Functional characterization of mouse lymphocyte subpopulations identified by their natural binding of bacteria. II. Identification of subpopulations of LY-1 + 2-3-, LY-1-2+3+ and LY-1+2+3+ cells and the localization of specific cytotoxic cells in a subset of LY-1-2+3+ cells .

Three T-cell subpopulations (T1, T2 and T3) can be identified by their binding of various bacteria (Mayer, Chen, Dray & Teodorescu, 1978). In this work we determined how the three subpopulations identified by their Ly-1, -2 and -3 alloantigens were distributed among the T1, T2 and T3 subpopulations. We found that the T1 subpopulation contained most of the Ly-1+2+3+ cells, that the T2 subpopulation contained some Ly-1+2-3- and some Ly-1-2+3+ cells and that the T3 subpopulation contained the remainder of the Ly-1+2+3+, Ly-1+2-3- and Ly-1-2+3+ cells. Thus the subpopulations identified by their bacterial adherence properties subdivided the three subpopulations identified by their Ly-1, -2 and -3 alloantigens. We also investigated whether the specific cytotoxic T lymphocytes were contained in the T1, T2 and/or T3 cells. We found that essentially all of the cytotoxic T lymphocytes were contained in the T3 subpopulation. Since the T3 cells contained a subpopulation of Ly-1-2+3+ cells the data indicated that essentially all of the cytotoxic T lymphocytes were contained in a subpopulation of Ly-1-2+3+ cells.     

Differences in the phagocytosis of four bacteria by channel catfish neutrophils

The purpose of this study was to compare the phagocytosis of Aeromonas hydrophila, Edwardsiella ictaluri, Edwardsiella tarda and Micrococcus luteus by channel catfish neutrophils. Various aspects of opsonization effect and bactericidal ability of channel catfish neutrophils were investigated. Percent phagocytosis ranged from a low of 1% to a high of 91%. The highest percent phagocytosis and phagocytic indices routinely occurred with normal serum and were highest for M. luteus (91.78%, 55.25) and A. hydrophila (87.52%, 43.60). In all cases, the percent phagocytosis and phagocytic index was lowest in assays without serum. Channel catfish neutrophils displayed a bactericidal/static ability for each bacterium tested except E. tarda. Neutrophils exhibited a greater inhibitory capacity for A. hydrophila and M. luteus than for the other bacteria when in the presence of normal or inactivated catfish serum.     

The light microscopic localization of substance P- and somatostatin-like immunoreactive cells in the larval tiger salamander retina

Summary Light microscopic immunocytochemistry was utilized to localize the populations of substance P (SP)- and somatostatin (SOM)-like immunoreactive cells in the larval tiger salamander retina. Of 104 SP-immunostained cells observed, 82% were Type 1 amacrine cells. Another 8% of the SP-cells were classified as Type 2 amacrine cells, while 10% of the SP-cells had their cell bodies located in the ganglion cell layer and were designated as displaced amacrine cells. Each type of SP-like immunoreactive cell was observed in the central and peripheral retina. SP-immunopositive processes were observed in the inner plexiform layer as a sparse plexus in sublamina 1 and as a denser network of fibers in sublamina 5. Seventy-eight percent of the 110 somatostatin-immunopositive cells observed were designated as Type 1 amacrine cells. Another 12% of SOM-cells were classified as displaced amacrine cells, while only two SOM-immunopositive Type 2 amacrine cells were observed. Nine percent of the SOM-cells were designated as interplexiform cells, based on their giving rise to processes distributing in the outer plexiform layer as well as processes ramifying in the inner plexiform layer. Each type of SOM-immunoreactive cell was observed in the central and peripheral retina, with the exception of the Type 2 amacrine cells, whose somas were only found in the central retina. Lastly, SOM-immunopositive processes in the inner plexiform layer appeared as a fine plexus in sublamina 1 and as a somewhat denser network of fibers in sublamina 5.     

肠鸣音的建模与模拟研究

本文对肠道运动进行分析，从结构上研究肠鸣音的产生机理和肠鸣音的时域、频域特点，从而得到其物理模型，并用等效电路来模拟肠鸣音的产生，为研究肠鸣音的数学模型，以及临床医学研究提供了方便。     

脑血流断层显像Bullseye显示

为了探讨用Bullseye显示脑血流灌注显像数据的可能性,对8例典型脑梗塞病例及15例脑血流断层显像常规分析可疑病例的脑血流断层显像的横断面数据进行Bullscye显示,结果8例典型病人病灶用普通Bullseye即显示良好;常规分析可疑病例病变用普通Bullseye 8例显示良好,变黑Bullseye 13例显示出病灶;结果提示利用Bullseye显示脑血流灌注显像数据的可能。     

Protection from pathogenic SIV challenge using multigenic DNA vaccines

To assess DNA immunization as a strategy for protecting against HIV infection in humans, we utilized SIVmne infection of Macaca fascicularis as a vaccine challenge model with moderate pathogenic potential. We compared the efficacy of DNA immunization alone and in combination with subunit protein boosts. All of the structural and regulatory genes of SIVmne clone 8 were cloned into mammalian expression vectors under the control of the CMV IE-1 promoter. Eight M. fascicularis were immunized twice with 3 mg of plasmid DNA divided between two sites; intramuscular and intradermal. Four primed macaques received a further two DNA immunizations at weeks 16-36, while the second group of four were boosted with 250 microg recombinant gp160 plus 250 microg recombinant Gag-Pol particles formulated in MF-59 adjuvant. Half of the controls received four immunizations of vector DNA; half received two vector DNA and two adjuvant immunizations. As expected, humoral immune responses were stronger in the macaques receiving subunit boosts, but responses were sustained in both groups. Significant neutralizing antibody titers to SIVmne were detected in one of the subunit-boosted animals and in none of the DNA-only animals prior to challenge. T-cell proliferative responses to gp160 and to Gag were detected in all immunized animals after three immunizations, and these responses increased after four immunizations. Cytokine profiles in PHA-stimulated PBMC taken on the day of challenge showed trends toward Thl responses in 2/4 macaques in the DNA vaccinated group and in 1/4 of the DNA plus subunit vaccinated macaques; Th2 responses in 3/4 DNA plus subunit-immunized macaques; and Th0 responses in 4/4 controls. In bulk CTL culture, SIV specific lysis was low or undetectable, even after four immunizations. However, stable SIV Gag-Pol- and env-specific T-cell clones (CD3+ CD8+) were isolated after only two DNA immunizations, and Gag-Pol- and Nef-specific CTL lines were isolated on the day of challenge. All animals were challenged at week 38 with SIVmne uncloned stock by the intrarectal route. Based on antibody anamnestic responses (western, ELISA, and neutralizing antibodies) and virus detection methods (co-culture of PBMC and LNMC, nested set PCR- of DNA from PBMC and LNMC, and plasma QC-PCR), there were major differences between the groups in the challenge outcome. Surprisingly, sustained low virus loads were observed only in the DNA group, suggesting that four immunizations with DNA only elicited more effective immune responses than two DNA primes combined with two protein boosts. Multigenic DNA vaccines such as these, bearing all structural and regulatory genes, show significant promise and may be a safe alternative to live-attenuated vaccines.     

Proposed methods for the measurement of regional renal blood flow using heat transfer analysis

The kidney, with its heterogeneous regional perfusion in the two anatomically and functionally distinct vascular beds of the renal cortex and medulla, and with its nonuniform blood vessel geometries, presents a unique challenge for measuring intrarenal blood flow distribution. Determining whole organ perfusion, on the other hand, is comparatively simple for the kidney, but it provides relatively little information about the suspected dependency of renal excretory function on local perfusion rate. Among the variety of methods proposed for gauging regional renal blood flow, some depend on measuring one or more of the tissue's thermal properties. The most straightforward, but least reliable, involve measurements either of focal tissue temperature alone, or of regional tissue thermal gradients. Simply using heat as a diffusible indicator, however, is unreliable as a measure of blood flow, for many of the same reasons that using an inert gas in a dilution technique is unreliable. Recently developed thermal analytical methods, though, hold promise for measuring local tissue blood flow with accuracy and precision. Two of them are reviewed here. One depends on measurement of the effective thermal conductivity of a small mass of tissue by evaluating the steady state ratio between regional unidirectional heat flux across it and the associated temperature gradient in one vector along a segment of it through an imposed spheroidal heat field. The other depends on analyses of tissue temperature decay subsequent to a controlled pulse of heat delivered through a small inserted thermistor bead. Both techniques use bioheat transfer equations to deduce regional blood flow Research by K.R. Holmes and M.M. Chen was supproted by NIH-NHLBI Grant HL27011, that by T. Adams and S.R. Heisey through the Michigan Heart Association, and that by W.S. Spielman through a grant from the NSF (PCM 8110588) who is a recipient of NIH Research Career Development Award HL01010.     

Attachment, proliferation and differentiation of osteoblasts on random biopolyester poly(3-hydroxybutyrate-co-3-hydroxyhexanoate) scaffolds

Rabbit bone marrow cells were inoculated on 3D scaffolds of poly(lactic acid) (PLA), poly(3-hydroxybutyrate) (PHB) and poly(3-hydroxybutyrate-co-3-hydroxyhexanoate) (PHBHHx) to evaluate their in vitro biocompatibilities. It was found that PHBHHx had the best performance on attachment, proliferation of bone marrow cells. The cells on PHBHHx scaffolds presented typical osteoblast phenotypes: round cell shape, high alkaline phosphotase (ALP) activity, strong calcium deposition, and fibrillar collagen synthesis. After incubation for 10 days, cells grown on PHBHHx scaffolds were approximately 2x10(5)ml(-1), 40% more than that on PHB scaffolds and 60% more than that on PLA scaffolds. ALP activity of the cells grown on PHBHHx scaffolds was up to about 65U/g scaffolds, 50% higher than that of PHB and PLA, respectively. The scanning electronic microscopy (SEM) results showed that PHBHHx scaffolds had the appropriate roughness for osteoblast attachment and proliferation comparing with PHB and PLA. All these indicated that PHBHHx was a suitable biomaterial for osteoblast attachment, proliferation and differentiation from bone marrow cells.     

Technical quality evaluation of EEG recording based on electroencephalographers' knowledge

The aim of this study is to develop a technical quality evaluation system of electroencephalogram (EEG) recording in order to acquire technically satisfactory EEG records, which may contribute to the accuracy improvement of EEG interpretation. In our developed system, the evaluation of EEG recording comprises the detection of technical artifacts and physiological status, which indicates the recording status objectively. In addition, the caution signals to users are generated in the system according to the undesired status detected. The information displayed to users includes the updated EEG records and instant evaluation results. Two examples of evaluation results are introduced in this paper, illustrating unsatisfactory records and artifact free records, respectively. The experimental results are proposed to verify the effectiveness of the technical quality evaluation of EEG recording. The implementation of the technical quality evaluation of EEG recording is helpful to acquire technically satisfactory EEG records, which may improve the accuracy of results in both the visual and the automatic EEG interpretation, and ease the laborious work of EEG technicians in the recording progress.     

Meta-analysis of gross insertions causing human genetic disease: novel mutational mechanisms and the role of replication slippage

Although gross insertions (>20 bp) comprise <1% of disease-causing mutations, they nevertheless represent an important category of pathological lesion. In an attempt to study these insertions in a systematic way, 158 gross insertions ranging in size between 21 bp and approximately 10 kb were identified using the Human Gene Mutation Database (www.hgmd.org). A careful meta-analytical study revealed extensive diversity in terms of the nature of the inserted DNA sequence and has provided new insights into the underlying mutational mechanisms. Some 70% of gross insertions were found to represent sequence duplications of different types (tandem, partial tandem, or complex). Although most of the tandem duplications were explicable by simple replication slippage, the three complex duplications appear to result from multiple slippage events. Some 11% of gross insertions were attributable to nonpolyglutamine repeat expansions (including octapeptide repeat expansions in the prion protein gene [PRNP] and polyalanine tract expansions) and evidence is presented to support the contention that these mutations are also caused by replication slippage rather than by unequal crossing over. Some 17% of gross insertions, all >or=276 bp in length, were found to be due to LINE-1 (L1) retrotransposition involving different types of element (L1 trans-driven Alu, L1 direct, and L1 trans-driven SVA). A second example of pathological mitochondrial-nuclear sequence transfer was identified in the USH1C gene but appears to arise via a novel mechanism, trans-replication slippage. Finally, evidence for another novel mechanism of human genetic disease, involving the possible capture of DNA oligonucleotides, is presented in the context of a 26-bp insertion into the ERCC6 gene.