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A Blum

Publications and source records attributed to A Blum.

At least 163 records · Page 9Linked to original sources
PubMed1996

What Models of Granulomatous Inflammation Provide the Immunologist

Granulomas usually serve to protect the host from the spread of persistent microorganisms or other enduring injurious substances. They are complex inflammatory reactions that use many immune mechanisms to control the inciting nudis. These lesions can persist for weeks, months, or even years. Thus, understanding the mechanisms that enhance, diminish, or modulate granulomas could aid in the treatment of many diseases. Moreover, experimental animal models of granulomatous inflammation allow sophisticated investigation of some disease processes not possible using human subjects. Granulomatous inflammations are chronic, composed of activated leukocytes that are selected for deposition at the site of injury. They use various effector mechanisms, delicately balanced by many immunoregulatory circuits. Under some experimental conditions, granulomas can be isolated readily from host tissue and subjected to sophisticated immunological analysis. Therefore, it is possible to dissect the actual, local control mechanisms that govern the granulomatous response. Lesions learned studying granulomas are applicable to other types of inflammation, since granulomas use immunoregulatory networks and soluble cytokines common to many inflammatory states. Using these experimental models, it is readily apparent that studies utilizing splenocytes or peripheral blood leukocytes may not reveal the true, dominant immunoregulatory mechanisms employed at sites of active inflammation. The leukocytes of spleens and blood are a mixture of cells in various stages of activation, many of which are not destined to participate in a selective immune response. Also, granulomas are sustained inflammatory reactions permitting analysis of the unique features of chronic maintenance, as opposed to acute phase inflammation.

Journal Article↗
PubMed1996

Substance P receptor antagonist inhibits murine IgM expression in developing schistosome granulomas by blocking the terminal differentiation of intragranuloma B cells.

Schistosome granulomas make substance P (SP). CP96,345 is a nonpeptide SP receptor antagonist active in vivo. Granulomas that form in the presence of SP receptor blockade produce little IgM as compared to normal lesions. The objective of this study was to determine how CP96,345 modulates granuloma IgM production. Schistosome ova were embolized to the lungs of infected mice to induce granulomas of synchronous age. Animals received CP96,345 (50 mg/kg/day) for 4 days following egg embolization. Then granulomas were isolated from tissue and dispersed into single-cell preparations. The dispersed granuloma cells were cultured in vitro to measure IgM and cytokine secretion. Also, granuloma B cells were studied using an IgM ELISPOT assay and flow cytometry. As expected, mice treated with CP96,345 formed granulomas that secreted little IgM. Granulomas from CP96,345-treated mice, as compared to buffer-treated animals, contained few IgM-secreting B lymphocytes, but had appropriate numbers of B cells expressing surface IgM. Also decreased was the capacity of the granulomas to make IFN-gamma, IL-4, IL-5 and IL-6. CP96,345 treatment did not affect splenocyte IgM or cytokine synthesis. These data suggest that CP96,345 inhibits granuloma IgM secretion by blocking intragranuloma B cell maturation at a terminal stage of B cell differentiation. Moreover, SP receptor antagonist affects a variety of cytokine circuits that could influence IgM B cell maturation in vivo.

Animals↗
PubMed1996

[Spiral scanners: principles and clinical prospects].

Helical computed tomography (CT) involves continuous patient shifting during X-ray source rotation and data acquisition. As a result, a volume data set is obtained in a short period of time. An entire examination can be completed in a single breath hold, without additional radiation exposure, optimizing enhancement with intravenous contrast material. By overcoming some of the constraints of conventional CT, helical CT has advanced prospects, including multiplanar reconstruction and CT angiography, as reviewed in this article. There are undergoing studies to confirm these preliminary findings: its clinical applications are currently evolving.

Bone Diseases↗
PubMed1996

[Actinomycosis and non-Hodgkin's malignant lymphoma: fortuitous association?].

Two cases of actinomycosis associated with non Hodgkin's lymphoma (NHL) are reported. In one case, low grade NHL was diagnosed many years after actinomycosis because of the persistence of abdominal lymphadenopathy in spite of antibiotic therapy. In the second case, hepatic metastasis were initially suspected until actinomycosis diagnosis was made by percutaneous liver biopsy under scanography. High grade NHL was diagnosed by laparotomy and liver biopsy performed 6 weeks after the onset of antibiotic therapy as no improvement in hepatic lesions was obtained. These two case reports outline the difficulties encountered in the diagnosis of actinomycosis and the indication of a repeat biopsy when actinomycosis does not respond to antimicrobial therapy because of the possibility of concomitant malignancy.

Actinomycosis↗
PubMed1996

Nuptiality, fertility, use of contraception, and family policies in Uzbekistan.

With more than 22 million inhabitants, Uzbekistan is the most populous of the Central Asian republics of the former USSR. Using data from a retrospective survey conducted in 1992 among women of reproductive age, the paper examines fertility trends and determinants during the twentieth century. The analysis shows that the absence of a government-supported birth control programme and the strong pro-natalist policies of the Soviet authorities during most of the century did not affect either the onset, nor the progress of the fertility transition. The results indicate, however, that the social development programmes undertaken by the Soviet government did play a very active part in the transition as shown by the impact of education on reproductive behaviour, as well as on the very specific contraceptive mix adopted by the population after the mid-1970s.

Contraception↗
PubMed1996

[Radiologic aspects of endoscopic sphincterotomy complications].

Endoscopic sphincterotomy (ES) is a minimally invasive technique which is the standard of reference in many clinical situations (e.g distal choledocolithiasis, recurrent lithiasis or bile duct stenosis). Complication are rare but are often misdiagnosed although radiological aspects are demonstrative. The purpose of this study is to illustrate the patterns of the complications. Ten patients have been treated for the last four years in our institution for ES complications. There were eight cases of pancreatitis, three of which had associated perforation, one arterioportal fistula, and one isolated perforation. Diagnosis was reached with CT in all but one case. Two patients have been successfully treated with percutaneous treatment (one embolization with Gianturco coils, and one drainage). Two patients died, one of necrotizing pancreatitis and the second of decubitus complication. The other patient were followed with CT. We give exemples of different observations and discuss their follow up. The severity and extent of post ES pancreatitis were readily assessed by CT and response to therapy monitored by serial examinations. Severity of disease, evaluated according to the length of hospitalization, correlated well with the presence and degree of pancreatic necrosis. CT also highlights perforations including minimal effusions. In our study differential diagnosis between post ES pancreatitis and perforation is not significant regarding the initial conservative therapy in both situations. CT scan helps us to opt for a surgical decision or for a percutaneous drainage. It also permits to follow the evolution of the lesions. In our cases involving perforations, we noted a spontaneous complete resolution of gas effusion on control and we also observed that pancreatitis evolution was similar to standard pancreatitis evolution. In a life threatening post ES hemobilia, not responding to standard medical treatment, angiography is the diagnostic exam of choice before embolization which is regarded as the best initial treatment of vascular lesions. We conclude that CT is the exam of choice in the initial diagnosis and follow up post ES complications.

Acute Disease↗
PubMed1996

The 'small-patella' syndrome. Hereditary osteodysplasia of the knee, pelvis and foot.

We describe a syndrome combining abnormalities of the pelvis, knee and foot in three related patients with a familial history of small dislocated patellae. The clinical and radiological appearance of the patella and pelvis is consistent with the 'small-patella' syndrome, a rare autosomal dominant disorder. There were also previously unreported deformities affecting the feet.

Adult↗
PubMed1996

The role of inflammation in atherosclerosis.

The vascular endothelium serves as a dynamic interface between circulating blood elements and the interstitial tissues. As such, it communicates with cells in the vessel wall as well as with the surrounding tissue, sensing its environment and responding accordingly. The vasculature must maintain a delicate balance when initiating a functional response by producing both pro-inflammatory and anti-inflammatory mediators, vasoconstrictors and vasodilators, growth stimulators and inhibitors, and prothrombotic and anti-thrombogenic factors. Any response to injurious agents could lead to pathologic responses. One response to injury by the endothelium is the new or increased expression of surface receptors for immune elements. In atherosclerosis, the adhesion of monocytes and T cells to the endothelium is a key event triggered by some form of insult. Subsequent events include monocytic infiltration of the vessel wall, alterations in lipid metabolism, and the activation of these cells into foam cells. The presence of large numbers of foam cells in the intima may produce a high concentration of cytokines and growth factors within a localized area, extracellular matrix perturbations, smooth muscle cell proliferation, and ultimately platelet aggregation at the site of stenosis. Endothelial cells will propagate an inflammatory response long after the initial insult to the arterial vessel. Thus, all of the cellular elements of the vessel wall, as well as the atherosclerotic plaque itself, produce adhesive molecules, cytokines and growth factors that amplify and propagate the pathologic process.

Animals↗
PubMed1995

T lymphocyte activation in stable angina pectoris and after percutaneous transluminal coronary angioplasty.

BACKGROUND: Inflammatory reactions have an important part in atherosclerosis. Smooth muscle cells, endothelial cells, monocytes, and T lymphocytes are actively involved. The purpose of this study was to assess whether T lymphocytes are activated in patients with stable angina pectoris who are candidates for a percutaneous transluminal coronary angioplasty (PTCA) and the influence of PTCA on this process. METHODS AND RESULTS: Twenty-four patients participated in the study. All were 40- to 60-year-old men, and all but one underwent successful PTCA. Blood samples were taken 1 day before PTCA and 1 week, 1 month, and 2 months after. Two groups of patients were detected: group A, 11 patients who had high levels of soluble interleukin-2 receptor (sIL-2R) before PTCA that decreased toward normal during the follow-up period in most of them; and group B, 13 patients who did not have elevated sIL-2R levels before PTCA and in whom sIL-2R levels did not change after the procedure. Group C consisted of 15 healthy men whose sIL-2R levels were in the normal range (control subjects). CONCLUSIONS: (1) T lymphocytes are activated in stable angina patients. (2) The level of sIL-2R can be a reliable laboratory marker for follow-up of patients after PTCA, especially those with high sIL-2R levels before the procedure.

Adult↗
PubMed1995

Helicobacter pylori infection and gastric metaplasia in the duodenum in China.

Biopsy specimens from antral and duodenal mucosa were obtained from 64 patients with active duodenal ulcer and from 78 with nonulcer dyspepsia. Gastric metaplasia in the duodenal bulb was more frequent in patients with duodenal ulcer (82.5%) than in patients with dyspepsia and duodenitis (53.1%) or in patients with dyspepsia without duodenitis (34.5%). Helicobacter pylori infection in the duodenal bulb was found more often in patients with moderate to severe gastric metaplasia (62.3%) than in patients with mild gastric metaplasia (20%). Therefore, patients from a developing country, China, showed the same relationship between duodenitis, gastric metaplasia, duodenal colonization with H. pylori, and duodenal ulcer previously demonstrated in developed countries.

Adolescent↗
PubMed1995

Magnetic resonance imaging may be an asset to diagnose and classify fluoroquinolone-associated Achilles tendinitis.

The aim of this study was to document the accuracy of magnetic resonance imaging (MRI) during fluoroquinolone-associated Achilles tendinitis. Fourteen Achilles tendons were examined by MRI (T1 and T2 or T2*-weighted sequences) in nine patients with typical tendinopathy (13 cases of tendinitis and 1 rupture) during fluoroquinolone therapy. Tendinous involvement was classified according to the prominence of intra- or peritendinous changes. The most typical feature was the presence of intratendinous changes, longitudinal or transversal, detected on T1 or T2-weighted sequences. Peritendinitis was most visible in two cases and nodular involvement in three cases. It was concluded that MRI appears a helpful and accurate method in identifying and classifying such iatrogenic tendinitis. In addition, MRI indicates orthopedic management when detecting risk of rupture.

Achilles Tendon↗
PubMed1995

[Value of calculation of the kappa coefficient in the evaluation of an imaging method].

Radiologists are often confronted to the choice of the most appropriate statistic tool for evaluating diagnostic imaging methods. Using a radiological literature example, the Kappa agreement test is herein described and its applications are determined. Although widely performed to determine the inter-rater agreement, this test is also suited for the confrontation of two or more diagnostic imaging methods applied on the same subjects and providing categorical data. It procures the degree of agreement between the different methods.

Angiography↗