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51.
A strategy for the isolation of mononuclear cells from the brain parenchyma of mice with ongoing central nervous system (CNS) inflammation has been developed in order to permit flow cytometric (FCM) analysis of these cell populations. Sindbis virus (SV) encephalitis in mice is characterized morphologically by an infiltration of mononuclear cells into both brain parenchyma and cerebrospinal fluid (CSF). Perfused brain tissue from infected animals is collected, homogenized, and subjected to a mild enzymatic digestion. A sedimentation at unit gravity is performed to remove any large particulate debris, and the remaining tissue is then centrifuged over a modified density gradient which separates intact cells from smaller tissue fragments. Cells collected directly from these gradients can be stained with monoclonal antibodies and analyzed by FCM without further manipulation. Data generated by this method correlates with previous studies of SV encephalitis using immunohistochemical analysis of brain tissue sections to quantify mononuclear cell types. This suggests that representative samples of the cellular infiltrate are obtained using this technique. The approach however, offers the possibility of more sophisticated and quantitative analyses of CNS inflammatory cells which is unobtainable by tissue section staining.  相似文献   
52.
Hereditary canine spinal muscular atrophy (HCSMA) is a dominantly inherited motor neuron disease that produces muscle weakness and atrophy. Immunocytochemical and computer-imaging morphometric methods were used to compare early changes that occurred in dogs with HCSMA (n = 4) versus controls (n = 2). The size and number of neurons in the ventral horn and the number of motor neurons expressing choline acetyltransferase were quantitated. The density of all ventral horn neurons per micrometer squared in dogs with HCSMA was greater than controls, and there were more small neurons than in controls. Immunocytochemical methods revealed more small cholinergic neurons and fewer large cholinergic neurons in HCSMA than in controls, suggesting growth arrest in HCSMA or a shift in size class from large cholinergic neurons to small ones. The density of cholinergic neurons per micrometer squared was not significantly different between the two groups. Analysis of predicted distributions of cholinergic and noncholinergic neurons revealed that HCSMA cholinergic neurons were smaller and that, in some size classes, fewer neurons expressed choline acetyltransferase. These observations indicate that in HCSMA the motor neuron fails to achieve normal size and/or undergoes atrophy.  相似文献   
53.
A minority of patients with hereditary angioedema (HAE) have normal concentrations of a dysfunctional C1 inhibitor protein (C1INH) in their plasmas. We purified C1INH from the plasmas of one such patient before and during treatment with the anabolic steroid stanozolol. Both the pretreatment plasma and plasma obtained during stanozolol treatment contained varying amounts of two extremely similar C1INH proteins that were functionally distinct. The pretreatment plasma contained primarily (94%) dysfunctional C1INH that did not inactivate or complex with either purified C1s, activated Hageman factor, or kallikrein and small amounts (6%) of functionally normal C1INH. Stanozolol treatment increased the plasma concentrations of both of these proteins as well as the proportion (23%) of functional C1INH in the plasma. The purified dysfunctional and functional C1INHs had identical or nearly identical molecular sizes, charges, amino acid compositions, and amino sugar contents, and could not be distinguished physicochemically from each other or from normal C1INH. From these studies of purified C1INH proteins we concluded that HAE associated with dysfunctional C1INH is due to a defect at the structural locus for one C1INH gene and that both the dysfunctional C1INH gene and the normal C1INH gene products are present in the plasma of the affected subject. Treatment with stanozolol comparably increased the synthesis of both C1INH proteins. The disproportionate rise in the level of the normal C1INH protein is consistent with the view that it is more rapidly catabolized as a consequence of its interaction with the proteases it inactivates.  相似文献   
54.
Jejunal biopsy specimens from 20 human immunodeficiency virus (HIV) positive male homosexual patients were analysed and compared with those of a control group to determine whether the abnormalities were caused by the virus or by opportunistic infection. The degree of villous atrophy was estimated with a Weibel eyepiece graticule, and this correlated strongly with the degree of crypt hyperplasia, which was assessed by deriving the mean number of enterocytes in the crypts. The density of villous intraepithelial lymphocytes fell largely within the normal range, either when expressed in relation to the number of villous enterocytes or in relation to the length of muscularis mucosae. Villous enterocytes showed mild non-specific abnormalities. Pathogens were sought in biopsy sections and in faeces. Crypt hyperplastic villous atrophy occurred at all clinical stages of HIV disease and in the absence of detectable enteropathogens. An analogy was drawn between HIV enteropathy and the small bowel changes seen in experimental graft-versus-host disease. It is suggested that the pathogenesis of villous atrophy is similar in the two states, the damage to the jejunal mucosa in HIV enteropathy being inflicted by an immune reaction mounted in the lamina propria against cells infected with HIV.  相似文献   
55.
The visna viruses are antigenically related nononcogenic retroviruses of sheep. The original strain was isolated from the brain of a paralyzed sheep in Iceland during the 1940s. The prototype strains has been passed serially in sheep and has undergone progressive antigenic change. Previous reports have shown that such antigenic changes in visna virus can be reproduced in infected cell cultures treated with neutralizing antibody. We now show that the antigenic profiles of the emerging mutants directly reflect the nature of the selecting antibody. Mutants with minor antigenic changes were selected by "early" sera which had a limited neutralization range. Mutants with greater antigenic changes were selected by "late" sera with a wide neutralization range. Mutants selected by early sera emerged rapidly and consistently in cultures, and these were antigenically very similar to one another. Mutants rarely emerged in cultures treated with late sera, but these viruses showed major antigenic changes. The data suggest that the evolution of antigenic mutants of visna virus progresses by a series of minor mutations which accumulate under the selective pressure of antibody.  相似文献   
56.
Between June 1977 and April 1983, the Radiation Therapy Oncology Group (RTOG) sponsored a Phase III randomized study investigating fast neutron radiation therapy in the treatment of patients with locally advanced (Stage C and D1) adenocarcinoma of the prostate gland. Patients were randomized to receive either conventional photon radiation therapy or fast neutron irradiation used in a mixed-beam treatment schedule (neutron/photon). A total of 91 analyzable patients were entered in the study; 78 of them were treated without major protocol deviations. The two treatment groups were balanced in regard to all major prognostic variables. Actuarial curves for "overall" survival, "determinantal" survival and local/regional control are presented both for the entire group of 91 patients and the 78 patients treated within protocol guidelines. The overall local/regional tumor recurrence rate is 7% for the mixed-beam treated group of patients and is 22% for the photon (X ray) treated group of patients. The difference is statistically significant at the p = 0.05 level. For the entire group of 91 evaluable patients, the 5-year "overall" survival rate is 62% for the mixed-beam-treated group and 35% for the photon-treated group. This difference is also statistically significant (p less than 0.05). However, this statistical significance is lost when the smaller number of patients treated strictly within protocol guidelines is considered. The significance is regained (p less than 0.02) when one looks at "determinantal" survival, which uses active cancer at time of death as the failure endpoint. This study demonstrates that a regional treatment modality, in this case mixed-beam irradiation, can influence both local/regional tumor control and survival in patients with locally-advanced adenocarcinoma of the prostate gland.  相似文献   
57.
Ageing is associated with postprandial muscle vascular and metabolic dysfunction, suggesting vascular modifying interventions may be of benefit. Reflecting this, we investigated the impact of acute cocoa flavanol (450–500 mg) intake (versus placebo control) on vascular (via ultrasound) and glucose/insulin metabolic responses (via arterialised/venous blood samples and ELISA) to an oral nutritional supplement (ONS) in twelve healthy older adults (50% male, 72 ± 4 years), in a crossover design study. The cocoa condition displayed significant increases in m. vastus lateralis microvascular blood volume (MBV) in response to feeding at 180 and 240-min after ONS consumption (baseline: 1.00 vs. 180 min: 1.09 ± 0.03, p = 0.05; 240 min: 1.13 ± 0.04, p = 0.002), with MBV at these timepoints significantly higher than in the control condition (p < 0.05). In addition, there was a trend (p = 0.058) for MBV in m. tibialis anterior to increase in response to ONS in the cocoa condition only. Leg blood flow and vascular conductance increased, and vascular resistance decreased in response to ONS (p < 0.05), but these responses were not different between conditions (p > 0.05). Similarly, glucose uptake and insulin increased in response to ONS (p < 0.05) comparably between conditions (p > 0.05). Thus, acute cocoa flavanol supplementation can potentiate oral feeding-induced increases in MBV in older adults, but this improvement does not relay to muscle glucose uptake.  相似文献   
58.
Foodborne illness source attribution is foundational to a risk-based food safety system. We describe a method for attributing US foodborne illnesses caused by nontyphoidal Salmonella enterica, Escherichia coli O157, Listeria monocytogenes, and Campylobacter to 17 food categories using statistical modeling of outbreak data. This method adjusts for epidemiologic factors associated with outbreak size, down-weights older outbreaks, and estimates credibility intervals. On the basis of 952 reported outbreaks and 32,802 illnesses during 1998–2012, we attribute 77% of foodborne Salmonella illnesses to 7 food categories (seeded vegetables, eggs, chicken, other produce, pork, beef, and fruits), 82% of E. coli O157 illnesses to beef and vegetable row crops, 81% of L. monocytogenes illnesses to fruits and dairy, and 74% of Campylobacter illnesses to dairy and chicken. However, because Campylobacter outbreaks probably overrepresent dairy as a source of nonoutbreak campylobacteriosis, we caution against using these Campylobacter attribution estimates without further adjustment.  相似文献   
59.
Neurosurgical Review - Unruptured intracranial saccular aneurysms occur in 3–5% of the general population. As the use of diagnostic medical imaging has steadily increased over the past few...  相似文献   
60.
BackgroundThe surgical treatment of moderate-advanced hallux rigidus is controversial. Cheilectomy is widely used but has recurrence rates of up to 30%. Dorsal oblique metatarsal osteotomy (DOO) has also shown good results, however, there is no study comparing outcomes of the DOO against cheilectomy.MethodsThis was a retrospective propensity score matched study based on registry data from a single tertiary institution. Between 2007 and 2017, all patients who had undergone dorsal cheilectomy or DOO for hallux rigidus were included. Patients with previous foot surgery, revision surgeries, and concomitant surgical procedures were excluded. Clinical outcomes, complication rates, revision rates and patient satisfaction were assessed at 2 years postoperatively.ResultsThere were 44 patients (34 cheilectomy, 10 DOO). After propensity score matching, 17 cheilectomy and all 10 DOO cases were selected for comparison. Patients in both groups had a significant improvement in visual analogue pain scores (VAS) and AOFAS 1st toe scores 2-years post-operatively (P < 0.001) with high levels of post-operative satisfaction (85.1%). Overall there were no statistically significant differences in post-operative scores, improvement in scores, complication rates, revision rates, and levels of patient satisfaction between groups.ConclusionsBoth the DOO and cheilectomy give similarly good outcomes for moderate-advanced hallux rigidus. Further studies are needed to elucidate differences in indications for each procedure.  相似文献   
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