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1.
Campylobacter jejuni (C. jejunj) infection is the most common antecedent in the axonal variant of Guillain‐Barré syndrome (GBS). Antibodies against nerve gangliosides found in GBS patients recognize cross‐reactive epitopes in the lipopolysaccharide (LPS) of C. jejuni. This led to the molecular mimicry hypothesis of GBS. We immunized eleven rabbits with a LPS extracted from HS:19 C. jejuni strain isolated from a patient with GBS and complete Freund's adjuvant (CFA)(group I). In a second experiment we immunized seven rabbits with LPS, CFA and keyhole limpet hemocyanin (KLH)(group II). All group I rabbits developed high titers of anti‐LPS, anti‐GM1, anti‐GD1b antibodies and lower titers of anti‐GD1a. One rabbit, 50 days after initial inoculation, showed tremor and weakness. All rabbits of group II developed high titres of antiganglioside antibodies and six animals showed weakness 59–113 days after initial inoculation. Two rabbits died. Pathology showed mild to moderate, tendentially grouped, axonal degeneration in sciatic nerves of four out of five animals. Control rabbits of group I (immunized with CFA only) did not develop antibodies, controls of group II (immunized with CFA + KLH) developed low titers of IgG anti‐GM1. None developed neurological signs or showed axonal degeneration. C. jejuni LPS is a potent B‐cell stimulator capable to induce a strong antiganglioside response in rabbits. However, to induce the neuropathy is crucial to employ KLH, a glycoprotein known to stimulate both humoral and cellular responses. This animal model reproduces the pathogenetic process hypothesized in axonal GBS with antiganglioside antibodies post C. jejuni infection.  相似文献   
2.
S100A1 is a calcium-binding protein, which has been recently found in renal cell neoplasms. We evaluated the diagnostic utility of immunohistochemical detection of S100A1 in 164 renal cell neoplasms. Forty-one clear cell, 32 papillary, and 51 chromophobe renal cell carcinomas, and 40 oncocytomas, 164 samples of normal renal parenchyma adjacent to the tumors and 13 fetal kidneys were analyzed. The levels of S100A1 mRNA detected by quantitative RT-PCR analysis of frozen tissues from seven clear cell, five papillary, and six chromophobe renal cell carcinomas, four oncocytomas, and nine samples of normal renal tissues adjacent to neoplasms were compared with the immunohistochemical detection of protein expression. Clear cell and papillary renal cell carcinomas showed positive reactions for S100A1 in 30 out of 41 tumors (73%) and in 30 out of 32 (94%) tumors, respectively. Thirty-seven renal oncocytomas out of 40 (93%) were positive for S100A1, whereas 48 of 51 (94%) chromophobe renal cell carcinomas were negative. S100A1 protein was detected in all samples of unaffected and fetal kidneys. S100A1 mRNA was detected by RT-PCR in all normal kidneys and renal cell neoplasms, although at very different levels. Statistical analyses comparing the different expression of S100A1 in clear cell and chromophobe renal cell carcinomas observed by immunohistochemical and RT-PCR methods showed significant values (P<0.001), such as when comparing by both techniques the different levels of S100A1 expression in chromophobe renal cell carcinomas and oncocytomas (P<0.001). Our study shows that S100A1 protein is expressed in oncocytomas, clear cell and papillary renal cell carcinomas but not in chromophobe renal cell carcinomas. Its immunodetection is potentially useful for the differential diagnosis between chromophobe renal cell carcinoma and oncocytoma. Further, S100A1 protein expression is constantly detected in the normal parenchyma of the adult and fetal kidney.  相似文献   
3.
4.
Background: We have investigated the vascular perfusion of a wide variety of conditions of the anterior segment using fluorescein angiography.
Methods: The conditions were classified and findings reported according to the system set out below. Patients underwent full ocular examination. Fluorescein angiography of the anterior segment was carried out when indicated to investigate iris atrophy and neovascularisation. Specular microscopy of the corneal endothelium was used to detect changes in this tissue.
Results: The hypoperfusion was variable in degree and accompanied by varying degrees of iris hypoplasia and atrophy with neovascularisation. The degree of neovascularisation depended upon its rapidity of development, the pre-existing state of vascular perfusion and the underlying pathological condition.
Conclusions: Hypoperfusion with resultant ischaemia and neovascularisation is common in conditions of the anterior segment. An understanding of the changes is valuable in treating many conditions affecting the anterior segment. The changes observed may also occur elsewhere in the physical system and may be a significant part of the ageing process, either as scattered, disparate processes or as part of a general disease process.  相似文献   
5.
Postoperative radiation therapy in the management of lung cancer   总被引:1,自引:0,他引:1  
Postoperative radiation therapy for lung cancer is still controversial. In a 9-year period, 69 patients with non-oat-cell carcinoma of the lung (16% stage I, 26% stage II, and 58% stage III) received such therapy. The radiation dose was less than 5,000 cGy in 42 patients, 5,000-5,900 cGy in 16, and 6,000 cGy or more in 11; follow-up ranged from 24 to 64 months. Actuarial survival at 2 and 4 years was 50% and 16%, respectively, for squamous cell carcinoma, and 40% and 26% for adenocarcinoma. The 5-year survival for stages I, II, and III cancer was 29%, 17%, and 19%, respectively. Histologic findings and type of surgery did not affect survival, but the radiation dose apparently did. The 3-year survival for patients who received less than 6,000 cGy was 35%, compared with 73% for patients who received higher doses. In eight patients, treatment failed within the irradiated volume: all had received doses of less than 6,000 cGy, and the volume in three was judged to be inadequate.  相似文献   
6.
Previous work has shown that treatment with thyroid hormone (T3) decreased the incidence of rat hepatocellular carcinoma (HCC). The present study was designed to determine whether the inhibitory effect of T3 on HCC development was limited to early steps of the carcinogenetic process or, whether a similar effect could also be exerted by starting T3 treatment at later stages. Hepatic nodules were induced in Fischer rats by a single dose of DENA, followed by a 2-week exposure of the animals to 2-AAF and partial hepatectomy. Rats were then divided into 3 groups: group 1 was maintained on basal diet: group 2 was fed a diet containing 4 mg/kg T3 for a week, every month/7 months, starting 9 weeks after DENA administration: group 3 was exposed to cycles of T3 starting 8 months after initiation. Results demonstrate that inhibition of HCC development was essentially similar in rats exposed to T3 starting either 9 weeks or 8 months after initiation (50% inhibition compared to control rats). We have previously shown that T3-induced nodule regression and HCC inhibition occurred in spite of its mitogenic effect. Therefore, we next wished to determine whether a similar antitumoral effect could be exerted by other liver mitogens, such as peroxisome proliferators. Rats exposed to the initiation-promotion protocol described previously, were subjected to 11 cycles of a T3 or a ciprofibrate-supplemented diet, each cycle consisting of 7 days/month: the incidence of HCC and lung metastases was determined 13.5 months after initiation. Results showed that although treatment with T3 strongly inhibited HCC development (only 31% of T3+ rats showed HCC vs 91% of controls), rats given ciprofibrate developed the same number of HCC as T3-untreated rats. In conclusion, the results of this study showed that the anticarcinogenic effect of T3 is maintained also when treatment begins late in the process, and its antitumoral property appears to be specific and may not be shared by other liver mitogens.  相似文献   
7.
The systematic screening of 253 children with transfusion-dependent homozygous beta-thalassaemia revealed a high incidence of hepatitis B virus markers. The highest frequencies of hepatitis B surface antigen (HBsAg) and antibody to hepatitis B core antigen (anti-HBc) were found in the group of patients with the smallest number of transfusions, while the highest frequency of antibody to hepatitis B surface antigen (anti-HBs) was detected in the patients who had had the largest number of transfusions. Follow-up of these patients showed (a) a high incidence of acute hepatitis B, which was mainly subclinical; (b) normal hepatitis B surface antigen clearance and normal antibody to hepatitis B surface development; and (c) a high frequency of increased transaminase values for over six months. In all the subjects with persistently high transaminase, histological examination revealed chronic persistent hepatitis or chronic active hepatitis. Apart from two cases of chronic active hepatitis with no B virus markers, and two cases of chronic persistent hepatitis with HBsAg and anti-HBc in the serum, all these subjects were anti-HBs positive but HGsAg and anti-HBc negative.  相似文献   
8.
A cultural effect on brain function   总被引:3,自引:0,他引:3  
We present behavioral and anatomical evidence for a multi-component reading system in which different components are differentially weighted depending on culture-specific demands of orthography. Italian orthography is consistent, enabling reliable conversion of graphemes to phonemes to yield correct pronunciation of the word. English orthography is inconsistent, complicating mapping of letters to word sounds. In behavioral studies, Italian students showed faster word and non-word reading than English students. In two PET studies, Italians showed greater activation in left superior temporal regions associated with phoneme processing. In contrast, English readers showed greater activations, particularly for non-words, in left posterior inferior temporal gyrus and anterior inferior frontal gyrus, areas associated with word retrieval during both reading and naming tasks.  相似文献   
9.
We designed an open, non-randomized clinical study to assess as the first endpoint the feasibility of sparing surgery and of preserving organ/function by using neo-adjuvant chemotherapy (NAG) in oral cavity and oropharynx cancer patients, and, as the second endpoint, the clinical response to this treatment approach and its duration. Moreover, an attempt was made to scale the extent of surgery by means of an Arbitrary Scale assigning different percentages to the different extents of surgical resection. Twenty-five patients with primary oral cavity and oropharynx cancer (stage III-TV) were enrolled in the study and were assigned to either the classical Al-Sarrafs regimen (1) (n=15) or to a regimen (2) consisting of cisplatin 80 mg/m(2) i.v. on day 1, 5-FU 600 mg/m(2) on days 2-5 and vinorelbine 20 mg/m(2) on days 2 and 8 (n=10). The 25 patients were all evaluable for response to NAC and 20 of them were evaluable for organ preservation. The overall response (OR) rate was 86.6% (13/15 patients) for regimen 1 (cisplatin + 5-FU) and 80% (8/10 patients) for regimen 2 (cisplatin + 5-FU + vinorelbine). The median follow-up duration was 20.6 months. 5/20 (25%) patients completely avoided surgery, 5/20 (25%) patients had a reduced extent of surgical resection, while: 10/20 (50%) patients received the previously planned surgical resection. Altogether, 10/20 (50%) patients treated with NAC either avoided or achieved a reduction in the previously planned surgical resection. Moreover, organ function was evaluated to support the assessment of treatment outcome in our patients. For this purpose we selected the Performance Status Scale for Head and Neck Cancer Patients: as expected, no significant impairment was detected in the area of comprehensibility of speech, but we were rather surprised that no significant impairment was found in the two areas of eating in public and normalcy of diet. NAG-associated toxicity was moderate and similar in the two chemotherapy regimens. The most relevant contributions offered by our study are represented by i) a Scale aimed at measuring as precisely as possible the reduction of surgical resection made possible by NAC compared to surgery planned before NAC and ii) an attempt to support the results with an assessment of treatment outcome.  相似文献   
10.
The aim of the present study was to verify whether the CMI response of the host's lymphocytes is directed towards tumor-associated antigens (TAA) specific for each histological type of tumor. The leucocyte migration inhibition (LMI) test was selected for this purpose, utilizing the cancer patients' leucocytes and, as neoplastic antigens, formalin-fixed cells of surgically removed cancer tissue. Two hundred and eighteen patients were studied, 110 of whom were affected by breast cancer, 48 by digestive tract and 60 by laryngeal cancer. The total amount of tests performed was 278. The leucocytes of 93 normal subjects were tested against the different tissues' cancer antigens, as were the leucocytes of 41 patients with cancer of different organs tested against the corresponding normal tissues' antigens. The breast cancer patients (122 tests performed) showed 82.35% positive tests against homologous antigen, 72.72% and 95.24% against heterologous (digestive tract and laryngeal cancer, respectively) antigens. The digestive tract cancer patients (69 tests performed) showed 70.27% positive tests against homologous, 66.66% and 43.48% against heterologous antigens (breast and laryngeal cancer respectively). The laryngeal cancer patients (87 tests performed) showed 74.29% positive tests against homologous, 38.10% and 80.65% against heterologous antigens (breast and digestive tract, respectively). The results led to the conclusion that the LMI test response of cancer patients was not "tissue specific": the test did not discriminate between the homologous and the heterologous cancer antigens, and it seems that the response was not directed towards specific TAA but only towards wide-range or "group" TAA, showed by several types of tumors.  相似文献   
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