Effect of papaya (Carica papaya) leaf extract as dietary growth promoter supplement in red hybrid tilapia (Oreochromis mossambicus × Oreochromis niloticus) diet

The purpose of this experiment was to examine the potential use of Carica papaya leaf extract as a supplement to promote growth and improve feed utilization in red hybrid tilapia. Five diets were formulated containing isolipidic (80 g/kg) and isonitrogenic (350 g/kg) levels. All feeds contained similar types and amounts of raw materials but differed in the inclusion of papaya leaf extract (0, 5, 10, 20 and 40 g/kg feed). The initial size of fish used was 2.3 ± 0.01 g. Each diet was performed in triplicate tanks, and the feeding period was 12 weeks. Fish fed diet containing 2% papaya leaf extract (PLE) had the highest final weight, 31.14 ± 1.47 g, followed by 1% PLE (27.27 ± 1.75 g). These two diets (1% and 2%) were also showed significant improvements of weight gain, SGR, and feed efficiency of the red hybrid tilapia (p < 0.05). However, papaya leaf extract did not affect the HSI, VSI, PER, digestive enzymes activity, blood composition, and survival rate. Supplementing the diets with papaya leaf extract lowered serum urea. Findings of this research suggest that adding papaya leaf extract to the diet of red hybrid tilapia improves growth and feed efficiency without adversely affecting blood parameters. Therefore, an inclusion level between 1% and 2% of the papaya leaf extract is recommended as a feed additive to promote red hybrid tilapia fry growth.     

Classification of hybrid and altered Vibrio cholerae strains by CTX prophage and RS1 element structure

Analysis of the CTX prophage and RS1 element in hybrid and altered Vibrio cholera O1 strains showed two classifiable groups. Group I strains contain a tandem repeat of classical CTX prophage on the small chromosome. Strains in this group either contain no element(s) or an additional CTX prophage or RS1 element(s) on the large chromosome. Group II strains harbor RS1 and CTX prophage, which has an E1 Tor type rstR and classical ctxB on the large chromosome.     

Cdc5 influences phosphorylation of Net1 and disassembly of the RENT complex

Background  

In S. cerevisiae, the mitotic exit network (MEN) proteins, including the Polo-like protein kinase Cdc5 and the protein phosphatase Cdc14, are required for exit from mitosis. In pre-anaphase cells, Cdc14 is sequestered to the nucleolus by Net1 as a part of the RENT complex. When cells are primed to exit mitosis, the RENT complex is disassembled and Cdc14 is released from the nucleolus.     

Unmet need for additional medical care for sick children in mother's view in rural Bangladesh: implications for improving child health services

While a country's health policy aims to provide health services to all who need them, very little in known about unmet need for additional medical care from users' perspectives in Bangladesh. This study examined unmet medical need (defined as whether a mother felt that, to manage sickness, her child had required medical care that was not available, regardless of reasons and medical care sought) of 2123 under-15 sick children by illness and child's socioeconomic characteristics in rural Bangladesh. The 1996 Health and Socioeconomic Survey conducted in Matlab recorded children's chronic (a disease or a condition lasting 3 months or more) and acute (a disease or a condition with a rapid onset and a short, severe course) morbidity, medical care sought to combat illness and unmet needs for additional medical services in mothers' views to manage the illness. The survey also recorded household socioeconomic data. Logistic regression was used to examine the data. The results reveal that unmet needs for additional medical care were 5.4% for children with acute illnesses, and 30.2% for children with chronic illnesses. For chronic illnesses, seeking medical care to manage illness from any health provider outside the home reduced unmet medical needs. Economic inequalities existed for both acute and chronic illnesses: the odds ratio of unmet medical needs for sick children of the least poor households was 0.42 (95% CI: 0.28-0.64) times that for sick children of the very poor households. The critically high unmet needs for children's chronic morbidity reveal that the chronic disease control programme in Bangladesh needs urgent revisiting and strengthening.     

Analysis of Antarctic proteobacteria by PCR fingerprinting and screening for antimicrobial secondary metabolites

Fifty-seven proteobacterium species were successfully isolated from soils of Barrientos Island of the Antarctic using 11 different isolation media. Analysis of 16S rDNA sequencing of these isolates showed that they belonged to eight different genera, namely Bradyrhizobium, Sphingomonas, Methylobacterium, Caulobacter, Paracoccus, Ralstonia, Rhizobium, and Staphylococcus. All isolates were studied for capability of producing antimicrobial and antifungal secondary metabolites using high-throughput screening models. Approximately 23 (13/57) and 2% (1/57) of isolates inhibited growth of Candida albicans ATCC 10231(T) and Staphylococcus aureus ATCC 51650(T), respectively. These results indicated that proteobacterium species isolates from Antarctic could serve as potential source of useful bioactive metabolites. Enterobacterial repetitive intergenic consensus (ERIC)-PCR fingerprinting produced nine clusters and 13 single isolates, with a high D value of 0.9248. RAPD fingerprinting produced six clusters and 13 single isolates, with a relatively low D value of 0.7776. ERIC-PCR analysis proved to have better discrimination capability than RAPD analysis and generated better clustering for all proteobacterium species isolates. We conclude that ERIC-PCR is a robust, reliable and rapid molecular typing method for discriminating different genera of proteobacteria.     

Individual admixture estimates: disease associations and individual risk of diabetes and gallbladder disease among Mexican-Americans in Starr County, Texas

The ethnic and geographic distributions of several common chronic diseases show distinct patterns that are consistent with the distribution of genes and genetic admixture. For example, diabetes and gallbladder disease occur most frequently among Amerindians, while those genetically admixed with them (such as Mexican-Americans) have intermediate rates, and lowest rates are found among Whites and Blacks. Because there will be heterogeneity from individual to individual in ancestral affinity within an admixed population, a method is developed for estimating each person's admixture probability. Results confirm that there is substantial heterogeneity of individual admixture among Mexican-Americans in Starr County, Texas, with a mean value indicating that 65% of genes in this population are Caucasian derived and 35% Amerindian derived. The individual estimates are shown to be unrelated to the probability of being diabetic and only marginally related to gallbladder disease, with those having the most Amerindian affinity being at increased risk. These results are a consequence of the independent assortment of loci and indicate that unless the markers employed are related (including linkage) to the disease of interest, the method will have limited utility. Individual admixture estimates will be useful, however, for examining aspects of population structure and will find increased utility for predicting disease and examining disease associations as more and more of the genome is represented by markers, a very probable prospect with the abundance of DNA polymorphism being identified by restriction enzymes.     

Conformational stabilization at the active site of molluskan (Rapana thomasiana) hemocyanin by a cysteine-histidine thioether bridge A study by mass spectrometry and molecular modeling

In some type-3 copper proteins (molluskan hemocyanin, catechol oxidase and fungal tyrosinase) one of the histidine residues, liganding the Cu(A) atom of the dinuclear copper active site, is covalently linked to a cysteine residue by a thioether bridge. The purpose of this study was to disclose the function of this bridge. Mass spectral analysis of a peptide, isolated from Rapana thomasiana (gastropodan mollusk) hemocyanin, indicated a stabilization of the peptide structure in the region of the bridge. Molecular modeling of three thioether containing type-3 copper proteins using the dead-end elimination method showed that the concerned histidine would be very flexible if not linked to the cysteine. Also, the side chain orientation of the histidine is rather exceptional, as evidenced by statistical data from the protein databank. It is suggested that the role of the bridge is to fix the histidine in an orientation that is optimal for coordination of the Cu(A) atom.     

Influence of limited proteolysis,detergent treatment and lyophilization on the phenoloxidase activity of Rapana thomasiana hemocyanin

The intrinsic and inducible phenoloxidase (PO) activity of Rapana thomasiana hemocyanin (RtH) and its substructures were studied. With catechol as substrate, a weak o-diPO activity was measured for the didecameric RtH and its subunits. Some activation of the o-diPO activity of RtH was achieved by limited treatment with subtilisin and by incubation of RtH with 2.9 mM sodium dodecyl sulphate (SDS), suggesting an enhanced substrate access to the active sites. The highest artificial induction of o-diPO activity in RtH, however, was obtained by lyophilization of the protein. This is ascribed to conformational changes during the lyophilization process of the didecameric RtH molecules, affecting the accessibility of the active sites. These conformational changes must be very small, since Fourier-transform infrared and circular dichroism spectroscopies did not reveal any changes in secondary structure of lyophilized RtH. The difference in accessibility of the copper containing active site for substrates between catechol oxidase and functional unit RtH2-e was demonstrated by molecular modeling and surface area accessibility calculations. The low level of intrinsic PO activity in the investigated hemocyanin is related to the inaccessibility of the binuclear copper active sites to the substrates.