Search

Objectives: The relative contribution of the local vs. peripheral inflammation to the atherothrombotic processes is unknown. We compared the inflammatory status of the immune cells of the carotid plaque with similar cells in peripheral circulation of patients with advanced carotid disease (PCDs)., Methods: Mononuclear cells (MNCs) were extracted from carotid endarterectomy (CEA) samples by enzymatic digestion and subsequent magnetic cell sorting. The cell surface antigenic expressions, and mRNA expression levels were compared between CEA MNCs and peripheral MNCs, using flow cytometry and RT-PCR techniques., Results: The percentages of resting MNCs were lower, and activated MNCs, particularly monocytes, were higher in the CEAMNCs, as compared to the peripheral MNCs. The percentages of activated T cells and B cells were higher in the peripheral MNCs of PCDs, than in healthy controls (HCs), but the percentages of activated monocytes did not differ between the two groups. The expression levels of both pro-inflammatory/pro-thrombotic (P(38), JNKB-1, Egr-1 PAI-1, MCP-1, TF, MMP-9, HMGB-1, TNF-α, mTOR) and anti-inflammatory (PPAR-γ, TGF-β) mediators were significantly higher in the CEA MNCs as compared to the peripheral MNCs. Furthermore, MMP-9 and PPAR-γ expression levels were higher in the peripheral MNCs of PCDs than HCs., Conclusion: The inflammatory status is higher in the immune cells of the carotid plaque, as compared to those cells in the peripheral blood. The altered expression levels of both pro-inflammatory/pro-thrombotic and anti-inflammatory mediators in the milieu of the plaque suggest that the balance between these various mediators may play a key role in carotid disease progression., (Published by Elsevier Ireland Ltd.)

As research techniques and biotechnology advance, the risk for potential bioterrorism increases due to the ease of creating or modifying virulent pathogenic microorganisms. In addition, the destruction of natural habitats to a range of animals and microbial species that are normally sequestered in these areas may bring forth new diseases to humans.

Many attempts have been made to inhibit viral and neoplastic diseases by targeting the RNA system. The pathophysiologic significance of the microRNA system and the therapeutic potential of its manipulation are discussed. Studies of double-stranded RNA derivatives are reviewed. The therapeutic potential of one of these compounds, polyI:MPC, is emphasized. Studies of other related antiviral and antineoplastic agents are discussed, including 2'-deoxyoligocytidilates and telomerase inhibitors.

Double-stranded RNAs induce interferons and cause the development of antiviral and antiproliferative activities. Antiviral activity is related to the production of interferons and other proteins that stimulate various immunologic activities, which appear to contribute to their overall antiproliferative activity. The most active double-stranded RNA, polyI:polyC, was shown to be too toxic for therapeutic use. We conducted selective thiolation of the polyC strand at the five position of the cytosine bases, generating a partially thiolated polyC (MPC) which after annealing with a complimentary unmodified polyI, gave the thiolated double-stranded RNA, pI:MPC. We have explored antiviral and antiproliferative activities at various levels of thiolation and found that optimal responses can be obtained at 7.4% level of thiolation. This compound deserves further study of antiviral and antiproliferative responses in vivo, and eventually clinical exploration. Earlier studies have shown that this and related compounds are active against HIV-1, in human cells, and against DNA polymerases of DNA and RNA tumor viruses.

Extract: Interferons alpha, beta and gamma are a group of structurally and functionally related proteins, produced in response to viruses or double-stranded RNA and defined by their ability to establish an antiviral state in cells. They were originally discovered by Isaacs and Lindenmann (1957). Since their original discovery, several interferon genes and proteins have been identified. Their mechanisms of action were studied and in addition to the antiviral activity, other biological activities were also uncovered including inhibition of cell proliferation and immunomodulation. Human interferon-alpha is a family of at least 23 polypeptides coded by several related genes. The various interferons exhibit a high level of species specificity with some exceptions. For example, there is a high level of activity of human interferon-alpha subtypes on bovine cells. Interferons have been used for the treatment of certain viral infections, multiple sclerosis, certain cancers including hematologic malignancies and Acquired Immune Deficiency Syndrome (AIDS)-related cancerous complications.

Infectious diseases are the major causes of death and morbidity in underdeveloped countries, particularly in children. Increasing evidence suggests that malnutrition-both Protein-Energy type Malnutrition (PEM) and essential micronutrient (vitamins, trace minerals, essential amino acids, polyunsaturated fatty acids) type-is the underlying reason for increased susceptibility to infections. On the other hand, certain infectious diseases also cause malnutrition, which results in a vicious cycle. Before its viral origin was known, acquired immunodeficiency syndrome (AIDS) had been termed the thin disease because cachexia was AIDS' main clinical manifestation. The relationship between infection and malnutrition is well documented in the literature. Our experience supports this. Preventive and therapeutic measures are suggested.

Interferon (IFN) resistance is an important factor in the pathophysiology of neoplastic disorders, certain viral infections (e.g., AIDS), and autoimmune diseases (e.g., lupus erythematosus and Wegner's granulomatosis). In addition, in some of these disorders, there is also decreased ability to produce IFNs. The capacity of viruses and neoplastic processes to interfere with the IFN system are thought to represent a "virus-against-host" or "cancer-against-host" defense mechanism. Four resistance factors have been identified: 1) release of free IFN-alpha/beta type 1 receptors into the circulation that, at appropriate concentrations, capture and inactivate IFNs; 2) a new IFN inhibitory protein has been isolated and its chemical structure is under study; 3) prostaglandin E2, which is produced by certain tumor cells, inhibits IFN production; and 4) high levels of cAMP phosphodiesterases present, for example in certain tumor cells, reduces cAMP, an important second messenger in IFN synthesis. Studies are under way to reverse these inhibitory effects and to increase endogenous interferon production.

In previous studies, experimental splenosis was produced in normal rodents and in animals following splenectomy. Splenosis was more in splenectomised than in normal animals. In the present study, in animals into whom splenic fragments were implanted subcutaneously, there were less peritoneal splenic growth areas than in controls. The hypothesis is presented that there is a population size feedback control regulatory mechanism operating in splenic growth and regeneration. If such regulators are present in the circulation, administration of normal plasma should inhibit splenosis and this may serve as a model to isolate such regulators. This was not the case in these experiments.

This is a brief review on studies of attacking HIV through a new angle. In previous studies, we have found that many patients with AIDS are resistant to interferon (IFN) therapy, and some develop resistance during therapy. Four factors were found to be responsible for the resistance of untreated patients: (a). release of free-circulating IFN-alpha/beta type 1 receptors, (b). a newly detected IFN inhibitory protein, (c). high prostaglandin E2, and (d). high levels of cAMP phosphodiesterases, particularly in AIDS-related neoplasms. This may interfere with intrinsic disease resistance and with the efficacy of IFN therapy. In an attempt to overcome this resistance, new compounds were synthesized which increase endogenous production of alpha, beta and gamma IFNs, have anti-template activity against DNA and RNA polymerases, inhibit reverse transcriptases and activates IFN-induced double-stranded RNA (dsRNA)-dependent protein kinase. It is expected that planned nonhuman primate and clinical studies will support preliminary findings. Preliminary in vitro and animal studies suggest that these new compounds may be effective against HIV, including multi-drug resistant strains.

Background: Many viral and neoplastic diseases are resistant to interferon-alpha/beta (IFN-alpha/beta) therapy or develop resistance during the course of IFN treatment. In patients with viral diseases, the authors identified four IFN inhibitors, of which the most important, most likely is a free IFN receptor of type 1 appearing in the circulation that captures and neutralizes IFN-alpha/beta., Methods: Ninety-one cancer patients and 25 healthy individuals were studied. Free circulating IFN receptor-alpha/beta type 1 was studied. The patients were ages 35-75 years. The diagnoses were 24 cases of colon carcinoma, 7 cases of prostate carcinoma, 16 cases of breast carcinoma, 8 cases of ovarian carcinoma, 9 cases of uterine carcinoma, 5 cases of lung carcinoma, 3 cases of astrocytoma, 4 cases of transitional cell carcinoma of the bladder, 1 case of osteosarcoma, 3 cases of multiple myeloma, 4 cases of Hodgkin disease, 2 cases of non-Hodgkin lymphoma, 3 cases of myelodysplastic syndrome, and 2 disseminated tumors of unknown origin., Results: All patients were found to have increased free IFN receptor-alpha/beta type 1 in the circulation, with the highest levels reported in patients with adenocarcinoma., Conclusions: High IFN inhibitory activity in patients with cancer may be a significant factor in their increased susceptibility to progressive disease, infectious complications, and resistance to IFN therapy. Ongoing studies are being performed with the objective of overcoming this inhibitory activity., (Copyright 2003 American Cancer Society.)

Background: Desmoid tumour (DT) is an uncommon locally invasive non-metastasizing neoplastic lesion. The aetiology of this tumour is unknown and its treatment is controversial. Twelve cases of DT are presented and the literature is reviewed., Methods: Twelve cases of DT treated at our institution during a 3.5-year period are analysed and the literature reviewed. Ten patients were referred with a primary tumour, one with local recurrence and one patient with a second primary desmoid tumour. One patient had multiple mesenteric DT (familial adenomatous polyposis coli-FAP), and in the remaining 11 patients the tumour was located in the abdominal wall in four, at an extremity in three, in the upper back in two patients, in the pelvis in one and retroperitoneally in one., Results: The largest mesenteric DT was marginally excised en bloc with total jejunectomy. In the remaining 11 DT, complete excision to microscopically tumour-free margins was possible in nine cases and to microscopically involved margins in two cases. At a mean follow-up of 22 months (range 7-38 months), one patient was alive with stable disease (Gardner's syndrome), 10 patients were alive and free of recurrence and one patient (9%) developed local recurrence which was re-excised-she is disease-free 10 months later., Conclusions: Complete excision is the main modality of treatment for primary and recurrent DT. This is feasible in most cases except for tumours involving the base of the bowel mesentery. Surgical resection alone achieved local control of the tumour in most of the patients in this series (92%).