Characterization of acute promyelocytic leukemia cases with PML-RAR alpha break/fusion sites in PML exon 6: identification of a subgroup with decreased in vitro responsiveness to all-trans retinoic acid

Of 113 acute promyelocytic leukemia cases documented to have diagnostic PML-RAR alpha hybrid mRNA, 10 cases (8.8%) had fusion sites in PML gene exon 6 (V-forms) rather than in the two common hybrid mRNA configurations resulting from breaksites in either PML gene intron 6 (L-forms) or intron 3 (S-forms). In 4 V-form cases, a common break/fusion site was discovered at PML gene nucleotide (nt) 1685, abutting a 3' cryptic splice donor sequence. The fusion site was proximal to the common site in 1 case and more distal in 5 cases. The open reading frame encoding a PML-RAR alpha gene was consistently preserved, either by an in-frame fusion site or by the insertion of 3 to 127 unidentified nts. In 2 V-form cases, hybridization analysis of the reverse transcriptase-polymerase chain reaction products with a PML-RAR alpha juction probe was required for discrimination from L-form cases. Two V-form subgroups were defined by in vitro sensitivity to all-trans retinoic acid (tRA)-induced differentiation: 4 of 4 cases tested with fusion sites at or 5' to nt 1685 (subgroup E6S) had reduced sensitivity (EC50 > or = 10(-7) mol/L), whereas 4 of 4 cases with fusion sites at or 3' to nt 1709 (subgroup E6L) had high sensitivity (EC50 < 10(-8) mol/L) indistinguishable from that of L-form and S-form cases. These results provide the first link between PML-RAR alpha configuration and tRA sensitivity in vitro and support the importance of subclassifying APL cases according to PML-RAR alpha transcript type.

CD44 variant expression is a common feature of epithelial ovarian cancer: lack of association with standard prognostic factors

PURPOSE

CD44 is a hyaluronic acid receptor that exists as a standard 90-kd form (CD44S) as well as several CD44 variant isoforms produced through alternative splicing. Expression of CD44 variants is associated with clinically aggressive behavior in some human tumors. The purpose of the present study is to define the expression of CD44 variant isoforms in ovarian cancer and to investigate whether the expression of these molecules is associated with adverse prognosis.

MATERIALS AND METHODS

Six specimens of normal ovarian surface epithelium (NOSE) and 31 separate cases of newly diagnosed ovarian cancer were studied by a combination of reverse-transcription polymerase chain reaction (RT-PCR) and immunoperoxidase staining. Clinical correlation was made between CD44 variant expression and stage (I/II v III/IV), residual disease (< or = 2.0- v > 2.0-cm mass), age (< or = 65 v > 65 years), histology (papillary serous v other), grade, and survival.

RESULTS

RT-PCR analysis revealed that NOSE predominantly expressed transcripts for CD44S, as well as a restricted pattern of transcripts characteristic of CD44 splice variants. CD44S and CD44 variant exon nine sequences (CD44-9v) were focally expressed in one of two NOSE specimens examined by immunoperoxidase staining. In comparison, the majority (71%) of ovarian cancer specimens expressed a complex pattern of CD44 splice variants by RT-PCR analysis. Immunoperoxidase studies revealed that the majority of ovarian cancer specimens expressed both CD44S and CD44-9v, whereas expression of sequences from variant exons 3, 4, and 6 was uncommon. There was no association between CD44 variant expression (transcript or protein) and stage, residual disease, age, histology, grade, or survival.

CONCLUSION

Expression of CD44S and CD44-9v is a common feature of epithelial ovarian cancer cells. The lack of a significant association between CD44 variant expression and prognosis suggests that other factors may be more important in determining the clinical behavior of this disease.

High-dose ifosfamide, carboplatin, and etoposide pharmacokinetics: correlation of plasma drug levels with renal toxicity

An autologous bone marrow transplant regimen of ifosfamide, carboplatin, and etoposide (ICE) has been developed as treatment for certain malignancies. At maximum tolerated doses renal insufficiency precludes dose escalation. The objective was to examine whether measurement of plasma drug levels early during treatment would provide warning of renal failure. Nine patients received a 96-h continuous infusion of ifosfamide 16,000 mg/m2, carboplatin 1600 mg/m2, and etoposide 1200 mg/m2. Pharmacokinetics, including drug levels and plasma concentration-time curves, of ifosfamide, ultrafiltrable platinum (uPt) and etoposide were analyzed and correlated with renal function. One of the nine patients developed anuric renal failure requiring hemodialysis. By 17 h from the start of infusion, this patient showed substantially higher drug levels of ifosfamide (200 vs mean 217 microM) and uPt (19 vs mean 10 microM) than those patients with preserved renal function. The 95% confidence intervals suggested that a 16-22 h ifosfamide level > 153 microM and an uPt level > microM predict the development of significant renal dysfunction. Although drug levels were substantially higher at 56 h, the serum creatinine did not yet reflect kidney injury. This study suggests that high plasma ifosfamide and uPt levels, analyzed early in the course of a 96-h infusion of high-dose ICE, provide warning of severe and potentially fatal renal injury. Since ICE has substantial activity in a number of malignancies, but significant renal morbidity, real-time pharmacokinetic-guided dosing may reduce treatment-related toxicity.

Cell-to-cell communication in osteoblastic networks: cell line-dependent hormonal regulation of gap junction function

We have characterized the distribution, expression, and hormonal regulation of gap junctions in primary cultures of rat osteoblast-like cells (ROBs), and three osteosarcoma cell lines, ROS 17/2.8, UMR-106, and SAOS-2, and a continuous osteoblastic cell line, MC3T3-E1. All cell lines we examined were functionally coupled. ROS 17/2.8 were the more strongly coupled, while ROB and MC3T3-E1 were moderately coupled and UMR-106 and SAOS-2 were weakly coupled. Exposure to parathyroid hormone (PTH) for 1 h increased functional coupling in ROB cells in a concentration-dependent manner. Furthermore, PTH(3-34), an analog of PTH with binds to the PTH receptor and thus attenuates PTH-stimulated cAMP accumulation, also attenuated PTH-stimulated functional coupling in ROB. This suggests that PTH increases functional coupling partly through a cAMP-dependent mechanism. A 1 h exposure to PTH did not affect coupling in ROS 17/2.8, UMR-106, MC3T3-E1, or SAOS-2. To examine whether connexin43 (Cx43), a specific gap junction protein, is present in functionally coupled osteoblastic cells, we characterized Cx43 distribution and expression. Indirect immunofluorescence with antibodies to Cx43 revealed that ROS 17/2.8, ROB, and to a lesser extent MC3T3-E1 and UMR-106, expressed Cx43 immunoreactivity. SAOS-2 showed little if any Cx43 immunoreactivity. Cx43 mRNA and Cx43 protein were detected by Northern blot analysis and immunoblot analysis, respectively, in all cell lines examined, including SAOS-2. Our findings suggest that acute exposure to PTH regulates gap junction coupling, in a cell-line dependent manner, in osteoblastic cells.(ABSTRACT TRUNCATED AT 250 WORDS)

New semisynthetic pneumocandins with improved efficacies against Pneumocystis carinii in the rat

A new series of semisynthetic, water-soluble pneumocandin analogs has been found to be extremely potent against Pneumocystis carinii in an immunocompromised-rat model. These compounds are 5 to 10 times more potent than the parent natural product, pneumocandin B0 (L-688,786) (R. E. Schwartz et al., J. Antibiot. 45:1853-1866, 1992), and > 100 times more potent than cilofungin. One compound in particular, L-733,560, had a 90% effective dose against P. carinii cysts of 0.01 mg/kg of body weight when delivered parenterally (subcutaneously, twice daily for 4 days). This compound was also effective when given orally for the treatment and prevention of P. carinii pneumonia. For treating acute P. carinii pneumonia, oral doses of 2.2 mg/kg twice daily for 4 days were required to eliminate 90% of the cysts. A once-daily oral prophylactic dose of 2.2 mg/kg prevented cyst development, and a dose of 6.2 mg/kg prevented any development of P. carinii organisms (cysts and trophozoites), as determined through the use of a P. carinii-specific DNA probe (P. A. Liberator et al., J. Clin. Microbiol. 30:2968-2974, 1992). These results demonstrate that the antipneumocystis activities of the pneumocandins can be significantly improved through synthetic modification. Several of these compounds are also extremely effective against candidiasis (K. Bartizal et al., Antimicrob. Agents Chemother. 39:1070-1076, 1995) and aspergillosis (G. K. Abruzzo et al., Antimicrob. Agents Chemother. 39:860-894, 1995) in murine models, making them attractive as broad-spectrum antifungal agents.

Levels of soluble interleukin-2 receptors are predictive of response in patients treated with interleukin-2 and lymphokine-activated killer cells

Soluble interleukin-2 receptor (sIL-2R) alpha (CD25) levels were serially determined in the sera of 20 patients who had undergone adoptive immunotherapy with high-dose IL-2 and lymphokine-activated killer (LAK) cells for various types of metastatic solid tumors or Hodgkin's disease. The treatment course consisted of 5 days of high-dose IL-2 priming followed by the collection of peripheral blood leukocytes by leukapheresis, and in vitro activation of mononuclear cells with IL-2, and the subsequent infusion of such prepared LAK-cells together with IL-2. sIL-2R levels increased in all patients following IL-2 administration, and the ratio of baseline sIL-2R levels to those measured after 5 days of IL-2 was significantly correlated with pre-IL-2 levels (p = 0.016) in that higher pre-IL-2 levels resulted in a larger increase upon IL-2 administration. In terms of treatment outcome, the variables analysed included sIL-2R levels, total IL-2 doses administered, the expression of membrane-bound CD25 on in vitro cultured cells (pre- and post-IL-2 exposure), the total number of LAK-cells infused and in vitro cytotoxic activity of LAK-cells against the natural killer cell-resistant cell line Daudi. In a multivariate analysis, low baseline sIL-2R levels (p = 0.095) and high in vitro cytotoxic activity of LAK-cells against Daudi cells (p = 0.082) were jointly associated with response. Our data suggest that serum sIL-2R levels provide a fast and noninvasive parameter for predicting the response in patients treated with IL-2 and LAK-cells.

Leiomyoma primary cultures have elevated transcriptional response to estrogen compared with autologous myometrial cultures

OBJECTIVE

We tested the hypothesis that uterine leiomyomas are hypersensitive to estrogen as compared with autologous human myometrium.

METHODS

The estrogen-induced transcriptional responses of uterine leiomyoma and myometrial primary cultures were determined by transient expression assays. The relative levels of estrogen receptor (ER) in myometrial and leiomyoma tissues were determined by immunoblot.

RESULTS

Myometrial and leiomyoma primary cultures were transcriptionally responsive to the estrogen ethinyl estradiol (eE2). The partial agonist tamoxifen did not elicit a positive transcriptional response and antagonized estrogen-induced transcription in the cultured cells. The responses of hormone-treated leiomyoma cells averaged 4.5-fold higher than those in controls with no hormone (P = .0001). The myometrial cells from women in the follicular phase exhibited little if any transcriptional response to eE2, whereas myometrial cells from women in the luteal phase had a transcriptional response to eE2 averaging threefold higher than that in no-hormone controls (P = .0083). Differences in response between autologous myometrial and leiomyoma cultures were statistically significant by the two-tailed Wilcoxon paired nonparametric signed-rank test (n = 11; P = .0137). These differences were more pronounced in cultures from women in the follicular or early luteal phase. In addition, the levels of ER increased in follicular and early luteal phase myometrial tissues, which correlated well with the number of days from the last menstrual period (n = 8; r = 0.9046; P = .002). Estrogen-receptor levels in myometrial tissues decreased during the late luteal phase. Levels in leiomyoma tissues did not follow the same pattern as in the myometrium and were elevated in tissues taken from women in the follicular phase.

CONCLUSIONS

Autologous leiomyoma cultures have a significantly higher response to estrogen than do matched myometrial cultures, especially if the cultures are derived from the follicular phase. The levels of ER in leiomyoma tissue from women in the follicular phase are significantly elevated.

The phosphorylated ribosomal protein S7 in Tetrahymena is homologous with mammalian S4 and the phosphorylated residues are located in the C-terminal region. Structural characterization of proteins separated by two-dimensional polyacrylamide gel electrophoresis

A single basic ribosomal protein, protein S7, can be multiply phosphorylated in the ciliated protozoan Tetrahymena. Induction of phosphorylation is highly regulated, and the phosphorylation proceeds in a strictly sequential manner. The first site to be phosphorylated is a serine residue and the second a threonine. In this paper we report the complete primary structure of Tetrahymena thermophila ribosomal protein S7 including identification of the phosphorylated serine and threonine residues. Most of the sequence information was obtained from peptides generated by in situ digestion of S7 in two-dimensional gels using an approach that combined traditional protein chemistry with mass spectrometry. T. thermophila ribosomal protein S7 has a molecular mass of 29,459 Da and contains 259 amino acid residues. Phosphorylation takes place on Ser258 and Thr248 in the C-terminal region of the protein. Alignment of T. thermophila ribosomal protein S7 with known ribosomal proteins yielded the surprising result that T. thermophila S7 is homologous, not with mammalian ribosomal protein S6, but with mammalian ribosomal protein S4. These findings clearly distinguish the pattern of phosphorylation of ribosomal proteins in Tetrahymena from all other eukaryotes analyzed to date.

Monoclonal antibody-purged bone marrow transplantation therapy for multiple myeloma

This report describes the clinical characteristics, treatment associated toxicity, and follow-up of fifty-eight patients with plasma cell--dyscrasias treated with high dose chemotherapy and total body irradiation (TBI) at a single institution. Following TBI, 36 patients received anti-B cell monoclonal antibody (MoAb)-treated autologous bone marrow, 21 patients received anti-CD6 cell MoAb-treated allogeneic bone marrow to deplete T cells, and one patient received unpurged bone marrow from a syngeneic donor. Evaluation after high dose chemotherapy and bone marrow transplantation (BMT) demonstrated 26 complete responses (CR), 26 partial responses (PR), 2 non-responders, 1 not yet evaluated, and three toxic deaths. Fourteen of 36 patients who underwent autologous BMT are alive free from progression at 18 (range 5 to 68) months post transplant (post-BMT); of these, 11 remain in continuous complete response at 16 (range 5 to 68) months post-BMT. Seven of 21 patients who underwent allogeneic BMT are alive free from progression at 30 (range 4 to 44) months post-BMT; of these, three patients remain in continuous complete response at 43 (range 33 to 45) months post-BMT. These data suggest that high dose chemotherapy with TBI followed by MoAb purged BM can be performed with acceptable toxicity and high tumor response rates.

[Characteristics of isoforms of Serratia marcescens from electrospray mass spectrometry]

Electrospray mass spectrometry was used to determine the molecular masses of nuclease isoforms isolated and purified from the cultural fluid of Serratia marcescens B10M1. The primary structure of each of the isoforms isolated from the nuclease preparations was established by comparing their masses with the known amino acid sequence encoded by the nuc-gene. The structure of some of these isoforms was verified by N-terminal sequencing, that of nearly all isoforms-by isoelectric focusing. All nuclease isoforms were found to be variants of native nuclease split at the molecular N-termini.

Rearrangement of chromosomal bands-3p13-14 in 2 hamartomas of the breast

Cytogenetic aberrations have until now not been reported in mammary hamartomas. The finding of multiple, karyotypically abnormal clones in short-term cultures from 2 such tumors supports the interpretation that these are genuinely neoplastic lesions. The deletion del (3) (p13p14) and trisomy 18, both known to occur as primary chromosome abnormalities in breast carcinoma, were among the clonal changes in one case each. Since both tumors had structural abnormalities of 3p13-14, admittedly leading to different derivative chromosomes, rearrangement of this region might represent a unifying feature in the genesis of mammary hamartomas.

A comparison of peripheral blood stem cell apheresis using the Fenwal CS3000 Plus and COBE Spectra

We have compared the leukapheresis products collected on the Fenwal CS3000 Plus and COBE Spectra in a well-controlled patient population. While statistically significant differences were found, i.e. in product hematocrit, volume, number of granulocytes and platelets collected, these are not felt to be physiologically important. Similar efficiency in collecting mononuclear cells and colony forming unit assay results indicate that each instrument is capable of harvesting hematopoietic progenitor cells from peripheral blood.

Modulation of multidrug resistance in de novo adult acute myeloid leukemia: variable efficacy of reverting agents in vitro. Eastern Cooperative Oncology Group

The efficacy of verapamil and cyclosporine A as modulators of P-glycoprotein, the multidrug resistance (MDR1) gene product, was studied in leukemic blast cells from 56 patients with de novo acute myeloid leukemia (AML) in vitro. Rhodamine123 dye-efflux was measured flow cytometrically as a cellular parameter reflecting P-glycoprotein activity. While dye-efflux was measurable in 3/4 of the cases, the capacity of the P-glycoprotein inhibitors varied substantially among patients. In 23 patients, P-glycoprotein function was completely inhibited by the resistance modulators, whereas in 17 patients neither verapamil nor cyclosporine had any reverting effect on dye-efflux at concentrations even 10-times higher than achievable in vivo. Cells with a drug-sensitive rhodamine123-pump effluxed more efficiently (p = 0.0016) and contained significantly higher levels of MDR1 specific RNA transcripts (p = 0.0002), as determined by quantitative PCR, than cells exhibiting an efflux process that could not be inhibited. However, flow cytometric evaluation of the staining of gated blast cells with the anti-P-glycoprotein antibody, 4E3.16, revealed no difference in P-glycoprotein expression between modulator-sensitive and -insensitive cases (p = 0.86), indicating disproportionate translation of MDR1 mRNA. In leukemic cell populations with increased P-glycoprotein function that could be inhibited, significantly more blasts expressed the progenitor cell antigen, CD34 (median 83%), than was the case in leukemias with P-glycoprotein activity that could not be inhibited (median 7%) (p = 0.0001). The present study demonstrates that a substantial fraction of AML patients constitutively display a drug-efflux mechanism suggestive of P-glycoprotein activity.(ABSTRACT TRUNCATED AT 250 WORDS)

Thyroid function and autoimmunity in pernicious anemia before and during cyanocobalamin treatment

Out of 35 consecutive patients with decreased plasma-cobalamin 22 had newly diagnosed overt pernicious anemia (PA) six of which had a known history of thyroid disease. At referral, 5 of these 6 were thyroid peroxidase antibody (TPOAb)-positive and 2 were thyroglobulin antibody (TgAb)-positive, while none were thyroid stimulating antibody (TSAb)-positive (an overall autoantibody appearance of 83.3%). Fifty percent of the 22 patients had TPOAb and 13.6% had TgAb compared to 18.2% and 4.5%, respectively in sex and age matched healthy controls. Six PA-patients without a history of thyroid disease had thyroid autoantibodies and another patient seroconverted within the first year during treatment with cyanocobalamin. Measurements of serum concentrations of thyroid hormones and thyroid stimulating hormone were performed during the first year of treatment with cyanocobalamin. Two cases of subclinical myxoedema were found among PA-patients and another case was found among patients with latent PA. The female:male ratio of thyroid disease among PA-patients and among thyroid autoantibody-positive PA-patients was interestingly found to be 1:1. Treatment with cyanocobalamin did not have any systematic effect on thyroid function. Routine screening for thyroid function and thyroid autoantibodies in patients with latent or overt PA is recommended.

Advanced diffuse non-Hodgkin's lymphoma. Analysis of prognostic factors by the international index and by lactic dehydrogenase in an intergroup study

BACKGROUND

Recent data have suggested that there are no differences among various anthracycline-based chemotherapy regimens [including cyclophosphamide, vincristine, methotrexate, and prednisone (CHOP), methotrexate, calcium leucovorin, bleomycin, doxorubicin, cyclophosphamide, and dexamethasone (m-BACOD), methotrexate, doxorubicin, cyclophosphamide, vincristine, prednisone, and bleomycin (MACOP-B), and cyclophosphamide, doxorubicin, etoposide, prednisone, cytosine arabinoside, bleomycin, vincristine, methotrexate, and calcium leucovorin (PROMACE-cyta-BOM)] in patients with diffuse aggressive lymphomas. Because outcome appears to depend on certain prognostic factors, risk groups can be identified. Therefore, these prognostic factors were examined for their correlations with survival, time-to-treatment failure (TTF), and disease free survival (DFS) in a group of patients with diffuse aggressive non-Hodgkin's lymphoma who were treated on a single randomized trial with either CHOP or m-BACOD.

METHODS

From July 1984 to January 1988, 392 patients with diffuse large cell or diffuse mixed non-Hodgkin's lymphoma were enrolled in an Intergroup study and were randomly assigned to treatment with CHOP or m-BACOD chemotherapy. Of these, 325 were eligible for response, toxicity, and survival analysis, and the results were reported. The survival and TTF results now have been updated. The 286 patients who had lactic dehydrogenase (LDH) data available at study entry were analyzed for prognostic features according to the International Index criteria and using Martingale Residuals for proportional hazards regression.

RESULTS

There were no differences in survival, TTF, and disease free survival between groups of patients treated with either CHOP or m-BACOD. In addition, analysis using the International Index criteria confirmed that patients in the lower risk groups had better outcome than patients in the higher risk groups (5-year survival was 56 and 58% for low and low/intermediate risk groups, respectively, and 37% and 31% for high/intermediate and high risk groups, respectively). There were, however, no differences in survival, disease free survival, or TTF within any risk group when treatment with CHOP or m-BACOD were compared. In addition, analysis using Martingale residuals for proportional hazards regression identified LDH level (> 3 x normal) as an important prognostic factor that was not captured by the International Index. Thus, 5-year survival was 57% if LDH was normal or below, 42% if LDH was 1-3 x normal, and 21% if LDH was > 3 x normal.

CONCLUSION

In patients with advanced diffuse large cell or diffuse mixed non-Hodgkin's lymphoma, there are no differences in outcome that can be attributed to treatment with CHOP vs. m-BACOD; this holds for any prognostic group identified by the International Index. However, the level of LDH at time of study entry is an important prognostic factor that is predictive of survival and may help to identify candidates for future clinical trials.

Serum immunoglobulin G subclasses in patients with ulcerative colitis and Crohn's disease of different disease activities

BACKGROUND

Different concentrations of immunoglobulin G (IgG) subclass-producing cells in the mucosa of patients with ulcerative colitis and Crohn's disease have previously been described.

METHODS

To evaluate serum concentration of IgG subclasses as a tool for diagnosis and disease activity in chronic inflammatory bowel disease, we compared serum concentrations of IgG, IgA, IgM, and immunoglobulin subclasses IgG1, IgG2, IgG3, and IgG4 by means of the radial immunodiffusion technique in 66 patients with ulcerative colitis and in 68 patients with Crohn's disease of different clinical stages. Erythrocyte sedimentation rate, haemoglobin, and serum concentrations of albumin and orosomucoid were also determined.

RESULTS

The serum IgG1 concentration in patients with ulcerative colitis was 8.0 g/l significantly higher than in patients with Crohn's disease (6.8 g/l) (p < 0.005), whereas the serum IgG2 concentration in patients with Crohn's disease was 3.8 g/l, significantly increased compared with patients with ulcerative colitis (3.1 g/l) (p < 0.004). In patients with active ulcerative colitis the serum IgA level (2.03 g/l) was significantly lower than that in the patients with less active disease (2.74 g/l) (p < 0.03). No significant differences in serum concentrations of total IgG, IgG3, IgG4, and IgM were found between groups of patients with ulcerative colitis and Crohn's disease. The differences observed in IgG1, IgG2, and IgA concentrations, however, are small.

CONCLUSIONS

The serum concentrations of IgG, IgA, IgM, and IgG subclasses are of little value in the diagnostic procedures in individual patients and are not superior to conventional laboratory tests such as sedimentation rate and serum concentrations of orosomucoid and albumin.

Long-term follow-up of a CHOP-based regimen with maintenance therapy and central nervous system prophylaxis in lymphoblastic non-Hodgkin's lymphoma

The Eastern Cooperative Oncology Group (ECOG) conducted a phase II trial in adult patients with lymphoblastic non-Hodgkin's lymphoma. Thirty-nine patients with no central nervous system (CNS) involvement were treated with an induction cyclophosphamide, doxorubicin, vincristine, and prednisone (CHOP)/L-asparaginase regimen and CNS prophylaxis that included intrathecally administered methotrexate given 6 times and 24 Gy midplane cranial radiation in 12 fractions. Thirty-one patients (79%) achieved a complete remission (CR). Of the 31 patients with CRs, 12 relapsed (39%). CNS relapse occurred in three patients. All patients who entered a CR were treated with maintenance CHOP, cytosine arabinoside (AraC), and methotrexate and subsequently with Ara-C and methotrexate. Life-threatening leukopenia or thrombocytopenia was experienced in 69% of patients in the induction phase and in 70% in the maintenance phase. Nineteen of 39 patients (49%) remain in CR with a followup to 9 years. Bone marrow involvement was associated with a significantly worse survival (P = 0.03).

Mycobacterium paratuberculosis in intestinal tissue from patients with Crohn's disease demonstrated by a nested primer polymerase chain reaction

BACKGROUND

The etiology of Crohn's disease remains unknown, but current research has concentrated on autoimmunity and/or mycobacterial infection. The polymerase chain reaction (PCR) enables the detection of genetic material even when very few microorganisms are present.

METHODS

A nested primer PCR for detection of a multi-copy insertional element (IS900) specific for Mycobacterium paratuberculosis was applied to DNA extracted from fresh and from paraffin-embedded intestinal tissue obtained from patients undergoing surgery.

RESULTS

In fresh intestinal tissue from 11 of 24 patients with Crohn's disease, from 2 of 10 patients with ulcerative colitis, and from 3 of 28 patients with other colonic disorders, specific M. paratuberculosis DNA was found. In paraffin-embedded Crohn's disease tissue the presence of specific M. paratuberculosis DNA was also increased.

CONCLUSIONS

Whether the presence of M. paratuberculosis is connected to the inflammatory bowel disease or is a mere coincidence cannot be stated. We find this presence interesting and encouraging for further investigations.

Therapy with recombinant human erythropoietin in patients with myelodysplastic syndromes

We conducted a Phase I-II trial of recombinant human erythropoietin-beta (rhEPO) in patients with myelodysplastic syndrome (MDS). Patients with anemia and pathologically confirmed MDS were eligible for the study. Treatment consisted of rhEPO by subcutaneous injection thrice weekly for 6 weeks at one of three dose levels (100 U/kg (three patients), 200 U/kg (three patients) and 400 U/kg (14 patients)). Ferrous sulfate (325 mg po tid) was also administered if the transferrin saturation was below 30% (two patients). Patients were monitored with weekly CBC, white cell differential, and reticulocyte counts. Bone marrow examinations were performed at the conclusion of the treatment period and after a 2 week washout period. Patients who responded to therapy were continued on rhEPO at the same dose for 6 additional months. Response criteria included: 50% reduction in transfusion requirements compared with the 6 week pre-study period; doubling of reticulocyte count that was maintained on two determinations at least 1 week apart; or an increase in hemoglobin by at least 1.2 gm/dl without transfusions. Pre-treatment factors potentially predictive of response were analyzed by univariate analysis and in a multivariate fashion by classification and regression trees. Seven of the twenty patients sustained an untransfused rise in serum hemoglobin > or = 1.2 gm/dl. Four of the sixteen patients (including three of seven patients experiencing a rise in serum hemoglobin) who were transfusion-dependent prior to the study achieved a reduction or elimination of their transfusion requirements. Five of thirteen patients who received rhEPO during the extension phase had a continued response. A low baseline erythropoietin level (< 50 mU/ml) was the best predictor of hemoglobin response when controlling for other variables. rhEPO has a role in the treatment of certain patients with MDS, particularly in those whose endogenous serum erythropoietin levels are not markedly elevated.

The immunophenotype of acute promyelocytic leukemia (APL): an ECOG study

In 452 adult patients with de novo acute myeloid leukemia (AML), a series of 22 monoclonal antibodies was used to identify immunophenotypic characteristics of acute promyelocytic leukemia (APL) as compared to other AMLs (groups FAB M1/M2 and M4/M5). Only those patients with FAB M3 cytology were included in the analysis for which APL was confirmed by the presence of the t(15;17) cytogenetic aberration and the detection of the PML/RAR alpha gene fusion transcript by PCR amplification (35 cases). Significantly fewer APL blast cells were positive for the stem cell antigen, CD34 (p = 0.0001) as well as for HLA-DR (p < 0.0001). With respect to myeloid antigens, APLs less frequently expressed the myelomonocytic antigens, CD11b (p = 0.0001) and CD14 (p = 0.0013), whereas expression of CD33, a pan-myeloid marker, was more frequent in APL (p = 0.0001). CD15, the X-hapten carbohydrate structure (lacto-N-fucopentaose-III), typically expressed at the maturation stage of normal promyelocytes, was found to be sialylated on APL blasts as recognized by differential binding of the anti-CD15 antibodies, VIM-D5 (non-sialylated CD15) and VEP-9 (sialylated CD15). Expression of the T-cell associated CD7 antigen was rarer on APL than non-APL cells (p = 0.0001), as was that of the multidrug resistance P-glycoprotein (p = 0.0038). Marginal correlations existed between antigen profile (particularly CD2) and the type of PML/RAR alpha transcripts. In addition to its unique genotypic features, these data establish APL as a distinct immunophenotypic entity.

Significantly lower P-glycoprotein expression in acute promyelocytic leukemia than in other types of acute myeloid leukemia: immunological, molecular and functional analyses

Expression of P-glycoprotein (Pgp), the product of the multidrug resistance (MDR1) gene, detected by flow cytometric analysis of the binding of antibody 4E3.16, was found on significantly fewer leukemic cells in 35 adult patients with de novo acute promyelocytic leukemia (APL) (mean 14.8%, median 7%) than in 184 patients with non-APL acute myeloid leukemia (AML) at diagnosis (mean 28.3%, median 18%) (p = 0.0038). APL was diagnosed based on morphology, the detection of t(15;17) and of the chimeric fusion transcript PML/RAR alpha by PCR. To further substantiate low MDR1 expression in APL, we studied cells from 11 APL patients at the molecular and functional level in comparison to 48 non-APL cases. The diagnosis of APL was associated with the absence of Pgp function by the rhodamine efflux assay (p = 0.0001). Furthermore, MDR1-specific transcript levels, determined by quantitative PCR with two distinct sets of primers, were significantly lower in mononuclear cells from the APL than the other AML cases (p = 0.013). The frequency of leukemic cells positive for CD34, an antigen presumably associated with Pgp expression in AML, was significantly lower in APL than other AMLs (p = 0.0001). In contrast to non-APL leukemias, those few cases of CD34 strongly positive APL neither expressed Pgp nor contained significant MDR1 transcript levels. Low expression of Pgp by APL cells may provide the biologic basis for the high sensitivity of this leukemia subtype to chemotherapeutic agents in vivo.

Use of distal splenorenal shunt in children referred for liver transplant evaluation

Variceal bleeding remains a common cause of morbidity for children with both intrahepatic and extrahepatic portal hypertension. Occasionally, patients referred for liver transplant evaluation have significant variceal bleeding, despite adequate synthetic liver function. During a 7-year period, 322 children were referred for liver transplant evaluation. Six underwent distal splenorenal shunt surgery after evaluation. There were four boys and two girls. The average age was 11 +/- 4 years, and the average weight was 39 +/- 15 kg. The etiology of variceal bleeding was intrahepatic portal hypertension in five (1 biliary atresia, 2 chronic hepatitis, 2 congenital hepatic fibrosis) and extrahepatic portal vein thrombosis in one. Two patients had no previous attempts at sclerotherapy (one because of an abnormality in platelet function, the other because of extensive gastric varices), and four had multiple previous sclerotherapy treatments. No patient had preoperative encephalopathy. Three cases were Child's class A, and three were Child's class B. Preoperative evaluation of the portasystemic system was performed with magnetic resonance (MR) imaging or splenoportography. All patients underwent a distal splenorenal shunt procedure, four of whom also had splenopancreatic disconnection. One patient required 100 mL of blood replacement, and five required no blood. The average length of hospital stay was 9.8 +/- 2.2 days. Postoperative complications were minimal. All patients are alive, without recurrent gastrointestinal bleeding or encephalopathy, and they have patent shunts, which was confirmed by MR or Doppler ultrasound at a mean of 25 +/- 20 months after shunt surgery.(ABSTRACT TRUNCATED AT 250 WORDS)

[AIDS with apoplectic onset]

Four cases with an apoplectic debut of AIDS are reported. Two of the patients had not earlier been identified as being HIV-positive. In three patients, the underlying cause was probably cerebral toxoplasmosis. It is important to consider AIDS in the differential diagnosis of stroke, particularly in young adults.