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1.
2.
Nicotine and cannabinoids as adjuncts to neuroleptics in the treatment of Tourette syndrome and other motor disorders 总被引:2,自引:0,他引:2
D E Moss P Z Manderscheid S P Montgomery A B Norman P R Sanberg 《Life sciences》1989,44(21):1521-1525
Animal studies suggest nicotine and cannabinoids may significantly enhance the therapeutic value of neuroleptics in motor disorders. This was recently demonstrated in humans by the finding that chewing nicotine gum produced striking relief from tics and other symptoms of Tourette syndrome not controlled by neuroleptic treatment alone. It appears that the use of nicotine or cannabinoids may greatly improve the clinical response to neuroleptics in motor disorders. 相似文献
3.
The fusarium mycotoxin zearalenone was transformed in cell suspension cultures of Zea mays giving α- and β-zearalenol and the β-D-glu cos ides of zearalenone and α- and β-zearalenol. The structure of zearalenone-4-β-D-glucopyranoside was determined by liquid — chromatography-mass spectrometry and specific hydrolysis with β-glucosidase. α- and β-zearalenol and their glucosides were identified by co chromatography using tic and HPLC and glucosidase — treatment Up to 50% of the mycotoxin added was bound to a non extractable or “bound” residue fraction. After treating this residue by a sequential cell wall fractionation procedure, zearalenone was found to be bound mainly to starch, hemicellulose, and lignin fractions. 相似文献
4.
Gene transfer is a major factor in bacterial evolution 总被引:17,自引:3,他引:14
Lateral gene transfer in four strains of Salmonella enterica has been
assessed using genomic subtraction. Strain LT2 (subspecies I serovar
Typhimurium) chromosomal DNA was used as target and subtracted by three
subspecies I strains of serovars Typhimurium (S21), Muenchen (S71), Typhi
(M229), and a subspecies V strain (M321). Data from probing random cosmids
of LT2 DNA with preparations of the residual LT2 DNA after subtraction were
used to estimate the amounts of LT2 DNA not able to hybridize to strains
S21, S71, M229, and M321 to be in the range of 84-106, 191-355, 305-629,
and 778-1,286 kb, respectively. Several lines of evidence indicate that
most of this DNA is from genes not present in strain M321 and not from
genes that have diverged in sequence. The amounts correlate with the
divergence of the four strains as revealed by multilocus enzyme
electrophoresis and sequence variation of housekeeping genes. Sequence of
39 of the fragments from the M321 subtracted residual LT2 DNA revealed only
six inserts of known gene function with evidence of both gain and loss of
genes during the development of S. enterica clones. Sixteen of the 39
segments have 45% or lower G+C content, below the species average, but over
half are within the normal range for the species. We conclude that even
within a species, clones may differ by up to 20% of chromosomal DNA,
indicating a major role for lateral transfer, and that on the basis of G+C
content, a significant proportion of the DNA is from distantly related
species.
相似文献
5.
PR Marcelino MS Aoki AFS Arruda CG Freitas A Mendez-Villanueva A Moreira 《Biology of sport / Institute of Sport》2016,33(1):37-42
The purpose of this study was to investigate the effect of court size on physiological responses and physical performance of young elite basketball players. Twelve male basketball players (18.6 ± 0.5 years; 88.8 ± 14.5 kg; 192.6 ± 6.5 cm) from an under-19 team performed two small-sided games (matches) with different court areas (28x15 m and 28x9 m; 28x15 and 28x9 protocols). The number of players (3x3) was kept the same in each protocol. The players performed a repeated-sprint ability (RSA) test before and after each match. Blood lactate concentration was collected before (pre) and after (post) the matches, and the session rating of perceived exertion (session-RPE) was determined 30 minutes after the match. Best and mean time in the RSA test were not different between the 28x15 and the 28x9 match protocols (p > 0.05). A significant difference was observed for lactate concentration from pre- to post-match (p < 0.05) in both protocols (28x15 and 28x9); however, there was no significant interaction between protocols. A similar session-RPE mean score (28x15: 7.2 ± 1.4 and 28x9: 6.6 ± 1.4) was detected for both protocols (p > 0.05, ES=0.41). In summary, the results of the current study suggest that the different court areas induced similar responses. Although there was no significant difference in effort perception, players tended to perceive a greater effort in the larger court size. 相似文献
6.
Evidence of compromised blood-spinal cord barrier in early and late symptomatic SOD1 mice modeling ALS 总被引:1,自引:0,他引:1
Garbuzova-Davis S Saporta S Haller E Kolomey I Bennett SP Potter H Sanberg PR 《PloS one》2007,2(11):e1205
Background
The blood-brain barrier (BBB), blood-spinal cord barrier (BSCB), and blood-cerebrospinal fluid barrier (BCSFB) control cerebral/spinal cord homeostasis by selective transport of molecules and cells from the systemic compartment. In the spinal cord and brain of both ALS patients and animal models, infiltration of T-cell lymphocytes, monocyte-derived macrophages and dendritic cells, and IgG deposits have been observed that may have a critical role in motor neuron damage. Additionally, increased levels of albumin and IgG have been found in the cerebrospinal fluid in ALS patients. These findings suggest altered barrier permeability in ALS. Recently, we showed disruption of the BBB and BSCB in areas of motor neuron degeneration in the brain and spinal cord in G93A SOD1 mice modeling ALS at both early and late stages of disease using electron microscopy. Examination of capillary ultrastructure revealed endothelial cell degeneration, which, along with astrocyte alteration, compromised the BBB and BSCB. However, the effect of these alterations upon barrier function in ALS is still unclear. The aim of this study was to determine the functional competence of the BSCB in G93A mice at different stages of disease.Methodology/Principal Findings
Evans Blue (EB) dye was intravenously injected into ALS mice at early or late stage disease. Vascular leakage and the condition of basement membranes, endothelial cells, and astrocytes were investigated in cervical and lumbar spinal cords using immunohistochemistry. Results showed EB leakage in spinal cord microvessels from all G93A mice, indicating dysfunction in endothelia and basement membranes and confirming our previous ultrastructural findings on BSCB disruption. Additionally, downregulation of Glut-1 and CD146 expressions in the endothelial cells of the BSCB were found which may relate to vascular leakage.Conclusions/Significance
Results suggest that the BSCB is compromised in areas of motor neuron degeneration in ALS mice at both early and late stages of the disease. 相似文献7.
8.
Paul R. Sanberg Dong‐Hyuk Park Nicole Kuzmin‐Nichols Eduardo Cruz Nelson Americo Hossne Jr Enio Buffolo Alison E. Willing 《Journal of cellular and molecular medicine》2010,14(3):553-563
Neovascularization is an integral process of inflammatory reactions and subsequent repair cascades in tissue injury. Monocytes/macrophages play a key role in the inflammatory process including angiogenesis as well as the defence mechanisms by exerting microbicidal and immunomodulatory activity. Current studies have demonstrated that recruited monocytes/macrophages aid in regulating angiogenesis in ischemic tissue, tumours and chronic inflammation. In terms of neovascularization followed by tissue regeneration, monocytes/macrophages should be highly attractive for cell-based therapy compared to any other stem cells due to their considerable advantages: non-oncogenic, non-teratogenic, multiple secretary functions including pro-angiogenic and growth factors, straightforward cell harvesting procedure and non-existent ethical controversy. In addition to adult origins such as bone marrow or peripheral blood, umbilical cord blood (UCB) can be a potential source for autologous or allogeneic monocytes/macrophages. Especially, UCB monocytes should be considered as the first candidate owing to their feasibility, low immune rejection and multiple characteristic advantages such as their anti-inflammatory properties by virtue of their unique immune and inflammatory immaturity, and their pro-angiogenic ability. In this review, we present general characteristics and potential of monocytes/macrophages for cell-based therapy, especially focusing on neovascularization and UCB-derived monocytes. 相似文献
9.
Francine Z Marques Simon PR Romaine Matthew Denniff James Eales John Dormer Ingrid M Garrelds Lukasz Wojnar Katarzyna Musialik Barbara Duda-Raszewska Bartlomiej Kiszka Magdalena Duda Brian J Morris Nilesh J Samani AH Jan Danser Pawel Bogdanski Ewa Zukowska-Szczechowska Fadi J Charchar Maciej Tomaszewski 《Molecular medicine (Cambridge, Mass.)》2015,21(1):739-748
MicroRNA-181a binds to the 3′ untranslated region of messenger RNA (mRNA) for renin, a rate-limiting enzyme of the renin-angiotensin system. Our objective was to determine whether this molecular interaction translates into a clinically meaningful effect on blood pressure and whether circulating miR-181a is a measurable proxy of blood pressure. In 200 human kidneys from the TRANScriptome of renaL humAn TissuE (TRANSLATE) study, renal miR-181a was the sole negative predictor of renin mRNA and a strong correlate of circulating miR-181a. Elevated miR-181a levels correlated positively with systolic and diastolic blood pressure in TRANSLATE, and this association was independent of circulating renin. The association between serum miR-181a and systolic blood pressure was replicated in 199 subjects from the Genetic Regulation of Arterial Pressure of Humans In the Community (GRAPHIC) study. Renal immunohistochemistry and in situ hybridization showed that colocalization of miR-181a and renin was most prominent in collecting ducts where renin is not released into the systemic circulation. Analysis of 69 human kidneys characterized by RNA sequencing revealed that miR-181a was associated with downregulation of four mitochondrial pathways and upregulation of 41 signaling cascades of adaptive immunity and inflammation. We conclude that renal miR-181a has pleiotropic effects on pathways relevant to blood pressure regulation and that circulating levels of miR-181a are both a measurable proxy of renal miR-181a expression and a novel biochemical correlate of blood pressure. 相似文献
10.
Kouki?HikosakaEmail author Yusuke?Onoda Toshihiko?Kinugasa Hisae?Nagashima Niels?PR?Anten Tadaki?Hirose 《Ecological Research》2005,20(3):243-253
Elevated CO2 enhances photosynthesis and growth of plants, but the enhancement is strongly influenced by the availability of nitrogen. In this article, we summarise our studies on plant responses to elevated CO2. The photosynthetic capacity of leaves depends not only on leaf nitrogen content but also on nitrogen partitioning within a leaf. In Polygonum cuspidatum, nitrogen partitioning among the photosynthetic components was not influenced by elevated CO2 but changed between seasons. Since the alteration in nitrogen partitioning resulted in different CO2-dependence of photosynthetic rates, enhancement of photosynthesis by elevated CO2 was greater in autumn than in summer. Leaf mass per unit area (LMA) increases in plants grown at elevated CO2. This increase was considered to have resulted from the accumulation of carbohydrates not used for plant growth. With a sensitive analysis of a growth model, however, we suggested that the increase in LMA is advantageous for growth at elevated CO2 by compensating for the reduction in leaf nitrogen concentration per unit mass. Enhancement of reproductive yield by elevated CO2 is often smaller than that expected from vegetative growth. In Xanthium canadense, elevated CO2 did not increase seed production, though the vegetative growth increased by 53%. As nitrogen concentration of seeds remained constant at different CO2 levels, we suggest that the availability of nitrogen limited seed production at elevated CO2 levels. We found that leaf area development of plant canopy was strongly constrained by the availability of nitrogen rather than by CO2. In a rice field cultivated at free-air CO2 enrichment, the leaf area index (LAI) increased with an increase in nitrogen availability but did not change with CO2 elevation. We determined optimal LAI to maximise canopy photosynthesis and demonstrated that enhancement of canopy photosynthesis by elevated CO2 was larger at high than at low nitrogen availability. We also studied competitive asymmetry among individuals in an even-aged, monospecific stand at elevated CO2. Light acquisition (acquired light per unit aboveground mass) and utilisation (photosynthesis per unit acquired light) were calculated for each individual in the stand. Elevated CO2 enhanced photosynthesis and growth of tall dominants, which reduced the light availability for shorter subordinates and consequently increased size inequality in the stand. 相似文献