Conformational and intramolecular hydrogen bonding effects on post-emergence and pre-emergence selectivities of herbicidal pyrrole dicarboxylates

Dimethyl 2-methyl-5-(chloropyridin-2-yl)pyrrole-3,4-dicarboxylates in which the chlorine atom is substituted at different positions of the pyridine ring have widely varying biological properties. The 3-chloro analog (I) is a post-emergence and pre-emergence herbicide, the 4- and 5-chloro analogs (II, III) are post-emergence herbicides but not pre-emergence, and the 6-chloro analog (IV) is inactive. Computer graphic and molecular mechanics analyses of their molecular conformations showed that the 4- and 5-chloro analogs adopt a coplanar, intramolecularly hydrogen bonded conformation whereas the 3-chloro analog does not. High-level quantum mechanical calculations of the conformational preferences of related model systems were in agreement with these results. Based on this, II and III were predicted to have higher octanol/water partition coefficients relative to I, leading to higher soil binding and weaker xylem transport, hence their observed weaker pre-emergence activities. Experimental measurements of octanol/water partition coefficients, soil binding, and infrared hydrogen bonding studies verified these predictions. Molecular modeling techniques are usually used for designing compounds to fit enzyme active sites and designing putative receptor models. This study demonstrates the usefulness of these techniques for dealing with transport problems.     

Epidemiology, disease and control of infections in ruminants by herpesviruses--an overview

There are at least 16 recognised herpesviruses that naturally infect cattle, sheep, goats and various species of deer and antelopes. Six of the viruses are recognised as distinct alphaherpesviruses and 9 as gammaherpesviruses. Buffalo herpesvirus (BflHV) and ovine herpesvirus-1 (OvHV-1) remain officially unclassified. The prevalence of ruminant herpesviruses varies from worldwide to geographically restricted in distribution. Viruses in both subfamilies Alphaherpesvirinae and Gammaherpesvirinae cause mild to moderate and severe disease in respective natural or secondary ruminant hosts. Accordingly, the economic and ecological impact of the viruses is also variable. The molecular characteristics of some members have been investigated in detail. This has led to the identification of virulence-associated genes and construction of deletion mutants and recombinant viruses. Some of the latter have been developed as commercial vaccines. This paper aims to give an overview of the epidemiology and pathogenesis of infection by these viruses, immuno-prophylaxis and mechanisms of recovery from infection. Since there are 128 ruminant species in the family Bovidae, it is likely that some herpesviruses remain undiscovered. We conclude that currently known ruminant alphaherpesviruses occur only in their natural hosts and do not cross stably into other ruminant species. By contrast, gammaherpesviruses have a much broader host range as evidenced by the fact that antibodies reactive to alcelaphine herpesvirus type 1 have been detected in 4 subfamilies in the family Bovidae, namely Alcelaphinae, Hippotraginae, Ovibovinae and Caprinae. New gammaherpesviruses within these subfamilies are likely to be discovered in the future.     

A multi-state Salmonella Typhimurium outbreak associated with frozen vacuum-packed rodents used to feed snakes

From December 2005 through January 2006, the Minnesota Department of Health (MDH) identified four human clinical isolates of Salmonella Typhimurium that were indistinguishable by pulsed-field gel electrophoresis (PFGE). During routine interviews, three of the cases reported attending the same junior high school and two handled snakes in the science classroom. MDH collected environmental samples from the school's science classroom for Salmonella culturing; these included environmental samples and frozen vacuum-packed mice purchased over the internet to feed the classroom snakes. Through PulseNet, a national molecular subtyping surveillance network for enteric bacteria, 21 human S. Typhimurium isolates with indistinguishable PFGE patterns were identified in the United States since December 2005. Each state determined whether these human cases had recent exposure to snakes fed vacuum-packed rodents. Texas state officials conducted tracebacks of the vacuum-packed mice and collected samples at the breeding facility. Nineteen of 21 cases were interviewed, and seven reported contact with frozen vacuum-packed rodents from the same internet-based supplier in Texas. In Minnesota, the outbreak PFGE subtype of S. Typhimurium was isolated from the snakes, frozen feed rodents, and the classroom environment. Three human cases were identified in Michigan, Pennsylvania, and Wyoming. The outbreak PFGE subtype of S. Typhimurium was isolated from the Pennsylvania case's frozen rodents and the Michigan case's pet snake. The outbreak PFGE subtype of S. Typhimurium was also isolated from the supplier's rodent facility. This was a S. Typhimurium outbreak associated with frozen rodents. Human transmission likely occurred through direct contact with snakes and contaminated environmental surfaces. This report represents the second recent multi-state salmonellosis outbreak associated with commercially distributed rodents. Stronger oversight of the commercial rodent industry is warranted.     

A longitudinal assessment of periodontal health status in 53 Labrador retrievers

Objectives

To determine the incidence and rates of progression of gingivitis and periodontitis in Labrador retrievers.

Materials and Methods

Fifty‐three dogs, aged 1·1 to 5·9 years, had their periodontal health assessed every 6 months for up to 2 years. The extent of gingivitis and periodontitis was measured around the whole gingival margin of every tooth under general anaesthesia.

Results

All dogs had gingivitis at the initial assessment. The majority (64·2%) of tooth aspects had very mild gingivitis. The palatal/lingual aspect of all tooth types was most likely to show bleeding when probed: 63·0% of these aspects had mild or moderate gingivitis. Over 2 years, 56·6% of dogs developed periodontitis and dogs as young as 1·9 years were affected. There was a significant positive correlation between the proportion of teeth with periodontitis and age. In total, 124 teeth (5·7%) developed periodontitis; 88 (71·0%) of these were incisors. The palatal/lingual aspect of the incisors developed the disease first (2·8% of incisor aspects).

Clinical Significance

Periodontitis developed in regions that are difficult to see in conscious dogs implying that detection and treatment of disease requires periodic sedation or anaesthesia.     

Effects of Full-Stream Carbon Filtration on the Development of Head and Lateral Line Erosion Syndrome (HLLES) in Ocean Surgeon

Abstract

Head and lateral line erosion syndrome (HLLES) is a common but very poorly understood disease of marine aquarium fish. One suspected etiology is the use of granulated activated carbon (GAC) to filter the water. Seventy-two ocean surgeons Acanthurus bahianus were distributed among three carbon-negative control systems and three GAC-treated systems such that each tank contained approximately the same total body mass. Each replicate system was made up of two 250-L circular tanks with a common filtration system (6 fish per tank, 12 fish per replicate system). The GAC-treated tanks were exposed to full-stream, extruded coconut shell activated carbon, which produced a mean total organic carbon content of 0.4 mg/L. The results of this study indicate that extruded coconut shell activated carbon filtering at full-stream rates can cause HLLES-type lesions in ocean surgeons. The HLLES developed exponentially over 15 d, beginning in the chin region. This was followed by pitting in the cheek region, which expanded until erosions coalesced. Once the carbon was discontinued, the processes reversed in a mean time of 49 d. As the lesions healed, they reverted from the coalesced to the pitted stage and then darkened before returning to normal.

Received September 2, 2010; accepted March 20, 2011     

Carnein, a serine protease from noxious plant weed Ipomoea carnea (morning glory)

A new serine protease from the latex of Ipomoea carnea spp. fistulosa (Morning glory), belonging to the Convolvulaceae family, was purified to homogeneity by ammonium sulfate fractionation followed by cation exchange chromatography. The enzyme, named carnein, has a molecular mass of 80.24 kDa (matrix-assisted laser desorption/ionization time-of-flight) and an isoelectric point of pH 5.6. The pH and temperature optima for proteolytic activity were 6.5 and 65 degrees C, respectively. The extinction coefficient (epsilon2801%) of the enzyme was estimated as 37.12, and the protein molecule consists of 35 tryptophan, 76 tyrosine, and seven cysteine residues. The effect of several inhibitors such as iodoacetic acid, diisopropylfluorophosphate, phenyl-methanesulfonyl fluoride, chymostatin, soybean trypsin inhibitor, HgCl2, 3S-3-(N-{(S)-1-[N-(4-guanidinobutyl)carbamoyl]3-ethylbutyl}carbamoyl)oxirane-2-carboxylic acid, N-ethyl maleimide, ethylene glycol-bis(alpha-amino ethyl ether)tetraacetic acid, ethylenediamminetetraacetic acid, and o-phenonthroline indicates that carnein belongs to the family of serine proteases. The enzyme is not prone to autolysis even at very low concentrations. The N-terminal sequence of carnein (T-T-H-S-P-E-F-L-G-L-A-E-S-S-G-L-X-P-N-S) exhibited considerable similarity to those of other plant serine proteases; the highest similarity was with alnus AG12, one of the subtilase family endopepetidases.     

Phytochemical and nutrient composition of the freeze-dried amazonian palm berry, Euterpe oleraceae mart. (acai)

Euterpe oleraceae is a large palm tree indigenous to the Amazon River and its tributaries and estuaries in South America. Its fruit, known as acai, is of great economic value to native people. In this study, a standardized freeze-dried acai fruit pulp/skin powder was used for all analyses and tests. Among many findings, anthocyanins (ACNs), proanthocyanidins (PACs), and other flavonoids were found to be the major phytochemicals. Two ACNs, cyandin 3-glucoside and cyanidin 3-rutinoside were found to be predominant ACNs; three others were also found as minor ACNs. The total content of ACNs was measured as 3.1919 mg/g dry weight (DW). Polymers were found to be the major PACs. The concentration of total PACs was calculated as 12.89 mg/g DW. Other flavonoids, namely, homoorientin, orientin, isovitexin, scoparin, and taxifolin deoxyhexose, along with several unknown flavonoids, were also detected. Resveratrol was found but at a very low concentration. In addition, components including fatty acids, amino acids, sterols, minerals, and other nutrients were analyzed and quantified. Total polyunsaturated fatty acid, total monounsaturated fatty acid, and total saturated fatty acids contributed to 11.1%, 60.2%, and 28.7% of total fatty acid. Oleic acid (53.9%) and palmitic acid (26.7%) were found to be the two dominant fatty acids. Nineteen amino acids were found; the total amino acid content was determined to be 7.59% of total weight. The total sterols accounted for 0.048% by weight of powder. The three sterols B-sitosterol, campesterol, and sigmasterol were identified. A complete nutrient analysis is also presented. Microbiological analysis was also performed.     

Is it possible to store spotted wolffish (Anarhichas minor) sperm by refrigeration?

Fish Physiology and Biochemistry - Spotted wolffish Anarhichas minor reproduction in captivity is dependent on in vitro fertilization. However, it is often challenging to acquire sufficient fresh...     

Pharmacokinetics of gatifloxacin in broiler chickens following intravenous and oral administration

1. The pharmacokinetics of gatifloxacin were investigated following intravenous and oral administration of a single dose at a rate of 10?mg/kg body weight in broiler chicks.

2. Drug concentration in plasma was determined using High Performance Liquid Chromatography with ultraviolet detection on samples collected at frequent intervals after drug administration.

3. Following intravenous administration, the drug was rapidly distributed (t_1/2α: 0·33?±?0·008?h) and eliminated (t_1/2β: 3·62?±?0·03?h; Cl_B: 0·48?±?0·002?l/h/kg) from the body.

4. After oral administration, the drug was rapidly absorbed (C _max: 1·74?±?0·024?µg/mL; T _max: 2?h) and slowly eliminated (t_1/2β: 3·81?±?0·07?h) from the body. The apparent volume of distribution (V_d(area)), total body clearance (Cl_B) and mean residence time (MRT) were 3·61?±?0·04?l/kg, 0·66?±?0·01?l/h/kg and 7·16?±?0·08?h, respectively. The oral bioavailability of gatifloxacin was 72·96?±?1·10 %.

5. Oral administration of gatifloxacin at 10?mg/kg is likely to be highly efficacious against susceptible bacteria in broiler chickens.