Defined nuclear changes accompany the reprogramming of the microspore to embryogenesis

The switch of the gametophytic developmental program toward pollen embryogenesis to form a haploid plant represents an important alternative for plant breeding. In the present study, the switch of the gametophytic developmental program toward a sporophytic pathway, "embryogenesis," has been studied in three different plant species, Brassica, tobacco, and pepper. The switch has been induced by stress (heat shock) at the very responsive stage of the microspore, which is the vacuolate period. As a result, the cell nucleus undergoes striking structural changes with regard to late gametophytic development, including alterations of biosynthetic activities and proliferative activity. An enrichment in HSP70 heat-shock protein and in the presence of Ntf6-MAP kinase was observed after inductive treatment in the nuclei during early embryogenesis. This apparently reflected the possible roles of these proteins, specifically the protective role of HSP70 for the nuclear machinery, and signal transduction of Ntf6-MAPK for the entry of cells into proliferation. Importantly, the observed nuclear changes were similar in the three species investigated and represented convenient markers for early monitoring of embryogenesis and selection purposes for obtaining double-haploid plants in plant breeding.

Influence of the formulation on the in vitro transdermal penetration of sodium diclofenac. Evaluation of the topical and systemic anti-inflammatory activity in the rat

A study on the transdermal permeation through human skin was performed with a series of 6 semisolid formulations (A-F) containing 1% sodium diclofenac (CAS 15307-79-6) (w/w). A commercially available drug preparation was tested as a reference. Based on permeation characteristics, a study on the topical and systemic anti-inflammatory activities of three formulations (A, F and the reference formulation) was conducted using the model of erythema induced by UV radiation in hairless rats. This is expected, together with the index of topical anti-inflammatory activity to allow the selection of the most suitable formulation for dermal application. The following representative parameters were measured in the permeation study: amount of diclofenac permeated at 24 h, flow, lag time and amount of drug retained in skin at 24 h. Of the formulations tested, diclofenac formulated in the reference formulation showed the highest values of amount of diclofenac permeated at 24 h, amount of drug retained in skin at 24 and flow. As regards the skin inflammation test, no significant differences (p < 0.05) are seen between the topical and systemic anti-inflammatory activities of the three formulations tested. However, in absolute value, formulation F shows a lower systemic activity, which would prevent potential side effects of diclofenac. Since the topical anti-inflammatory index obtained for this formulation was > 1, it is concluded that a good therapeutic performance could be obtained in the treatment of local inflammation with diclofenac by using formulation F.

Galactomannans from the cell walls of species of Paecilomyces sect. Paecilomyces and their teleomorphs as immunotaxonomic markers

An alkali-extractable and water-soluble fraction (F1S) was obtained from cell walls of Paecilomyces variotii and species of the related genera Talaromyces, Byssochlamys and Thermoascus. The structure of the main polysaccharide of these fractions was studied and found to consist of a core of (1 --> 6)-alpha-mannopyranose partially substituted at 0.2 by chains of galactofuranose and shorter chains of mannopyranose. The differences in the regularity of the branching points and the length of the galactofuranose side chains are useful to distinguish between species. These differences were detected by immunological methods, since highly specific polyclonal antibodies were raised against these polysaccharides. Mycelium of P. variotii CBS 990.73A was stained by indirect immunofluorescence. The polysaccharides studied in this work differ from the one described for species from section Isarioidea, and this is another indication of the heterogeneity of the genus Paecilomyces.

Absolute bioavailability and absorption profile of cyanamide in man

A pharmacokinetic study of cyanamide, an inhibitor of aldehyde dehydrogenase (EC1.2.1.3) used as an adjuvant in the aversive therapy of chronic alcoholism, has been carried out in healthy male volunteers following intravenous and oral administration. Cyanamide plasma levels were determined by a sensitive HPLC assay, specific for cyanamide. After intravenous administration cyanamide displayed a disposition profile according to a two-compartmental open model. Elimination half-life and total plasma clearance values ranged from 42.2 to 61.3 min and from 0.0123 to 0.0190 L.kg-1.min-1, respectively. After oral administration of 0.3, 1.0, and 1.5 mg/kg x +/- SEM values of Cmax, tmax (median) and AUC were 0.18 +/- 0.03, 0.91 +/- 0.11, and 1.65 +/- 0.27 micrograms.ml-1; 13.5, 13.5, and 12 min; and 8.59 +/- 1.32, 45.39 +/- 1.62, and 77.86 +/- 17.49 micrograms.ml-1.min, respectively. Absorption was not complete and the oral bioavailability, 45.55 +/- 9.22, 70.12 +/- 4.73, and 80.78 +/- 8.19% for the 0.3, 1.0, and 1.5 mg/kg doses, respectively, increased with the dose administered. The models that consider a first-order absorption process alone (whether with a fixed or variable bioavailability value as a function of dose) or with loss of drug due to presystemic metabolism (with zero-order or Michaelis-Menten kinetics) were simultaneously fitted to plasma level data obtained following 1 mg/kg i.v. and 0.3, 1.0, and 1.5 mg/kg oral administrations. The model that best fit the data was that with a first-order absorption process plus a loss by presystemic metabolism with Michaelis-Menten kinetics, suggesting the presence of a saturable first-pass effect.

A rapid single-laser flow cytometric method for discrimination of early apoptotic cells in a heterogenous cell population

A recently reported cytometric method described the possibility of discriminating apoptotic from necrotic cells using FITC-labelled annexin V and propidium iodide (PI). Nevertheless, the brightness of PI-staining and its extensive spectral emission overlap with phycoerythrin (PE) does not permit the study of a subset of a heterogenous cell population with single laser instrumentation. The surface staining of a subset with PE in a heterogenous cell population therefore requires another exclusion dye to detect necrotic cells. We used 7-amino-actinomycin D (7-AAD) that can be excited by the 488 nm argon laser line. 7-AAD emits in the far red range of the spectrum and 7-AAD spectral emission can be separated from the emissions of FITC and PE. The fluorescence parameters allow characterization of necrotic (7-AAD+ annexin V-FITC+ cells), apoptotic (7-AAD-annexin V-FITC+ cells) and viable cells (7-AAD- annexin V-FITC- cells) in a subset of PE+ cells. The value of this method was demonstrated by measuring apoptosis and necrosis in a model of HL-60 cells exposed to different inducers of cell death. The method was validated by fluorescent cell sorting in combination with morphologic examination of the sorted cells. The technique we present is particularly valuable in a clinical setting because it enables rapid multiparameter analysis of necrosis and early apoptosis in combination with cell surface phenotyping with a single laser. We present the effects of haemopoietic growth factor deprivation on myeloid progenitor CD34+ cells as an example of its application.

Reproducible scoring of CFU-GM and BFU-E grown in collagen-based semisolid medium after a short (3 h) training

Colony counting remains an important source of variation in colony-forming unit-granulocyte-macrophage (CFU-GM) assays performed in methylcellulose or agar. We studied the reliability of colony scoring of CFU-GM assays carried out with collagen, a matrix that allows gel collection on glass slides and in situ cellular morphology. Fourteen slides were exchanged among laboratories, and two rounds of colony (CFU-GM and burst-forming units-erythrocyte [BFU-E]) counting were performed by 11 (first counting), then 8 (second counting) different laboratories, the majority of which had no previous experience of collagen gel cultures and reading. Two-way analysis of variance (ANOVA) of the first round of colony counting showed significant differences among centers in CFU-GM counts (p = 0.023) but not in BFU-E counts (p = 0.163). Coefficients of variation for the 14 slides ranged from 22% to 50% (median 28%) for CFU-GM counts and from 12% to 74% (median 23%) for BFU-E counts. After a 3 h session of collective colony reading attended by members of 8 laboratories, a second round of colony counting was performed. This time, ANOVA showed no significant difference among centers for CFU-GM (p = 0.533) and BFU-E (p = 0.328) counts, and coefficients of variation were significantly improved, with medians of 17% for CFU-GM counts and 20% for BFU-E counts. In addition, when data from the second round of readings were analyzed without the 2 centers counting consistently low (center 8) or consistently high (center 5), variance among centers was further improved for both CFU-GM (p = 0.798) and BFU-E (p = 0.619). In summary, this study shows for the first time that reproducible BFU-E and CFU-GM scoring can be achieved using collagen-based semisolid medium (now commercially available) as long as adequate training in colony identification is provided.

All-trans-retinoic acid up-regulates CD38 but not c-Kit antigens on human marrow CD34+ cells without recruitment into cell cycle

Retinoids, especially all-trans-retinoic acid (ATRA), are well known for their differentiating activity on HL-60 cells. Moreover ATRA induces CD38 antigen overexpression on these cells. In this study we examined the effects of ATRA on purified normal CD34+ cells from adult human marrows incubated with ATRA (1 microM) or stem cell factor (SCF) after 7 d liquid cultures in serum-deprived medium. Before and after the incubation, CD34+ cells were studied by flow cytometry to evaluate the cell-surface expression of CD38 and c-Kit antigens and the cycle status of these cells using high-resolution analysis (DNA content v Ki-67 antigen expression) to clarify the functional meaning of antigenic variations. When compared with control cultures, ATRA-treated cells displayed changes in their immunophenotypic profile. Particularly relevant was the up-regulation of CD38 antigen with a mean (+/-SEM) fold increase of 21 +/- 0.1 (P=0.028) for geometric mean fluorescence intensity (GMFI), without modulation of c-Kit expression. SCF only down-regulated expression of c-Kit with a fold decrease of 4.6 +/- 0.9 for GMFI (P=0.043). Unlike SCF, ATRA did not induce CD34+ cells to entry into cell cycle despite increased levels of surface CD38 antigen. Moreover morphological and functional assays did not argue for an ATRA-induced maturation process. Contrary to steady-state cells, CD34+ cells treated with pharmacological doses of ATRA alone displayed CD38 over-expression without change in c-Kit levels and cycle status, suggesting an absence of maturation pressure.

Cytokines released in vitro by stromal cells from autologous bone marrow transplant patients with lymphoid malignancy

Marrow stromal cells of patients treated by autologous bone marrow transplantation (ABMT) for malignancies have been assessed for their ability to secrete granulocyte colony-stimulating factor (G-CSF), granulocyte-macrophage colony-stimulating factor (GM-CSF), stem cell factor (SCF), leukemia inhibitory factor (LIF), interleukin-6 (IL-6), transforming growth factor beta1 (TGFbeta1) and macrophage inflammatory protein-1alpha. (MIP-1alpha). Long-term marrow cultures were established from 10 patients prior to and 3 months after ABMT, from 7 patients 1 yr after ABMT and from 11 controls. Cytokines in culture supernatants of stromal layers (SL) were evaluated by enzyme-linked immunosorbent assay (ELISA). Significant differences between patient groups and controls were apparent in baseline production of GM-CSF, SCF, MIP-1alpha and TGFbeta1. After IL-1beta addition in cultures, G-CSF production was reduced in pretransplant and post-transplant patients compared to controls. The production of TGFbeta1, LIF, IL-6 and more particularly SCF were reduced in post-transplant patients, while elevated levels of GM-CSF and MIP-1alpha were observed in these patients only when the values were corrected for the number of cells growing in the SL. These results indicate a prolonged stromal defect in growth factor production following ABMT for the early-stage acting cytokines IL-6, LIF and SCF as well as for G-CSF, but not for GM-CSF, while the production of the 2 inhibitors shows different pathways.

In vitro effect of stem cell factor on human clonogenic marrow progenitors after myeloablative treatments

Abnormal hematopoiesis, including a deficiency of marrow progenitors and particularly of erythroid progenitors, has been described after autologous stem cell transplantation (ASCT), persisting for several years. In order to explain this deficiency, a resistance of marrow progenitors to stem cell factor (SCF) after ASCT was investigated. Marrow samples were harvested from pregraft patients at graft collection prior to ASCT, transplanted patients 6-24 months after high-dose therapy and control patients. CD34+ cells were cultured in a serum-free clonogenic assay with increasing doses of SCF. The clonogenic efficiency without SCF was lower for BFU-E in treated groups than in controls, whereas it was not different for CFU-GM. With increasing doses of SCF a dose-dependent effect was found on the numbers of both CFU-GM and BFU-E in all groups, although the maximal number of BFU-E remained lower in treated groups. However, the SCF dose that induced 50% of maximal BFU-E growth (D50) was similar in all groups. Furthermore, a dose-dependent effect on the size of BFU-E was found in all groups, with no difference in the proportion of large colonies. Thus, clonogenic erythroid progenitors from patients who have received myelotoxic treatments remain sensitive to SCF, with no evidence for a chemotherapy-related resistance.

Vaccination against contagious bovine pleuropneumonia and the use of molecular tools in epidemiology

Contagious bovine pleuropneumonia is a serious threat to cattle not only in Africa but also in southern Europe and possibly Asia. It is now present in countries that had been free of the disease for many years, giving rise to doubts about the efficiency of the control strategies. In Africa CBPP is controlled mainly by a vaccination policy that uses variant strains of Mycoplasma mycoides subsp mycoides biotype SC, called T1/44 or T1sr. Until recently, it was not possible to differentiate the various strains within the biotype and consequently to identify the vaccine strains. Restriction analysis of mycoplasma DNA with HindIII and Pst1 has been applied to 24 strains of African origin and one European strain. Each enzyme gave rise to different restriction profiles and the combination of the results permitted subdivision of these strains into 9 groups. Interestingly, some profiles of pathogenic strains seem to be restricted to certain geographical areas. The profile of the poorly immunogenic vaccinal strain KH3J is also very peculiar, and it is easily distinguished from that of the other vaccine strains originating from T1. This technique is simple once the strains are isolated. Efforts are now under way to use molecular tools based on PCR products to alleviate the difficulty of isolation.

Changes in the functional capacity of marrow stromal cells after autologous bone marrow transplantation

Marrow stromal cells were evaluated several months after autologous BMT for their capacity to support both normal hemopoiesis and secrete the main growth factors involved in its control, G-CSF, GM-CSF, IL-3 and SCF. Stromal layers (SL) were obtained by long-term marrow cultures (LTMC) established from 15 patients (9 with hematologic malignancies and 6 with solid tumors) 3 months after autologous BMT and were compared to pre-graft patients. After irradiation, both post-graft and pre-graft SL were recharged with the same inoculum of normal marrow cells. As compared to pre-graft values, CFU-GM production on post-graft SL was significantly increased during the first 2 weeks of culture whereas it was decreased from week 3 to week 8. These findings were only observed in patients with hematologic malignancies and not in patients with solid tumors. Growth factor secretion was evaluated by ELISA in the supernatants of unstimulated and IL-1-stimulated SL from 10 post-graft patients, 13 pre-graft patients and 5 normal controls. In any group of patients, IL-3 was undetectable either spontaneously or after IL-1-stimulation. As compared to controls, secretion by IL-1-stimulated SL was not different for GM-CSF in pre- and post-graft patients but tended to be decreased for G-CSF in post-graft patients. SCF secretion, which was not induced by IL-1, appeared dramatically decreased in both pre- and post-graft patients. The capacity of post-graft SL to support CFU-GM growth in LTMC was correlated at week 1 with G-CSF secretion and from week 3 to week 8 with SCF secretion. These results suggest that microenvironment remains qualitatively damaged several months after BMT involving a decreased capacity both to support early hemopoiesis and to secrete SCF, particularly in patients grafted for hemopoietic malignancies.

Morgagni's hernia resolved by laparoscopic surgery

Morgagni's hernias represent between 2 and 4% of the whole of nontraumatic diaphragmatic hernias in the adult, and the treatment (even with minimal symptoms) is always with surgery. We present the case of a 50-year-old woman with an oppressive, postprandial discomfort in the right side of her thorax and with increased pain when supine. The x-ray examination indicated a large portion of transverse colon inside the thoracic cavity. Once the diagnosis of Morgagni's hernia had been obtained, she was scheduled for laparoscopic surgery to reduce the hernia and to reconstruct the defect of the diaphragm using a polypropylene mesh.

Influence of d-limonene on the transdermal penetration of felodipine

Felodipine is a calcium antagonist, one of the dihydropyridines, with potential application in transdermal therapeutic systems (TTS). Earlier studies reported that the high lag time of this drug limited its potential development in a TTS. The present study analyzes the effect of d-limonene at concentrations of 0.5, 1, 5 and 10% on the transdermal penetration of this drug. The study was performed using a diffusion technique in vitro, with the skin of the hairless rat. d-Limonene significantly reduced the lag time (Tl) to 1.4 h at a concentration of 1% (compared with 9.8 h in its absence). Higher concentrations did not produce a significant decrease in the value of this parameter. The presence of d-limonene in the formulae produces an increase in the permeability constant (Kp) and the flux (J). The relation between this increase and the percentage of d-limonene was non-linear. An asymptotic value was obtained at a concentration of 5%, with increases of 993% and 1570% for Kp and J, respectively.

Structure of complex cell wall polysaccharides isolated from Trichoderma and Hypocrea species

The structure of fungal polysaccharides isolated from the cell wall of Trichoderma reesei, T. koningii, and Hypocrea psychrophila, have been investigated by means of chemical analyses and 1D and 2D NMR spectroscopy. The polysaccharides have an irregular structure, idealized as follows: [formula: see text] The proportions of the different side chains vary from a species to another, being n above some three times larger in H. psychrophila than in T. reesei or T. koningii.

Influence of formulation on the in vitro transdermal penetration of flutrimazole

Flutrimazole (1-[(2-fluorophenyl)(4-fluorophenyl)phenylmethyl]-1 H-imidazole, CAS 119006-77-8, UR-4056) is a new wide spectrum local imidazolic antifungal agent that has already been formulated as a dermal cream (FDC). A comparative study was carried out of the release of flutrimazole from two emulsions in which the drug has been incorporated differently: one dissolved in the oily phase (E24) and the other dispersed in the aqueous formulation phase (E25). Based on the E25 formulation, two more dermal creams were prepared, E27 with benzyl alcohol and E28 with diazolidinyl urea as preservative agents. A comparative study of transdermal penetration including E27, E28, FDC (reference 1% flutrimazole dermal cream) and 1% flutrimazole hydroalcoholic solution was also performed. An amount of the sample dosage form containing 10 mg of flutrimazole was applied to a Franz type cell. The penetration membrane used was cellulose acetate in the release studies and human skin provided by a plastic surgery clinic in the transdermal penetration study. The amount released after 7 h was 36.3 +/- 4.9 micrograms when flutrimazole was dissolved (E24) and 35.9 +/- 5.3 micrograms when flutrimazole was dispersed (E25). Although the differences were not significant, the cream with dispersed flutrimazole was selected for further penetration studies due to its better stability observed in previous studies. The amounts of drug penetrated after 44 h were 31.3, 41.5, 38.3 and 186.5 micrograms for E27, E28, FDC dermal creams and topical hydroalcoholic solution, respectively. The solution showed a statistically significant difference (p < 0.05) from the other formulations, however, no differences were observed between the dermal cream formulations. No differences were neither obtained between the different dermal creams when the amount of drug retained in the skin was compared. This allows to assert that the excipients used do not have different influences on transdermal penetration. In all cases, the mean quantity penetrated in relation to the dose applied was at most 0.5%. These results allow to infer that flutrimazole shows scarce transdermal penetration. Further, the amount of flutrimazole retained per gram of skin is more than 100 times the MIC per gram obtained in previous in vitro studies. It may be assumed that the topical application of the new formulations assayed would allow to obtain a good therapeutic response.

Structure-absorption relationships of a series of 6-fluoroquinolones

The physicochemical constants and some structural parameters (topological, steric, and electronic) of eight third-generation monofluorate quinolones (six uncommercialized and two used clinically [ciprofloxacin and enrofloxacin]) were determined: pKa, intrinsic solubility (S0), chromatographic capacity factor, partition coefficient (P), valency molecular connectivity, molecular volume, molecular surface area, dipolar moment, and charges associated with each atom of the molecule. The apparent intestinal absorption rate constants (K(abs)) in rat (in vivo perfusion) and the MICs at which 90% of the isolates are inhibited (MIC90s) against 100 Escherichia coli strains were also determined. We sought to establish simple nonlinear and multiple linear correlations between K(abs), on the one hand, and lipophilic parameters and other physicochemical and structural parameters estimated. Of the nonlinear functions examined, the hyperbolic had the best correlation between K(abs) and P, which was in accordance with the Wagner-Sedman (J. G. Wagner and A. J. Sedman, J. Pharmacokinet. Biopharm. 1:23-50, 1973) equation, whereas, after application of the stepwise multiple linear regression method, a multiple linear correlation with some predictive value could be established only between K(abs) as a dependent variable and log P and log S0 as independent variables. In conclusion, the K(abs) and MIC90 of the quinolone CNV 8902 suggest that it is a sufficiently interesting compound to warrant the investigation of its potential therapeutic use orally.

Structural elucidation of acidic fungal polysaccharides isolated from the cell-wall of genera Cylindrocladium and Calonectria

The structure of acidic fungal polysaccharides, isolated from the cell wall of Cylindrocladium and Calonectria species, has been investigated by chemical analysis, methylation and reductive cleavage analyses, and 1D and 2D 1H and 13C NMR spectroscopy. The polysaccharides have an idealized repeating unit: [formula: see text] linked to a small mannan core (< 5%), with n = 3 for Cylindrocladium penicilloides and C. quinqueseptatum and n = 5 for Calonectria theae, C. crotalariae, and C. colhounii.

A comparative study of the transdermal penetration of a series of nonsteroidal antiinflammatory drugs

The transdermal absorption of a series of nonsteroidal antiinflammatory drugs (NSAIDs): indomethacin, ketoprofen, diclofenac, piroxicam, tenoxicam, ketorolac, and aceclofenac) was studied in vitro with human skin. The purpose of the study was to determine the permeation parameters (permeability rate constant, Kp; lag time, TL, and flux, J) as measures of the intrinsic transdermal permeabilities of these drugs to predict their potential for formulation in a transdermal therapeutic system (TTS). A linear correlation was established between the intrinsic log Kp values and the intrinsic partition coefficients (r = 0.863, p = 0.012, n = 7). Diclofenac had the highest value of in vitro transdermal penetration at approximately 0% ionization (Kp = 3.5 cm/h) and ketoprofen had the highest flux (J = 16 micrograms/h.cm2) of the NSAIDs assayed. Ketorolac would provide the plasma concentrations at steady state that would be nearest to the therapeutic concentration (Cr/Css = 26). Also, considering the whole permeation profile in vitro, ketorolac would be the most suitable candidate of the series studied to be formulated as a TTS.

The mechanisms involved in the impairment of hematopoiesis after autologous bone marrow transplantation

Hematopoiesis after autologous bone marrow transplantation (BMT) is characterized by a prolonged and severe deficiency of marrow progenitors for several years, especially of erythroid and megakaryocyte progenitors, while the peripheral blood cells and marrow cellularity have reached relatively normal values within a few weeks. These anomalies are comparable to those reported for allogeneic BMT, despite the absence of any allo-immune reaction or post-graft immunosuppressive therapy. Post-graft hematopoietic impairment is the consequence of quantitative and qualitative changes involving both stem cell and stromal compartments which are expressed by an impaired capacity of stem cell self-renewal and commitment towards erythroid and megakaryocytic lineages. Besides the toxicity of conditioning regimens, hematopoietic reconstitution using autologous grafts is particularly dependent on a combination of factors related to the patient, such as underlying disease and pre-graft chemotherapy regimens, and to the graft processing itself, such as in vitro purging with chemotherapeutic agents.

An antigenic water-soluble glucogalactomannan extracted from cell walls of Paecilomyces fumosoroseus and Paecilomyces farinosus

The water-soluble fraction (F1S) obtained after solubilizing in alkali the cell walls of four strains of Paecilomyces fumosoroseus and two of Paecilomyces farinosus amounted to 8.3-14.5% of the dry cell wall material. Two polysaccharides, F1S-A (13-20%) and F1S-B (57-68%) were separated from F1S by gel permeation through Sepharose CL-6B. 1H and 13C NMR spectra of F1S-B were recorded and showed analogous structural features in the six isolates of the two species. The fractions isolated from P. fumosoroseus strain CBS 375.70 were subjected to structural analysis and shown to be a (1-->4)-alpha-glucan (F1S-A) and a branched (1-->6)-mannan with terminal residues of beta-galactopyranose (F1S-B). Polyclonal antibodies against the latter polysaccharide were obtained (titre 1/8000). These antibodies reacted specifically with the F1S-B polysaccharides obtained from the four strains of P. fumosoroseus and the two strains of P. farinosus, but they did not react with similar fractions from other species of the same or related genera. The antibodies specifically stained P. fumosoroseus hyphae in indirect immunofluorescence tests.

Manifestation and epidemiology of contagious bovine pleuropneumonia in Africa

Contagious bovine pleuropneumonia (CBPP) is one of the major threats to cattle health and production in Africa. This article reviews the clinical manifestations, lesions and epidemiology of the disease. The clinical manifestations and lesions are typical and are no different in Africa from those seen in other countries. CBPP is a respiratory disease characterised by pneumonia and serofibrinous pleurisy. The usual form of this disease is acute but chronic forms are frequent, particularly in endemic regions. Hyperacute forms, with a high mortality rate, can be seen at the beginning of outbreaks in newly infected regions. The epidemiology of the disease in Africa is dominated by four factors, namely: cattle are the only species affected, there is no reservoir in wild animals, clinical cases or chronic carriers are the usual sources of infection, through direct contact, and cattle movements play a very important role in the maintenance and extension of the disease. CBPP is widespread in Africa and, according to the Office International des Epizooties and to various reports in 1995, the disease is present in 24 countries of tropical Africa. In western Africa, CBPP is mainly enzootic or sporadic but in some countries the incidence is increasing. The situation in Central Africa is not very alarming. However, in eastern and south-eastern Africa, CBPP has become a major issue, placing southern Africa under direct threat. An evaluation of economic losses due to the disease and the cost-benefit ratio of control programmes is indispensable, since such economic assessments are needed before policy-makers decide on programmes of control or eradication. This is an area which needs to be addressed immediately, as the launching of new campaigns, particularly in eastern and southern Africa, is urgently needed.

Granulocyte-macrophage colony-stimulating factor accelerates hematopoietic recovery after autologous bone marrow or peripheral blood progenitor cell transplantation and high-dose chemotherapy for lymphoma

The use of recombinant human granulocyte-macrophage colony-stimulating factor (rhGM-CSF) as an adjunct to autologous bone marrow transplantation (ABMT) or peripheral blood progenitor cell (PBPC) transplantation was evaluated in 59 lymphoma patients. Patients were divided into three groups. In group I (n = 21) patients received rhGM-CSF (5 micrograms/kg daily) at the time of PBPC collection and during the recovery phase post-infusion. In group II (n = 12) patients received rhGM-CSF as an adjunct to ABMT. In group III (n = 26) they were grafted with bone marrow without rhGM-CSF. Administration of rhGM-CSF (groups I and II) significantly reduced the time to myeloid engraftment, the number of febrile days and the median duration of antibiotics administration and of hospital stay when compared with the group in which patients did not receive rhGM-CSF. The only difference between ABMT and PBPC, given with rhGM-CSF support, was observed in the duration of hospitalization (group I > group II, P < 0.05). These data show that rhGM-CSF is highly effective in reducing the duration of aplasia following BMT and PBPC transfusion, and there appears to be little difference in efficacy between these techniques, provided that patients also receive rhGM-CSF.

Distal tibial triplane fractures: long-term follow-up

The cases of 35 patients in whom a triplane fracture had been treated at the Ramón y Cajal Hospital were reviewed. The diagnosis of biplane and triplane fracture can now be made by standard radiograph. However, plain radiographs alone did not accurately demonstrate the configuration of the fracture, and computed tomography must be performed. Closed reduction should be attempted first. Failure to obtain or maintain (or both) an adequate closed reduction is an indication for operative treatment. Prognosis is surprisingly good. Only when adequate reduction (< 2 mm displacement) has not been achieved can degenerative changes be seen at long-term follow-up (> 5 years).

Long-term cultures to evaluate engraftment potential of CD34+ cells from peripheral blood after mobilization by chemotherapy with and without GM-CSF

In this study we used a long-term culture system to evaluate engraftment potential of human peripheral blood (PB) cells mobilized by chemotherapy (CT) associated or not with granulocyte-macrophage colony-stimulating factor (GM-CSF). In six patients who underwent blood cell transplantation, PB CD34+ cells were cultured after mobilization and were compared to CD34+ cells in steady state from PB and bone marrow (BM). Qualitative differences were shown between PBC samples obtained after CT with and without GM-CSF. Despite similar CFU-GM counts at culture initiation, GM-CSF-mobilized CD34+ cells might contain a lower proportion of primitive stem cells, as suggested by the significant decrease in CFU-GM numbers produced beyond week 5 compared to CT-mobilized CD34+ cells (p = 0.033). Likewise, the percentage of CFU-GM produced beyond week 5 in relation to initial input was significantly lower than steady-state PB (p = 0.039) and than CT-mobilized CD34+ cells (p = 0.033). However, this CFU-GM production with GM-CSF-mobilized PB CD34+ cells was not different from cultures with BMC CD34+ cells. These results suggest that GM-CSF can mobilize CFU-GM in the blood mainly by differentiation at the expense of the primitive stem cell compartment. It appears valuable to define clearly for each mobilizing procedure a particular threshold of CFU-GM which reflects sufficient numbers of primitive stem cells to ensure long-term engraftment.

Electrocardiographic diagnosis of the responsible coronary artery in acute inferior myocardial infarction through right chest leads V3R-V8R. A prospective study

In order to identify the electrocardiographic changes that occur in right-chest leads V3R-V8R for the most significant diagnosis of the responsible coronary artery of acute myocardial infarction, the authors performed a prospective study on 66 patients in whom coronary arteriography was done between the first and twelfth weeks after suffering the infarction. Electrocardiograms were done within the first six hours after the onset of symptoms. Lesions of the right coronary artery were found in 46 patients--27 at a proximal level and 19 at a distal one--and in 20 patients the circumflex coronary artery was injured. The electrocardiographic findings were studied in 2 groups of leads: V3R-V4R and V5R-V8R. An ST elevation equal to or higher than 0.5 mm and the presence of Q waves in V3R-V4R are specific markers of lesions of the right coronary artery (P < 0.001). Lowering of the ST segment in V3R-V4R is a specific marker of a circumflex artery lesion (P < 0.001). An ST elevation equal to or higher than 1 mm in V3R-V4R is specific for a proximal lesion of the right coronary artery (P < 0.001). No specific marker for a lesion of the distal right coronary artery was identified, its more significant characteristic being an "isoelectrical" ST segment (between 0 and 0.4 mm), an rS morphology and positive T waves in V3R-V4R.

Protection of goats against rinderpest by vaccination with attenuated peste des petits ruminants virus

The ability of the attenuated peste des petits ruminants vaccine virus to protect small ruminants against virulent rinderpest virus was investigated. Out of four susceptible goats that were infected with the highly virulent Saudi strain of rinderpest virus by intranasal ioculation, three developed mild clinical signs of disease and infected susceptible in-contact goats and cattle with rinderpest virus. However, four goats which had been vaccinated with the attenuated peste des petits ruminants virus resisted challenge with virulent rinderpest virus and did not infect susceptible in-contact animals.

Overview and epidemiology of contagious bovine pleuropneumonia in Africa

Contagious bovine pleuropneumonia (CBPP) is widespread in Africa and in other regions of the world. This disease is particularly important in the semi-arid, sub-humid and arid zones of tropical Africa, but CBPP incidence seems to be increasing in some parts of East Africa. The epidemiology of CBPP is characterised by the occurrence of sub-acute and symptomless infections, and the persistence of chronic carriers. Spread of the disease is associated with cattle movement. The major obstacles to eradication of CBPP are the difficulties in controlling cattle movement and applying quarantine and slaughter policies. Other difficulties arise due to the absence of a field test for diagnosis, the relatively short duration of post-vaccinal immunity and the lack of data on the economic impact of the disease. The Pan-African Rinderpest Campaign strategy for CBPP control and eradication conforms with national control programmes, which include cost/benefit analysis. It is planned to perform blanket vaccination against the disease for three to five years, depending on the economic situation of each country. Stringent control of cattle movement will complement vaccination campaigns. The eradication phase, including slaughter measures, will be instituted following reduction of CBPP incidence. Regional and international coordination will be instituted to control international cattle movement and harmonise control strategies.

Prolonged impairment of hematopoiesis after high-dose therapy followed by autologous bone marrow transplantation

Hematopoietic reconstitution has been studied in 180 patients after autologous bone marrow transplantation based on peripheral blood cell (PBC) recovery time and marrow progenitor counts sequentially tested for up to 4 years. Several factors that could influence hematopoietic reconstitution have been analyzed including sex, age, diagnosis, disease status, conditioning regimen, graft progenitor content, graft in vitro purging, and postgrafting administration of growth factors. Before transplantation, marrow progenitor values were normal only for colony-forming unit granulocyte macrophage (CFU-GM) in contrast to colony-forming unit-erythroid (CFU-E), burst-forming unit-erythroid (BFU-E), and colony-forming unit-megakaryocyte (CFU-Meg). After transplantation, as described with allogenic grafts, these values remained low for several years, although PBC counts were nearly normalized within a few weeks. Pregraft values were reached after 2 years for CFU-GM and BFU-E, and after 4 years for CFU-E, while CFU-Meg failed to reach pregraft values after this time. Normal levels were reached after 4 years only by CFU-GM. On univariate and multivariate analysis, the following factors appeared to delay both PBC and marrow progenitor reconstitution: underlying disease (particularly acute myeloid leukemias), graft characteristics such as low stem cell content and in vitro purging, conditioning regimens with total body irradiation or busulfan, and lack of postgraft administration of growth factors. In conclusion, high-dose therapy followed by bone marrow transplantation induces a deep and prolonged impairment of hematopoiesis irrespective of any alloimmune reaction or postgraft immunosuppressive therapy.(ABSTRACT TRUNCATED AT 250 WORDS)

Cytokine production in long-term marrow cultures after autologous bone marrow transplantation

We compared the release of granulocyte-macrophage colony-stimulating factor (GM-CSF), granulocyte colony-stimulating factor (G-CSF) and tumor necrosis factor alpha (TNF alpha) in the supernatant of long-term bone marrow cultures (LTBMC) derived from 10 control patients and from 14 patients before and 3 months after autologous bone marrow transplantation (BMT). The three cytokines were spontaneously present in the supernatant of cultures established from patients before and after autologous BMT, while GM-CSF remained undetectable in the supernatants of control patients. The maximal levels of cytokines were produced after the first week and were not statistically different between control, patients before and after grafts although the granulocyte-macrophage colony-forming unit (CFU-GM) production in long-term culture (LTC) was lower in patients after graft compared with control patients (median values at LTC initiation: 32 and 158, respectively, P < 0.001 and median values of the total production: 510 and 12406, respectively, P < 0.002). However, GM-CSF was more frequently detected in patients after graft than in control patients. This study demonstrated that the production of GM-CSF, G-CSF and TNF alpha is not impaired in patients after graft (medians 0, 870.5, 173.5 pg/ml and ranges 0-31.2, 0-10 000 and 0-1426, respectively) compared with control patients (medians 0, 69, 66 pg/ml and ranges 0, 0-13 280 and 0-1318, respectively), although patients after graft were shown to have lower marrow CFU-GM counts. These results suggest that the ability of the accessory cells to produce these cytokines was not reduced after autologous BMT.

Haemopoiesis of transplanted patients with autologous marrows assessed by long-term marrow culture

We assessed the effect of antitumoural therapy at intensive doses on the haemopoietic system using long-term marrow cultures (LTMC) established from 33 patients (25 with haematological diseases and eight with solid tumours) after autologous bone marrow transplantation (ABMT). When compared to 42 pre-graft patients, a decreased CFU-GM production and a defect in stromal layer (SL) confluence were found after ABMT on day 90 but also on day 365. However, these abnormalities were observed only in patients with haematological diseases and no differences between pre-graft and post-graft results were found in patients with solid tumours. Among the patients with haematological diseases, on day 90 those with acute lymphoid leukaemias showed lower CFU-GM production whereas patients with non-Hodgkin's lymphomas developed more frequently subconfluent or confluent SL. Other factors studied such as sex, patient age, disease status, marrow purging and post-graft administration of growth factors did not appear to influence post-graft LTMC results. Multivariate analysis including all the patients has shown (a) that solid tumours were associated with higher CFU-GM production, and (b) that conditioning regimens with total body irradiation (TBI) or busulfan led more frequently to non-confluent SL. In conclusion, high-dose therapy followed by ABMT can induce a persistent impairment of the stem cell and stromal cell compartments, particularly in patients with haematological diseases conditioned with TBI, despite the absence of any alloimmune reaction and post-graft immunosuppressive therapy.

[Epidemiologic study of bluetongue in sheep, cattle and different species of wild animals in the Ivory Coast]

Between 1992 and 1993, a serological survey was conducted in Côte d'Ivoire on 623 sera from sheep, 215 sera from cattle and 211 sera from wild herbivores. These sera were tested for bluetongue virus (BTV) antibodies using an agar gel immunodiffusion test. The purpose of this survey was twofold: to establish the incidence of bluetongue in the country, and to analyse the putative role of BTV in the reproductive pathology of sheep. Seroprevalence was 52 +/- 4% in sheep, 95 +/- 3% in cattle, and 56 +/- 7% in wild herbivores. The authors found antibodies against BTV in kob (Kobus kob Erxleben, 1777), common waterbuck (Kobus ellipsiprymnus Ogilby, 1833), roan antelope (Hippotragus equinus Desmarest, 1804), buffalo (Syncerus caffer Sparrman, 1779), hartebeest (Alcelaphus buselaphus Pallas, 1766) and elephant (Loxodonta africana Blumenbach, 1797). A significant difference was found in seroprevalence in sheep between the three areas covered by the survey. Antibody prevalence increased significantly with age in sheep and wild herbivores, and seroprevalence was higher in dams with a history of abortion. It can therefore be concluded that bluetongue is enzootic in Côte d'Ivoire.

A comparative in vitro study of transdermal absorption of antiemetics

Transdermal absorption of a series of antiemetics (alizapride, bromopride, clebopride, domperidone, metoclopramide, metopimazine, and scopolamine) was studied in vitro with the skin of hairless rats as the membrane. The aim of the study was to determine the permeation parameters [transdermal permeability rate constant (Kp), lag time, and flux] as a measure of the intrinsic permeability of these drugs across the skin, with a view to predicting their potential therapeutic formulation in Transdermal Therapeutic Systems. A linear correlation was established between the log Kp values corresponding to the antiemetics studied and their melting point (r = 0.8120, p < 0.05). The logarithm of Kp for the antiemetics studied can be predicted from the logarithm of the intrinsic partition coefficient (n-octanol-water) by a parabolic function (r = 0.9284, p < 0.01). Bromopride showed the shortest lag time (19.73 h), whereas clebopride was the most suitable drug as a candidate for formulation in transdermal delivery systems.

Sensitivity of human CFU-GM to mafosfamide: analysis of the factors affecting individual variations

A study of CFU-GM sensitivity to mafosfamide was carried out in 67 candidates for ABMT. A lethal dose 95 (LD95) was calculated from the dose-response curve. Despite standardized treatment conditions of marrow buffy-coat cells, LD95 values that were normally distributed (median 100 micrograms/ml; mean +/- SEM 95.6 +/- 4.0 micrograms/ml) varied considerably from patient to patient (range 30-160 micrograms/ml). Three independent factors appeared to confer greater sensitivity of CFU-GM: low patient age, low CFU-GM rate in treated cells and prolonged delay of CFU-GM sensitivity test from last chemotherapy course. In contrast, sex, pathology, disease status, number of previous chemotherapies and use of CY before the test did not influence CFU-GM sensitivity. Forty-six patients were autografted with mafosfamide-treated marrows according to their LD95. The mean percentage of CFU-GM effectively recovered after graft purging was 3.96 +/- 2.09%. All patients engrafted well and their peripheral blood cell recoveries were correlated with graft CFU-GM content evaluated before purging but not after purging or after freezing. In multivariate analysis, this parameter remained the only factor predicting hematopoietic recovery among other patient variables such as sex, age, pathology, disease status, previous chemotherapies or TBI in conditioning regimens. In a subgroup of 39 patients with lymphoid malignancies compared with 25 patients autografted for non-Hodgkin's lymphomas with unpurged marrows, the delay in days (medians) was similar for leukocytes > 1 x 10(9)/l (19 vs 17 days) and for neutrophils > 0.5 x 10(9)/l (18 vs 17 days) while it was longer for platelets > 50 x 10(9)/l (34 vs 128 days).(ABSTRACT TRUNCATED AT 250 WORDS)

[Nervous syndrome in sheep on the Ivory Coast. I. Epidemiological and clinical study, methods of diagnosis and treatment]

The ovine nervous syndrome in Côte-d'Ivoire is similar to the cerebrocortical necrosis (CCN) due to vitamin B1 deficiency. All classical symptoms of CCN were observed (locomotor ataxia with subsequent paralysis) and histological evidence for polioencephalomalacia was given. However, the circumstances for occurrence of the disease are very different in the two cases, i.e. CCN is a disease encountered in young fattening ruminants in developed countries while the ovine nervous syndrome is mainly observed in Côte-d'Ivoire during the dry season when pastures become sparse and dry and when the feed supply is insufficient. Thus, the main cause, which is rather univocal, is a sudden decrease in the nutritive value of the diet, but the accurate etiopathogenesis of the disease has not yet been determined. In a flock where 10-30% of the animals are ill, the mortality may reach 80-90%. No classical biochemical assays were specific enough to establish a precise diagnosis of the nervous syndrome. However, it should be pointed out that the CK (creatinine kinase) values very regularly rose and that the ASAT (aspartate aminotransferase) values were high in 75% of the cases. In the present African field conditions, the precise diagnosis is based on the efficiency of the vitamin B1 treatment and, for the dead animals, on the histological analysis of the brain.

Gastric, intestinal and colonic absorption of a series of beta-blockers in the rat

Gastric, intestinal and colonic absorption rates of a series of eleven beta-blockers (alprenolol hydrochloride, atenolol, bunolol hydrochloride, penbutolol sulphate, pronethalol hydrochloride, metoprolol, oxprenolol, bevantolol, bufuralol, propranolol hydrochloride and timolol maleate) were estimated using Doluisio's method. The gastric absorption rate was very low and the absorption rate constant could not be assessed accurately in all cases. In the small intestine, the absorption rate constants, Ka, at pH 6.2 ranged between 0.38 h-1 for atenolol and 4.28 h-1 for penbutolol. In the colon, the rate of drug absorption at pH 7.5 ranged between 0.12 h-1 for atenolol and 2.15 h-1 for penbutolol. In most cases, colonic absorption rate constants were of the same order as those obtained in the small intestine, demonstrating the good penetrability through colonic membrane of the series studied. The relationship between absorption rate constants found in the small intestine and colon and the partition constant ([1/Rf]-1), was studied for this non-homologous series of beta-blocker drugs. In both cases, the functional hyperbolic absorption model proposed by Wagner and Sedman [1973] was the most representative.

Evaluation of doxorubicin in combination with mafosfamide for in vitro elimination of myeloid and lymphoid tumor cells from human bone marrow

In an attempt to improve in vitro pharmacological purging of autologous grafts, the ability of doxorubicin (DOX), alone and in combination with mafosfamide (AZ), to eliminate tumor cells from human bone marrow was assessed. HL60 and Raji cells were mixed with a 20-fold excess of normal marrow cells and were incubated either with DOX (0.4-3.2 micrograms/ml) for 1 h or AZ (20-140 micrograms/ml) for 30 min or both drugs sequentially. Cytotoxicity was evaluated on tumor cells and GM-CFU by clonogenic assays and on earlier hemopoietic progenitors by liquid long-term marrow cultures (LTMC) for 5 weeks. DOX at 3.2 micrograms/ml and AZ at 140 micrograms/ml spared 1.08 and 1.23% of GM-CFU respectively, and yielded similar tumor cell log-kills for HL60 cells (3.04 and 2.95) and Raji cells (3.24 and 3.40). With the combination of AZ and DOX, the best therapeutic index was observed when the cells were incubated with AZ prior to DOX. Under these conditions, AZ at 80 micrograms/ml together with DOX at 1.6 micrograms/ml significantly increased log-kill values for HL60 cells to 3.96 by a synergistic effect and for Raji cells to 3.85 by an additive effect. In LTMC, GM-CFU recovery after treatment with AZ alone and with the combination of AZ and DOX was 59.9 and 20.0%, respectively, while it was 7.9 and 2.9% at culture initiation. These results suggest that the purging efficiency of DOX is comparable to that of AZ and may be enhanced by combination with AZ.

A comparative in vitro study of transdermal absorption of a series of calcium channel antagonists

The in vitro transdermal absorption of five calcium channel antagonists (nifedipine, nitrendipine, nicardipine, felodipine, and nimodipine) was studied using the skin of hairless rats as a membrane. The aim of this study was to determine the penetration parameters [permeability constant (Kp), lag time (T1, and flux (J)] as measures of the intrinsic transdermal permeabilities of these drugs, in order to predict the potential capacity of these drugs to be formulated in a therapeutical transdermal system (TTS). Reliable prediction of Kp values, using K'w (extrapolated capacity factor in 100% water) and P (n-octanol-water partition coefficient) values as independent variables in the parabolic, bilinear, and hyperbolic functions, were assayed. Nicardipine showed a higher mean transdermal penetration (Kp; 4.9 x 10(-3) cm.h-1) value than the other dihydropyridines. Nifedipine showed the shortest mean T1 value (5.1 h). The permeability rate constants of the calcium channel antagonists assayed can be predicted from their n-octanol-water partition coefficients, using the parabolic function (r = 0.984, p less than 0.01). Nicardipine would be the most suitable candidate for formulation in a TTS design.

Pharmacokinetics and oral bioavailability of carbimide in man

A pharmacokinetic study of carbimide, an inhibitor of aldehyde dehydrogenase, used as an adjuvant in the aversive therapy of chronic alcoholism, has been carried out in male human volunteers for intravenous and oral administration. Carbimide plasma concentrations were determined by a sensitive and specific high performance liquid chromatographic method. The intravenous doses administered were 0.1, 0.3, 0.6, and 1 mg kg-1 and linear pharmacokinetics were observed for this dose range. Elimination half-life and total plasma clearance values ranged from 42 to 52 min and from 14.4 to 20.5 ml kg-1 min-1, respectively. After oral administration of 1 and 1.5 mg kg-1 of carbimide, elimination half-life values were 75 and 61 min, respectively, being higher than the corresponding value obtained after 0.3 mg kg-1 doses, i.e. 39 min. In all cases, rapid absorption was indicated by tmax values ranging from 10.5 to 15.5 min. Absorption was not complete, the oral bioavailability being 53 per cent and 70 per cent for the 0.3 and 1 mg kg-1 carbimide dose, respectively. The data indicate that there is a first-pass effect for carbimide.

Study of the release process of drugs: suppositories of paracetamol

The release process of paracetamol, formulated in suppositories, prepared with four different Suppocire masses (AM, AML, AS2X and AP), having different hydrophilia, supplied by Gattefossé, was investigated. The release study of paracetamol was carried out "in vitro" by means of the Dissotest apparatus (Sotax), built on the base of the flow-through method. The assay conditions were: pH 7.4 and flow rate of 20 ml/min. The release process was evaluated using the following amodelistic parameters: the mean dissolution time (MDT), the variance of dissolution time (VDT), the dissolution efficiency (DE) and the maximum amount dissolved determined experimentally (Qmax). The amodelistic parameters, after their statistical analysis by the Kruskal-Wallis test, followed by the comparison between data pairs by the Mann-Whitney "U" test, proved that there are significant differences (p less than 0.05), with the exception of Qmax, between the four masses tested. This study shows that the masses which have a surfactant in their composition (AS2X and AP) offer a better release of paracetamol than those which have no surfactant (AM and AML).

[In vitro study of platelet preservation during 5 days in reduced-thickness bags]

An in vitro study of platelet concentrates storage for 5 days was performed in PVC bags. Modification of the original three-day containers were introduced by thickness reduction. The results at fifth day were comparable to those at third day in standard plastic bags. During storage, variations of platelet counts were very slight with a low LDH release. PH was stable with a good maintenance of phase microscope platelet morphology. PCO2 and PO2 measurements showed a satisfactory gas permeability which could explain a limited lactate production. If in vivo studies of transfusion recovery confirm these data, platelet concentrates storage could be extended up to 5 days by such modifications of standard three-day PVC bags.

Bioavailability of cyanamide in fasted and unfasted rats

The pharmacokinetics of cyanamide after 35 mg kg-1 intravenous and oral administration to fasted and unfasted rats have been investigated. The plasma level are fitted well by a two-compartment open model. The half-life (t 1/2 beta) of cyanamide in the rat was 1 hour and the plasma clearance (C1p) was 0.02 (1 kg-1) min-1. Food does not appear to modify the absolute bioavailability of cyanamide (F = 93.3 per cent fasted, F = 85.5 per cent unfasted), although it does retard drug absorption.