Tertiary conformational transition constant of guinea pig haemoglobin determined from the reaction of 5,5′-dithiobis (2-nitrobenzoate) with CysF9[93]β and CysH3[125]β

We have determined Kequ, the equilibrium constant for the reaction of 5,5′-dithiobis(2-nitrobenzoate) — DTNB — with the CysF9*93+β and CysH3*125+β sulphydryl groups of various derivatives of guinea pig haemoglobin at 25oC. In the pH range 5.6 to 9, Kequ decreases almost 50-fold: from a mean of 3.45 ± 0.2 to a mean of 0.073 ± 0.01. Quantitative analyses of the pH dependence profiles of Kequ enable the determination of Krt, the equilibrium constant for the rt tertiary conformational transition of haemoglobin. The t isomer population is 53.9 (± 2)%. In the r conformation the pKas of the amino acid residues whose ionisations are coupled to the reaction of DTNB with the sulphydryl groups are 5.74 ± 0.02 — for a combination of HisNA2*2+β and HisH21*143+β) — and 7.74 ± 0.2 for ValNA1*1+β); in the t conformation they are 5.88 ± 0.05 and 8.23 ± 0.1, respectively.Keywords --- guinea pig haemoglobin; sulphydryl groups; 5,5′-dithiobis(2-nitrobenzoate); equilibrium constants; tertiary conformational transition

Transition of haemoglobin between two tertiary conformations: Inositol hexakisphosphate increases the transition constant and the affinity of sheep haemoglobin for 5,5′-dithiobis(2-nitrobenzoate)

The equilibrium constant (Kequ) for the reaction of 5,5′-dithiobis(2-nitrobenzoate) — DTNB — with the CysF9 [93]β sulphydryl group of the haemoglobins of the sheep decreases by about two orders of magnitude between pH≈5.6 and 9.2: from a mean of 7.2±1 to a mean of 0.044±0.01. Calculations from the pH dependence of Kequ show that in the r⇌t tertiary conformational transition of haemoglobin the t isomer population is 50.7 and 61.8% for the major and minor haemoglobins, respectively. In the presence of inositol hexakisphosphate (inositol-P6), Kequ increases for both haemoglobins by about an order of magnitude through most of the pH range. The t isomer population also increases to 82.1 and 79.6% for the major and minor haemoglobins, respectively. These results indicate that inositol-P6 increases the affinity of the sulphydryl for DTNB by increasing the population of the t isomer. It is highly probable that a minimum fourstate model that includes the r⇌t transition is required for a full understanding of haemoglobin function

Tertiary conformational transition in sheep hemoglobins induced by reaction with 5,5´-dithiobis(2-nitrobenzoate) and by binding of inositol hexakisphosphate

We have determined the second-order reverse rate constant, kR, for the reaction of 5,5´-dithiobis(2- nitrobenzoate) – DTNB – with sheep hemoglobins as a function of pH from values of the second-order forward rate constant, kF, and the equilibrium constant, Kequ, at 25 °C: kR¼ kF Kequ. We demonstrate that (i) inositol hexakisphosphate (inositol-P6) decreases kF and kR by increasing Krt, the r⇌t tertiary conformation transition constant; (ii) the conformation favored for both the forward and reverse reactions is the r conformation. For stripped hemoglobin we obtain from the kF data a t isomer population of 34.6% (±14) prior to reaction with DTNB; from the kR data we calculate a t isomer population of 44.8% (±4) following reaction with DTNB. In the presence of inositol-P6 the latter value is increased to 79.5% (±2). These results demonstrate that an allosteric transition occurs on reaction with DTNB and on inositol-P6 binding

FARMERS’ PERCEPTION OF “LATOJU OJA†RADIO PROGRAMME IN IDDO LOCAL GOVERNMENT AREA OF OYO STATE, NIGERIA

Radio is noted to be one of the most important sources of reaching farmers in many developing countries because of its cheapness and wide coverage. The study assessed farmers’ perception of “Latoju Oja†radio programme of Radio Nigeria in Iddo Local Government of Oyo State Nigeria. Three major towns were purposively selected because of their high commercial and farming activities. From each town thirty-five respondents were selected using the snowball technique to make one hundred and five respondents for the study. Descriptive and inferential statistics such as frequency counts, percentages and chi-square analysis were used in analyzing the data obtained. The study revealed that 60% of the respondents were 40 years and above, 95% were male, 88% were married while majority (68.8%) of the respondents indicated that they had completed secondary school education, with very few (5%) attending tertiary institutions. The programme listened to “regularly†by the respondents on radio were news (75.2%), religious issues (51.2%) and agricultural issues (48.7%). On respondents’ frequency of listening to “Latoju Oja†programme, 57.5% listen regularly while 35% listen occasionally. The study revealed that the respondents are positively disposed to “Latoju Oja†radio programme.  Chi-square analysis showed that there were no significant associations between sex, religion, marital status and respondents’ perception, while age and educational level showed significant associations with farmers’ perception. In addition, Chi-square analysis showed that no significant association exists between the respondents’ listening frequency and perception of “Latoju Oja†Programme. The study concluded that more markets should be included in the radio programme, since farmers have positive disposition to the programme to enable farmers have a more detailed knowledge of commodities prices in more markets in the area.Â

Isothermal, kinetics and thermodynamics studies of the biosorption of Pb (II) ion from aqueous solution using the scale of croaker fish (Genyonemus lineatus)

Biosorbent prepared from the scale of croaker fish (Genyonemus lineatus) has been used for the removal of Pb(II) ion from aqueous solution in a batch system. The effects of some important parameters such as pH, initial metal concentration, temperature and biosorbent dosage on biosorption capacity were investigated. Equilibrium time for the biosorption process is 20 and 30 min at lower and higher concentrations, respectively. The process at 28 °C is in agreement with a pseudo-second-order kinetics model. The equilibrium data obeyed the Langmuir adsorption isotherm with a maximum monolayer adsorption capacity of 14.58 mg g−1. The study showed that the sorption process depends on biomass dosage, temperature, pH and initial metal ion concentration. The calculated thermodynamics parameters (ΔGo, ΔHo and ΔSo) indicated that the biosorption of the metal ion onto fish scale is feasible, spontaneous and exothermic in nature

Microbial Quality of Public Swimming Pools in Lagos

The microbial quality of some public swimming pools in Lagos State, Nigeria was investigated to determine possible risks of infections to swimmers. Ten swimming pools (Pools AJ) were investigated for their microbial and physico-chemical qualities. The pH of the pools ranged from 5.24-8.71 and the residual chlorine ranged from 0.01-0.07. Water samples from the pools were cultured on differential and selective media. The microbial loads varied with different swimming pools. The fungal population ranged from 0-4.7× 10 4 cfu ml-1, while the bacterial population ranged from 0-1.12 x 10 5 cfu ml-1. Eight bacterial isolates were obtained and identified using Microbact 24E kit. Fungal isolates (6) were identified by microscopy, Gram’s staining and chloramphenicol test. The isolates include Aeromonas hydrophila (4), Burkolderia pseudomallei (2), Serratia marcescens (1), Enterobacter agglomerans (1), Candida albicans (3), Saccharomyces spp.(2) and Aspergillus flavus (1). Antifungal sensitivity test showed 50% susceptibility to nystatin and 50% resistance to voriconazole, while the bacteria were resistant to most of the antibiotic tested. The Multiple Antibiotics Resistance (MAR) index for the isolates ranged from 0.125 to 1.000. The feedback from the questionnaires administered, showed that unhygienic practices and maintenance of pools could contribute to low levels of swimming pool water quality. The high microbial loads and the types of microorganisms isolated from the pools show that contaminated swimming pools can constitute a serious public health hazard to the users

Perturbation of spectra properties of 3,4-diphenyl thiophene by polar and non polar solvents

The UV/visible spectra of 3,4-diphenyl thiophene were obtained in various solvents (both polar and non polar). The wave number of transition energies, corresponding molar absorp-tivities and oscillation frequency were determined. Three bands were obtained in solvents such as cyclohexane, propan-2-ol, methanol and ether. Two bands are obtained in n-hexane and 1,2-dichloroethane, while 1,4-dioxane give a single band. Transitions are assigned to these bands according to their shift due to the effect of solvents

Bioassay of herbal mosquito repellant formulated from the essential oil of plants

ABSTRACT Malaria, Dengue fever and Filariasis, are serious public health problem in tropical regions, especially in Africa and Asia and are transmitted through mosquito bites. For effective control of these diseases, therefore, there is need to prevent individual from mosquito bites. The effective and safe method is the use of mosquito repellent naturally obtained from medicinal plants instead of commonly available synthetic insecticides and repellents such as Organo Phosphorus Carbamate, N, N-Diethyl-3-methylbenzamide (DEET), and Dichloro Diphenyl Trichloroethane (DDT) which are carcinogenic and non eco-friendly. In this study, the repellency activities of four formulated herbal mosquito repellents from the essential oils of some selected MAPPs of Nigeria were evaluated. The essential oils were extracted by hyrodistillation method at 50°C using all glass Clevenger apparatus. These were then stored at 4 o c in the refrigerator pending further studies.Graded concentrations (6%, 8%, 10% and 12%) of the essential oils in a complex solution of polyethylene glycol, ethanol and water were prepared and their mosquito repellency activities was carried out in the laboratory against Standard Kisumu Strains of Anopheles gambiae. The result showed that both 8% and 10% formulations have the most promising activity exhibiting 68-95% repellency activities lasting for 2hours. The standard (odomos ® mosquito repellent cream) exhibited 75-100% repellency activities which also lasted for 2hours as compared to 8% and 10% formulations. The present study demonstrates the potential for using essential oils from medicinal plants as mosquito repellent

Anticarcinogenic effect of alpha-lipoic acid and <i>Jatropha gossypifolia</i> leaves against cypermethrin-induced genotoxicity in rats

Background: Cypermethrin (Cyp), a synthetic pyrethroid developed for agricultural and public health applications, has become harmful to the environment and mammalian life owing to indiscriminate use. Aim: This study aimed to investigate the protective effect of the methanolic extract of Jatropha gossypifolia leaves against Cyp-induced genotoxicity in rats using alpha-lipoic acid (α-LA) as standard drug. Method: Fifty-six male Wistar rats, assigned to eight groups of seven animals each, were treated orally for 28 days as follows - Group 1: only corn oil (Control); Group 2: 20 mg/kg body weight (b.wt) of Cyp; Groups 3, 4 and 5: Cyp + 50 mg/kg b.wt of J. gossypifolia, Cyp + 100 mg/kg b.wt of J. gossypifolia and Cyp + 50 mg/kg b.wt of α-LA, respectively; Groups 6, 7 and 8: J. gossypifolia (50 mg/kg b.wt), J. gossypifolia (100 mg/kg b.wt) and α-LA (50 mg/kg b.wt), respectively. The P53 was assayed for using the plasma, while the micronucleus assay was carried out on the bone marrow. Results: Results showed that exposure to Cyp significantly increased the number of micronucleated polychromatic erythrocytes (86.70%) as well as p53 concentration in both the liver and plasma (200.00% and 125.53%) compared to the control. Co-administration with methanolic extract of J. gossypifolia leaves significantly reversed these alterations in a dose-dependent manner. Conclusion: The methanolic extract of J. gossypifolia leaves has the potential to ameliorate Cyp-induced genotoxicity in rats, and also, the toxicological evaluations of the plant extract and α-LA showed that it is relatively safe for use at the doses investigated

Enhancing Training of Staff of the Agricultural Development Programme for Effective Agricultural Extension Service Delivery in Nigeria

This paper, identified the areas where staff of the Agricultural Development Programme (ADP) that carry out grassroots extension service delivery need to be trained and the field problems requiring research intervention. Secondary data from Annual Performance Survey (APS) report of NAERLS and NPAFS between 2010 and 2012 were used. The data were analyzed using descriptive statistics. Results showed that the most frequent key areas where trainings needed were long term course, short term refresher trainings, pre-season training, management training for administrative staff, specialized for subject matter specialist and data collection processing/analysis. The study further revealed that the development of livestock feed formula from local materials, heat-tolerant and disease resistant varieties of tomato and wheat were the most pressing problems requiring the researchers’ attention. It is recommended that ADPs should be given periodic training by relevant organizations on the identified areas and researchers should focus their researches more on the identified problems requiring research intervention. Moreover, state governments should adequately sponsor trainings of ADPs in their various states. This will strengthen the ADPs skills and increase their productivities for an effective extension service delivery in Nigeria