Exposure of workers to airborne microorganisms in open-air swine houses

This study quantified the levels of airborne microorganisms in six swine farms with more than 10,000 pigs in subtropical Taiwan. We evaluated breeding, growing, and finishing stalls, which were primarily open-air buildings, as well as partially enclosed farrowing and nursery piggeries. Airborne culturable bacteria, gram-negative bacteria, and fungi were placed on appropriate media by using an all-glass impinger or single-stage Andersen microbial sampler. Results showed that mean concentrations of culturable bacteria and gram-negative bacteria were 3.3 x 10(5) and 143.7 CFU/m(3), respectively. The concentration of airborne culturable fungi was about 10(3) CFU/m(3), with Cladosporium the predominant genus. The highest airborne levels of culturable bacteria and gram-negative bacteria were identified in the finishing units. The air of the nursery stalls was the least contaminated with culturable and gram-negative bacteria. Irregular and infrequent cleaning, high pig density, no separation of wastes from pen floors, and accumulation of water as a result of the processes for cleaning and reducing pig temperature possibly compromise the benefits of the open characteristic of the finishing units with respect to airborne bacterial concentration.     

An assessment of methods for measuring volumes of planktonic bacteria, with particular reference to television image analysis

Several methods for measuring volumes of planktonic bacteria were compared. The eyepiece micrometer grossly overestimated cell width (47–65%) and hence volume (73%). Shrinkage occurred with scanning electron microscopy, so volumes were underestimated by about 77%. All the other methods gave similar results (mean volume = 0.133 µm³). The optimum technique was to filter acridine orange stained bacteria through polycarbonate membrane filters (0.2 µm) which were photographed with epifluorescence microscopy using Kodak Tri-X pan film. We recommend that volumes are estimated from individual area and perimeter measurements of at least 200 bacteria with a Quantimet 800 or Q10 image analyzer.     

A survey of soil microorganisms,with particular reference to the actinomycetes as sources of substances toxic to Heliothis virescens

Cultures of microorganisms isolated from cultivated soils were grown in submerged fermentation in test tubes kept on a rotary shaker at 28°C for 5 days using a fermentation medium composed primarily of soybean flour and dextrose. The beers were harvested and centrifuged, and the supernatants were incorporated at a dilution of 1:10 into artificial diets on which neonate larvae of Heliothis virescens were allowed to feed ad libitum for 7 days. If the beer killed or markedly retarded the development of at least 50% of the test larvae, the culture was regrown in shaken cultures in 500-ml Erlenmeyer flasks and assayed again. If a culture produced toxic beers in both fermentations, it was considered active. Over 2100 soil isolates were tested, of which an estimated 95% were actinomycetes. Slightly over 0.4% of the isolates were active, all of which, probably due to our selection procedure, were actinomycetes.     

Inheritance of quantitative traits in crosses between two Pisum sativum subspecies with particular reference to their breeding value

The experimental study was conducted during the period of 2008-2010 at the experimental field of the Institute of Forage Crops in Pleven. The hybridization scheme included direct and back crosses covering four varieties of forage pea (Pisum sativum L.), namely two spring ones, Usatii 90 and Kamerton from Ukraine, and a winter one from Bulgaria, Pleven 10. There was analyzed the inheritance of quantitative traits such as plant height, height to first pod, pod number per plant, seed number per plant, seed number per pod, seed weight per plant and number of fertile nodes per plant of parental components (P1 and P2) and both first (F1) and second (F2) hybrid generations. The cross Usatii 90 x Pleven 10 showed the highest real heterosis effect for plant height (8.26%), pods per plant (158.79%), seeds per plant (272.16%), seeds per pod (42.09%), seed weight per plant (432.43%) and number of fertile nodes per plant (117.14%). The cross Pleven 10 x Usatii 90 had the highest real heterosis effect height to first pod (11.06%). In F2 plants, the strongest depression for plant height (5.88%), seeds per plant (57.88%), seeds per pod (55.93%) and seed weight per plant (55.99%) was in the cross Usatii 90 x Pleven 10, for height to first pod (1.47%) in the cross Kamerton x Pleven 10 and for number of fertile nodes per plant (15.91%) in the cross Pleven 10 x Usatii 90. The highest positive degree of transgression for number of fertile nodes per plant (165.64%) and seed weight per plant (162.10%) was in the cross Pleven 10 x Kamerton and for pod number per plant (102.54%) and seeds per plant (99.13%) in Kamerton x Pleven 10. The stability of the characters was determined. Low variability in F1 and F2 was found in plant height (3.97-6.85%). Variability of number seeds per plant in F1 was highest (11.86-33.23%). For all other traits, the variability varied from average to high. A lower narrow-sense heritability coefficient was observed for plant height, height to first pod, pods per plant, seeds per plant and seed weight per plant (from 0.001 to 0.230). In few cases, such as in fertile nodes per plant (0.39 and 0.81) and seeds per pod (0.44), the coefficients ofbroad-sense heritability were higher.     

The role of growth hormone in the regulation of protein metabolism with particular reference to conditions of fasting

Growth hormone (GH) has potent protein anabolic actions, as evidenced by a significant decrease in lean body mass and muscle mass in chronic GH deficiency, and vice versa in patients with acromegaly. Depending on the prevailing physiological conditions and on which tissues and which proteins are under examination, the mechanisms involved include both stimulation of protein synthesis and restriction of protein breakdown. Apart from the possible direct effects of GH on protein dynamics, a number of additional anabolic agents, such as insulin, insulin-like growth factor-I and free fatty acids (FFA), are activated. Some of the most recent studies in the field have demonstrated a decisive role of stimulation of lipolysis and high circulating levels of FFA in orchestrating the maintenance of the protein pool of the body.     

An ecological study of a small New Zealand stream with particular reference to the Oligochaeta

The composition, temporal and spatial distribution, and productivity of profundal benthos were investigated in a Colorado Front Range reservoir which impounds water diverted from the Western Slope of the Rocky Mountains. Horsetooth Reservoir, 10.6 km × 1.0 km, consists of three basins with depths greater than 50 m connected by two equalizing channels ca. 30 m deep. Water quality parameters did not vary significantly between sites, but temperature, pH, and dissolved oxygen varied seasonally. The composition and organic content of sediment exhibited a gradient from inlet to outlet which significantly influenced faunal density and distribution patterns. Although 28 genera of macroinvertebrates were collected, the oligochaetes Tubifex tubifex (Müller) and Limnodrilus hoffmeisteri Claparède comprised 97.6% of the total organisms. Chironomids comprised 2.2%. The relative contribution of chironomids to total biomass decreased with increasing depth; the reverse was true for oligochaetes. Mean annual density ranged from 3,827 to 51,901 total organisms/m² for six sampling sites. Mean annual biomass varied from 0.16 to 2.3 g ash-free dry wt/m². Annual turnover ratios ranged from 3.6 to 4.5. Annual production estimates varied from 7.2 to 82.8 kg/ha ash-free dry weight, averaging 39.3 kg/ha or 26.9 kcal/m².     

Observations on the use of membrane filtration and liquid impingement to collect airborne microorganisms in various atmospheric environments

The influence of sample-collection-time on the recovery of culturable airborne microorganisms using a low-flow-rate membrane-filtration unit and a high-flow-rate liquid impinger were investigated. Differences in recoveries were investigated in four different atmospheric environments, one mid-oceanic at an altitude of ~10.0 m, one on a mountain top at an altitude of ~3,000.0 m, one at ~1.0 m altitude in Tallahassee, Florida, and one at ~1.0 m above ground in a subterranean-cave. Regarding use of membrane filtration, a common trend was observed: the shorter the collection period, the higher the recovery of culturable bacteria and fungi. These data also demonstrated that lower culturable counts were common in the more remote mid-oceanic and mountain-top atmospheric environments with bacteria, fungi, and total numbers averaging (by sample time or method categories) <3.0 colony-forming units (CFU) m⁻³. At the Florida and subterranean sites, the lowest average count noted was 3.5 bacteria CFU m⁻³, and the highest averaged 140.4 total CFU m⁻³. When atmospheric temperature allowed use, the high-volume liquid impinger utilized in this study resulted in much higher recoveries, as much as 10× greater in a number of the categories (bacterial, fungal, and total CFU). Together, these data illustrated that (1) the high-volume liquid impinger is clearly superior to membrane filtration for aeromicrobiology studies if start-up costs are not an issue and temperature permits use; (2) although membrane filtration is more cost friendly and has a ‘typically’ wider operational range, its limits include loss of cell viability with increased sample time and issues with effectively extracting nucleic acids for community-based analyses; (3) the ability to recover culturable microorganisms is limited in ‘extreme’ atmospheric environments and thus the use of a ‘limited’ methodology in these environments must be taken into account; and (4) the atmosphere culls, i.e., everything is not everywhere.     

An HRP study in the cat of brainstem projections to the spinal cord, with particular reference to sacral afferents

Cells of origin of the spinal projections from the brainstem of the cat have been studied by means of retrograde axonal transport of horseradish peroxidase (HRP). Following injections of HRP into various levels of the spinal cord, many labeled cells were found in several structures in the brainstem. The labeled cells occurred in the raphe nuclei, reticular formation, vestibular complex, and nuclei of the dorsolateral pontine tegmentum. In the dorsolateral pontine tegmentum, many labeled cells were found in the nuclei of locus coeruleus, subcoeruleus and K?lliker-Fuse. In the coeruleus and subcoeruleus, the greatest number of labeled cells were found, when HRP was injected into the sacral cord. No difference emerged, however, in the number of labeled cells appearing in the K?lliker-Fuse nucleus after injection of the enzyme into different levels of the spinal cord. It appears that neurons in the lateral vestibular nucleus which project to different levels of the spinal cord are located in different parts of this nucleus.     

Systematic review of exposure to albendazole or mebendazole during pregnancy and effects on maternal and child outcomes,with particular reference to exposure in the first trimester

Soil-transmitted helminth infections cause an important burden of morbidity worldwide, primarily from blood loss and malabsorption of nutrients. Where STH endemicity ≥20%, the World Health Organization (WHO) recommends preventive chemotherapy with single dose anthelminthic drugs: albendazole or mebendazole. Although WHO recommends that women of reproductive age, including pregnant women after the first trimester, be included in large-scale deworming programs, there are concerns related to the use of anthelminthic drugs during pregnancy, especially inadvertent use in the first few weeks when the pregnancy may not yet be confirmed. We therefore conducted a systematic review using the MEDLINE database with the aim of appraising all peer-reviewed evidence, published up to July 1, 2018, on the association between exposure to albendazole or mebendazole and outcomes in pregnant women, including those in the first trimester of pregnancy, and their children. From a yield of 205 papers based on titles alone, 58 papers, reporting results from 46 originator studies conducted in pregnant populations, constituted the initial evidence base. Among the nine originator observational studies which had included women in the first trimester of pregnancy within their study population, five compared birth outcomes between women exposed in the first trimester with women who were not exposed, and none reported higher rates of adverse birth outcomes in the exposed group. Due to heterogeneity in terms of study design, sample size, deworming drug, dosage and outcomes measured, data from these studies could not be pooled. Based on this cumulative evidence, it is unlikely that inadvertent exposure to albendazole or mebendazole in the first trimester carries an additional risk of adverse birth outcomes. To optimize relevance for policy making, future research in pregnant populations should aim to provide data disaggregated by trimester and to report on maternal and child adverse events, whenever possible.     

An HRP study in the monkey of olivary projections from the mesodiencephalic structures with particular reference to pretecto-olivary neurons

The cells of origin of the olivary projection from mesodiencephalic structures have been demonstrated in the Japanese monkey (Macaca fuscata) with the horseradish peroxidase (HRP) method. Particular attention has been paid to the pretecto-olivary projection which is entirely ipsilateral and originates from the nucleus of the optic tract (NOT), the posterior (or principal) pretectal nucleus (PPN), the sublentiform nucleus (SL), and the (pretectal) ventral lateral zone (VLZ). Pretecto-olivary cells are small-medium sizes of oval or fusiform types. To facilitate comparison among the findings of several experiments, a diagram of the macaque olive, as visualized unfolded, was constructed (Fig. 1). Although a topographic correlation has not emerged clearly from the present experiments, the pattern of the pretecto-olivary projection in the monkey appears to be similar to that found in the cat. Participation of some of the pretectal nuclei in the optokinetic nystagmus and the vestibulo-ocular reflex is discussed in connection with the pretecto-olivary and olivocerebellar projections.     

Immunogold localization of photosynthetic enzymes in leaves of various C4 plants, with particular reference to pyruvate orthophosphate dikinase

Cellular localization of photosynthetic enzymes was investigated by immunogold electron microscopy for leaves of nine C4 grasses (three NADP-malic enzyme (NADP-ME)subtype species, three NAD-malic enzyme (NAD-ME) subtype species, and three phosphoenolpyruvate carboxykinase (PCK) subtype species), two C4 sedges (NADP-ME subtype species) and two C4 dicots (an NADP-ME and an NADP/NAD-ME subtype species). In leaves of all species, immunogold labelling was present for phosphoenolpyruvate carboxylase in the cytosol of the mesophyll cells (MC) and for ribulose-1,5-bisphosphate carboxylase/oxygenase in the chloroplasts of the bundle sheath cells (BSC). However, considerable specific variation was found in the intercellular patterns of labelling for pyruvate orthophosphate dikinase (PPDK). In the NADP-ME grasses, two NAD-ME grasses, and the dicots, significant labelling for PPDK was present in the both the BSC and the MC chloroplasts. In the other NAD-ME grass, the PCK grasses, and the sedges, labelling for PPDK was present almost exclusively in the chloroplasts of the MC. These patterns were observed in the leaves of both young seedlings and mature plants. These results indicate that the accumulation of PPDK in leaves of C4 plants is not necessarily restricted to the MC, although the chloroplasts of the MC accumulate more than those of the BSC.Key words: C4 plants, immunolocalization, phosphoenolpyruvate carboxylase, pyruvate orthophosphate dikinase, ribulose-1,5-bisphosphate carboxylase/oxygenase.