Reversible esophageal motility disorder in a patient with sarcoidosis

Hysterosalpingo-contrast sonography was compared with sonographically controlled selective tubal catheterization (STC) in 26 infertile women who complained of infertility. Both procedures were carried out on a single examination date. A group of 10 patients first underwent hysterosalpingo-contrast sonography followed by STC, while 16 first had STC followed by hysterosalpingo-contrast sonography. The main outcome measure was tubal patency. A total of 52 Fallopian tubes was assessed. Hysterosalpingo-contrast sonography showed 39 tubes (75%) and STC 46 (89%) to be patent, 13 tubes (25%) and six tubes (12%) were diagnosed to be proximally occluded, by means of hysterosalpingo-contrast sonography and STC respectively. Concordant diagnosis with both methods was made in 43 of 52 tubes (83%). When hysterosalpingo-contrast sonography was followed by STC, the concordance rate was 85%. When STC was followed by hysterosalpingo-contrast sonography, the concordance rate was 81%. In one patient the diagnosis of proximal occlusion of one tube as determined by hysterosalpingo-contrast sonography and STC had to be correlated in laparoscopy. In a patient, who after hysterosalpingo-contrast sonography and STC, was suspected to have bilateral proximal occlusion of the tubes, considerable bilateral proximal stenosis and distal occlusion was documented at laparoscopy. In conclusion, sonographically controlled STC may correct a misdiagnosis in cases where hysterosalpingo-contrast sonography leads to the finding of proximal tubal obstruction. The combination of hysterosalpingo-contrast sonography and STC as an out-patient investigation method for tubal patency assessment in infertile women avoids anaesthesia and radiation. For this reason we recommend the combination of sonographically controlled STC with hysterosalpingo-contrast sonography, at least in cases where proximal tubal occlusion is suspected after hysterosalpingo-contrast sonography. The influence of the order in which the two methods are used on the results of both should be investigated in a randomized study.     

Perineurial malignant peripheral nerve sheath tumor (MPNST): a clinicopathologic, immunohistochemical, and ultrastructural study of seven cases

Most malignant peripheral nerve sheath tumors (MPNST) are schwannian in nature. The pathologic features of MPNST with perineurial cell differentiation remain to be characterized. To determine the clinicopathologic, immunohistochemical, and ultrastructural characteristics of perineurial MPNST, 121 MPNST from the Mayo Clinic Tissue Registry were examined. Of these 23 spindle cell tumors with long processes disposed in whorls or storiform patterns, features typical of perineurioma, were studied. On the basis of immunohistochemistry (epithelial membrane antigen+/S-100-), 5 perineurial MPNST were identified among 23 tumors selected. These and two previously characterized perineurial MPNST are the subject of this study. None of seven tumors was associated with NF-1. Patients included five males and two females ranging in age from 11 to 83 years (mean, 45.7 years). The tumors measured 1.5 to 30 cm (mean, 9.1 cm) and arose in the extremities (two), trunk (two), face (one), mediastinum (one), and retroperitoneum (one). Only one tumor was nerve associated (phrenic nerve). All tumors were surgically removed. No encapsulation or neurofibroma components were noted. Necrosis was seen in three lesions. Four tumors were classified as high-grade malignant and three as low grade. Mitotic indices varied from 1 to 85/10 high-power fields (median, 16). Immunoreactivities included epithelial membrane antigen (100%), vimentin (100%), Leu-7 (57%), and CD34 (14%). Stains for S-100 protein, muscle markers, and cytokeratin were nonreactive. Ultrastructurally, perineurial-like cells were noted in three tumors and cells intermediate between perineurial and Schwann cells in one. Four tumors recurred and two metastasized; no deaths of disease were noted at follow-ups of 28 to 98 months (mean, 66.9). In conclusion, 4% of MPNST show perineurial cell differentiation. An NF-1 association has yet to be described. Nerve involvement is infrequent. Their immunophenotype (epithelial membrane antigen+/S-100-) frequently indicates ultrastructural perineurial differentiation. The prognosis of perineural MPNST appears to be more favorable than that of conventional MPNST.     

Identification of fur, aconitase, and other proteins expressed by Mycobacterium tuberculosis under conditions of low and high concentrations of iron by combined two-dimensional gel electrophoresis and mass spectrometry

Iron plays a critical role in the pathophysiology of Mycobacterium tuberculosis. To gain a better understanding of iron regulation by this organism, we have used two-dimensional (2-D) gel electrophoresis, mass spectrometry, and database searching to study protein expression in M. tuberculosis under conditions of high and low iron concentration. Proteins in cellular extracts from M. tuberculosis Erdman strain grown under low-iron (1 microM) and high-iron (70 microM) conditions were separated by 2-D polyacrylamide gel electrophoresis, which allowed high-resolution separation of several hundred proteins, as visualized by Coomassie staining. The expression of at least 15 proteins was induced, and the expression of at least 12 proteins was decreased under low-iron conditions. In-gel trypsin digestion was performed on these differentially expressed proteins, and the digestion mixtures were analyzed by matrix-assisted laser desorption ionization time-of-flight mass spectrometry to determine the molecular masses of the resulting tryptic peptides. Partial sequence data on some of the peptides were obtained by using after source decay and/or collision-induced dissociation. The fragmentation data were used to search computerized peptide mass and protein sequence databases for known proteins. Ten iron-regulated proteins were identified, including Fur and aconitase proteins, both of which are known to be regulated by iron in other bacterial systems. Our study shows that, where large protein sequence databases are available from genomic studies, the combined use of 2-D gel electrophoresis, mass spectrometry, and database searching to analyze proteins expressed under defined environmental conditions is a powerful tool for identifying expressed proteins and their physiologic relevance.     

Actin disassembles reversibly during electrically induced recycling of synaptic vesicles in cultured neurons

We have studied depolarization-induced regulation of actin assembly in exocytotically active areas of dissociated chick sympathetic neurons. Active areas were identified with the fluorescent dye FM1-43 which labels synaptic vesicles that recycle in these regions. Exocytosis (electrically stimulated) was monitored in real time through depletion of FM1-43 fluorescence. To study depolarization-induced disassembly of actin in the FM1-43-stained regions, the cells were fixed after different periods of depolarization and stained with rhodamine phalloidin, which binds preferentially to the filamentous form of actin. In active regions, actin disassembles and reassembles during continuous 2 min depolarization. Actin disassembly that occurs after the first 25 s of depolarization was detected by a reduction in rhodamine phalloidin staining and confirmed by correlative electron microscopy. Immunogold staining revealed that actin is abundant throughout resting terminals. In some experiments, actin filaments were stabilized by loading cells with unlabelled phalloidin before stimulating secretion. Stabilizing the filaments does not alter the initial release but strongly reduces the release rate at later stages. These data are consistent with a model in which partial disassembly of actin filaments is necessary for facilitating the transport of vesicles within the terminal and reassembly is necessary for limiting that movement.     

Deformity correction and arthrodesis of the midfoot with a medial plate

Nine feet in eight patients undergoing tarsometatarsal (Lisfranc) or other midfoot arthrodeses for posttraumatic or degenerative arthritis were reviewed retrospectively. All patients were treated using a medial one-third tubular plate spanning the midfoot joints to be fused. Three feet underwent fusion in situ while six feet underwent correction of residual planus, planovalgus, or cavovarus deformity at the time of fusion. All patients achieved fusion within 12 weeks. A good or excellent result was achieved in seven of nine feet. There was no radiographic or clinical evidence of pseudarthrosis or medial hardware failure in any patient. No patient to date has required hardware removal for a painful or prominent implant. The talus first metatarsal angle was improved an average of 15.5 degrees in the lateral plane and 10 degrees in the AP plane in patients undergoing deformity correction. The technique of using a medial plate for midfoot arthrodesis allows for reliable fusion in patients who require salvage for midfoot arthritis. This technique also allows for correction of deformity in patients with residual midfoot deformity.     

Complications of spongiosa harvesting of the ilial crest. A retrospective analysis of 1,191 cases

We analyzed retrospectively 1191 cases of bone graft harvesting of the iliac crest which had been performed at our hospital between 1982 and 1991. There was an operative revision rate of 2.8%. For further study, we analyzed the clinical reports of all autograft (iliac crest) donors in a representative year (1991) and re-examined all those who still had symptoms. A total of 104 grafts were taken from 97 patients. Of these, 18 developed postoperative complications (19.6%), such as hematoma, which could usually be treated with local procedures such as aspiration. The rate of hematoma tended to be lower in those patients who had received a local coagulant, but this was not significant. Of the patients 55% still had problems 1 year after operation at the time of re-examination, but in most cases they were minor, for example, local irritation or discomfort. Serious problems developed in those patients who had a palpable defect of the iliac crest. We advise using local coagulants to decrease the rate of postoperative complications, although we cannot statistically prove the effect. When large grafts are harvested, the iliac crest should be reconstructed for better long-term results.     

Influence of iron-limited continuous culture on physiology and virulence of Legionella pneumophila

A virulent strain of Legionella pneumophila serogroup 1, subgroup Pontiac, was grown in continuous culture at a constant growth rate under iron-replete and iron-limited conditions. Iron limitation was achieved by the removal of ferrous sulfate and hemin from the chemically defined medium. Residual contaminating iron, 0.45 microM, was sufficient to support iron-limited growth. Typical iron-replete cultures metabolized 3.3 microM iron. Serine provided the principal source of carbon and energy for both cultures, although iron-replete cultures also depleted a number of other amino acids. There was a 40% decrease in culture biomass under iron-restricted conditions. Iron limitation did not significantly affect carbohydrate metabolism, with the molar growth yield for carbon (Ycarbon) comparable for both cultures. However, under iron-limited conditions a sixfold increase in Yiron correlated with a significant decrease in the iron content of the biomass, as the culture utilized the available iron more efficiently. Highly pleomorphic iron-replete cultures became uniform cultures of short fine rods when adapted to iron-deficient conditions. In addition to the morphological and physiological changes, iron limitation had a critical effect on culture virulence. The virulence of this strain was significantly (P < 0.05) reduced when the culture was subjected to iron-limited conditions. This phenomenon was reversible, with a significant increase in culture virulence upon reversion to iron-replete conditions. When compared in an in vitro macrophage assay, the number of culturable avirulent iron-limited cells located intracellularly after infection was significantly lower than for the virulent replete and control cultures. These results further support the role of environmental parameters in regulating the virulence of L. pneumophila.     

Angiotensin-converting enzyme gene polymorphism in non-insulin dependent diabetes mellitus and its relationship with diabetic nephropathy

The effects of prolactin (PRL) on proliferation of cultured human uterine leiomyoma-derived smooth muscle cells (SMC) and its mechanism of action were investigated. PRL stimulated DNA synthesis and the expression of PRL receptor was identified by ribonuclease protection assay. Moreover, the regulation of mitogen-activated protein (MAP) kinase by PRL in leiomyoma-derived SMC was investigated. PRL stimulated MAP kinase activity, as detected by 32P incorporation into MAP-2, in a dose-dependent manner. PRL also rapidly stimulated MAP kinase phosphorylation as detected by in vivo phosphorylation using 32P labeling and phosphotyrosine immunoblotting. These results suggest that PRL stimulates the proliferation of human leiomyoma cells via the MAP kinase cascade.     

The stress-activated protein kinase pathway mediates cell death following injury induced by cis-platinum, UV irradiation or heat

BACKGROUND: Stimuli that stress cells, including inflammatory cytokines, ultra-violet irradiation, DNA-damaging chemotherapeutic drugs and heat shock, stimulate a recently identified cytoplasmic signaling system that is structurally related to the mitogen-activated protein kinase pathway. This pathway consists of a cascade of protein kinases including stress-activated protein kinase (SAPK), also termed Jun N-terminal kinase (JNK), and two kinases that activate it, MEKK and SEK/MKK4. Despite rapid progress in delineating the components of this pathway, the cellular consequence of its activation remains to be defined. RESULTS: We have screened cells for defects in SAPK signaling and identified a cell line, previously characterized for its thermotolerance properties, as being more refractive to SAPK activation induced by heat stress than its thermosensitive parental line. Stable expression of dominant inhibiting SEK mutants in thermosensitive parental cells specifically and effectively blocked SAPK activation after heat shock. These lines also became markedly resistant to the cytocidal effects of thermal stress, confirming the phenotype of the thermotolerant line. These cell lines defective in SAPK activation were also resistant to the lethal effects of the DNA-damaging drug cis-platinum. CONCLUSIONS: Experimentally induced stable blockade of SAPK activation in cells with normal thermosensitivity is sufficient to confer resistance to cell death induced by diverse stimuli including heat and the chemotherapeutic agent cis-platinum. These results suggest that activation of the SAPK pathway by diverse cell stressors plays a critical part in mediating the toxicity of these treatments and inducing cell death. SAPK activation in this context could broadly influence cellular response to stress, modulate apoptosis during development or determine the clinical response of tumor cells to cytotoxic therapies.