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51.
52.
Anam Tariq Hannah Kim Hashim Abbas Gregory M. Lucas Mohamed G. Atta 《Expert opinion on pharmacotherapy》2021,22(1):69-82
ABSTRACT
Introduction
Since the developmentof combined antiretroviral therapy (cART), HIV-associated mortality and the incidence of HIV-associated end-stage kidney disease (ESKD) has decreased. However, in the United States, an increase in non-HIV-associated kidney diseases within the HIV-positive population is expected. 相似文献53.
Shalev H Avraham GP Hershkovitz R Levy A Sheiner E Levi I Tamary H 《European journal of haematology》2008,81(4):317-321
Objectives: Congenital dyserythropoietic anemia type I (CDA I) is a rare inherited disease characterized by moderate to severe macrocytic anemia and abnormal erythroid precursors with nuclear chromatin bridges and spongy heterochromatin. Moderate to severe maternal anemia is a recognized independent risk factor for low birth weight (LBW) and complicated delivery. The aim of the study was to review the outcome of pregnancies in women with CDA I. Methods: The clinical and laboratory records of 28 spontaneous pregnancies in six Bedouin women with CDA I were reviewed. The results were compared with findings from a retrospective review of a large population‐based registry including all pregnancies in Bedouin women during the same 15‐yr period. Results: Eighteen pregnancies in women with CDA I (64%) were complicated. One pregnancy was aborted spontaneously in the first trimester and one resulted in a non‐viable fetus (stillborn at 26 wk). Cesarean section (CS) was performed in 10 pregnancies (36%). Eleven of the 26 newborns (42%) had a LBW: six were born prematurely and five were small for gestational age. The odds ratio for CS in women with CDA I compared with healthy Bedouin women was 4.5 [95% confidence interval (CI) 1.2–10.3], and for a LBW infant, 5.5 (95% CI 2.4–12.3). Careful follow‐up was associated with significantly better fetal outcome (P = 0.05). Conclusions: Pregnancies in women with CDA I are at high risk for delivery‐related and outcome complications. To improve fetal outcome, women with CDA I should be carefully monitored during pregnancy. 相似文献
54.
Coutinho HM McGarvey ST Acosta LP Manalo DL Langdon GC Leenstra T Kanzaria HK Solomon J Wu H Olveda RM Kurtis JD Friedman JF 《The Journal of infectious diseases》2005,192(3):528-536
In a cross-sectional study of 641 Schistosoma japonicum-infected individuals in Leyte, Philippines, who were 7-30 years old, we determined the grade of hepatic fibrosis (HF) by ultrasound and used anthropometric measurements and hemoglobin levels to assess nutritional status. Serum levels of interleukin (IL)-1, IL-6, and IL-10; tumor-necrosis factor (TNF)-alpha; soluble TNF- alpha receptor I; and C-reactive protein (CRP) were measured to examine the association between these markers of inflammation and HF grade. HF was present in 8.9% of the cohort; the majority of cases were mild (grade I), and severe (grade II or grade III) cases occurred only in male individuals. Compared with individuals without HF, those with severe HF--and, to a lesser degree, those with mild HF--had a significantly lower body-mass index (BMI) and BMI z-score, a higher prevalence of anemia, and a higher level of CRP and were more likely to produce IL-6; furthermore, those with severe HF had a significantly higher level of IL-1, compared with those either without HF or with mild HF. These findings suggest that even mild HF is associated with nutritional morbidity and underscore the importance of early recognition and treatment. In addition, our data are consistent with the hypothesis that, by systemically increasing the levels of the proinflammatory cytokines IL-1 and IL-6, HF causes undernutrition and anemia. 相似文献
55.
56.
Pulmonary Langerhans cell histiocytosis: emerging concepts in pathobiology,radiology, and clinical evolution of disease 总被引:3,自引:0,他引:3
Pulmonary Langerhans cell histiocytosis (PLCH) is an uncommon disorder of adult smokers associated with a significant morbidity. Arising from the aberrant accumulation of Langerhans and other immune cells, PLCH tends to cause a relatively isolated pulmonary involvement as compared to other forms of Langerhans cell (LC) and histiocytic disorders. Increased knowledge of cytokine triggers, dendritic cell trafficking, and clonality of LC populations in PLCH have resulted in an improved understanding of the pathobiology of PLCH. High-resolution CT (HRCT) of the chest has led to better appreciation of nodular and cystic radiographic abnormalities characteristic of the disease. Correlation of HRCT abnormalities with lung pathologic changes has led to an improved comprehension of clinical evolution of PLCH. Current clinical predictors for PLCH outcomes remain poor, although long-term follow-up and radiologic monitoring may help to define disease progression. This review discusses advances in PLCH emphasizing the etiopathologic bases of the disease and currently available radiologic modalities for monitoring disease progression. 相似文献
57.
William N. William Jr Xin Zhao Joy J. Bianchi Heather Y. Lin Pan Cheng J. Jack Lee Hannah Carter Ludmil B. Alexandrov Jim P. Abraham David B. Spetzler Steven M. Dubinett Don W. Cleveland Webster Cavenee Teresa Davoli Scott M. Lippman 《Proceedings of the National Academy of Sciences of the United States of America》2021,118(19)
An aneuploid-immune paradox encompasses somatic copy-number alterations (SCNAs), unleashing a cytotoxic response in experimental precancer systems, while conversely being associated with immune suppression and cytotoxic-cell depletion in human tumors, especially head and neck cancer (HNSC). We present evidence from patient samples and cell lines that alterations in chromosome dosage contribute to an immune hot-to-cold switch during human papillomavirus-negative (HPV−) head and neck tumorigenesis. Overall SCNA (aneuploidy) level was associated with increased CD3+ and CD8+ T cell microenvironments in precancer (mostly CD3+, linked to trisomy and aneuploidy), but with T cell-deficient tumors. Early lesions with 9p21.3 loss were associated with depletion of cytotoxic T cell infiltration in TP53 mutant tumors; and with aneuploidy were associated with increased NK-cell infiltration. The strongest driver of cytotoxic T cell and Immune Score depletion in oral cancer was 9p-arm level loss, promoting profound decreases of pivotal IFN-γ-related chemokines (e.g., CXCL9) and pathway genes. Chromosome 9p21.3 deletion contributed mainly to cell-intrinsic senescence suppression, but deletion of the entire arm was necessary to diminish levels of cytokine, JAK-STAT, and Hallmark NF-κB pathways. Finally, 9p arm-level loss and JAK2-PD-L1 codeletion (at 9p24) were predictive markers of poor survival in recurrent HPV− HNSC after anti–PD-1 therapy; likely amplified by independent aneuploidy-induced immune-cold microenvironments observed here. We hypothesize that 9p21.3 arm-loss expansion and epistatic interactions allow oral precancer cells to acquire properties to overcome a proimmunogenic aneuploid checkpoint, transform and invade. These findings enable distinct HNSC interception and precision-therapeutic approaches, concepts that may apply to other CN-driven neoplastic, immune or aneuploid diseases, and immunotherapies.The genetic bases for predisposition, and neoplastic transformation, to cancer have been increasingly well described. However, it remains less clear how early, precancer cells employ these genetic alterations to acquire the characteristic features and properties (1) of malignant disease. For example, studies of the immune landscape led to breakthrough trials of programmed death-1 (PD-1) inhibitors for recurrent, metastatic head and neck squamous cell carcinoma (HNSC) therapy (2–4). This underscores the importance of immune modulation in these tumors, despite a still suboptimal overall response rate of less than 20% in advanced cancers. Immune response within tumors has been observed to be strongest at the earliest neoplastic stages, as reported recently in lung adenocarcinoma precursors (5). As such, new, immune-based strategies could be developed to reduce the high global burden of HNSC, by intercepting the most common precursor of the most common HNSC presentation: HPV− oral squamous cell carcinomas (6–8).Studies of chromosome somatic copy-number (CN) alteration (SCNA) profiles have reported the impact of 3p14, 9p21, or 17p13 loss in molecular models of HNSC progression (9) and risk (10–15). Early studies reported that patients with oral precancers harboring 9p21 and/or 3p14 loss were at significantly greater cancer risk than those with retention at these loci (10, 16). A comprehensive, prospective validation study examined the relative contribution of six candidate chromosome-arm regions. 9p21 loss had the greatest influence on cancer risk (13). The mechanism underlying the association between CN and malignant transformation of precancers, however, is unclear (17–20). Studies of CN-altered neoplastic cells have shown that SCNAs can trigger a cytotoxic response in experimental precancer systems (21, 22) but, paradoxically, were associated with immune evasion (23) and suppression (24) in computational studies of naturally occurring human cancers. The latter, in melanoma, found that nonresponders to PD-1 and CTLA-4 blockade had higher CN alteration and loss burdens, which correlated with immunologically cold tumors, characterized by cytotoxic-cell, marker, and metric reductions, and suppressive microenvironment cell, network, and signal increases (23–26). This SCNA-cold association was particularly strong in our previous, pan-The Cancer Genome Atlas (TCGA) computational study in HNSC (23). These data point to a putative in vivo switch from immune hot-to-cold in the precancer–cancer transition, and raise the hypothesis that SCNAs in precursor lesions contribute to malignant transformation through genomic events and mechanisms that enable the acquisition of immune-suppressive, evasive properties. To test this hypothesis, we evaluated CN influence on immune profiles and outcomes in a large prospective oral precancer patient cohort, and HPV− HNSC (tissue specimens and cell lines) and anti–PD-1–treated recurrent-disease cohorts. 相似文献
58.
Yuanyuan Feng Hannah McGowan Azin Semsar Hamid R. Zahiri Ivan M. George Timothy Turner Adrian Park Andrea Kleinsmith Helena M. Mentis 《International journal of computer assisted radiology and surgery》2018,13(9):1463-1472
Purpose
To assess a virtual pointer in supporting surgical trainees’ development of professional vision in laparoscopic surgery.Methods
We developed a virtual pointing and telestration system utilizing the Microsoft Kinect movement sensor as an overlay for any imagine system. Training with the application was compared to a standard condition, i.e., verbal instruction with un-mediated gestures, in a laparoscopic training environment. Seven trainees performed four simulated laparoscopic tasks guided by an experienced surgeon as the trainer. Trainee performance was subjectively assessed by the trainee and trainer, and objectively measured by number of errors, time to task completion, and economy of movement.Results
No significant differences in errors and time to task completion were obtained between virtual pointer and standard conditions. Economy of movement in the non-dominant hand was significantly improved when using virtual pointer (\(p = 0.012\)). The trainers perceived a significant improvement in trainee performance in virtual pointer condition (\(p < 0.001\)), while the trainees perceived no difference. The trainers’ perception of economy of movement was similar between the two conditions in the initial three runs and became significantly improved in virtual pointer condition in the fourth run (\(p = 0.017\)).Conclusions
Results show that the virtual pointer system improves the trainer’s perception of trainee’s performance and this is reflected in the objective performance measures in the third and fourth training runs. The benefit of a virtual pointing and telestration system may be perceived by the trainers early on in training, but this is not evident in objective trainee performance until further mastery has been attained. In addition, the performance improvement of economy of motion specifically shows that the virtual pointer improves the adoption of professional vision— improved ability to see and use laparoscopic video results in more direct instrument movement.59.
60.
Enhancing social networks: a qualitative study of health and social care practice in UK mental health services 下载免费PDF全文
Martin Webber Hannah Reidy David Ansari Martin Stevens David Morris 《Health & social care in the community》2015,23(2):180-189
People with severe mental health problems such as psychosis have access to less social capital, defined as resources within social networks, than members of the general population. However, a lack of theoretically and empirically informed models hampers the development of social interventions which seek to enhance an individual's social networks. This paper reports the findings of a qualitative study, which used ethnographic field methods in six sites in England to investigate how workers helped people recovering from psychosis to enhance their social networks. This study drew upon practice wisdom and lived experience to provide data for intervention modelling. Data were collected from 73 practitioners and 51 people who used their services in two phases. Data were selected and coded using a grounded theory approach to depict the key themes that appeared to underpin the generation of social capital within networks. Findings are presented in four over‐arching themes – worker skills, attitudes and roles; connecting people processes; role of the agency; and barriers to network development. The sub‐themes which were identified included worker attitudes; person‐centred approach; equality of worker–individual relationship; goal setting; creating new networks and relationships; engagement through activities; practical support; existing relationships; the individual taking responsibility; identifying and overcoming barriers; and moving on. Themes were consistent with recovery models used within mental health services and will provide the basis for the development of an intervention model to enhance individuals’ access to social capital within networks. 相似文献