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111.
We demonstrate that basic components of the plastid protein-import apparatus originally found in pea, Toc34, Toc159, and Tic110, are also conserved in evolutionarily younger gymnosperms. We show that multiple isoforms of the preprotein receptor Toc34 differentially accumulate in various stages of needle development, while the amounts of Toc159 drastically decrease during chloroplast morphogenesis. Spruce Toc34 and Toc159 receptors are able to recognise and interact with the angiosperm precursor of the Rubisco small subunit. Young proplastids found in closed buds contain a highly elevated number of protein translocation complexes equipped with only two types of outer envelope receptors, Toc159 and a 30-kDa Toc34-related protein. Photosystem II (PSII) can already be assembled in a fully functional complex at this very early stage of needle development, suggesting that no additional receptor isoforms are needed for translocation of all necessary PSII components. We conclude that the accumulation of evolutionarily conserved plastid preprotein translocation components is differentially regulated during spruce needle development.  相似文献   
112.
In this study, the activity of nuclear phosphatidylinositol-specific phosholipase C (PI-PLC) was investigated in HL-60 cells blocked at G(2)/M phase by the addition of nocodazole, and released into medium as synchronously progressing cells. Two peaks of an increase in the nuclear PI-PLC activities were detected; an early peak reached a maximum at 1 h after release from the nocodazole block, and a second increase was detected at 8.5 h after the release. Immunoprecipitation studies indicated that the increase in the activity was due to the activation of the nuclear PI-PLC-beta(1). Western blot analysis demonstrated no changes in the level of both a and b splicing variants of PI-PLC-beta(1) in the nuclei of cells isolated at either 1 h or 8.5 h after the block. However, an increase in the serine-phosphorylation of PI-PLC-beta(1b) was detected in the nuclei of HL-60 cells isolated at 1 and 8.5 h after the block, and the presence of MEK-inhibitor PD98059 completely inhibited both the serine phosphorylation and the increase in the PI-PLC activities in vitro. The presence of PI-PLC inhibitor prevented the progression of HL-60 cells through the G(1) into S phase of the cell cycle. These results demonstrate that two peaks of nuclear PI-PLC activities, which are due to a PD98059-sensitive phosphorylation of nuclear PLC-beta(1b) on serine, occur at the G(2)/M and late G(1) phase and are necessary for the progression of the cells through the cell cycle.  相似文献   
113.
The aim of this paper is to present the post mortem dental evidence and dental health of the victims exhumed throughout the territories of Croatia that was temporarily occupied during the war. A total number of 62,432 teeth out of 1,253 human bodies exhumed from 5 different counties were analyzed. The majority of victims inhabited those areas before 1991. Post mortem dental characteristics were analyzed according to the American Board of Forensic Odontology and WHO methodology. The results show the highest level of the dental health before 1991 in the Vukovarsko-Srijemska County. The decayed (D), missing (M), filling (F), teeth (T), DMFT of that County was at the lowest level i.e. at 5.2. In all of the other counties, it was always between 6 and 12. The material most frequently used for the dental fillings was amalgam. Its highest frequency level was recorded in the County 4 (8%) and lowest in the County 1 (1.5%), p<0.001. The most frequent prosthodontic appliances were acrylic dentures. Their frequency was lowest in the County 5 (1.3%) and highest in the County 3 (11.6%), p<0.001. Determination of sex and dental age showed that victims were mostly men (79%) of middle and elderly age (89%). Teeth were useful also for monitoring of the quality of exhumations--taking into consideration number of empty dental sockets. The highest number of empty dental sockets was recorded in the County 3 (40.4%) and lowest in the County 1 (13.5%), p<0.001. Even after many years in the soil, teeth proved to be the most preserved human organs and valuable indicators of identity as well as of the way of life before death.  相似文献   
114.
Between January 1st 1990 and December 31st 1999, 24 patients affected by Klatskin tumor underwent operation in our department of surgery. According to Bismuth's classification, there were 0 (0%) type I, 5 (21%) type II, 6 (25%) type IIIa, 4 (17%) type IIIb and 9 (37%) type IV tumors. Five patients (21%) were treated by curative resection (group I) while in 14 patients (58%) palliative surgical procedure was performed (group II). In 5 cases (21%) the extension of malignancy did not allowed any procedure (group III). Curative resection for malignant tumors of the hepatic duct bifurcation included wide tumor excision and bile duct resection at the liver hilum (with wedge hepatic resection in one patient) and creation of biliary-enteric anastomosis. Palliative surgical procedure included stent insertion. Jaundice was completely relieved in all patients undergoing resection, since 3 patients (21%) after stenting hadn't satisfactory biliary drainage. There was 1 (20%) perioperative death in the group 1, while in group 2, 5 patients (36%) died postoperatively. In this series, the mean postoperative survival of all patients was 16 months. The mean postoperative survival of patients undergoing localized tumor resection with curative intent was 38 months, in contrast to 10 months for those undergoing operative stent insertion. in addition, only 1 patient from group III, in whom only exploratory surgery were performed survived 7 months, while other 4 patients died in the hospital. This retrospective review suggests that aggressive surgical treatment could improve survival and quality of life in patients suffering from Klatskin tumor.  相似文献   
115.
The survey aimed to determine the reasons for extraction of permanent teeth by general dental practitioners in urban and rural population of the Senj region, Adriatic coast, Croatia. During a two-year period (1998-9), a total of 2006 teeth were extracted in both regions, in patients aged 15+. The causes were defined as follows: (1) decay or root without a crown (radix relicta), (2) periodontal disease, (3) endodontic or periapical diseases and (4) other reasons--orthodontics/prosthodontics and dental trauma. The statistical Chi-square-test was used to determine the significant difference between the populations and the sexes. Dental caries was the most frequent cause for extraction (over 50%), followed by endodontic and periapical diseases (23%) as the result of untreated caries and at the end periodontal disease (21%). Urban population more often lose teeth due to periodontal disease (22.75%) than rural (18.93%, p < 0.05). Similarly, this is more frequent in the urban male population (25.61%) than the female urban population (20%, p < 0.05). In rural areas, people more often lost teeth as a result of endodontic and periapical disease (25.85%) than in the urban locations (19.07%, p < 0.01) and this is more frequent in women from rural areas (28.37%) than the rural men (22.44%, p < 0.05). Periodontal disease was not the main cause of tooth loss in either the rural or the urban population. Dental caries and its sequel remain the most important challenge for the dental service. It also reveals the inadequacy of dental services. Education of both the population and the general dental practitioners must be conducted in order to improve oral hygiene and to insist on conservative rather than extraction therapy.  相似文献   
116.
The activity of nuclear phosphoinositide 3-kinase C2beta (PI3K-C2beta) was investigated in HL-60 cells induced to differentiate along granulocytic or monocytic lineages. A significant increase in the activity of immunoprecipitated PI3K-C2beta was observed in the nuclei and nuclear envelopes isolated from all-trans-retinoic acid (ATRA)-differentiated cells which was inhibited by the presence of PI3K inhibitor LY 294002. High-performance liquid chromatography analysis of inositol lipids showed an increased incorporation of radiolabelled phosphate in both PtdIns(3)P and PtdIns(3,4,5)P(3) with no changes in the levels of PtdIns(4)P, PtdIns(3,4)P(2) and PtdIns(4,5)P(2). Western blot analysis of the PI3K-C2beta immunoprecipitates with anti-P-Tyr antibody revealed a significant increase in the level of the immunoreactive band corresponding to PI3K-C2beta in the nuclei and nuclear envelopes isolated from ATRA-differentiated cells.  相似文献   
117.

Background

Biotin-thiamine responsive basal ganglia disease is a severe, but potentially treatable disorder caused by mutations in the SLC19A3 gene. Although the disease is inherited in an autosomal recessive manner, patients with typical phenotypes carrying single heterozygous mutations have been reported. This makes the diagnosis uncertain and may delay treatment.

Methods and Results

In two siblings with early-onset encephalopathy dystonia and epilepsy, whole-exome sequencing revealed a novel single heterozygous SLC19A3 mutation (c.337T>C). Although Sanger-sequencing and copy-number analysis revealed no other aberrations, RNA-sequencing in brain tissue suggested the second allele was silenced. Whole-genome sequencing resolved the genetic defect by revealing a novel 45,049 bp deletion in the 5’-UTR region of the gene abolishing the promoter. High dose thiamine and biotin therapy was started in the surviving sibling who remains stable. In another patient two novel compound heterozygous SLC19A3 mutations were found. He improved substantially on thiamine and biotin therapy.

Conclusions

We show that large genomic deletions occur in the regulatory region of SLC19A3 and should be considered in genetic testing. Moreover, our study highlights the power of whole-genome sequencing as a diagnostic tool for rare genetic disorders across a wide spectrum of mutations including non-coding large genomic rearrangements.  相似文献   
118.
119.
From a genetic standpoint, Streptomyces rimosus is arguably the best-characterized industrial streptomycete as the producer of oxytetracycline and other tetracycline antibiotics. Although resistance to these antibiotics has reduced their clinical use in recent years, tetracyclines have an increasing role in the treatment of emerging infections and noninfective diseases. Procedures for in vivo and in vitro genetic manipulations in S. rimosus have been developed since the 1950s and applied to study the genetic instability of S. rimosus strains and for the molecular cloning and characterization of genes involved in oxytetracycline biosynthesis. Recent advances in the methodology of genome sequencing bring the realistic prospect of obtaining the genome sequence of S. rimosus in the near term.  相似文献   
120.
Hemophilia A is an inherited bleeding disorder characterized by factor VIII deficiency. The basis for insufficient hemostasis lies within inadequate amplification of factor Xa production with the undersupplied factor VIII. We report on a young patient with critical aortic stenosis bearing all the clinical stigmata of severe hemophilia, in whom aortic valve replacement was performed with a tissue valve in order to avoid the need for long term anticoagulation.  相似文献   
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