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1.
In six experiments the course of a Trichinella spiralis infection in congenitally athymic (nu/nu) mice and their heterozygous thymus-bearing littermates (+/nu) was followed. In the +/nu mice worms were expelled at day 10 post infection. In nu/nu mice worms remained in the intestine until the end of the observation period (83 days post infection). In testing the yield of muscle larvae in +/nu and nu/nu mice 4--5 times more muscle larvae were isolated from nu/nu mice than from infected +/nu mice. The following phenomena were observed in +/nu mice only: anti-T. spiralis antibodies detected by immunofluorescence, intestinal plasma-cell production and intestinal eosinophilia. In nu/nu mice no blood eosinophilia was observed in contrast to the induction of eosinophilia both in infected +/nu and infected nu/nu mice reconstituted with thymuses from heterozygous littermates. Intra-epithelial lymphocytes, more numerous in +/nu than in nu/nu mice, were not attracted by Trichinella antigen. The data supported the hypothesis that worm expulsion is a T cell-dependent phenomenon. Plasma cell and antibody production as well as tissue and blood eosinophilia were shown to be thymus-dependent in a T. spiralis infection.  相似文献   
2.
Bone marrow examinations were performed on 20 patients with acquired immune deficiency syndrome (AIDS) and 39 with AIDS-related complex (ARC). Fever of unknown origin and thrombocytopenia were common in ARC, but anemia and leukopenia were most frequent in AIDS. Changes in stromal cells and perivascular cuffing of plasma cells were found significantly more often in patients with AIDS than in those with ARC. Malignancies were common in both groups. Human immunodeficiency virus (HIV) nucleic acids were detected with the use of a 3H-labeled cDNA probe with an in situ hybridization method in 11 bone marrow samples (three ARC and eight AIDS). Most commonly positive cells were mononucleated, resembling lymphocytes and histiocytes. Endothelial cells, interdigitating reticulum cells, nucleated red blood cells, and immature myeloid cells also had positive results in some instances. The number of HIV-positive cells was not related to the size of the bone biopsies or the clinical diagnoses. The authors postulate that changes in the peripheral blood and bone marrow of these patients may be related to latent persistent infection with HIV.  相似文献   
3.
Ultrasound (US) imaging is a safe alternative to radiography for guidance during minimally invasive orthopedic procedures. However, ultrasound is challenging to interpret because of the relatively low signal-to-noise ratio and its inherent speckle pattern that decreases image quality. Here we describe a method for automatic bone segmentation in 2-D ultrasound images using a patch-based random forest classifier and several ultrasound specific features, such as shadowing. We illustrate that existing shadow features are not robust to changes in US acquisition parameters, and propose a novel robust shadow feature. We evaluate the method on several US data sets and report that it favorably compares with existing techniques. We achieve a recall of 0.86 at a precision of 0.82 on a test set of 143 spinal US images.  相似文献   
4.
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   
5.
Oncolytic adenoviral vectors are a promising alternative for the treatment of glioblastoma. Recent publications have demonstrated the advantages of shielding viral particles within cellular vehicles (CVs), which can be targeted towards the tumor microenvironment. Here, we studied T-cells, often having a natural capacity to target tumors, for their feasibility as a CV to deliver the oncolytic adenovirus, Delta24-RGD, to glioblastoma. The Jurkat T-cell line was assessed in co-culture with the glioblastoma stem cell (GSC) line, MGG8, for the optimal transfer conditions of Delta24-RGD in vitro. The effect of intraparenchymal and tail vein injections on intratumoral virus distribution and overall survival was addressed in an orthotopic glioma stem cell (GSC)-based xenograft model. Jurkat T-cells were demonstrated to facilitate the amplification and transfer of Delta24-RGD onto GSCs. Delta24-RGD dosing and incubation time were found to influence the migratory ability of T-cells towards GSCs. Injection of Delta24-RGD-loaded T-cells into the brains of GSC-bearing mice led to migration towards the tumor and dispersion of the virus within the tumor core and infiltrative zones. This occurred after injection into the ipsilateral hemisphere, as well as into the non-tumor-bearing hemisphere. We found that T-cell-mediated delivery of Delta24-RGD led to the inhibition of tumor growth compared to non-treated controls, resulting in prolonged survival (p = 0.007). Systemic administration of virus-loaded T-cells resulted in intratumoral viral delivery, albeit at low levels. Based on these findings, we conclude that T-cell-based CVs are a feasible approach to local Delta24-RGD delivery in glioblastoma, although efficient systemic targeting requires further improvement.  相似文献   
6.
Disorders of balance and gait have been observed in patients with essential tremor (ET), but their association with tremor severity remains unclear. This study aimed to evaluate postural instability and gait changes in ET patients and to investigate their relationship to tremor characteristics with regard to cerebellar dysfunction as a possible common pathogenetic mechanism in ET. Thirty ET patients (8F, mean (SD) age 55.8 (17.8), range 19–81 years) and 25 normal controls (7F, 53.0 (17.7), 19–81) were tested with the scales of Activities-specific Balance Confidence (ABC), Fullerton Advanced Balance (FAB), and International Cooperative Ataxia Rating Scale (ICARS). Posturography and gait were assessed using a Footscan® system. Tremor was evaluated by the Fahn–Tolosa–Marin Tremor Rating Scale (TRS) and accelerometry in five upper limb positions. A mean (SD) TRS sum score of 27.0 (13.2) corresponded to mild to moderate tremor severity in most patients. In comparison with controls, ET subjects exhibited lower tandem gait velocity (0.21 vs. 0.26 m/s, P?=?0.028), more missteps (0.57 vs. 0.12, P?=?0.039), and increased postural sway in tandem stance (sway area 301.1 vs. 202.9 mm2, P?=?0.045). In normal gait, step width increased with the midline tremor subscore of TRS (Pearson r?=?0.60, P?=?0.046). Moreover, significant correlations were found between age and quantitative measures of normal and tandem gait in ET patients but not in controls. ABC, FAB, and ICARS scores did not significantly differ between patients and controls. In conclusion, gait and balance alterations in ET patients occur even without subjective complaints. Their relationship with midline tremor and dependence on age suggest a connection with cerebellar dysfunction.  相似文献   
7.
We report a severe acute respiratory syndrome coronavirus 2 superspreading event in the Netherlands after distancing rules were lifted in nightclubs, despite requiring a negative test or vaccination. This occurrence illustrates the potential for rapid dissemination of variants in largely unvaccinated populations under such conditions. We detected subsequent community transmission of this strain.  相似文献   
8.
The Id family of helix-loop-helix proteins is involved in a variety of processes, such as development, proliferation, and angiogenesis. In this study, we investigated the expression pattern of Id1, Id2, and Id3 in surgical specimens of human glial tumors. Western blot analysis demonstrated that all three Id proteins were expressed in astrocytic tumors. Expression levels in high-grade tumors were higher than in low-grade tumors. Immunohistochemical analysis confirmed that many of the tumor astrocytes exhibited strong Id1-3 IR. In contrast, in adult human normal brain, Id expression was low both in resting astrocytes and in endothelial cells. In tumor cells, Id proteins displayed cytoplasmic as well as nuclear localization. Id1-3 IR scores in tumor cells were positively correlated with proliferation indices. Moreover, Id1-3 IR was detected in endothelial cells of the astrocytic tumor blood vessels. The vascular Id1-3 expression correlated positively with tumor vascularity and grade. These results support the role of the Id gene family in the enhanced proliferative potential of tumor astrocytes. The evidence also supports the involvement of the Id gene family in tumor angiogenesis, a process that critically influences the malignant behavior of glial tumors.  相似文献   
9.
Type 1 diabetes incidence increases at about 3% per year in the Western world. From genetically predisposed people only 20-50% develop the disease. To unravel these mysteries, literature was searched to determine the disease background and to find suggestions for research and prevention. A promising hypothesis was found: the enzyme glutamic acid decarboxylase (GAD) in bacteria may be the source of type 1 diabetes. Epidemiological data can be accounted for this possibility. GAD-containing bacteria can originate from raw foods, especially salted or dried or smoked raw meat and fish products or from proliferation in the ileum of the human small intestine. Proliferation of GAD-containing bacteria in the ileum is probably the most frequent causation of type 1 diabetes. This proliferation is stimulated by the consumption of nitrate-containing ingredients such as vegetables, fruits or nitrate-polluted water and by sugars dissolved in liquids, for example lactose in milk or sugars in juicy fruits and fruit-juices. In the ileum GAD is released from bacteria by endocrine enzymes of the small intestine. Released GAD enters Peyer's patches (PP) in the ileum wall, where it is bound or enclosed by immune cells. These cells move GAD by the lymph- and bloodstream to the immune system for priming and elimination. In case of type 1 diabetes, however, malfunction of PP causes GAD freely move in the lymph stream where it settles on vascular endothelial cells and pancreatic beta-cells. GAD-settlement on beta-cells gives an inflammatory immune response, leading to destruction of the beta-cells and to type 1 diabetes. A perspective for prevention of the disease in predisposed individuals is discussed. It is concluded that GAD-containing bacteria and malfunction of PP should be taken into account in future type 1 diabetes research.  相似文献   
10.
College students and a subsample of their mothers and fathers participated in a study examining their retrospective reports of childhood emotional and behavioral problems experienced by college students. College students and their mothers and fathers exhibited moderate correspondence in their recollection of internalizing and externalizing problems that college students experienced during their childhood. In contrast, college students tended to endorse significantly greater levels of both internalizing and externalizing problems relative to their mothers and fathers. Current psychological symptoms predicted the greater endorsement of childhood internalizing and externalizing problems by college students and the greater endorsement of college students' childhood internalizing problems by their mothers. Further, college students' current perceptions of their parents predicted their endorsement of childhood internalizing problems, and college students' current masculinity and femininity predicted their endorsement of childhood externalizing problems. Results of this study emphasized the importance of noting factors that may be related to retrospective reports.  相似文献   
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