Rifampicin: an inhibitor of Xp12-specific protein phosphorylation in Xanthomonas oryzae pv. oryzae

Phosphorylation of the three Xp12-specific phosphoproteins was drastically reduced by rifampicin, an antibiotic that specifically inhibits the host-cell RNA polymerase. However, this inhibitory effect could not be found in spontaneous mutants of Xanthomonas oryzae pv. oryzae whose RNA polymerase are resistant to the drug. The inhibitory effect of rifampicin treatment also resulted suppression of the Xp12 multiplication cycle. This implies the physiological significance of this effect and supports our previous prediction that phosphorylation plays an important role in the life cycle of Xp12. The acid- and alkali-labile character of the Xp12-specific phosphoproteins and the chemical stability of the phosphoryl linkages show that the corresponding protein kinase catalyzes the formation of an acyl phosphorylation. Subsequent fractionation of cell lysate revealed that the phosphoproteins were located in the periplasm. Actinomycin D, which affects transcription through DNA condensation rather than its binding to RNA polymerase, was not able to cause the inhibition effect. On the other hand, cerulenin was found to reduce the acyl phosphorylation which hints at a possible role of cell membrane in the phosphorylation. Here we present the evidence for the functional involvement of the rifampicin treatment on protein phosphorylation. A possible mechanism of rifampicin on the alternation of acyl phosphorylation is proposed.

Acquired generalized hypohidrosis/anhidrosis with subclinical Sjögren's syndrome: report of a case with diffuse syringolymphoid hyperplasia and lymphocytic sialadenitis

The pathogenesis and the underlying pathologic changes of acquired generalized hypohidrosis/anhidrosis (AGHA) are largely unknown. We studied a case of AGHA in a young woman suffering from heat intolerance and progressive loss of sweating. Pathologic study of affected skin revealed unique syringolymphoid hyperplasia with T cell infiltration, suggesting a T cell-mediated autoimmune disease. The patient also had subclinical Sjögren's syndrome and diffuse hair loss. The pathogenesis of the latter two conditions is believed to be related to the patient's AGHA.

Embryonal rhabdomyosarcoma of the uterine corpus mistaken for small cell carcinoma: a case report

Pure rhabdomyosarcomas of the female genital tract mostly occur in infancy and childhood, in the form of sarcoma botryoides (a variant of embryonal rhabdomyosarcoma), with vagina and cervix as typically involved sites. Such tumors rarely occur in the uterine corpus and cervix of adults. We would like to report a pure embryonal rhab-domyosarcoma of the uterine corpus that arose in a 31-year-old, gravida 1, para 1, female patient with widespread bony metastasis, and which was originally mistaken for metastatic small cell carcinoma to bone marrow.

Rapid inhibition of protein histidine phosphorylation by UV-irradiation in Xanthomonas oryzae pv. oryzae

Exposure of Xanthomonas oryzae pv. oryzae cells to 254 nm UV radiation resulted in an alteration of protein phosphorylation. Labelling of the phosphohistidine-containing proteins with molecular masses of 81 and 32 kDa, named p81 and p32, was rapidly reduced following UV irradiation in the early exponential cells, but the decrease was not detected in mid-exponential cells. Mitomycin C, a DNA replication inhibitor, and rifampicin, a drug generally used to inhibit RNA synthesis and DNA replication, were also found to reduce the histidyl phosphorylation. However, this alteration of protein phosphorylation was not hindered by chloramphenicol treatment. A possible role for these histidyl phosphoproteins in sensing UV light is proposed.

Richter's syndrome: report of a case

A 42-year-old male presented with generalized massive lymphadenopathy, fever, weight loss and numerous cutaneous nodules. Peripheral blood examination showed lymphocytosis with small lymphocytes, and immunophenotyping revealed B-cell chronic lymphocytic leukemia (CLL). Cytogenetic analysis of bone marrow aspirate revealed a clonal abnormality of chromosome 11. Lymph node biopsies showed a B-immunoblastic lymphoma. A diagnosis of Richter's syndrome (RS) was made. The patient did not respond to doxorubicin, cyclophosphamide, vincristine and prednisolone (CHOP) and died of progressive disease with pneumonia and respiratory failure 9 months later. CLL is not common among Chinese people and RS is extremely rare.

Recurrence of Fusarium solani abscess formation in an otherwise healthy patient

Fusarium spp. are usually considered opportunistic fungi in humans. A case of Fusarium solani abscess formation of the foot in an immunocompetent patient in whom recurrence occurred even after intravenous amphotericin B treatment is presented here.

Clear cell papulosis: report of three cases of a newly recognized disease

BACKGROUND

Clear cell papulosis is a newly described disease. Since the first report in 1987, no other cases have been reported.

OBJECTIVE

Our purpose was to describe three more newly identified cases that further characterize this disease.

METHODS

Formalin-fixed and paraffin-embedded biopsy specimens were used for histochemical and immunohistochemical studies.

RESULTS

The three patients included two boys and, for the first time, a girl. All three had multiple white papules on the lower part of the abdomen, with or without scattered lesions along the milk lines bilaterally. The main histopathologic finding was the presence of clear cells scattered mainly among the basal cells of the acanthotic epidermis. The clear cells were variably stained by mucicarmine, colloidal iron, alcian blue (pH 2.5), periodic acid-Schiff, the anticytokeratin antibody AE1, carcinoembryonic antigen, epithelial membrane antigen, and gross cystic disease fluid protein-15.

CONCLUSION

Clear cell papulosis is a unique clinicopathologic entity. The clear cells were confirmed to be sweat gland secretory cells by their positive immunostaining with gross cystic disease fluid protein-15. The latter was also present in eccrine sweat gland coil cells. However, whether the clear cells were eccrine or apocrine secretory cells could not be determined.

Kimura's disease and angiolymphoid hyperplasia with eosinophilia: new observations from immunohistochemical studies of lymphocyte markers, endothelial antigens, and granulocyte proteins

Kimura's disease (KD) typically presents as large subcutaneous masses in young Oriental males. It is characterized by deep inflammation with vascular proliferation, lymphocytic nodules with subcutaneous germinal centers, fibrosis, and edema. In comparison, angiolymphoid hyperplasia with eosinophilia (AHLE) occurs in all races and the lesions usually are smaller and more superficial. The causes of these two diseases are debated. We compared histologic features of 4 cases of KD with 22 cases of ALHE and studied expression of endothelial antigens and lymphocyte markers as well as localization of eosinophil, mast cell, and neutrophil granule proteins in lesional tissue. T-cell lymphoid aggregates with well-formed B-cell germinal centers occurred in KD, and nodular and diffuse T-cell infiltration with small B-cell clusters occurred in ALHE. Endothelial proliferation was more pronounced in KD, lacking the atypical histiocytoid endothelial cells characteristic of ALHE. Many intact eosinophils infiltrated lesions in both diseases, although KD had less extracellular granule protein deposition than ALHE. Intact mast cells were seen in both diseases. There was neutrophil elastase staining of occasional scattered intact cells but no extracellular deposition. Compared with KD, ALHE is more varied in its clinical, histopathologic, and immunohistochemical features.

Kikuchi's disease (histiocytic necrotizing lymphadenitis). A clinicopathologic study of 79 cases with an analysis of histologic subtypes, immunohistology, and DNA ploidy

We conducted a clinicopathologic study of 79 cases of Kikuchi's disease. Our results confirmed that Kikuchi's disease is a distinctive type of necrotizing lymphadenitis that affects primarily the cervical lymph nodes of young adults and has a self-limited clinical course. However, female predominance was not as striking as heretofore reported. A low, but possible, recurrence rate of 3.3% was documented. Extranodal cutaneous involvement occurred in one patient who had a more severe and protracted clinical course. Classification of the histopathologic changes into three histologic types was proposed: proliferative, necrotizing, and xanthomatous types. These three types differed in certain aspects of their clinical features. Immunohistologic analysis revealed that the predominant cells of the lesions were various types of histiocytes, including the enigmatic plasmacytoid monocytes. A variable number of CD8(+) T cells correlating with the duration of the disease was detected. B cells were nearly absent, and only an insignificant number of OPD4(+) T cells was present. Eight cases studied by the flow cytometric DNA analysis all showed a diploid DNA content. Although the histologic changes of Kikuchi's disease were variable, the findings were sufficiently distinctive to permit accurate diagnosis. Malignant lymphoma and especially lupus lymphadenitis can be mistaken for Kikuchi's disease; thus differentiation is crucial.

Absence of p53 gene mutation and infrequent overexpression of p53 protein in hepatoblastoma

Ten cases of hepatoblastoma were studied for overexpression of p53 protein by immunohistochemistry and for possible p53 gene mutation by single strand conformation polymorphism (SSCP) analysis and direct DNA sequencing of the polymerase chain reaction products. Only one case of the macrotrabecular type at stage IV showed overexpression of p53 protein. No DNA mobility shift was found in any of these cases studied by SSCP analysis. DNA sequencing performed on the case showing overexpression of p53 protein revealed no mutation within exons 5 to 8. The associated adrenal cortical carcinoma of the same case also showed overexpression of p53 protein, but no mutation of the p53 gene. These results indicate that mutation of the p53 gene is infrequent in hepatoblastoma. This observation supports the view that mutation of the p53 gene is not as important in the oncogenesis of childhood neoplasms as in adult cancers.

Characterization of an open reading frame involved in site-specific integration of filamentous phage Cf1t from Xanthomonas campestris pv. citri

Cf1t is a single-stranded DNA filamentous phage; a 1.9-kb segment of DNA from Cf1t was found to be responsible for site-specific integration into Xanthomonas campestris pv. citri (XW47), in the absence of any Xanthomonas origin of replication. Deletion analysis and introduction of amber stop codons into this fragment from Cf1t revealed an open reading frame (ORF344) which was involved in the integration function. The predicted amino-acid sequence of ORF344 bears no homology with conserved sequences of the integrase family.

Abnormal growth induced by expression of HBsAg in the secretion pathway of S. cerevisiae pep4 mutants

The toxicity of HBsAg in the secretion pathway of pep4 strains can be progressively reduced in modified SD media containing lower concentrations of ammonium sulphate. A procedure, combining a reduction of ammonium sulphate concentration in SD media with the disruption of the PEP4 gene of the host strain, was developed to enrich transformants which are not inhibited by HBsAg expressed in the secretion pathway. Abnormal growth of these non-inhibited transformants is characterized by the enlargement of cell morphology, a transition to pseudohyphal-like growth in nitrogen-starved media, an increase in HBsAg particle production, and the enhancement of growth rate in liquid media. This suggests a new approach to overcoming the toxicity of heterologous protein in the yeast secretion pathway.

Prolongation of intraventricular conduction time associated with fatal [correction of fetal] impairment of defibrillation efficiency during treatment with class I antiarrhythmic agents

To test whether fatal deterioration of defibrillation efficiency during antiarrhythmic therapy can be prevented by avoiding extreme decrease in ventricular prevented by avoiding extreme decrease in ventricular conduction or toxic plasma drug levels, we determined the defibrillation threshold (DFT) before and during infusion of incremental doses of disopyramide (n = 8), mexiletine (n = 9), or flecainide (n = 9) in anesthetized dogs. Disopyramide did not alter DFT [from 4.4 +/- 1.5 to 4.4 +/- 1.6 J (3.1 +/- 1.2 micrograms/ml)]. Mexiletine tended to increase DFT [from 4.6 +/- 1.2 to 6.1 +/- 2.0 J (1.8 +/- 0.6 micrograms/ml); p < 0.05], and defibrillation eventually was unsuccessful in 3 of the 9 dogs. Although the plasma mexiletine level before refractory fibrillation was far beyond the human therapeutic range, prolongation of intraventricular conduction time (CT) was moderate (16 +/- 3%). Flecainide increased DFT from 4.2 +/- 1.3 to 6.1 +/- 1.5 J at a plasma level of 1.04 +/- 0.37 micrograms/ml (p < 0.0005). In 3 of 5 dogs that developed refractory fibrillation, plasma flecainide level before terminal ventricular fibrillation (VF) was not toxic, but prolongation of CT in the 5 dogs was remarkable (30 +/- 9%). Thus, VF resistant to defibrillation is not necessarily associated with both toxic plasma drug level and remarkably decreased conduction. Reliability of these valuables as indicators of fatally deteriorated defibrillation efficiency may vary among antiarrhythmic agents.

Attenuation of antifibrillatory effects of lidocaine by its metabolite, glycylxylidide: application of modulated receptor hypothesis

Lidocaine, one of the drugs effective in treating ventricular arrhythmias in acute myocardial infarction (AMI), sometimes loses its efficacy after prolonged administration, possibly owing to the counteraction of glycylxylidide, one of the metabolites of lidocaine, through modulation of binding of lidocaine to sodium channels. To determine whether glycylxylidide interferes with the antiarrhythmic action of lidocaine, we compared the antifibrillatory effects of lidocaine, glycylxylidide, and their combination in 14 anesthetized open-chest dogs. Although glycylxylidide alone prolonged intraventricular conduction time (CT) and did not affect ventricular effective refractory period (VERP), it had different effects when added to lidocaine; i.e., it had no effect on intraventricular conduction time but shortened VERP. Although glycylxylidide alone did not change ventricular fibrillation threshold (VFT), the increase in VFT induced by lidocaine was decreased by addition of glycylxylidide, possibly as a result of competition for the same cardiac sodium channels between lidocaine and glycylxylidide with similar onset but different offset kinetics, which may explain, at least in part, the drug-resistance phenomena that ensue from prolonged lidocaine administration.

Immunohistochemical analysis of dermal mononuclear cell infiltrates in cutaneous lupus erythematosus, polymorphous light eruption, lymphocytic infiltration of Jessner, and cutaneous lymphoid hyperplasia: a comparative differential study

Cutaneous lupus erythematosus (LE), polymorphous light-eruption (PMLE), lymphocytic infiltration of Jessner (LIJ), and cutaneous lymphoid hyperplasia (CLH) are often difficult to differentiate from one another by light microscopic examination. We conducted an immunohistochemical analysis of the mononuclear cell infiltrates in 13 LE, 12 PMLE, 10 LIJ, and 13 CLH with various antibodies. Antibodies L26, UCHL1, and S100 achieved statistically significant differences among the four diseases, but because of the overlaps in the number of UCHL1(+) T cells and S100 protein (+) cells in individual cases, these two antibodies were not useful. Only CLH could be distinguished from LE, PMLE, and LIJ by a greater number of CD20(+) B cells. The latter three conditions could not be differentiated. Contrary to previous reports, plasmacytoid-monocytes were not found to be increased in LIJ for the differentiation of the latter from LE and PMLE. Our results support the conclusion that CLH is a reactive lymphoid hyperplastic process with proliferation of both B and T cells, whereas the T cell was the predominant cell type in the infiltrates of LE, PMLE, and LIJ, indicating that they were related to T cell disorders. The histiocyte was only a minor component cell. The plasmacytoid monocyte in general was not significantly present in all four conditions, but relatively more plasmacytoid monocytes were present in CLH.

A long lytic cycle in filamentous phage Cf1tv infecting Xanthomonas campestris pv. citri

In this study the lytic cycle of a filamentous phage is reported. Under normal laboratory cultivation conditions a virulent form could spontaneously and easily arise from a temperate phage. The virulent one could superinfect cells containing Cf1t lysogen. Therefore, we have named it Cf1tv. In a colony formation assay using cells from an infected culture, two types of colonies were observed, small and large. It could be proven that the formation of small colonies is the result of killing during Cf1tv infection. The number of small colony forming units (cfu) increased with infection time and reached a maximum at 16 h after infection, then dropped to the initial cell concentration at 28 h after infection; 28 h were required to kill all infected cells. Large colonies contained uninfected or phage-resistant cells, but no lysogenic cells. Bacterial death was further confirmed by a microculture assay. At 2 h after infection, normal-dividing cells (cfu giving large colonies) contained about 40% of Cf1tv-infected cells, then the percentage decreased with infection time. Slow-dividing cells (infected cfu giving small colonies) initially contained 55% of cells; this percentage increased slightly at 4 h after infection, then decreased at 8 h after infection. Non-dividing cells initially contained 5% of infected cells, then their numbers rapidly increased with time after infection. The cell division was seriously affected and finally stopped. During one-step growth, the latent period was 30 min and there was no burst; phages were released at 30 min after infection and the rate of release increased gradually with time after infection. Phage DNA integration into host chromosome could not be observed.

Anticentromere antibodies (ACA): clinical distribution and disease specificity

Sera from 3528 patients with autoimmune disease, and non-autoimmune disease, and 500 normal individuals were studied for the presence of anticentromere antibodies (ACA) by indirect immunofluorescence on HEP-2 cells. Sixty-seven specimens were identified showing discrete speckled staining: 55 (82.1%), 11 (16.4%), and one (1.5%), were from patients with autoimmune disease, non-autoimmune disease and normal control subjects, respectively. These ACA were present frequently in CREST syndrome (55%), Raynaud's disease (29.6%) and primary biliary cirrhosis (30%). Only 16.4% of the antibody positive patients carried a clinical diagnosis of CREST, which means that ACA are not specific for CREST syndrome. High antibody titre persisted irrespective of whether or not the patients had active disease. The ACA were present infrequently in Sjögren's syndrome, systemic lupus erythematosus, rheumatoid arthritis, immune thrombocytopenic purpura, Graves' disease, immune haemolytic anaemia, and vitiligo. Sera from 107 patients with various other autoimmune diseases were negative for ACA.

Primary small-intestinal lymphomas in Taiwan: immunoproliferative small-intestinal disease and nonimmunoproliferative small-intestinal disease

PURPOSE

The clinicopathologic findings in 45 adult Chinese patients with primary small-intestinal lymphoma (PSIL) are described and compared with those in Western countries and in underdeveloped nations. The efficacy of combination chemotherapy is also assessed.

PATIENTS AND METHOD

Six patients had immunoproliferative small-intestinal disease (IPSID) indicated by the presence of alpha-heavy chain protein (alpha-CP) in body fluids or tumor tissues. Thirty-nine patients had non-IPSID, including one with postrenal transplant lymphoma. Thirty-three non-IPSID patients received a minimum of four cycles of combination chemotherapy with cyclophosphamide, doxorubicin, vincristine, and prednisolone (CHOP).

RESULTS

All IPSID patients presented with the clinical and laboratory features of severe intestinal malabsorption, and all had diffuse lymphoplasmacytic infiltration in the mucosa of the small bowel. Lymphomas were localized mainly in the jejunum and mesenteric nodes. The histologic subtypes were diffuse large cell in two, immunoblastic in three, and diffuse mixed in one. All patients responded poorly to chemotherapy, with a median survival duration of 10.5 months. The common presenting symptoms of the 39 non-IPSID patients included abdominal pain (90%), weight loss (31%), abdominal mass (26%), obstruction (26%), and perforation (23%). Diffuse large-cell and immunoblastic lymphomas constituted 82% of cases. Four patients had stage IE, 19 stage II 1E, and 16 stage 112E disease according to the Musshoff's criteria; 22 had bulky tumors and 19 had multiple tumors. The tumors were completely resected in 14 patients. Of 33 patients treated with combination chemotherapy, 73% achieved a complete remission. With a median follow-up duration of 90 months, there have been four relapses, with only one at the primary tumor site. The overall 5-year survival and disease-free survival rates for non-IPSID patients who were treated with chemotherapy were 59% and 54%, respectively.

CONCLUSION

Intensive chemotherapy produces long-term disease-free survival in locally advanced non-IPSID PSIL.