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1.
Leukemia inhibitory factor (LIF) is locally up-regulated after peripheral nerve injury and may be involved in the subsequent regeneration. Here, adult mice with or without LIF gene deletions were used to study the role of LIF in regeneration. The results show that axonal regeneration in vitro from dorsal root ganglia (DRGs) was unaffected by LIF deletion. However, segments from wild type mice promoted DRG axonal outgrowth better than segments from LIF deleted animals when in vivo-injured sciatic nerve segments were co-cultured with DRGs from normal adult mice. Addition of LIF could not restore the deficit. This suggests that LIF is engaged in the local regulation of regeneration but not in the regenerative events occuring at the cell body level.  相似文献   
2.
The most apical 2 mm of the root canals of periapically diseased roots were examined for microorganisms by scanning electron microscopy (SEM). Bacteria in this area were observed in 10 out of 12 (83.3%) cases. The two remaining cases exhibited bacteria more coronally, with tissue remnants between the bacterial front and the apical foramen. Rod-shaped bacteria dominated, but filaments, spirochetes and cocci were also seen. Cocci and rods sometimes formed micro-colonies. Occasionally, cocci were seen attached to filaments forming "corn-cob"-like structures. Deposits resembling bacterial plaque were also found inside the root canal. SEM is useful for studying microbial topography of the apical root canal.  相似文献   
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Arterial stiffness (Ast) individually predicts cardiovascular (CV) mortality. Ast increases via vascular calcification and can be characterized by pulse wave velocity (PWV). We assessed the influence of mineral and bone metabolism on Ast in dialyzed (D) and renal transplanted (Tx) children by measuring fetuin-A and bone markers [bone-specific alkaline phosphatase (BALP); beta-CrossLaps (β)]. Normalized PWV/height (PWV/h) of 11 D and 17 Tx patients was measured by applanation tonometry. Levels of calcium (Ca), phosphate (P), fetuin-A, and bone markers were analyzed. Ca × P/fetuin-A ratio was calculated to characterize the balance of calcification and inhibition. Cumulative dose of calcitriol was also assessed. Fetuin-A was lower in D and Tx compared with healthy controls. Bone markers and Ca × P/fetuin-A of D were significantly higher than those of Tx and controls. In D PWV/h correlated with Ca × P/fetuin-A and BALP (r = 0.8; p = 0.005, r = 0.6, p = 0.05, respectively); BALP correlated with Ca × P/fetuin-A (r = 0.7, p = 0.01). In Tx, there was a correlation between calcitriol administered before transplantation and PWV/h (r = 0.5, p = 0.04). Increased bone turnover was coupled with an increased potential of calcium-phosphate precipitation, as shown by the increased Ca × P/fetuin-A. It might explain the connection between disturbed mineral and bone metabolism and Ast. Tx might be beneficial on Ast, though follow-up studies are needed.  相似文献   
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The systemic host defence mechanisms, especially innate immunity, in venous leg ulcer patients are poorly investigated. The aim of the current study was to measure Candida albicans killing activity and gene expressions of pro‐ and anti‐inflammatory cytokines and innate immune response regulators, TAM receptors and ligands of peripheral blood mononuclear cells separated from 69 venous leg ulcer patients and 42 control probands. Leg ulcer patients were stratified into responder and non‐responder groups on the basis of wound healing properties. No statistical differences were found in Candida killing among controls, responders and non‐responders. Circulating blood mononuclear cells of patients overexpress pro‐inflammatory (IL‐1α, TNFα, CXCL‐8) and anti‐inflammatory (IL‐10) cytokines as well as TAM receptors (Tyro, Axl, MerTK) and their ligands Gas6 and Protein S compared with those of control individuals. IL‐1α is notably overexpressed in venous leg ulcer treatment non‐responders; in contrast, Axl gene expression is robustly stronger among responders. These markers may be considered as candidates for the prediction of treatment response among venous leg ulcer patients.  相似文献   
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A second-generation 5000 rad radiation hybrid (RH) map of the cattle genome was constructed primarily using cattle ESTs that were targeted to gaps in the existing cattle-human comparative map, as well as to sparsely populated map intervals. A total of 870 targeted markers were added, bringing the number of markers mapped on the RH(5000) panel to 1913. Of these, 1463 have significant BLASTN hits (E < e(-5)) against the human genome sequence. A cattle-human comparative map was created using human genome sequence coordinates of the paired orthologs. One-hundred and ninety-five conserved segments (defined by two or more genes) were identified between the cattle and human genomes, of which 31 are newly discovered and 34 were extended singletons on the first-generation map. The new map represents an improvement of 20% genome-wide comparative coverage compared with the first-generation map. Analysis of gene content within human genome regions where there are gaps in the comparative map revealed gaps with both significantly greater and significantly lower gene content. The new, more detailed cattle-human comparative map provides an improved resource for the analysis of mammalian chromosome evolution, the identification of candidate genes for economically important traits, and for proper alignment of sequence contigs on cattle chromosomes.  相似文献   
9.

Objective

To explore the links between neurodevelopmental disorders – attention deficit hyperactivity disorder (ADHD) and autism spectrum disorder (ASD) – and personality in a population-based, genetically sensitive study of children.

Method

A population-based sample of 1886 twins aged 9 and 12, enriched for childhood mental health problems, was recruited from the Child and Adolescent Twin Study in Sweden (CATSS). Parents were interviewed over the telephone using the Autism-Tics, AD/HD and other Comorbidities (A-TAC) inventory, and in a second step they rated their children according to the Junior Temperament and Character Inventory (JTCI).

Results

ADHD was strongly correlated with novelty seeking, while ASD was correlated positively with harm avoidance and negatively with reward dependence. The strongest associations between personality traits and neurodevelopmental disorders were negative correlations between the character dimensions of self-directedness and cooperativeness and ADHD and ASD alike. Cross-twin cross-trait correlations between ADHD, ASD, and personality dimensions in monozygotic twins were more than double those in dizygotic twins, indicating a strong genetic effect behind the phenotypic covariation between neurodevelopmental disorders and personality.

Conclusions

Neurodevelopmental disorders are linked specifically to particular temperament profiles and generally to hampered development of the self-governing strategies referred to as “character.” Poor self-agency and cooperation may be core functional outcomes in the separation of children with handicapping conditions from those with traits only reminiscent of neurodevelopmental disorders. The associations between neurodevelopmental disorders and personality are at least partly due to genetic effects influencing both conditions. As a consequence, personality must be broadly considered in neuropsychiatry, just as neuropsychiatric disorders and their genetic, neurodevelopmental, and cognitive susceptibilities have to be in personality research and clinical treatment.  相似文献   
10.
By comparing the incidence of cystoid macular edema (CME) in three groups of patients having different surgical procedures, we attempted to assess the role of vitreous loss as a risk factor for CME development. In the first group (n = 470), the surgical procedure was extracapsular cataract extraction followed by implantation of posterior chamber lens (EC-CE + PC-IOL). The second group (n = 42) had extracapsular cataract extraction which was complicated by posterior capsule rupture, and therefore anterior vitrectomy followed by implantation of anterior chamber lens had to be performed (ECCE + anterior vitrectomy + AC-IOL). In the third group (n = 22) the surgery was intracapsular cataract extraction followed by anterior chamber lens implantation (ICCE + AC-IOL). The third group was included in this follow up study to assess the role of AC-IOL as a possible causative factor for development of CME in uncomplicated cases of ICCE and AC-IOL. The difference of incidences of CME in the second and third group would therefore depend mostly on the vitreous loss. The incidence of CME diagnosed by fluorescein angiography in the first, second and third group was 1.5% (7/470), 35.7% (15/42) and 9.0% (2/22), respectively. All patients who developed CME were treated with combination of corticosteroid-antibiotic drops, dexamethasone retrobulbarly (40 mg/day) and peroral indomethacine (25 mg/day/6 weeks). This therapeutic regime resulted in only moderate improvement of visual acuity.Abbreviations AC-IOL anterior chamber intraocular lens - CME cystoid macular edema - ECCE extracapsular cataract extraction - ICCE intracapsular cataract extraction - IOL intraocular lens - PC-IOL posterior chamber intraocular lens  相似文献   
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