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Compound heterozygosity for a Wolman mutation is frequent among patients with cholesteryl ester storage disease Texte intégral
2000
Peter Lohse | Sylke Maas | Pia Lohse | Milan Elleder | Jean M. Kirk | Guy T.N. Besley | Dietrich Seidel
Cholesteryl ester storage disease and Wolman disease are rare autosomal recessive lipoprotein-processing disorders caused by mutations in the gene encoding human lysosomal acid lipase. Thus far we have elucidated the genetic defects in 15 unrelated CESD patients. Seven were homozygotes for the prevalent hLAL exon 8 splice junction mutation which results in incomplete exon skipping, while eight probands were compound heterozygotes for E8SJM and a rare mutation on the second chromosome. In this report, we describe the molecular basis of CESD in three compound heterozygous subjects of Czech and Irish origin. RFLP and DNA sequence analysis revealed that they were heteroallelic for the common G934→A substitution in exon 8 of the hLAL gene and a mutation which, if inherited on both alleles, would be expected to result in complete loss of enzyme activity and to cause Wolman disease. In patients A. M. and J. J., two nucleotide deletions in exons 7 and 10 were detected, involving a T at position 722, 723, or 724 and a G in a stretch of five guanosines at positions 1064–1068 of the hLAL cDNA. Both mutations result in premature termination of protein translation at residues 219 and 336, respectively, and in the production of truncated, inactive enzymes. Subject D. H., in contrast, is a compound heterozygote for the Arg44→Stop mutation previously described in a French CESD proband. Combined with data in the literature, our results demonstrate that compound heterozygosity for a mutation causing Wolman disease is common among cholesteryl ester storage disease patients. —Lohse, P., S. Maas, P. Lohse, M. Elleder, J. M. Kirk, G. T. N. Besley, and D. Seidel. Compound heterozygosity for a Wolman mutation is frequent among patients with cholesteryl ester storage disease.
Afficher plus [+] Moins [-]Mise au point d' un biofongicide a base de talc utilisant Trichoderma harzianum et son effet sur la maladie du pourrissement de la racine du murier.
2000
Philip T. | Sharma D.D. | Govindaiah
Root rot disease of mulberry caused by Fusarium solani and F. oxysporum is a major problem in many sericultural areas of India. The disease causes sudden leaf withering, defoliation and death of plants. Efforts have been made to control the disease biologically. The efficacy of a bioformulation of Trichoderma harzianum grown on potato-yeast-sugar media and delivered into soil through talc as the base material, against the disease, the survival of pathogens and the biocontrol agent in the soil and the shelf life of the bioformulation have been investigated. In the talc based bioformulation, there was 40 and 110.10(6) colony forming units/gram after 90 days of storage at room temperature and in a refrigerator (4 degrees C) respectively. In the field the bioformulation helped to reduce the population of F. solani and F. oxysporum by about 85/ and it has controlled the disease by about 75/. There was no significant reduction in the efficiency of the bioformulation to control the disease even after 90 days of storage at room temperature. The efficacy of the product can be attributed to the rhizosphere competence of Trichoderma which is known to produce active metabolites such as lytic enzymes, chitinase, glucanase, harziadinole and an antibiotic "trichodermin", which kill many soil pathogens.
Afficher plus [+] Moins [-]Development of a talc based biofungicide using Trichoderma harzianum and its effect on mulberry root rot disease | Mise au point d'un biofongicide à base de talc utilisant Trichoderma harzianum et son effet sur la maladie du pourrissement de la racine du mûrier
2000
Philip, T. ((Central Sericultural Research and Training Institute, Srirumpara (Inde))) | Sharma, D.D. | Govindaiah
Root rot disease of mulberry caused by Fusarium solani and F. oxysporum is a major problem in many sericultural areas of India. The disease causes sudden leaf withering, defoliation and death of plants. Efforts have been made to control the disease biologically. The efficacy of a bioformulation of Trichoderma harzianum grown on potato-yeast-sugar media and delivered into soil through talc as the base material, against the disease, the survival of pathogens and the biocontrol agent in the soil and the shelf life of the bioformulation have been investigated. In the talc based bioformulation, there was 40 and 110.10(6) colony forming units/gram after 90 days of storage at room temperature and in a refrigerator (4 degrees C) respectively. In the field the bioformulation helped to reduce the population of F. solani and F. oxysporum by about 85/ and it has controlled the disease by about 75/. There was no significant reduction in the efficiency of the bioformulation to control the disease even after 90 days of storage at room temperature. The efficacy of the product can be attributed to the rhizosphere competence of Trichoderma which is known to produce active metabolites such as lytic enzymes, chitinase, glucanase, harziadinole and an antibiotic "trichodermin", which kill many soil pathogens
Afficher plus [+] Moins [-]Control of storage insects as a means of limiting yam tuber fungal rots
2000
Morse, S. | Acholo, M. | McNamara, N. | Oliver, R.
Yam rots caused by fungal pathogens (mostly Fusarium spp.) are a major cause of storage losses, and previous work has shown that fungal lesions were only found if there was pre-existing physical damage to the tuber. The general perception is that damage inflicted in the field prior to storage is far more important in this regard than damage caused during storage, and this has led to much research directed at the minimisation of field damage with relatively little work on the amelioration of insect damage during storage. This study examined whether insect damage inflicted on yam tubers during storage in specialised barns is an important agent in the incidence of fungal disease. It was found that treatment of tubers with insecticide dust (Actellic 2% Dust; ai=pirimiphos-methyl) significantly reduced fungal infections resulting from insect attack during storage. In addition, physical damage acquired during harvest appeared to be ameliorated by the insecticide, resulting in significantly fewer fungal lesions. The results suggest that insecticide treatment of yam tubers prior to storage could provide a relatively cheap and effective means of preservation.
Afficher plus [+] Moins [-]Potato fungal diseases in the 20th century and possible development of their range
2000
Hausvater, E.(Vyzkumny Ustav Bramborarsky, Havlickuv Brod (Czech Republic))
Approximately a third of more than 30 fungal diseases cause significant economic losses. Distribution and importance of individual diseases had changed in the past. Potato late blight was the most serious problem. In the pre-war and post-war years, other economically dangerous disease was potato wart disease, in the 70ths and 80ths storage diseases caused serious losses and in the last decade diseases damaging tuber quality and appearance become more significant. At present, economic importance of diseases damaging tuber quality is increasing. This is connected with requirements of consumers, who prefer washed potatoes with smooth skin free of disease symptoms in transparent packs on market. In this regard, even more attention is paid to potato black scurf (Rhizoctonia solani) and potato silver scurf (Helminthosporium solani). Late blight (Phytophthora infestans) is a constant priority of fungal disease control. Changes in pathogen populations and oospore occurrence require an intensive research on disease epidemiology and control systems.
Afficher plus [+] Moins [-]Potato tuber necrotic ringspot disease occurring in Japan: its association with Potato virus Y necrotic strain Texte intégral
2000
Ohshima, K. | Sako, K. | Hiraishi, C. | Nakagawa, A. | Matsuo, K. | Ogawa, T. | Shikata, E. | Sako, N.
Unfamiliar necrotic symptoms on or within potato tubers of cultivars Nishiyutaka and Dejima were observed in Nagasaki prefecture, Japan, in 1992. Symptoms were typically on the surface of the tuber, which either protruded at first and then became sunken, or showed necrotic spots, with necrosis within the tubers. Symptoms sometimes appeared at harvesting but more often appeared after storage for several months. Investigations revealed that the causal agents of the disease were isolates of Potato virus Y necrotic strain (PVY(NTN)) and the disease was potato tuber necrotic ringspot disease (PTNRD), previously reported in Europe and Lebanon. Five potato cultivars were inoculated with an isolate from necrotic tubers. The highest percentage of progeny tubers showing PTNRD was found in cv. Nishiyutaka (23.3%). In contrast, cvs. Shimabara, Mayqueen, and Danshaku showed a low percentage of PTNRD. Additional potato tubers with PTNRD were also observed after storage of the tubers. To investigate the relatedness between isolates of PVY(NTN) and of necrotic strain PVN(N), previously isolated in Japan, Nishiyutaka was inoculated with an isolate of PNY(N), which also induced PTNRD. Nucleotide sequences of coat protein (CP) genes of six PVY(NTN) isolates were determined. The CPs were 267 amino acids in length, with a substitution of one or no amino acid among each of the six isolates. The phylogenetic relationship based on nucleotide sequences of CP genes showed that these six PVY(NTN) isolates clustered together with PYN(N) isolates. This is the first report of PTNRD caused by PVY(NTN) isolates in Asia.
Afficher plus [+] Moins [-]Adaptation of diffused light storage system for potato under mid-elevated condition
2000
Anon.
The study aimed to determine the efficiency of the DLS [diffused light storage] technology in comparison to the existing farmers storage practices in the mid-elevated areas which is generally a makeshift dark storage (DS) usually attached to or part of the farmers' houses. The first storage trial was conducted for 6 months during the period January to June 2000. Both the DLS and DS were loaded each with 750 kgs, Granola variety seed materials, which is the predominant variety in the area. Sprouting was observed to be faster inside the DLS wherein the seeds are ready for planting after 4 months of storage compared to the 6 months storage period in the DS. Sprouting percentage is also higher at 63 percent as compared to the 49 percent of the seeds in DS, this means increased planting materials for the farmers. As per the physical characteristics of the sprouts, DLS yields shorter (with an average of 1.1 cm length) and thicker (ave. of 0.63 cm) and dark green sprouts, which according to the cooperator makes them sturdier and easier to transplant as compared to the quality of the seeds stored in DS. Rotting incidence begins to be visible after 2 months of storage for both set-ups. Final estimate of the percentage of rotten tubers before it was planted is at 16 percent and 28 percent for DLS and DS, respectively. However, there was no significant observation of disease and pest infestation for both storages but the cooperator found it easy to monitor these parameters for seeds stored in DLS. Also, emergence of plants is faster by two weeks for seeds stored in DLS as compared to those stored in DS. With these initial findings, the technology supports the significant findings, experiences and viewpoints of its user in the highland
Afficher plus [+] Moins [-]Study On New Attenuated Strain (Sa) Of Theileria Annulata For Cattle Vaccination Against Bovine Theileriosis
2000
Hashemi Fesharaki , Reza
Theileriosis due to Theileria annulata is a dangerous and foetal disease for pure - bred and cross-bred cattle particularly exotic animals. The mortality rate is more than 80%. To protect these animals again st the disease and induce good immunity) two vaccine strains were previously used at an interval of 30-40 days. But because of difficulties in production) control) storage and transportation. of two vaccine strains) it was decided to use only one vaccine strain for vaccination. The study indicated that this new vaccine strain could induce good protective immunity in susceptible animals against acute Theileriosis without any side - effects. The animals particularly milking cows) tolerate the vaccine well. As a result they could resist foetal and acute strains of T. annulata
Afficher plus [+] Moins [-]Characteristics of denatured rapeseed oil during storage and refining processes Texte intégral
2000
M. V. Ruiz-Méndez | M. Posada de la Paz | B. Blount | H. Schurz Rogers | N. Castro-Molero | R. M. Philen
In 1981, toxic oil syndrome, a progressive multi-system disease caused by consumption of rapeseed oil denatured with aniline occurred in Spain. To date, the causal toxic agent or agents remain unknown. Measures of acidity, moisture, impurities, phosphorous, soaps, and spectrophotometric determinations of color at 409 nm were performed. Since fatty acid anilide concentrations in these oils are associated with risk of disease, w e studied the formation of aniline-derived compounds over time after oil denaturation and by oil deodorization temperatures (200ºC, 215ºC, 230ºC, 245ºC, 260ºC, y 270ºC) and times (3, 4, 4.5, 5, 5.5 and 6 hours). Formation of fatty acid anilide compounds increased with storage time. Deodorization led to a reduction of total anilides in all the samples, particularly at temperatures above 245ºC. Esters of 3-(N-phenylamino)-1,2-propanediol were not detected.
Afficher plus [+] Moins [-]Field reaction of cassava genotypes to anthranose, bacterial blight, cassava mosaic disease and their effects on yield Texte intégral
2000
Fokunang, C.N. | Ikotun, T. | Dixon, Alfred G.O. | Akem, C.N.
Thirteen cassava genotypes were evaluated at the International Institute of Tropical Agriculture, Ibadan, Nigeria for anthracnose (CAD), bacterial blight (CBB) and cassava mosaic disease (CMD) incidence and severity, and their effects on yield, for three consecutive planting seasons. There were significant differences (P<0.05) in CAD, CBB and CMD incidence and severity amongst the cassava genotypes across the planting seasons. Yield assessment showed significant differences (P<0.05) in storage root number, plant stand, root fresh weight and dry matter content among the cassava genotypes. There was no significant variation in tuber rot among the genotypes, and 80% of the genotypes did not show any tuber root rot when harvested 12 months after planting. CBB and CAD incidences were significantly and positively correlated (r=0.43), whereas CBB and CMD incidences were not significantly correlated (r=0.03). CAD and CMD incidence and severity were highly correlated (r=0.82 and r=0.76, respectively). CBB incidence was negatively correlated with storage root weight and fresh root tuber number (r=-0.45 and r=-0.48, respectively). CMD severity showed a significant negative correlation with storage root weight (r=0.44). Cassava genotypes TMS 30001, 30211 and 88/01087 showed a stable resistance over 3 planting seasons to CAD, CBB and CMD.
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