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71.
We sought to define objective indicators of the resolution of Pseudomonas aeruginosa endobronchial infection in patients with cystic fibrosis. We prospectively studied 75 patients admitted for treatment of a pulmonary exacerbation and quantitated sputum bacterial density, DNA content, and the concentration of albumin and total protein in sputum, and compared these values with clinical evaluation. Eleven of the 75 patients had systemic signs, fever, and leukocytosis, which we arbitrarily defined as due to endobronchial infection. At the end of hospitalization, these 11 patients were afebrile, had peripheral leukocyte counts in the normal range, and were judged improved. Sputum P. aeruginosa density, DNA content, and total protein content on admission were similar in the two illness groups. Hospitalization and parenteral antibiotic administration for an average of 14.6 days were associated with improved pulmonary function in all 75 subjects (P values for forced vital capacity, forced expiratory volume at 1 second, and peak expiratory flow rate were all less than 0.001). With improvement, there was a decrease in sputum P. aeruginosa density (mean of both groups decreased from 10(7.80) CFU/g on admission to 10(5.96) CFU/g; P less than 0.001), and a decreased DNA concentration (overall mean 4.73 +/- 4.75 on admission to 2.76 +/- 2.49 mg/g; P less than 0.002). The decrease in sputum total protein concentration for both groups was not significant (overall mean 60.5 +/- 48.4 to 43.9 +/- 38.2 mg/g; P = 0.06). Sputum albumin concentrations did not change in either group. We conclude that in cystic fibrosis subjects with a pulmonary exacerbation, bacterial density, sputum DNA and protein content decrease with hospitalization and parenteral antibiotic therapy. At the end of treatment, these indices of sputum infection and inflammation correlate with improved pulmonary function and clinical improvement. These changes are independent of the presence or absence of fever on admission.  相似文献   
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The emergence of SARS-CoV-2 triggering the COVID-19 pandemic ranks as arguably the greatest medical emergency of the last century. COVID-19 has highlighted health disparities both within and between countries and will leave a lasting impact on global society. Nonetheless, substantial investment in life sciences over recent decades has facilitated a rapid scientific response with innovations in viral characterization, testing, and sequencing. Perhaps most remarkably, this permitted the development of highly effective vaccines, which are being distributed globally at unprecedented speed. In contrast, drug treatments for the established disease have delivered limited benefits so far. Innovative and rapid approaches in the design and execution of large-scale clinical trials and repurposing of existing drugs have saved many lives; however, many more remain at risk. In this review we describe challenges and unmet needs, discuss existing therapeutics, and address future opportunities. Consideration is given to factors that have hindered drug development in order to support planning for the next pandemic challenge and to allow rapid and cost-effective development of new therapeutics with equitable delivery.  相似文献   
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Summary

The role of peroxide and catalase on NUV radiation sensitivity was examined in two repair competent E. coli strains, AB1157 and B/r. Exponential phase B/r is considerably more sensitive to NUV radiation than exponential phase AB1157. However, resistance to 5 mmol dm?3 H2O2 was induced in both AB1157 and B/r by pretreating growing cells with 30 μmol dm?3 H2O2. Pretreatment also induced resistance to broad-band NUV radiation in these strains. The addition of catalase to the post-irradiation plating medium increased survival to the same extent as that provided by pretreatment with 30 μmol dm?3 H2O2, in both strains. The NUV radiation sensitivity seen in B/r does not appear to be due to a deficiency in enzymes that scavenge H2O2, as a catalase deficient mutant, E. coli UM1, is more resistant to NUV radiation than B/r. Also, assays for H2O2 scavenging ability show little difference between AB1157 and B/r in this respect. Two hypotheses are put forward to account for the sensitivity of exponential phase B/r. Whilst it is apparent that peroxides and catalase do have a role in NUV radiation damage, it is clear that other factors also influence survival under certain conditions.  相似文献   
76.
BackgroundTuberous sclerosis complex (TSC) is a neurogenetic syndrome due to loss-of-function mutations in TSC2 or TSC1, characterized by tumors at multiple body sites, including facial angiofibroma (FAF). Here, an ultrasensitive assessment of the extent and range of UV-induced mutations in TSC facial skin was performed.MethodsA multiplex high-sensitivity PCR assay (MHPA) was developed, enabling mutation detection at extremely low (<0.1%) variant allele frequencies (VAFs).ResultsMHPA assays were developed for both TSC2 and TP53, and applied to 81 samples, including 66 skin biopsies. UV-induced second-hit mutation causing inactivation of TSC2 was pervasive in TSC facial skin with an average of 4.8 mutations per 2-mm biopsy at median VAF 0.08%, generating more than 150,000 incipient facial tumors (subclinical “micro-FAFs”) in the average TSC subject. The MHPA analysis also led to the identification of a refined UV-related indel signature and a recurrent complex mutation pattern, consisting of both a single-nucleotide or dinucleotide variant and a 1- to 9-nucleotide deletion, in cis.ConclusionTSC facial skin can be viewed as harboring a patchwork of clonal fibroblast proliferations (micro-FAFs) with indolent growth, a small proportion of which develop into clinically observable FAF. Our observations also expand the spectrum of UV-related mutation signatures.FundingThis work was supported by the TSC Alliance; the Engles Family Fund for Research in TSC and LAM; and the NIH, National Heart, Lung, and Blood Institute (U01HL131022-04 and Intramural Research Program).  相似文献   
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This study was conducted to 1) assess the effectiveness of an experimental two-way cable TV system in reaching the older people for whom it was designed, and 2) assess the attraction of this locally-based age-targeted system for its viewers. The study evaluates the system's effectiveness in reaching its target audience by examining information about the types of viewers—both younger and older—who have been attracted to the system. In addition, differences in factors that predict viewing frequency for younger and older people are used to illuminate life stage differences in people's attraction to locally-based TV programming. Findings show that the system had successfully reached its target audience within two years of inception. Watching the interactive TV programs because of the system's provision of information about local events and because of the senior citizens' focus strongly predicted viewing frequency for both older and younger respondents. The ability of locally-based interactive TV programming to serve social and informational needs of older people which are unmet by traditional broadcast television is discussed.  相似文献   
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Residents near the Trecatti landfill site located in South Wales, United Kingdom, expressed concern about odors and health effects they attributed to site emissions. The authors compared routinely collected, population-based, health data from potentially exposed electoral wards (i.e., United Kingdom electoral tracts) with data from both wards nearby, matched for socioeconomic deprivation scores, and with wards where residents were likely to attend the same hospital. Mortality rates were higher for all causes and neoplastic diseases (but not respiratory disease) in the exposed wards, but there was no change in rates after the site opened. Hospital data revealed a transient increase in admissions for asthma during the 3 yr that preceded the peak in odor complaints. The birth prevalence of congenital malformations was raised in the exposed wards, but the authors could not exclude a possible artifact resulting from differences in reporting practices between hospitals. The absence of environmental monitoring in the community during the period of public concern was a significant weakness of this study.  相似文献   
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A highly detailed account of the psychotherapy of one female hysterioa treatment failureis the stimulant for discussion of the genetics and dynamics of this nosology. The patient's symptomatology includes feelings of unreality, seizures, an embryo dual personality, and frigidity. Hypnosis revealed the experimental basis for these symptoms and associated adjustment di5iculties. The dynamics bear a remarkable resemblance to those advanced by Freud and Breuer, though issue is taken with several fundamental psychoanalytic concepts. The Discussion deals largely with the phenomenology of the female hysteric. It is concluded that the seemingly favorable prognosis of the hysteric is illusionary if the goal is characterologic change.  相似文献   
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