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1.
The main aim of the paper is to discuss current knowledge on how Age Related Macular Degeneration (AMD) affects Dark Adaptation (DA). The paper is divided into three parts. Firstly, we outline some of the molecular mechanisms that control DA. Secondly, we review the psychophysical issues and the corresponding analytical techniques. Finally, we characterise the link between slowed DA and the morphological abnormalities in early AMD.Historically, DA has been regarded as too cumbersome for widespread clinical application. Yet the technique is extremely useful; it is widely accepted that the psychophysically obtained slope of the second rod-mediated phase of the dark adaptation function is an accurate assay of photoreceptor pigment regeneration kinetics. Technological developments have prompted new ways of generating the DA curve, but analytical problems remain. A simple potential solution to these, based on the application of a novel fast mathematical algorithm, is presented. This allows the calculation of the parameters of the DA curve in real time.Improving current management of AMD will depend on identifying a satisfactory endpoint for evaluating future therapeutic strategies. This must be implemented before the onset of severe disease. Morphological changes progress too slowly to act as a satisfactory endpoint for new therapies whereas functional changes, such as those seen in DA, may have more potential in this regard. It is important to recognise, however, that the functional changes are not confined to rods and that building a mathematical model of the DA curve enables the separation of rod and cone dysfunction and allows more versatility in terms of the range of disease severity that can be monitored. Examples are presented that show how analysing the DA curve into its constituent components can improve our understanding of the morphological changes in early AMD. 相似文献
2.
Bashir A. Fomda Nazima Abdullah Yawar B. Mir Gulnaz Bashir Asiya Khan Syed M. Qadri Sonaullah Shah 《Indian journal of medical microbiology》2022,40(2):294-298
PurposeThe clinical manifestations of rickettsial diseases mimic other endemic infections with similar presentations thus posing a serious challenge to clinicians for their diagnosis. For the diagnosis of rickettsial disease serological tests like Weil Felix, ELISA and IFA are used. There are limited studies that have evaluated different serological tests for the diagnosis of rickettsial diseases. Therefore, the present study was undertaken to evaluate the ELISA and Weil Felix test for the diagnosis of rickettsial diseases prevalent in this region.MethodsSamples from 281 patients clinically suspected of rickettsial diseases were tested for spotted fever group (SFG), typhus group (TG) and scrub typhus group (STG) by Weil Felix, ELISA and IFA was taken as the gold standard. Baseline titers and cut-off ODs were calculated by taking samples from healthy blood donors.ResultsThe sensitivity, specificity, positive and negative predictive value of Weil Felix test ranged from 30% to 44%, 83.46%–97.86%, 9%–77%, 92–96% respectively. The sensitivity and specificity, positive and negative predictive value of ELISA ranged from 80.77% to 96.15%, 96.33%–98.43%, 70.21%–88.64%, 92.89%–99.60% respectively. Maximum cross-reactions were observed between SFG and STG by the Weil Felix test and between STG and TG by ELISA.ConclusionsELISA was found to be sensitive and specific for the diagnosis of rickettsial diseases. It is easy to perform, does not require a technical expert for result interpretation and a large number of samples can be processed at a time. 相似文献
3.
《Neuro-Chirurgie》2023,69(1):101397
BackgroundWe previously described a procedure for eliciting deep spatial discrimination of individual segments in the healthy lumbar spine of normal subjects: the percutaneous mechanical provocation (PMP) test. Our goal was to devise a method for accurate identification of the spinal level of pathology in chronic low back pain (CLBP). In the present study, we validated the PMP test, using a subgroup of CLBP patients with isthmic spondylolisthesis (IS). Because there is clinical consensus that IS back pain originates in the slipped segment/disc, the level of pathology can be directly compared to the result of the PMP test. The test is agnostic with respect to the underlying pathological mechanism, and therefore might be useful in identifying the involved segment(s) irrespective of the painful structure.MethodsIn 37 patients with confirmed IS (slippage 3–15 mm), we compared sensitivity between the PMP test, the widely used provocative discography test and the discoblock test.ResultsThe PMP test reliably identified the slip level in patients with IS, with sensitivity of 92%. Accepting the slipped disc as the origin of pain in IS, the sensitivity of the provocative discography and discoblock tests were 49% and 35%, respectively: i.e., too low to be contributive in clinical practice.ConclusionsThe PMP test reliably identified the origin of localized pain in IS as the slip level, but should be used with care in CLBP patients in selecting discogenic pain patients for fusion surgery, since the specificity of the test is not known and it may be positive for any origin of localized pain. 相似文献
4.
5.
Cervical squamous cell carcinoma and endocervical adenocarcinoma (CESC) is the fourth commonest female malignancy worldwide. CESC progresses in immune-microenvironment mainly composed of infiltrating immune and stromal cells. Here, we performed an integrated analysis incorporating the expression profiles from the Cancer Genome Atlas (TCGA) database and scores of immune and stromal cells calculated by Estimation of Stromal and Immune cells in Malignant Tumours using Expression data (ESTIMATE) algorithm. A two-gene signature (CD1C and CD6 genes) was established to predict the prognosis of CESC. Based on this signature, patients were divided into the high- and low-risk groups, and this signature showed good prognostic performance according to the results of Kaplan-Meier analysis and receiver operating characteristic (ROC) analysis in train set and two validation sets. A nomogram was built for evaluating the clinical applicability of this signature. In addition, based on Tumor Immune Estimation Resource (TIMER) database, 2 hub genes showed negative correlations with tumor purity and positive correlations with infiltrating levels of immune filtrating cells. What’s more, we propose new treatment strategies for the two prognostic subtypes. Low- risk patients were found presenting with a higher level of immune checkpoint molecules and showing higher immunogenicity in immunophenoscore (IPS) analysis, which indicated a better response for immunotherapy. Meanwhile, estimated by Genomics of Drug Sensitivity in Cancer (GDSC) database, the high-risk patients showed sensitive responses to five chemotherapy drugs. Finally, 10 candidate small-molecule drugs for CESC were defined. In summary, the CD1C-CD6 signature can accurately predict the prognosis of CESC. 相似文献
6.
《Annales de cardiologie et d'angeiologie》2015,64(3):169-174
AimsTo study the influence of postural changes on aldosterone to renin ratio (ARR) in patients with suspected secondary hypertension and to evaluate the sensitivity and specificity of the recommended seated ARR compared to supine and upright ARR for primary aldosteronism screening.MethodsFifty-three hypertensive patients were prospectively hospitalized for secondary hypertension exploration (age: 51 ± 12, 66% males). After withdrawal of drugs interfering with renin angiotensin system, plasma aldosterone and direct renin concentration were measured in the morning, at bed after an overnight supine position, then out of bed after 1 hour of upright position and finally 2 hours later after 15 minutes of seating. Minimal renin value was set at 5 μUI/mL.ResultsReferring to ARR cut-off of 23 pg/μUI, the sensitivity of seated ARR was 57.1% and specificity was 92.3%. The negative and positive predictive values were 95.1% and 45.2% respectively. Compared to these results, a cut-off of 19 improved sensitivity to 85.7% with a specificity of 89.7%. Negative and positive predictive values were 98.3% and 41.1% respectively. Seated ARR mean value was lower than supine and upright ARR mean values, due to an overall increase in renin at seating compared to the supine position by factor 1.9 while aldosterone just slightly increased by factor 1.2. Seated ARR correlated to supine and upright ARR: correlation coefficients (r) 0.90 and 0.93 respectively (P < 0.001).ConclusionsCurrent recommended measurement of ARR in the seating position is fairly correlated to supine and upright ARR. A suggested cut-off value of 19 instead of 23 pg/μUI increased the discriminating power of this test. 相似文献
7.
Waseem Raza Hafiza Anum Mohy-u-Din Sajid Shaeen Malik Iqra Manzoor Baby Nadeem 《Ultrasound in medicine & biology》2019,45(1):21-25
The objective of the study was to evaluate the reliability of sonoelastography in ductal carcinoma in patients in primary and secondary health care settings. Google Scholar, PubMed, Medline, Medscape, Wikipedia and NCBI were searched in January 2018 for all original research and review articles to identify relevant studies. Two reviewers selected the articles independently for based on the title and abstract. The selection criteria were sonoelastography accuracy for diagnosing ductal carcinoma as index text, B-mode sonography, and micropure imaging; surgery and histologic findings were used as reference text; and benign and malignant breast abnormalities and ductal carcinoma were used as target conditions. Two reviewers extracted the data on selected study characteristics, and the results were used to construct the tables and figures. Fifteen studies on ductal carcinoma were found. The overall sensitivity of sonoelastography in diagnosing ductal carcinoma was 85.7%, and the specificity, 79.8%. On the basis of the literature review, it was concluded that sonoelastography has high sensitivity and specificity in diagnosing ductal carcinoma. 相似文献
8.
9.
Watanachai Klankluang Panate Pukrittayakamee Wanlop Atsariyasing Arunotai Siriussawakul Pratamaporn Chanthong Sasima Tongsai Supakarn Tayjasanant 《The oncologist》2020,25(2):e335-e340
Background
Delirium, a neuropsychiatric syndrome that occurs throughout medical illness trajectories, is frequently misdiagnosed. The Memorial Delirium Assessment Scale (MDAS) is a commonly used tool in palliative care (PC) settings. Our objective was to establish and validate the Memorial Delirium Assessment Scale-Thai version (MDAS-T) in PC patients.Materials and Methods
The MDAS was translated into Thai. Content validity, inter-rater reliability, and internal consistency were explored. The construct validity of the MDAS-T was analyzed using exploratory factor analysis. Instrument testing of the MDAS-T, the Thai version of the Confusion Assessment Method for the Intensive Care Unit (CAM-ICU-T), and the Diagnostic and Statistical Manual of Mental Disorders, Fifth Edition as the gold standard was performed. The receiver operating characteristic (ROC) curve was used to determine the optimal cutoff score. The duration of each assessment was recorded.Results
The study enrolled 194 patients. The content validity index was 0.97. The intraclass correlation coefficient and Cronbach's α coefficient were 0.98 and 0.96, respectively. A principal component analysis indicated a homogeneous, one-factor structure. The area under the ROC curve was 0.96 (95% confidence interval [CI], 0.93–0.99). The best combination of sensitivity and specificity (95% CI) of the MDAS-T were 0.92 (0.85–0.96) and 0.90 (0.82–0.94), respectively, with a cutoff score of 9, whereas the CAM-ICU-T yielded 0.58 (0.48–0.67) and 0.98 (0.93–0.99), respectively. The median MDAS-T assessment time was 5 minutes.Conclusion
This study established and validated the MDAS-T as a good and feasible tool for delirium screening and severity rating in PC settings.Implications for Practice
Delirium is prevalent in palliative care (PC) settings and causes distress to patients and families, thereby making delirium screening necessary. This study found that the MDAS-T is a highly objective and feasible test for delirium screening and severity monitoring in PC settings and can greatly improve the quality of care for this population.10.
《The ocular surface》2020,18(1):108-113
PurposeAromatase inhibitors (AIs) limit the synthesis of oestrogen in peripheral tissues thus lowering levels of oestrogen. The primary aim was to evaluate whether women treated with AIs have altered dry eye symptoms and signs. A sub-aim was to investigate whether symptoms of dry eye in postmenopausal women were associated with symptoms of non-eye pain, ocular pain and self-rated pain perception.MethodsThis cross-sectional, observational, single visit study recruited 56 postmenopausal women (mean age 64.1 + 7.9 years) and 52 undergoing AI treatment (mean age 66.6 + 9.0). Ocular symptoms (OSDI, MGD14) and pain questionnaires (PSQ, OPAS) were administered and signs of dry eye and meibomian gland dysfunction were evaluated.ResultsAlmost half of each group reported dry eye symptoms, defined as OSDI>12 (48% control, 46% AI). The PSQ score was significantly higher in the AI group (p = 0.04). Neither frequency or severity of dry eye (or MGD) symptoms scores were significantly different between groups. In the AI group, meibomian gland expressibility score was worse (p = 0.003); there were no differences in any other signs. Higher OSDI scores were associated with higher OPAS eye-pain scores (r = 0.49, p < 0.001), but not OPAS non-eye pain (r = 0.09, p = 0.35). Pain perception (PSQ) showed a moderate positive association with OPAS eye-pain (r = 0.30, p = 0.003).ConclusionsIn this study elevated ocular symptoms were observed in both the AI treated and the untreated groups, with no difference between the groups. Women undergoing AI treatment for early stage breast cancer had worse meibum expressibility score and increased pain perception compared to an untreated group of women. 相似文献