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81.
Laterality is a basic characteristic of the brain which is detectable early in life. Although early experiences affect laterality of the mature brain, there are no reports on their immediate neurochemical effects during neonatal life, which could provide evidence as to the mechanisms leading to the lateralized brain. In order to address this issue, we determined the differential protein expression profile of the left and right hippocampus of 13-day-old rat control (CTR) pups, as well as following exposure to an early experience involving either receipt (RER) or denial (DER) of the expected reward of maternal contact. Proteomic analysis was performed by 2-dimensional polyacrylamide gel electrophoresis (PAGE) followed by mass spectroscopy. The majority of proteins found to be differentially expressed either between the three experimental groups (DER, RER, CTR) or between the left and right hemisphere were cytoskeletal (34%), enzymes of energy metabolism (32%), and heat shock proteins (17%). In all three groups more proteins were up-regulated in the left compared to the right hippocampus. Tubulins were found to be most often up-regulated, always in the left hippocampus. The differential expression of β-tubulin, β-actin, dihydropyrimidinase like protein 1, glial fibrillary acidic protein (GFAP) and Heat Shock protein 70 revealed by the proteomic analysis was in general confirmed by Western blots. Exposure to the early experience affected brain asymmetry: In the RER pups the ratio of proteins up-regulated in the left hippocampus to those in the right was 1.8, while the respective ratio was 3.6 in the CTR and 3.4 in the DER. Our results could contribute to the elucidation of the cellular mechanisms mediating the effects of early experiences on the vulnerability for psychopathology, since proteins shown in our study to be differentially expressed (e.g. tubulins, dihydropyrimidinase like proteins, 14-3-3 protein, GFAP, ATP synthase, α-internexin) have also been identified in proteomic analyses of post-mortem brains from psychiatric patients.  相似文献   
82.
The frequent occurrence of stereotyped heavy complementarity-determining region 3 (VH CDR3) sequences among unrelated cases with chronic lymphocytic leukemia (CLL) is widely taken as evidence for antigen selection. Stereotyped VH CDR3 sequences are often defined by the selective association of certain immunoglobulin heavy diversity (IGHD) genes in specific reading frames with certain immunoglobulin heavy joining (IGHJ ) genes. To gain insight into the mechanisms underlying VH CDR3 restrictions and also determine the developmental stage when restrictions in VH CDR3 are imposed, we analyzed partial IGHD-IGHJ rearrangements (D-J) in 829 CLL cases and compared the productively rearranged D-J joints (that is, in-frame junctions without junctional stop codons) to (a) the productive immunoglobulin heavy variable (IGHV )-IGHD-IGHJ rearrangements (V-D-J) from the same cases and (b) 174 D-J rearrangements from 160 precursor B-cell acute lymphoblastic leukemia cases (pre-B acute lymphoblastic leukemia [ALL]). Partial D-J rearrangements were detected in 272/829 CLL cases (32.8%). Sequence analysis was feasible in 238 of 272 D-J rearrangements; 198 of 238 (83.2%) were productively rearranged. The D-J joints in CLL did not differ significantly from those in pre-B ALL, except for higher frequency of the IGHD7-27 and IGHJ6 genes in the latter. Among CLL carrying productively rearranged D-J, comparison of the IGHD gene repertoire in productive V-D-J versus D-J revealed the following: (a) overuse of IGHD reading frames encoding hydrophilic peptides among V-D-J and (b) selection of the IGHD3-3 and IGHD6-19 genes in V-D-J junctions. These results document that the IGHD and IGHJ gene biases in the CLL expressed VH CDR3 repertoire are not stochastic but are directed by selection operating at the immunoglobulin protein level.  相似文献   
83.
Background:Non-alcoholic fatty liver disease (NAFLD) constitutes a global pandemic. An intricate network among cytokines and lipids possesses a central role in NAFLD pathogenesis. Red blood cells comprise an important source of both cytokines and signaling lipids and have an important role in molecular crosstalk during immunometabolic deregulation. However, their role in NAFLD has not been thoroughly investigated.Methods:Conditioned media from erythrocytes derived from 10 NAFLD patients (4 men, 6 women, aged 57.875±15.16) and 10 healthy controls (4 men, 6 women, aged 39.3±15.55) was analyzed for the cytokines IFN-γ, TNF-α, CCL2, CCL5, IL-8, IL-1β, IL-12p40, IL-17, MIP-1β, the signaling lipids sphingosine-1-phosphate (S1P) and lysophosphatidic acid (LPA), and cholesterol. Their effect on the cytokine profile released by RAW 264.7 macrophages was also studied.Results:MCP1 levels were greater in conditioned growth medium from NAFLD patient erythrocytes than in that from healthy controls (37±40 vs 6.51±5.63 pg/ml). No statistically significant differences were found between patients and healthy controls with regard to S1P, LPA, cholesterol, or eight other cytokines. TNF-a release by RAW 264.7 cells was greater after incubation with patient-derived erythrocyte-conditioned medium than in medium without RAW 264.7 cells from either healthy or NAFLD subjects.Conclusion:Erythrocytes may contribute to liver infiltration by monocytes, and macrophage activation, partially due to CCL2 release, in the context of NAFLD..Key Words: Cytokines, Erythrocytes, Lipids, Non-alcoholic fatty liver disease, Signaling  相似文献   
84.
Monounsaturated fatty acids (MUFA) are emerging health biomarkers, and in particular the ratio between palmitoleic acid (9cis-16:1) and palmitic acid (16:0) affords the delta-9 desaturase index that is increased in obesity. Recently, other positional and geometrical MUFA isomers belonging to the hexadecenoic family (C16 MUFA) were found in circulating lipids, such as sapienic acid (6cis-16:1), palmitelaidic acid (9trans-16:1) and 6trans-16:1. In this work we report: i) the identification of sapienic acid as component of human erythrocyte membrane phospholipids with significant increase in morbidly obese patients (n = 50) compared with age-matched lean controls (n = 50); and ii) the first comparison of erythrocyte membrane phospholipids (PL) and plasma cholesteryl esters (CE) in morbidly obese patients highlighting that some of their fatty acid levels have opposite trends: increases of both palmitic and sapienic acids with the decrease of linoleic acid (9cis,12cis-18:2, omega-6) in red blood cell (RBC) membrane PL were reversed in plasma CE, whereas the increase of palmitoleic acid was similar in both lipid species. Consequentially, desaturase enzymatic indexes gave different results, depending on the lipid class used for the fatty acid content. The fatty acid profile of morbidly obese subjects also showed significant increases of stearic acid (C18:0) and C20 omega-6, as well as decreases of oleic acid (9cis-18:1) and docosahexaenoic acid (C22:6 omega-3) as compared with lean healthy controls. Trans monounsaturated and polyunsaturated fatty acids were also measured and found significantly increased in both lipid classes of morbidly obese subjects. These results highlight the C16 MUFA isomers as emerging metabolic marker provided that the assignment of the double bond position and geometry is correctly performed, thus identifying the corresponding lipidomic pathway. Since RBC membrane PL and plasma CE have different fatty acid trends, caution must also be used in the choice of lipid species for the interpretation of lipidomic profiles.  相似文献   
85.
Transformation and transduction crosses involving recA1, recB2, and urv-1 mutations have shown that these mutations belong to three distinct unlinked genetic loci. The precise position of these loci on the Bacillus subtilis chromosome map has been determined. The behavior of recB2 strains in transformation studies suggested a dominance of recB2(+) function over recB2 and an early expression of this phenotype during transformation. Strains bearing two ultraviolet sensitivity markers possess a phenotype characteristic of the marker with the most adverse effect on recombination. The possibility that the effects of the two mutations are additive was also considered. Results are also presented which show that a phage-induced enzyme is not responsible for the high transducibility of recA1 strains.  相似文献   
86.
A method was developed for the statistical analysis of growth data from synchronized growth experiments. The analysis provided a firm basis for the recognition of synchrony and the objective graphical presentation of the growth pattern of a synchronized culture. The latter could then supply reliably the parameters required for the calculation of a synchronization index, i.e. for the synchrony evaluation.  相似文献   
87.
88.
Transformation experiments with Bacillus subtilis strains carrying trpE26 (the marker responsible for the detection of merodiploid clones after transformation or transduction) have established the precise position of this marker on the "aromatic region" of the chromosome, at the distal end of the anthranilate synthetase locus. Integration efficiency of the mutant allele (trpE26) seems to be very low. Co-transfer of markers situated on either side of it is almost nil when both donor and recipient carry this mutation. The "exclusion" of trpE26 does not, however, affect recombination frequencies for nearby markers. To explain these facts we considered the hypothesis of a preferential breakage of the deoxyribonucleic acid (DNA) at the trpE26 site or that of an insertion mutation. These studies have also demonstrated the establishment of physical linkage of a marker from the exogenote (hisH2) to a resident marker (tyrA1) in stable and unstable merodiploid clones, thus confirming integration of the donor DNA segment into a genetic structure of the recipient. Furthermore, duplication was shown in merodiploid clones (through reversion and transformation) for a locus of the recipient (tyrA) which was not involved in the initial transformation. This suggests that the diploid condition in this region extends beyond the transformed area. Interpretation of the genetic constitution of these partial diploids calls for postulation of the existence of long duplications, a second (incomplete) chromosome, or an episome-like element.  相似文献   
89.
Two cases are reported that involve heterotopic bone formation in midline sternotomy scars. The authors relate similar complications associated with abdominal incisions and discuss possible causes.  相似文献   
90.
Recent technologic advances make it possible to measure reliably serum or plasma ionized calcium with a high degree of accuracy. In this study, with the use of 16 mongrel dogs, the quantitation of the hemodynamic response to acute changes in ionized calcium was attempted. It was found that normal cardiac function required a normal level of ionized calcium. In intact animals, severe depression of myocardium is masked by pressor reflexes designed to maintain homeostasis. In their absence, myocardial depression is readily apparent. Animals that are hypercalcemic at the beginning of infusion respond in essentially the same manner. To a degree previously unsuspected, myocardial function depends upon a constant level of ionized calcium.  相似文献   
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