The structural organization and protein composition of lens fiber junctions.

The structural organization and protein composition of lens fiber junctions isolated from adult bovine and calf lenses were studied using combined electron microscopy, immunolocalization with monoclonal and polyclonal anti-MIP and anti-MP70 (two putative gap junction-forming proteins), and freeze-fracture and label-fracture methods. The major intrinsic protein of lens plasma membranes (MIP) was localized in single membranes and in an extensive network of junctions having flat and undulating surface topologies. In wavy junctions, polyclonal and monoclonal anti-MIPs labeled only the cytoplasmic surface of the convex membrane of the junction. Label-fracture experiments demonstrated that the convex membrane contained MIP arranged in tetragonal arrays 6-7 nm in unit cell dimension. The apposing concave membrane of the junction displayed fracture faces without intramembrane particles or pits. Therefore, wavy junctions are asymmetric structures composed of MIP crystals abutted against particle-free membranes. In thin junctions, anti-MIP labeled the cytoplasmic surfaces of both apposing membranes with varying degrees of asymmetry. In thin junctions, MIP was found organized in both small clusters and single membranes. These small clusters also abut against particle-free apposing membranes, probably in a staggered or checkerboard pattern. Thus, the structure of thin and wavy junctions differed only in the extent of crystallization of MIP, a property that can explain why this protein can produce two different antibody-labeling patterns. A conclusion of this study is that wavy and thin junctions do not contain coaxially aligned channels, and, in these junctions, MIP is unlikely to form gap junction-like channels. We suggest MIP may behave as an intercellular adhesion protein which can also act as a volume-regulating channel to collapse the lens extracellular space. Junctions constructed of MP70 have a wider overall thickness (18-20 nm) and are abundant in the cortical regions of the lens. A monoclonal antibody raised against this protein labeled these thicker junctions on the cytoplasmic surfaces of both apposing membranes. Thick junctions also contained isolated clusters of MIP inside the plaques of MP70. The role of thick junctions in lens physiology remains to be determined

Serological Survey Of Salmonella gallinarum Antibody In Chickens Around Jos, Plateau State, Nigeria

A serological survey of the prevalence of antibodies to Salmonella gallinarum among chickens under two different management systems around Jos, Plateau State, Nigeria was carried out using the standard plate agglutination test. The objective of this study was to determine serologically the prevalence of antibodies against Salmonella gallinarum among apparently healthy chickens around Jos. A total of 700 serum samples made up of 450 exotic and 250 local breed of chickens were used for this study with 37.9% seropositvity. In the free range system (19.3%) of the flocks sampled were seropositive for Salmonella gallinarium antibodies while in the semi intensive, 18.6% of the flock tested positive. The serum agglutination test (SAT) was adapted to the microtitre format used to determine somatic and flagella titres. The antigen used for this study was specific for S. gallinarum, hence differentiation between species infection was assessed in this study. Perhaps the most feasible way to eradicate the disease is to encourage farmers (both small and large scale) to break the disease cycle at their levels by embarking on prompt and regular vaccination programmes. It is thus concluded that Salmonella gallinarum (fowl typhoid) is present in the area investigated. Fowl typhoid may continue to have a negative effect on the economy of poultry production in Nigeria if not controlled. A statistical analysis was precluded due to inadequate data sets

Antibiotic like-substances produced by some trichophytic dermatophytes

Antibiotic production by dermatophytic fungi was demonstrated. Among 10 anthropophilic dermatophytes strains tested for their ability to produce antibiotics, four were found to be producers. The outcome for a qualitative identification of the produced antibiotics reveals four types ; a penicillin-like substance produced by Trichophyton gourvillii, and two different types of unknown substances obtained from two strains of Trichophyton mentagrophytes var. interdigitales and the kojic acid-like antibiotic substance produced by Trichophyton verruccosum

Are there hopeless neighborhoods? An exploration of environmental associations between individual-level feelings of hopelessness and neighborhood characteristics

http://deepblue.lib.umich.edu/bitstream/2027.42/109742/1/Are there hopeless .pd

Amino acid analysis and biological evaluation of detoxified Thevetia seed meal

Thevetia peruviana seed meal was detoxified using two methods – acid hydrolysis followed by ethanolic extraction of the released aglycones and direct ethanolic extraction of the cardiac glycosides. Acid detoxification followed by alcoholic extraction of the aglycones gave a meal with 95% reduction in the glycoside content (from 42.7 to 2.15 g kg-1), while direct alcohol detoxification led to a 98% reduction in the glycoside content of the seed meal (from 42.7 to 0.83 g kg-1). The two treated Thevetia seed meals (TSM) were used to formulate poultry diets by introducing 0, 5, 10 and 15% of treated TSM into the feed composition which is equivalent to 0, 16.7, 33.3 and 50% replacement of soybean meal. The results showed that up to 15 % inclusion of alcohol detoxified TSM (≈ 50% replacement of soybean meal) produced no mortality and gave satisfactory growth performance of the cockerels used for the experiment. The performance of birds on alcohol detoxified diets was comparable with that of birds on the control diet. However, diets formulated with acid detoxified TSM gave fairly satisfactory performance only with 5% inclusion of the detoxified meal in the diet (i.e., 16.7 % replacement of soybean in the meal). Higher inclusion levels (5 and 10% inclusions) resulted in reduced feed intake and retention, reduced activity and high mortality (25 – 33% mortality). The birds were uncoordinated, walked limply and generally exhibited poor growth performance. Amino acid analysis of the detoxified TSM also showed that the alcohol-detoxified meal had a better amino acid profile and higher essential amino acid contents than either the raw meal or the acid-detoxified meal. The acid-detoxified meal had the lowest content of all amino acids analyzed except the acid amino acids which were increased. Generally, alcohol detoxification appeared to be the best and most effective of the two detoxification methods examined

Community awareness of bird flu and the practice of backyard poultry in a North-Central State of Nigeria

Introduction. The practice of backyard poultry is a very common practice in many homes in Nigeria. Birds raised at home are usually free ranged, which increases close contact between man and birds, thus increasing the risk of transmission of avian influenza virus to man. This study investigated the awareness of bird flu infection and identifies risk factors associated with the practice of backyard/free ranged poultry among the residents of a state in Northern Nigeria. Methods. This cross-sectional study was carried out in Kwara State using 130 wards selected through cluster sampling technique. Households in each ward were sampled through systematic random sampling technique using the primary health care house numbering register. Semi-structured questionnaire was used to generate relevant information through interview and 650 participants consented and were used for the study. Results. Most of the respondents 604 (92.9%) kept birds in their homes and one-third 204 (33.8%) of this group knew that infection from birds can be transmitted to man. However, less than a third186 (30.8%) of those who keep birds were aware of avian influenza (AI) infection. Out of the 186 respondents, 78 (41.9%) had experienced massive bird deaths in the preceding year prior to the interview. Less than half 81 (43.5%) were willing to report AI or massive deaths occurring in flocks of their birds to designated officers / authority. During outbreaks with massive deaths in birds some of the respondents sold infected live birds 45 (57.7%), few slaughtered and dressed the birds before sale 11 (14.1%), while some slaughtered and consumed the birds in their families 19 (24.4%). Conclusion. The practice of backyard poultry is very high with little knowledge and awareness of mechanism and risk of infection associated with it. This was also reflected in their attitude towards reporting of outbreaks in birds. Public awareness campaign and home visit by environmental and veterinary officers are important strategies that can prevent AI infection transmission among domestic birds and man

Traditional exploitation of edible freshwater oyster Etheria elliptica (Lamarck, 1807) in Pendjari River (Benin-West Africa): assessment of income, human pressure and options for management

Freshwater oyster Etheria elliptica (Mollusca: Bivalvia) was harvested in Pendjari River as important source of protein and income. The river crosses the Pendjari Biosphere Reserve, a protected area in Northern Benin. The freshwater oyster is harvested outside and within the protected area with increasing human pressure. The current study aims at assessing fishery production, human impact on wild stocks and suggests sustainable management options. Individual semi-structured interviews and monitoring of oyster collection were used to collect data on harvesters’ socio-economic characteristics, biomass production and seasonal income in 2008 and 2009. Mean shell size and weight as well as size frequency distribution were analyzed in relation to harvesting pressure. Oyster harvesting is the main traditional activity of Berba women in dry season, at low water level period. The oyster collectors used artisanal tools such as chisel-like metal, stone-hammer, rope, metal pan and pot. Biomass production, oysters mean size and weight decreased from protected sites to unprotected zones revealing negative anthropogenic pressure on oyster natural stocks. Size frequency distribution displayed an important proportion of smaller individuals in open access sites whilst larger size oysters were more encountered in protected zones. Therefore, exploitation appeared likely as a potential threat for oyster bed. Moreover, the oyster collectors not only exploited individuals without observing a minimum limit size, but they also targeted each year the same sites regardless rotation planning. Finally, oyster`s shell, a main substrate for larval settlement and bed restoration, were left on riverbanks after exploitation, reducing stocks reconstitution potential. Appropriate measures were suggested to Reserve staff for sustainable management.Keywords: Freshwater mollusk, harvesting activities, human pressure, fisheries management

Nanosilver and the microbiological activity of the particulate solids versus the leached soluble silver.

Nanosilver (Ag NPs) is currently one of the most commercialized antimicrobial nanoparticles with as yet, still unresolved cytotoxicity origins. To date, research efforts have mostly described the antimicrobial contribution from the leaching of soluble silver, while the undissolved solid Ag particulates are often considered as being microbiologically inert, serving only as source of the cytotoxic Ag ions. Here, we show the rapid stimulation of lethal cellular oxidative stress in bacteria by the presence of the undissolved Ag particulates. The cytotoxicity characteristics are distinct from those arising from the leached soluble Ag, the latter being locked in organic complexes. The work also highlights the unique oxidative stress-independent bacterial toxicity of silver salt. Taken together, the findings advocate that future enquiries on the antimicrobial potency and also importantly, the environmental and clinical impact of Ag NPs use, should pay attention to the potential bacterial toxicological responses to the undissolved Ag particulates, rather than just to the leaching of soluble silver. The findings also put into question the common use of silver salt as model material for evaluating bacterial toxicity of Ag NPs

Detection of African swine fever virus (ASFV) antibodies in pigs in Taraba state north east Nigeria

A serological study was conducted between 2011 and 2013 to detect the presence of antibodies to African swine fever virus (ASFV) in Pigs in Taraba State, north eastern Nigeria. Sixty (60) pig farms were studied. Questionnaires (N=885) consisting of sections related to the farmer and the animal were distributed and blood samples taken to analyze for the African swine fever virus antibodies. All the 60 questionnaires were answered by the farmers, while 885 were retrieved for the individual pig studied. Of the 60 famers, only 13 (21.7%) were aware of the disease while 47 (78.3%) were ignorant (P<0.05). Out of the 885 pigs examined, none (0%) was infected nor showed any clinical signs of the infection. However, 117 (13.2%) out of the 885 sera samples analyzed for the three year period were positive for ASFV antibodies. The results obtained in 2013 (22.5%) was significantly higher (P<0.05) those in 2011 (12.9%) and 2012 (4.0%). Although male pigs recorded higher sero-prevalence (13.7%) than the females (12.9%), this was no statistically significant (P>0.05). The highest sero-prevalence (16.3%) was  recorded in the Northern zone in 2011, followed by 10.0% and 5.0% in Southern and Central zones  respectively. In the year 2012, no ASFV antibody was detected from the 100 and 99 pigs examined from Central and Northern zones respectively. However, the Central zone recorded a sero-prevalence of  12.0%. In 2013, the sero-prevalence in Southern (29.0%) and Central zones (24.0%) is significantly higher (P<0.05) than in the Northern zone. The sero-prevalence obtained may pose a great risk in the study area, it is therefore recommended that adequate veterinary services, proper sanitary measures and monitoring of pig movement be instituted to avert an outbreaks.Keywords: African swine fever virus, Antibodies, ELISA, Pigs, Taraba State, North eastern Nigeri