A novel nuclear protein, 5qNCA (LOC51780) is a candidate for the myeloid leukemia tumor suppressor gene on chromosome 5 band q31

Interstitial deletion or loss of chromosome 5, del(5q) or -5, is a frequent finding in myeloid leukemias and myelodysplasias, suggesting the presence of a tumor suppressor gene within the deleted region. In our search for this gene, we identified a candidate, 5qNCA (LOC51780), which lies within a consistently-deleted segment of 5q31. 5qNCA expresses a 7.2-kb transcript with a 5286-bp open reading frame which is present at high levels in heart, skeletal muscle, kidney, placenta, and liver as well as CD34+ cells and AML cell lines. 5qNCA encodes a 191-kD nuclear protein which contains a highly-conserved C-terminus containing a zinc finger with the unique spacing Cys-X2-Cys-X7-His-X2-Cys-X2-Cys-X4-Cys-X2-Cys and a jmjC domain, which is often found in proteins that regulate chromatin remodeling. Expression of 5qNCA in a del(5q) cell line results in suppression of clonogenic growth. Preliminary sequence results in AML and MDS samples and cell lines has revealed a possible mutation in the KG-1 cell line resulting in a THR to ALA substitution that has not been found in over 100 normal alleles to date. We propose 5qNCA is a good candidate for the del(5q) tumor suppressor gene based on its predicted function and growth suppressive activities, and suggest that further mutational and functional study of this interesting gene is warranted.

P15INK4B gene methylation and expression in normal, myelodysplastic, and acute myelogenous leukemia cells and in the marrow cells of cured lymphoma patients

P15INK4B methylation and expression was studied in bone marrow cells obtained from normal individuals, from patients who had been cured of lymphoma, and from patients with either MDS or AML. The level of p15 methylation was very low in normal BM cells and in CD34+ and CD34- subpopulations (0-6.5%; med, = 2.5%). P15INK4B transcripts were present in each of these cell populations. In contrast, methylation was the usual situation in MDS and AML marrows. The presence of methylation of the p15INK4B gene did not always indicate an absence of expression nor was expression always present if methylation was absent. P15INK4B methylation was studied in the marrows of nine patients (one studied twice) who had been cured of lymphoma and in whom hemopoiesis was believed to be normal. Increased methylaton was present in all 10 marrows. These data indicate that p15INK4B methylation is likely to be a very early event in the development of the secondary hematologic disorders.

Microbiologic effectiveness of hand washing with soap in an urban squatter settlement, Karachi, Pakistan

We conducted a study in a squatter settlement in Karachi, Pakistan where residents report commonly washing their hands to determine if providing soap, encouraging hand washing, and improving wash-water quality would improve hand cleanliness. We allocated interventions to 75 mothers and collected hand-rinse samples on unannounced visits. In the final model compared with mothers who received no hand-washing intervention, mothers who received soap would be expected to have 65% fewer thermotolerant coliform bacteria on their hands (95% CI 40%, 79%) and mothers who received soap, a safe water storage vessel, hypochlorite for water treatment, and instructions to wash their hands with soap and chlorinated water would be expected to have 74% fewer (95% CI 57%, 84%). The difference between those who received soap alone, and those who received soap plus the safe water vessel was not significant (P = 0.26). Providing soap and promoting hand washing measurably improved mothers' hand cleanliness even when used with contaminated water.

Effect of rosuvastatin on low-density lipoprotein cholesterol in patients with hypercholesterolemia

Rosuvastatin is a new, synthetic, orally active statin, with marked low-density lipoprotein (LDL) cholesterol-lowering activity. We conducted 2 dose-ranging studies. In the first study, after a 6-week dietary run-in, 142 moderately hypercholesterolemic patients were randomized equally to receive double-blind placebo or rosuvastatin 1, 2.5, 5, 10, 20, or 40 mg or open-label atorvastatin 10 or 80 mg once daily for 6 weeks; in the second study, conducted to extend the rosuvastatin dose range, 64 patients were randomized to double-blind, once-daily placebo or rosuvastatin 40 or 80 mg (1:1:2 ratio) for 6 weeks. Data from both studies were combined for analysis of lipid effects. No statistical comparison of atorvastatin arms with placebo or rosuvastatin was performed. Rosuvastatin was associated with highly significant dose-dependent reductions in LDL cholesterol compared with placebo (p <0.001); decreases ranged from 34% (1 mg) to 65% (80 mg). Linear regression analysis indicated an additional 4.5% LDL cholesterol reduction for each doubling of the rosuvastatin dose. Across the dose range, approximately 90% of LDL cholesterol reduction occurred within the first 2 weeks of treatment. Significant, dose-dependent reductions in total cholesterol and apolipoprotein B with rosuvastatin were also observed (p <0.001). High-density lipoprotein cholesterol increases and triglyceride reductions were consistently observed and statistically significant at some dose levels. All lipid ratios were significantly reduced at all rosuvastatin dose levels (p <0.001). Adverse events were similar across placebo and active treatments. No significant increases in alanine aminotransferase or creatine kinase were seen in any patient. Over 6 weeks, rosuvastatin produced large, rapid, dose-dependent LDL cholesterol reductions and was well tolerated in hypercholesterolemic patients.

Thalidomide produces transfusion independence in long-standing refractory anemias of patients with myelodysplastic syndromes

Thalidomide was administered to 83 patients with myelodysplastic syndrome (MDS), starting at 100 mg by mouth daily and increasing to 400 mg as tolerated. Thirty-two patients stopped therapy before 12 weeks (minimum period for response evaluation), and 51 completed 12 weeks of therapy. International Working Group response criteria for MDS were used to evaluate responses. Intent-to-treat (ITT) analysis classified all off-study patients as nonresponders. Off-study patients belonged to a higher risk category (P =.002) and had a higher percentage of blasts in their pretherapy bone marrow than patients who completed 12 weeks of therapy (P =.003). No cytogenetic or complete responses were seen, but 16 patients showed hematologic improvement, with 10 previously transfusion-dependent patients becoming transfusion independent. Responders had lower pretherapy blasts (P =.016), a lower duration of pretherapy platelet transfusions (P =.013), and higher pretherapy platelets (P =.003). Among responders, 9 had refractory anemia (RA); 5 had RA with ringed sideroblasts; and 2 had RA with excess blasts. By ITT analysis, 19% of patients (16 of 83) responded, and when only evaluable patients were analyzed, 31% (16 of 51) responded. It was concluded that thalidomide, as a single agent, is effective in improving cytopenias of some MDS patients, especially those who present without excess blasts. (Blood. 2001;98:958-965)

Presence of activation-related m-RNA for EBV and CMV in the bone marrow of patients with myelodysplastic syndromes

The bone marrow (BM) in myelodysplastic syndromes (MDS) undergoes pathobiological changes that mimic an inflammatory process, and hence, an infectious etiology was suspected in these disorders. In the present report, we examined the bone marrow mononuclear cells (BMMNC) of 19 MDS patients and seven normal donors for the expression of one latency-related (Latency membrane protein 1 (LMP-1) and immediate early protein (IEP)) and one activation-related (BZLF and DNA-Pol) m-RNA each for two herpes viruses, Epstein-Barr virus (EBV) and cytomegalovirus (CMV), respectively. Reverse transcriptase polymerase chain reaction was used for this purpose. The latency-related transcripts (EBV-LMP-1 and CMV-IEP) were present in all the MDS and normal specimens. Intriguingly, 10/19 MDS specimens ( approximately 53%) and 2/7 normal donors ( approximately 28%) were positive for active EBV-BZLF (P=0.0067), while 2/19 MDS specimens ( approximately 11%) with 1/7 normal ( approximately 14%) showed active CMV-DNA-Pol (P=0.1588). Later, from another set of MDS patients (n=7) and normal donors (n=4), BM stromal cultures were established, which, at a 75% confluency, were overlaid with cord blood mononuclear cells (CBMNC). IEP was detectable in the CBMNC before and after co-incubation with MDS, as well as normal stroma. So, it was also present both in MDS and normal stromal cells. The other three were absent both in MDS and normal stromal layers. In CBMNC though, active EBV-BZLF and CMV-DNA-Pol m-RNA were detectable in one of seven MDS co-cultures each, albeit from different patients. None of the normal co-cultures showed active virus, either in stroma or CBMNC. Thus, the present report demonstrates, for the first time, the presence of active herpes viruses in the BMMNC of MDS patients and reveals the ability of the MDS stroma to support the viral activation.

Cholesteatoma: an unusual presentation

A case is described of an extensive cholesteatoma presenting as a lump on the side of a patient's head overlying the squamous temporal bone, with erosion of the underlying bone and intracranial extension. The patient was otherwise asymptomatic. This case highlights the bone-eroding capacity of cholesteatoma and the vigilance required in assessing lumps on the head.

Mapping of the region of complement receptor (CR) 1 required for Plasmodium falciparum rosetting and demonstration of the importance of CR1 in rosetting in field isolates

The malaria parasite Plasmodium falciparum induces a number of novel adhesion properties in the erythrocytes that it infects. One of these properties, the ability of infected erythrocytes to bind uninfected erythrocytes to form rosettes, is associated with severe malaria and may play a direct role in the pathogenesis of disease. Previous work has shown that erythrocytes deficient in complement receptor (CR) 1 (CR1, CD35; C3b/C4b receptor) have greatly reduced rosetting capacity, indicating an essential role for CR1 in rosette formation. Using deletion mutants and mAbs, we have localized the region of CR1 required for the formation of P. falciparum rosettes to the area of long homologous repeat regions B and C that also acts as the binding site for the activated complement component C3b. This result raises the possibility that C3b could be an intermediary in rosetting, bridging between the infected erythrocyte and CR1. We were able to exclude this hypothesis, however, as parasites grown in C3-deficient human serum formed rosettes normally. We have also shown in this report that rosettes can be reversed by mAb J3B11 that recognizes the C3b binding site of CR1. This rosette-reversing activity was demonstrated in a range of laboratory-adapted parasite strains and field isolates from Kenya and Malawi. Thus, we have mapped the region of CR1 required for rosetting and demonstrated that the CR1-dependent rosetting mechanism occurs commonly in P. falciparum isolates, and could therefore be a potential target for future therapeutic interventions to treat severe malaria.

Cytogenetic and molecular diagnosis of chromosome 5 deletions in myelodysplasia

Deletions of chromosome 5, del(5q), are frequently observed in myelodysplasia (MDS). We evaluated molecular detection of loss of heterozygosity (LOH) as a diagnostic method to detect del(5q) in a series of 60 MDS cases at a single institution. LOH was compared to cytogenetics on the same clinical specimen, resolving ambiguous cases by fluorescent in situ hybridization (FISH) and additional LOH. There was poor concordance between molecular and cytogenetic results, but most discrepancies could be resolved by FISH and additional LOH. Molecular analysis was of low sensitivity because most cases contained a relatively high proportion of cells without del(5q), but it was accurate, while cytogenetics overestimated the proportion of cells with del(5q) and failed to detect some cases with complex rearrangements. Minor clones were detected both by FISH and LOH. Overall, we found an incidence of 23% (14 of 60 cases) for del(5q) in MDS. The results also suggest that there is a high degree of genetic heterogeneity in the cellular population of MDS. Although del(5q) is common in MDS, it may not be present in all cells, leading to diagnostic challenges.

Intramedullary apoptosis of hematopoietic cells in myelodysplastic syndrome patients can be massive: apoptotic cells recovered from high-density fraction of bone marrow aspirates

A higher percentage of apoptotic cells (apoptotic index or AI) is consistently found in bone marrow (BM) biopsies compared to BM aspirates of patients with myelodysplastic syndrome (MDS). Most studies have only investigated the low-density fraction (LDF) mononuclear cells from BM aspirates following density separation for AI determination. In the present study, both LDF and high-density fraction (HDF) cells for AI were examined by electron microscopy (EM) in 10 MDS patients and 4 healthy donors. Matched BM biopsies were subjected to AI detection by in situ end labeling (ISEL) of fragmented DNA. The results indicate that in LDF and HDF cells, AI is consistently higher in MDS patients (8.5% vs 1.5%, respectively; P =.039) compared to healthy donors (27% vs 4%, respectively; P =. 004). The BM biopsy AI was also higher in MDS patients than in healthy donors (3+ vs 0+, respectively; P =.036). In addition, in MDS patients, more apoptotic cells were found in HDF cells than in LDF cells (27% vs 8.5%, respectively;P =.0001). All stages of maturation, ranging from blasts to terminally mature cells belonging to all 3 lineages, were represented in the dying cells in both compartments. Using EM, typical Pelger-Huett-type cells appeared to be apoptotic granulocytes. Both LDF and HDF cells should be examined for an accurate estimation of apoptotic cells because AI would be underestimated if only the LDF cells were studied. Ultrastructural studies consistently show a higher AI in BM biopsies compared to BM aspirates despite the correction factor of HDF cells provided by AI. This may represent the actual extant state, which could conceivably be due to a higher concentration of proapoptotic signals in the biopsies. (Blood. 2000;96:1388-1392)

Anti-TNF therapies in rheumatoid arthritis, Crohn's disease, sepsis, and myelodysplastic syndromes

An attempt has been made in this article to summarize the state-of-the-art clinical experience with the use of anti-TNF therapies in four diseased states with special emphasis on myelodysplastic syndromes. Given the central role of TNF-alpha in initiating and perpetuating the chronic damage produced in the diseased organs by controlling a cascade of pro-inflammatory cytokines, as well as its acute role in sepsis, theoretically speaking, neutralization of this peptide was a natural therapeutic choice. Results of the initial clinical trials appear encouraging and sometimes dramatic in their efficacy. The mechanism of response however, is interesting in that even when TNF-alpha is directly targeted by a monoclonal antibody, the resulting benefits can frequently not be attributed to TNF suppression alone. Rather, it appears that a more general effect on the T-lymphocytes is also contributing to the responses being seen. This raises the new possibility of combining anti-cytokine and anti-T-cell strategies to treat at least the more chronic diseases such as Crohn's disease and myelodysplastic syndromes. Continued clinical trials testing these strategies are clearly warranted.

Nonapoptotic neurodegeneration in a transgenic mouse model of Huntington's disease

Huntington's disease (HD) is a fatal inherited neurodegenerative disorder characterized by personality changes, motor impairment, and subcortical dementia. HD is one of a number of diseases caused by expression of an expanded polyglutamine repeat. We have developed several lines of mice that are transgenic for exon 1 of the HD gene containing an expanded CAG sequence. These mice exhibit a defined neurological phenotype along with neuronal changes that are pathognomonic for the disease. We have previously observed the appearance of neuronal intranuclear inclusions, but did not find evidence for neurodegeneration. In this study, we report that all lines of these mice develop a late onset neurodegeneration within the anterior cingulate cortex, dorsal striatum, and of the Purkinje neurons of the cerebellum. Dying neurons characteristically exhibit neuronal intranuclear inclusions, condensation of both the cytoplasm and nucleus, and ruffling of the plasma membrane while maintaining ultrastructural preservation of cellular organelles. These cells do not develop blebbing of the nucleus or cytoplasm, apoptotic bodies, or fragmentation of DNA. Neuronal death occurs over a period of weeks not hours. We also find degenerating cells of similar appearance within these same regions in brains of patients who had died with HD. We therefore suggest that the mechanism of neuronal cell death in both HD and a transgenic mouse model of HD is neither by apoptosis nor by necrosis.

Cytokine production by in vitro processed and unprocessed haematopoietic cells

The studies described here demonstrate that in vitro processing of cells before extraction of RNA has a major effect on the number and type of cytokine transcripts present within MDS and leukemia cells. Transcripts for GM-CSF, a cytokine whose production by leukemia cells is believed to play an important role in the pathogenesis of leukemia, was not detectable in 12/13 unprocessed AML specimens, in 12/12 MDS specimens, or in 7/7 CML specimens but once detected in many specimens after processing. These data strongly suggest that leukemia cell production of GMCSF rarely occurs in vivo.

Comparative efficacy of risperidone and clozapine in the treatment of patients with refractory schizophrenia or schizoaffective disorder: a retrospective analysis

BACKGROUND

Clozapine is effective in up to 60% of patients with refractory schizophrenia, whereas the efficacy of risperidone remains unknown. This retrospective study examined the relative efficacy of these drugs in chronically institutionalized patients refractory to conventional antipsychotic agents.

METHOD

A total of 24 patients who at different time periods had received adequate trials of both clozapine and risperidone and met our inclusion criteria for minimum dose and duration of each trial were included; for clozapine, a minimum dose of 300 mg/day had to be maintained for at least 12 weeks, and for risperidone, a minimum dose of 6 mg/day for at least 6 weeks. Information obtained from systematic retrospective chart review was blindly rated by 2 psychiatrists using the 7-point Clinical Global Impressions-Improvement (CGI-I) scale on overall clinical state and along specific symptom domains of positive symptoms, negative symptoms, and aggressive behavior.

RESULTS

The mean +/- SD dose was 520+/-94 mg/day for clozapine and 7.5+/-2.2 mg/day for risperidone. Fourteen patients (58%) were classified as responders to clozapine, while 6 (25%) responded to risperidone (CGI-I score of 1 or 2); on specific symptom domains, response rates to clozapine were 38% (9/24) on positive symptoms, 29% (7/24) on negative symptoms, and 71% (12/17) on aggressive behavior. For risperidone, response rates were 17% (4/24) on positive symptoms, 8% (2/24) on negative symptoms, and 41% (7/17) on aggressive behavior.

CONCLUSION

The results of this study support the utility of first giving a risperidone trial in a treatment algorithm for refractory patients because of its better risk/benefit profile compared with clozapine. Clozapine, however, remains our gold standard in the management of these patients.

Signal antonymy unique to myelodysplastic marrows correlates with altered expression of E2F1

Myelodysplastic syndromes (MDS) have previously been reported to show competitively high rates of apoptosis and proliferation in the bone marrow (BM). Using a double-labelling technique in the present study, we demonstrated that a significantly high number of S-phase cells were simultaneously apoptotic (signal antonymy; SA) in MDS (mean +/- s.e.m. 53.5 +/- 6.7%, n = 24, P < 0.001). In contrast, SA was negligible in all other specimens studied, including normal control BM (n = 13) from non-Hodgkin's lymphoma (NHL) patients, BM from patients with de novo acute myelogenous leukaemia (1'AML; n = 5), or secondary AML that had transformed from MDS (2'AML; n = 10), or the solid tumours from patients with NHL (n = 9) or head and neck squamous cell carcinoma (HNSCC; n = 10). Subsequently, the expression of a transcription factor, E2F1, was studied in density-separated BM aspirate mononuclear cells from MDS patients (n = 9) and a normal control. Two separate sets of primers were used that recognized the regulatory retinoblastoma (Rb) protein-binding region and the functional DNA-binding region of E2F1. Interestingly, although the latter manifested the expected band (280 bp) in all samples, the Rb-specific primers showed the expected band (380 bp) in the normal and in 4/9 MDS specimens. Two other MDS specimens also showed a smaller band ( approximately 325 bp), whereas 3/9 MDS patients showed exclusively the smaller band. The levels of SA were significantly higher in those MDS cases that showed the smaller Rb-specific band either alone or in addition to the expected band (median 19.5%, n = 4, P = 0.037) than in those showing exclusively the expected band (median 0.4%, n = 3). Our present studies show SA as a characteristic feature of MDS and, importantly, demonstrate its link with an altered expression of E2F1 in some MDS patients.