Application of peripherally inserted central catheter in acute myeloid leukaemia patients undergoing induction chemotherapy.

Increasingly, peripherally inserted central catheters (PICC) are applied in patients with haematological malignancies. The feasibility and safety of PICC for induction chemotherapy in acute myeloid leukaemia (AML) remain unclear. Medical records of 89 newly diagnosed adult de novo AML patients, who achieved complete remission, were retrospectively reviewed (PICC group, n = 43; intravenous [IV] line group, n = 46). Patients' clinical characteristics and the number of blind punctures for blood sampling were compared between these two groups, and risk factors associated with bacteraemia were identified by univariate analysis. Patients in the PICC group experienced significantly fewer blind punctures than those in the IV line group (3.3 ± 3.6 vs. 14.4 ± 6.0; p = .000); 20.9% of PICC patients had bacteraemia, compared with 23.9% in the IV line group (p = .803). Most patients (76.7%) removed their PICC because treatment was completed. PICC increased the quality of life in AML patients undergoing chemotherapy induction by reducing the number of blind blood punctures required. Bacteraemia in PICC patients was comparable to that in IV line patients. PICC is, therefore, a feasible and safe central venous device for use in AML patients.

Malignancy-associated chylothorax: a 20-year study of 18 patients from a single institution.

Malignancy-associated chylothorax is a rare manifestation with uncertain characteristics and clinical significance. We segregated 18 patients into malignant lymphoma (n= 11) and solid malignancy (n= 7) groups to analyse the characteristics, treatment response and prognostic value of malignancy-associated chylothorax. Diagnosis of chylothorax was confirmed by a triglyceride concentration of >110 mg/dL or by the presence of chylomicrons in the pleural effusion. Concentrations of glucose, protein and lactate dehydrogenase did not differ significantly between the malignant lymphoma and solid malignancy groups. Although not statistically significant (P= 0.25), 90.9% malignant lymphoma patients and 57.1% solid malignancy patients had exudates. The cytology diagnostic rate in the malignant lymphoma and solid malignancy groups was 20.0% and 33.3% respectively (P > 0.99). After chemotherapy, six malignant lymphoma patients achieved complete remission, with simultaneous chylothorax disappearance. The overall survival rate at 12 and 24 months in the malignant lymphoma group was 54.5% and 36.4% respectively, while that in the solid malignancy group was 35.7% and 0% respectively. Malignant lymphoma was the chief cause of chylothorax in our cohort. Effective lymphoma treatment, lacking supplementary interventions, is essential for treating chylothorax in malignant lymphoma patients. Chylothorax indicates extremely limited life expectancy for solid malignancy patients.

Syngeneic peripheral blood stem cell transplantation with brief immunosuppression for severe aplastic anemia.

We report the cases of two severe aplastic anemia (SAA) patients who were successfully treated with syngeneic peripheral blood stem cell transplantation (PBSCT) using immunosuppression without high-dose chemotherapy or irradiation for conditioning. A 21-year-old woman with SAA of 6 years duration had been transfused heavily before transplantation and had developed refractory thrombocytopenia, chronic hepatitis and secondary hematochromatosis. Syngeneic PBSCT with immunosuppression using ATG, methylprednisolone, and cyclosporin-A was eventually performed without high-dose chemotherapy in September 1997. The second syngeneic PBSCT with the same immunosuppression was successfully performed in a 35-year-old male patient who had had SAA for 3 months in November 1998. Haemopoietic engraftment was rapid and sustained. There was no infection or mucositis during the syngeneic PBSCT. The patients are currently 9 to 22 months post-PBSCT without rejection. Our experience suggests that syngeneic PBSCT with brief immunosuppression is an effective alternative to pretransplant high-dose chemotherapy conditioning for SAA patients having syngeneic transplantation. Bone Marrow Transplantation (2000) 25, 337-339.

Estimation of 2-D noisy fractional Brownian motion and its applications using wavelets.

The two-dimensional (2-D) fractional Brownian motion (fBm) model is useful in describing natural scenes and textures. Most fractal estimation algorithms for 2-D isotropic fBm images are simple extensions of the one-dimensional (1-D) fBm estimation method. This method does not perform well when the image size is small (say, 32x32). We propose a new algorithm that estimates the fractal parameter from the decay of the variance of the wavelet coefficients across scales. Our method places no restriction on the wavelets. Also, it provides a robust parameter estimation for small noisy fractal images. For image denoising, a Wiener filter is constructed by our algorithm using the estimated parameters and is then applied to the noisy wavelet coefficients at each scale. We show that the averaged power spectrum of the denoised image is isotropic and is a nearly 1/f process. The performance of our algorithm is shown by numerical simulation for both the fractal parameter and the image estimation. Applications to coastline detection and texture segmentation in a noisy environment are also demonstrated.

Autologous peripheral blood stem cell transplantation using simplified procedures for collection and freezing.

BACKGROUND: High-dose therapy with peripheral blood stem cell (PBSC) transplantation has been used increasingly for chemosensitive malignancies. The conventional procedures for collection and freezing of PBSCs are time-consuming and expensive. The optimal conditions for priming, collection and freezing of PBSCs have yet to be simplified. METHODS: Simplified procedures for mobilization, collection and freezing were developed to provide PBSC transplantation. Twenty-two cancer patients were given intensive chemotherapy with a variety of regimens using granulocyte-colony stimulating factor (G-CSF, filgrastim) 300 micrograms/d subcutaneously to mobilize PBSCs. A rapidly rebounding white blood cell (WBC) count from nadir was used to predict the time of peak PBSC release and plan leukapheresis. Leukapheresis was performed, when the WBC count was greater than 1.0 x 10(9)/l. RESULTS: Leukapheresis was performed in all 22 patients on day 10 to 14 after completing intensive chemotherapy. G-CSF to mobilize PBSCs was administered for a median of 10 days (range, 7-12 days). Twenty-one of 22 patients achieved the target yield of greater than 2 x 10(6) CD34+ cells/kg of body weight (BW). This was achieved in a median of two harvests (range, 2-4), with a median processed blood volume of 10.2 l/apheresis. A median of 6.4 x 10(8) mononuclear cells/kg BW and 5.2 x 10(6) CD34+ cells/kg BW for each patient were obtained. After high-dose cancer chemotherapy and PBSC transplantation, rapid and sustained hematopoietic engraftment occurred in all but one patient who had an inadequate number of CD34+ cells. In patients with an adequate target yield of CD34+ cells, the median times to achieve an absolute neutrophil count of greater than 0.5 x 10(9)/l and a platelet count of greater than 20 x 10(9)/l were nine days (range, 7-12 days) and 12 days (range, 8-14 days), respectively. CONCLUSIONS: Adequate PBSCs can be achieved within a median of two aphereses in most eligible cancer patients. Apheresis should be performed on day 10 to 14 after completing intensive chemotherapy, followed by G-CSF 300 micrograms/d. This simple and effective approach makes PBSC transplantation more practicable for a wider range of malignant diseases.

The encapsidation signal of hepatitis B virus facilitates preC AUG recognition resulting in inefficient translation of the downstream genes.

Hepatitis B virus (HBV) DNA polymerase (P) is translated from a bicistronic pregenomic RNA via a ribosomal leaky scanning mechanism. Another viral transcript, the preC RNA, differs from pregenomic RNA by the presence of some 30 nt at the 5' end that encompass the preC initiation codon. This RNA is used exclusively for expression of the precore protein which is a precursor of secreted HBeAg. Factors leading to inefficient translation of the P and C proteins from the preC RNA were explored using a genetic approach in transient transfection assays. Our data indicate that when translating the precore protein, the elongation arrest that occurs during targeting of nascent polypeptide chains to the endoplasmic reticulum interferes with the scanning of the 40S ribosomal subunits. Such interference seems to hinder initiation of the ribosomes at the downstream genes. Furthermore, the presence of the preC initiator codon in the preC mRNA has resulted in a reduction in the number of scanning ribosomes reaching the C and P initiator codons compared with the case of pregenomic RNA. Finally, although the preC initiator codon is in a suboptimal context for translation initiation, an RNA secondary structure, the encapsidation signal, located downstream to the initiator codon is shown to enhance codon recognition, resulting in a depletion of the number of 40S ribosomal subunits available for scanning of the downstream AUG codons. This study demonstrates that the HBV encapsidation signal plays an additional role in facilitating recognition of the preC initiator codon.

Translational regulation of hepatitis B virus polymerase gene by termination-reinitiation of an upstream minicistron in a length-dependent manner.

Hepatitis B virus (HBV) polymerase (P) gene is translated from the bicistronic pregenomic RNA with the core (C) gene in the first cistron. The P ORF is preceded by the C AUG and three AUG codons within the C region, where a minicistron of 7 amino acids can potentially be translated. Our results indicate that the efficiency of the P gene translation initiation was about 10% of that of the C gene when both genes were fused in-frame to a lacZ reporter in an mRNA similar in structure to the pregenomic RNA. By mutational analysis, about 74% of the translation initiation of HBV P gene was shown to be by ribosomes that reinitiated after terminating translation of this minicistron, while the rest was by two mechanisms: one by ribosomes leaky scanning through every upstream AUG and the other by ribosomal backwards scanning to the P AUG after finishing the translation of the C gene. The efficiency of termination-reinitiation depended on the size of the minicistron, i.e. the reinitiation efficiency decreased about 50% when the size increased from 24 nt to 57 nt. When a 44 nt HBV sequence comprising the minicistron was inserted at the 5' untranslated region of the cat gene, CAT expression was regulated in a similar way to that of the HBV P gene. Moreover, when transfection occurred with an HBV expression plasmid containing an inactivated minicistron, production of virus-like particles dropped to about one-third of the wild-type level, suggesting that the termination-reinitiation mechanism is indeed important for HBV P gene expression.

Characterization of hepatitis B virus integrant that results in chromosomal rearrangement.

A hepatitis B virus (HBV) integrant was cloned from the genomic DNA library of human hepatocellular carcinoma cell line, Hep3B. Sequence analysis of the restriction fragment bearing the virus-host junction revealed that its integration pattern was the common type, with the right junction located at the cohesive region. The open reading frame of the major viral surface antigen was intact with rearranged preS1 and core sequences. The X protein, although truncated, maintained the trans-activating activity to simian virus 40 enhancer/promoter. S1 nuclease mapping showed that 4.0-, 2.9-, and 2.2-kb HBV RNAs detected in Hep3B cells were transcribed from this integrant using preS2/S promoter. By somatic-cell hybrid mapping, the left and right cellular flanking sequences were assigned to chromosomes 13 and 4, respectively. The results of this study support the notion that integrated hepatitis B virus, resulting in chromosomal rearrangement as well as the production of the carboxy-terminal truncated X protein with trans-activating activity, is important for viral hepatocarcinogenesis.

Shape from texture: estimation of planar surface orientation through the ridge surfaces of continuous wavelet transform.

In this correspondence, a method is proposed for estimating the surface orientation of a planar texture under perspective projection based on the ridge of a two-dimensional (2-D) continuous wavelet transform (CWT). We show that an analytical solution of the surface orientation can be derived from the scales of the ridge surface. A comparative study with an existing method is given.

Cloning and expression of an antigenic domain of glycoprotein gE of pseudorabies virus in Escherichia coli and its use as antigen in diagnostic assays.

Use of a combination of an effective gE gene-deleted pseudorabies virus (PRV) vaccine with a companion diagnostic kit for PRV glycoprotein gE has proven successful in several pseudorabies-eradication programs. To produce a large quantity of functional gE protein for development of a PRV-gE diagnostic kit, an Escherichia coli expression system containing the distal region of the PRV-gE gene of a PRV strain CF was constructed. The expressed protein contained 134 amino acids of gE protein (amino acids 77-210) fused to a 19-amino acids tag containing 6 histidine residues. After induction, a truncated PRV-gE polypeptide of 18-kd was expressed to about 20% of the total E coli proteins. Results of immunoblot analysis indicated that this E coli-produced PRV-gE protein reacted specifically with serum from PRV-hyperimmunized pigs and from field PRV-infected pigs, but not with serum samples from specific-pathogen-free pigs or pigs inoculated with gE-deleted PRV vaccine. These data indicate that, although the recombinant gE protein is produced in E coli, it still retains the antigenicity of the viral gE glycoprotein. Comparison between the recombinant gE protein, using immunoblot analysis with a commercial gE ELISA containing natural PRV-gE protein, revealed comparable test performance. This finding indicated that recombinant gE protein produced by E coli can be used for development of a companion serologic assay for a PRV-gE gene-deleted vaccine.

Demonstration of the presence of protease-cutting site in the spacer of hepatitis B viral Pol protein.

Molecular genetic studies have revealed that the human hepatitis B viral (HBV) Pol protein, a polypeptide of about 94 kDa, contains four domains. These are the 5'-terminal protein, spacer, RNA reverse transcriptase/DNA polymerase, and RNase H, respectively, from the amino (N) to carboxy (C) terminus. No evidence indicates as yet the involvement of a specific protease in cleaving the Pol protein or the presence of protease-cutting sites in the Pol protein. An in vitro-translated Pol protein was shown to be cleaved by purified thrombin but not in the presence of its inhibitor, hirudin. Two thrombin-cutting sites, spanning 194 amino acids, were then deduced by thrombin digestion of Pol protein with various lengths of C-terminal deletion. These two putative cutting sites, one located in the spacer region and the other in the beginning of the polymerase region, were found to be conserved at similar positions in the Pol protein of all hepadnaviruses. By using a novel method called the LacZ localization assay (LLA), it was demonstrated that a tripartite fusion protein containing the nucleus localization sequence (NLS) of SV40 large T Ag, the putative thrombin cutting sequence (Ile-Arg-Ile-Pro-Arg320-Thr) of HBV Pol protein and the full length beta-galactosidase of E. coli, exhibited a lower percentage (approximately 53%) of targeting into the nucleus of transfected hepatoma cells when compared with a similar tripartite protein containing a single mutation (Arg320 residue into Trp320) of HBV Pol protein (approximately 78%) or with a bipartite protein of SV40 NLS-beta-galactosidase (approximately 90%). These results indicate that the putative thrombin-cutting site in the spacer region of HBV Pol protein could be cleaved by a cellular protease resulting in the separation of NLS sequence from the beta-galactosidase and rendering a lower frequency of X-gal staining in the nucleus.

Wavelet analysis for brain-function imaging.

The authors present a new algorithmic procedure for the analysis of brain images. This procedure is specifically designed to image the activity and functional organization of the brain. The authors' results are tested on data collected and previously analyzed with the technique known as in vivo optical imaging of intrinsic signals. The authors' procedure enhances the applicability of this technique and facilitates the extension of the underlying ideas to other imaging problems (e.g., functional MRI). The authors' thrust is two fold. First, they give a systematic method to control the blood vessel artifacts which typically reduce the dynamic range of the image. They propose a mathematical model for the vibrations in time of the veins and arteries and they design a new method for cleaning the images of the vessels with the highest time variations. This procedure is based on the analysis of the singularities of the images. The use of wavelet transform is of crucial importance in characterizing the singularities and reconstructing appropriate versions of the original images. The second important component of the authors' work is the analysis of the time evolution of the fine structure of the images. They show that, once the images have been cleaned of the blood vessel vibrations/variations, the principal component of the time evolutions of the signals is due to the functional activity following the stimuli. The part of the brain where this function takes place can be localized and delineated with precision.

Isolated extramedullary relapse of acute lymphoblastic leukemia presenting as an intraspinal mass.

Leptomeningeal relapse is a common finding in acute lymphoblastic leukemia (ALL), but a solid intraspinal mass with cord compression as the sole site of extramedullary relapse is unusual. We report an adult patient with ALL, after 2 years of complete remission, who developed a spinal cord compression due to an intraspinal mass as a first manifestation of extramedullary relapse. Manifestation of first relapse in ALL presenting as an intraspinal mass is rare and may be added to other unusual extramedullary sites of relapse.

Neurofibromatosis, acute myelomonocytic leukemia, and disseminated tuberculosis: an adult case report.

Leukemia associated with neurofibromatosis has been reported to be predominantly nonlymphocytic and limited to childhood; it is rare in adulthood. An adult case is reported; the patient had nonfamilial peripheral neurofibromatosis (NF) (von Recklinghausen's disease), contracted acute myelomonocytic leukemia and disseminated tuberculosis (TB). After a four-month periods of anti-TB medication that disease was much improved, but the leukemic picture was still progressing. Chemotherapy was not given. This case further illustrated an association between acute nonlymphocytic leukemia (ANLL) and neurofibromatosis type 1 (NF-1) in adulthood. An attempt was made also to explain the relationship between disseminated tuberculosis and, in this instance, hematological abnormalities.

[Sézary syndrome].

Sézary syndrome is a form of leukemia-lymphoma characterized clinically by erythroderma, pruritus, adenopathy, and circulating atypical cells with cerebriform nuclei. Histologically, atypical lymphocytes in the dermis and Pautrier's microabscesses are often present in skin biopsy specimens. We herein report a typical case of Sézary syndrome showing T-suppressor-cell characteristics, and related literatures are reviewed.

DAE (daunorubicin, Ara-C, and etoposide) and intermediate dose Ara-C for remission induction and consolidation treatment of adult patients with acute myeloid leukemia.

Fifty-one patients (age 18-73 years) with acute myeloid leukemia were treated with daunorubicin, cytarabine, and etoposide in an age-adjusted protocol, with patients older than 50 receiving fewer days of therapy. Complete remission (CR) occurred in 66% of the patients (34 of 51 patients). Patients 50 years of age and younger achieved a 74% CR rate (23 of 31 patients) compared to a 55% CR rate (11 of 20 patients) in older patients. Of the 34 complete responders, 11 (32%) refused consolidation therapy and received traditional Chinese herbal medicine. All of these 11 patients relapsed after a short remission duration (median, 3.8 months) and died. The median remission duration and median overall survival of 23 complete responders receiving at least two courses of consolidation therapy were 10.1 and 19.8 months, respectively. The actuarial 3-year disease-free survival for these 23 complete responders was 21 +/- 9%. Myelosuppression was the major toxicity, and nonhematological side effects were acceptable. The regimen appeared to have acceptable toxicity, and its efficacy was comparable with that of standard regimens with long-term maintenance therapy.

Ketoconazole and high-dose methylprednisolone predisposing to cyclosporine-induced seizures: report of 3 cases.

Three consecutive cases of severe aplastic anemia undergoing immunosuppressive therapy with cyclosporin A (CyA) and high-dose methylprednisolone (HDMP) developed grand mal seizures after receiving ketoconazole treatment. All the seizures were reversed after transient discontinuation of those drugs. To our knowledge, it has not been reported as yet that the combination of ketoconazole and HDMP may considerably increase the risk of CyA-induced seizure. We would advise that ketoconazole and HDMP not be taken concomitantly with CyA treatment, and whenever ketoconazole therapy is needed, CyA be started with as small a dose as possible.

Immunophenotyping of myeloma cells with immunoalkaline phosphatase technique.

An immunoalkaline phosphatase (IAP) technique was used to determine the class of cytoplasmic immunoglobulin presenting in the malignant plasma cells of patients with multiple myeloma. Using monoclonal antibodies against different human immunoglobulins (Igs) as the primary antibodies, and calf intestinal phosphatase as the enzymatic indicator. The presence of monoclonal immunoglobulin was demonstrated within the cytoplasm of malignant plasma cells. These results correlate well with the electrophoretic patterns of the Igs present in the serum samples of these patients. This IAP technique is suggested as a practical method for evaluating the immunophenotype of multiple myeloma.