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101.
Disseminated phaeohyphomycosis is an uncommon infection affecting immunocompetent and immunocompromised individuals in which response to older antifungal agents has been variable. We compared the effect of six days of therapy with caspofungin, posaconazole, and amphotericin B in parallel studies of survival and fungal burden in an immunocompromised mouse model of Exophiala infection. Mice immunocompromised with cyclophosphamide were treated for 6 days starting one day after initiation of infection. Treatment regimens included amphotericin B, caspofungin, and posaconazole. In the survival studies, experimental animals were observed for 14 days. In the fungal burden tests the experimental animals were sacrificed 7 days after infection and brain and kidney burden determined. Treatment with any agent decreased mortality (P < 0.05), with 40%, 30%, and 80% observed survival of the animals treated with amphotericin B, caspofungin, and posaconazole, respectively. Amphotericin B and posaconazole treatment resulted in a decrease in fungal burden compared to untreated controls (P < 0.05). No reduction in fungal burden was noted in the caspofungin group. All three antifungals evaluated improved survival of immunocompromised mice in this otherwise fatal disseminated phaeohyphomycosis. Amphotericin B and posaconazole reduced fungal burden. Posaconazole and caspofungin appear to have potential for use in treatment of this rare infection.  相似文献   
102.
Effects of spaceflight on rhesus quadrupedal locomotion after return to 1G.   总被引:1,自引:0,他引:1  
Effects of spaceflight on Rhesus quadrupedal locomotion after return to 1G. Locomotor performance, activation patterns of the soleus (Sol), medial gastrocnemius (MG), vastus lateralis (VL), and tibialis anterior (TA) and MG tendon force during quadrupedal stepping were studied in adult Rhesus before and after 14 days of either spaceflight (n = 2) or flight simulation at 1G (n = 3). Flight simulation involved duplication of the spaceflight conditions and experimental protocol in a 1G environment. Postflight, but not postsimulation, electromyographic (EMG) recordings revealed clonus-like activity in all muscles. Compared with preflight, the cycle period and burst durations of the primary extensors (Sol, MG, and VL) tended to decrease postflight. These decreases were associated with shorter steps. The flexor (TA) EMG burst duration postflight was similar to preflight, whereas the burst amplitude was elevated. Consequently, the Sol:TA and MG:TA EMG amplitude ratios were lower following flight, reflecting a "flexor bias." Together, these alterations in mean EMG amplitudes reflect differential adaptations in motor-unit recruitment patterns of flexors and extensors as well as fast and slow motor pools. Shorter cycle period and burst durations persisted throughout the 20-day postflight testing period, whereas mean EMG returned to preflight levels by 17 days postflight. Compared with presimulation, the simulation group showed slight increases in the cycle period and burst durations of all muscles. Mean EMG amplitude decreased in the Sol, increased in the MG and VL, and was unchanged in the TA. Thus adaptations observed postsimulation were different from those observed postflight, indicating that there was a response unique to the microgravity environment, i.e., the modulations in the nervous system controlling locomotion cannot merely be attributed to restriction of movement but appear to be the result of changes in the interpretation of load-related proprioceptive feedback to the nervous system. Peak MG tendon force amplitudes were approximately two times greater post- compared with preflight or presimulation. Adaptations in tendon force and EMG amplitude ratios indicate that the nervous system undergoes a reorganization of the recruitment patterns biased toward an increased recruitment of fast versus slow motor units and flexor versus extensor muscles. Combined, these data indicate that some details of the control of motor pools during locomotion are dependent on the persistence of Earth's gravitational environment.  相似文献   
103.
BACKGROUND: Prior investigations have demonstrated a link between quality of life (QOL) deficits and depression. This report elaborates on prior investigations findings by implementation of formal assignment of the diagnosis of depression and a hierarchical approach to assessment of QOL. METHODS: A masters or doctoral level mental health clinician used the SCID to confirm a diagnosis of major depression in ninety psychiatric inpatients. Function was assessed with the PSMS (a measure of ADL), the IADL scale, and the "daily living and role functioning" and the "relation to self and others" subscales of the Basis-32. RESULTS: Patient age and severity of depression were the most consistent predictors of QOL deficits, although the direction of the age-effect on QOL depended on the specific measure of QOL. Increasing severity of depression was consistently associated with worse QOL, and remained significant after adjusting for age. LIMITATIONS: The cross-sectional method of this study limits the inference of causality between depression severity and poor QOL. CONCLUSIONS: QOL deficits in acutely depressed hospitalized patients occur at multiple strata in the hierarchy of behavior and are most consistently influenced by age and severity of depression. The effect of age on QOL in depressed inpatients is complex, and age is not uniformly associated with poor QOL.  相似文献   
104.
105.
The dorsolateral reticular formation of the caudal medulla, the lateral tegmental field (LTF), participates in generating vomiting. LTF neurons exhibited complex responses to vestibular stimulation in decerebrate cats, indicating that they received converging inputs from a variety of labyrinthine receptors. Such a convergence pattern of vestibular inputs is appropriate for a brain region that participates in generating motion sickness. Since responses of brainstem neurons to vestibular stimulation can differ between decerebrate and conscious animals, the current study examined the effects of whole-body rotations in vertical planes on the activity of LTF neurons in conscious felines. Wobble stimuli, fixed-amplitude tilts, the direction of which moves around the animal at a constant speed, were used to determine the response vector orientation, and also to ascertain whether neurons had spatial–temporal convergence (STC) behavior (which is due to the convergence of vestibular inputs with different spatial and temporal properties). The proportion of LTF neurons with STC behavior in conscious animals (25 %) was similar to that in decerebrate cats. Far fewer neurons in other regions of the feline brainstem had STC behavior, confirming findings that many LTF neurons receive converging inputs from a variety of labyrinthine receptors. However, responses to vertical plane vestibular stimulation were considerably different in decerebrate and conscious felines for LTF neurons lacking STC behavior. In decerebrate cats, most LTF neurons had graviceptive responses to rotations, similar to those of otolith organ afferents. However, in conscious animals, the response properties were similar to those of semicircular canal afferents. These differences show that higher centers of the brain that are removed during decerebration regulate the labyrinthine inputs relayed to the LTF, either by gating connections in the brainstem or by conveying vestibular inputs directly to the region.  相似文献   
106.
The present study was undertaken to assess the temporal association between the profiles of serum concentrations of oestradiol-17beta, progesterone, chorionic gonadotrophin (CG) and relaxin in pregnancies established naturally, and after embryo transfer, as well as in failed pregnancies in rhesus monkeys. In naturally mated cycles (group 1) a conception rate of 75% was obtained. In group 1, the mean day of CG detection in serum was 11.5 +/- 1.9 day post-ovulation, and for relaxin, 9.0 +/- 2.5 day post-ovulation. In group 2, embryo transfer to synchronous, non-mated surrogate recipients was performed; seven embryo transfer cycles yielded three pregnancies which were allowed to continue to term and normal infants were delivered. In embryo transfer cycles the mean day of CG detection was 14.8 +/- 1.8 day post- ovulation, and for relaxin, 11.4 +/- 2.6 day post-ovulation. A delay of about 3 days was observed in the appearance in circulation of CG (P < 0.05) and also of relaxin (P < 0.05) between natural mated and embryo transfer conception cycles. Significant differences (P < 0.05 for progesterone and P < 0.03 for oestradiol) were obtained for the areas under the curves for progesterone and oestradiol between days 12 and 16 in conception cycles compared with failed pregnancies. These data provide the first observation of the normal hormonal signals associated with maternal recognition of transferred embryos during the peri- implantation period, and suggest that the use of such an experimental primate embryo transfer model may help to elucidate components of maternal and embryonic signal-response mechanisms during embryo implantation.   相似文献   
107.
108.
Stressed cells undergoing necrosis release molecules that acts as endogenous danger signals to alert and activate innate immune cells. Both HMGB1 and HSP70 are induced in activated monocytes/macrophages and also are released from stressed or injured cells. We investigated whether HMGB1 and HSP70 released from necrotic monocytes/macrophages, can act as danger signals to mediate proinflammatory cytokine responses to bacterial endotoxin or lipopolysaccharide (LPS). We show that cell lysate, obtained from necrotic cells directly stimulates the proinflammatory cytokine and chemokine responses in human monocyte/macrophage cell line, THP-1, as revealed by the induction of TNF-alpha, IL-6 and IL-8 mRNA expression and protein production. In the presence of LPS, necrotic cell lysate induced a more robust increase in all three proteins. We found that HMGB1 and HSP70 were indeed present in the necrotic cell lysate and were responsible for the significant induction of the proinflammatory cytokine expression, as neutralization with antibodies against both proteins blocked the increase in the cytokine production seen after incubating LPS-stimulated cells with the necrotic cell lysate. We also found that the newly identified triggering receptor expressed on myeloid cells-1 (TREM-1) was involved in mediating the HMGB1- and HSP70-induced cytokine production. Blocking TREM-1 on THP-1 cells with a recombinant chimera prevented the increase in cytokine production, while simultaneous blocking of TLR4 and TREM-1 completely abolished the proinflammatory response, suggesting that TREM-1 synergizes with TLR4 to mediate the effects of such signals from necrotic cells. In addition, blocking HMGB1 or HSP70 simultaneously with TREM-1 did not decrease the cytokine level further, confirming the involvement of TREM-1 in mediating the effect of HMGB1 and HSP70. Although the interaction of HMGB1 and HSP70 with TREM-1 induced I kappa B alpha and p38 expression, both of which are required for the inflammatory cytokine expression, blockade of TREM-1 did not affect I kappa B alpha expression but markedly reduced p38 activation, as revealed by Western blot analysis. Together, these results demonstrate that HMGB1 and HSP70 released from necrotic cells function as endogenous danger signals to augment the proinflammatory responses in monocytes/macrophage and that TREM-1 relays such signals to the cytokine expression cascade. This mechanism may contribute to the amplification and persistence of the inflammatory response to bacterial infection.  相似文献   
109.

Background:

Longer-term pharmacologic studies for insomnia in older individuals are sparse.

Objective:

To evaluate the efficacy and safety of 12 weeks of nightly eszopiclone in elderly outpatients with insomnia.

Methods:

Participants (65–85 years) met DSM-IV-TR criteria for insomnia with total sleep times (TST) ≤ 6 h, and wake time after sleep onset (WASO) ≥ 45 min. Participants were randomized to 12 weeks of eszopiclone 2 mg (n = 194) or placebo (n = 194), followed by a 2-week single-blind placebo run-out. Subject-reported measures of sleep (sTST, sleep latency [sSL], sWASO) and daytime function (alertness, concentration, well-being, ability to function) were assessed. AEs were monitored.

Results:

Subjects treated with 2 mg eszopiclone slept longer at night on average and at every individual time point compared to baseline than placebo subjects, as measured by TST over the 12-week double-blind period (P < 0.0001). Mean sTST over the double-blind period for eszopiclone-treated subjects was 360.08 min compared to 297.86 min at baseline, a mean change of 63.24 min. Over the double-blind period, eszopiclone-treated subjects also experienced a significantly greater improvement in sSL compared to placebo, with a mean decrease of 24.62 min versus a mean decrease of 19.92 min, respectively (P = 0.0014). Eszopiclone subjects also experienced a significantly greater decrease in WASO (mean decrease of 36.4 min) compared to placebo subjects (decrease of 14.8 min) (P < 0.0001). Post-discontinuation, sleep parameters were statistically improved versus baseline for eszopiclone (P-values ≤ 0.01), indicating no rebound. The most common AEs (≥ 5%) were headache (eszopiclone 13.9%, placebo 12.4%), unpleasant taste (12.4%, 1.5%), and nasopharyngitis (5.7%, 6.2%).

Conclusion:

In this Phase IV trial of older adults with insomnia, eszopiclone significantly improved patient-reported sleep and daytime function relative to placebo. Improvements occurred within the first week and were maintained for 3 months, with no evidence of rebound insomnia following discontinuation. The 12 weeks of treatment were well tolerated.

Clinical Trial Information:

A Long-Term Safety and Efficacy Study of Eszopiclone in Elderly Subjects With Primary Chronic Insomnia; Registration #NCT00386334; URL - http://www.clinicaltrials.gov/ct2/show/NCT00386334?term=eszopiclone&rank=24

Citation:

Ancoli-Israel S; Krystal AD; McCall WV; Schaefer K; Wilson A; Claus R; Rubens R; Roth T. A 12-week, randomized, double-blind, placebo-controlled study evaluating the effect of eszopiclone 2 mg on sleep/wake function in older adults with primary and comorbid insomnia. SLEEP 2010;33(2):225-234.  相似文献   
110.
The aims of this study were to investigate whether intrafraction prostate motion can affect the accuracy of online prostate positioning using implanted fiducial markers and to determine the effect of prostate rotations on the accuracy of the software‐predicted set‐up correction shifts. Eleven patients were treated with implanted prostate fiducial markers and online set‐up corrections. Orthogonal electronic portal images were acquired to determine couch shifts before treatment. Verification images were also acquired during treatment to assess whether intrafraction motion had occurred. A limitation of the online image registration software is that it does not allow for in‐plane prostate rotations (evident on lateral portal images) when aligning marker positions. The accuracy of couch shifts was assessed by repeating the registration measurements with separate software that incorporates full in‐plane prostate rotations. Additional treatment time required for online positioning was also measured. For the patient group, the overall postalignment systematic prostate errors were less than 1.5 mm (1 standard deviation) in all directions (range 0.2–3.9 mm). The random prostate errors ranged from 0.8 to 3.3 mm (1 standard deviation). One patient exhibited intrafraction prostate motion, resulting in a postalignment prostate set‐up error of more than 10 mm for one fraction. In 14 of 35 fractions, the postalignment prostate set‐up error was greater than 5 mm in the anterior–posterior direction for this patient. Maximum prostate rotations measured from the lateral images varied from 2° to 20° for the patients. The differences between set‐up shifts determined by the online software without in‐plane rotations to align markers, and with rotations applied, was less than 1 mm (root mean square), with a maximum difference of 4.1 mm. Intrafraction prostate motion was found to reduce the effectiveness of the online set‐up for one of the patients. A larger study is required to determine the magnitude of this problem for the patient population. The inability in the current software to incorporate in‐plane prostate rotations is a limitation that should not introduce large errors, provided that the treatment isocentre is positioned near the centre of the prostate.  相似文献   
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