Maturation, sex ratio and fecundity of the Nile perch Lates niloticus (L.) (Pisces: Centropomidae) in Lake Chamo, Ethiopia

Length-weight relationship, length at first maturity and sex ratio of the Nile perch Lates niloticus (L.) were studied from 342 fish samples collected between February 1995 and May 1996. The relationship between total length (TL) and total weight (TW) for both sexes was curvilinear and statistically significant. The regression equation for the males was TW=0.0044TL3.27 (r2=0.978,

Fluctuaciones temporales en el fitoplancton y contenido de microcistinas intracelulares en cuatro lagos Nicaragüenses

La contaminación de los ecosistemas acuáticos por el enriquecimiento de nutrientes permite la proliferación de microalgas o florecimientos que pueden tener potencial tóxico si los grupos dominantes son cianobacterias. Por lo que este estudio tuvo como objetivos conocer las fluctuaciones temporales de las especies fitoplanctónicas presentes en cuatro lagos nicaragüenses (Cocibolca, Xolotlán, Masaya y Tiscapa), con énfasis en las cianobacterias y estimar su potencial tóxico por microcistinas. Se realizaron 11 muestreos en los lagos de interés en los que se analizaron el contenido de Clorofila a, fitoplancton cuantitativo, identificación taxonómica hasta el nivel de género y especies así como el contenido de microcistinas por ELISA. La Clorofila a osciló entre un valor no detectado en el Lago Xolotlán (noviembre) y 37 μg/l detectados en Tiscapa (agosto). Los géneros fitoplanctónicos más representativos detectados durante la mayor parte del período muestreado en tres de los cuatro lagos nicaragüenses estudiados (Cocibolca, Tiscapa y Masaya) fueron cianobacterias, entre los que se distinguen Anabaenopsis, Merismopedia, Chroococcus y Lyngbya. El Lago Xolotlán presentó dominancia de taxas de diatomeas (Stephanodiscus sp, Synedra sp, y Cyclotella meneghiniana). Los resultados de microcistinas muestran valores bajos (< 0.003 hasta 0.069 μg/l) en los cuatro lagos estudiados, siendo los lagos Xolotlán y Masaya los que presentaron las mayores concentraciones en los meses de mayo y julio, respectivamente. Al comparar estos resultados con los reportados para ecosistemas lacustres del mundo para el mismo período se puede inferir un bajo potencial tóxico por microcistinas en los cuatros lagos nicaragüenses. Sin embargo, no se puede descartar la toxicidad debida a otras toxinas naturales dada la dominancia de géneros de cianobacterias por lo que se recomienda seguir realizando monitoreos de este tipo e incluir en el conteo a pico-cianobacterias

Clinical and genetic studies of ETV6/ABL1-positive chronic myeloid leukaemia in blast crisis treated with imatinib mesylate.

Most chronic myeloid leukaemia (CML) patients are genetically characterized by the t(9;22)(q34;q11), generating the BCR/ABL1 fusion gene. However, a few CML patients with rearrangements of 9q34 and 12p13, leading to ETV6/ABL1 chimaeras, have also been reported. Here we describe the clinical and genetic response to imatinib mesylate treatment of an ETV6/ABL1-positive CML patient diagnosed in blast crisis (BC). A chronic phase was achieved after acute myeloid leukaemia induction therapy. Then, treatment with imatinib mesylate (600 mg/d) was initiated and the effect was assessed clinically as well as genetically, including by repeated interphase fluorescence in situ hybridization studies. Until d 71 of imatinib mesylate therapy, stable improvements in the clinical and laboratory features were noted, and the frequency of ABL1-rearranged peripheral blood cells decreased from 56% to 11%. At d 92, an additional t(12;13)(p12;q13), with the 12p breakpoint proximal to ETV6, was found. The patient relapsed into BC 126 d after the start of the imatinib mesylate treatment and succumbed to the disease shortly afterwards. No mutations in the tyrosine kinase domain of ABL1 of the ETV6/ABL1 fusion were identified in the second BC. However, whereas the ETV6/ABL1 expression was seemingly the same at diagnosis and at second BC, the expression of ETV6 was markedly lower at the second BC. This decreased expression of wild-type ETV6 may have been a contributory factor for the relapse

Quantification and three-dimensional imaging of the insulitis-induced destruction of ß-cells in murine type 1diabetes

OBJECTIVE: The aim of this study was to refine the information regarding the quantitative and spatial dynamics of infiltrating lymphocytes and remaining β-cell volume during the progression of type 1 diabetes in the nonobese diabetic (NOD) mouse model of the disease. RESEARCH DESIGN AND METHODS: Using an ex vivo technique, optical projection tomography (OPT), we quantified and assessed the three-dimensional spatial development and progression of insulitis and β-cell destruction in pancreata from diabetes-prone NOD and non–diabetes-prone congenic NOD.H-2b mice between 3 and 16 weeks of age. RESULTS: Together with results showing the spatial dynamics of the insulitis process, we provide data of β-cell volume distributions down to the level of the individual islets and throughout the pancreas during the development and progression of type 1 diabetes. Our data provide evidence for a compensatory growth potential of the larger insulin(+) islets during the later stages of the disease around the time point for development of clinical diabetes. This is in contrast to smaller islets, which appear less resistant to the autoimmune attack. We also provide new information on the spatial dynamics of the insulitis process itself, including its apparently random distribution at onset, the local variations during its further development, and the formation of structures resembling tertiary lymphoid organs at later phases of insulitis progression. CONCLUSIONS: Our data provide a powerful tool for phenotypic analysis of genetic and environmental effects on type 1 diabetes etiology as well as for evaluating the potential effect of therapeutic regimes

Comparison of busulphan, hydroxyurea and allogeneic bone marrow transplantation (BMT) in chronic myeloid leukaemia: BMT prolongs survival

Introduction: Whether busulphan -treated patients develop blastic transformation earlier than hydroxyurea treated has been a controversial issue. In a randomised prospective study, we examined the busulphan versus hydroxyurea influence on time to blast crisis and on survival. When we opened our study in 1984, the clinical benefit of allogeneic bone marrow transplantation (BMT) was not well known; to follow up the long-time outcome of this treatment was therefore of great interest. Materials and methods: Previously untreated CML patients were randomly started on either hydroxyurea (30 mg/kg/day) or busulphan (0. 1 mg/kg/day). The end points of the study were overall survival and time to blast crisis. A total of 26 patients subsequently underwent BMT. Results: A total of 179 patients were randomised.. 90 to hydroxyurea, and 89 to busulphan treatment. There was no significant difference in survival between hydroxyurea- and busulphantreated patients (P=0.46) median survival was 3.5 and 3.2 years, respectively. In all, 85 of the patients were subsequently diagnosed with blast crisis, 41 in the busulphan and 44 in the hydroxyurea group. There was no significant difference between the two groups (P = 0.91). The 26 patients who were allotransplanted survived significantly longer than those who were not transplanted (P=0.0001). The 5-year-survival rates were 50 and 22% and the 10-year-survival rates were 46 and 2%, respectively. The median survival was 4.7 years for the transplanted and 3.3 years for the nontransplanted patients. Conclusion: We did not find any difference between hydroxyurea and busulphan treatment, either in overall survival or in blast crisis-free survival; transplanted patients survived significantly longer than nontransplanted patients