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51.
A phase I clinical trial was initiated to treat patients with stage IV B-derived chronic lymphocytic leukemia (CLL) with the IgG2a murine monoclonal antibody T101. This antibody binds to a 65,000-mol wt (T65) antigen found on normal T lymphocytes, malignant T lymphocytes, and B- derived CLL cells. All of the patients had a histologically confirmed diagnosis of advanced B-derived CLL and were refractory to standard therapy, and more than 50% of their leukemia cells reacted with the T101 antibody in vitro. The patients received T101 antibody two times per week, over two to 50 hours by intravenous administration in 100 mL of normal saline containing 5% human albumin. Twelve patients were treated with a fixed dosage of 1, 10, 50, or 100 mg, and one patient was treated with 140 mg of antibody. It was demonstrated that patients given two-hour infusions of 50 mg developed pulmonary toxicity, with shortness of breath and chest tightness. This toxicity was eliminated when infusions of 50 or 100 mg of T101 were prolonged to 50 hours. All dose levels caused a rapid but transient decrease in circulating leukemia cell counts. In vivo binding to circulating and bone marrow leukemia cells was demonstrated at all dose levels with increased binding at higher dosages. Antimurine antibody responses were not demonstrated in any patients at any time during treatment. Circulating free murine antibody was demonstrated in the serum of only the two patients treated with 100 mg of antibody as a 50-hour infusion and the patient treated with 140 mg of antibody over 30 hours. Antigenic modulation was demonstrated in patients treated at all dose levels but was particularly apparent in patients treated with prolonged infusions of 50 and 100 mg of antibody. We were also able to demonstrate antigenic modulation in lymph node cells, which strongly suggests in vivo labeling of these cells. Overall, T101 antibody alone appears to have a very limited therapeutic value for patients with CLL. The observations of in vivo labeling of tumor cells, antigenic modulation, antibody pharmacokinetics, toxicity, and antimurine antibody formation may be used in the future for more effective therapy when drugs or toxins are conjugated to the antibody.  相似文献   
52.
Objectives:The isotope bone scan (IBS) is the gold-standard imaging modality for detecting skeletal metastases as part of prostate cancer staging. However, its clinical utility for assessing skeletal metastatic burden is limited due to the need for subjective interpretation. We designed and tested a novel custom software tool, the Metastatic Bone Scan Tool (MetsBST), aimed at improving interpretation of IBSs, and compared its performance with that of an established software programme.Methods:We used IBS images from 62 patients diagnosed with prostate cancer and suspected bone metastases to design and implement MetsBST in MATLAB by defining thresholds used to identify the texture and size of metastatic bone lesions. The results of MetsBST were compared with those of the commercially available automated Bone Scan Index (aBSI) with regression analysis.Results:There was strong agreement between the MetsBST and aBSI results (R2 = 0.9189). In a subregional analysis, MetsBST quantified the extent of metastatic disease in multiple bone sites in patients receiving multimodality therapy (radium-223 and external beam radiotherapy) to illustrate the differences in bone metastatic response to different treatments.Conclusion:The results of MetsBST and the commercial software aBSI were highly consistent. MetsBST introduces novel clinical utility by its ability to differentiate between the responses of different bone metastases to multimodality therapies.Advances in knowledge:MetsBST reduces the variability in assessment of tumour burden caused by subjective interpretation. Therefore, it is a useful aid to physicians reporting nuclear medicine scans, and may improve decision-making in the treatment of metastatic prostate cancer.  相似文献   
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In this study, Tithonia diversifolia Helms. (A Gray), Aloe secundiflora (Miller) and Azadirachta indica (A. Juss) plant extracts were used to make herbal soaps while Thevetia peruviana (Schum) seed oil was used to make a herbal lotion for skincare. The soaps were tested for the growth inhibition of Escherichia coli, and Candida albicans. The lotion was evaluated against Staphylococcus aureus and E.coli. Although Tithonia diversifolia soap exhibited the highest inhibitory effect on the test bacterial strains, it had the least inhibition against C. albicans. Results from this study indicated that the ‘Tithonia diversifolia’ soap would have superior skin protection against the tested bacteria but would offer the least skin protection against C. albicans. The herbal lotion inhibited S. aureus and E. coli in a concentration dependent manner, however, the inhibitory effect was more pronounced on S. aureus.  相似文献   
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Ventilator-associated pneumonia (VAP) is a common cause of morbidity, antibiotic use, increased length of stay and, possibly, increased mortality in ICU patients. Colonization of the oropharyngeal cavity with potentially pathogenic micro-organisms is instrumental in the pathogenesis of VAP, and selective oropharyngeal decontamination (SOD) with antibiotics (AB-SOD) or antiseptics, such as chlorhexidine gluconate (CHX-SOD), has been associated with reduced incidences of VAP. In a recent issue of Critical Care Scannapieco and colleagues investigated differences in oropharyngeal colonization between mechanically ventilated patients receiving oropharyngeal decontamination with 0.12% CHX-SOD either once or twice daily compared to placebo. CHX-SOD was associated with a reduction in Staphylococcus aureus colonization, but the study was underpowered to demonstrate a reduction in VAP incidence. We urgently need well-designed and adequately powered studies to evaluate the potential benefits of CHX-SOD on patient outcome in ICUs.  相似文献   
56.
Background Perceived age is important to women and is a primary driver for topical product use and facial cosmetic surgery. Changes in facial features and biophysical skin parameters with chronological age and their associations with perceived age have not been described in Asian populations. Objective To investigate the relationship between biophysical properties of the skin, visual features of skin ageing and perceived facial age in Chinese women. Methods Facial photographs were collected of 250 Chinese women, aged 25–70 years in Shanghai, China. The perceived facial age was determined and related to the chronological age for each participant and to a range of visual assessments of skin appearance and objective biophysical measurements of the skin. The profile of changes in these parameters with age was investigated together with the differences in those parameters for women judged to look younger than their chronological age and those judged to look older than their chronological age. Results Large discrepancies in perceived age (up to 29 years) were found in women of the same chronological age. Each objective skin measure and visual assessment parameter had a stronger correlation with perceived age than with chronological age. The strongest relationships to perceived age were for wrinkles and hyperpigmentation. Skin colour, hydration and trans‐epidermal water loss (TEWL) had weaker associations with perceived age. Women judged to look older than their chronological age had significantly higher scores than those judged to look younger for coarse wrinkles and hyperpigmentation across all age groups. The appearance differences between these groups were evident in composite facial images of the same average chronological age. Conclusions We have identified the skin attributes which differ with perceived age in Chinese women. Perceived age is a better measure of the biological age of facial skin than is chronological age in this population.  相似文献   
57.
Previously, we showed that neonatal isolation (1-h isolation/day from dam, litter, and nest on PND 2–9) facilitates cocaine self-administration and increases extracellular dopamine responses in ventral striatum after stimulant administration in adulthood. Recent studies suggest that enduring alterations in neurobehavioral responses associated with early life manipulations reflect changes in maternal behavior. Thus, we sought to determine if neonatal isolation alters maternal care and if dams with neonatal isolation experience as pups showed differential maternal care towards their pups. In Experiment 1, litters were assigned to one of three conditions: neonatal isolation, handled (5-min separation of dam from litter), or non-handled (no separation). Maternal behaviors were rated on PND 2–9 for 60-min immediately following reunion of mother and litter. In Experiment 2, female rats with or without neonatal isolation experience were assigned to either the neonatal isolation or non-handled litter condition and maternal behaviors rated. Dams of isolated and handled litters spent more time licking pups and less time picking up pups to put outside the nest than dams of non-handled litters. Further, dams of isolated and handled vs. non-handled litters showed less non-maternal behaviors of burrowing and grooming. Neonatal isolation-experienced dams with isolated litters failed to increase pup-licking and decrease non-maternal behaviors. Rather, these dams picked up pups to place outside the nest more than non-handled-experienced dams. Neonatal isolation alters maternal behavior that, in turn, may shape neurobehavioral responses of offspring including effects on maternal care. Such changes may reflect epigenetic effects resulting from changes in maternal behavior.  相似文献   
58.
Background: Ventilator frequency is one of the determinants of tidal volume delivery during high‐frequency ventilation. Clinicians increasingly use data on ventilator displays to inform their decisions. Aim: To measure the frequencies delivered by the Dräger Babylog 8000plus ventilator when used in high‐frequency mode. Methods: Ventilator waveforms using a test lung were recorded at the full range of settings 5–20 Hz using Spectra software at 1000 Hz. The changes in frequency produced by a 1‐ Hz change in set frequency were calculated. Actual and displayed frequencies were compared. Results: For settings up to 12 Hz, median (range) difference between set and delivered frequencies was 0 (?0.4 to +0.1) Hz. Above 12 Hz, delivered frequency varied by ?0.3 (?1.9 to +0.3) Hz. For 1‐ Hz changes in frequency settings, in the range 5–12 Hz, 1‐ Hz changes produced a change in delivered frequency of 1.0 (0.6–1.4) Hz. Above 12 Hz, the corresponding changes were 0.7 (0–2.9) Hz. The ventilator displays the set frequency during operation rather than the delivered frequency. Conclusion: At 12 Hz and below, the differences between set and delivered frequencies were relatively small compared with those at 13 Hz and higher. Above 13 Hz, the difference between set and delivered frequencies was up to 2.9 Hz. Some frequency setting changes did not result in a change in delivered frequency.  相似文献   
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BACKGROUND: The workplace provides a useful setting for early identification and intervention with individuals who have unhealthy lifestyles. The objective was to evaluate the effects of a workplace-based lifestyle intervention (Workscreen) to reduce excessive drinking. METHOD: There were eight Australia Post networks randomly allocated to experimental and control conditions, comprising 67 worksites and 1206 employees. The experimental condition involved a broad spectrum lifestyle campaign, incorporating support from management, employee awareness of health, and brief interventions for high-risk behaviors, including excessive alcohol use. Focus groups identified relevant cultural factors. Changes in workplace culture and employee behavior were assessed 10 months after baseline. Males and females were analyzed separately. RESULTS: Over half of APOST employees participated at each screening point. In the experimental condition 61% of employees overall and 58% of those identified as excessive drinkers in Phase 1 responded to the lifestyle campaign by attending health assessments. Analyses focusing on the organization as a whole did not reveal significant reductions in excessive alcohol consumption among men or women. However, a significant reduction in number of drinks was observed in the experimental condition among women for whom completion of baseline and follow-up could be confirmed (P < 0.001). CONCLUSIONS: The present study indicates that a workplace-based lifestyle campaign can assist self-selected employees in reducing their alcohol consumption. There was a moderately high level of participation among those identified as drinking excessively, which supports our approach of embedding a low-intensity alcohol program within the context of a broader health promotion campaign.  相似文献   
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