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91.
Diego A. Gomez Philip A. May Barbara G. Tabachnick Julie M. Hasken Elizabeth R. Lyden Wendy O. Kalberg H. Eugene Hoyme Melanie A. Manning Margaret P. Adam Luther K. Robinson Kenneth Lyons Jones David Buckley Omar A. Abdul‐Rahman 《American journal of medical genetics. Part A》2020,182(10):2243-2252
Fetal alcohol spectrum disorders (FASD) describe a range of physical, behavioral, and neurologic deficits in individuals exposed to alcohol prenatally. Reduced palpebral fissure length is one of the cardinal facial features of FASD. However, other ocular measurements have not been studied extensively in FASD. Using the Fetal Alcohol Syndrome Epidemiologic Research (FASER) database, we investigated how inner canthal distance (ICD), interpupillary distance (IPD), and outer canthal distance (OCD) centiles differed between FASD and non‐FASD individuals. We compared ocular measurement centiles in children with FASD to non‐FASD individuals and observed reductions in all three centiles for ICD, IPD, and OCD. However, when our non‐FASD children who had various forms of growth deficiency (microcephaly, short‐stature, or underweight) were compared to controls, we did not observe a similar reduction in ocular measurements. This suggests that reductions in ocular measurements are a direct effect of alcohol on ocular development independent of its effect on growth parameters, which is consistent with animal models showing a negative effect of alcohol on developing neural crest cells. Interpupillary distance centile appeared to be the most significantly reduced ocular measure we evaluated, suggesting it may be a useful measure to be considered in the diagnosis of FASD. 相似文献
92.
In vitro degradation of silk fibroin 总被引:14,自引:0,他引:14
Horan RL Antle K Collette AL Wang Y Huang J Moreau JE Volloch V Kaplan DL Altman GH 《Biomaterials》2005,26(17):3385-3393
A significant need exists for long-term degradable biomaterials which can slowly and predictably transfer a load-bearing burden to developing biological tissue. In this study Bombyx mori silk fibroin yarns were incubated in 1mg/ml Protease XIV at 37 degrees C to create an in vitro model system of proteolytic degradation. Samples were harvested at designated time points up to 12 weeks and (1) prepared for scanning electron microscopy (SEM), (2) lyophilized and weighed, (3) mechanical properties determined using a servohydraulic Instron 8511, (4) dissolved and run on a SDS-PAGE gel, and (5) characterized with Fourier transform infrared spectroscopy. Control samples were incubated in phosphate-buffered saline. Fibroin was shown to proteolytically degrade with predictable rates of change in fibroin diameter, failure strength, cycles to failure, and mass. SEM indicated increasing fragmentation of individual fibroin filaments from protease-digested samples with time of exposure to the enzyme; particulate debris was present within 7 days of incubation. Gel electrophoresis indicated a decreasing amount of the silk 25 kDa light chain and a shift in the molecular weight of the heavy chain with increasing incubation time in protease. Results support that silk is a mechanically robust biomaterial with predictable long-term degradation characteristics. 相似文献
93.
Paul K. Hildebrandt James D. Conroy Adam E. McKee M. B. A. Nyindo David L. Huxsoll 《Infection and immunity》1973,7(2):265-271
The ultrastructure of Ehrlichia canis was examined in both pulmonary mononuclear cells and in monocytes cultured from an infected dog. The cytoplasmic inclusions, or morulae, of E. canis consisted of a membrane-lined vacuole-containing elementary bodies which varied in size and number. The elementary bodies were bound by two trilamellar membranes. The organism shared morphological properties of both the genus Rickettsia and genus Chlamydia. 相似文献
94.
Jones HE Andolina IM Oakely NM Murphy PC Sillito AM 《Experimental brain research. Experimentelle Hirnforschung. Expérimentation cérébrale》2000,135(2):279-284
We have compared the spatial summation characteristics of cells in the primary visual cortex with those of cells in the dorsal lateral geniculate nucleus (LGN) that provide the input to the cortex. We explored the influence of varying the diameter of a patch of grating centred over the receptive field and quantitatively determined the optimal summation diameter and the degree of surround suppression for cells at both levels of the visual system using the same stimulus parameters. The mean optimal summation size for LGN cells (0.90 degrees) was much smaller than that of cortical cells (3.58 degrees). Virtually all LGN cells exhibited strong surround suppression with a mean value of 74%+/-1.61% SEM for the population as a whole. This potent surround suppression in the cells providing the input to the cortex suggests that cortical cells must integrate their much larger summation fields from the low firing rates associated with the suppression plateau of the LGN cell responses. Our data suggest that the strongest input to cortical cells will arise from geniculate cells representing areas of visual space located at the borders of a visual stimulus. We suggest that analysis of response properties by patterns centred over the receptive fields of cells may give a misleading impression of the process of the representation. Analysis of pattern terminations or salient borders over the receptive field may provide much more insight into the processing algorithms involved in stimulus representation. 相似文献
95.
The complete sequence of the coding region of the ATM gene reveals similarity to cell cycle regulators in different species 总被引:30,自引:3,他引:30
Savitsky Kinneret; Sfez Sharon; Tagle Danilo A.; Ziv Yael; Sartiel Adam; Collins Francis S.; Shiloh Yosef; Rotman Gallt 《Human molecular genetics》1995,4(11):2025-2032
Ataxia-telangiectasia (A-T) is an autosomal recessive disorderinvolving cerebellar degeneration, immunodeficiency, radiationsensitivity, and cancer predisposition. A-T heterozygotes aremoderately cancer prone. The A-T gene, designated ATM, was recentlyidentified in our laboratory by positional cloning, and a partialcDNA clone was found to encode a polypeptide with a PI-3 kinasedomain. We report here the molecular cloning of a cDNA contigspanning the complete open reading frame of the ATM gene. Thepredicted protein of 3056 amino acids shows significant sequencesimilarities to several large proteins in yeast, Drosophilaand mammals, all of which share the PI-3 kinase domain. Manyof these proteins are involved in the detection of DNA damageand the control of cell cycle progression. Mutations in theirgenes confer a variety of phenotypes with features similar tothose observed in human A-T cells. The complete sequence ofthe ATM gene product provides useful clues to the function ofthis protein, and furthers understanding of the pleiotropicnature of the A-T mutations. 相似文献
96.
H. Seibold E. Henze J. Kohler J. Roth A. Schmidt W. Adam 《Journal of molecular medicine (Berlin, Germany)》1985,63(20):1041-1047
Summary Simultaneous right heart catheterization and radionuclide ventriculography were performed in 27 patients with a wide range of chronic obstructive pulmonary disease. Central hemodynamics and radionuclide studies were done at rest and during exercise. In the resting state the right ventricular ejection fraction (RVEF) was in the normal range (43.3±6%). During exercise a significant (p<0.001) decrease of RVEF to 38.8±6.7% occurred. The pumonary artery mean pressures were 19.9±3.8 at rest. During exercise a significant (p<0.001) increase to 41±9.8 mm Hg occurred. There was a linear relationship between pulmonary pressures and RVEF during exercise in patients with pulmonary artery pressures not exceeding 35 mm Hg. In patients with right ventricular end-diastolic wall thickness 6 mm a curvilinear relationship between these parameters could be observed with a flattening of the curve at higher pressures (>35 mm Hg) and lower ejection fractions (<35% RVEF). Radionuclide venticulography cannot substitute for right heart catheterization. Echocardiography is useful for interpretation of right ventricular ejection fractions in advanced chronic obstructive pulmonary disease.Abbreviations CI
Cardiac index (l/min/m2)
- CO
Cardiac output (l/min)
- COPD
Chronic obstructive pulmonary disease
- FEV1
Forced expiratory volume in the first second (ml)
- HR
Heart rate (B/min)
- PAd
Pulmonary artery diastolic pressure (mm Hg)
- PAP
Pulmonary artery mean pressure (mm Hg)
- PAs
Pulmonary artery peak pressure (mm Hg)
- PVR
Pulmonary vascular resistance (dyn·s·cm–5)
- PwP
Pulmonary capillary wedge pressure (mm Hg)
- RAP
Right arterial pressure (mm Hg)
- Raw
Airway resistance (cm H2/l/s)
- RNV
Radionuclide ventriculogram
- RV
Residual volume (l)
- RVEF
Right ventricular ejection fraction (%)
- RVEDVI
Right ventricular enddiastolic volume index (ml/m2)
- RVEDVI
SVI RVEF (ml/m2)
- RVESVI
Right ventricular endsystolic index (m2/m2)
- SVI
Stroke volume index (ml/m2)
- TLC
Total lung capacity (l)
- VC
Vital capacity (l) 相似文献
97.
Pelisek J Engelmann MG Golda A Fuchs A Armeanu S Shimizu M Mekkaoui C Rolland PH Nikol S 《Journal of molecular medicine (Berlin, Germany)》2002,80(11):724-736
Cationic liposomes/DNA complexes are widely used vectors for delivering genes in clinical and experimental trials. Relatively low transfer efficiencies in vivo compared with viral gene transfer may be improved using local application. In addition, markedly increased transfer efficiency may be achieved in vitro and in vivo via optimization of known variables influencing liposomal transfection. Lipofection under different conditions was performed in various cell lines and primary porcine smooth muscle cells. Optimized conditions found in vitro were verified in vivo using a porcine restenosis model. Toxicity was monitored analyzing cell metabolism. Transfer efficiency and safety were determined using morphometry, histology, galactosidase assays, PCR, and RT-PCR. The most important variables enabling maximum transfer efficiency were firstly the appropriate selection of cationic lipids for the cell type to be transfected, secondly the DNA/liposome ratio chosen, which depended on the cell type and cationic lipids used, and thirdly the state of proliferation of the targeted cells. Transfection in vivo demonstrated two- to fivefold higher transfer efficiencies when transfer conditions were extrapolated from optimization experiments in stationary cells compared with the use of conditions established in proliferating cells. Application of the therapeutic gene for cecropin using optimized transfer conditions resulted in a significantly reduced neointima formation compared with the transfection using a control gene for ss-galactosidase. Thus, in this vascular model, initial optimization of lipofection in stationary cells in culture followed by local delivery in vivo and with selection of a suitable therapeutic gene led to markedly improved transfer efficiencies, gene expression, and biological effect. Stationary cell cultures simulate more realistically the in vivo situation and may therefore represent a better model for future in vivo experiments. In addition, the advantages of liposomes are easy handling, low toxicity, and the lack of carcinogenicity or immunogenic reactions. 相似文献
98.
99.
Fast implementation of the single scatter simulation algorithm and its use in iterative image reconstruction of PET data 总被引:1,自引:0,他引:1
In positron emission tomography (PET), scatter correction is usually performed prior to image reconstruction using a more or less exact model of the scatter processes. These models require estimates of the true activity and object density distributions of the imaged object. The problem is that these estimates are computed from measured data and, therefore, already contain scattered events. The purpose of this work was to overcome this problem by incorporating scatter characteristics directly into the process of iterative image reconstruction. This could be achieved by an optimized implementation of the single scatter simulation (SSS) algorithm, which results in a significant speed-up of the scatter estimation procedure. The scatter simulation was then included in the forward projection step of maximum likelihood image reconstruction. The results demonstrate that this approach leads to a more exact estimation of the scatter component which cannot be obtained by a simple sequential data processing strategy. 相似文献
100.
The ribosomal DNA from the Zygomycete Mucor miehei has been characterised. The complete rDNA unit was cloned by heterologous PCR using primers whose sequence matched conserved
regions of the rDNA from related fungal species. The sequence of the overlapping PCR products revealed the existence of a
repeated unit of 9574 bp. The genes encoding the different rRNA species were identified by their homology to the corresponding
sequences from other fungi. We estimate that the rDNA unit is present in the genome of M. miehei in about 100 copies. This estimation was made by comparing the intensity of its hybridisation signal in a Southern blot with
that of the mmp gene coding for aspartyl protease, which was assumed to be contained in single copy. The size and structure of the M. miehei rDNA unit was similar to that of other fungi. The genes encoding the 25S, 18S and 5.8S RNAs are closely linked within the
repeated unit which also contains the 5S gene. This latter gene appears to be transcribed in the opposite direction. The 25S,
18S and 5.8S genes showed 70–80% homology to the corresponding genes from other fungi, whereas the degree of homology for
the 5S gene was much lower. The highest homology (about 80%) corresponded to the few available sequences from other Mucor species. Homology to genes from other Zygomycota was no higher than that observed for genes from the Ascomycota or Basidiomycota fungi.
Received: 21 December 1999 / 1 March 2000 相似文献