The isolation and possible significance of some toxic mammalian metabolites of diazinon

The recognition and isolation of toxic metabolites of diazinon by gas, thin-layer, column and high-pressure liquid chromatography is discussed. The possible toxicological significance of these compounds is considered and some preliminary attempts to assess their importance by experiments with microsomal preparations are mentioned.     

Acoustic evaluation of loblolly pine tree- and lumber-length logs allows for segregation of lumber modulus of elasticity,not for modulus of rupture

Key message

Loblolly pine ( Pinus taeda ) logs can be evaluated using acoustic velocity whereby threshold acoustic velocity values can be set to ensure lumber meets specified mechanical property design values for modulus of elasticity.

Context

There is a need to better sort logs according to lumber quality for improved decision making and wood utilization because merchantable logs are being harvested from different stand types including natural forests, conventional plantations, and intensively managed plantations, all with differences in rotation ages, growth rates, and wood quality traits.

Aims

This study aimed to link tree- and lumber-length log acoustic velocity with the resulting lumber properties as tested in static bending from five intensively managed loblolly pine stands in the Atlantic Coastal Plain of Georgia.

Methods

Acoustic velocity was measured using the resonance-based approach on 87 tree-length logs and 244 lumber-length logs. The logs were then processed into 797 pieces of 38 mm by 89 mm (2×4), 140 mm (2×6), 184 mm (2×8), and 235 mm (2×10) dimension lumber, dried, and tested in static bending.

Results

Mean MOE of the lumber had moderate relationships with acoustic velocity of the logs (R ² = 0.49) whereas MOR and acoustic velocity did not have a strong relationship (R ² = 0.20). Accounting for log position increased the performance of the mean lumber MOE model (R ² = 0.62) which was further increased by adding green density and small-end diameter (R ² = 0.67). Utilization of acoustics was effective for segregating logs based on lumber modulus of elasticity and did not depend on knowing tree or stand information such as age, site quality, and silviculture history.

Conclusion

Acoustic velocity evaluation of tree- and lumber-length logs could be employed to segregate logs within the supply chain to ensure that lumber would meet specified design values.

     

On the occurrence,distribution and taxonomy of <Emphasis Type="Italic">Momordica subangulata</Emphasis> Blume subsp. <Emphasis Type="Italic">renigera</Emphasis> (G. Don) de Wilde in India

Different authors in India and South East Asia treat dioecious species in the genus Momordica differently. The cultivated ‘bhat karela’ of East and North East India is referred to as Momordica dioica Roxb. by botanists and herbarium curators whereas agricultural scientists, in general, designate it as Momordica cochinchinensis Spreng. A critical study of 266 herbarium sheets housed at CAL and BSISH and in situ field studies at specific pockets in the North East India followed by preliminary characterization revealed its correct identity as Momordica subangulata Blume subsp. renigera (G. Don) de Wilde. First hand information on its occurrence, taxonomy and distribution in India is given. The species was found in wild as well as in homestead cultivation in North Eastern India and exemplify direct utilization of biodiversity by indigenous people.

Checking that replication breakdown is not terminal

Two new studies help to clarify the relationship between checkpoint proteins, recombination, and replication fork integrity.     

Tissue-specific and developmental modifications of grape cell walls influence the adsorption of proanthocyanidins

Cell wall material from Vitis vinifera L. cv. Cabernet Sauvignon grape skin and flesh was isolated at different stages of grape maturity to determine whether developmental changes in cell wall composition in different tissue types influence the binding of proanthocyanidins (PAs). Trends in cell wall adsorption of, and selectivity for, PAs were determined using two skin PAs that differed in their average molecular masses. Flesh cell walls consistently bound a higher amount of PA than those from skin. Key structural differences that reduced PA adsorption in skin cell walls by comparison with flesh cell walls were endogenously higher concentrations of insoluble PA, Klason lignin, and lower cell wall-bound protein. These differences may confer reduced flexibility and porosity of skin cell walls relative to flesh cell walls. Analysis of skin and flesh cell wall properties revealed that the onset of ripening was associated with a loss of type I arabinogalactan and galacturonic acid, which indicated a degradation of pectin within the cell wall. Flesh cell walls consistently bound PAs of larger molecular mass, and changes in PA adsorption properties after the onset of ripening were minor. For skin cell walls, adsorption of PA was lowest immediately following solubilization of galacturonic acid, and high molecular mass PAs were poorly bound. As ripening progressed, PAs of higher molecular mass were selectively adsorbed by skin cell walls, which indicates that ongoing cell wall remodeling during ripening may confer an increased porosity within the skin cell wall matrix, resulting in a greater adsorption of PA within a permeable structure.     

Quantifying dietary phosphorus requirement of fish – a meta‐analytic approach

A meta‐analysis of available data on dose response to dietary phosphorus (P) in fish from over 70 feeding trials reported in 64 published studies covering over 40 species of fish was performed. Broken‐line regression was used to model the data sets. The meta‐analysis showed that estimated minimal dietary P level varies with the response criterion and that estimates should preferably be expressed in terms of available P than in terms of total P. Estimates based on whole‐body P concentration (4.7 g available P kg^?1 dry matter, DM) or vertebral P (5.2 g available P kg^?1 DM) were greater than that for maximizing somatic weight gain (WG) (3.5 g available P kg^?1 DM) or plasma P concentration (2.8 g available P kg^?1 DM). P content of fish varies linearly with body mass (3.6 g kg^?1 live weight). Use of ingredients rich in P or of diets with high basal P content or high levels of water P concentration can affect the estimations. Among the different response criteria tested, WG was found to be the most reliable and whole‐body P concentration to be the most stringent criterion to estimate P requirement of a given fish species. Expressing available P requirement as g P per unit DM or digestible energy (DE) in the diet was equally effective, but expressing in terms of g P intake per kg BW^0.8 per day would be more precise.     

Dietary micronutrient composition affects fillet texture and muscle cell size in Atlantic salmon (Salmo salar)

During the past 20 years, plant ingredients have taken over as the main constituents in feed for Atlantic salmon. This has changed the nutrient composition of the feeds, the bioavailability of nutrients and perhaps nutrient metabolism. Plant‐based diets also contain more anti‐nutrients. The EU‐funded project ARRAINA re‐evaluated recommendations for micronutrient supplementation to Atlantic salmon feeds, and the present study compared a diet supplemented with micronutrients according to NRC (2011) (control diet, 100% NP (nutrient package)) with a diet supplemented according to the new recommendations (New NP). Tissue concentrations of pyridoxine, pantothenic acid, niacin, vitamin C, Zn and Se were significantly higher; and Cu was lower in Atlantic salmon fed the diet with the New NP compared to the control fish. The New NP also gave a near significant effect on growth, decreased muscle firmness and increased muscle cell size, and it affected metabolism of nitrogen‐containing metabolites in the muscle. While we cannot be certain which micronutrient(s) gave these effects, the B vitamins are probable candidates, since they are mediators of intermediary metabolism and have been shown to influence some of the affected metabolites.     

Cisplatin and doxorubicin toxicosis in dogs with osteosarcoma

Toxicosis associated with doxorubicin and cisplatin administration starting either 2 or 10 days after limb amputation for osteosarcoma was examined retrospectively in dogs. The purpose was to determine whether dosage and timing of chemotherapy affected rates of toxicosis after administration of the 1st treatment. Records of 100 dogs with appendicular osteosarcoma without evidence of metastases or concurrent disease were examined. Dogs received chemotherapy with doxorubicin and cisplatin every 3 weeks for 3 treatments starting 2 days (n = 51) or 10 days (n = 49) after amputation. The dosage of cisplatin was 60 mg/m2 and was given with 6-hour saline diuresis and butorphanol. Doxorubicin was given at 12.5-25 mg/ml during fluid administration. Hematologic data were collected before and weekly after treatment. Client interviews were conducted to assess gastrointestinal toxicosis during the interval between treatments. The reported toxicoses were graded on a scale of 0 to 4. Dogs receiving 25 mg/m2 of doxorubicin experienced greater rates of grade 4 toxicity (67%; n = 6) than dogs in groups receiving 12.5-20 mg/m2 of doxorubicin (< or = 25%; n = 94, P = .03). Dogs in the Day 2 group experienced greater rates (35%) of grade 4 toxicity than dogs in the Day 10 group (12%, P = .007). We concluded that chemotherapy administered 2 days after surgery produced an unacceptable level of toxicoses. except at greatly reduced dosages, and that even with a delay of treatment, 25 mg/m2 of doxorubicin, when given in combination with cisplatin at 60 mg/m2, was too toxic for routine use.