Lack of insulin stimulation on Percoll-prepared or high-speed-centrifuged rat liver hepatocytes

Rat liver hepatocytes isolated from a 30-31% percoll density gradient at 10,000g are refractory toward insulin stimulation of 14CO2 formation and 14C-incorporation into protein from [2,3-14C]succinate. Basal hepatocyte oxidation of succinate was not impaired by the presence of 5% percoll in the incubation medium nor was it impaired when percoll-free hepatocytes were used that had been isolated after centrifugation at 9000g; however, in both instances the stimulatory effect of insulin was lost. Hepatocyte damage may have occurred in these processes. This is in contrast to previous work which shows that insulin (10 mU/ml) will stimulate [2,3-14C]succinate oxidation and [2,3-14C]succinate carbon incorporation into protein in non-percoll-treated hepatocytes (isolated by centrifugation at 10g) by about 29%. We conclude that the latter procedure although more time consuming is the more gentle method of choice and leaves the hepatocyte in a form more closely related to an in vivo state than does treatment with a percoll density gradient at 10,000g.     

Isolation and characterization of acetonitrile utilizing bacteria

Summary Bacteria utilizing high concentrations of acetonitrile as the sole carbon source were isolated and identified asChromobacterium sp. andPseudomonas aeruginosa. Maximum growth was attained after 96 h of incubation andP. aeruginosa grew slightly faster thanChromobacterium sp. The strains were able to grow and oxidize acetonitrile at concentrations as high as 600 mM. However, higher concentrations inhibited growth and oxygen uptake. Degradation studies with (¹⁴C)acetonitrile indicated 57% of acetonitrile was degraded byPseudomonas aeruginosa as compared to 43% byChromobacterium. The isolates utilized different nitrile compounds as carbon substrates.     

Breeding soundness examinations of rams and bucks, a review

Breeding soundness examinations of rams and bucks may be performed by veterinarians as a service for clients. A physical examination for breeding soudness includes a general examination for health with special consideration of the reproductive organs. Careful examination of the penis, prepuce, and testicles may reveal diseases or abnormalities which decrease reproductive potential. Rams with small or hypoplastic testicles are unsatisfactory potential breeders as testicle size is positively related to sperm production. Libido may be assessed during semen collection procedures or from observations of the owner. Semen quality may be evaluated using tests for motility, concentration, and morphology of spermatozoa. Rams may be declared satisfactory, questionable, or unsatisfactory potential breeders as a result of the examination.     

Amphibolic role of the Krebs cycle in the insulin-stimulated protein synthesis.

It has been a generally held view that insulin does not significantly affect the incorporation of amino acids into liver protein. This interpretation was based on data obtained from studies using the branched chain amino acids, which are poorly metabolized by the hepatic tissue. The effect of insulin on 14CO2 formation and protein incorporation of several 1-14C-labeled or U-14C-labeled amino acids was studied in isolated rat hepatocytes and diaphragm pieces. It was shown that insulin enhanced 14CO2 formation and protein incorporation primarily of those carbons of amino acids which are metabolized through the mitochondrial Krebs cycle. Using aminooxyacetic acid (0.5 mM), a potent inhibitor of the transamination reaction, it was shown that there exists an "insulin-sensitive" pool of glutamate which is preferentially utilized for protein synthesis in the presence of insulin. The insulin effect on protein incorporation of 14C-labeled glutamate generated in the Krebs cycle was abolished in the presence of aminooxyacetic acid. We interpret these results to signify that mitochondrial transamination of alpha-ketoglutarate to glutamate is essential for insulin stimulation of 14C incorporation into hepatocyte protein.     

Molecular characterization of Plasmodium vivax clinical isolates in Pakistan and Iran using pvmsp-1, pvmsp-3α and pvcsp genes as molecular markers

In this study, the diversity of Plasmodium vivax populations circulating in Pakistan and Iran has been investigated by using circumsporozoite protein (csp) and merozoite surface proteins 1 and 3α (msp-1 and msp-3α) genes as genetic markers. Infected P. vivax blood samples were collected from Pakistan (n = 187) and Iran (n = 150) during April to October 2008, and were analyzed using nested-PCR/RFLP and sequencing methods. Genotyping pvmsp-1 (variable block 5) revealed the presence of type 1, type 2 and recombinant type 3 allelic variants, with type 1 predominant, in both study areas. The sequence analysis of 33 P. vivax isolates from Pakistan and 30 from Iran identified 16 distinct alleles each, with one allele (R-8) from Iran which was not reported previously. Genotyping pvcsp gene also showed that VK210 type is predominant in both countries. Moreover, based on the size of amplified fragment of pvmsp-3α, three major types: type A (1800 bp), type B (1500 bp) and type C (1200 bp), were distinguished among the examined isolates that type A was predominant among Pakistani (72.7%) and Iranian (77.3%) parasites. PCR/RFLP products of pvmsp-3α with HhaI and AluI have detected 40 and 39 distinct variants among Pakistani and Iranian examined isolates, respectively. Based on these three studied genes, the rate of combined multiple genotypes were 30% and 24.6% for Pakistani and Iranian P. vivax isolates, respectively. These results indicate an extensive diversity in the P. vivax populations in both studies.     

Reunderstanding Cairo through urban metabolism: Formal versus informal districts resource flow performance in fast urbanizing cities

Urban expansion can be seen as the most pervasive human impact on the environment where its high resource use contributes negatively to climate change and resource scarcity crises. Many experts call for decoupling resource use, economic development, and related urban development especially within cities of the Global South. This paper focuses on investigating resource efficiency through the lens of urban metabolism. It investigates current resource flows, through material flow analysis, from source to sink, in two diverse districts in Cairo: a formal district and an informal one, regarding materials (waste) and mobility. Consequently, the paper discusses locally responsive interventions that address local priorities as opposing to citywide one‐size fits all solution. The paper relies on parcel audits, which are embedded in an Urban Metabolism Information System developed by the Ecocity Builders and their partners, through a joint project with Cairo University. The methodology couples crowd‐sourced data, parcel audits, and experts’ knowledge to better understand resource flows based on a bottom‐up approach, given the unavailability of governmental data on the local level. The paper further correlates the perceived quality of life with the actual resource flows. It utilizes fieldwork investigations to argue against the local misconceptions regarding the inefficiency of informal areas/systems versus the higher efficiency of planned areas/systems. The paper concludes by proposing integrated solutions that respond to local needs and resources. It highlights the challenges and lessons of this tailored bottom‐up approach and its applicability in other cities worldwide.     

In silico annotation of unreviewed acetylcholinesterase (AChE) in some lepidopteran insect pest species reveals the causes of insecticide resistance

Lepidoptera is the second most diverse insect order outnumbered only by the Coeleptera. Acetylcholinesterase (AChE) is the major target site for insecticides. Extensive use of insecticides, to inhibit the function of this enzyme, have resulted in the development of insecticide resistance. Complete knowledge of the target proteins is very important to know the cause of resistance. Computational annotation of insect acetylcholinesterase can be helpful for the characterization of this important protein. Acetylcholinesterase of fourteen lepidopteran insect pest species was annotated by using different bioinformatics tools. AChE in all the species was hydrophilic and thermostable. All the species showed lower values for instability index except L. orbonalis, S. exigua and T. absoluta. Highest percentage of Arg, Asp, Asn, Gln and Cys were recorded in P. rapae. High percentage of Cys and Gln might be reason for insecticide resistance development in P. rapae. Phylogenetic analysis revealed the AChE in T. absoluta, L. orbonalis and S. exigua are closely related and emerged from same primary branch. Three functional motifs were predicted in eleven species while only two were found in L. orbonalis, S. exigua and T. absoluta. AChE in eleven species followed secretory pathway and have signal peptides. No signal peptides were predicted for S. exigua, L. orbonalis and T. absoluta and follow non secretory pathway. Arginine methylation and cysteine palmotylation was found in all species except S. exigua, L. orbonalis and T. absoluta. Glycosylphosphatidylinositol (GPI) anchor was predicted in only nine species.