Optimization of operating conditions for the application of Moringa oleifera (Zogale) seeds extract in water disinfection using response surface methodology

Good quality dry seeds of Moringa oleifera were selected and the seed coat and wings were removed  manually. The kernel was ground to fine powder using the coffee mill attachment of the Moulinex domestic food blender. The ground powder was then sieved through 210 ìm sieve. The seed powder was de-fatted using hexane in electro-thermal Soxhlet extractor. Moringa seeds extract was obtained using the  de-fatted seed cake and aqueous extraction. Different preparations of Moringa extract were added to 10 mL of the Escherichia coli suspension and incubated for 2 h without agitation. Survival of bacterial cells was assessed by making dilution series of bacterial suspensions, plating on non-selective LB medium  agar dishes, and incubating for 48 h at 37°C. Duplicates were made of every individual assay. Colonies  were counted on dishes and the bacterial cell survival ratio was estimated by comparison to a control  experiment where no Moring extract was added. The bacterial removal was optimized by varying the  mixing time, mixing speed, and Moringa seeds extract dosage. Statistical optimization was conducted by using central composite design (CCD). The experimental data was analyzed using statistical software DESIGN EXPERT, V6.4.8 DEC 10 2002 for Windows. The response surface model was used to determine  the optimum operating condition that yields the highest antimicrobial compounds activities from M.  oleifera seeds extracts. A cubic model was fitted to the data. The standard deviation for the cubic model was 0.56, with R2 = 0.9999 and adjusted R2 = 0.9994. The analysis of variance (ANOVA) showed that the effects of mixing time, mixing speed and Moringa dosage were significant (p < 0.05) in the extraction process. The Quadratic model was used in predicting the responses and the optimal conditions were  determined as 31 min mixing time, 85 rpm mixing speed and 3.25 mg/mL Moringa dosage. The results show that the predicted and experimental values were not significantly different and it was thus concluded that the model obtained can be used to optimize the process of antimicrobial bioactive compound  extraction from de-fatted M. oleifera seeds.Key words: Moringa oleifera, seeds extract, bacterial inactivation, optimization, response surface model

Study of ichtyofauna of Daberam Reservoir, Katsina State

Research was carried out to explore the fish species diversity and study some aspects of the Biology of fish of Daberam reservoir, Katsina state, for a period of three month from March to May 2009. 66 Samples of fish were collected from commercial fishermen and experimental fishing gears, preserved in formalin and taken to laboratory for identification. Seven genera comprising eleven species were identified. The regression coefficient (b) were 3.07, 2.91 and 3.21 for the three most commercially importance species in the reservoir i.e. Oreochromis niloticus, Tilapia zilli and Clarias gariepinus respectively, the results indicated Positive allometric growth for O. niloticus and C. gariepinus and negative allometric growth for T. zilli. The mean condition factor (k) was 1.140, with values of 1.027, 1.660, and 0.732 for O. niloticus, T. zilli and C. gariepinus respectively. This result indicates that the fish are not leaving well compared to other freshwater fishes. Key words: Daberam reservoir, fishdiversity, allometric growth, condition facto

Acute Toxicity Study and Hepatocurative Effect of Aqueous Stem Bark Extract of Parkia Biglobosa in Wister albino Rats

Parkia biglobosa plant is widely is used in folk medicinal practices to treat and/or manage various diseases including diabetes, malaria, diarrhea and pains. The current research seek to establish the toxicity profile and hepatocurative ability of aqueous stem bark extract of the plant. Twelve (12) rats were used for Oral LD50 determination, and were grouped into four (4) groups of three rats (3) each. The first three groups were administered with 10 mg/kg, 100 mg/kg and 1000 mg/kg body weight of the extract respectively, while the last group was subdivided into three groups of one rat each and were administered with 2500mg/kg, 3500mg/kg and 5000mg/kg body weight of the extract respectively. For the hepatocurative studies, twenty five (25) experimental rats were divided into five groups of five (5) rats each. Group I served as normal rats, Group II served as test Control while Groups III to V were induced with liver damage and administered with 50mg/kg, 100mg/kg and 150mg/kg of the extract respectively. The LD50 was found to be greater than 5000mg/kg, while phytochemical screening revealed the presence of Flavanoids, Glycosides, Tanins, Saponins, Steroids and Phenols, with the absence of Anthraquinones. For the hepatocurative study, a significant (p<0.0.5) increase in serum albumin and liver enzymes (AST, ALT and ALP) was observed in test control compared to normal control. Upon administration of the extract, a significant (p<0.0.5) fall in Albumin, AST, ALT and ALP was recorded in a dose dependent pattern. No significant difference (p>0.05) was observed between groups in total protein, direct and total bilirubin. The research concludes that the extract is practically non-toxic and possess strong hepatocurative ability which might be due to the phytochemicals present. Keywords: Acute toxiicity; CCl4; Liver; P. biglobosa; Phytochemical and wistar rats. DOI: 10.7176/JNSR/13-16-04 Publication date:September 30th 202

Exome sequencing of the TCL1 mouse model for CLL reveals genetic heterogeneity and dynamics during disease development

The TCL1 mouse model is widely used to study pathophysiology, clonal evolution and drug sensitivity or resistance of chronic lymphocytic leukemia (CLL). By performing whole exome sequencing, we present the genetic landscape of primary tumors from TCL1 mice and of TCL1 tumors serially transplanted into wildtype recipients to mimic clonal evolution. We show that similar to CLL patients, mutations in mice are frequently subclonal and heterogenous among different primary TCL1 mice. We further describe that this molecular heterogeneity mirrors heterogenous disease characteristics such as organ infiltration or CLL dependent T cell skewing. Similar to human CLL, we further observed the occurrence of novel mutations and structural variations during clonal evolution and found plasticity in the expansion of B cell receptor specific subclones. Thus, our results uncover that the genetic complexity, pathway dependence and clonal dynamics in mouse CLL are in relevant agreement to human CLL, and they are important to consider in future research using the TCL1 mouse for studying CLL

PI3Kδ inhibition elicits anti-leukemic effects through Bim-dependent apoptosis

PI3Kδ plays pivotal roles in the maintenance, proliferation and survival of malignant B-lymphocytes. Although not curative, PI3Kδ inhibitors (PI3Kδi) demonstrate impressive clinical efficacy and, alongside other signaling inhibitors, are revolutionizing the treatment of hematological malignancies. However, only limited in vivo data are available regarding their mechanism of action. With the rising number of novel treatments, the challenge is to identify combinations that deliver curative regimes. A deeper understanding of the molecular mechanism is required to guide these selections. Currently, immunomodulation, inhibition of B-cell receptor signaling, chemokine/cytokine signaling and apoptosis represent potential therapeutic mechanisms for PI3Kδi. Here we characterize the molecular mechanisms responsible for PI3Kδi-induced apoptosis in an in vivo model of chronic lymphocytic leukemia (CLL). In vitro, PI3Kδi-induced substantive apoptosis and disrupted microenvironment-derived signaling in murine (Eμ-Tcl1) and human (CLL) leukemia cells. Furthermore, PI3Kδi imparted significant therapeutic responses in Eμ-Tcl1-bearing animals and enhanced anti-CD20 monoclonal antibody therapy. Responses correlated with upregulation of the pro-apoptotic BH3-only protein Bim. Accordingly, Bim−/− Eμ-Tcl1 Tg leukemias demonstrated resistance to PI3Kδi-induced apoptosis were refractory to PI3Kδi in vivo and failed to display combination efficacy with anti-CD20 monoclonal antibody therapy. Therefore, Bim-dependent apoptosis represents a key in vivo therapeutic mechanism for PI3Kδi, both alone and in combination therapy regimes

A retinoic acid-dependent stroma-leukemia crosstalk promotes chronic lymphocytic leukemia progression

In chronic lymphocytic leukemia (CLL), the non-hematopoietic stromal microenvironment plays a critical role in promoting tumor cell recruitment, activation, survival, and expansion. However, the nature of the stromal cells and molecular pathways involved remain largely unknown. Here, we demonstrate that leukemic B lymphocytes induce the activation of retinoid acid synthesis and signaling in the microenvironment. Inhibition of RA-signaling in stromal cells causes deregulation of genes associated with adhesion, tissue organization and chemokine secretion including the B-cell chemokine CXCL13. Notably, reducing retinoic acid precursors from the diet or inhibiting RA-signaling through retinoid-antagonist therapy prolong survival by preventing dissemination of leukemia cells into lymphoid tissues. Furthermore, mouse and human leukemia cells could be distinguished from normal B-cells by their increased expression of Rarγ2 and RXRα, respectively. These findings establish a role for retinoids in murine CLL pathogenesis, and provide new therapeutic strategies to target the microenvironment and to control disease progression