Angiographic evaluation of vascular changes in ulcerative colitis

Review on novel targeted enzyme drug delivery systems: enzymosomes

The goal of this review is to present enzymosomes as an innovative means for site-specific drug delivery. Enzymosomes make use of an enzyme's special characteristics, such as its capacity to accelerate the reaction rate and bind to a particular substrate at a regulated rate. Enzymosomes are created when an enzyme forms a covalent linkage with a liposome or lipid vesicle surface. To construct enzymosomes with specialized activities, enzymes are linked using acylation, direct conjugation, physical adsorption, and encapsulation techniques. By reducing the negative side effects of earlier treatment techniques and exhibiting efficient medication release, these cutting-edge drug delivery systems improve long-term sickness treatments. They could be a good substitute for antiplatelet medication, gout treatment, and other traditional medicines. Recently developed supramolecular vesicular delivery systems called enzymosomes have the potential to improve drug targeting, physicochemical characteristics, and ultimately bioavailability in the pharmaceutical industry. Enzymosomes have advantages over narrow-therapeutic index pharmaceuticals as focusing on their site of action enhances both their pharmacodynamic and pharmacokinetic profiles. Additionally, it reduces changes in normal enzymatic activity, which enhances the half-life of an enzyme and accomplishes enzyme activity on specific locations.

(Re)Appraising Remission in Ulcerative Colitis

As the therapeutic targets in ulcerative colitis (UC) shift from control of symptoms to mucosal healing and prevention of disease complications like disability, colectomy, and cancer, the definition of remission has evolved. The current definition of clinical remission is variable and is determined by the clinical context in which it is being used. This results in skepticism and uncertainty about the true meaning of the term "clinical remission." In this review, the authors reexamine the definition of clinical remission and propose a novel approach to define remission in UC.

What Does Disease Progression Look Like in Ulcerative Colitis, and How Might It Be Prevented?

Ulcerative colitis (UC) has been characterized by inflammation limited to the mucosa. Although sustained and durable remission has been associated with mucosal healing, the recurrent phenomenon of persistent clinical disease activity despite mucosal healing has been observed in clinical practice and across pivotal trials. Over time, UC appears to confer an increased risk of progression, defined as changes of disease phenotype; adverse transmural effects on the bowel wall; increased risk of neoplasia development; worsening colorectal function; and increased risk of colectomy, hospitalizations, and other extraintestinal comorbidities. Although the treatment paradigm for Crohn's disease has shifted toward early aggressive intervention to prevent disease progression and irreversible bowel damage, such urgency in efforts to halt disease progression in UC have been largely overlooked. This review summarizes the multiple facets of UC contributing to a modified perception of the disease as a progressive one. We propose further study of the natural history and priorities for further treatment goals that include these considerations.

Hyperbaric oxygen therapy does not improve the effects of standardized treatment in a severe attack of ulcerative colitis: a prospective randomized study

BACKGROUND AND AIMS

Complementary therapy options are needed in the treatment of active ulcerative colitis (UC). Hyperbaric oxygen therapy (HBOT) has been shown to have positive effects in experimental models of colitis and perianal Crohn's disease.

METHODS

In the present prospective randomized open-label study, HBOT in addition to conventional medical treatment was compared with conventional treatment alone. The primary objective in this study was improved clinical outcome evaluated by Mayo score, laboratory tests and fecal weight. The secondary objectives were improvement in health-related quality of life, avoidance of colectomy and evaluation of HBOT safety.

RESULTS

The authors found no statistically significant differences between the treatment groups in any of the assessed variables.

CONCLUSION

The study results do not support the use of HBOT as a treatment option in a severe attack of UC.

Intra-arterial steroid-injection therapy for steroid-refractory acute graft-versus-host disease with the evaluation of angiography

We treated three patients with steroid-refractory acute graft-versus-host disease (aGVHD) with intra-arterial steroid-injection therapy (IAST). Two patients with gut aGVHD received IAST into both superior and inferior mesenteric arteries, while one patient with liver aGVHD received IAST into the proper hepatic artery. The volume of stools and the bilirubin level improved soon after IAST. Angiography of the superior and inferior mesenteric arteries was performed in the two patients with steroid-refractory gut aGVHD, and identical abnormal findings were obtained. IAST might be an earlier option for steroid-refractory aGVHD.

Immunological basis of inflammatory bowel disease: role of the microcirculation

Inflammatory bowel disease (IBD) is a chronic inflammatory condition of the intestine and/or colon of unknown etiology in which patients suffer from severe diarrhea, rectal bleeding, abdominal pain, fever, and weight loss. Active episodes of IBD are characterized by vasodilation, venocongestion, edema, infiltration of large numbers of inflammatory cells, and erosions and ulcerations of the bowel. It is becoming increasingly apparent that chronic gut inflammation may result from a dysregulated immune response toward components of the normal intestinal flora, resulting in a sustained overproduction of proinflammatory cytokines and mediators. Many of these Th1 and macrophage-derived cytokines and lipid metabolites are known to activate microvascular endothelial cells, thereby promoting leukocyte recruitment into the intestinal interstitium. This review discusses the basic immune mechanisms involved in the regulation of inflammatory responses in the gut and describes how a breakdown in this protective response initiates chronic gut inflammation.

Is proximal demarcation of ulcerative colitis determined by the territory of the inferior mesenteric artery?

The sharp demarcation between diseased and normal mucosa often observed in ulcerative colitis remains unexplained by current hypotheses of disease pathogenesis. To investigate whether this demarcation occurs at the watershed of vascular territories, the colonic arterial anatomy of 10 patients with ulcerative colitis was studied by in-vitro angiography and macroscopic and histological examination of total colectomy specimens. Of the 10 perfusion-fixed colectomy specimens studied, 7 had pancolitis associated with a complete marginal artery (Arteria marginalis coli) that spanned the entire length of the large bowel. 3 specimens had sharply demarcated disease in which the marginal artery arose from the inferior mesenteric artery and ended abruptly at the point of mucosal demarcation. The colon proximal to this point was histologically normal. These findings suggest that the proximal extent of colitis is determined by the limit of the marginal artery. We suggest that some characteristic of the mucosal microvasculature in the territory of the inferior mesenteric artery, possibly embryological in origin, predisposes the dependent colon to develop ulcerative colitis.

Faecal clearance of alpha 1-antitrypsin reflects disease activity and correlates with rapid turnover proteins in chronic inflammatory bowel disease

Faecal clearance of alpha 1-antitrypsin was measured in patients with ulcerative colitis and Crohn's disease and compared with disease activity and markers of protein-calorie malnutrition. Patients with active ulcerative colitis and Crohn's disease showed elevated clearance of alpha 1-antitrypsin and clearance declined in most patients with induction of remission. However, even with inactive disease, elevated protein loss persisted in some patients, presumably reflecting residual inflammation in the intestinal mucosa. There was a significant correlation between clearance of alpha 1-antitrypsin and serum levels of retinol-binding protein and transferrin in patients with ulcerative colitis and with retinol-binding protein in patients with Crohn's disease. Clearance of alpha 1-antitrypsin reflects disease activity in inflammatory bowel disease and correlates with serum levels of rapid-turnover proteins such as retinol-binding protein and transferrin, which are markers for the presence of protein-calorie malnutrition.