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Mesangiogenic progenitor cells (MPCs) are a very peculiar population of cells present in the human adult bone marrow, only recently discovered and characterized. Owing to their differentiation potential, MPCs can be considered progenitors for mesenchymal stromal cells (MSCs), and for this reason they potentially represent a promising cell population to apply for skeletal tissue regeneration applications. Here, we evaluate the effects of surface nanotopography on MPCs, considering the possibility that this specific physical stimulus alone can trigger MPC differentiation toward the mesenchymal lineage. In particular, we exploit nanogratings to deliver a mechanical, directional stimulus by contact interaction to promote cell morphological polarization and stretching. Following this interaction, we study the MPC-MSC transition by i. analyzing the change in cell morphotype by immunostaining of the key cell-adhesion structures and confocal fluorescence microscopy, and ii. quantifying the expression of cell-phenotype characterizing markers by flow cytometry. We demonstrate that the MPC mesengenic differentiation can be induced by the solely interaction with the NGs, in absence of any other external, chemical stimulus. This aspect is of particular interest in the case of multipotent progenitors as MPCs that, retaining both mesengenic and angiogenic potential, possess a high clinical appeal.

Billiary tract involvement in the course of disseminated histoplasmosis has been rarely reported. Here we present a severely immunosuppressed HIV-infected patient who presented with symptomatic acalculous cholecystitis caused by Histoplasma capsulatum.

The formation of fibroblastoid colonies by marrow cells in vitro has been used as a putative assay for a stem cell of haemopoietic stroma. Bone marrow from one patient with aplastic anaemia did not form any of these colonies, while its growth in diffusion chambers as an indirect measure of a haemopoietic stem cell was even better than normal. On the other hand, marrow from the other aplastic anaemia patient showed only quantitative decrease in the formation of fibroblastoid colonies and simultaneously grew very poorly in diffusion chambers. These patients were indistinguishable by the cytological examination of their marrow, however, the peripheral blood abnormalities were expressed less severely in the first patient. These results suggest the contribution of the defect in marrow cells, which form fibroblastoid colonies in vitro to the development of aplastic anaemia in these patients.

Bone marrow from 17 patients with refractory anaemia with excess of myeloblasts (RAEM) was cultured in methylcellulose semi-solid medium. Compared with normal bone marrow, 3 patterns of growth occurred corresponding with different clinical stages of the condition. Patients whose bone marrow grew normal colonies and those who produced a predominance of microclusters had the longest life expectancy, while those who produced a predominance of macroclusters had the shortest life expectancy with a high rate of acute leukaemic transformation. Colony culture appears to be a useful prognostic tool in this condition.

SummaryObjectivesBecause of the suboptimal recovery rate of brucellae from blood, it has been proposed that cultures of bone marrow, liver tissue, and lymph nodes may improve the recovery rate of the organism. Data in support of these recommendations are limited and not clearly convincing, especially that of bone marrow culture. The main purpose of this work was to evaluate the roles of blood, bone marrow, liver, and lymph node cultures in the diagnosis of human brucellosis.MethodsBlood and bone marrow cultures were evaluated in parallel in 103 cases of human brucellosis using Castaneda's biphasic technique. Simultaneous cultures of blood, bone marrow, liver, and lymph node aspirates were also carried out for 13 of these 103 cases.ResultsBlood culture identified 47 (45.6%) cases and bone marrow culture identified 85 (82.5%) cases. Faster recovery of Brucella spp was accomplished with the bone marrow culture (2.8±0.7 days, p

Identification of cytogenetic abnormalities plays an important role in the diagnosis and prognosis of leukemias. We report three cases of trisomy 6 as sole cytogenetic abnormality in acute myeloid leukemia (AML). Short-term unstimulated bone marrow culture showed two cases of AML-M1 and one case of AML-M2 with trisomy 6. It is known that trisomy 6 is a rare numerical abnormality and prognostic significance is not well established. More studies are required to assign the role of trisomy 6 in the development of leukemia as well as in prognosis.

Tissue inhibitors of metalloproteinases (TIMPs) はMatrix metalloproteinases (MMPs) に共通の内因性インヒビターであり, 細胞外マトリックス成分の分解を調節している。しかしTIMPsが, MMPsインヒビターとしての機能とは独立して, 広範囲の細胞に対し増殖活性を有することが明らかになっている。本研究では, TIMPsがPGE2などの破骨細胞形成促進因子共存下におけるマウス骨髄細胞培養系において, 破骨細胞の形成を促進することを明らかにした。すなわち, 培養液中に加えられるFCSよりTIMP-1およびTIMP-2を除くことにより破骨細胞形成が有意に抑制された。しかしリコンビナントTIMP-1およびTIMP-2を添加することにより破骨細胞形成は有意に回復した。さらに, 抗TIMP-1およびTIMP-2抗体を加えたところ, 破骨細胞形成が有意に抑制された。また, TIMPsの破骨細胞形成促進活性の作用機構を明らかにするため, メタロプロテアーゼインヒビターや合成MMPインヒビターをリコンビナントTIMPsの代りに添加したが, 破骨細胞形成の促進は認められなかった。本研究により, TIMP-1およびTIMP-2は破骨細胞形成をMMPs阻害作用とは異なる別の作用機構により促進していることが明らかとなった。

Evaluation of: Siba V, Horwood PF, Vanuga K et al. Evaluation of serological diagnostic tests for typhoid fever in Papua New Guinea using a composite reference standard. Clin. Vaccine Immunol. 19(11), 1833-1837 (2012). The study under review evaluated serological tests for typhoid fever against PCR as a reference test. While laboratory testing is essential for the confirmation of this severe disease, the low bacterial load and the low level of specific antibodies in the blood of typhoid patients combined with its acute character make interpretation of laboratory testing cumbersome. Validation of an index test requires good understanding of the diagnostic performance and assay characteristics of the reference test, and criteria and principles for study design and reporting outlined by the Quality Assessment of Diagnostic Accuracy Studies and the Standards for Reporting Studies of Diagnostic Accuracy should be followed. Described PCR assays for typhoid fever have not been validated against bone marrow culture, the gold standard, and their diagnostic utility remains to be established

Prolonged pre-transplant IFN administration in patients with chronic myeloid leukaemia has been associated with an increased risk of fatal transplant-related complications and an inferior outcome after allogeneic bone marrow transplantation. Using a two-stage long-term bone marrow culture as an in vitro model we were able to show a negative effect of higher doses of IFN pre-treatment of bone marrow stroma on haematopoesis. This correlated with a decline in the number of monocytes-macrophages. While monocytes-macrophages itself produce cytokines, a vicious circle may lead to an ineffective function of the microenvironment resulting in ineffective haematopoieses and increased transplant-related complications.

This study was conducted to evaluate the ability of the BacT/Alert automated blood culture system to detect Brucella spp. in comparison with traditional Brucella broth culture. Overall, 100 (50 bone marrow and 50 blood samples) paired cultures were obtained, and 59 were positive by at least one method. The Brucella broth culture method detected all 59 positive cultures (100%), and the BacT/Alert system detected 30 (50.8%) (P < 0.05). The mean detection times for B. melitensis were 4.5 days in the BacT/Alert system and 5 days in Brucella broth culture (P > 0.05). There is no significant difference between the two methods with respect to growth time of the microorganism, but Brucella broth culture is more sensitive than the BacT/Alert system.

We present a patient who has signs pointing to the involvement of lower motor neurons and myelofibrosis. To our knowledge, unlike lymphoproliferative disorders, co-occurrence of myelofibrosis and lower motor neuron disease (MND) has not been reported so far. A 64-year-old male patient was admitted to our hospital with the complaint of painful cramps in his neck and forearms. On physical examination marked hepatomegaly and splenomegaly were found. On neurologic examination nasal quality of the voice and slight palatal weakness were detected. There were generalised slight weakness and atrophy in both proximal and distal muscle groups. Fasciculations were observed especially in forearm muscles and it was observed that he had been avoiding head movements because of painful muscle cramps. Deep tendon reflexes were hypoactive. Nerve conduction studies were normal. By needle electromyography, giant motor unit action potentials (amplitudes up to 8 mV), fibrillation potentials, positive sharp waves and fasciculation potentials were detected in all muscles which were investigated. A hypercellular bone marrow (100%) was determined by bone marrow biopsy. In addition to increased production of the myeloid and megakaryocytic lines, abnormal aggregation and grouping of megakaryocytes were seen. Reticular fibers were increased. He had some benefit of dyphenilhydantoin treatment given for the painful clamps in his neck and forearm muscles. Hydroxyurea treatment was started for myelofibrosis. Six months later, his general condition was better, and the painful cramps were completely resolved. No marked deterioration has been detected in neurologic examination and electromyography for 1 year. (C) 2000 Elsevier Science B.V. All rights reserved.

Typhoid fever is a bacterial infection caused by Salmonella. The World Health Organization estimates the current incidence at 16–33 million cases annually. The incidence vastly decreased from its peak. Gastrointestinal symptoms of the disease include

The strong and long-lasting hematotoxic effect after benzene exposure in vivo (300 ppm, 6 hr/day, 5 days/week for 2 weeks) was assessed in mice with bone marrow cells grown in long-term bone marrow culture (LTBMC). Bone marrow cultures initiated 1 day after the last benzene exposure did not produce adequate numbers of hematopoietic cells over 3 weeks, and, in most cases, no erythroid or myeloid clonogenic cells could be recovered. The adherent cell layer of these cultures had a lowered capacity for supporting in vitro hematopoiesis after the second seeding with normal bone marrow cells compared with control cultures. Two weeks after the last benzene exposure, body weight, hematocrit, bone marrow cellularity, and committed hematopoietic progenitor content (BFU-E and CFU-GM) were regenerated to normal or subnormal values, whereas hematopoiesis in LTBMC was very poor. Over 8 weeks, little or no significant committed progenitor production was observed. Treatment of mice exposed to benzene with hemin (three doses of 3 micrograms/g bw i.v. over 2 weeks for a total dose of 9 micrograms/g) partially overcame the toxic effect of benzene on the hematopoietic system as measured by the LTBMC method. Cultures from mice treated with hemin had a modest recovery of BFU-E and CFU-GM clonogenic potential after 5 to 6 weeks in LTBMC. In contrast, little or no recovery was obtained for the adherent cell layer clonogenic capacity, even after hemin treatment. These results clearly indicate a strong, long-lasting toxic effect on the bone marrow stroma and a limited recovery of hematopoietic potential by clonogenic cells of the nonadherent population after in vivo hemin treatment.

Trilineage myelodysplasia (TMDS) in de novo acute myeloid leukemia (AML) at initial diagnosis and during remission has not been well recognized yet. In this review we describe the characteristics of de novo AML with TMDS (AML/TMDS) and with myelodysplastic remission marrow (AML/MRM) in view of the in vivo and in vitro disease progression. AML/TMDS was found in ten (10.4%) of 96 patients with de novo AML at initial diagnosis and AML/MRM were also observed in three (5.0%) out of 60 cases in remission after chemotherapy in our hospital between 1984 and 1992. Abnormal karyotypes were seen in six of nine AML/TMDS patients and all of the three AML/MRM. Karyotypic changes occurred in two of AML/TMDS and two of AML/MRM during their clinical course. Using the long term bone marrow culture (LTBMC) system that allowed abnormal clones to survive preferentially to the clone of normal karyotype, latent clones were detected in three patients with AML/TMDS and three of AML/MRM as in the cases of myelodysplastic syndrome (MDS) and AML transformed from MDS (MDS/AML) but not in the typical AML without myelodysplastic changes. Four of these cases exhibited the same karyotypes as seen during the clinical course. Primary abnormal karyotypes prior to clonal evolution were also observed in two of the AML/MRM. Taken together, both AML/TMDS and AML/MRM are similar to MDS/AML with respect to their myelodysplastic background and potential for disease progression and may have progressed to AML from the preceding disease status more rapidly than MDS/AML.

SUMMARY. There are no current U.K. or international guidelines or regulations covering the production, processing and storage of haemopoietic cells such as to allow their engraftment following myeloablative therapy. This paper seeks to provide such guidelines. It enumerates how quality control and assurance can be applied to this area of transfusion medicine; procedural steps relating to bone marrow harvest on peripheral blood stem cell collection are outlined and recommended doses of nucleated cells suggested for both procedures. General specifications for identification, storage and transportation of bone marrow and peripheral blood stem cells are included and specific laboratory procedures related to the provision of haemopoietic cells for engraftment are outlined. Umbilical cord blood transplants and long-term bone marrow culture are alluded to but these are still in a research phase.

A case of juvenile myelomonocytic leukaemia (JMML) associated with a chromosomal translocation (1;5) is described. Initial cytoreductive therapy failed to control the disease. In the absence of a matched family or unrelated donor, a Dexter-type long-term bone marrow culture (LTBMC) was established. The LTBMC showed preferential growth of normal stem cells over the abnormal clone, allowing a cultured autologous stem cell transplantation to be performed. Despite detection of the t(1;5) from 5 months to 7 years following cultured autograft, the patient remained in haematological remission. Currently the patient is alive and well at 10 years in full cytogenetic remission.

Summary. We previously established a long-term bone marrow culture (LTBMC) system in which novel abnormal karyotypes could emerge in vitro prior to the appearance of the same karyotypes in vivo in patients with myelodysplastic syndrome (MDS). We extended our study to examine whether acute myeloid leukaemia (AML) transformed from MDS (MDS/AML) and de novo AML with trilineage myelodysplasia (AML/TMDS) show clonal evolution in LTBMC similar to that of typical AML or MDS. We also analysed the cytogenetic changes in cultures with bone marrows from AML with myelodysplastic remission marrow (AML/MRM) as well as chronic myeloid leukaemia (CML) to compare them with typical AML with respect to the liability of clonal evolution. Among the 34 AML cases, abnormal karyotypes were newly detected in four of seven MDS/AML, three of six AML/TMDS and three of three AML/MRM. Novel abnormal karyotypes were also observed in nine out of 13 CML cases after culture. In contrast, no other abnormal karyotypes were found after culture in 18 typical AML without myelodysplasia. These findings suggest that AML/TMDS and AML/MRM are different from typical AML and are similar to MDS/AML and CML in view of their potential for disease progression from latent multiple clones. Typical AML may develop from a single abnormal clone without any subclones.

A simple, rapid, and easily reproducible method was developed for testing activity stimulating the growth of hemopoietic microenvironment in long-term bone marrow culture. It was found that in irradiated mice this activity is produced by bones.

Salmonella belong to the group of Enterobacteriaceae that are aerobic, gram-negative rods and approximately 1–3 μm × 0.5 μm in size [1, 2]. Currently there are approximately 2,400 pathogenic species of salmonella. Salmonella was first identified in 1880 by Eberth from the mesenteric nodes and spleen of a patient dying from typhoid fever [3, 4].

A method was devised to grow haemopoietic cells in long-term bone marrow culture (LTBMC) which requires only 1 x 10(6) cells/culture. Such miniature cultures were used to study growth patterns of marrow from patients with myelodysplastic syndromes (MDS). Consistent differences in LTBMC cellularity and cellular composition were noted between MDS and normal marrow. These differences were accentuated by rGM-CSF. The criteria which distinguished between and MDS marrows were: cell count at weeks 1 and 4, % neutrophils and % blasts. In 10 patients with unexplained macrocytosis or pancytopenia miniature LTBMC results clearly segregated into either 'normal' or 'MDS' growth patterns. Miniature LTBMC with rGM-CSF may therefore be a useful diagnostic test for early MDS.

The cryptic chromosomal abnormality, t(12;21)(p13;q22),is identified in about 20% of childhood B-cell acute lymphoblasticleukemia (B-ALL). The prevalence of the t(12;21) in one region inBrazil was determined in a sample of under 16-year-old ALLpatients by means of in situ hybridization using a fluorescentDNA probe specific for the TEL/AML1 rearrangement. Thisapproach gave a more accurate cytogenetic and clinical diagnosisof the subgroup of B-ALL patients, who, potentially, will benefitfrom more appropriate chemotherapy treatment. We selected 58bone marrow cytogenetic samples of newly diagnosed patientsaged between 6 months and 16 years old and with a B-ALLimmunophenotype (CD10 and/or CD19 positive). A chromosomalstudy was conducted after bone marrow culture and analysis byG-band. The same samples were evaluated by FISH to study thefused signals using two probes, one for the TEL and the other forthe AML1 gene marked with two different fluorochromes.Analysis was performed under a fluorescent microscope and theimages were captured using adequate filters and programs. Fromthe 58 samples, 11 were positive for the TEL/AML1 fusion(19%). Six positive samples presented with a normal karyotype.The most frequent cytogenetic alteration, in 25% of the cases,was hyperdiploidy (47-50 chromosomes). Deletion of the TELwild-type allele was observed in 27.3% of the cases. In two

Autologous hematopoietic stem cell transplantation (HSCT) has proved efficient to treat hematological malignancies. However, some patients fail to mobilize HSCs. It is known that the microenvironment may undergo damage after allogeneic HSCT. However little is known about how chemotherapy and growth factors contribute to this damage. We studied the stromal layer formation (SLF) and velocity before and after HSC mobilization, through long-term bone marrow culture from 22 patients and 10 healthy donors. Patients' SLF was similar at pre- (12/22) and post-mobilization (9/20), however for controls this occurred more at pre-mobilization (9/10; p=0.03). SLF velocity was higher at pre than post-mobilization in both groups. Leukemias and multiple myeloma showed faster growth of SLF than lymphomas at post-mobilization, the latter being similar to controls. These findings could be explained by less uncommitted HSC in controls than patients at post-mobilization. Control HSCs may migrate more in response to mobilization, resulting in a reduced population by those cells.

Human brucellosis is a multisystem disease that may notoriously mimic many other illnesses leading to misdiagnosis and increased morbidity. Six pediatric cases of brucellosis who had no epidemiologic evidence of the infection escaped early or correct recognition. The diagnosis of brucellosis was later made on the basis of significant brucella serology and positive blood or bone marrow culture. In endemic areas, a high index of suspicion should prevail in the evaluation of patients with vague or unexplained symptoms.

In chronic myeloid leukemia (CML) and acute myeloblastic leukemia (AML), experimental studies have shown growth advantage of the residual normal progenitor cells under long-term culture conditions. In some instances, this culture system has been used as a tool for purging bone marrow, before autotransplant. In this review, we discuss the efficiency of this technique, with respect to the persistence of sufficient numbers of normal stem and/or progenitor cells, capable of restoring hemopoiesis following pre-transplant conditioning regimens, and in relation to the elimination of leukemia cells, capable of causing relapse. Both issues are complex, and mostly still obscure. However if one considers the clinical outcome of patients receiving unpurged autografts, it is unlikely that long-term bone marrow cultures (LTBMCs) will be of substantial benefit in reducing leukemia relapse. Furthermore the clinical efficacy of this technique will in our opinion be difficult, if not impossible, to prove.

We obtained eight different cell lines in the long-term bone marrow culture system that showed a germ-line configuration of the joining (J) region segments of the Ig heavy-chain (IgH) genes. Their surface markers were CD45R+, Ly-1+, Lyb-2+, cIgM-, sIgM-, Ia-, Thy-1-, Mac-1-, and IL-2R (Tac)+. Use of very young mice and the presence of IL-5 were important for preferential promotion of the survival of B-lineage lymphocytes bearing the Ly-1 markers. When we treated two of them (J8 and J10) with 5-azacytidine for 24 h followed by co-culture with stromal cells and IL-.5, they became Ly-1+, sIgM+B cells, and Ly-1+, Mac-1+macrophagelike cells, respectively. After other early lymphoid lines (J1, J8, and J13) were maintained by co-culture with ST2 and IL-5 for more than a year, they showed a heterogeneous DNA rearrangement profile of the J region segment of the IgH gene, although only J13 rearranged theκ-light chain gene. Northern blot analysis revealed that these cell lines expressed Cμ-mRNA, andλ5-mRNA, consistent with normal pre-B cells. Intriguingly, J1, J8, and J13 expressed c-fmsmRNA constitutively. When J13 cells were co-cultured with ST2 and GM-CSF in place of ST2 and IL-5, they acquired Mac-1 expression and retained Ly-1 expression. They were morphologically macrophages, nonspecific-esterase-positive, and showed phagocytosis of latex beads. These results support evidence for a close relationship between the myeloid and Ly-1+B-cell pathways of differentiation, and indicate that our IL- 5-dependent clones are multipotential intermediates in differentiation from pro-B cells to B cells and macrophages.

To test the hypothesis that genistein stimulates the osteoblastic differentiation through the p38 mitogen activated protein kinase (MAPK)-core-binding factor 1 (Cbfa1) pathway.The activation of p38 MAPK was detected by Western blotting. Alkaline phosphatase (ALP) activity and calcium deposition were assessed for osteoblastic differentiation of bone marrow-derived mesenchymal stem cell (BMSC) cultures. The expression of Cbfa1 was analyzed at both the mRNA and protein levels. The activity of Cbfa1 was detected by electrophoretic mobility shift assay. Bone sialoprotein (BSP), ALP, osteocalcin (OC), and osteopontin (OPN) gene transcription were also evaluated by either RT-PCR or Northern blotting.Genistein (0.01-1 micromol/L) dose dependently led to the rapid and sustained activation of the p38 MAPK pathway in mouse BMSC cultures. Treatment with genistein (1 micromol/L) resulted in increased ALP activity and calcium deposition of BMSC cultures as a function of time. Genistein also enhanced Cbfa1 DNA binding activity and promoted the expressions of Cbfa1 itself as well as several Cbfa1-regulated genes, including ALP, BSP, OC, and OPN. Concurrent treatment with p38 MAPK inhibitor (SB203580) diminished the genistein-induced osteoblastic maturation and p38 MAPK-Cbfa1 activation in mouse BMSC cultures.These results indicated that genistein could stimulate the osteoblastic differentiation of BMSC cultures through the p38 MAPK-Cbfa1 pathway.

hydroxyapatite surface has led to a fuller understanding of this important cell. In this introductory chapter we set out the basic aspects of osteoclast origin and differentiation. Beginning with a description of the multinuclear cell found in bone and a brief introduction to its typing through functional characteristics, we discuss developing research from a historical viewpoint. However, attention will be focused on the current understanding of osteoclastogenesis, shown in Figure 1.2.

This in vitro study has been conducted to determine the optimal experimental conditions under which to produce canine neutrophils in long-term bone marrow cultures (LTBMC), establish functional parameters of neutrophils obtained from LTBMC and peripheral blood and to ascertain whether these cells display physiological similarities. Our aim is to provide an experimental model, enabling a correlation between hemopoietic injury and neutrophil functionality. The authors demonstrate for the first time that canine neutrophils grown in cultures are able to produce oxyradicals capable of killing bacterial products. Moreover, culture-grown neutrophils contain gelatinase granules, a marker of terminal neutrophil differentiation, and express a specific surface antigen. The results described in this article illustrate the development of a dynamic system that mimics physiological hemopoiesis.

Major advances in our understanding of human hematopoiesis have come from the development of semisolid in vitro culture techniques for the detection of progenitor cells capable of colony formation (see Chapter 28 , this volume). However, colony assays select for hematopoietic precursors committed to a specific lineage(s) and, therefore, are of limited value in the assessment of very early progenitor cells. Also, they do not provide a means of assessing the influence of microenvironmental cells deemed essential for maintaining hematopoiesis in vivo (1). Furthermore, for the assays to be valid, cells must be plated at a sufficiently low concentration to ensure clonality (a condition in which each colony has arisen from a single progenitor cell). Consequently, cell-cell interactions that may be important in exerting regulatory effects on hematopoiesis are likely to be minimal.

Here, we report a 72-year-old male patient with acute myeloid leukemia (AML) without maturation. Cytogenetic study of a bone marrow culture revealed the following karyotype: 47,XX,+21,+i(21)(q10)×2. Fluorescence in situ hybridization study with a locus specific probe for 21q22 verified a pentasomy of 21q as a sole clonal cytogenetic abnormality. To our knowledge, this is the first report of pentasomy 21q in AML without Down syndrome.

Bone marrow cells from patients with chronic myeloid leukemia (CML) in in vitro long-term bone marrow culture (LTBMC) show an impaired survival of Philadelphia (Ph) positive cells and, in a proportion of patients, the emergence of Philadelphia negative hemopoiesis. The standard conditions of in vitro cultures provide optimal purging effect. Selected patients can now have autologous bone marrow transplants (ABMT) with in vitro purged cells.

Background A retrospective examination of the utility of bone marrow sampling for identification of microorganisms was performed in an urban tertiary care hospital. Methods A retrospective review of culture and histology data from bone marrow specimens was performed for a 10-year period. Results Neither bone marrow culture nor special stains for microorganisms provided incremental benefit in identifying microbial agents compared with other methods such as blood culture. Conclusion Bone marrow aspiration/biopsy should only be performed selectively for diagnosis of an infectious etiology.

In a prospective study of typhoid fever in Ahmadu Bello University Hospital, Zaria, the relative diagnostic sensitivities of blood culture and bone marrow culture were studied. The results in 64 patients with proved diagnosis of typhoid fever (either by recovery of S. typhi from stool, blood and/or bone marrow or by a positive Widal agglutination test) are presented. Forty-four per cent and 59% of the patients yielded S. typhi on blood and bone marrow cultures, respectively. In 31 patients who were investigated by both blood and bone marrow cultures, the yields of S. typhi were 35% and 61% respectively. This difference is statistically significant ( P < 0.05). In this study bone marrow culture proved to be the most sensitive diagnostic test for typhoid fever. A simple technique of bone marrow aspiration is described and its use is recommended for large general teaching hospitals.

We report a case of acute monoblastic leukemia [French-American-British (FAB) M5a] observed in a 38-year-old man and associated at diagnosis with a t(5;10)(q13;q26) found in cells from a bone marrow culture. The patient survived only 2 months after diagnosis. t(5;10) as a solitary chromosome abnormality has not been previously reported in M5a, and, in the case that we describe, it appears to be correlated with a poor prognosis.

The impact of megakaryocyte growth in vitro on clinical data, especially outcome, was studied in 25 consecutive children with idiopathic thrombocytopenic purpura (ITP).Twenty children with untreated de novo ITP and five children with pretreated ITP were evaluated. The number of megakaryocyte colonies (cloning efficiency), the mean cell number per colony (mitotic amplification) and the percentages of polyploid megakaryocytes after 7 and 12 days in culture (relative size of the endomitotic compartment) were determined in two separate clonal assays. The culture data were related to clinical findings and outcome of the thrombocytopenia.The mean cell number per megakaryocyte colony was significantly correlated with the observed increase in the platelet count 5 days after starting therapy (n = 23; r = 0.642), and a significant negative correlation was found between the relative size of the endomitotic compartment and the duration of thrombocytopenia after bone marrow culture analysis (n = 25; r = -0.503). If all 25 children with ITP (untreated de novo and pretreated ITP) were considered, a normal frequency of polyploid megakaryocytes was associated with a duration of ITP for6 months in 14 of 16 cases, whereas an impaired polyploidization predicted a persistence of ITP for6 months in 9 of 9 cases (p0.0005); if only children with untreated de novo ITP (n = 20) were considered, 13 of 15 children with a normal polyploidization had an acute course of their ITP and 5 of 5 children with an impaired polyploidization developed chronic ITP (p0.003).The results in this small group of patients suggest that the assessment of the relative size of the endomitotic compartment after 7 and 12 days in plasma clot culture actually appears to be the best method for predicting a chronic course in children with ITP.