Health Risk Assessment of Petrol Station Workers in the Inner City of Bangkok,Thailand, to the Exposure to BTEX and Carbonyl Compounds by Inhalation

The occupational health risk of petrol station workers from exposure to BTEX and carbonyl compounds via inhalation was estimated in the inner city of Bangkok. Personal sampling was performed within the workers’ breathing zone using 2,4 dinitrophenylhydrazine cartridges and charcoal glass tubes connected to a personal air pump during eight working hours at six petrol stations. BTEX and carbonyl compounds were quantitatively analyzed by GC/FID and HPLC/UV, respectively. Of all detectable BTEX and carbonyl compounds, the levels of the four most prevalent compounds (benzene, ethylbenzene, formaldehyde, and acetaldehyde) were used to assess the lifetime cancer risk and 95% confidence interval of the risk levels were found to be totally higher than acceptable criteria for benzene (1.82 × 10^–4–2.50 × 10^–4), formaldehyde (7.81 × 10^–6–1.04 × 10^–5), ethylbenzene (4.11 × 10^–6–5.52 × 10^–6), and acetaldehyde (1.39 × 10^–6–2.45 × 10^–6). Thus, petrol station workers in the inner city of Bangkok have a potentially high cancer risk through inhalation exposure. With respect to the noncarcinogenic agents, toluene, m,p-xylene, o-xylene, and propionaldehyde, all non-cancer health risk were within hazard quotients of 1 and of acceptable risk.     

Stage-specific induction of systemic acquired resistance by fruit extracts of Azadirachta indica

In the present study, the efficacy of aqueous fruit extract of Azadirachta indica A. Juss. (Neem) on induction of systemic acquired resistance (SAR) in tomato against Pseudomonas syringae pv. tomato through enhancement in the activity of polyphenol oxidase (PPO) at different ages was studied. Plants at 6, 8, 10 and 12?weeks of age were selected. A single leaf at the third node from the base of each plant was treated either singly or with different combinations of the pathogen and Neem fruit extract. Samples were collected from the non-treated leaves at an interval of 24?h up to five?days for enzyme assay and after two?weeks for disease development from both treated and untreated plants. The results demonstrate that the neem fruit extract could induce additional PPO isoforms both locally as well as systemically. The PPO activity was observed to be elevated in both the treated and non-treated leaves leading to induction of SAR. The induction of SAR enhances with the increase in the age of the plant.     

A Simple Synthesis of α-Acaridial

Many microorganisms isolated from fish viscera formed trans fatty acids. One of them was identified as Cladosporium sphaerospermum. This is the first report of a fungus forming trans fatty acids. Several bacteria, identified as Pseudomonas sp., Pseudomonas putida, Marinomonas sp., and Schewanelia putrefaciens, also formed frans-octadecenoic acids, which increased on growth at high temperature or with phenol. The trans-octadecenoic acids comprised a mixture of various double bond-positional isomers, such as Δ8, Δ9, Δ10, Δ11, and Δ12.     

Interaction of Ddc1 and RPA with single-stranded/double-stranded DNA junctions in yeast whole cell extracts: Proteolytic degradation of the large subunit of replication protein A in ddc1Δ strains

To characterize proteins that interact with single-stranded/double-stranded (ss/ds) DNA junctions in whole cell free extracts of Saccharomyces cerevisiae, we used [³²P]-labeled photoreactive partial DNA duplexes containing a 3′-ss/ds-junction (3′-junction) or a 5′-ss/ds-junction (5′-junction). Identification of labeled proteins was achieved by MALDI-TOF mass spectrometry peptide mass fingerprinting and genetic analysis. In wild-type extract, one of the components of the Ddc1-Rad17-Mec3 complex, Ddc1, was found to be preferentially photocrosslinked at a 3′-junction. On the other hand, RPAp70, the large subunit of the replication protein A (RPA), was the predominant crosslinking product at a 5′-junction. Interestingly, ddc1Δ extracts did not display photocrosslinking of RPAp70 at a 5′-junction. The results show that RPAp70 crosslinked to DNA with a 5′-junction is subject to limited proteolysis in ddc1Δ extracts, whereas it is stable in WT, rad17Δ, mec3Δ and mec1Δ extracts. The degradation of the RPAp70-DNA adduct in ddc1Δ extract is strongly reduced in the presence of the proteasome inhibitor MG 132. We also addressed the question of the stability of free RPA, using anti-RPA antibodies. The results show that RPAp70 is also subject to proteolysis without photocrosslinking to DNA upon incubation in ddc1Δ extract. The data point to a novel property of Ddc1, modulating the turnover of DNA binding proteins such as RPAp70 by the proteasome.     

Morphological and Morphometrical Characterization of Meloidogyne incognita from Different Host Plants in Four Districts of Punjab,India

The population of M. incognita, the root knot nematode (RKN) was found infesting five different host plants (okra, banana, sunflower, bottle gourd, and brinjal) out of 24 examined from four districts of Punjab, India (Gurdaspur, Ludhiana, Patiala, and Hoshiarpur). Morphological and morphometrical characterization indicated that in the case of mature female, the characters of body length and width, neck length, ratio ‘a’, anus to tail terminus (ATT), interphasmid distance (IPD), and perineal pattern were recorded as stable characters. These taxonomic characters can be reliable for identification. All characters of second-stage juvenile (J2) such as body length, stylet length, head to median bulb length (H-MB), distance from median bulb to excretory pore (MB-EP), tail length, anal body width (ABW), and ratios C and C’ were highly variable. Analysis of interpopulation morphometric characters of mature female of M. incognita, namely, body length, width, and ratio ‘a’ were moderately variable characters (CV 0.26% to 20%) and stylet length, neck length, length of median bulb (LMB), and width of median bulb (WMB) were highly variable (CV 1.0% to 36.1%). In the perineal pattern, the two characters ATT and IPD were moderately variable (CV 8.8% to 17.6%) and two characters, anus to vulval slit (AVS) and length of vulval slit (LVS), were highly variable (CV 2.1% to 40.5%). In J2, body length, stylet length, H-MB, MB-EP, ABW, tail length, ratios C, and C’ were highly variable characters (CV > 12%).     

Diversity and convergence in the mechanisms establishing L/R asymmetry in metazoa

Differentiating left and right hand sides during embryogenesis represents a major event in body patterning. Left–Right (L/R) asymmetry in bilateria is essential for handed positioning, morphogenesis and ultimately the function of organs (including the brain), with defective L/R asymmetry leading to severe pathologies in human. How and when symmetry is initially broken during embryogenesis remains debated and is a major focus in the field. Work done over the past 20 years, in both vertebrate and invertebrate models, has revealed a number of distinct pathways and mechanisms important for establishing L/R asymmetry and for spreading it to tissues and organs. In this review, we summarize our current knowledge and discuss the diversity of L/R patterning from cells to organs during evolution.     

Effects of Dissolved Oxygen Tension on Microbial Ethylene Production in Continuous Culture

Pseudomonas sp. strain ST-200 isolated from a humus soil effectively oxidizes cholesterol dissolved in organic solvents but not that suspended in the growth medium. The organism does not assimilate cholesterol. This organism oxidized a variety of 5α- or 5-ene-sterols dissolved in organic solvent. First, the 3β-OH group was oxidized to a ketone group. The 3α-OH group was scarcely oxidized. Successively, C-6 position of 5-ene-steroids was hydroxylated, and a double bond of 5-ene-steroids was transferred from Δ⁵ to Δ ⁴. Then, the 6-OH group was oxidized to a ketone group. Persolvent fermentation with ST-200 would provide an effective, convenient, and stereospecific method to oxidize the C-3 and C-6 positions of steroids.     

A Rapid Method for Purification of d-Glucoside 3-Dehydrogenase

The stability of palm oil was tested by subjecting it to elevated temperatures for different durations of time, viz; at 80°C for 150 hr and 60°C for 400 hr.

The following results were obtained.

(1) The absorption spectrum resembled that of carotenoid and this changed progressively with a rise in peroxide and carbonyl values during the first 80 hr at 80°C.

(2) Peroxide values of Sabah palm oil were higher compared to Sumatra oil, there were marked increases in peroxide and carbonyl values of alkali refined oil as compared to crude oil. On the contrary, the residual color of crude Sumatra oil decreased considerably. Moreover, the steam emulsion number of alkali refined Sumatra oil was double the initial value after 400 hr.