The production of nitric oxide (NO) by macrophages is important for the killing of intracellular pathogens, such as Toxoplasma gondii. Gamma interferon (IFN-gamma) and lipopolysaccharide stimulate NO production. The aim of this study was to investigate the importance of NO, IFN-gamma and interleukin-12 (IL-12) in the host immune response in AIDS patients suffering from toxoplasmic encephalitis (TE). It was demonstrated that the production of NO, detected as nitrite/nitrate in the sera and in the cerebrospinal fluid (CSF) of 32 AIDS patients with TE, was normal. In addition, levels of IFN-gamma in the sera and in the CSF of patients with TE were not increased. In contrast, serum levels of IL-12 in these patients were significantly increased (6.5 +/- 7.1 pg/ml; P = 0.0368), compared to the control patients (1.7 +/- 3.5 pg/ml). Furthermore, increased but not significant levels of IL-12 were also observed in the CSF of patients with TE (2.2 +/- 4.7 pg/ml; controls: 0.5 +/- 1.9 pg/ml). The results of this study indicate that reactivation or recurrence of T. gondii infection in HIV-1-infected patients is probably due to a down-regulation of IFN-gamma along with a resulting non-optimal NO activity.

AIDS-Related Opportunistic Infections↗

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Calculated energy dependence of some RTL and RPL detectors.

Explore the source record for details and available documents.

Film Dosimetry↗

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3D modeling of phased array generated ultrasounds in lossy media.

A general algorithm for three-dimensional (3D) modeling of acoustic fields generated by phased array transducers and propagating in uniformly lossy media is introduced and illustrated also with the help of specific examples. Applications of the method are foreseen in the analysis and the design of transducers for echographic applications in order to evaluate and/or optimize their performances.

Acoustics↗

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CT of renal metastatic disease. A pictorial essay.

The routine use of computed tomography (CT) for the staging and follow-up of malignant neoplasm has improved the detection of secondary spread to the kidneys. This essay illustrates the gamut of the CT aspects of such secondary lesions. Seven main patterns of metastatic features are identified. Some of these patterns appear to reproduce the same radiological features seen in the corresponding primary lesions. Where feasible, differential diagnostic criteria are offered.

Adult↗

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CT of secondary neoplasms. Unusual structural features--a pictorial essay.

The newer anticancer therapies, the routine employment of cross-sectional imaging modalities for staging and follow-up, and the increased survival rate of patients with neoplastic lesions have markedly widened the range of pathological and imaging features of secondary neoplasms. Moreover, the changes occurring in morphological and structural aspects of metastases may be the direct effect of the improved therapeutic tools, and in turn may offer revealing clues to the clinician regarding the outcome of therapy itself. The scope of this essay is to show the atypical computed tomographic (CT) aspects of a series of metastatic lesions. We selected the lesions on the basis of their unusual structural features, such as calcification; hemorrhage; superinfection; pseudocystic, cystic, and lipoid appearance; and hypervascularity. A highly detailed assessment of such changes is nowadays possible and appears mandatory.

Female↗

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US and CT findings of secondary neoplasms of the thyroid--a pictorial essay.

Although clinical series report a low (3%) incidence of metastases to the thyroid gland, autoptic studies have showed occurrences as high as 17%, probably because of the high vascularization of the thyroid. We selected 9 patients who had pathologically proven thyroid metastases at CT and US, during follow-up for a known primary neoplasm. The most common originating neoplastic primaries include mostly those that generally give rise to blood-borne metastases such as breast and lung cancers, mucoid adenocarcinoma of the stomach, colon cancer and renal cancer, as well as melanoma and leiomyosarcoma. Because of its diffusion, sensitivity, and noninvasiveness, ultrasonography can justifiably be introduced in the staging protocols of those neoplasm that more frequently give blood-borne metastases to the thyroid, but a US-guided biopsy is warranted for hypoechoic or otherwise suspicious nodules. This holds particularly true in disease-free patients or previously diagnosed with generally slow-growing malignancies (breast or kidney), since the secondary localization, often metachronous in our experience, may be effectively managed surgically. CT features, on the other hand, are extremely variable and are directly dependent on the histology of the primary lesion, as well as the size of the secondary lesions.

Aged↗

PubMedDate not supplied

Thin-section CT follow-up of metastatic ovarian carcinoma correlation with levels of CA-125 marker and clinical history.

Second-look laparotomy and CA-125 are the gold standard in follow-up of ovarian carcinoma. Since no definite role seems established for cross-sectional imaging in assessment of recurrence we employed thin-section computed tomography (CT), correlated with CA-125 levels and detailed knowledge of the clinical history as a follow-up protocol One hundred seventy-seven patients with ovarian carcinoma were selected because of: (a) pathologically proven remission after first-line chemotherapy, (b) follow-up by means of thin-section CT every 6 months for the fist 3 years and every 10 months subsequently, (c) monitoring CA-125 serum levels every 3 months for the first 3 years and every 6 months subsequently; (d) pathologic confirmation or clinical and laboratory follow-up after 12 months or longer for the CT findings. Fifty percent of the patients showed recurrence of disease. Our protocol yielded 93.2% true positive, dubious findings in 5.6% 1.0% false negatives, 97.7% true negative, and 2.3% false positive. With a tailored technique, CT was particularly sensitive in early diagnosis of peritoneal seeding, even in the absence of ascites or increases in the levels of CA-125. Repeated administration of contrast medium, water enemas, and repeated scanning of suspicious volumes with differing scanning parameters were the factors managed by the radiologist. We conclude that thin-section CT, correlated with CA-125 levels and careful review of the clinical history could represent a valid alternative to repeated explorative laparotomies in the follow-up of ovarian carcinomas.

Adult↗

PubMedDate not supplied