Cohort event monitoring of patients treated for uncomplicated malaria with artemisinin-based combination therapies in selected hospitals and community pharmacies in Nigeria.

AIMS AND OBJECTIVES: The study was designed with the broad objective of determining the safety profile of artemisinin-based combination therapies amongst Nigerian population. PATIENTS AND METHODS: This was a cohort event monitoring (CEM) programme involving monitoring adverse events (AEs) in malaria patients treated with either artemether-lumefantrine (AL) or artesunate-amodiaquine (AA) in healthcare facilities in Nigeria. The study involved continuous enrolment of patients with malaria and treated with either AL or AA at the various sites until a total cohort of 600 patients were enrolled at each site. Patients were monitored from the onset of therapy, and on days 3 and 7 from the first day of treatment to identify AEs that may occur. RESULTS: A total of 6102 AEs were recorded in 10,259 patients monitored during the programme. Of 4896 patients who received AA, 4233 (86.5%) patients reported at least one AE while 1869 (34.8%) AEs out of 5363 patients who received AL were reported (P = 0.010). The predominant incidence of each specific AE reported in each group among the patients who received AA and AL includes body weakness 30.8%/7.5%, dizziness 10.3%/3.9%, restlessness 5.02/1.12%, vomiting 3.5/1.03% and drowsiness 3.1/1.5% for AA and AL, respectively. There were more AEs among patients with co-morbid conditions and patients in the younger age groups (9-<15 years), P = 0.000. CONCLUSIONS: Various types of AEs were seen and documented during the CEM programme. The findings suggested that the AA/AL monitored during this programme was generally safe and remarkably well tolerated among the Nigerian populations.

Cytogenetic studies in a canine mammary tumor.

In a 9-year-old female dog (Basset Artesian Normand) with a mammary adenocarcinoma, cytogenetic evaluation of tumor cells showed a chromosome number of 76 in most metaphases (95%). The following abnormalities were found: symmetric metacentric chromosomes 1 and 6, centric fusion 3/38, a marker X-chromosome (Xmar) and a biarmed small marker chromosome (mar). In the remaining metaphases (5%) there were additional biarmed marker chromosomes present.

Polymorphisms of NORs and Heterochromatin in the Horse and Donkey.

Chromomycin A3 (CMA3) banding in mitotic sets of the Equidae horse and donkey were used to demonstrate both constitutive heterochromatin and R-banding. Intra and Interindividual variation In the size of the heterochromatic blocks was observed In many cases. CMA3-posittve telomeric heterochromatin blocks appeared on several chromosomes of the horse and donkey. Some of them were especially spectacular in the donkey. A sequential silver NOR-chromomycin A3/distamycln A-DAPI (CDD) staining procedure led to the detection of the localization of active nucleolus-organizing regions (NORs) and to the identification of chromosomes. The data revealed individual specific NOR patterns in both species.

Chromosomal hyperdiploidy in a feline sarcoma.

An eight-year-old male cat developed a sarcoma. The cytogenetic evaluation of the tumour cells showed the presence of hyperdiploidy (range 40 to 46 chromosomes). This hyperdiploidy was encountered in all the cells examined. Extra-chromosomes numbers C1, C2, B4, D4 and E3 were mainly responsible for the hyperdiploid chromosomal complements. There was a high incidence of monosomy E3.

Mithun cross siri hybrids: cyto- and immunogenetic examinations and characterisation of abnormal spermatogenesis.

Cytogenetic studies of the mithun (Bos frontalis), the siri (Bos indicus) and their hybrids, as well as histological examinations of testes and epididymis of siri and hybrids were undertaken to throw further light on male hybrid infertility and interspecies incompatibility, in order to facilitate the possible development of a stable interspecies crossbreed which would be similar to the highly profitable jatsum, the female mithun cross siri hybrid. In both species there are distinct centromeric heteromorphisms which should provide a rich source of genetic markers for tracing chromosomes in controlled hybrid programmes. The nucleolar organisers in the F1 hybrids were derived from both parents, in contrast to other interspecies hybrids where the nucleolar organisers of one species tend to be suppressed by the other. This indicates a relatively close relationship between mithun and siri and supports the prospect of success for developing a stable crossbreed. Transferrins which may also be a useful source of genetic markers were identified and differences between siris and mithuns noted, especially in the D-bands. No A-bands were found in the siris and no E-bands in the mithuns. Whether this is a breed or species characteristic will have to be confirmed by examination of more animals. The findings on blood groups and haemoglobins, including differences between the two species, were similar to results obtained previously. In meiosis the sex vesicles were intact which indicates that infertility and incompatibility factors should be located in autosomes. In cytogenetic and histological examinations the testes of the siris were comparable to those of European cattle, while in all hybrids spermatogenetic activity was deficient although there were great differences between and within generations. While the exact mechanism of this diversity is not known at this stage, it should make it possible to select for increased male hybrid fertility which would be a prerequisite for developing a stable interspecies crossbreed. This selection would be facilitated by correlating infertility and incompatibility with genetic profiles and markers. A mithun cross siri crossbreed would also serve as a model for other interspecies breeding.

Trisomy D2 in a feline neurofibroma.

An eight-year-old female cat developed a skin neurofibroma. The cytogenetic evaluation of the tumour cells showed the presence of a high percentage (16.4 per cent) of trisomic cells. The trisomy concerned chromosome number D2.

Genetic characterisation of the mithun (Bos frontalis) and studies of spermatogenesis, blood groups and haemoglobins of its hybrids with Bos indicus.

The mithun (Bos frontalis) and its hybrids with Bos indicus were studied to provide further cytogenetic information which might throw light on the mechanisms of the male hybrid infertility and facilitate the establishment of a stable crossbreed. It was shown that compared with conventional cattle the mithun has a homozygous, species specific 2/27 centric fusion which reduced the diploid chromosome number from 60 to 58. This provided further proof that Robertson translocation-type rearrangements have been the major source of interspecies karyotype differences in the evolution of the Bovidae. In the mithun there was also significant polymorphism between centromeres of non-homologous chromosomes and there was heteromorphism between several homologous chromosomes which could possibly serve as useful genetic markers for breeding programmes. In F1 hybrids spermatogenesis progressed to a relatively advanced stage, without going so far as to produce spermatozoa. In back crosses to B indicus spermatogenesis progressed further so that spermatozoa could be seen, though not as numerous as in normal bulls. In most hybrids there were haemoglobin bands which corresponded either to Hb A or Hb B of cattle but were much wider. It was shown that these were a combination of Hb Mi derived from the mithun and Hb A or Hb B derived from B indicus. In a few hybrids there were only Hb Mi. In these cases Hb Mi had been present in both parents and proved that the dam was not a pure siri. The possible mechanism of hybrid male infertility is discussed including faults in the epistatic gene effect between chromosomes and changes in the degree of association of centromeric regions in interspecies hybrids. It is suggested that additional cytogenetic examination of blood lymphocytes and especially of testicles would help the understanding of the fertility barriers of hybrid males and would make a breeding programme for a stable crossbreed possible.

Near triploidy in a feline fibrosarcoma.

A seven-year-old male cat developed a subcutaneous fibrosarcoma. The numerical cytogenetic evaluation of the tumour revealed the presence of 69.2% of cells in the near-triploid chromosome range between 51 and 64. The copy numbers of the different chromosomes were widely distributed from monosomies up to heptasomies. Two giant chromosomes were regularly present.

Localisation of NORs and counterstain-enhanced fluorescence studies in Salmo gairdneri and Salmo trutta (Pisces, Salmonidae).

The karyotypes of the rainbow trout (Salmo gairdneri R.) and the brown trout (Salmo trutta L.) were analyzed by means of silver staining and the chromomycin A3/distamycin A/DAPI fluorescence banding technique. The nucleolus organizer regions (NORs) were localized at the secondary constrictions of chromosome no. 14 in S. gairdneri and of chromosome no. 10 in S. trutta. Additional silver positive dots were observed at or close to several centromeres in S. gairdneri. Brilliant chromomycin A3 (CMA3) fluorescence heterochromatin blocks were localized on both sides of the nucleolar constrictions in S. gairdneri. A polymorphic CMA3 positive band was detected close to the NORs of S. trutta. No distamycin A/DAPI intense heterochromatin blocks were detected in the genomes of the two Salmo species investigated.

Heterochromatins and band karyotypes in three species of salmonids.

The heterochromatins of rainbow trout (Salmo gairdneri R.), brown trout (Salmo trutta fario L.) and brook trout (Salvelinus fontinalis M.) were characterized by sequential chromomycin A3/distamycin A/DAPI (CDD) and DAPI/actinomycin D (DAPI/AmD) fluorescence. On most biarmed chromosomes, an equilocal localization of prominent DAPI/AmD positive, chromomycin A3 negative, AT-rich blocks at the centromeres were observed in all three species. Band karyotypes of the three species were established. In rainbow trout, several DAPI/AmD positive heterochromatin blocks behaved positive in a silver-staining method. Mitotic and interphase studies proved the presence of inter-individual NOR variation in brown trout. The NORs of brook trout were localized on chromosomes 5, 10, 14, 15 and 29.

NORs, heterochromatin, and R-bands in three species of Cervidae.

Chromomycin A3 banding of the chromosomes of three species of Cervidae (red deer, fallow deer, roe deer) allows the demonstration of both centromeric constitutive heterochromatin and R-banding patterns useful for identifying all the chromosomes of a given karyotype. In all three species significant amounts of chromomycin-bright heterochromatin are present at the centromeres of all autosomes. The X chromosomes of all investigated species contained appreciable amounts of centromeric heterochromatin. AgNO3 staining was applied sequentially to detect the location of active nucleolus organizer regions (NORs). The distribution of NORs was reasonably conservative in the investigated species.

Maturation competence and chromatin behaviour in growing and fully grown cattle oocytes.

Chromatin configurations of cattle oocytes from different follicle sizes were classified in three chromatin categories. Early diplotenes, dictyate-like structures, more progressed diplotenes and early diakinesis and metaphases were found. In follicle group A (0.4-0.9 mm) immature diplotenes predominated (82.3%), and a rather low maturation competence was observed (12.1%). With increasing follicle size the maturation competence was improved to 47.8% metaphases II in follicle group C (3-8 mm). Impressive CMA3 positive blocks were visualized especially in early diplotenes. Heterochromatic CMA3 positive clusters surrounded the nucleolus.

Heterochromatin composition and nucleolus organizer activity in four canid species.

Sequential staining with a counterstain-contrasted fluorescent banding technique (chromomycin A3-distamycin A-DAPI) revealed the occurrence of distamycin A-4,6-diamidino-2-phenylindole (DA-DAPI) staining heterochromatin in the centromeric regions of chromosomes 33, 36, 37, and 38 in the wolf (Canis lupus pallipes) and of chromosomes 13, 16, and 23 in the blue fox (Alopex lagopus). The red fox (Vulpes vulpes) lacked such regions. Staining with DAPI--actinomycin D produced a QFH-type banding pattern with clearcut differences in the staining behaviour of DA-DAPI positive regions between these three canid species. Staining with the fluorochrome D 287/170 did not preferentially highlight any of the DA-DAPI positive regions in any of them. Counterstain-enhanced chromomycin A3 R-banding and studies of nucleolus organizer region location and activity confirmed a close relationship between the karyotype of the wolf and the domestic dog. Few heterochromatic marker bands were encountered in these two species, but heterochromatin polymorphism was evident in the blue fox.

In vivo plasmid DNA electroporation generates exceptionally high levels of epitope-specific CD8+ T-cell responses.

Based on observations that DBA/2 mice develop a highly specific response towards an HLA-Cw3-derived epitope, consisting entirely of CD8+CD62L-Vbeta10+ cells, we have established an in vivo mouse model for screening a variety of immunization approaches. Responder cells were readily detectable in small samples of the peripheral blood using three-color FACS analysis. This permitted multiple, sequential determination of CD8+ T-cell responses in living animals at a very high degree of precision. In vivo electroporation delivery of expression construct plasmids, outclassed the other approaches tested. Dominant, specific responses were induced already upon a single administration. Both the peak and the longevity of the response resembled those that are generated by the most active viral infections. The induced CTLs rejected epitope-bearing tumor cells in vivo and released interferon-gamma upon stimulation with the correct MHC::peptide combination in vitro. The potent in vivo response was not influenced by known modulators of the innate immune system, such as CpG DNA and LPS content. In vivo electroporation thus deserves consideration in the future in antitumor and antiviral immunization approaches, where CD8+ T cells play a predominant role.

Characterization of heterochromatin by sequential counterstain-enhanced fluorescence in three domestic bird species: Meleagris gallopavo, Columba livia domestica, and Anser anser L.

The karyotypes of three avian species--Meleagris gallopavo, Anser anser L., and Columba livia domestica--were investigated by means of counterstain-enhanced fluorescence techniques (chromomycin A3/distamycin A/DAPI followed by DAPI/actinomycin D staining). A heterochromatin characterization of macro- and microchromosomes was performed. CMA3-positive (GC-rich) regions in the turkey included the telomeres of chromosomes 1, 3, 4, and Z. In the goose, the chromosome 2 was also CMA3-bright at the telomeres. The W chromosome possessed large amounts of CMA3-bright material on the short arm in both the turkey and the goose. Two types of centromeric heterochromatin were distinguished on acro- to telocentric chromosomes 6 to 14 in the pigeon. The microchromosomal heterochromation of the turkey and goose was GC-rich but had a high degree of variation. In the pigeon, several microchromosomes possessed predominantly AT-rich heterochromatin.

Levels of conservation and variation of heterochromatin and nucleolus organizers in the Bovidae.

Chromomycin A3 banding of the mitotic sets of 10 species of Bovidae (cattle, wisent, yak, banteng, gaur, red buffalo, swamp buffalo, sheep, mufflon, and goat) serves to demarcate both centromeric constitutive heterochromatin and R-banding patterns capable of identifying all the chromosomes within a given complement. In all species significant amounts of chromomycin-bright heterochromatin are present at the centromeres of all autosomes, though there was a high degree of intra- and inter-individual variation in the size of the heterochromatic blocks. Marked interspecies differences in the centromeric patterns were evident. The X chromosomes contained appreciable amounts of centromeric heterochromatin only in the two buffaloes. All the animals studied lacked distamycin A - diamidinophenylindole type heterochromatin. AgNO3 staining was applied sequentially to detect the location of active nucleolus organizer regions (NORs). The distribution of NORs was reasonably conservative in most of the species. An exceptional situation was found in the two buffaloes, where only one NOR pair matched with the standard karyotype of the Bovidae.