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PubMed2006

Cotton (Gossypium hirsutum L.).

Considering the economic importance of cotton in many developing and developed countries, there is an urgent need to accelerate the application of biotechnological tools to address the problems associated with the production of this crop and to improve the quality of fiber and seed. This requires a simple yet robust gene delivery/transformant recovery system. A protocol for the production of transgenic cotton plants was refined in our laboratory. It involves Agrobacterium-mediated transformation of cotton cells, selection of stable transgenic callus lines, and recovery of plants via somatic embryogenesis. A detailed description of the protocol is provided in this chapter.

Agrobacterium tumefaciens↗
PubMed1987

Effect of compensatory growth on regulation of growth and lactation: response of dairy heifers to a stair-step growth pattern.

The primary objective of this study was to improve the productive efficiency of growth via optimal use of both high fiber-low quality and high energy-high protein feeds in diets for growing dairy cattle. Twenty Holstein heifers were randomly assigned to either a control or treatment group. The control diet met the National Research Council (NRC) requirement for .45 kg/d gain, with heifers calving at 24 to 26 mo of age. The test groups were fed according to a 5-2-5-2 mo schedule in which the nutrient density was alternately 15% below or 40% above the NRC requirement. Results showed that the heifers on the test dietary regimen (compensatory growth) gained more and consumed less, resulting in significantly improved efficiency of growth (body gain/dry matter intake X 100), energy (body gain X 1,000/metabolizable energy (ME) intake) and protein utilization (body gain/protein intake X 100) in comparison to control animals (13.0 vs 7.3%; 57.9 vs 32.6 g/Mcal ME; 96.5 vs 54.2%, respectively). Marked changes in average concentration of urea-N, glucose, triglycerides, cholesterol and lecithin cholesterol acyltransferase activity in blood were seen for test heifers during the stair-step growth phase (i.e., alternating maintenance and compensatory). Evidence from this experiment suggests that the phased growth (stair-step) system offers a simple, practical and cost-effective method for raising dairy heifers.

Animal Feed↗
PubMed2026

Genome-Wide Characterization of the ZIP Transporter Family in Sea Island Cotton (Gossypium barbadense L.) and Expression Profiling Under Heavy Metal and Pathogen Stresses.

G. barbadense represents an indispensable germplasm resource for high-quality textile fiber and disease resistance; nevertheless, systematic information regarding its ZRT/IRT-like protein (ZIP) gene family remains limited. Here, a total of 46 GbZIP genes were identified across the G. barbadense genome. Comprehensive bioinformatic investigations revealed uneven chromosomal distribution and confirmed that segmental/whole-genome duplications, supplemented by localized tandem duplications, drove family expansion. Members clustered within the same phylogenetic clades shared conserved motif organization and gene architecture, while promoter regions harbored abundant cis-acting elements associated with phytohormone and stress signaling. Transcriptome profiling indicated distinct expression patterns across vegetative/reproductive tissues, fiber and ovule developmental stages, and diverse abiotic stress conditions (cold, hot, drought, and salt). Quantitative Real-Time PCR (qRT-PCR) further validated that several GbZIP candidates exhibited temporal expression variations upon exposure to cadmium toxicity, V. dahliae infection, and combined Cd-V. dahliae stress. Specifically, GbZIP13, GbZIP18, GbZIP27, and GbZIP36 displayed prominent broad-spectrum responses to all three stress conditions, whereas GbZIP16, GbZIP29, and GbZIP30 showed stress-specific regulatory divergence. Overall, this study aims to systematically analyze the evolutionary characteristics and expression patterns of the GbZIP family, and to specifically evaluate the response differences under Cd stress, V. dahliae stress, and combined stress, in order to identify potential key candidate genes.

Gossypium barbadense↗
PubMed2001

Performance of asbestos fibre counting laboratories by transmission electron microscopy.

In France, the owners of buildings have been obliged since February 1996 to ascertain whether asbestos has been incorporated into surfacing materials, insulation products or false ceilings. In certain circumstances, there is also a requirement to measure the airborne asbestos fibre concentration. Three years (1996-1998) of asbestos fibre count reporting are evaluated for the proficiency testing scheme organized in France to evaluate the performance of laboratories using an indirect-transfer transmission electron microscopy procedure to measure the airborne asbestos fibre concentration. Each year eight filters are distributed to each participating laboratory. These filters are obtained by filtering a suspension containing chrysotile or amphibole fibres. In 1996, 36% of the laboratories were rated 1 (the best performers; i.e. those providing counts close to the reference value). Performance improved appreciably in the last round where 85% of the laboratories were rated 1.

Air Pollution, Indoor↗
PubMed1991

Lithotripsy of gallstones by means of a quality-switched giant-pulse neodymium:yttrium-aluminum-garnet laser. Basic in vitro studies using a highly flexible fiber system.

The quality-switched neodymium:yttrium-aluminum-garnet laser represents a new instrument for athermal fragmentation of gallstones by transformation of optical energy into mechanical energy in the form of shock waves via local plasma formation. A highly flexible 300-micron fiber transmission system was used in basic investigations to determine the influence of varying pulse repetition rates (5-30 Hz) and pulse energies (15 and 20 mJ) on shock wave intensity and stone fragmentation in vitro for 105 biliary calculi of known size and chemical composition. After performance of 1200 shock wave pressure measurements using polyvinylidenefluoride hydrophones, stone fragmentation was analyzed by determination of fragment removal rates (volume of fragments removed per fragmentation time), ablation rates (mean volume removed per laser pulse), and median fragment sizes for each laser setting. With the quality-switched neodymium:yttrium-aluminum-garnet laser system, all concrements could be reliably disintegrated into small fragments (median diameter, 0.7-1.7 mm). Compared with pure cholesterol stones, a significantly higher fragment removal rate was achieved in cholesterol stones containing 30% calcium phosphate (P = 0.039), in cholesterol stones containing 20% pigment (P = 0.015), and in pure pigment stones (P = 0.007). Fragment removal rates, local shock wave pressures, and median grain sizes were significantly higher at a pulse energy of 20 mJ than with 15 mJ. Shock wave pressures showed a distinct dependence on pulse repetition rates at 20 mJ, yet not at 15 mJ. Because there is no evident hazard of thermal damage to tissue using the quality-switched neodymium:yttrium-aluminum-garnet laser, it appears to be a promising device for nonsurgical biliary stone therapy.

Aluminum↗
PubMed2004

Functional, electrophysiologic, and morphometric evaluation of nerve regeneration from coaptation on regenerated nerve fibers: experimental study in rabbits.

The importance of a sufficient number of nerve fibers at a proximal coaptation site is indisputable for the successful repair of nerves; however, the quality of nerve fibers required at this site has yet to be defined. The present study deals with the question of whether it is necessary to trim nerves back to unaffected neuronal tissue or whether the coaptation on recently regenerated nerve fibers, commonly believed to produce a poor quality of repair can, in fact, produce adequate nerve regeneration. Twenty New Zealand White rabbits received a standardized crush lesion on the peroneal nerves of both hind legs. Four weeks later, the nerves of the left hind legs (n = 20) were transected 10 mm distal to the previous crush lesion and coapted to the freshly regenerated nerve fibers. For comparison, on 10 right hind legs, the nerves were transected at the site of previous crushing (Group A, superimposition) or 10 mm proximal to the site of crushing on unscathed nerve fibers (Group B). Eleven weeks later, the quality of nerve regeneration was assessed by the toe-spreading reflex, electrophysiologic data, muscle weight, and histomorphologic evaluation. In the animals of Group A, the quality of nerve regeneration following coaptation on the regrown axons did not differ in any of the examined parameters from the quality of nerve fibers outgrown from the site of the superimposed lesion. Both lesions led to a completely functional reinnervation. Also in Group B, nerve action potential recording and histologic data on both sides did not reveal a significant difference between the number and maturation of nerve fibers equidistant from the suture site, shortly before muscle entrance. With this coaptation model, it could be demonstrated in the peroneal nerve of rabbits, that coaptation to recently regenerated nerve fibers leads to a significant functional regeneration.

Anastomosis, Surgical↗
PubMed1988

[Evaluation of the protein quality of silaged corn ear products with different crude fiber contents].

The assessment of the protein quality of silaged maize ear products was carried out on the basis of crude protein and amino acid analyses and of N balance measurings with growing pigs including comparative studies with maize corns and cereals. The differences found in the amino acid concentrations between the individual maize ear products could be verified on the basis of the analysed values of husks, cobs and corns. There were no significant differences in the parameters of total protein utilization (PNu, b-value) between the studied silages. The differing crude fibre content resulted, however, in reverse shifts in N excretion in faeces and urine, i.e. diminished protein digestibility was compensated by improved intermediary utilization.

Amino Acids↗
PubMed2006

Physiological function of insoluble dietary fiber prepared from exploded oak wood (Quercus mongolica).

This study investigated the production of insoluble dietary fiber using exploded and chemically treated oak wood (Quercus mongolica) and the physiological functions of prepared insoluble dietary fiber in laboratory animals. To produce high quality insoluble dietary fiber, the steam explosion treatment was performed at 25 kgf/cm2 pressure for 6 minutes. In the chemical analysis of insoluble dietary fiber, exploded oak wood was pretreated by 1% sodium hydroxide solution. The insoluble dietary fiber contained 7.6% residual lignin and 61.7% of alpha-cellulose. In order to compare the physiological functions of prepared insoluble dietary fiber with those of commercial insoluble dietary fiber, Sprague-Dawley male rats weighing 100 +/- 10 g were randomly assigned to one normal diet and five high cholesterol diets, containing 1% cholesterol. The high cholesterol diet groups were classified as the fiber-free diet (FF group), 5% commercial alpha-cellulose diet group (5C group), 10% commercial alpha-cellulose group (10C group), 5% insoluble dietary fiber group (5M group) and 10% insoluble dietary fiber group (10M group). Food intake, weight gain and food efficiency ratio in high cholesterol groups were significantly higher than those of the normal group, but there were no significant differences among the high cholesterol diet groups. In addition, there were no significant differences in the weights of liver, kidney and small intestine in insoluble dietary fiber-supplemented groups. Cecum weights in all insoluble dietary fiber groups were significantly higher than those of the FF group. There were no significant differences in the activities of the glutamic pyruvic transaminase (GPT) and glutamic oxaloacetic transaminase (GOT) among the insoluble dietary fiber-supplemented groups. In conclusion, the prepared insoluble dietary fiber and the commercially available insoluble fiber showed the same physiological effects. Moreover, the preparation method for the insoluble dietary fiber from the exploded oak wood was successful.

Alanine Transaminase↗
PubMed1998

Taste in chimpanzees. III: Labeled-line coding in sweet taste.

In peripheral taste the coding mechanism remains an enigma. Among coding theories the "across-fiber pattern" argues that activity across fibers codes for taste, whereas the "labeled line" claims that activity in a particular set of fibers underlies a taste quality. We showed previously that chimpanzee chorda tympani taste fibers grouped according to human taste qualities into an S-cluster, responding predominantly to sweet stimuli, a Q-cluster, sensitive to bitter tastants, and an N-cluster, stimulated by salts. The analysis showed that information in the S-line suffices to distinguish stimuli of one taste quality from the others. However, one condition for the labeled line remained: that blockage of activity in a particular line must cause blockage of one taste quality, but of no other, or its onset give rise to the sensation of a taste quality. Here we studied this requirement with gymnemic acids and miraculin. In humans and chimpanzees, gymnemic acids suppress the sweet taste of all sweeteners whereas miraculin adds a sweet taste quality to sour stimuli. Gymnemic acids also abolish miraculin-induced sweet taste. We found that gymnemic acids practically abolished the response to every sweetener in the chimpanzee S-cluster. Equally important, they had no effect on the responses of the Q- and N-clusters. After miraculin, the S-cluster fibers responded to acids as well as to sweeteners, although they had not responded to acids before miraculin. Gymnemic acids abolished this miraculin-induced response to acids and responses to sweeteners in the S-fibers. These results link the sweet taste quality to activity in fibers of the S-cluster. Thus the S-cluster fibers satisfy the definition of the labeled-line theory: "that activity in a particular fiber type represents a specific taste quality."

Animals↗
PubMed2001

Caffeoyl-coenzyme A 3-O-methyltransferase enzyme activity, protein and transcript accumulation in flax (Linum usitatissimum) stem during development.

Flax (Linum usitatissimum) is a commercially important fiber crop in Europe. Lignification of its phloem fibers, although weak, causes a decrease in their commercial quality. In flax, fiber lignin mainly consists of guaiacyl (G) units in contrast to the mixed guaiacyl-syringyl (G-S) lignin type occurring in xylem fibers. G lignins are reported as more condensed polymers due to a higher frequency of 5-5 linkages, whereas the deposition of syringyl end groups in lignins increases the proportion of alky-aryl ether linkages as beta-O-4-bonds. The type of linkages within a lignin polymer depends on the methylation of either the 3-hydroxyl groups or both 3-OH and 5-OH groups, which is controlled by two enzymes: caffeate 3-O-methyltransferase (COMT) and caffeoyl-coenzyme A 3-O-methyltransferase (CCoAOMT). First, we measured the in vitro activity of both OMTs in the flax stem tissues during stem development. CCoAOMT activity varied in the same way as COMT, i.e. increased gradually with stem maturity, from the top to the bottom of the stem, was maximum at the flowering stage and was lower, but still scorable, in the outer fiber-bearing tissues than in the xylem cells. In a second step, we focused our studies on the characterization of CCoAOMT in order to understand the implication of this enzyme in the lignification of flax fiber cells. CCoAOMT activity appeared to be associated with the accumulation of an acidic 33-kDa polypeptide identified as a CCoAOMT after immunological cross-reactivity with a poplar CCoAOMT and microsequencing. The differential accumulation of the CCoAOMT protein was confirmed by immunolocalization on tissue prints and correlated with that of the transcripts, suggesting a transcriptional regulation of CCoAOMT in the flax stem.

Journal Article↗
PubMed2004

Simple fiber-optic-based sensors for process monitoring: an application in wine quality control monitoring.

The goal of this research was to develop a simple and economical fiber-optic sensor technology for agrifood process monitoring. Toward this end, two fiber-optic sensors were developed to be used in combination: a single reflection V-bend sensor and a single fiber air-gap probe. The former is designed to be sensitive toward refractive index and the latter towards absorption. Experiments indicate that the micromachined V-bend fiber refractometer is most sensitive when the bend angle is centered around 140 degrees, at which angle the sensor may resolve changes in refractive index as small as 0.00015. Additionally, the V-bend sensor was found to be non-responsive toward sample absorption even in extremely absorbing solutions. The air-gap design absorption sensor, most commonly used for measurements in highly colored media, was found to be slightly sensitive towards refractive index. When the two sensors are used together, the response of the absorption sensor may be corrected for. This sensor combination is able to provide accurate measurements in situations where Beer's law is not obeyed. Results are presented that show that the sensor pair was successfully used to monitor wine sugar content (Brix), and color density and hue, parameters related to the age of the wine.

Absorption↗
PubMed2004

Free-range rearing of pigs during the winter: adaptations in muscle fiber characteristics and effects on adipose tissue composition and meat quality traits.

This research aimed to determine whether outdoor free-range rearing during the winter (average ambient temperature of 5 degrees C) vs. indoor housing (22 degrees C) affects meat quality, muscle metabolic traits, and muscle fiber characteristics. Forty Large White gilts and barrows were blocked by weight within each gender (20 per gender) and allotted randomly into two groups of pigs, with one reared indoors (IN) in individual pens (2.6 m2) and the other reared outdoors (OUT) from December to March in a 0.92-ha pasture. Both groups had free access to the same grower-finisher diet from 23 to 105 kg. At slaughter, adipose (backfat [BF] and omental fat [OF]) and muscle tissues (longissimus muscle [LM], rectus femoris [RF], and semitendinosus [ST]) were obtained from the right side of each carcass. Muscle fibers were stained and classified on the basis of stain reaction as slow-oxidative (SO), fast oxidative-glycolytic (FOG), and fast glycolytic (FG); fiber area and distribution were determined. Also assessed were carcass characteristics, initial and ultimate pH, L*a*b* values, drip loss percent, glycolytic potential (GP), and intramuscular lipid content, as well as the fatty acid profile of each muscle and adipose tissue. The OUT pigs had lower (P < 0.05) ADG and leaner (P < 0.05) carcasses than IN pigs. Rearing environment did not (P > 0.63) affect the intramuscular lipid content of the ST, but intramuscular lipid content was lower (P < 0.01) in the LM and tended to be higher (P = 0.06) in the RF of OUT than in those of IN pigs. In the BF outer layer of the OUT pigs, the higher PUFA content was compensated by both a lower (P < 0.01) saturated and monounsaturated fatty acid (MUFA) content, whereas in the OF, LM, and dark portion of the ST, only the percentage of MUFA was decreased (P < 0.01). In all tissues of the OUT pigs, the linolenic acid content was higher (P < 0.01) and the n-6:n-3 ratio was lower (P < 0.01). The GP of all muscles was higher (P < 0.01), and the ultimate pH of the RF and ST was lower (P < 0.01), in OUT compared with IN pigs. Lightness (L*) values were lower (P < 0.01) in the LM. Percentages of drip loss were higher (P < 0.05) in the LM and light portion of the ST of OUT than in those of IN pigs. The LM and RF of OUT pigs had more (P < 0.01) FOG and fewer (P < 0.01) FG fibers than muscles of IN pigs. Results suggest that rearing pigs outdoors increases aerobic capacity of glycolytic muscles but has little concomitant influence on meat quality traits.

Adaptation, Physiological↗
PubMed2006

An efficient protein preparation for proteomic analysis of developing cotton fibers by 2-DE.

Preparation of high-quality proteins from cotton fiber tissues is difficult due to high endogenous levels of polysaccharides, polyphenols, and other interfering compounds. To establish a routine procedure for the application of proteomic analysis to cotton fiber tissues, a new protocol for protein extraction was developed by optimizing a phenol extraction method combined with methanol/ammonium acetate precipitation. The protein extraction for 2-DE was remarkably improved by the combination of chemically and physically modified processes including polyvinylpolypyrrolidone (PVPP) addition, acetone cleaning, and SDS replacement. The protocol gave a higher protein yield and vastly greater resolution and spot intensity. The efficiency of this protocol and its feasibility in fiber proteomic study were demonstrated by comparison of the cotton fiber proteomes at two growth stages. Furthermore, ten protein spots changed significantly were identified by MS/tandem MS and their potential relationships to fiber development were discussed. To the best of our knowledge, this is the first time that a protocol for protein extraction from cotton fiber tissues appears to give satisfactory and reproductive 2-D protein profiles. The protocol is expected to accelerate the process of the proteomic study of cotton fibers and also to be applicable to other recalcitrant plant tissues.

Databases, Protein↗
PubMed1990

[Nutritional quality of the protein of the false lentil (Vicia sativa ssp. abovata (Ser) Gaudin].

The common vetch (Vicia sativa) is a legume that grows spontaneously in the central zone of Chile. It is consumed by the rural population, as lentil, and frequently it is utilized in animal feeding. The objective of the present work was to study the biological quality of its protein and protein digestibility, as well as its dietary fiber pattern. The samples studied were provided by the Instituto de Investigaciones Agropecuarias (INIA), where in its chemical composition, dietary fiber, biological protein quality (PER) and apparent and true protein digestibility, were determined. Results showed a high protein concentration (23.5%), higher than (in the legumes commonly consumed. Total dietary fiber and its fractions, insoluble and soluble fiber, attained values of 14.2%, 13.2% and 1.0% respectively. The PER in the raw material was 1.30 +/- 0.44 and 1.32 +/- 0.37 in the cooked one; supplementation with 0.15% DL-methionine caused a rise to 2.43 +/- 0.32, the casein value being 3.02 +/- 0.36. True digestibility was 76.2 +/- 2.0 in the raw material, and 73.8 +/- 2.2 in the cooked one. These findings suggest that common vetch has no termolabile toxics, which are normally present in legumes. However, the literature mentions that it contains a neurotoxic, the B-ciano-L-alanine. The present study suggests that common vetch is a promisory food resource; thus, it is highly desirable that studies be undertaken oriented to determine the toxicity in this food.

Animals↗
PubMed1993

[Microscopic quality control--numeric representation of asbestos fiber concentration in environmental air of the workplace].

The study aimed at assessing the reliability of determinations of respirable asbestos fibre concentration which were performed by selected laboratories of the Work Hygiene Departments of the Regional Sanitary Epidemiological Stations (RSES). Two rounds of microscopic specimen exchanges were organized, the specimens containing from 20 to 700 asbestos fibres per 1 mm2. The results of specimen density determinations performed by RSES analysts were compared with reference determinations (i.e. average density determinations performed by 7 workers of the Institute of Occupational Medicine, Lodz, checked by two international tests). During the first exchange, the RSES determinations were found to be significantly lower than the reference determinations. At the second exchange, they exceeded the reference values. The poor precision of determining asbestos fibre concentration by the majority of the RSES analysts makes it necessary to provide additional training for that group, apart from that a survey of the quality of RSES laboratory equipment should be carried out and a system of internal quality control for the RSES laboratories should be developed and implemented.

Air Pollutants, Occupational↗
PubMed2006

Recording high quality speech during tagged cine-MRI studies using a fiber optic microphone.

PURPOSE: To investigate the feasibility of obtaining high quality speech recordings during cine imaging of tongue movement using a fiber optic microphone. MATERIALS AND METHODS: A Complementary Spatial Modulation of Magnetization (C-SPAMM) tagged cine sequence triggered by an electrocardiogram (ECG) simulator was used to image a volunteer while speaking the syllable pairs /a/-/u/, /i/-/u/, and the words "golly" and "Tamil" in sync with the imaging sequence. A noise-canceling, optical microphone was fastened approximately 1-2 inches above the mouth of the volunteer. The microphone was attached via optical fiber to a laptop computer, where the speech was sampled at 44.1 kHz. A reference recording of gradient activity with no speech was subtracted from target recordings. RESULTS: Good quality speech was discernible above the background gradient sound using the fiber optic microphone without reference subtraction. The audio waveform of gradient activity was extremely stable and reproducible. Subtraction of the reference gradient recording further reduced gradient noise by roughly 21 dB, resulting in exceptionally high quality speech waveforms. CONCLUSION: It is possible to obtain high quality speech recordings using an optical microphone even during exceptionally loud cine imaging sequences. This opens up the possibility of more elaborate MRI studies of speech including spectral analysis of the speech signal in all types of MRI.

Acoustics↗
PubMed1981

The effect of sarcomere non-uniformity on the sarcomere length-tension relationship of skinned fibers.

It has proved difficult to activate skinned muscle fibers to produce high tension (3 kg/cm2 level) without loss of clear striations. A new method was developed which permits high tension production in skinned muscle fibers while retaining clear striations. Clear striations allow reliable measurement of the sarcomere lengths during contraction by microscopy and diffractometry. The method is to increase the Ca++ concentration of the bathing solution very gradually over a time period of 5 to 10 minutes. Once the skinned fiber is conditioned by this slow activation, subsequent contractions can be elicited by ordinary quick activations without loss of striations. When the experiments are carried out with careful controls for the uniformity of the sarcomere length distribution along the entire length of the fiber, contractions are highly repeatable. Using the new method and stringent quality control of fibers, the sarcomere length-isometric tension relationship of skinned rabbit soleus fibers was obtained. The results differ from those previously obtained by conventional activation methods in that tension increases with sarcomere length not only at low (pCa = 5.8), but also at high (pCa = 5.2), calcium concentration.

Animals↗
PubMed2000

[Phytotoxic effect of soil cadmium pollution on ramie].

A microplot locating experiment was conducted to study the phytotoxic effect of adding Cd in soil on ramie plants. The results showed that the contents of chlorophyll a and b of leaf, and the photosynthesis productivity of ramie plant were significant reduced by the addition of Cd. As the content of soil Cd reached to 14 mg.kg-1, the biomass yield of the above-ground part of ramie plants was 20% lower than the control, and was 50% lower when soil Cd content was at 100 mg.kg-1. The number of effective tillers was a main factor affecting the yield of ramie raw fibers, and Cd addition had a relatively small effect on the quality of raime fibers. It is suggested that a synthetical technology of soil treatment and agronomic measures should be applied to eliminate the toxic effect of soil Cd and to enhance the resistance of plant against soil Cd pollution when employing ramie as the alternative of food and vegetable crops in a Cd-polluted region, which is also important for a higher yield of ramie.

Biomass↗