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81.
Introduction: We hypothesized that pleocytosis, which is a marker of central nervous system (CNS) inflammation, would result in viral genetic equilibration or de-compartmentalization between HIV populations in the blood and cerebrospinal fluid (CSF), suggesting viral trafficking.Methods: Study subjects, who started or interrupted their antiretroviral treatment, had viral loads measured and clonal viral env sequences generated from HIV RNA extracted from paired blood and CSF samples. White blood counts in CSF were also measured at each timepoint. Degree of inter-compartment segregation was calculated by posterior probability using linear discriminant analysis and multidimensional scaling. Co-receptor usage was determined using a trained support vector machine.Results: Pleocytosis was strongly associated with disruption of viral compartmentalization.Conclusions: Inflammation in the CNS, marked by pleocytosis, allows HIV populations to mix between blood and CSF, which may increase the overall viral genetic diversity within the CSF.  相似文献   
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84.

Background:

Stroke in the young is particularly tragic because of its potential to create a long-term burden on the victims, their families, and the community. There had been relatively few studies on young stroke in Kerala''s socio-economic setup, that too encapsulating the mentioned apparently relevant dimensions of stroke in the young.

Objective:

To study the prevalence, patterns and risk factors of young stroke.

Settings and Design:

A cross-sectional study with case control comparison at Government Medical College Hospital, Thiruvananthapuram, Kerala, India.

Materials and and Methods:

Total 100 stroke patients were identified over a period of 2 months, and data were collected on the basis of questionnaire developed for the purpose.

Results:

Of 100 stroke patients, 15 had stroke in the young, among which 9 (60%) had ishaemic stroke. Hypertension was the most common risk factor. Smoking, alcohol, atrial fibrillation, and hyperlipidemia were found to be more common in cases (young stroke) when compared with controls. Alcohol use and atrial fibrillation were significantly higher among young stroke patients. Physical inactivity was significantly lesser in those with stroke in the young than elderly. Atrial fibrillation emerged as an independent risk factor of stroke in the young with adjusted odds ratio of 6.18 (1.31-29.21).

Conclusion:

In all, 15% of total stroke occurred in young adults <50 years. The proportion of hemorrhagic stroke in young adults is higher than in elderly. Atrial fibrillation is identified as an independent risk factor of stroke in the young. Compared with stroke in elderly alcohol use, smoking, hyperlipidemia, and cardiac diseases, which are known risk factors, are higher in young stroke.  相似文献   
85.
Serotonin 1A (5‐HT1A) receptors play a direct role in neuronal development, cell proliferation, and dendritic branching. We hypothesized that variability in 5‐HT1A binding can affect cortical thickness, and may account for a subtype of major depressive disorder (MDD) in which both are altered. To evaluate this, we measured cortical thickness from structural magnetic resonance imaging (MRI) and 5‐HT1A binding by positron emission tomography (PET) in an exploratory study. To examine a range of 5‐HT1A binding and cortical thickness values, we recruited 25 healthy controls and 19 patients with MDD. We hypothesized increased 5‐HT1A binding in the raphe nucleus (RN) would be negatively associated with cortical thickness due to reduced serotonergic transmission. Contrary to our hypothesis, raphe 5‐HT1A binding was positively correlated with cortical thickness in right posterior cingulate cortex (PCC), a region implicated in the default mode network. Cortical thickness was also positively correlated with 5‐HT1A in each cortical region. We further hypothesized that the strength of 5‐HT1A‐cortical thickness correlation depends on the number of axons between the raphe nucleus and each region. To explore this we related 5‐HT1A–cortical thickness correlation coefficients to the number of tracts connecting that region and the raphe, as measured by diffusion tensor imaging (DTI) in an independent sample. The 5‐HT1A–cortical thickness association correlated significantly with the number of tracts to each region, supporting our hypothesis. We posit a defect in the raphe may affect the PCC within the default mode network in MDD through serotonergic fibers, resulting in increased ruminative processing.  相似文献   
86.
Accurate recognition of movement disorder phenomenology may differentiate children with anti‐N‐methyl D‐aspartate receptor (NMDAR) encephalitis, autoimmune basal ganglia encephalitis (BGE), and Sydenham's chorea (SC). Three neurologists blinded to the diagnoses recorded dominant and associated movement disorders seen on videos of 31 patients with anti‐NMDAR encephalitis (n = 10), BGE (n = 12), and SC (n = 9). Stereotypy was only seen in anti‐NMDAR encephalitis (8/10) and not in BGE and SC (P < 0.001). Perseveration was only seen in anti‐NMDAR encephalitis (5/10) and not in BGE and SC (P < 0.001). Akinesia was more commonly seen in BGE (5/12) than in anti‐NMDAR encephalitis (1/10, P = 0.097). Tremor was more commonly seen in BGE (5/12) than in anti‐NMDAR encephalitis (1/10, P = 0.097). Chorea was seen in all groups: anti‐NMDAR encephalitis (4/10), BGE (3/12), and SC (9/9). Likewise, dystonia was seen in all groups: anti‐NMDAR encephalitis (6/10), BGE (7/12), and SC (2/9). Stereotypies or perseveration are suggestive of anti‐NMDAR encephalitis, whereas their absence and the presence of akinesia and tremor is more suggestive of BGE. Chorea and dystonia are least discriminating. © 2014 International Parkinson and Movement Disorder Society  相似文献   
87.
Infusions of large numbers (> 10(8)/kg) of donor leukocytes can induce remissions in patients with chronic myeloid leukemia (CML) who relapse after marrow transplantation. We wanted to determine if substantially lower numbers of donor leukocytes could induce remissions and, if so, whether this would reduce the 90% incidence of graft-versus-host disease (GVHD) associated with this therapy. Twenty-two patients with relapsed CML were studied: 2 in molecular relapse, 6 in cytogenetic relapse, 10 in chronic phase, and 4 in accelerated phase. Each patient received escalating doses of donor leukocytes at 4- to 33-week intervals. Leukocyte doses were calculated as T cells per kilogram of recipient weight. There were 8 dose levels between 1 x 10(5) and 5 x 10(8). Lineage-specific chimerism and residual leukemia detection were assessed using sensitive polymerase chain reaction (PCR) methodologies. Nineteen of the 22 patients achieved remission. Remissions were achieved at the following T-cell doses: 1 x 10(7) (n = 8), 5 x 10(7) (n = 4), 1 x 10(8) (n = 3), and 5 x 10(8) (n = 4). To date, 15 of the 17 evaluable patients have become BCR-ABL negative by PCR. The incidence of GVHD was correlated with the dose of T cells administered. Only 1 of the 8 patients who achieved remission at a T-cell dose of 1 x 10(7)/kg developed GVHD, whereas this complication developed in 8 of the 11 responders who received a T-cell dose of > or = 5 x 10(7)/kg. Three patients died in remission, 1 secondary to marrow aplasia, 1 of respiratory failure and 1 of complications of chronic GVHD. Sixteen patients who were mixed T-cell chimeras before treatment became full donor T-cell chimeras at the time of remission. Donor leukocytes with a T-cell content as low as 1 x 10(7)/kg can result in complete donor chimerism together with a potent graft-versus-leukemia (GVL) effect. The dose of donor leukocytes or T cells used may be important in determining both the GVL response and the incidence of GVHD. In many patients, this potent GVL effect can occur in the absence of clinical GVHD.  相似文献   
88.

Aim

Mild traumatic brain injury (MTBI) is associated with often selective impairment of both working memory (WM) and the executive functions (EFs). Research indicates that one of the commonest deficits present in MTBI patients falls in the domain of WM. We aimed to investigate the role of EFs in WM impairment following MTBI.

Methods

Performance on the tests of EFs and the verbal and visuo-spatial WM of 30 consecutive MTBI patients were compared with age/education/IQ matched 30 normal healthy control participants. Correlation between EFs and WM was studied separately for the MTBI and the control group.

Results

The MTBI and control group were tested on a range of EF tests and WM. The MTBI group was demonstrated impairment on verbal and visuo-spatial WM and category fluency tests only. Furthermore, the MTBI group had fewer significant correlations between the WM and EFs (5 out of 54 possible correlations) than in the control group (13 out of 54 possible correlations).

Conclusions

We suggest that MTBI may lead to WM deficits as the contribution of executive processes to support the WM is diminished following MTBI. Such an understanding of the poor WM performance in MTBI patients will be helpful when planning appropriate strategies for cognitive rehabilitation.  相似文献   
89.
BACKGROUND: Cerebral perfusion pressure management (CPPM) is an accepted modality of treatment of severe diffuse head injury (SDHI). However, CPPM has the potential to cause transcapillary exudation in the presence of a disrupted blood brain barrier and can lead to further increase of intracranial pressure (ICP) and worsening of compliance. AIMS: This study attempts to evaluate the effect of both transient and prolonged changes in cerebral perfusion pressure (CPP) on ICP and cerebral compliance as measured by the Pressure Volume Index (PVI), and to correlate changes in PVI with outcome at 12 months using the Glasgow Outcome Score. SETTINGS AND DESIGN: Prospective study in a neurosurgical ICU. MATERIAL AND METHODS: Twenty-seven SDHI patients managed using standard protocol to maintain CPP above 70 mmHg. Mean arterial pressure (MAP), ICP and CPP were monitored every half-hour. Daily monitoring of the PVI and ICP was done before, and after the induced elevation of MAP using IV Dopamine infusion. The relationship between CPP, MAP, ICP, PVI and outcome was evaluated. STATISTICAL ANALYSIS USED: The paired and independent samples T-test, and the Pearson correlation coefficient. RESULTS: CPPM rarely leads to progressive rise in ICP. Maintaining CPP above 70mmHg does not influence ICP or PVI. Transient elevations in CPP above 70mmHg may produce a small rise in ICP. Trend of change in PVI influenced outcome despite similar ICP and CPP. CONCLUSION: Elevating the CPP above 70mmHg does not either reduce the ICP or worsen the compliance. Monitoring changes in compliance should form an integral part of CPPM.  相似文献   
90.
Scott  MD; Eaton  JW; Kuypers  FA; Chiu  DT; Lubin  BH 《Blood》1989,74(7):2542-2549
To delineate further the role of superoxide dismutase (SOD) in red blood cell (RBC) oxidant defense, normal human erythrocytes were osmotically lysed and resealed in the presence of varying concentrations of exogenous SOD. This resulted in a dose-dependent increase in SOD activity in the resealed erythrocytes while maintaining nearly normal RBC hemoglobin concentration (less than 10% decrease from the control value), cell volume, and cellular deformability. Surprisingly, a five- or ninefold increase in SOD activity yielded no additional protection against superoxide-generating drugs (phenazine methosulfate or menadione sodium bisulfite). No significant differences were observed between the control and SOD-loaded RBCs in O2-driven methemoglobin formation or generation of thiobarbituric acid-reactive substances. In contrast, RBCs with elevated SOD activity pretreated with sodium azide (to block catalase activity) or 1-chloro-2,4- dinitrobenzene (to deplete reduced glutathione, GSH) showed significantly enhanced methemoglobin generation in response to superoxide generating drugs. No differential response was noted between the control, control-resealed, and SOD-loaded RBCs to oxidants other than superoxide. Based on our results and other data, we conclude that elevated SOD activity may imbalance cellular oxidant defense, resulting in enhanced oxidation due to the accelerated generation of H2O2, the product of O2- dismutation. This effect is significantly exacerbated under conditions in which H2O2 catabolism is altered.  相似文献   
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