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Kundel HL; Gefter W; Aronchick J; Miller W Jr; Hatabu H; Whitfill CH; Miller W Sr 《Radiology》1997,205(3):859
5.
Anorexia and cachexia frequently complicate the late stages of malignancy and may be a prominent feature of early disease. The resulting weight loss often becomes a major focus of concern for the patient and the family and may significantly add to the morbidity and mortality of cancer. Factors which contribute to the wasting syndrome include the effects of the tumour, effects of chemotherapy, abnormalities of carbohydrate, fat and protein metabolism and the cytokine response. Administration of total parenteral nutrition (TPN) is an important method of addressing malnutrition, particularly in patients with nonfunctioning gastrointestinal tracts. A critical review of the TPN cancer literature is provided along with a discussion of new approaches and future directions in the nutritional support of patients with malignant disease, such as anabolic agents, hydrazine sulfate and megestrol. 相似文献
6.
Superficial siderosis of the central nervous system is a rare, often unrecognized condition in which there is a deposition of intracellular and extracellular hemosiderin in the leptomeninges, subpial tissue, spinal cord, and cranial nerves as a result of chronic bleeding in the subarachnoid space. On the basis of our cases and a review of the literature, the majority of patients manifest sensorineural hearing loss in addition to cerebellar dysfunction, pyramidal tract signs, and progressive mental deterioration. Recent imaging techniques--particularly CT and MRI--can define the presence of iron deposition, confirming the diagnosis ante mortem. From post mortem specimens, histologic sections demonstrate severe damage to the eighth nerve, with microglial metabolism of iron. Cases will be presented to illustrate these points. 相似文献
7.
Most pediatric cochlear implant programs support a team approach for post-implant services. However, individuals directly involved in the care of these children often have differing opinions on the child's performance. We describe our experience with four children, aged 3 to 10 at the time of implantation, who have used the Nucleus 22-channel cochlear implant device for at least nine months. A questionnaire, focusing on the individual's observations of the child's speech and hearing performance in their particular setting (i.e., clinic, home, school), was completed by the child's parent(s), therapist and classroom teacher. Overall, performance in structured settings (i.e., testing and therapy sessions) was not in agreement with performance in unstructured settings (i.e., classroom and home environments). The results suggest that different individuals interacting with the same child in different environments often have differing perceptions of the child's performance. Based on the information obtained on the four cases, we discuss factors to consider in assessing the real-life performance of pediatric cochlear implant recipients. 相似文献
8.
CTLA-4 is required for the induction of high dose oral tolerance 总被引:5,自引:3,他引:5
Samoilova EB; Horton JL; Zhang H; Khoury SJ; Weiner HL; Chen Y 《International immunology》1998,10(4):491-498
Mucosal and systemic administrations of high dose antigens induce long-
lasting peripheral T cell tolerance. We and others have shown that high
dose peripheral T cell tolerance is mediated by anergy or deletion and is
preceded by T cell activation. Co-stimulatory molecules B7-1 (CD80)/B7-2
(CD86) and their counter-receptors CD28/CTLA-4 play pivotal roles in T cell
activation and immune regulation. In the present study, we examined the
roles of the B7 co-stimulation pathway in the generation of high dose
peripheral T cell tolerance. We found that blocking B7:CD28/CTLA-4
interaction at the time of tolerance induction partially prevented T cell
tolerance, whereas selective blockade of B7:CTLA-4 interaction completely
abrogated peripheral T cell tolerance induced by either oral or i.p.
antigens. These results suggest that CTLA-4-mediated feedback regulation
plays a crucial role in the induction of high dose peripheral T cell
tolerance.
相似文献
9.
Molecular genetic characterization of XRCC4 function 总被引:2,自引:0,他引:2
XRCC4 is a generally expressed protein of 334 amino acids that is involved
in the repair of DNA double-strand breaks and in V(D)J recombination, but
its function is unknown. In this study, we have used a mutational approach
and the yeast two-hybrid method to perform an initial characterization of
this protein. We show that the XRCC4 protein is located in the nucleus. We
also demonstrate that several potential phosphorylation sites are not
required for XRCC4 function in a transient V(D)J recombination assay. In
addition, we show that XRCC4 forms a homodimer in vivo with the
homodimerization domain being located within amino acids 115-204. Finally,
we define a core domain of XRCC4 that functions in V(D)J recombination and
comprises amino acids 18-204. Potential functions of XRCC4 are discussed.
相似文献
10.
Liu JQ; Bai XF; Shi FD; Xiao BG; Li HL; Levi M; Mustafa M; Wahren B; Link H 《International immunology》1998,10(8):1139-1148
Induction of mucosal tolerance by inhalation of soluble peptides with
defined T cell epitopes is receiving much attention as a means of
specifically down-regulating pathogenic T cell reactivities in autoimmune
and allergic disorders. Experimental autoimmune encephalomyelitis (EAE)
induced in the Lewis rat by immunization with myelin basic protein (MBP)
and Freund's adjuvant (CFA) is mediated by CD4+ T cells specific for the
MBP amino acid sequences 68-86 and 87-99. To further define the principles
of nasal tolerance induction, we generated three different MBP peptides
(MBP 68-86, 87-99 and the non- encephalitogenic peptide 110-128), and
evaluated whether their nasal administration on day -11, -10, -9, -8 and -7
prior to immunization with guinea pig MBP (gp-MBP) + CFA confers protection
to Lewis rat EAE. Protection was achieved with the encephalitogenic
peptides MBP 68-86 and 87-99, MBP 68-86 being more potent, but not with MBP
110-128. Neither MBP 68-86 nor 87-99 at doses used conferred complete
protection to gp-MBP-induced EAE. In contrast, nasal administration of a
mixture of MBP 68-86 and 87-99 completely blocked gp-MBP-induced EAE even
at lower dosage compared to that being used for individual peptides. Rats
tolerized with MBP 68-86 + 87-99 nasally showed decreased T cell responses
to MBP reflected by lymphocyte proliferation and IFN-gamma ELISPOT assays.
Rats tolerized with MBP 68-86 + 87-99 also had abrogated MBP-reactive
IFN-gamma and tumor necrosis factor-alpha mRNA expression in lymph node
cells compared to rats receiving MBP 110-128 nasally, while similar low
levels of MBP-reactive transforming growth factor-beta and IL-4 mRNA
expressing cells were observed in the two groups. Nasal administration of
MBP 68-86 + 87-99 only slightly inhibited guinea pig spinal cord
homogenate-induced EAE, and passive transfer of spleen mononuclear cells
from MBP 68-86 + 87-99-tolerized rats did not protect naive rats from EAE.
Finally, we show that nasal administration of MBP 68-86 + 87-99 can reverse
ongoing EAE induced with gp-MBP, although higher doses are required
compared to the dosage needed for prevention. In conclusion, nasal
administration of encephalitogenic MBP peptides can induce antigen-specific
T cell tolerance and confer incomplete protection to gp-MBP-induced EAE,
and MBP 68-86 and 87-99 have synergistic effects. Non-regulatory mechanisms
are proposed to be responsible for tolerance development after nasal
peptide administration.
相似文献