Strongyloides stercoralis infection in allogeneic stem cell transplant: a case report and review of the literature.

Strongyloides stercoralis infections may be documented in low-endemicity areas, particularly in immigrants from endemic areas. The case of a patient from Bangladesh, an immigrant to Italy who developed a S. stercoralis infection after allogeneic stem cell transplant, is described, and 7 further cases are reviewed. Because of the atypical clinical presentation, the low predictive role of the eosinophil count, and the low sensitivity of the microbiological tests, diagnosis of strongyloidiasis is a challenging problem. When a case of S. stercoralis infection is suspected, previous exposure may be the only clue to guide the diagnostic approach.

Prevalence of human herpesvirus-6 chromosomal integration (CIHHV-6) in Italian solid organ and allogeneic stem cell transplant patients.

The unique phenomenon of human herpesvirus-6 (HHV-6) chromosomal integration (CIHHV-6) may account for clinical drawbacks in transplant setting, being misinterpreted as active infection and leading to unnecessary and potentially harmful treatments. We have investigated the prevalence of CIHHV-6 in 205 consecutive solid organ (SO) and allogeneic stem cell transplant (alloSCT) Italian patients. Fifty-two (38.5%) of 135 solid organ transplant (SOT) and 16 (22.8%) of 70 alloSCT patients resulted positive for plasma HHV-6 DNA by real-time polymerase chain reaction. Seven SOT and three alloSCT patients presented HHV-6-related diseases, requiring antivirals. Two further patients (0.9%) were identified, presenting high HHV-6 loads. The quantification of HHV-6 on hair follicles disclosed the integrated state, allowing the discontinuation of antivirals. Before starting specific treatments, CIHHV-6 should be excluded in transplant patients with HHV-6 viremia by the comparison of HHV-6 loads on different fluids and tissues. Pretransplantation screening of donors and recipients may further prevent the misdiagnosis of CIHHV-6.

Activation of c-myb expression by phytohemagglutinin stimulation in normal human T lymphocytes.

The expression of c-myb in normal human T lymphocytes directly derived from a normal subject and not adapted to continuous growth in culture was found to be markedly increased after phytohemagglutinin stimulation. In the same cells, the expression of c-myc mRNA is a much earlier event compared with the appearance of c-myb mRNA, which takes place soon after that of histone H3 mRNA. The increase in c-myb expression was not due to a particular T-lymphocyte subset, as shown by in situ hybridization assays.

Gene expression profiling of acute promyelocytic leukaemia identifies two subtypes mainly associated with flt3 mutational status.

Acute promyelocytic leukaemia (APL) is a well-defined disease characterized by a typical morphology of leukaemic cells, the presence of t(15;17) translocation and the unique sensitivity to the differentiating effect of all-trans retinoic acid. Nevertheless, some aspects are variable among APL patients, with differences substantially related to morphological variants, peripheral leukocytes count, the presence of a disseminated intravascular coagulopathy, different PML/RARalpha isoforms (long, variable or short) and Fms-like tyrosine kinase 3 (Flt3) mutations. In order to better define this variability, we investigated the gene expression profiles of 18 APL cases revealing, besides a high uniformity in gene expression pattern, the presence of few robust differences among patients able to identify, by an unsupervised analysis, two major clusters of patients characterized by different phenotypes (hypogranular M3v vs classical M3) and by the presence or absence of Flt3 internal tandem duplications (ITDs). Further supervised analysis confirmed that Flt3 status was the APL parameter best associated with these two subgroups. We identified, between Flt3 wild-type and Flt3-ITDs subsets, 147 differentially expressed genes that were involved in the cytoskeleton organization, in the cell adhesion and migration, in the proliferation and the coagulation/inflammation pathways as well as in differentiation and myeloid granules constitution suggesting a role of Flt3 mutations in the pathogenesis and clinical manifestations of APL.

Use of resorbable implants for symptomatic cervical spondylosis: experience on 16 consecutive patients.

AIM: The aim of this study was to evaluate the results of a consecutive series of 16 patients affected by degenerative cervical spondylosis and operated on by anterior cervical discectomy and fusion (ACFD) by means of anterior bioresorbable plate and screws. Further, the authors compared the results in these patients with a series of 13 patients also affected by degenerative cervical spondylosis in whom arthrodesis was obtained by means of cages without plates.\ METHODS: The series included 8 males and 8 females aging from 37 to 69 years, operated from June 2003 to September 2004. They showed signs of cervical myelopathy, radiculopathy or both. The ACDF was performed with the insertion of dense cancellous allograft and application of anterior bioresorbable plate and screws (group A). The group B series included 9 males and 4 females aging from 50 to 77 years, all affected by the same pathology of group A patients and operated on in the same period of time. In these cases the ACDF was followed by the insertion of cages without anterior plates. RESULTS: The retrospective analysis of our series showed lack of soft tissue reaction, with safeguarding of the vertebral body and disc space height. The degree of alignment of the cervical spine was also preserved, with a good rate of fusion and a good clinical outcome in both series of patients. CONCLUSION: The use of a cervical plate increase stability and rate of fusion when added to the interbody device; while the use of a metallic plate may be responsible for several shortcomings, a resorbable plate may overcome these problems.

Pathophysiology of bleeding in surgery.

Bleeding is a major surgical complication. Although mortality rates of 0.1% are observed for surgical procedures, it may be 5% to 8% for elective vascular surgery, and increase to 20% in the presence of severe bleeding. In major surgery for liver diseases, as well as in cardiac surgery, excessive blood loss is associated with increased mortality, morbidity, and intensive care stay. Approximately 75% to 90% of intraoperative and early postoperative bleeding is due to technical factors. However, in some cases either acquired or congenital coagulopathies may favor, if not directly cause, surgical hemorrhage. Uncontrolled bleeding leads to a combination of hemodilution, hypothermia, consumption of clotting factors, and acidosis, which in turn worsen the clotting process, further exacerbating the problem in a vicious bloody circle. At present, the standard treatment for surgical bleeding is the rapid control of the source of bleeding by either surgical or radiological techniques. Blood-derived products as well as hemostatic agents, such as aprotinin, tranexamic acid, and DDAVP, are widely used to improve hemostatic balance in bleeding patients. Recombinant activated factor VII (rFVIIa) has been reported to be effective for the treatment of surgical or traumatic massive bleeding unresponsive to conventional therapy. Although most reports are anecdotal, and therefore exposed to a "positive" selection bias, the number of cases is impressive, strongly suggesting that in such patients rFVIIa may afford a hemostatic advantage beyond that of conventional replacement therapy.

Expression of c-myb protooncogene and other cell cycle-related genes in normal and neoplastic human colonic mucosa.

The expression of c-myb, c-myc, histone H3, and ornithine decarboxylase genes was examined by Northern blot analysis in the normal and neoplastic mucosa of ten subjects affected by colon cancer. The mRNA levels of c-myb protooncogene were detected at low levels in all normal samples but were increased in the neoplastic mucosa of six cases in comparison to the normal counterpart. In five of these six cases the mRNA levels of c-myc, histone H3, and ornithine decarboxylase mRNAs were also increased, suggesting that there is a relation between the high expression of c-myb and the fraction of cycling neoplastic cells.

Abundance of the primary transcript and its processed product of growth-related genes in normal and leukemic cells during proliferation and differentiation.

The relative abundance of primary transcript and mature mRNA of the c-myc, calcyclin, S14 ribosomal protein, and rRNA genes was determined densitometrically after reverse transcriptase-polymerase chain reaction and Northern blotting analysis in resting and mitogen-stimulated lymphocytes, proliferating and terminally differentiated HL-60 cells, and leukemic blast cells. Transcription and processing of c-myc and rRNA gene transcripts increased proportionally after mitogen stimulation, whereas these processes were independent of cell cycling status in the case of the S14 gene. Normal lymphocytes showed an unexpectedly large amount of primary transcript of the calcyclin gene, whereas the corresponding mRNA was undetectable. The abundance of c-myc, calcyclin, and S14 mRNA in terminally differentiated HL-60 cells decreased sharply, compared to their proliferating counterparts. This decrease reflected post-transcriptional modulation, since the abundance of precursor remained essentially unchanged. After HL-60 differentiation, the 32S rRNA levels remained relatively high, whereas the 45S primary transcript almost disappeared. Leukemic blast cells displayed highly variable precursor/mRNA ratios of c-myc, calcyclin, and S14 genes but consistently high ratios of 32S to 45S RNA, suggesting that the cleavage rate of the 32S rRNA was sharply reduced in these cells, resulting in an accumulation of this molecule. These results suggest the importance of efficient processing of primary transcript to generate adequate functional mRNA, thus regulating gene expression. Furthermore, in terminally differentiated cells and leukemic blast cells a stabilization of the primary transcript without efficient processing can be observed. The role of the stabilization of the primary transcript in terminal differentiation is further supported by the results of run-off transcription, indicating a sharp decrease of c-myc and calcyclin transcription rate in retinoic acid/dimethyl sulfoxide-treated HL-60 cells.

Accumulation of giant heterogeneous RNA molecules in acute myeloid leukemia blast cells.

Time course and "chase" experiments showed that, after incubation of acute myeloid leukemia blast cells with a labeled RNA precursor, a large proportion of radioactivity remained associated with RNA molecules larger than 45 S even after several hr. Double-labeling experiments with [5-3H]uridine and [methyl-14C]methionine indicated that unmethylated giant heterogeneous RNA larger than 45 S is processed much more slowly than the 45 S ribosomal precursor, so that relatively large amounts of fairly stable RNA of the former class accumulate in the cell. The measurement of labeled giant heterogeneous RNA molecules bound to polyuridylate-fiberglass filters showed that molecules carrying polyadenylate segments seemingly turn over faster than those lacking polyadenylate.

Immunological assay of double-helical segments in RNA fractions of different molecular size extracted from acute myeloid leukemia blast cells.

Whole-cell RNA, extracted from acute myeloid leukemia blast cells, was fractionated by sedimentation through sucrose gradients. The proportion of double-helical segments present in each fraction was then determined by a quantitative microcomplement fixation assay that specifically measures double-helical RNA. Sizable amounts of double-helical segments were detected in all fractions of cellular RNA corresponding to S values higher than approximately 20. In all cell populations examined the highest proportion of double-helical segments was found in RNA fractions sedimenting faster then the 45 S ribosomal precursors RNA, i.e., in fractions including only heterogeneous nuclear RNA.

Noncoordinated expression of S6, S11, and S14 ribosomal protein genes in leukemic blast cells.

The steady state levels of mRNAs codying for the ribosomal proteins S6, S11, and S14 have been evaluated in quiescent and proliferating human fibroblasts and in resting and proliferating human peripheral blood mononuclear cells. It was found that the amounts of ribosomal protein mRNA are very similar and are not increased by serum or mitogen stimulation. The constitutive expression of these genes appears to be coordinately regulated and it is not modified after protein synthesis inhibition by cycloheximide. The ribosomal protein mRNA was also assayed in 15 different populations of human leukemic blast cells. In these populations the abundance of each ribosomal protein mRNA is remarkably different from the other. The results of our present experiments indicate that the expression of the three ribosomal protein genes undergoes independent noncoordinated changes in the large majority of the leukemic populations studied.

Growth-dependent expression of human Mr 53,000 tumor antigen messenger RNA in normal and neoplastic cells.

We have investigated the expression of Mr 53,000 protein (p53) in total RNA isolated from human peripheral blood mononuclear cells stimulated by phytohemagglutinin, in serum-stimulated human diploid fibroblasts, and in normal and tumor cells of human epithelial colon tissue. We have found that the expression of p53 messenger RNA is growth regulated in human cells following kinetics similar to that previously shown in mouse 3T3 cells, and is increased in the large majority of colon adenocarcinomas in comparison to adjacent normal mucosa and adenoma. This increased expression of p53 is accompanied by a nearly proportional increase in the expression of histone H3. As the expression of histone H3 is restricted to the S phase of the cell cycle and therefore measures the growth fraction of a given population, we suggest that the increased expression of p53 observed in the large majority of colon tumors simply reflects the increased number of cycling cells frequently found in a neoplastic tissue. At variance with these findings a true overexpression of p53 was detected in one SV40-transformed human fibroblasts cell line.

Ratios between the abundance of messenger RNA and the corresponding protein of two growth-related genes, c-myc and vimentin, in leukemia blast cells.

The abundance of the mRNAs of two growth-related genes, vimentin and c-myc, and that of the corresponding proteins have been studied in unstimulated and phytohemagglutinin-stimulated lymphocytes as well as in 18 populations of leukemic blast cells. The quantitative assay was carried out by densitometric scanning of Northern and Western blots. In normal lymphocytes the mRNA and the protein of both genes were almost undetectable. The phytohemagglutinin stimulation led to a sharp increase of the mRNA and the proteins of vimentin and c-myc. The increase was followed by a progressive fall of the gene products. The rate of decrease of the two mRNAs was similar to that of the corresponding proteins. In some leukemic populations very similar amounts of the vimentin protein were accompanied by amounts of the mRNA differing at least 25 times. Not unlikely, very similar amounts of p62c-myc corresponded to mRNA abundances differing at least 16 times. The coordinated biogenesis of both messenger RNAs and proteins, which occurs in mitogen-stimulated lymphocytes, is substituted, in approximately 30% of the leukemic blast cell populations, by molecular events leading to the accumulation of an excess of mRNA.

Human herpesvirus 6 (HHV-6) ORF-1 transactivating gene exhibits malignant transforming activity and its protein binds to p53.

The 357 amino acid open reading frame 1 (ORF-1), also designated DR7, within the SalI-L fragment of human herpesvirus 6 (HHV-6) exhibited transactivation of the human immunodeficiency virus type 1 (HIV-1) long terminal repeat (LTR) promoter and increased HIV-1 replication (Kashanchi et al., Virology, 201, 95-106, 1994). In the current study, the SalI-L transforming region was localized to the SalI-L-SH subfragment. Several ORFs identified in SalI-L-SH by sequence analysis were cloned into a selectable mammalian expression vector, pBK-CMV. Only pBK/ORF1 transformed NIH3T3 cells. Furthermore, cells expressing ORF-1 protein produced fibrosarcomas when injected into nude mice, whereas control cells, expressing either no ORF-1 protein or C-terminal truncated (after residue 172) ORF-1 protein, were not tumorigenic. Western blot analysis of proteins extracted from the tumors revealed ORF-1 protein. Additional studies indicated that ORF-1 was expressed in HHV-6-infected human T-cells by 18 h. Co-immunoprecipitation experiments showed that ORF-1 protein bound to tumor suppressor protein p53, and the ORF-1 binding domain on p53 was located between residues 28 and 187 of p53, overlapping with the specific DNA binding domain. Functional studies showed that p53-activated transcription was inhibited in ORF-1, but not in truncated ORF-1, expressing cells. Importantly, the truncated ORF-1 mutant also failed to cause transformation. Analysis of several human tumors by PCR revealed ORF-1 DNA sequences in some angioimmunoblastic lymphadenopathies, Hodgkin's and non-Hodgkin's lymphomas and glioblastomas. The detection of ORF-1 sequences in human tumors, while not proof per se, is a prerequisite for establishing its role in tumor development. Taken together, the results demonstrate that ORF-1 is an HHV-6 oncogene that binds to and affects p53. The identification of both transforming and transactivating activities within ORF-1 is a characteristic of other viral oncogenes and is the first reported for HHV-6.

Sodium chloride reflection coefficient in rabbit gall bladder.

By means of the Kedem-Katchalsky thermodynamic description of active transport, a relationship has been derived between the apparent reflection coefficient and the Staverman reflection coefficient for passive transport of a solute which is both actively and passively transported. The relationship between volumetric flow and its driving forces, containing the Staverman reflection coefficient, was tested for sodium chloride in rabbit gall bladder and the reflection coefficient was evaluated.

Reassociation kinetics of the DNA of human acute leukemia cells.

Human DNA isolated from normal phytohaemagglutinin-stimulated human lymphocytes and from acute leukemia blast cells have been studied by renaturation techniques using hydroxyapatite binding and DNA hyperchromism. In the leukemic genome, the unique sequences account for 62% of the genome of leukemic DNA. Repetitive sequences may be subdivided into at least three fractions: (a) foldback sequences, which represent 5% of the genome; (b) sequences with high repetition frequency (3. 10(4) times on the average), which represent 12% of the genome; (c) sequences with low repetition frequency (10 times on the average), which represent 16% of the genome. The average length of the repetitive sequences is evaluated to be between 200 and 500 nucleotides. There are at least two patterns of interspersion of repetitive sequences with unique sequences of different length: short (about 2000 nucleotides on average) and long (not defined). The results of our experiments on DNA from normal phytohaemagglutinin-stimulated human lymphocytes are in close agreement with those reported by other authors studying different types of human cells. The human leukemic DNA, as far as the parameters that have been studied, does not significantly differ from normal human DNA.

Detection of circulating tumor cells by reverse transcriptase polymerase chain reaction of maspin in patients with breast cancer undergoing conventional-dose chemotherapy.

PURPOSE: To establish, in patients with breast cancer subjected to primary conventional chemotherapy and enrolled in a prospective study, the mobilizing effect of therapy on potentially neoplastic cells by means of a reverse transcriptase polymerase chain reaction (RT-PCR) assay for mRNA of maspin, a protein related to the serpin family of protease inhibitors. PATIENTS AND METHODS: Peripheral-blood samples were collected from 30 patients with histologically proven breast cancer before and 4 and 8 days after conventional chemotherapy for three consecutive courses. A total of 216 samples were screened for the presence of maspin mRNA by RT-PCR. RESULTS: Before therapy, all samples but one were negative. After chemotherapy, 11 patients (38%) had positive samples. No difference in the rate of positivity was observed between groups defined according to initial stage, type of chemotherapy, Ki-67-related proliferative activity, or CA 15.3 expression. CONCLUSION: Our results confirm that RT-PCR for maspin mRNA is a sensitive assay for the study of circulating potentially neoplastic mammary cells in patients with breast cancer. Moreover, our findings indicate a marked effect of conventional-dose chemotherapy on the mobilization of these cells in breast tumors. In our series of patients, this phenomenon does not seem to be associated with other known risk factors. Finally, the data suggest, without proving, an association between the presence of circulating maspin positive cells and a higher risk of disease progression. If this association could be confirmed, then the assay could have prognostic significance. However, larger confirmatory studies are necessary.

Expression of oncogenes and cell cycle related genes in acute and chronic leukemias.

The authors have assayed the level of expression of several cell-cycle related genes in several populations of circulating myeloid leukemic blast cells. The genes explored included oncogenes such as c-myc, c-myb, p53, and cell-cycle-related genes such as vimentin, calcyclin, ornithine decarboxylase (ODC) and histone H3. Particular attention was given to analysis of the relationship existing between the mRNA levels of the histone H3 gene, which is expressed specifically in the S phase of the cell cycle, and the levels of other genes that are expressed in different stages of the G1 phase. Remarkable differences were observed among the different cases indicating that a differential expression of cell-cycle-related genes characterizes many acute leukemias. This differential expression is reflected in an altered ratio among G1-related genes and the H3 histone gene. The large fraction of leukemic cells which does not express histone H3 and therefore is functionally noncycling, shows a heterogeneous pattern of G1-related gene expression. This reflects the inability of most leukemic cells to progress through the G1 phase into the S phase of the cell cycle. This inability represents an abnormality of the cell cycle. It is concluded that the study of the expression of cell-cycle genes and protooncogenes in in understanding how leukemic cells enter a state of proliferation arrest, which appears to occur in a large fraction of leukemic cells.

Detection of low abundance mRNA of myeloid specific genes in cells of acute and chronic lymphoid leukemias by cRNA hybridization.

The hybridization to a complementary RNA (cRNA) probe both in situ and in solution was used to assay tiny amounts of mRNA of the lactoferrin (LF) and myeloperoxidase (MPO) genes in normal bone marrow cells and in acute and chronic lymphoid leukemias. Evidence is reported that this technique is much more sensitive than the standard Northern blot technique. The LF mRNA was detectable in three of seven cases of acute lymphoblastic leukemia (ALL) and in three of seven cases of chronic lymphocytic leukemia (CLL). Four cases of ALL were also positive when tested with the MPO cRNA. It is apparent from these results that myeloid specific mRNA, different from MPO, may be detected in leukemic cells with lymphoid phenotype using a method more sensitive than the Northern blot technique. Whether or not the molecular events observed in these cell populations reflect events physiologically occurring rather than a deregulation of gene expression associated to leukemogenesis remains to be established.

Hepatitis C virus infection in subsets of neoplastic lymphoproliferations not associated with cryoglobulinemia.

Hepatitis C virus (HCV) is both hepatotropic and lymphotropic and a clear-cut association has been proposed between HCV infection and mixed cryoglobulinemia (MC), a benign lymphoproliferative disorder, which sometimes evolves into a frank malignant B cell non-Hodgkin's lymphoma (B-NHL). Moreover, in the presence of antibodies to HCV, as well as of HCV-specific genomes has been reported in the sera of over 37% patients with B-NHL, not associated with MC. Thus, we decided to perform both a serologic and a molecular study to give insights into a possible relationship between HCV infection and neoplastic lymphoproliferations. We used ELISA and RIBA tests to show that anti-HCV antibodies were present in the serum of 29 out of 69 unselected B-NHL patients (42%), while seropositivity in a healthy population was about 1%. The prevalence of anti-HCV antibodies was low in definite subsets of B lymphoid disorders, including multiple myeloma, Waldenström's macroglobulinemia and monoclonal gammopathies of undetermined significance. Then, using reverse transcriptase polymerase chain reaction, we detected HCV sequences directly in the pathologic lymph node biopsies in 13 out of 34 B-NHL cases, and in particular in six out of eight low-grade lymphomas of MALT type and in five out of eight centroblastic-centrocytic follicular lymphomas. In contrast, the peripheral blood samples from 10 B cell chronic lymphocytic leukemia patients resulted negative for the presence of HCV genomes. Similarly, viral sequences were absent in 10 T cell NHL, while only one out of the 14 Hodgkin's disease cases tested resulted positive. Finally, we used a PCR-based assay to characterize the genotypes (I-IV) present in the positive lymphomatous tissues. The presence of both serologic and molecular markers of HCV infection in a high percentage of certain types of B-NHL, not associated with cryoglobulinemia, and its absence from other lymphoproliferative diseases extends the spectrum of HCV-associated lymphoproliferations arguing in favor of some role of this viral infection in the pathogenesis of the malignant proliferation of definite B lymphoid populations.