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1.
Abstract: The mRNA encoding μ-opioid receptors is expressed in neurons of the globus pallidus, a region of the basal ganglia that receives a dense enkephalinergic innervation from the striatum. The regulation of the mRNAs encoding the opioid peptide enkephalin in the striatum and the μ-opioid receptor in the globus pallidus was examined with in situ hybridization histochemistry following short- or long-term haloperidol treatments, which alter striatal enkephalin mRNA levels. Animals were administered haloperidol daily for 3 or 7 days (1 mg/kg, s.c.) or continuously for 8 months (1 mg/kg, depot followed by oral). Enkephalin and μ-opioid receptor mRNA levels were unchanged after 3 days of haloperidol treatment. In contrast, the enkephalin mRNA level was increased in the striatum, and μ-opioid receptor mRNA levels were markedly decreased in the globus pallidus after 7 days of haloperidol administration. Similar effects were observed in rats treated with haloperidol for 8 months. The results provide the first evidence of regulation of μ-opioid receptor mRNA in vivo.  相似文献   
2.
In previous experiments rats pretreated with slow-release d-amphetamine (d-Amp) pellets for 412 days, given a 12-hr drug-free period, and then injected with d-Amp have been found to show a behavioral syndrome which has similarities to that induced by acute injections of the hallucinogens LSD and mescaline. The present results indicate that rats administered this same drug regimen have large decreases in Dopamine (DA), dihydroxyphenyl acetic acid (Dopac), and homovanillic acid (HVA) in caudate nucleus, smaller decreases in DA with no changes in Dopac and HVA levels in nucleus accumbens, but no alterations in 5-hydroxytryptamine (5HT) and 5-hydroxyindole acetic acid (5HIAA) levels in caudate, accumbens, brainstem and hippocampus. Increased 5HIAA levels are found in rats sacrificed with pellets intact following 3 days of continuous d-Amp administration, while sleep deprived and in motor stereotypies. The late and hallucinatory stage following continuous d-amp is correlated more closely with alterations in dopamine than of 5HT.  相似文献   
3.
We have isolated as recombinant DNA clones, in the plasmid pBR322, regions of the herpesvirus type 1 genome spanning the region between 0.53 and 0.6 on the prototypical arrangement. This 11,000-base-pair region corresponds to 10% of the large unique region and encodes five major and several minor mRNA species abundant at different times after infection, which range in length from 7 to 1 kilobase. In this report, we have used RNA transfer blots and S1 nuclease digestion of hybrids between viral DNA and polyribosomal RNA to precisely localize (+/- 0.1 kilobase) these mRNA's. Comparison of neutral and alkaline gels of S1 nuclease-digested hybrids indicates no internal introns in the coding sequences of these mRNA's, although noncontiguous leader sequences near (ca. 0.1 kilobase) the 5' ends of any or all mRNA's could not be excluded. The 5' ends of several late mRNA's that are encoded opposite DNA strands map very close to one another, and the 3' ends of a major late and a major early mRNA, which are partially colinear, terminate in the same region. In vitro translation of the viral mRNA's isolated by hybridization with DNA bound to cellulose and fractionation of mRNA species on denaturing agarose gels allowed us to assign specific polypeptide products to each of the mRNA's characterized. Among other results, it was demonstrated unequivocally that two major late mRNA's, which partially overlap, encode the same polypeptide.  相似文献   
4.
Global climatic changes may lead to the arrival of multiple range‐expanding species from different trophic levels into new habitats, either simultaneously or in quick succession, potentially causing the introduction of manifold novel interactions into native food webs. Unraveling the complex biotic interactions between native and range‐expanding species is critical to understand the impact of climate change on community ecology, but experimental evidence is lacking. In a series of laboratory experiments that simulated direct and indirect species interactions, we investigated the effects of the concurrent arrival of a range‐expanding insect herbivore in Europe, Spodoptera littoralis, and its associated parasitoid Microplitis rufiventris, on the native herbivore Mamestra brassicae, and its associated parasitoid Microplitis mediator, when co‐occurring on a native plant, Brassica rapa. Overall, direct interactions between the herbivores were beneficial for the exotic herbivore (higher pupal weight than the native herbivore), and negative for the native herbivore (higher mortality than the exotic herbivore). At the third trophic level, both parasitoids were unable to parasitize the herbivore they did not coexist with, but the presence of the exotic parasitoid still negatively affected the native herbivore (increased mortality) and the native parasitoid (decreased parasitism rate), through failed parasitism attempts and interference effects. Our results suggest different interaction scenarios depending on whether S. littoralis and its parasitoid arrive to the native tritrophic system separately or concurrently, as the negative effects associated with the presence of the parasitoid were dependent on the presence of the exotic herbivore. These findings illustrate the complexity and interconnectedness of multitrophic changes resulting from concurrent species arrival to new environments, and the need for integrating the ecological effects of such arrivals into the general theoretical framework of global invasion patterns driven by climatic change.  相似文献   
5.

Background

Systemic inflammation may contribute to cachexia in patients with chronic obstructive pulmonary disease (COPD). In this longitudinal study we assessed the association between circulating C-reactive protein (CRP), tumor necrosis factor (TNF)-α, interleukin (IL)-1ß, and IL-6 levels and subsequent loss of fat free mass and fat mass in more than 400 COPD patients over three years.

Methods

The patients, aged 40–76, GOLD stage II-IV, were enrolled in 2006/07, and followed annually. Fat free mass and fat mass indexes (FFMI & FMI) were calculated using bioelectrical impedance, and CRP, TNF-α, IL-1ß, and IL-6 were measured using enzyme immunoassays. Associations with mean change in FFMI and FMI of the four inflammatory plasma markers, sex, age, smoking, FEV1, inhaled steroids, arterial hypoxemia, and Charlson comorbidity score were analyzed with linear mixed models.

Results

At baseline, only CRP was significantly (but weakly) associated with FFMI (r = 0.18, p < 0.01) and FMI (r = 0.27, p < 0.01). Univariately, higher age, lower FEV1, and use of beta2-agonists were the only significant predictors of decline in FFMI, whereas smoking, hypoxemia, Charlson score, and use of inhaled steroids predicted increased loss in FMI. Multivariately, high levels of TNF-α (but not CRP, IL-1ß or IL-6) significantly predicted loss of FFMI, however only in patients with established cachexia at entry.

Conclusion

This study does not support the hypothesis that systemic inflammation is the cause of accelerated loss of fat free mass in COPD patients, but suggests a role for TNF-α in already cachectic COPD patients.  相似文献   
6.
The objective of this study was to determine whether cells in G(0) phase are functionally distinct from those in G(1) with regard to their ability to respond to the inducers of DNA synthesis and to retard the cell cycle traverse of the G(2) component after fusion. Synchronized populations of HeLa cells in G(1) and human diploid fibroblasts in G(1) and G(0) phases were separately fused using UV-inactivated Sendai virus with HeLa cells prelabeled with [(3)H]ThdR and synchronized in S or G(2) phases. The kinetics of initiation of DNA synthesis in the nuclei of G(0) and G(1) cells residing in G(0)/S and G(1)/S dikaryons, respectively, were studied as a function of time after fusion. In the G(0)/G(2) and G(1)/G(2) fusions, the rate of entry into mitosis of the heterophasic binucleate cells was monitored in the presence of Colcemid. The effects of protein synthesis inhibition in the G(1) cells, and the UV irradiation of G(0) cells before fusion, on the rate of entry of the G(2) component into mitosis were also studied. The results of this study indicate that DNA synthesis can be induced in G(0)nuclei after fusion between G(0)- and S-phase cells, but G(0) nuclei are much slower than G(1) nuclei in responding to the inducers of DNA synthesis because the chromatin of G(0) cells is more condensed than it is in G(1) cells. A more interesting observation resulting from this study is that G(0) cells is more condensed than it is in G(1) cells. A more interesting observation resulting from this study is that G(0) cells differ from G(1) cells with regard to their effects on the cell cycle progression of the G(2) nucleus into mitosis. This difference between G(0) and G(1) cells appears to depend on certain factors, probably nonhistone proteins, present in G(1) cells but absent in G(0) cells. These factors can be induced in G(0) cells by UV irradiation and inhibited in G(1) cells by cycloheximide treatment.  相似文献   
7.
Determination of temperature requirements for many economically important insects is a cornerstone of pest management. For bark beetles (Coleoptera: Curculionidae, Scolytinae), this information can facilitate timing of management strategies. Our goals were to determine temperature predictors for flight initiation of three species of Ips bark beetles, five species of Dendroctonus bark beetles, and two genera of bark beetle predators, Enoclerus spp. (Coleoptera: Cleridae) and Temnochila chlorodia (Mannerheim) (Coleoptera: Ostomidae), in ponderosa pine forests of northcentral Arizona. We quantified beetle flight activity using data loggers and pheromone-baited funnel traps at 18 sites over 4 yr. Ambient air temperature was monitored using temperature data loggers located in close proximity to funnel traps. We analyzed degree-day accumulation and differences between minimum, average, and maximum ambient temperature for the week before and week of first beetle capture to calculate flight temperature thresholds. Degree-day accumulation was not a good predictor for initiation of beetle flight. For all species analyzed other than D. adjunctus Blandford, beetles were captured in traps only when springtime temperatures exceeded 15.0 degrees C. D. adjunctus was collected when maximum temperatures reached only 14.5 degrees C. Once initial flights had begun, beetles were often captured when maximum ambient air temperatures were below initial threshold temperatures. Maximum and average air temperatures were a better predictor for beetle flight initiation than minimum temperature. We establish a temperature range for effective monitoring of bark beetles and their predators, and we discuss the implications of our results under climate change scenarios.  相似文献   
8.
9.
Sun C  Gaylord BS  Hong JW  Liu B  Bazan GC 《Nature protocols》2007,2(9):2148-2151
A fluorescence-based microarray technique that does not require target DNA labeling is detailed. This 'label-free' approach utilizes a cationic, water-soluble conjugated polymer PFBT (poly[9,9'-bis(6'-(N,N,N-trimethylammonium)hexyl)fluorene-co-alt-4,7-(2,1,3-benzothiadiazole) dibromide]), and neutral PNA (peptide nucleic acid) hybridization probes. DNA hybridization to immobilized PNA spots results in a change in the net charge at that particular surface. Electrostatic interactions between the cationic polymer and negatively charged DNA bind the polymer to the hybrid DNA/PNA complex. By exciting the conjugated polymer at 488 nm on a commercial microarray scanner, the presence of the target is directly indicated by the fluorescence emission of the polymer. This feature eliminates the necessity of target labeling required in traditional microarray protocols. There are five steps involved in the procedure before scanning or imaging the array: (i) slide hydration, (ii) target hybridization, (iii) post-hybridization washing, (iv) polymer application and (v) polymer washing. Each step takes 20 min to 1 h. The overall protocol requires approximately 2-3 h.  相似文献   
10.

Introduction

Exercise training has emerged as a promising therapeutic strategy to counteract physical dysfunction in adult systemic lupus erythematosus. However, no longitudinal studies have evaluated the effects of an exercise training program in childhood-onset systemic lupus erythematosus (C-SLE) patients. The objective was to evaluate the safety and the efficacy of a supervised aerobic training program in improving the cardiorespiratory capacity in C-SLE patients.

Methods

Nineteen physically inactive C-SLE patients were randomly assigned into two groups: trained (TR, n = 10, supervised moderate-intensity aerobic exercise program) and non-trained (NT, n = 9). Gender-, body mass index (BMI)- and age-matched healthy children were recruited as controls (C, n = 10) for baseline (PRE) measurements only. C-SLE patients were assessed at PRE and after 12 weeks of training (POST). Main measurements included exercise tolerance and cardiorespiratory measurements in response to a maximal exercise (that is, peak VO2, chronotropic reserve (CR), and the heart rate recovery (ΔHRR) (that is, the difference between HR at peak exercise and at both the first (ΔHRR1) and second (ΔHRR2) minutes of recovery after exercise).

Results

The C-SLE NT patients did not present changes in any of the cardiorespiratory parameters at POST (P > 0.05). In contrast, the exercise training program was effective in promoting significant increases in time-to-exhaustion (P = 0.01; ES = 1.07), peak speed (P = 0.01; ES = 1.08), peak VO2 (P = 0.04; ES = 0.86), CR (P = 0.06; ES = 0.83), and in ΔHRR1 and ΔHRR2 (P = 0.003; ES = 1.29 and P = 0.0008; ES = 1.36, respectively) in the C-SLE TR when compared with the NT group. Moreover, cardiorespiratory parameters were comparable between C-SLE TR patients and C subjects after the exercise training intervention, as evidenced by the ANOVA analysis (P > 0.05, TR vs. C). SLEDAI-2K scores remained stable throughout the study.

Conclusion

A 3-month aerobic exercise training was safe and capable of ameliorating the cardiorespiratory capacity and the autonomic function in C-SLE patients.

Trial registration

NCT01515163.  相似文献   
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