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11.
Journal of NeuroVirology - Rapid maturation of major white matter pathways occurs in the first 2 years of life, indicating a critical neuronal developmental period. The impact of...  相似文献   
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The aim of this study was to compare the type and antimicrobial resistance patterns of bacteria cultured from blood or respiratory tract secretions by HIV status and the use of trimethoprim-sulphamethoxazole (TMP-SMX) prophylaxis in children hospitalized with community-acquired pneumonia. During a 1-year prospective study in Cape Town, South Africa, 250 children [median aged 6 (3-16) months] hospitalized with pneumonia were enrolled; 151 (60.4 per cent) were HIV-infected. The incidence of bacteremia [35 of 244 cultures (14.3 per cent)] did not differ by HIV status. Bacteria were cultured in 17 of 32 (53 per cent) bronchoalveolar lavage specimens (BAL), 128 of 210 (61 per cent) induced sputa and 166 of 231 (71 per cent) nasopharyngeal specimens (NPAs). The type and number of bacteria in respiratory secretions did not differ by HIV status, except for a higher rate of Staphylococcus aureus in sputum or BAL [22 of 146 (15 per cent) vs. 3 of 96 (3 per cent), p = 0.003] and NPAs [41 of 135 (30 per cent) vs. 9 of 96 (9 per cent), p < 0.001] of HIV-positive children. The use of TMP-SMX prophylaxis in HIV-infected children was associated with an increased nasopharyngeal carriage of S. aureus [22 of 51 (43 per cent) vs. 17 of 79 (22 per cent), p = 0.009]. The rising prevalence of HIV infection and the use of TMP-SMX prophylaxis may alter the spectrum of colonizing and pathogenic bacteria in children in developing countries.  相似文献   
14.
Childhood pulmonary TB (PTB) is under diagnosed, in part due to difficulties in obtaining microbiological confirmation. However, given the poor specificity of clinical diagnosis, microbiological confirmation and drug susceptibility testing is important in guiding appropriate therapy especially in the context of drug resistant TB. Confirmation is often possible, even in infants and young children, if adequate specimens are collected. Culture yield varies with the severity of illness, specimen type and culture method. Induced sputum is recognised as a safe procedure with a high diagnostic yield. Advances include optimised protocols for smear microscopy and modified culture techniques, such as the Microscopic Observation Drug Susceptibility Assay. Detection of Mycobacterium tuberculosis nucleic acid in respiratory specimens has high specificity but relatively poor sensitivity, particularly for smear negative disease. The recent development of an integrated specimen processing and real-time PCR testing platform for M. tuberculosis and rifampicin resistance is an important advance that requires evaluation in childhood TB.  相似文献   
15.
The purpose of this study was to see whether menarcheal age assessment by means of the most frequently used methods that were conducted every time on the same group of girls would yield the same results. One hundred and one Polish girls, whose ages at menarche were recorded in a longitudinal study between 1976 and 1990, were asked to recall the age of menarche in 2004. The mean menarcheal ages of those women were calculated by means of the probit (PA), prospective (AA), retrospective method without age correction (RA), and retrospective method with the recall age corrected by 0.5 year (RcA). The PA, AA, and retrospective methods: RA and RcA revealed results: 13.14 +/- 1.1; 13.10 +/- 1.1; 13.12 +/- 1.36, and 14.39 +/- 1.34 years, respectively. The menarcheal AA was insignificantly different from the PA (95% CI) and RA. The RcA was significantly higher than the AA and RA (P = 0.05). The correlation coefficient (r) between AA and RA was 0.70. Only 16% of the interviewed women accurately remembered the date of their menarche, 63% of them missed their menarche time by about 1 year, whereas 22% were wrong by 2 and more years. (1) The PA and the AA method yield comparable results when estimating menarcheal age. (2) The menarcheal age determined by the retrospective methods is not very reliable and the application of age correction overestimates the results.  相似文献   
16.

Objectives

Long noncoding RNAs (lncRNA) are a type of noncoding RNA that comprise of longer than 200 nucleotides sequences. They can regulate chromosome structure, gene expression and play an essential role in the pathophysiology of human diseases, especially in tumorigenesis and progression. Nowadays, they are being targeted as potential biomarkers for various cancer types. And many research studies have proven that lncRNAs might bring a new era to cancer diagnosis and support treatment management. The purpose of this review was to inspect the molecular mechanism and clinical significance of long non-coding RNA- differentiation antagonizing nonprotein coding RNA(DANCR) in various types of human cancers.

Materials and methods

In this review, we summarize and figure out recent research studies concerning the expression and biological mechanisms of lncRNA-DANCR in tumour development. The related studies were obtained through a systematic search of PubMed, Embase and Cochrane Library.

Results

Long non-coding RNAs-DANCR is a valuable cancer-related lncRNA that its dysregulated expression was found in a variety of malignancies, including hepatocellular carcinoma, breast cancer, glioma, colorectal cancer, gastric cancer, and lung cancer. The aberrant expressions of DANCR have been shown to contribute to proliferation, migration and invasion of cancer cells.

Conclusions

Long non-coding RNAs-DANCR likely serves as a useful disease biomarker or therapeutic cancer target.  相似文献   
17.

Purpose

Increasingly HIV-infected children can be expected to require surgery. The aim of this study was to compare the outcome of HIV-infected and HIV-unexposed children undergoing surgery.

Patients and methods

A prospective study of children less than or equal to 60?months admitted to a tertiary pediatric surgical service from July 2004 to July 2008. Children underwent age-definitive HIV testing and were followed up postoperatively for complications, length of stay and mortality.

Results

Three hundred and twenty-seven children were enrolled: 82 (23?%) HIV-infected and 245 (67?%) were HIV-unexposed. Eighty-four (26?%) children were malnourished, which was higher in the HIV-infected group [41 (50.0?%) vs. 43 (17.5?%), relative risk (RR) 2.9; 95?% confidence interval (CI) 2.0–4.1; p?<?0.0001]. Three hundred and twenty-eight surgical procedures were performed. A similar number of major [28 (34.2?%) vs. 64 (26.1?%); p?=?0.2] and emergency procedures [37 (45.1?%) vs. 95 (38.8?%); p?=?0.34] were performed in each group. HIV-infected children had a higher rate of contamination at surgery [40 (48.7?%) vs. 49 (20?%); RR 2.43 (CI 1.7–3.4); p?<?0.0001]. There were more complications in the HIV-infected group [34 (41.5?%) vs. 14 (5.7?%); RR 7.3 (CI 4.1–12.8); p?<?0.0001]. The most common complications were surgical site complications 30 (55?%), followed by postoperative infections, 19 (34?%). Infections with drug-resistant organisms occurred more commonly in HIV-infected children [11/19 (58?%) vs. 2/13 (15?%); RR 3.8 (CI 1.3–14.2); p?=?0.02]. The median length of hospital stay was longer in the HIV-infected group [4 (IQR 2–14) vs. 2 (IQR 1–4) days; p?=?0.0001]. There was a higher mortality amongst the HIV-infected group [6 (7.3?%) vs. 0 (0?%); p?<?0.0001].

Conclusion

HIV-infected children have a higher rate of postoperative complications and mortality compared with HIV-unexposed children.  相似文献   
18.
BACKGROUND: Inhaled bronchodilator treatment given via a metered dose inhaler (MDI) and spacer is optimal for relief of bronchoconstriction. Conventional spacers are expensive or unavailable in developing countries, but there is little information on the efficacy of low-cost spacers in young children. OBJECTIVE: To compare the response to bronchodilator treatment given via a conventional or a low-cost bottle spacer METHODS: A randomised controlled trial of the efficacy of a conventional spacer compared with a bottle spacer for bronchodilator treatment in young children with acute lower airway obstruction. Bronchodilator treatment was given from an MDI via an Aerochamber or a bottle spacer. Clinical score and oximetry recording were carried out before and after 15 min of treatment. MDI-spacer treatment was repeated up to three times, depending on clinical response, after which nebulisation was used. The primary outcome was hospitalisation. RESULTS: 400 children, aged (median (25th-75th centile)) 12 (6-25) months, were enrolled. The number of children hospitalised (n = 60, 15%) was identical in the conventional and bottle spacer groups (n = 30, 15% in each). Secondary outcomes including change in clinical score (-2 (-3 to -1)), oxygen saturation (0 (-1 to 1)) and number of bronchodilator treatments (2 (1 to 3)) were similar in both groups. Oral corticosteroids, prescribed for 78 (19.5%) children, were given to a similar number in the conventional (37 (18.5%)) and bottle spacer groups (41 (20.5%)). CONCLUSION: A low-cost bottle spacer is as effective as a conventional spacer for bronchodilator treatment in young children with acute obstruction of the lower airways.  相似文献   
19.
The effects of melatonin on platelet aggregation and thromboxane-B2 (TxB2) production induced by 1-4 x 10(-6) M adenosine diphosphate (ADP) or 0.6 x 10(-3) M arachidonic acid (AA) were assessed in platelet-rich plasma (PRP). Micromolar concentrations of melatonin inhibited in a dose-dependent way ADP-induced platelet aggregation with individual inhibitions 40% or more at 10(-6)-10(-5) M. A significant depression of AA-induced platelet aggregation was observed only at 10(-5)-10(-4) M melatonin. Morning (0830 h)-evening (1800 h) studies of ADP-induced platelet aggregation in seven normal men showed a higher sensitivity at 1800 h when analyzed as a global inhibitory effect of melatonin (P less than 0.01). Moreover, only during the evening hours did melatonin induce reversible aggregation, an index of inhibition of the platelet secretory process elicited by ADP exposure. No diurnal variability in melatonin inhibition of AA-induced aggregation was detected. TxB2 production elicited by AA in the evening was inhibited significantly in a concentration-related manner by a 2-min preincubation with 10(-9)-10(-5) M melatonin, while during the morning hours the inhibition was significant only at 10(-6) M or higher melatonin concentrations. In the case of ADP, the inhibition of TxB2 release attained significance at 10(-5)-M (0830 h) or 10(-6)-M concentrations (1800 h). In the presence of either stimulatory agent, melatonin depression of TxB2 generation was about 2-fold greater at 1800 h than at 0830 h. The diurnal changes in melatonin effect on TxB2 production were also observed in thrombin-stimulated washed platelets. The present data indicate the existence of circadian variations in platelet responsiveness to melatonin in humans.  相似文献   
20.
BACKGROUND: Accreditation Council on Graduate Medical Education work-hour restrictions are aimed at improving patient safety and resident well-being. Although surgical trainees will be dramatically affected by these changes, no comprehensive assessment of their well-being has been recently attempted. STUDY DESIGN: A multicenter study of psychological well-being of surgical residents (n = 108) across four US training programs before implementation of the 80-hour work week was performed using two validated surveys (Symptom Checklist-90-R [SCL-90-R] and Perceived Stress Scale [PSS]) during academic year 2002-03. Societal normative populations served as controls. Primary outcomes measures were psychologic distress (SCL-90-R) and perceived stress (PSS). Secondary outcomes measures (SCL-90-R) were somatization, depression, anxiety, interpersonal sensitivity, hostility, obsessive-compulsive behavior, phobic anxiety, paranoid ideation, and psychoticism. The impact of personal variables (age, gender, marital status) and programmatic variables (level of training, laboratory experience, institution) was assessed. RESULTS: Mean psychologic distress was significantly higher in general surgery residents than in the normative population (p < 0.0001), with 38% scoring above the 90th percentile and 72% above the 50th percentile. Mean perceived stress among surgery residents was higher than historic controls (p < 0.0001), with 21% scoring above the 90th percentile and 68% above the 50th percentile. Among secondary outcomes, eight of nine symptom dimensions were significantly higher in surgical residents than in societal controls. In subgroup analyses, male gender was associated with phobic anxiety (p < 0.001) and anxiety (p < 0.05), and junior level of training (PGY 1 to 3) with anxiety (p < 0.05), obsessive-compulsive behavior (p < 0.05), and interpersonal sensitivity (p < 0.05). CONCLUSIONS: More than one-third of general surgery residents meet criteria for clinical psychologic distress. Surgery residents perceive significantly more stress than societal controls. Both personal and programmatic variables likely affect resident well-being and should be considered in assessing the full impact of Accreditation Council on Graduate Medical Education directives and in guiding future restructuring efforts.  相似文献   
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