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ABSTRACTThe antimicrobial activities of chloroquine (CQ) and several 4-aminoquinoline drugs were tested against Penicillium marneffei, an opportunistic fungus that invades and grows inside macrophages and causes disseminated infection in AIDS patients. Human THP1 and mouse J774 macrophages were infected in vitro with P. marneffeiconidia and treated with different doses of drugs for 24 to 48 h followed by cell lysis and the counting of P. marneffeiCFU. CQ and amodiaquine exerted a dose-dependent inhibition of fungal growth, whereas quinine and artemisinin were fungistatic and not fungicidal. The antifungal activity of CQ was not due to an impairment of fungal iron acquisition in that it was not reversed by the addition of iron nitrilotriacetate, FeCl3, or iron ammonium citrate. Perl's staining indicated that CQ did not alter the ability of J774 cells to acquire iron from the medium. Most likely, CQ's antifungal activity is due to an increase in the intravacuolar pH and a disruption of pH-dependent metabolic processes. Indeed, we demonstrate that (i) bafilomycin A1 and ammonium chloride, two agents known to alkalinize intracellular vesicles by different mechanisms, were inhibitory as well and (ii) a newly synthesized 4-amino-7-chloroquinoline molecule (compound 9), lacking the terminal amino side chain of CQ that assists in drug accumulation, did not inhibit P. marneffeigrowth. These results suggest that CQ has a potential for use in prophylaxis of P. marneffeiinfections in human immunodeficiency virus-infected patients in countries where P. marneffeiis endemic.

We report that hematopoietic progenitor cells expressing the CD34 antigen (CD34+ cells) transiently circulate in the peripheral blood (PB) of cancer patients treated with 7 g/m2 cyclophosphamide (HD-CTX) with or without recombinant human granulocyte macrophage-colony stimulating factor (rHuGM-CSF). In adult humans, CD34+ cells represent a minor fraction (1% to 4%) of bone marrow (BM) cells, comprising virtually all hematopoietic colony-forming progenitors in vitro and probably also stem cells capable of restoring hematopoiesis of lethally irradiated hosts. We show that CD34+ cell circulation is fivefold enhanced by rHuGM-CSF 5.5 protein micrograms/kg/day by continuous intravenous infusion for 14 days after HD-CTX. During the third week after HD-CTX (ie, when CD34+ cells peak in the circulation), large- scale collection of PB leukocytes by three to four continuous-flow leukaphereses allows the yield of 2.19 to 2.73 x 10(9) or 0.45 to 0.56 x 10(9) CD34+ cells depending on whether or not patients receive rHuGM- CSF. The number of CD34+ cells retrieved from the circulation by leukaphereses exceeds the number that can be harvested by multiple BM aspirations under general anesthesia. Thus, after therapy with HD-CTX and rHuGM-CSF, PB represents a rich source of hematopoietic progenitors possibly usable for restoring hematopoiesis after myeloablative chemoradiotherapy. To determine whether CD34+ cells found in the PB are equivalent to their marrow counterpart, we evaluated their in vitro growth characteristics and immunological phenotype by colony assays and dual-color immunofluorescence, respectively. We show that PB CD34+ cells possess qualitatively normal hematopoietic colony growth and high cloning efficiency comparable to that observed with BM CD34+ cells. In addition, PB CD34+ cells display heterogeneous surface membrane differentiation antigens analogous to BM CD34+ cells. The availability of large quantities of CD34+ cells by leukapheresis is relevant to the field of stem cell transplantation and possibly to genetic manipulations of the hematopoietic system in humans.

Optimum methods of harvesting circulating hematopoietic progenitors for autologous transplantation to support myeloablative cancer therapy are still uncertain, mostly because of the lack of an assay for marrow- repopulating stem cells. The CFU-GM assay, the commonly used indirect indicator of the quality of the graft, is poorly standardized and provides results evaluable only retrospectively. Based on the knowledge that hematopoietic progenitors express CD34 and CD33 differentiation antigens, we developed a dual-color direct immunofluorescence flow cytometry assay with the aim of replacing the CFU-GM assay advantageously. For this purpose, we applied both assays to 157 blood samples obtained daily throughout 20 different recoveries from pancytopenia induced by high-dose cyclophosphamide or etoposide cancer therapy with or without recombinant human GM colony-stimulating factor (rhGM-CSF). The appearance of CD34+ cells in the circulation indicated that hematopoietic progenitors had increased to more than 500 CFU- GM/mL, a level clinically adequate for large-scale harvest by leukapheresis. Total CD34+ cells correlated well with CFU-GM (r = .89), and data could be fitted by a linear regression line described by the equation y = 388.3 + 64.0x, where y = CFU-GM/mL and x = CD34+ cells per microliter. Moreover, in a series of six patients treated with myeloablative chemoradiotherapy, early hematopoietic recovery of marrow functions was predicted more accurately by the number of transplanted CD34+/CD33+ cells than by either total nucleated cells, CFU-GM, CD34+/CD33- cells, or CD34-/CD33+ cells. Data presented in this article favor clinical use of the CD34/CD33 flow cytometry assay to guide harvesting of circulating hematopoietic progenitors for autologous transplantation and contribute to better understanding of the role played by circulating hematopoietic progenitor cell subsets in marrow recovery after myeloablative cancer therapy.

The mapping near Kras2 of pulmonary adenoma susceptibility 1 (Pas1), a major locus affecting inherited predisposition to lung cancer in mice prompted us to test the homologous human region (12p12) for association with lung adenocarcinoma, by a population-based study. We genotyped 213 lung adenocarcinoma patients and 219 healthy blood donor subjects for five polymorphic markers mapping in the putative region of interest. Three marker polymorphisms, located in a region spanning approximately 700 kb, were significantly associated with lung adenocarcinoma risk. Furthermore, polymorphisms in KRAS2 and PTHLH loci were also associated with tumor prognosis. These results suggest the existence of a human Pas1 homologous locus on chromosome 12p12.

Kurz and Salvadori's Theory of Production thoroughly accounts for the recent developments in the classical theory of value and distribution. The authors, however, claim that long-period classical analysis can only deal with stationary economies, or economies in balanced growth, and restrict their theoretical treatment accordingly. This aspect of the book is singled out for comments, and it is argued that Kurz and Salvadori's perception of the limits to the use of the 'long-period method' in classical analysis does not seem to rely on convincing foundations. Some critical remarks are also offered concerning the 'alternative analytical framework' suggested in the book.

Seventy-seven (68 operable breast cancer with > 9 metastatic axillary nodes and 9 inflammatory breast cancer) entered this study. During hematopoietic recovery after cancer therapy with highdose cyclophosphamide (7 g/m2; HD-CTX) circulating hematopoietic progenitors were collected by leukapheresis (LK) in all patients and then cryopreserved for autologous transplantation. Following HD-CTX, 70 patients were treated with hematopoietic growth factor(s) for 14 days: 38 with rhGM-CSF (group a), 16 with rhlL-3 (group b), 11 with sequential rhlL-3 and rhGM-CSF (group c), 5 with sequential rhlL-3 and rhG-CSF (group d). Seven control patients (group e) did not receive any growth factor.Leukaphereses, carried out over 2-4 consecutive days per patient, were started earlier in group c and in group d patients (mean day: +12 after HD-CTX). The sequential administration of rhIL-3 and rhG-CSF (group d) resulted in clearly higher yield of CFU-GM and CD34+ cells per leukapheresis (65.9x104/Kg versus 20.9x106/Kg, respectively) if compared with other groups of treatment.

The Autors summarise their experience with the new “early granulocyte transfusion” scheme obtained in cancer patients. The data, based on three trials, clearly point out 1) the importance of early granulocyte transfusion as compared to the traditional one; 2) the efficacy of early granulocyte transfusion in pediatric age and among adult patients in those with good regenerating hemopoietic system.

After myeloablative regimens, combined reinfusion of peripheral blood hematopoietic circulating progenitor cells (CPC) and bone marrow, yields a very rapid hematopoietic recovery. Therefore, based on the knowledge that CPC express the CD34 and CD33 differentiation antigen, we have developed a direct immunofluorescence flow cytometry assay to detect the peak of CPC in the peripheral blood of patients treated with high dose chemotherapy and growth factors. This assay, compared to CFU-GM assay, has the following advantages: 1) easy to do 2) standardized method 3) real time information on CPC number. This work illustrates the practical aspects of this assay and substantiate the widespread use of the CD34/33 flow cytometry assay to guide harvesting of circulating hematopoietic progenitors for autologous transplantation.