of the transfected intact IE2 protein to autoregulate the MIE promoter, also all lacked the ability to bind to CRS sequences as GST/IE2(346-379) fusion proteins. Detailed analysis of point mutations in the 14-bp CRS target DNA binding motif revealed that IE2 binds in a relatively sequence-independent manner to 10-bp-long A/T-rich DNA elements bounded on each side by CG dinucleotides. Moreover, the A/T-rich minor groove binding agent distamycin, but not the G/C-rich minor groove binding agent chromomycin-A3, actively competed with IE2 for binding to the CRS motif in a dose-dependent fashion. In conclusion, IE2 binds preferentially as multimerized dimers to A/T-rich sequences in the minor groove that are flanked on both sides by appropriately spaced CG dinucleotides, and inhibition of the DNA-binding or oligomerization activity by PKA phosphorylation probably accounts for the inactivity of the mammalian and in vitro translated forms of the protein.

Regulation of cyclic peptide biosynthesis and pathogenicity in Cochliobolus carbonum by TOXEp, a novel protein with a bZIP basic DNA-binding motif and four ankyrin repeats

HC-toxin is an epoxide-containing cyclic tetrapeptide that is a critical virulence determinant in the pathogenic interaction between the filamentous fungus Cochliobolus carbonum and maize. HC-toxin exerts a potent cytostatic effect on plant and animal cells by inhibiting histone deacetylase. The biosynthesis of HC-toxin by C. carbonum is controlled by a complex genetic locus, TOX2, that contains multiple, duplicated copies of genes encoding export and biosynthetic enzymes. A new gene in the TOX2 complex, TOXE, has now been isolated. Mutation of TOXE by targeted gene disruption has no effect on growth and sporulation but abolishes HC-toxin production and pathogenicity. TOXE is required for the expression of three genes with a known or putative role in HC-toxin production, but is not required for expression of HTS1, which encodes the large, multifunctional peptide synthetase that is the central enzyme in HC-toxin biosynthesis. At its N-terminus, TOXEp has a bZIP basic DNA binding domain, but it does not contain any discernible leucine zipper or helix-loop-helix. At its carboxy terminus, TOXEp contains four ankyrin repeats. In having these two common regulatory motifs in a single polypeptide, TOXEp appears to represent a novel class of regulatory protein. TOXE is present only in HC-toxin-producing (Tox2+) isolates of C. carbonum. Most Tox2+ isolates have two copies: in strain SB111, one copy of TOXE is on the same 3.5-Mb chromosome that contains all of the other genes known to be involved in HC-toxin biosynthesis, and the second copy of TOXE is on a 0.7-Mb chromosome.

EXG1p, a novel exo-beta1,3-glucanase from the fungus Cochliobolus carbonum, contains a repeated motif present in other proteins that interact with polysaccharides

Genomic and cDNA copies of EXG1, a gene encoding an exo-beta1, 3-glucanase from the plant pathogenic fungus Cochliobolus carbonum, were isolated. The gene contains two introns of 50 and 53 bp, and the mRNA has a 5'-untranslated region of 90 nt and a 3'-untranslated region of 159 nt. The deduced protein product, EXG1p, has a predicted signal peptide of 17 amino acids, but based on the known N-terminus of the mature protein is further processed to remove an additional 25 amino acids. The sequence of EXG1p is not closely related to any other known protein, but has a low similarity (29% overall amino acid identity) to BGN13.1, an endo-beta1,3-glucanase from the mycoparasitic fungus Trichoderma harzianum. EXG1p contains two imperfect copies of a 23-amino acid motif that is found in several other proteins that interact with polysaccharides, including plant and bacterial polygalacturonases, phage neck appendage protein, phage endoneuramidase, and bacterial mannuronan epimerase.

Estimation of the extent of osteonecrosis of the femoral head using MRI

The extent of necrosis is the main determining factor in the outcome of osteonecrosis of the femoral head and is best measured by MRI. Using statistical analyses, we have evaluated the accuracy and repeatability of seven different methods of measuring the extent of necrosis, of which three demonstrate good or acceptable accuracy. For the general observer their repeatability is poor; only for experienced observers were they reasonable. We conclude that within an institution or for personal use, the accuracy of some methods is acceptable, and repeatability reasonable. None is appropriate for international use.

Routine biliary sphincterotomy may not be indispensable for endoscopic pancreatic sphincterotomy

BACKGROUND AND STUDY AIMS

It is generally accepted that biliary sphincterotomy is mandatory to avoid possible cholestasis and infection due to edema after pancreatic sphincterotomy. However, biliary sphincterotomy is an invasive procedure and the above claim on dual sphincterotomy has not been proven by a prospective randomized study. The aim of our study was to determine whether cholangitis develops more frequently when the patients have not undergone concomitant biliary sphincterotomy during the endoscopic pancreatic sphincterotomy.

PATIENTS AND METHODS

From January 1990 to November 1997, 60 patients (38 men, 22 women, age range 19-45 years) with non-alcoholic chronic calcifying pancreatitis were prospectively enrolled. The patients with jaundice (bilirubin > or = 3 mg/dl), cholangitis, or parenchymal liver disease were excluded. The patients were randomly subjected either to dual sphincterotomy (group I, n = 30) or to pancreatic sphincterotomy alone (group II, n = 30). Groups I and II were further classified as IA (or IIA) and IB (or IIB), according to the level of serum alkaline phosphatase (sALP) and the diameter of the common bile duct (CBD). Group IA (or IIA) was defined when abnormal in both sALP (> or = 2 times the upper limit of normal) and CBD diameter (> or = 12 mm), whereas group IB (or IIB) was defined when normal, or solely abnormal in sALP or CBD diameter.

RESULTS

As a complication after sphincterotomy, pancreatitis developed in one of eight patients (12.5%) in group IA, whereas cholangitis occurred in one of 22 (4.5%) and hemorrhage in one of 22 (4.5%) cases in group IB. By contrast, in group IIA, the cholangitis developed in 56% (five of nine patients), which was significantly more frequent than in any other groups (P < 0.05). Hemorrhage (one of 21, 4.8%) and pancreatitis (one of 21, 4.8%) occurred in group IIB.

CONCLUSIONS

Our results suggest that dual sphincterotomy may be indicated only in patients who have both dilated choledochus and elevated alkaline phosphatase in chronic pancreatitis. Routine biliary sphincterotomy may not be indispensable for pancreatic sphincterotomy.

Severe aplastic anemia induced by ticlopidine: report of two cases

Aplastic anemia is a rare side-effect associated with ticlopidine therapy. We report two cases of severe aplastic anemia developed after the use of ticlopidine. A 51-year-old woman took ticlopidine at 500 mg/day for 49 days to prevent a secondary stroke. She developed fever and dizziness within 49 days of initiating ticlopidine therapy. A 70-year-old woman was started on ticlopidine after coronary stent insertion. Fifty days after starting ticlopidine, she developed fever and dizziness. Both patients showed pancytopenia and were diagnosed as aplastic anemia which were confirmed by bone marrow examination. Both patients were hospitalized and received antibiotics, blood products and hematopoietic growth factors. Four and seven weeks after the withdrawal of ticlopidine, the hematologic parameters of each patient improved. A complete blood count should be monitored during ticlopidine therapy to check for cytopenia.

Plagiorchis muris: recovery, growth and development in albino rats

Metacercariae of Plagiorchis muris, obtained from naturally infected dragonflies, Sympetrum eroticum, successfully established in 4-week-old albino rats up to 14 days post-infection (p.i.) but by day 28 p.i. the recovery rate had significantly decreased. The genital primordia in excysted metacercariae were differentiated into those of metraterm, Mehlis' gland, ovary and cirrus pouch, with the primordial testes appearing on day 1 p.i. The vitellaria and eggs in the uterus were present in flukes on days 2 and 4 p.i., respectively. Mature flukes were established in the lower part of the small intestine on day 5 p.i., with the peak of egg production occurring on day 14 p.i. Growth of the flukes continued up to day 28 p.i.

ATM binds to beta-adaptin in cytoplasmic vesicles

Inherited mutations in the ATM gene lead to a complex clinical phenotype characterized by neuronal degeneration, oculocutaneous telangiectasias, immune dysfunction, and cancer predisposition. Using the yeast two-hybrid system, we demonstrate that ataxia telangiectasia mutated (ATM) binds to beta-adaptin, one of the components of the AP-2 adaptor complex, which is involved in clathrin-mediated endocytosis of receptors. The interaction between ATM and beta-adaptin was confirmed in vitro, and coimmunoprecipitation and colocalization studies show that the proteins also associate in vivo. ATM also interacts in vitro with beta-NAP, a neuronal-specific beta-adaptin homolog that was identified as an autoantigen in a patient with cerebellar degeneration. Our data describing the association of ATM with beta-adaptin in vesicles indicate that ATM may play a role in intracellular vesicle and/or protein transport mechanisms.

Disruption of PML subnuclear domains by the acidic IE1 protein of human cytomegalovirus is mediated through interaction with PML and may modulate a RING finger-dependent cryptic transactivator function of PML

Both of the major immediate-early (IE) proteins IE1 and IE2 of human cytomegalovirus (HCMV) as well as input viral DNA and sites of viral IE transcription colocalize with or adjacent to punctate PML domains (PML oncogenic domains [PODs] or nuclear domain 10) in the nucleus within the first few hours after infection of permissive human fibroblasts. However, colocalization of IE1 and PML in PODs is only transient, with both proteins subsequently redistributing into a nuclear diffuse form. These processes are believed to promote efficient viral IE transcription and initiation of DNA synthesis especially at low multiplicities of infection. To examine the mechanism of PML displacement by IE1, we carried out indirect immunofluorescence assay experiments with plasmids expressing intact or deleted forms of PML and IE1 in DNA-transfected cells. The results demonstrated that deletion of the C-terminal acidic region of IE1 uncouples the requirements for displacement of both endogenous and coexpressed PML from those needed to target to the PODs. Mutant PML proteins containing either a Cys point mutation within the N-terminal RING finger domain or a small deletion (of positions 281 to 304) within the coiled-coil region did not localize to the PODs but instead gave a nuclear diffuse distribution, similar to that produced by intact PML in the presence of IE1. Endogenous PML also colocalized with IE1 in metaphase chromosomes in HCMV or recombinant adenovirus type 5-IE1-infected HF cells undergoing mitosis, implying that there may be a direct physical interaction between IE1 and PML. Indeed, a specific interaction between IE1 and PML was observed in a yeast two-hybrid assay, and the strength of this interaction was comparable to that of IE2 with the retinoblastoma protein. The RING finger mutant form of PML showed a threefold-lower interaction with IE1 in the yeast system, and deletion of the N-terminal RING finger domain of PML abolished the interaction. Consistent with the IFA results, a mutant IE1 protein that lacks the C-terminal acidic region was sufficient for interaction with PML in the yeast system. The two-hybrid interaction assay also showed that both the N-terminal RING finger domain and the intact coiled-coil region of PML are required cooperatively for efficient self-interactions involving dimerization or oligomerization. Furthermore, truncated or deleted GAL4/PML fusion proteins that retained the RING finger domain but lacked the intact coiled-coil region displayed an unmasked cryptic transactivator function in both yeast and mammalian cells, and the RING finger mutation abolished this transactivation property of PML. Therefore, we suggest that a direct interaction between IE1 and the N-terminal RING finger domain of PML may inhibit oligomerization and protein-protein complex formation by PML, leading to displacement of PML and IE1 from the PODs, and that this interaction may also modulate a putative conditional transactivator function of PML.

c-Fes tyrosine kinase binds to and activates STAT3 after granulocyte-macrophage colony-stimulating factor stimulation

Granulocyte-macrophage colony stimulating factor (GM-CSF) induces proliferation and maturation of myeloid progenitor cells and also activates neutrophils. In order to investigate the pleiotropic effects of GM-CSF stimulation, we examined the signaling pathways of protein tyrosine kinases (PTKs) and signal transducers and activators of transcription (STATs) in GM-CSF-dependent proliferation of leukemia cells. Using TF-1, a GM-CSF-dependent human erythroleukemia cell line, we found that GM-CSF enhanced DNA-binding and tyrosine phosphorylation of STAT3. GM-CSF receptor (GM-CSFR) and c-Fes tyrosine kinase were also activated upon GM-CSF stimulation. Furthermore, c-Fes formed a complex with STAT3. Experiments using a c-Fes mutant that lacked tyrosine kinase activity revealed that the activation of STAT3 is kinase-dependent, but that the c-Fes-STAT3 interaction is not affected by c-Fes tyrosine kinase activity. The results suggest that STAT3 is activated by c-Fes tyrosine kinase through direct interaction during hematopoietic cell proliferation induced by GM-CSF.

Evaluation and mapping of the DNA binding and oligomerization domains of the IE2 regulatory protein of human cytomegalovirus using yeast one and two hybrid interaction assays

The 86-kDa IE2 nuclear phosphoprotein encoded by the human cytomegalovirus (HCMV) major immediate-early (MIE) gene behaves as both a non-specific transactivator of viral and cellular gene expression and as a specific DNA-binding protein targeted to the cis-repression sequence (CRS) at the cap site of its own promoter/enhancer region. Although the IE2 protein produced in bacteria has been shown to bind to the 14-bp palindromic CRS motif and IE2 synthesized in vitro forms stable dimers in solution through the conserved C-terminus of the protein, there is no direct evidence as yet that the intracellular mammalian forms of IE2 do so. Here, we show that the intact HCMV IE2 protein both binds to CRS DNA and dimerizes in yeast cells. In a one-hybrid assay system, a GAL4/IE2 fusion protein expressed in yeast cells activated target HIS3 expression only when CRS sites were located upstream of the GAL1 minimal promoter, but failed to do so on mutant CRS sites, demonstrating a requirement for sequence-specific DNA-binding by IE2. Examination of a series of deletion and triple amino acid point mutations in the C-terminal half of IE2 mapped the domains required for DNA-binding in yeast to the entire region between codons 313 and 579, whereas in the previous in-vitro study with truncated bacterial GST fusion proteins, it was mapped to between codons 346 and 579. Transient co-transfection assays with deleted IE2 effector genes in Vero cells showed that the extra segment of IE2 between codons 313 and 346 is also required for both autoregulation and transactivation activity in mammalian cells. In a two-hybrid assay to study IE2 self-interations, we generated both GAL4 DNA-binding (DB) and activation domain (A)/IE2 fusion proteins and showed that IE2 could also dimerize or oligomerize through the C-terminus of the protein in yeast cells. Domains required for this interaction were all mapped to within the region between codons 388 and 542, which is coincident with the domain mapped previously for dimerization by co-translation and immunoprecipitation in vitro. Comparison of the domains of the IE2 protein required for CRS binding and dimerization in yeast suggests that these activities correlate precisely with requirements for the negative autoregulation function of the IE2 protein in mammalian cells.

Workup and management of traumatic hematuria

Hematuria is an important indicator of genitourinary tract injury after trauma. Correct initial evaluation of hematuria will affect diagnosis, management, and outcome of resultant injuries. This article presents recommendations for further evaluation when hematuria is found, depending on the mechanism of injury and clinical status of the patient. Once injuries have been adequately diagnosed and staged, appropriate management decisions can be made with urologic consultation.

Role of mononuclear cells of IgA nephropathy on ICAM-1 expression in mesangial cells

OBJECTIVES

To investigate the possible role of mononuclear cells and their products in the pathogenesis of IgA nephropathy, in vitro expression of ICAM-1 on cultured mouse mesangial cell (MC) was examined after stimulation with mononuclear cell culture supernatant from patients with IgA nephropathy.

METHODS

Peripheral blood mononuclear cells (PBMC) were isolated and cultured from 18 patients with primary IgA nephropathy, 8 normal controls and 5 patients with non-IgA nephropathy (FSGS 1, MGN 3, MPGN 1). ICAM-1 expression on cultured mouse MC by TNF-alpha, IL-1 beta and culture supernants of PBMC were analyzed using a cell ELISA method. The concentration of IL-1 beta and TNF-alpha in culture supernatants was measured by using a commercially available radioimmunoassay kit.

RESULTS

Addition of human recombinant TNF-alpha induced an increased ICAM-1 expression in a dose-dependent manner. The expression of ICAM-1 was further increased after co-stimulation with TNF-alpha and IL-1 beta. Addition of PBMC culture supernatants into mouse MC induced significantly higher expression of ICAM-1 by supernatants from the patients with IgA nephropathy compared with that from normal controls. The concentration of TNF-alpha and IL-1 beta in supernatants from the patients with IgA nephropathy was significantly higher than that from those with non-IgA nephropathy.

CONCLUSION

TNF-alpha and IL-1 released from mononuclear cells induced the up-regulation of ICAM-1 expression and this may be related to the immune pathogenesis of IgA nephropathy.

Tetraparesis following dental extraction: case report and discussion of preventive measures for cervical spinal hyperextension injury

This concerns a patient with compression myelopathy following passive hyperextension of the cervical spine during a dental procedure. Although he had been asymptomatic prior to the procedure, subsequent cervical spinal imaging revealed advanced spondylosis and spinal stenosis. Spinal stenosis is often asymptomatic for a long time. However, when radiculomyelopathy occurs after minor trauma to the head or neck, the patient is often found to have spinal stenosis. Specifically, hyperextension of a cervical spine with spondylotic changes can lead to compression myelopathy. Acquired spinal stenosis correlates positively with aging. As the size of the elderly population continues to increase the prevalence of cervical spondylotic radiculo-myelopathy will likely increase as well. Since appropriate precautions against potential neurologic damage can be undertaken, we suggest radiographic screening for pre-existing spinal stenosis prior to a procedure requiring hyperextension of the neck. Preventive measures for individuals with asymptomatic spondylotic changes and education of all health-care professionals to avoid abrupt or prolonged hyperextension of the cervical spine is emphasized.

The major immediate-early proteins IE1 and IE2 of human cytomegalovirus colocalize with and disrupt PML-associated nuclear bodies at very early times in infected permissive cells

The major immediate-early (MIE) gene products of human cytomegalovirus (HCMV) are nuclear phosphoproteins that are thought to play key roles in initiating lytic cycle gene regulation pathways. We have examined the intranuclear localization pattern of both the IE1 and IE2 proteins in virus-infected and DNA-transfected cells. When HCMV-infected human diploid fibroblast (HF) cells were stained with specific monoclonal antibodies, IE1 localized as a mixture of nuclear diffuse and punctate patterns at very early times (2 h) but changed to an exclusively nuclear diffuse pattern at later times. In contrast, IE2 was distributed predominantly in nuclear punctate structures continuously from 2 to at least 12 h after infection. These punctate structures resembled the preexisting PML-associated nuclear bodies (ND10 or PML oncogenic domains [PODs]) that are disrupted and dispersed by the IE110 protein as a very early event in herpes simplex virus (HSV) infection. However, HCMV differed from HSV by leading instead to a change in both the PML and SP100 protein distribution from punctate bodies to uniform diffuse patterns, a process that was complete in 50% of the cells at 2 h and in 90% of the cells by 4 h after infection. Confocal double-label indirect immunofluorescence assay analysis confirmed that both IE1 and IE2 colocalized transiently with PML in punctate bodies at very early times after infection. In transient expression assays, introduction of IE1-encoding plasmid DNA alone into Vero or HF cells produced the typical total redistribution of PML into a uniform nuclear diffuse pattern together with the IE1 protein, whereas introduction of IE2-encoding plasmid DNA alone resulted in stable colocalization of the IE2 protein with PML in the PODs. A truncated mutant form of IE1 gave large nuclear aggregates and failed to redistribute PML, and similarly a deleted mutant form of IE2 failed to colocalize with the punctate PML bodies, confirming the specificity of these effects. Furthermore, both Vero and U373 cell lines constitutively expressing IE1 also showed total PML relocalization together with the IE1 protein into a nuclear diffuse pattern, although a very small percentage of the cells which failed to express IE1 reverted to a punctate PML pattern. Finally, the PML redistribution activity of IE1 and the direct association of IE2 with PML punctate bodies were both confirmed by infection with E1A-negative recombinant adenovirus vectors expressing either IE1 or IE2 alone. These results confirm that transient colocalization with and disruption of PML-associated nuclear bodies by IE1 and continuous targeting to PML-associated nuclear bodies by IE2 are intrinsic properties of these two MIE regulatory proteins, which we suggest may represent critical initial events for efficient lytic cycle infection by HCMV.

Investigation of refolding condition for Pseudomonas fluorescens lipase by response surface methodology

Response Surface Methodology (RSM) was used to investigate optimal refolding conditions of Pseudomonas fluorescens lipase which was expressed as inclusion body in E. coli. Three interacting factors, protein concentration, pH and guanidine hydrochloride (GdnHCl) concentration were selected as the variables of RSM. The protein concentration did not affect the refolding yield within the selected range (50-340 micrograms ml-1) at low temperatures of 4 and -15 degrees C, but it was a critical factor at 25 degrees C and refolding yield significantly decreased with increasing protein concentration. The pH and GdnHCl were significant factors in all experimental conditions. But there was no trends of optimal pH depending on temperature and additives, just showing the optimum at neutral pH. Glycerol shifted optimal GdnHCl concentration to higher side, while arginine to lower side. Therefore, it was concluded that glycerol and arginine deprives and supplements GdnHCl, respectively. In this study, RSM made it possible to investigate successfully the optimal conditions of in vitro refolding and to elucidate interactions between refolding factors with a minimum number of experiments. Under the optimal condition determined by RSM, approximately 90% refolding yield was obtained and it was a 30% increase over the conventional method.

Deciding eligibility for transplantation when a donor kidney becomes available

The expectation of transplant success for some patient/donor-kidney matches can be so low that transplantation is not considered an option. The issue may be framed as deciding the minimum expectation of transplant success that would justify a patient's eligibility for transplantation with an available donor kidney. If the minimum is set too high, the patient will be eligible for very few donor kidneys and will wait excessively for transplantation. If the minimum is set too low, the patient has a greater risk of graft failure once transplantation has been done. A decision model calculates the minimum predicted one-year graft survival rate that would determine eligibility for an available donor kidney, with the goal of maximizing quality-adjusted life expectancy. The minimum predicted one-year graft survival rate depends on the patient's health and demographic characteristics and attitudes about quality of life with kidney-replacement therapies. Graft survival rates and quality-adjusted life expectancies may increase by as much 6.7% and 1.6 months, respectively, with only a slight increase (< 0.4 months) in the quality-adjusted waiting time until transplantation.

A fatty acid synthase gene in Cochliobolus carbonum required for production of HC-toxin, cyclo(D-prolyl-L-alanyl-D-alanyl-L-2-amino-9, 10-epoxi-8-oxodecanoyl)

The fungal maize pathogen Cochliobolus carbonum produces a phytotoxic and cytostatic cyclic peptide, HC-toxin, of structure cyclo(D-prolyl-L-alanyl-D-alanyl-L-Aeo), in which Aeo stands for 2-amino-9,10-epoxi-8-oxodecanoic acid. Here we report the isolation of a gene, TOXC, that is present only in HC-toxin-producing (Tox2+) fungal strains. TOXC is present in most Tox2+ strains in three functional copies, all of which are on the same chromosome as the gene encoding HC-toxin synthetase. When all copies of TOXC are mutated by targeted gene disruption, the fungus grows and sporulates normally in vitro but no longer makes HC-toxin and is not pathogenic, indicating that TOXC has a specific role in HC-toxin production and hence virulence. The TOXC mRNA is 6.5 kb and the predicted product has 2,080 amino acids and a molecular weight of 233,000. The primary amino acid sequence is highly similar (45 to 47% identity) to the beta subunit of fatty acid synthase from several lower eukaryotes, and contains, in the same order as in other beta subunits, domains predicted to encode acetyl transferase, enoyl reductase, dehydratase, and malonyl-palmityl transferase. The most plausible function of TOXC is to contribute to the synthesis of the decanoic acid backbone of Aeo.

Calcifying fibrous pseudotumor of mediastinum--a case report

This report presents a case of calcifying fibrous pseudotumor arising in the posterior mediastinum of a 54-year-old woman. The histopathologic features of this case were identical to that of calcifying fibrous pseudotumor first designated in 1993. It is a distinctive benign fibrous lesion characterized by the presence of characteristics psammomatous or dystrophic calcification, abundant hyalinized collagen and lymphoplasmacytic cell infiltrate. Immunohistochemically most of the scattered fibroblasts were positive for vimentin, but not for CD-34 and cytokeratins, distinguishing it from solitary fibrous tumor of pleura and desmoplastic mesothelioma. The unusual site of the posterior mediastinum and the old age characterize this case.

A novel extensin gene encoding a hydroxyproline-rich glycoprotein requires sucrose for its wound-inducible expression in transgenic plants

A novel hydroxyproline-rich glycoprotein (SbHRGP3) that consists of two different domains is encoded by an extensin gene from soybean. The first domain (domain 1) located at the N terminus is composed of 11 repeats of Ser-Pro4-Lys-His-Ser-Pro4-Tyr3-His, whereas the second domain (domain 2) at the C terminus contains five repeats of Ser-Pro4-Val-Tyr-Lys-Tyr-Lys-Ser-Pro4-Tyr-Lys-Tyr-Pro-Ser-Pro5-Tyr-Lys-T yr- Pro-Ser-Pro4-Val-Tyr-Lys-Tyr-Lys. These two repeat motifs are organized in an extremely well-ordered pattern in each domain, which suggests that SbHRGP3 belongs to a new group of proteins having the repeat motifs of two distinct groups of dicot extensins. The expression of the SbHRGP3 gene increased with seedling maturation, and its expression was relatively high in the mature regions of the hypocotyl and in the root of soybean seedlings. An SbHRGP3-beta-glucuronidase (SbHRGP3-GUS) chimeric gene was constructed and expressed in transgenic tobacco plants. The expression of the SbHRGP3-GUS gene was not induced by wounding alone in transgenic tobacco plants; sucrose was also required. Expression was specific to phloem tissues and cambium cells of leaves and stems. In transgenic tobacco seedlings, SbHRGP3-GUS gene expression was activated by the maturation of the primary root and then inactivated; however, reactivation was specifically at the epidermis of the zone from which the lateral root was to be initiated. Its reactivation occurred just before the lateral root initiation. These results indicate that the SbHRGP3 gene in different tissues responds to different signals.

The loop B domain is physically separable from the loop A domain in the hairpin ribozyme

In order to understand the catalysis mechanism of the hairpin ribozyme, mutant ribozymes were constructed. The distance between the loop A domain and the loop B domain was extended by inserting various lengths of nucleotide linkers at the hinge region in cis mutants, or the domains were separated physically in a trans mutant. All the mutant ribozymes, including the trans mutant, could cleave substrate RNA at the predicted site. A cis mutant with a single nucleotide insertion exhibited cleavage activity about twice as high as that of the wild-type (wt) ribozyme. The insertion of 2-5 nucleotides (nt) gradually reduced the activity to the level of the wt ribozyme. Insertion of a longer linker, up to 11 nt, resulted in the reduction of activity to one half of that of the wt ribozyme. The ribozyme with a single nucleotide insertion at the hinge region seems to form a more suitable conformation for catalysis by three-dimensional fold-back of the loop B to loop A containing the cleavage site. The trans mutant, in which the A and B domains were physically separated, maintained a significant level of activity, suggesting that both domains are necessary for catalysis, but separable. These results demonstrate that interaction between the A and B domains results in catalysis.

Expression of sialic acid and polysialic acid in serogroup B Neisseria meningitidis: divergent transcription of biosynthesis and transport operons through a common promoter region

We studied capsule-defective (Cap-) serogroup B meningococcal mutants created through Tn916 or omega-fragment mutagenesis. The Cap- phenotypes were the results of insertions in three of four linked genes (synX, synC, and synD) involved in CMP-N-acetylneuraminic acid and polysialic acid capsule biosynthesis, and in ctrA the first of four linked genes involved in capsule membrane transport. Mutations in the CMP-N-acetylneuraminic acid biosynthesis genes synX and synC caused defects in lipooligosaccharide sialylation but not mutations in the putative (alpha2 -> 8)-linked polysialyltransferase (synD) or in ctrA. Reverse transcriptase PCR studies indicated that the four biosynthesis genes (synX to -D) and the capsule transport genes (ctr to -D) were separately transcribed as operons. The operons were separated by a 134-bp intergenic region. Primer extension of synX and ctrA demonstrated that transcription of the operons was divergently initiated from adjacent start sites present in the intergenic region. Both transcriptional start sites were preceded by a perfect -10 Pribnow promoter binding region. The synX to -D, but not the ctrA to -D, transcriptional start site was preceded by a sequence bearing strong homology to the consensus sigma 70 -35 promoter binding sequence. Both promoters showed transcriptional activity when cloned behind a lacZ reporter gene in Escherichia coli. Our results confirm the intrinsic relationship between polysialic acid capsule biosynthesis and lipooligosaccharide sialylation pathways in group B Neisseria meningitidis. Our study also suggests that the intergenic region separating the synX to -D and ctrA to -D operons is an important control point for the regulation of group B capsule expression through coordinated transcriptional regulation of the synX to -D and drA to -D promoters.

Chromosomal organization of TOX2, a complex locus controlling host-selective toxin biosynthesis in Cochliobolus carbonum

Race 1 isolates of the filamentous fungus Cochliobolus carbonum are exceptionally virulent on certain genotypes of maize due to production of a cyclic tetrapeptide, HC-toxin. In crosses between toxin-producing (Tox2+) and toxin-nonproducing (Tox2-) isolates, toxin production segregates in a simple 1:1 pattern, suggesting the involvement of a single genetic locus, which has been named TOX2. Earlier work had shown that in isolate SB111, TOX2 consists in part of two copies of a gene, HTS1, that encodes a 570-kD cyclic peptide synthetase and is lacking in Tox2- isolates. The genomic structure of TOX2 and the relationship between the two copies of HTS1 have now been clarified by using pulsedfield gel electrophoresis and physical mapping. In isolate SB111, both copies of HTS1 are on the largest chromosome (3.5 Mb), which is not present in the related Tox2- strain SB114. Two other genes known or thought to be important for HC-toxin biosynthesis, TOXA and TOXC, are also on the same chromosome in multiple copies. Other independent Tox2+ isolates also have two linked copies of HTS1, but in some isolates the size of the chromosome containing HTS1 is 2.2 Mb. Evidence obtained with Tox2+ -unique and with random probes is consistent with a reciprocal translocation as the cause of the difference in the size of the HTS1-containing chromosome among the Tox2+ isolates studied here. Physical mapping of the 3.5-Mb chromosome of SB111 that contains HTS1 using rare-cutting restriction enzymes and engineered restriction sites was used to map the chromosome location of the two copies of HTS1 and the three copies of TOXC. The results indicate that TOX2 is a complex locus that extends over more than 500 kb. The capacity to produce HC-toxin did not evolve by any single, simple mechanism.

Percutaneous endoscopic management of upper ureteral stricture size of stent

PURPOSE

We determined the optimal size (6F versus 14/7F) of stent after endoscopic surgery based on clinical data.

MATERIALS AND METHODS

Between 1989 and 1993 we performed percutaneous endopyelotomy and endoureterotomy in 40 cases of ureteropelvic junction or upper ureteral strictures. The causes of stricture were primary in 20 cases, tuberculosis in 9, previous operation in 6 and others in 5. After endoscopic management we placed 6F internal stents in 25 patients (13 in primary and 12 in secondary cases) or 14/7F endopyelotomy stents in 15 patients (7 in primary and 8 in secondary cases) for 6 to 8 weeks (average 54.2 days). Coexisting stones or infundibular strictures were managed simultaneously. All patients have been followed for a minimum of 7 months postoperatively (range 7 to 55, average 38).

RESULTS

Overall success rate was 84% (92.3 in primary and 75% in secondary cases) with the 6F stent and 93.3% (85.7% in primary and 100% in secondary cases) with the 14/7F endopyelotomy stent.

CONCLUSIONS

The small number of patients in each group did not reach statistical significance. However, there was a definite trend for better results with the use of 14/7F stents in patients with secondary stricture (100% versus 75%), although the difference in success rates between 6F and 14/7F stents was not significant statistically (p = 0.13).

Characterization and disruption of a gene in the maize pathogen Cochliobolus carbonum encoding a cellulase lacking a cellulose binding domain and hinge region

A gene, CEL1, in the maize pathogen Cochliobolus carbonum was identified using the cbh1-3 gene of Phanerochaete chrysosporium as a heterologous probe. The predicted product of CEL1, Cel1, is 62% identical and 71% similar to the product of cbh1-3 and 54 to 62% identical to five cellobiohydrolases from other filamentous fungi. The location of the polyadenylation site 221 bp downstream of the stop codon and the location of a single intron of 55 bp were identified by comparison of the sequences of genomic and cDNA copies of CEL1. The transcriptional start site was determined by rapid amplification of cDNA ends (RACE) to be 39 bp upstream of the putative translational start site. CEL1 mRNA abundance is high when C. carbonum is grown on cellulose or maize cell walls but is undetectable when grown on 2% sucrose or cellulose plus sucrose. Cel1 has a predicted signal peptide of 18 amino acids and therefore a mature size of 46.4 kDa. Like the product of cbh1-1 of P. chrysosporium, but unlike most other endoglucanases and cellobiohydrolases (including the predicted product of cbh1-3), Cel1 does not have a putative cellulose binding domain or associated hinge region. The codon bias of CEL1 is stronger than the bias of cbh1-1 and comparable to that of cbh1-3 and that of the C. carbonum genes PGN1 and XYL1, (encoding endopolygalacturonase and endo-xylanase, respectively). A strain of C. carbonum specifically mutated at CEL1 was produced by transformation with a truncated copy of CEL1. Integration and disruption of CEL1 in the mutant was confirmed by DNA and RNA blotting. Pathogenicity of the CEL1 mutant was indistinguishable from the wild-type, indicating that CEL1 by itself is not a critical disease determinant. Culture filtrates of C. carbonum grown on cellulose or maize cell walls had several cellobiohydrolase, endoglucanase, and beta-glucosidase activities that were separable by chromatofocusing, hydrophobic interaction, or ion-exchange high-performance liquid chromatography.(ABSTRACT TRUNCATED AT 250 WORDS)

A small cell osteosarcoma on the calcaneus--a case report

Small cell osteosarcoma is rare, representing 1-4% of all osteosarcomas. We experienced a case of small cell osteosarcoma in an 8-year-old girl on her calcaneus. Histologically, the tumor consists of small round cells that resemble those of Ewing's sarcoma, and variable foci of lacy osteoid formation between tumor cells. The rare location, histologic characteristics and differential diagnostic points are discussed.

Inactivation of the UAS1 of STA1 by glucose and STA10 and identification of two loci, SNS1 and MSS1, involved in STA10-dependent repression in Saccharomyces cerevisiae

It has been reported that two upstream activation sites, UAS1 and UAS2, exist in the 5' non-coding region of the STA1 gene of Saccharomyces cerevisiae var. diastaticus. Based on studies using a UAS1STA1-CYC1-lacZ fusion, we divided UAS1 into two subsites, UAS1-1 and UAS1-2. The activation of the CYC1 promoter by UAS1STA1 was repressed by glucose in the culture medium and by the STA10 gene. The MATa/MAT alpha mating type configuration did not, however, affect UAS1STA1 activation. The UAS1STA1-CYC1-lacZ expression system was used to study STA10 repression further. A mutant insensitive to STA10-dependent repression was isolated. This sns1 mutation was not linked to STA10 and partially overcame the repressive effect of STA10 at the transcriptional level. From a genomic library constructed in the UAS1STA1-CYC1-lacZ expression vector, the MSS1 locus (multicopy suppressor of sns1) was isolated. This suppression of the sns1 mutation by multiple copies of the MSS1 locus occurred at the transcriptional level. When a gene disruption experiment was performed to examine the effect of a mss1 mutation, the sns1 mss1 double mutants produced 4 times higher levels of STA1 transcripts in the presence of STA10 than did the sns1 strain. Data presented in this paper suggest that both SNS1 and MSS1 loci are involved in STA10-dependent repression.

Bone marrow findings before and after treatment with recombinant human erythropoietin in chronic hemodialyzed patients

The stimulating effect of rHuEPO on erythropoiesis has been shown in several studies, using bone marrow cell culture or animal models. To investigate the effect of rHuEPO on bone marrow findings in vivo, we studied the bone marrow cellularity, the myeloid: erythroid (M:E) ratio, an estimate of the number of megakaryocytes, any cytomorphologic or maturation abnormalities, and an estimate of the storage iron before and after 3 months of treatment with rHuEPO in 10 chronic hemodialyzed patients. Nine patients showed a slight or moderate decrease of erythropoiesis in bone marrow in comparison to normal bone marrow before rHuEPO treatment. The bone marrow cellularity was a mean of 28.5% and decreased in 8 out of 10 patients compared to normal values. However, megakaryopoiesis and granulopoiesis were normal. Three months of treatment with rHuEPO had increased erythropoiesis in all 10 patients, including one patient whose bone marrow proved to be normal erythropoiesis on baseline examination. The M:E ratio was significantly decreased from 4.0 +/- 1.2:1 to 2.4 +/- 1.1:1 (p < 0.005). The bone marrow cellularity was also increased in 9 patients, except in 1 patient whose specimen was inadequate for diagnosis, after 3 months of treatment with rHuEPO. On baseline examination of bone marrow, iron staining was undetectable in one, low in one, normal in 2 and high in 5 sections. According to grading, iron staining had decreased from 3.1 +/- 1.7 to 2.1 +/- 0.9 (p < 0.05).(ABSTRACT TRUNCATED AT 250 WORDS)

Tissue-specific and developmental regulation of a gene encoding a low molecular weight sulfur-rich protein in soybean seeds

A gene corresponding to a cDNA clone, SE60, encoding a low molecular weight sulfur-rich protein in soybean seeds was isolated from a soybean genomic library and characterized at the nucleotide level. The SE60 gene is interrupted by an intervening sequence of 694 bp in size. The 5' flanking region of the gene contained various regulatory sequences such as the RY repeat and CACA elements found in other seed protein genes of legumes. The SE60 gene encoded a preprotein of 75 amino acids, having a signal sequence of 28 amino acids at the N-terminus. The mature protein of 47 amino acids was basic and cysteine-rich. Northern blot analysis suggested that the SE60 gene is expressed in a tissue-specific and developmentally regulated manner during soybean seed development. The SE60 genes form a small multigene family composed of about four members in the soybean genome.

Liver function in Clonorchis sinensis-infected rabbits

Nine rabbits were fed with Clonorchis sinensis metacercariae (MC) and the blood samples chronologically obtained were analyzed biochemically. Rabbits infected by less than 100 flukes were grouped into Group I, and by 100-250 flukes into Group II. The serum level of alanine aminotransferase (ALT) was increased from 3 weeks after the infection of the metacercariae (AIM) and showed a peak at 8 weeks, and decreased from 12 weeks AIM. The serum level of aspartate aminotransferase (AST) was raised to 92.3 +/- 65.4 U/L at 3 weeks AIM and stayed high until 8 weeks, then lowered thereafter. The serum level of gamma-glutamyl transpeptidase (gamma-GT) was increased rapidly to the highest value (18.9 +/- 14.6 U/L) at 16 weeks AIM, and decreased to the control level after 20 weeks. The serum level of alkaline phosphatase (ALP) was headed down from the early infection to 52 weeks AIM. The serum cholesterol level was increased from 8 weeks and reached at a peak 16 weeks AIM, and decreased thereafter to the control level. It is suggested that serum ALT, AST, ALP and gamma-GT tests be useful to diagnose the early infection of C. sinensis.

The expression of beta 1 integrin and intercellular adhesion molecule-1 on mesangial cells and its modulation in glomerulonephritis

OBJECTIVES

This study was performed to observe the effects of conditioned media (CM) of cultured mononuclear cells (MNC) on the expression of beta 1 integrin and intercellular adhesion molecule(ICAM)-1 on mesangial cells and the modulation by TGF-beta, TNF alpha, or hydroxyl radical Also these were examined in anti-Thy mesangial proliferative GN (MsPGN) or puromycin aminonucleoside nephrosis(PAN).

METHODS

The expression of beta 1 integrin and ICAM-1 on mesangial cells was examined by ELISA and the modulation by TGF-beta, TNF alpha, or hydroxyl radical was investigated by using neutralizing antibody and dimethylthiourea. [.OH] scavenger.

RESULTS

The CM of MNC from Control suppressed the beta 1 integrin expression and thymidine incorporation and increased ICAM-1 expression on mesangial cells, compared to media alone. Especially the significant increase in ICAM-1 expression was reversed by anti-TNF alpha antibody. beta 1 integrin expression on mesangial cells was higher by the addition of CM of MNC in MsPGN than in Control, which was prevented by anti-TGF beta antibody or dimethylthiourea. ICAM-1 expression was not different among groups. Thymidine incorporation by adding CM of MNC was lower in MsPGN and PAN, which was mitigated by anti-TGF beta and anti-TNF alpha. Thus the ratio of the expression of ICAM-1 to thymidine incorporation was higher in MsPGN and PAN.

CONCLUSION

The expression of beta 1 integrin and ICAM-1, and the thymidine incorporation on mesangial cells are directly regulated by MNC, maybe through factors such as TGF beta or TNF alpha. In MsPGN, the overexpression of beta 1 integrin induced by MNC through TGF beta or hydroxyl radical on day 3 may be related to the pathogenesis.

Ventricular function after the arterial switch operation for transposition of the great arteries

The theoretical advantages of anatomical repair have resulted in the widespread use of the arterial switch operation for transposition of the great arteries. However, preservation of systemic ventricular performance and late functional results have not been well documented. To evaluate late postoperative ventricular function, we reviewed 53 consecutive patients undergoing arterial switch operation for transposition of the great arteries with or without a ventricular septal defect over the 8-year period from March 1985 to 1993. Forty-two patients had simple transposition of the great arteries and 11 patients had associated ventricular septal defects that were closed at operation. Mean age at operation was 1.8 months (range, 1 day to 36 months), and mean patient weight was 3.8 kg (range, 1.8 to 15.6 kg). All but 8 patients were neonates. There were six operative deaths (11.3%, 6/53) and two late deaths during a median follow-up of 23 months (range, 0.1 to 99.5 months). Actuarial survival at 8 years was 83% +/- 6%. Left ventricular outflow tract obstruction has not been identified, and 9 patients (20%, 9/45) have right ventricular outflow tract gradients exceeding 20 mm Hg, 3 of whom have required reoperation. Eighteen patients have mild neo-aortic valve regurgitation. All survivors are currently in New York Heart Association class I, and are in sinus rhythm. Systolic left ventricular function is well preserved with ejection fractions greater than 0.60 in all survivors followed up for more than 4 months (41 patients). Left ventricular end-diastolic volume index is elevated in only 1 patient, a patient who had pulmonary artery banding as a neonate.(ABSTRACT TRUNCATED AT 250 WORDS)

Effect of angiotensin converting enzyme inhibitor on collagen production by cultured mesangial cells

Cultured mesangial cells (MC) express renin mRNA and generate angiotensin I, supporting the action of local renin-angiotensin system. Also angiotensin II may act like a growth factor and was reported to increase collagen production (CP) in cultured MC. Angiotensin converting enzyme inhibitor is suggested to attenuate development and advancement of glomerulosclerosis, mainly with its hemodynamic effects. Therefore, we investigated the direct effects of enalapril (E) on CP by cultured MC. Rat MC were cultured in DMEM media alone, or containing high glucose (HG: 25 mM) or soluble immune complex (IC) prepared with bovine gamma globulin (BGG) and anti-BGG, with or without E (0.2 microgram/ml). CP was determined after 24 h by [3H] proline incorporation method. E significantly reduced CP by 43% in medium as compared with control (C) (C: 37,210 +/- 4,200 vs C + E: 21,350 +/- 5,080 cpm/well, p < 0.01). CP in medium increased in the presence of HG (123% of C) or IC (147% of C), which was, however, prevented with E (HG + E: 105% of C, IC + E: 116% of C). There were no differences of CP in cell layer between C (3,490 +/- 220 cpm/well) and C + E (3,340 +/- 190 cpm/well), and also no changes after addition of E in HG or IC groups. In conclusion, E directly attenuates CP by MC, even in the presence of HG or IC, independently of its hemodynamic effects.

Tumor necrosis factor alpha from peripheral blood mononuclear cells of IgA nephropathy and mesangial cell proliferation

BACKGROUND

To investigate the role of mononuclear cells and their products on rat mesangial cell proliferation, we evaluated the effect of peripheral blood mononuclear cells (PBMC) culture supernatant of patients with IgA nephropathy on rat mesangial cells 3[H]-thymidine uptake, and measured the concentration of cytokines in the supernatant to find out which cytokine in PBMC culture supernatant has a major influence on mesangial cell 3[H]-thymidine uptake.

METHODS

In ten patients with primary IgA nephropathy and 10 normal controls, PBMC were cultured with PHA (20 micrograms/ml) and con-A (10 micrograms/ml) for 24 hours, and supernatants were collected and stored at -70 degrees C until tested. Mesangial cell was cultured for 48 hours at a concentration of 10(4) cells/well with 1:2 or 1:10 diluted PBMC culture supernatant. 3[H]-thymidine uptake into rat mesangial cell was assayed after 18 hour culture. The cytokine concentrations of PBMC culture supernatant were measured by radioimmunoassay.

RESULTS

When 1:2 diluted PBMC culture supernatant was added, the supernatant of IgA nephropathy induced higher 3[H]-thymidine uptake into mesangial cell compared with that of normal controls. 3[H]-thymidine uptake induced by 1:2 diluted PBMC culture supernatant was significantly higher than that induced by 1:10 diluted supernatant of IgA nephropathy. The concentration of TNF-alpha in PBMC culture supernatant of the patients with IgA nephropathy was higher than that of normal controls and showed a good correlation with the mesangial cell 3[H]-thymidine uptake.

CONCLUSION

It is suggested that the mononuclear cell of IgA nephropathy may have the intrinsic property to produce more TNF-alpha which may be mitogenic to mesangial cells when stimulated with mitogens, and it may be related to the mesangial cell proliferation in IgA nephropathy.

Triple innominate osteotomy for hip stabilisation and transiliac leg lengthening after poliomyelitis

We reviewed our experience with a modified triple innominate osteotomy for hip instability and limb shortening due to poliomyelitis in 62 adolescent and adult patients, treated from 1973 to 1990. Their ages at surgery ranged from 12 years to 35 years (average 22.3). At a mean follow-up of 4 years (2 to 18) 59 of the patients (95.2%) had substantial improvement in hip stability, and all but one had radiological improvement as determined by the acetabular angle, centre-edge angle and acetabulum-head quotient. In 59 cases in which transiliac limb lengthening was attempted, the mean gain was 1.7 cm (0.6 to 3.0). When the abductor muscles had been partially paralysed, the operation produced an appreciable increase in power in 12 of the 39 hips examined.

[Worm recovery rate and small intestinal lesions of albino rats coinfected with Fibricola seoulensis and Metagonimus yokogawai]

Worm recovery rates and pathologic changes in small intestine of albino rats were observed after concurrent and challenge infections with metacercariae (MC) of Fibricola seoulensis and Metagonimus yokogawai, and compared with those of single infection groups. Albino rats in concurrent infection group were killed 20 days after feeding with 1,000 MC of each fluke. Rats in challenge infection group were fed with 1,000 MC of F. seoulensis and challenged by 1,000 MC of M. yokogawai 10 days after primary infection, then killed 10 days thereafter. In concurrent infection group, mean number of F. seoulensis and M. yokogawai recovered, 250 and 118 respectively, were similar to those of single infection groups. However, more flukes were collected from the duodenum and less flukes were from the ileum than from single infection group. In challenge infection group, the recovery rate of F. seoulensis was similar to that of single infection group and the distribution of the flukes was similar to that of concurrent infection group. Mean number of M. yokogawai, 69, was significantly lower than that of single infection group. Its distribution, however, extended to the duodenum and most of the flukes were recovered from the jejunum. In concurrent infection group, villi of the duodenum were more markedly thickened, fused and shortened than those in F. seoulensis single infection group. The crypt epithelium appeared to be hyperplastic and inflammatory cell infiltration into the villous stroma was mild. Villous atrophy in the jejunum and ileum was milder than in M. yokogawai single infection group. In challenge infection group, the findings were similar to those of concurrent infection group.(ABSTRACT TRUNCATED AT 250 WORDS)

A case of polymyositis in a patient with primary biliary cirrhosis treated with D-penicillamine

Although D-penicillamine has been used for many rheumatologic diseases, toxicity limits its usefulness in many patients. Polymyositis/dermatomyositis can develop as one of the autoimmune complications of D-penicillamine treatment, but its exact pathogenesis remains unclear. We report a patient with primary biliary cirrhosis, who developed polymyositis while receiving D-penicillamine therapy. We described the special clinical course of the patient. Patients receiving D-penicillamine therapy should be followed carefully for the development of autoimmune complications like polymyositis/dermatomyositis.

Motor recovery of the upper extremities in traumatic quadriplegia: a multicenter study

Clinicians need to know recovery of neurologic function in the upper extremities after traumatic quadriplegia to prognosticate function in self-care, to determine the effectiveness of various interventions, and to develop a comprehensive rehabilitation plan. This study was undertaken to determine the extent of recovery of key muscles of the arms in motor complete quadriplegic subjects. The hypothesis stated that patients with some motor power (grades 1.0 to 2.5/5) in muscles in the zone of partial preservation would recover at an earlier time and to a greater extent than those with no motor power (grade 0/5). One hundred fifty subjects, C4, C5, and C6 motor complete, were entered in the study within one week of injury from four centers. Serial muscle examinations of the biceps, wrist extensors, and triceps on the right and left sides were performed up to 24 months after spinal cord injury. The pattern of recovery in the key muscles of the 67 subjects with some motor power in the zone of partial preservation to grade 3/5 was significantly greater than the 83 subjects with no motor power (68% to 82% vs 14% to 36%, p less than .001) at three to six months postinjury. The plateau of the median manual muscle test score determined the extent of recovery and reached grade 4/5 in subjects with some motor power at three to six months. The pattern of recovery revealed more subjects with some motor power improved to grade 3/5 at all intervals earlier than those with no motor power (p less than .005).(ABSTRACT TRUNCATED AT 250 WORDS)

Intracellular localization of newly synthesized transferrin receptors in the peripheral sheep reticulocyte

In this paper, we provide evidence for an incompletely glycosylated transferrin receptor (TfR) which is not transported to the plasma membrane in the sheep reticulocyte. Cleveland peptide maps of the native (preexisting) TfR and [35S]methionine-labeled TfR were different. If the receptors were deglycosylated before mapping, the peptides were identical. There was preferential binding of the [35S]TfR to Con A-Sepharose, indicating the existence of a higher density of high mannose chains on the 35S-labeled TfR. Moreover, when total [3H]mannose-labeled glycopeptides from reticulocytes were separated on a column of Bio-Gel P6, the [3H]mannose was associated with endoglycosidase H-sensitive high mannose or hybrid oligosaccharides, but not with complex sugars. After Percoll density gradient centrifugation, the [35S]TfR peaked in a fraction which separated from the bulk of the native TfR. The transmembrane glycoproteins, Band 3 and mature glycophorins, are not synthesized in the sheep reticulocyte. It appears that the reticulocyte, at this stage of red cell development, has lost the vesicles and/or proteins which are required to transport proteins from the site of translation to the cell surface.

A case of herpes zoster myelitis: positive magnetic resonance imaging finding

A 33-year-old man developed a progressive myelopathy after a characteristic skin lesion of herpes zoster involving the right C3 and C4 dermatomes. The lesions were recognizable in the T2-weighted image of the magnetic resonance imaging (MRI) as increased signal intensities throughout the long segments of the spinal cord with maximal in the cervical portion, which was compatible with the pathological findings reported in autopsy studies.

Hematite Nanospheres of Possible Colloidal Origin from a Precambrian Banded Iron Formation

Exceptionally small spheres (nanospheres) of hematite (diameters between 120 and 200 nanometers) occur in the Marra Mamba Iron Formation of the Hamersley Basin, Australia. The nanospheres are clustered into small aggregates and may have formed by structural ordering and dehydration of colloidal iron hydroxide particles. Individual spheres consist of numerous thin, curved hematite platelets surrounding a central void that is approximately half the diamter of the sphere; this texture suggests that they formed by a volume reduction of the original colloidal particles by approximately 12.5%. The occurrence of hematite nanospheres supports the hypothesis that some ofthe iron was deposited colloidally during the development ofbanded iron formations, approximately 2.5 billion years ago.

Scrotal fistula from urethro-vasal reflux in paraplegia

A case is presented of a paraplegic in whom urethro-vasal reflux and scrotal fistula developed. Urodynamics testing showed a hyperreflexic bladder with detrusor-external sphincter dyssynergia.

A case report: carcinoma of the gastric stump after Billroth II resection

Carcinoma of the gastric stump as a late complication for resection of benign disease is a well recognized clinical entity.

The risk of stump carcinoma, at least in Western Europe, is estimated to be increased twofold compared with the normal population.

But in Korea there has been one report. Recently we experienced a case of carcinoma of the stump which developed about 20 years after a gastro-jejunostomy for a duodenal ulcer.