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61.
People living with HIV (PLWH) age with an excess burden of comorbidities that may increase the incidence of age-related complications. There is controversy surrounding the hypothesis that HIV can accelerate neurodegeneration and Alzheimer’s dementia (AD). We performed a retrospective study to analyze the distribution of cerebrospinal fluid (CSF) AD biomarkers (beta amyloid 1–42 fragment, tau, and phosphorylated tau) in adult PLWH (on cART with undetectable viremia, n = 136, with detectable viremia, n = 121, and with central nervous system CNS disorders regardless of viremia, n = 72) who underwent a lumbar puncture between 2008 to 2018; HIV-negative controls with AD were included (n = 84). Five subjects (1.5%) presented CSF biomarkers that were compatible with AD: one was diagnosed with AD, whereas the others showed HIV encephalitis, multiple sclerosis, cryptococcal meningitis, and neurotoxoplasmosis. Regardless of confounders, 79.6% of study participants presented normal CSF AD biomarkers. Isolated abnormalities in CSF beta amyloid 1–42 (7.9%) and tau (10.9%) were associated with age, biomarkers of intrathecal injury, and inflammation, although no HIV-specific feature was associated with abnormal CSF patterns. CSF levels of AD biomarkers very poorly overlapped between HIV-positive clinical categories and AD controls. Despite the correlations with neurocognitive performance, the inter-relationship between amyloid and tau proteins in PLWH seem to differ from that observed in AD subjects; the main driver of the isolated increase in tau seems represented by non-specific CNS inflammation, whereas the mechanisms underlying isolated amyloid consumption remain unclear.  相似文献   
62.
Discussed the utility of a measure of aggression using the MMPI (N = 54). Although child abusers significantly differed from a distressed and socioeconomic-status matched group on this scale, a discriminative analysis on the scale failed to adequately differentiate the groups. Results are discussed in terms of the deficiences in the current method of separating their groups and for constructing measures that are likely to differentiate aggressive from nonaggressive populations.  相似文献   
63.
Venous ulcers are common, especially in the elderly, accounting for more than 50% of all lower extremity ulcers with important socioeconomic problems. Improving extracellular matrix functioning, by heparin administration, seems to be a way to support wound healing. A total of 284 patients with venous ulcers were recruited in a 4‐year period. All patients were subjected to the most appropriate treatment after considering their preference (compression therapy followed or not by vein surgery). Patients were randomised into two groups of 142 persons in each (group A and group B as cases and controls, respectively). Patients of group A, in addition to the basic treatment as described earlier, received administration of nadroparin 2850 IU/0.3 ml through subcutaneous injection once a day for 12 months, whereas group B patients received basic treatment alone. Healing was assessed by means of direct ulcer tracing with computerised planimetry. Group A showed a healing rate of 83·80% at 12 months, whereas that of group B was 60·56%. Results by age group surprisingly showed that the group of older patients took the most advantage from long‐term treatment with low molecular weight heparin; this group also had lowest recurrence rate.  相似文献   
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Purpose To evaluate the circadian effects on intraocular pressure (IOP) and ocular perfusion pressure (OPP) of 0.5% timolol or 0.005% latanoprost in Caucasian patients affected by normal-tension glaucoma (NTG). Patients and methods In this crossover trial, 30 consecutive NTG subjects underwent three 24-hour assessments of IOP, blood pressure (BP), heart rate (HR), and OPP [calculated according to the formula OPP = (1/3 systolic BP + 2/3 diastolic BP) x 2/3 – IOP]: at baseline, and after 1-month treatment with timolol or latanoprost. These parameters were recorded at 4 a.m., 8 a.m., noon, 4 p.m., 8 p.m., and midnight. Results Both timolol and latanoprost reduced IOP (p < 0.001), with a difference in favour of latanoprost of 1.3 mmHg (95% CI 0.9, 1.6; p < 0.001). After timolol, BP and HR decreased with respect to baseline (p < 0.001). Latanoprost increased mean OPP (3.6 mmHg, 95% CI 2.9, 4.3; p < 0.001), whereas timolol did not improve it. Conclusions Latanoprost induces an IOP reduction greater than timolol, also achieving a better circadian flattening of the IOP curve. Only latanoprost significantly increased mean 24-hour OPP. The management of Caucasian NTG patients should be critically realized, considering the 24-hour influence of each IOP-lowering drug on the ocular blood perfusion.  相似文献   
66.
PURPOSE: To report a mesectodermal leiomyoma of the posterior choroid. DESIGN: Observational case report. METHODS: A 23-year-old man was referred to us because of a progressive blurred vision in his left eye. Ophthalmologic examination revealed the presence of a 12 x 10 x 7.2-mm amelanotic choroidal mass in his left posterior pole. Fluorescein angiography, A-scan ultrasonography, and B-scan echography findings were suggestive for a diagnosis of choroidal amelanotic melanoma. These clinical features prompted us to enucleate the left eye. RESULTS: Histopathological and immunohistochemistry examinations established a definitive diagnosis of mesectodermal leiomyoma of the posterior choroid. CONCLUSION: This case represents the first report describing the occurrence of an intraocular mesectodermal leiomyoma that may exclusively involve the posterior choroid.  相似文献   
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68.
BACKGROUND: The urea breath test is routinely used for diagnosing or confirming the eradication of Helicobacter pylori. AIM: To evaluate the appropriateness of urea breath test referrals. METHODS: The age, sex, symptoms, endoscopic findings, use of non-steroidal anti-inflammatory drugs, family history of gastric cancer or H. pylori infection and concomitant diseases of patients referred for urea breath testing in a 1-year period were recorded. The appropriateness of urea breath test referrals was judged according to Maastricht guidelines. RESULTS: One thousand, three hundred and twenty subjects (47 +/- 16 years) were referred in 2001: 578 (43.8%) for the diagnosis and 742 (56.2%) for confirmation of the eradication of H. pylori. The urea breath test was considered to be appropriate in 836 (63.3%) patients, inappropriate in 192 (14.5%) and appropriate but avoidable in 292 (22.1%). The appropriateness ratios of urea breath test referrals were 4.6 and 9.0 (P < 0.0001) for general practitioners and gastroenterologists, respectively. Of the patients (n=230) with un investigated dyspepsia, who underwent urea breath testing according to a 'test and treat' strategy, 98 (42.6%) presented at least one risk factor for organic disease. CONCLUSIONS: In Italy, nearly 36% of urea breath test referrals are inappropriate or could be avoided if all dyspeptic patients with risk factors were referred for endoscopy or all dyspeptic patients undergoing endoscopy were tested for H. pylori infection with biopsy methods. Both general practitioners and, to a lesser extent, gastroenterologists require educational programmes to deal effectively with H. pylori.  相似文献   
69.
AIMS: To measure the unbound plasma concentrations of saquinavir (SQV) and indinavir (IDV) and to relate them to the total plasma concentrations in order to establish the unbound percentage of protease inhibitors in vivo during a full dosage interval profile. METHODS: HIV-infected subjects (n = 35; median CD4 cell count = 340 x 10(6) cells l-1, range: 120-825; viral load < 50 copies ml-1 in 22/35) treated with SQV or IDV containing regimens were studied. Plasma drug samples were collected at 0, 2, 4, 8 and 12 h postdose for the twice daily regimens and 0, 1, 2, 4 and 8 h for the three times daily regimens. Ultra-filtration was used to separate unbound IDV and SQV in plasma and their respective concentrations were measured by a fully validated method using high performance liquid chromatography-mass spectometry (h.p.l.c.-MS/MS). RESULTS: Based on the ratio AUCunbound/AUCtotal, the median unbound percentage (95% CI for differences) of SQV and IDV from all the samples studied was 1.19% (0.99, 1.58%) and 36.3% (35.1, 44.2%), respectively. No significant difference was seen in the percentage binding of SQV between patients receiving SQV alone (median = 1.49%) or with ritonavir (median = 1.09%; P = 0.141; 95% CI for difference between medians = -0.145, 0.937) over the pharmacokinetic profile. Similarly, no significant difference was seen in the percentage binding of IDV in patients receiving IDV alone (median 35.2%) or with ritonavir (median = 41.3%; P = 0.069; 95% CI for difference between medians = -0.09, 15.4). The unbound concentrations of SQV (P < 0.0001; 95% CI for r(2) = 0.634, 0.815) and IDV (P < 0.0001; 95% CI for r(2) = 0.830, 0.925) remained constant as a proportion of total concentration over the full dosing profile. CONCLUSIONS: These in vivo data confirm previously published in vitro measurements of SQV and IDV protein binding. The unbound percentage of both protease inhibitors remained constant over the dosing interval.  相似文献   
70.
The case is described of a patient who, following cerebral hypoxia, developed severe difficulty in orienting himself in new environments in the context of a mild global amnesic syndrome. Some episodes he related suggested that his main difficulty was remembering the spatial/directional value of landmarks he recognised. A neuroradiological examination documented severe bilateral atrophy of the hippocampi associated with atrophic changes in the cerebral hemispheres, most marked in the dorsal regions. Neuropsychological and experimental evaluation showed a severe deficit of spatial learning with substantially preserved ability to learn verbal and visual-object information. He was also virtually unable to learn a route in a maze task based exclusively on spatial data, but the availability of visual cues substantially improved his learning. Finally, he performed within normal limits on various tests investigating knowledge acquired premorbidly regarding famous buildings, routes in the town he had been living in since childhood, and geography. Topographical disorientation may be subtended by a specific difficulty in storing the spatial/directional value of visual landmarks in novel environments. The hippocampus appears to be involved in the acquisition of new topographical spatial knowledge.  相似文献   
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