Processed umbilical cord blood (UCB) must be stored at cryogenic temperature at all times to maintain the quality and viability of the cells. However, a challenge is presented in the form of moving a large number of cryopreserved UCB samples to a new location. In this report, we share our experience on relocating more than 100,000 units of cryopreserved UCB samples stored in 12 liquid nitrogen freezers (LNFs) to our new laboratory.
Single-walled carbon nanotubes (SWCNTs) are carbon-based nanomaterials that possess immense industrial potential. Despite accumulating evidence that exposure to SWCNTs might be toxic to humans, our understanding of the mechanisms for cellular toxicity of SWCNTs remain limited. Here, we demonstrated that acute exposure of short (1-3μm) and regular-length (5-30μm) pristine, carboxylated or hydroxylated SWCNTs inhibited cell proliferation in human somatic and human stem cells in a cell type-dependent manner. The toxicity of regular-length pristine SWCNT was most evidenced in NP69>CYT00086>MCF-10A>MRC-5>HaCaT > HEK-293T>HepG2. In contrast, the short pristine SWCNTs were relatively less toxic in most of the cells being tested, except for NP69 which is more sensitive to short pristine SWCNTs as compared to regular-length pristine SWCNTs. Interestingly, carboxylation and hydroxylation of regular-length SWCNTs, but not the short SWCNTs, significantly reduced the cytotoxicity. Exposure of SWCNTs also induced caspase 3 and 9 activities, mitochondrial membrane depolarization, and significant apoptosis and necrosis in MRC-5 embryonic lung fibroblasts. In contrast, SWCNTs inhibited the proliferation of HaCaT human keratinocytes without inducing cell death. Further analyses by gene expression profiling and Connectivity Map analysis showed that SWCNTs induced a gene expression signature characteristic of heat shock protein 90 (HSP90) inhibition in MRC-5 cells, suggesting that SWCNTs may inhibit the HSP90 signaling pathway. Indeed, exposure of MRC-5 cells to SWCNTs results in a dose-dependent decrease in HSP90 client proteins (AKT, CDK4 and BCL2) and a concomitant increase in HSP70 expression. In addition, SWCNTs also significantly inhibited HSP90-dependent protein refolding. Finally, we showed that ectopic expression of HSP90, but not HSP40 or HSP70, completely abrogated the cytotoxic effects of SWCNTs, suggesting that SWCNT-induced cellular toxicity is HSP90 dependent. In summary, our findings suggest that the toxic effects of SWCNTs are mediated through inhibition of HSP90 in human lung fibroblasts and keratinocytes.
Mesenchymal stromal cells (MSC) are an attractive cell-targeting vehicle for gene delivery. MIDGE (an acronym for Minimalistic, Immunologically Defined Gene Expression) construct is relatively safer than the viral or plasmid expression system as the detrimental eukaryotic and prokaryotic gene and sequences have been eliminated. The objective of this study was to test the ability of the human MSC (hMSC) to deliver the erythropoietin (EPO) gene in a nude mice model following nucleofection using a MIDGE construct. hMSC nucleofected with MIDGE encoding the EPO gene was injected subcutaneously in Matrigel at the dorsal flank of nude mice. Subcutaneous implantation of nucleofected hMSC resulted in increased hemoglobin level with presence of human EPO in the peripheral blood of the injected nude mice in the first two weeks post-implantation compared with the control groups. The basal layer of the hair shaft in the dermal layer was found to be significantly positive for immunohistochemical staining of a human EPO antibody. However, only a few basal layers of the hair shaft were found to be positively stained for CD105. In conclusion, hMSC harboring MIDGE-EPO could deliver and transiently express the EPO gene in the nude mice model. These cells could be localized to the hair follicle and secreted EPO protein might have possible role in hair regeneration.
Activation of immunoregulatory T lymphocyte subsets has been observed in dengue viral infection, being more evident in dengue hemorrhagic fever (DHF) than in classical dengue fever (DF). There are, however, as yet no well-defined host markers to determine which patients with dengue viral infection will develop severe complications during the acute febrile stage of the disease. A study was performed to compare the cellular immune status in DHF, DF and non-dengue viral infections (NDF) in order to determine the value of these parameters in distinguishing DHF from classic DF and other viral infections during the acute febrile stage of the disease. This study involved 109 febrile patients admitted because of suspected DHF. Fifty patients were serologically confirmed cases of dengue infection, of which 25 had grade 1 or 2 DHF. There was a reduction in total T (CD3), CD4 and CD8 cells in DHF and demonstrated that a low level of CD3, CD4, CD8 and CD5 cells discriminated DHF from DF patients during the febrile stage of the illness. In contrast, B (CD19) cells and natural killer (NK) cells did not appear to be discriminatory in this study. Receiver operating characteristic (ROC) curve analysis showed that a combination of CD3 cell of < or = 45% and CD5 cell of < or = 55% was the best marker to identify DHF patients (sensitivity = 84% and specificity = 52% for CD3 cell of < or = 45%; sensitivity = 92% and specificity = 71% for CD5 cell of < or = 55%). CD4 cell of < or = 25% and CD8 cell < or = 30% were equally good in discriminating DHF from DF patients. On the other hand, the ROC curves indicated no clear difference between the immunoregulatory cell counts in DF from NDF Lymphopenia, atypical lymphocytosis and thrombocytopenia were significantly more evident in dengue compared to non-dengue infection but did not appear to be discriminatory among DHF and DF patients. The reduction in CD3, CD4, CD8, CD5 cells correlated with the degree of thrombocytopenia in DHF (p < 0.05) which suggests that these cells probably participate in a common pathogenetic mechanism.
Neonatal screening for G6PD deficiency has long been established in many countries. The aim of the study was to determine whether the routine semiquantitative fluorescent spot test could detect all cases of G6PD deficiency, including those cases with partial deficiency (residual red cell G6PD activity between 20-60% of normal). We compared the results of G6PD screening by the semiquantitative fluorescent spot test and quantitative G6PD activity assay on a group of 976 neonates and 67 known female heterozygotes. The values for mean G6PD activity of G6PD-normal neonates and 293 healthy adult females were determined. There was no significant difference in the mean normal G6PD activity between the two racial groups in the neonates (669 Malays, 307 Chinese) and in the 293 healthy adult females (150 Malays, 143 Chinese) group. The values for the upper limits of total deficiency (20% of normal residual activity) for neonates and adult females were 2.92 U/gHb and 1.54 U/gHb, respectively. The upper limits of partial deficiency (60% of normal residual activity) were 8.7 U/gHb and 4.6 U/gHb respectively. The prevalence of G6PD deficiency among the male neonates was 5.1% (26) by both the fluorescent spot test and the enzyme assay method. The G6PD activity levels of all 26 cases of G6PD-deficient male neonates were < 20% normal (severe enzyme deficiency). In the female neonate group, the frequency of G6PD deficiency was 1.3% (6 of 472) by the fluorescent spot test and 9.35% (44 of 472) by enzyme assay. The 6 cases diagnosed as deficient by the fluorescent spot test showed severe enzyme deficiency (< 2.92 U/gHb). The remaining 38 female neonates had partial enzyme deficiency and all were misdiagnosed as normal by the fluorescent spot test. In the female heterozygote group, G6PD deficiency was diagnosed in 53% (35 of 67) by enzyme assay and in 7.5% (4 of 67) of cases by the fluorescent spot test. The 4 cases detected by fluorescent spot test had severe enzyme deficiency (<1.6 U/gHb). The remaining 31 (46.3%) cases, diagnosed as normal by fluorescent spot test, showed partial G6PD deficiency. In conclusion, we found that the semiquantitative fluorescent spot test could only diagnose cases of total G6PD deficiency and misclassified the partially-deficient cases as normal. In this study, the overall prevalence of G6PD deficiency was 3.28% by the semiquantitative fluorescent spot test and 7.17% by enzyme assay. This means that 3.9% of G6PD-deficient neonates were missed by the routine fluorescent spot test and they were found to be exclusively females. This study demonstrates a need to use a method that can correctly classify female heterozygotes with partial G6PD deficiency. The clinical implication is that these individuals may be at risk of the hemolytic complication of G6PD deficiency.
We describe a patient with multiple myeloma, who initially responded to chemotherapy and went into remission. She presented 10 months later with a right breast lump which was confirmed by core biopsy to be a plasmacytoma. Further treatment with radiotherapy, thalidomide and later second line chemotherapy appeared unsuccessful and she showed rapid disease progression with rising paraproteins and new extramedullary plasmacytoma lesions in the forehead, supraclavicular region, nasopharynx, liver, spleen, pancreas and paraaortic lymph nodes.
Hodgkin's disease (HD) in association with pregnancy is rarely reported. Thus, the data in the management of pregnancy complicated by HD is limited. We report here the management of advanced HD in pregnancy that was treated successfully with chemotherapy.
Haemophagocytic syndrome (HPS) should be included in the differential diagnosis of pyrexia of unknown origin (PUO). The hallmark of HPS is the accumulation of activated macrophages that engulf haematopoietic cells in the reticuloendothelial system. We describe a patient with unexplained fever in which a final diagnosis of HPS was established in a bone marrow study.
Aplastic anemia is a relatively uncommon disease and conventional management options include immunosuppressive drugs and/or haematopoeitic stem cell transplantation. It is now known that the pathogenesis of aplastic anemia is immune mediated. Mycophenolate mofetil is a common immunosuppressive drug now used mainly in prophylaxis of graft rejection in organ transplant and also for prevention/treatment for graft versus host disease in haemtopoeitic stem cell transplantation. It is thought that mycophenolate mofetil may be useful in this group of patients. In this short report, mycophenolate mofetil was tried in 6 patients who had severe aplastic anemia with variable doses for a minimum duration of 9 months. The result has however not been encouraging.
Patients (particularly elderly) undergoing evaluation for peripheral neuropathy of unknown cause should be screened for the presence of a monoclonal protein (M protein). The association of a neuropathy and a paraproteinaemia such as Waldenstrom's Macroglobulinaemia (WM) is not uncommon with the former antedating the haematologic symptoms by several years. Response to treatment has varied from good to very poor. We describe a case of WM presenting as a subacute demyelinating peripheral neuropathy. There was prompt resolution of the neuropathy with intravenous immunoglobulin therapy. Subsequent treatment with cyclophosphamide and plasmapheresis resulted in complete clinical remission with no further neurological relapses.
The presence of serum cold agglutinin can be the initial presentation of lymphoproliferative diseases. Conditions with persistent cold agglutinins are a spectrum of diseases that vary from benign lymphoproliferation of the "autoimmune-like chronic cold agglutinin disease" to malignant lymphoma. We report a case of a 72-year-old woman who presented with severe anaemia, hepatosplenomegaly and episodes of peripheral haemagglutination precipitated by cold exposure. The haemoglobin was 5.6 g/dL with a cold agglutinin titer of 1:256 at 4 degrees C and 1:8 at room temperature (30 degrees C). The cold agglutinin showed anti-I specificity and kappa light chain restriction. Peripheral blood showed atypical lymphoid cells with a B-cell immunophenotype. Immunoglobulin gene rearrangement study by polymerase chain reaction (PCR) showed an amplified band at 100 bp, consistent with a clonal proliferation of B-lymphocytes. We believe that our patient had cold antibody haemolytic anaemia as the initial presentation of a low-grade non-Hodgkin's lymphoma. The association of cold antibody haemolytic anaemia with low-grade B-cell lymphoma is unusual.
A 49 year-old Indian housewife was diagnosed with Hodgkin's disease in 1995. She was given combination chemotherapy comprising Chlorambucil, Vincristine, Procarbazine and Prednisolone. Unfortunately she defaulted after two courses of chemotherapy. One year later, she developed progressive right knee swelling and pain, associated with loss of appetite, loss of weight, intermittent fever, night sweats and pruritus. The right knee swelling measured 15 cm x 20 cm and was warm and tender. A plain radiograph of the right knee revealed osteolytic lesions at the distal end of the right femur and the proximal ends of the right tibia and fibula, associated with gross periosteal reaction and soft tissue swelling. Apart from left cervical lymphoadenopathy, examination of other systems was unremarkable. Pelvic bone marrow biopsy was inconclusive. An open biopsy of the lower end of the right femur was consistent with Hodgkin's disease. She was given salvage combination therapy comprising Chlorambucil, Vincristine, Procarbazine, Prednisolone, Doxorubicin, Bleomycin and Vinblastine. She tolerated the treatment well and responded with significant reduction in the swelling and pain of the right knee. Unfortunately, she again defaulted treatment after 2 courses of chemotherapy. This case illustrates an unusual presentation of Hodgkin's disease in relapse.
Acute leukaemia may rarely present as diffuse papules, nodules and plaques forming leonine facies. Leukaemia cutis generally carries a poor prognosis, and responds less well to chemotherapy. We described a case of acute myelomonocytic leukaemia presenting as leonine facies as a result of extensive cutaneous infiltration. The patient did not achieve haematological remission following standard induction chemotherapy and succumbed 6 weeks after the diagnosis was made.
A fulminant clinical presentation with high fever and hepatosplenomegaly, together with a course of worsening pancytopenia, coagulopathy and liver failure, is suggestive of the haem syndrome (HPS). Bone marrow examination is diagnostic. We present 3 cases of HPS associated with different aetiologies including acute Ebstein Barr virus infection, T cell lymphoma, and malignant histiocytosis. In all the cases, the diagnosis was made late and the patients succumbed before definitive therapy could be administered.
The effect of L-asparaginase on the thyroid gland has not been well documented. We report the first two cases of hyperthyroidism associated with thyroid nodule following L-asparaginase therapy for acute lymphoblastic leukemia (ALL). The thyroid function abnormalities were not severe, short-lived and did not require specific therapy.
A 27-year-old Indian woman at 23 weeks' gestation presented with decompensated liver cirrhosis, coagulopathy, restrictive lung disease with cor pulmonale and preeclampsia. She was diagnosed to have sea-blue histiocyte syndrome (SBHS) at the age of 13 years and was treated conservatively. There was worsening liver, respiratory and bone marrow function as the pregnancy progressed. She underwent a successful pregnancy despite her poor medical condition and advanced disease state. We described the first case of familial SBHS in a pregnant patient from Asia.
A 56-year-old Chinese lady with valvular heart disease and atrial fibrillation was referred to us from a private hospital for further management of autoimmune haemolytic anaemia. Physical examination and laboratory investigations did not support the diagnosis of haemolytic anaemia. However, direct antiglobulin test (DAT) was strongly positive with anti-IgG and negative with anti-C3d. There was also mild anaemia and reticulocytosis, which was attributable to persistent haematuria. The DAT became positive after commencing Unasyn and cessation was associated with decreasing reactivity of the positive DAT. We believe that the positive DAT in this patient was most likely due to the Unasyn therapy.
A six year old Chinese boy with relapsed Acute Promyelocytic Leukaemia (APML) failed to respond to reinduction with Daunorubicin and Cytarabine infusion. He was successfully treated with all trans-Retinoic Acid (45 mg/m2/day) orally. After four weeks of treatment, he was in complete remission. The side effects of all trans-Retinoic Acid were negligible.