Artificial intelligence-assisted colonoscopy to identify histologic remission and predict the outcomes of patients with ulcerative colitis: A systematic review

This systematic review evaluated the current status of AI-assisted colonoscopy to identify histologic remission and predict the clinical outcomes of patients with ulcerative colitis. The use of artificial intelligence (AI) has increased substantially across several medical fields, including gastrointestinal endoscopy. Evidence suggests that it may be helpful to predict histologic remission and relapse, which would be beneficial because current histological diagnosis is limited by the inconvenience of obtaining biopsies and the high cost and time-intensiveness of pathological diagnosis. MEDLINE and the Cochrane Central Register of Controlled Trials were searched for studies published between January 1, 2000, and October 31, 2023. Nine studies fulfilled the selection criteria and were included; five evaluated the prediction of histologic remission, two assessed the prediction of clinical outcomes, and two evaluated both. Seven were prospective observational or cohort studies, while two were retrospective observational studies. No randomized controlled trials were identified. AI-assisted colonoscopy demonstrated sensitivity between 65 %-98 % and specificity values of 80 %-97 % for identifying histologic remission. Furthermore, it was able to predict future relapse in patients with ulcerative colitis. However, several challenges and barriers still exist to its routine clinical application, which should be overcome before the true potential of AI-assisted colonoscopy can be fully realized.

Clinical outcomes of diverticular disease in young adults: results from a tertiary referral center

Introduction

Diverticular disease (DD), commonly associated with the elderly, is becoming more prevalent among younger individuals. This retrospective study aimed to evaluate the differences in the natural history and outcomes between young and old patients with DD.

Methods

Adult patients with DD diagnosed between 2010 and 2022 at an Italian tertiary referral center were enrolled, and their demographic and clinical data were retrieved. The patients were categorized as young or old based on the 25th percentile of the population's age at diagnosis. Univariate and multivariate analyses were performed to assess the association between the collected variables and the age of disease presentation. Additionally, survival analyses were conducted to evaluate the association between the age of diagnosis and clinical outcomes at follow-up, including disease recurrence, hospital access, surgery, and death.

Results

A total of 220 DD patients (with a median age of 66 years, IQR 55-74, and a female-to-male ratio of 1.4:1) were included in the study, comprising 54 patients receiving a diagnosis before the age of 49 years (young DD patients) and 166 patients diagnosed after the age of 49 years (old DD patients). Male sex (57 vs. 36%, p < 0.01), smoking (38 vs. 14%, p < 0.01), and alcohol consumption (54 vs. 38%) were highly prevalent in young patients. The complications at the time of diagnosis, particularly abscesses and free perforations, occurred more frequently in younger patients (p = 0.04). Moreover, young DD patients experienced a higher rate of hospitalization and surgical intervention (p = 0.01 and p = 0.04, respectively) over a median follow-up period of 5 years.

Conclusion

Preventive strategies and prompt diagnosis are crucial in young patients with DD for achieving better disease outcomes and preventing complications.

Recent advances in intestinal fibrosis

Despite many progresses have been made in the treatment of inflammatory bowel disease, especially due to the increasing number of effective therapies, the development of tissue fibrosis is a very common occurrence along the natural history of this condition. To a certain extent, fibrogenesis is a physiological and necessary process in all those conditions characterised by chronic inflammation. However, the excessive deposition of extracellular matrix within the bowel wall will end up in the formation of strictures, with the consequent need for surgery. A number of mechanisms have been described in this process, but some of them are not yet clear. For sure, the main trigger is the presence of a persistent inflammatory status within the mucosa, which in turn favours the occurrence of a pro-fibrogenic environment. Among the main key players, myofibroblasts, fibroblasts, immune cells, growth factors and cytokines must be mentioned. Although there are no available therapies able to target fibrosis, the only way to prevent it is by controlling inflammation. In this review, we summarize the state of art of the mechanisms involved in gut fibrogenesis, how to diagnose it, and which potential targets could be druggable to tackle fibrosis.

Present and future of endoscopy precision for inflammatory bowel disease

Several advanced imaging techniques are now available for endoscopists managing inflammatory bowel disease (IBD) patients. These tools, including dye-based and virtual chromoendoscopy, probe-based confocal laser endomicroscopy and endocytoscopy, are increasingly innovative applications in clinical practice. They allow for a more in-depth and refined evaluation of the mucosal and vascular bowel surface, getting closer to histology. They have demonstrated a remarkable ability in assessing intestinal inflammation, histologic remission, and predicting relapse and favorable long-term outcomes. In addition, the future application of molecular endoscopy to predict biological drug responses has yielded preliminary but encouraging results. Furthermore, these techniques are crucial in detecting and characterizing IBD-related dysplasia, assisting endoscopic mucosal resection and submucosal dissection towards a surgery-sparing approach. Artificial intelligence (AI) holds great potential in this promising landscape, as it can provide an objective and reproducible assessment of inflammation and dysplasia. Moreover, it can improve the prediction of outcomes and aid in subsequent therapeutic decision-making. This review aims to summarize the promising role of state-of-the-art advanced endoscopic techniques and related AI-enabled models for managing IBD, paving the way for precision medicine.

Diagnostic delay in symptomatic uncomplicated diverticular disease: an Italian tertiary referral centre study

The magnitude of the diagnostic delay of symptomatic uncomplicated diverticular disease (SUDD) is unknown; we aimed to evaluate SUDD diagnostic delay and its risk factors. SUDD patients diagnosed at a tertiary referral centre were retrospectively enrolled (2010-2022). Demographic and clinical data were retrieved. Overall, patient-, and physician-dependant diagnostic delays were assessed. Univariate and multivariate analyses were fitted to identify risk factors for diagnostic delay. Overall, 70 SUDD patients (median age 65 years, IQR 52-74; F:M ratio = 1.6:1) were assessed. The median overall diagnostic delay was 7 months (IQR 2-24), patient-dependant delay was 3 months (IQR 0-15), and physician-dependant delay was 1 month (IQR 0-6). Further, 25% of patients were misdiagnosed with irritable bowel syndrome (IBS). At multivariate analysis, previous misdiagnosis was a significant risk factor for overall and physician-dependant diagnostic delay (OR 9.99, p = 0.01, and OR 6.46, p = 0.02, respectively). Also, a high educational level (> 13 years) was associated with a greater overall diagnostic delay (OR 8.74 p = 0.02), while previous abdominal surgery was significantly associated to reduced physician-dependant diagnostic delay (OR 0.19 p = 0.04). To conclude, SUDD may be diagnosed late, IBS being the most frequent misdiagnosis. Timely diagnosis is crucial to tackle the burden of SUDD on patients and healthcare.

Role of mucosal immunity and epithelial-vascular barrier in modulating gut homeostasis

The intestinal mucosa represents the most extensive human barrier having a defense function against microbial and food antigens. This barrier is represented externally by a mucus layer, consisting mainly of mucins, antimicrobial peptides, and secretory immunoglobulin A (sIgA), which serves as the first interaction with the intestinal microbiota. Below is placed the epithelial monolayer, comprising enterocytes and specialized cells, such as goblet cells, Paneth cells, enterochromaffin cells, and others, each with a specific protective, endocrine, or immune function. This layer interacts with both the luminal environment and the underlying lamina propria, where mucosal immunity processes primarily take place. Specifically, the interaction between the microbiota and an intact mucosal barrier results in the activation of tolerogenic processes, mainly mediated by FOXP3+ regulatory T cells, underlying intestinal homeostasis. Conversely, the impairment of the mucosal barrier function, the alteration of the normal luminal microbiota composition (dysbiosis), or the imbalance between pro- and anti-inflammatory mucosal factors may result in inflammation and disease. Another crucial component of the intestinal barrier is the gut-vascular barrier, formed by endothelial cells, pericytes, and glial cells, which regulates the passage of molecules into the bloodstream. The aim of this review is to examine the various components of the intestinal barrier, assessing their interaction with the mucosal immune system, and focus on the immunological processes underlying homeostasis or inflammation.

Next-Generation Endoscopy in Inflammatory Bowel Disease

Endoscopic healing is recognized as a primary treatment goal in Inflammatory Bowel Disease (IBD). However, endoscopic remission may not reflect histological remission, which is crucial to achieving favorable long-term outcomes. The development of new advanced techniques has revolutionized the field of IBD assessment and management. These tools can accurately assess vascular and mucosal features, drawing endoscopy closer to histology. Moreover, they can enhance the detection and characterization of IBD-related dysplasia. Given the persistent challenge of interobserver variability, a more standardized approach to endoscopy is warranted, and the integration of artificial intelligence (AI) holds promise for addressing this limitation. Additionally, although molecular endoscopy is still in its infancy, it is a promising tool to forecast response to therapy. This review provides an overview of advanced endoscopic techniques, including dye-based and dye-less chromoendoscopy, and in vivo histological examinations with probe-based confocal laser endomicroscopy and endocytoscopy. The remarkable contribution of these tools to IBD management, especially when integrated with AI, is discussed. Specific attention is given to their role in improving disease assessment, detection, and characterization of IBD-associated lesions, and predicting disease-related outcomes.

Clinical and Histopathological Features of an Italian Monocentric Series of Primary Small Bowel T-Cell Lymphomas

The gastrointestinal (GI) tract is the most common extranodal site of occurrence of non-Hodgkin lymphomas. Most GI lymphomas are of B-cell lineage, while T-cell lymphomas are less frequent. The aim of our retrospective study was to depict the clinical-pathological profile of a series of patients affected by intestinal T-cell lymphomas (ITCL) and possibly define hallmarks of these neoplasms. A total of 28 patients were included: 17 enteropathy-associated T-cell lymphomas (EATL), 5 monomorphic epitheliotropic T-cell lymphomas (MEITL), 3 indolent T-cell lymphoproliferative disorders of the gastrointestinal tract (ITCLDGT), and 3 intestinal T-cell lymphomas not otherwise specified (ITCL-NOS). Celiac disease (CD) was diagnosed in around 70% of cases. Diagnosis of EATL showed a significant correlation with CD30 expression, whereas MEITL with angiotropism and CD56 positivity. ITCLDGT cases showed plasma cells infiltration. Peripheral lymphocytosis, the absence of a previous diagnosis of CD, an advanced Lugano clinical stage, and the histological subtype ITCL-NOS were significantly associated with worse survival at multivariate analysis. Our findings about the epidemiological, clinical, and histopathological features of ITCL were in line with the current knowledge. Reliable prognostic tools for these neoplasms are still lacking but according to our results lymphocytosis, diagnosis of CD, Lugano clinical stage, and histological subtype should be considered for patient stratification.

Inflammation-Driven Colorectal Cancer Associated with Colitis: From Pathogenesis to Changing Therapy

Patients affected by inflammatory bowel disease (IBD) have a two-fold higher risk of developing colorectal cancer (CRC) than the general population. IBD-related CRC follows a different genetic and molecular pathogenic pathway than sporadic CRC and can be considered a complication of chronic intestinal inflammation. Since inflammation is recognised as an independent risk factor for neoplastic progression, clinicians strive to modulate and control disease, often using potent therapy agents to achieve mucosal healing and decrease the risk of colorectal cancer in IBD patients. Improved therapeutic control of inflammation, combined with endoscopic advances and early detection of pre-cancerous lesions through surveillance programs, explains the lower incidence rate of IBD-related CRC. In addition, current research is increasingly focused on translating emerging and advanced knowledge in microbiome and metagenomics into personalised, early, and non-invasive CRC screening tools that guide organ-sparing therapy in IBD patients. This review aims to summarise the existing literature on IBD-associated CRC, focusing on new insights into the alteration of the intestinal barrier and the interactions with the gut microbiome as the initial promoter. In addition, the role of OMIC techniques for precision medicine and the impact of the available IBD therapeutic armamentarium on the evolution to CRC will be discussed.

Glutathione: Pharmacological aspects and implications for clinical use in non-alcoholic fatty liver disease

Glutathione is a tripeptide synthesized at cytosolic level, that exists in cells in a reduced form (thiol-reduced-GSH-) and in an oxidized form (disulfide-oxidized). The antioxidant function of GSH has led to speculation about its therapeutic role in numerous chronic diseases characterized by altered redox balance and reduced GSH levels, including, for instance, neurodegenerative disorders, cancer, and chronic liver diseases. Among these latter, non-alcoholic fatty liver disease (NAFLD), characterized by lipid accumulation in hepatocytes, in the absence of alcohol abuse or other steatogenic factors, is one of the most prevalent. The umbrella term NAFLD includes the pure liver fat accumulation, the so-called hepatic steatosis or non-alcoholic fatty liver, and the progressive form with inflammation, also known as non-alcoholic steatohepatitis, which is related to the increase in oxidative stress and reactive oxygen species, eventually leading to liver fibrosis. Although the pathogenetic role of oxidative stress in these diseases is well established, there is still limited evidence on the therapeutic role of GSH in such conditions. Hence, the aim of this review is to depict the current molecular and pharmacological knowledge on glutathione, focusing on the available studies related to its therapeutic activity in NAFLD.

Diagnostic delay in adult coeliac disease: An Italian multicentre study

BACKGROUND

There are few data regarding the diagnostic delay and its predisposing factors in coeliac disease (CD).

AIMS

To investigate the overall, the patient-dependant, and the physician-dependant diagnostic delays in CD.

METHODS

CD adult patients were retrospectively enroled at 19 Italian CD outpatient clinics (2011-2021). Overall, patient-dependant, and physician-dependant diagnostic delays were assessed. Extreme diagnostic, i.e., lying above the third quartile of our population, was also analysed. Multivariable regression models for factors affecting the delay were fitted.

RESULTS

Overall, 2362 CD patients (median age at diagnosis 38 years, IQR 27-46; M:F ratio=1:3) were included. The median overall diagnostic delay was 8 months (IQR 5-14), while patient- and physician-dependant delays were 3 (IQR 2-6) and 4 (IQR 2-6) months, respectively. Previous misdiagnosis was associated with greater physician-dependant (1.076, p = 0.005) and overall (0.659, p = 0.001) diagnostic delays. Neurological symptoms (odds ratio 2.311, p = 0.005) and a previous misdiagnosis (coefficient 9.807, p = 0.000) were associated with a greater extreme physician-dependant delay. Gastrointestinal symptoms (OR 1.880, p = 0.004), neurological symptoms (OR 2.313, p = 0.042), and previous misdiagnosis (OR 4.265, p = 0.000) were associated with increased extreme overall diagnostic delay.

CONCLUSION

We identified some factors that hamper CD diagnosis. A proper screening strategy for CD should be implemented.

Case Report: A rare case of small bowel obstruction secondary to plasma cell myeloma

Gastrointestinal (GI) involvement of plasma cell neoplasms is extremely rare. Herein, we describe the case of a 74-year-old Caucasian woman who came to our attention with abdominal pain, food vomiting, and weight loss of 10 kg over 1 year. A computed tomography scan of the abdomen revealed circumferential thickening of terminal ileum, for which the patient underwent an urgent 20-cm-long ileal resection. Histopathological and immunophenotypic analysis revealed a plasma cell neoplasm of the ileum. Subsequent investigations found a serum monoclonal immunoglobulin A component, an osteolytic lesion of the left jaw, and a clonal bone marrow plasma cell infiltrate carrying 1q21 amplification. Given the final diagnosis of plasma cell myeloma (PCM), the patient underwent a VMD (bortezomib, melphalan, and dexamethasone) chemotherapy regimen, achieving a complete remission after a 12-month treatment. For disease relapse, two further chemotherapy regimens were later attempted. At the last follow-up 4 years after the diagnosis, the patient is still alive. This case draws attention to the extramedullary presentation of plasma cell neoplasms, even if rare, as a prompt diagnosis seems to result in a better prognosis. In addition, it highlights the relevance of a multidisciplinary approach, involving gastroenterologists, hematologists, and pathologists, to the diagnosis and management of these neoplasms.

Impact of COVID-19 in immunosuppressive drug-naïve autoimmune disorders: Autoimmune gastritis, celiac disease, type 1 diabetes, and autoimmune thyroid disease

Few conflicting data are currently available on the risk of SARS-CoV-2 infection in patients with autoimmune disorders. The studies performed so far are influenced, in most cases, by the treatment with immunosuppressive drugs, making it difficult to ascertain the burden of autoimmunity per se. For this reason, herein we assessed the susceptibility to COVID-19 in immunosuppressive drug-naïve patients with autoimmune diseases, such as autoimmune gastritis (AIG), celiac disease (CD), type 1 diabetes (T1D), and autoimmune thyroid disease (AITD). Telephone interviews were conducted on 400 patients-100 for each group-in May 2021 by looking at the positivity of molecular nasopharyngeal swabs and/or serology for SARS-CoV-2, the need for hospitalization, the outcome, and the vaccination status. Overall, a positive COVID-19 test was reported in 33 patients (8.2%), comparable with that of the Lombardy general population (8.2%). In particular, seven patients with AIG, 9 with CD, 8 with T1D, and 9 with AITD experienced COVID-19. Only three patients required hospitalization, none died, and 235 (58.7%) were vaccinated, 43 with AIG, 47 with CD, 91 with T1D, and 54 with AITD. These results seem to suggest that autoimmunity per se does not increase the susceptibility to COVID-19. Also, COVID-19 seems to be mild in these patients, as indicated by the low hospitalization rates and adverse outcomes, although further studies are needed to better clarify this issue.

Allergic manifestations in autoimmune gastrointestinal disorders

Allergic disorders target a young population, are increasing in both incidence and prevalence and are associated with significant disease burden. They result from the complex interplay between (epi)genetic and environmental factors, resulting in a Th2 inflammatory process targeting the epithelium of the respiratory tract (allergic rhinitis and asthma), skin (atopic dermatitis), and gastrointestinal tract (food allergy). Although the exact pathogenic mechanisms remain elusive, an altered immune system response in the gut is increasingly recognized as a relevant step. Allergic and gastrointestinal autoimmune disorders share several epidemiological, pathogenic and risk factors and several treatment modalities. Here we revise the current literature and show that allergic disorders are highly prevalent in gastrointestinal autoimmune diseases, including celiac disease, inflammatory bowel disease, autoimmune pancreatitis, and autoimmune cholangiopathies. No data are available for some autoimmune diseases, such as autoimmune gastritis and autoimmune enteropathy. To ensure the comprehensive care of patients with autoimmune gastrointestinal disorders, along with disease-specific factors, the presence of allergic disorders should be evaluated and treated when present, possibly targeting shared molecular pathways. Future studies are needed to define the exact pathogenic mechanisms underpinning the association between allergic and autoimmune diseases of the gastrointestinal tract.

Liver-spleen axis dysfunction in COVID-19

Coronavirus disease 2019 (COVID-19), caused by the novel severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2), is an acute infectious disease that spreads mainly through the respiratory route. Besides interstitial pneumonia, a number of other clinical manifestations were noticed in COVID-19 patients. In particular, liver and spleen dysfunctions have been described both as complications of COVID-19 and as potential predisposing factors for severe COVID-19. Liver damage is rather common in COVID-19 patients, and it is most likely multifactorial, caused by the direct insult of SARS-CoV-2 to the liver by the cytokine storm triggered by the virus, by the use of hepatotoxic drugs, and as a consequence of hypoxia. Although generally mild, liver impairment has been found to be associated with a higher rate of intensive care unit admission. A higher mortality rate was reported among chronic liver disease patients. Instead, spleen impairment in patients with COVID-19 has been poorly described. The main anatomical changes are the architectural derangement of the B cell compartment, white pulp atrophy, and reduction or absence of lymphoid follicles, while, from a functional point of view, the IgM memory B cell pool is markedly depleted. The outcome of COVID-19 in asplenic or hyposplenic patients is yet to be defined. In this review, we will summarise the current knowledge regarding the impact of SARS-CoV-2 on the liver and spleen function, as well as the outcome of patients with a pre-existent liver disease or defective spleen function.

Serum Markers of Refractoriness and Enteropathy-Associated T-Cell Lymphoma in Coeliac Disease

Simple Summary

Coeliac disease is a common chronic enteropathy that may lead to severe complications, including refractoriness (i.e., nonresponsiveness to a gluten-free diet) and enteropathy-associated T-cell lymphoma. In this study, we found that two serum markers, namely chromogranin A and β2-microglobuline, can predict these complications in patients with coeliac disease.

Abstract

The persistence or recurrence of symptoms in patients with coeliac disease (CD), despite a gluten-free diet (GFD), must prompt further work-up for excluding refractory CD (RCD). The aim of this study was to assess the accuracy of serum markers in predicting refractoriness in CD patients. This study included 72 patients affected by CD followed-up at our center, namely 49 uncomplicated CD before and after GFD and 23 RCD. Serum levels of chromogranin A (CgA) and β2-microglobuline were measured at baseline and at follow-up (median time of 13 months) in each group of patients. Cut-off points for each marker were estimated to differentiate RCD from uncomplicated CD patients. Serum levels of CgA and β2-microglobuline were significantly higher in patients with RCD compared to uncomplicated CD (p < 0.001), both at baseline and at follow-up, with no significant difference between RCD type 1 and type 2. The estimated cut-off point for CgA was 90.2 ng/mL (sensitivity 83%, specificity 100%), while for β2-microglobuline it was 696 mcg/L (sensitivity 100%, specificity of 100%). To conclude, CgA and β2-microglobuline could be useful serological markers of refractoriness in CD, with the ability to discriminate those patients who should undergo upper gastrointestinal endoscopy for making a definite diagnosis.

Impact of COVID-19 on liver function: results from an internal medicine unit in Northern Italy

Little is known regarding coronavirus disease 2019 (COVID-19) clinical spectrum in non-Asian populations. We herein describe the impact of COVID-19 on liver function in 100 COVID-19 consecutive patients (median age 70 years, range 25-97; 79 males) who were admitted to our internal medicine unit in March 2020. We retrospectively assessed liver function tests, taking into account demographic characteristics and clinical outcome. A patient was considered as having liver injury when alanine aminotransferase (ALT) was > 50 mU/ml, gamma-glutamyl transpeptidase (GGT) > 50 mU/ml, or total bilirubin > 1.1 mg/dl. Spearman correlation coefficient for laboratory data and bivariable analysis for mortality and/or need for intensive care were assessed. A minority of patients (18.6%) were obese, and most patients were non- or moderate-drinkers (88.5%). Liver function tests were altered in 62.4% of patients, and improved during follow-up. None of the seven patients with known chronic liver disease had liver decompensation. Only one patient developed acute liver failure. In patients with altered liver function tests, PaO2/FiO2 < 200 was associated with greater mortality and need for intensive care (HR 2.34, 95% CI 1.07-5.11, p = 0.033). To conclude, a high prevalence of altered liver function tests was noticed in Italian patients with COVID-19, and this was associated with worse outcomes when developing severe acute respiratory distress syndrome.

Recurrence of angina after ST-segment elevation myocardial infarction: the role of coronary microvascular obstruction

BACKGROUND

The recurrence of angina after percutaneous coronary intervention affects 20-35% of patients with stable coronary artery disease; however, few data are available in the setting of ST-segment elevation myocardial infarction. We evaluated the relation between coronary microvascular obstruction and the recurrence of angina at follow-up.

METHODS

We prospectively enrolled patients with ST-segment elevation myocardial infarction undergoing primary percutaneous coronary intervention. Microvascular obstruction was defined as thrombolysis in myocardial infarction flow less than 3 or 3 with myocardial blush grade less than 2. The primary endpoint was the recurrence of angina at follow-up. Moreover, angina status was evaluated by the Seattle angina questionnaire summary score (SAQSS). Therapy at follow-up and the occurrence of major adverse cardiovascular events were also collected.

RESULTS

We enrolled 200 patients. Microvascular obstruction occurred in 52 (26%) of them. Follow-up (mean time 25.17±9.28 months) was performed in all patients. Recurrent angina occurred in 31 (15.5%) patients, with a higher prevalence in patients with microvascular obstruction compared with patients without microvascular obstruction (13 (25.0%) vs. 18 (12.2%), P=0.008). Accordingly, SAQSS was lower and the need for two or more anti-anginal drugs was higher in patients with microvascular obstruction compared with patients without microvascular obstruction. At multiple linear regression analysis a history of previous acute coronary syndrome and the occurrence of microvascular obstruction were the only independent predictors of a worse SAQSS. Finally, the occurrence of major adverse cardiovascular events was higher in patients with microvascular obstruction compared with patients without microvascular obstruction.

CONCLUSIONS

The recurrence of angina in ST-segment elevation myocardial infarction patients treated with primary percutaneous coronary intervention is an important clinical issue. The occurrence of microvascular obstruction portends a worse angina status and is associated with the use of more anti-anginal drugs.

Endorectal sonographic appearances of rectal MALT lymphoma, its response to therapy, and local recurrence

Endorectal sonography may significantly help to evaluate rectal lymphoma. We report the sonographic findings in a case of rectal non-Hodgkin's MALT (mucosa-associated lymphoid tissue) lymphoma, including the monitoring of response to therapy and confirmation of recurrence, in a 45-year-old man. On endorectal sonography of the rectal wall, the mucosa was markedly thickened to 1.1 cm and was diffusely hypoechoic and risen into multiple polypoid folds. The submucosa and muscularis propria appeared normal. Multiple lymph nodes were visualized in the perirectal fat; they were homogeneously hypoechoic, were round or oval, and ranged from 1.0 cm to 2.6 cm. Endoscopic biopsies revealed a grade I non-Hodgkin's MALT lymphoma. Following chemotherapy, endorectal sonography showed that the surface of the rectal mucosa had a smoother appearance and near-normal thickness, but lymph nodes, although smaller, remained visible in the perirectal fat. Four months later, endorectal sonography demonstrated a local relapse of disease, with significant thickening of the rectal mucosa and multiple lymph nodes visible in the perirectal fat. Following high-dose chemotherapy for the recurrence, endorectal sonography demonstrated a near-normal appearance of the rectal mucosa.

Decline with age of the respiratory chain activity in human skeletal muscle

Mitochondrial respiratory systems have been screened in 63 orthopaedic patients of age ranging between 17 and 91 years. The results show a statistically significant definite decrease with ageing of mitochondrial respiratory activity with pyruvate plus malate, succinate and ascorbate plus TMPD. This pattern is associated with an equally significant decrease with age of the enzymatic activity of complex I, II and IV. No significant decrease with age is, on the contrary, observed in the mitochondrial content of cytochromes a+a3, and c+c1. Preliminary Western blot analysis indicates an altered polypeptide pattern in cytochrome c oxidase. This study provides evidence for a decline with age of mitochondrial respiratory activity in human skeletal muscle, affecting complex I, II and IV.

Human osteoclast-like cells recognize laminin via an RGD independent mechanism

Interactions between cells from human giant cell tumors of bone and the extracellular matrix protein laminin were studied. Cells were capable of recognizing this substratum via a RGD-independent mechanism. Recognition induces adhesion and spreading onto laminin. This protein triggered the release of cellular FN which in turn enhanced recruitment of the beta 1 chain-containing integrin receptor.

Long-term effects of eating sucrose on metabolic control of type 1 (insulin-dependent) diabetic outpatients

The aim of the study was to investigate the effects of regularly eating a moderate amount of sucrose (30 g/day) in 12 type 1 (insulin-dependent, IDDM) diabetic outpatients in fair blood glucose and lipid control. Two diets, each lasting two months, were compared in a randomized cross-over study. The former was a high-carbohydrate high-fiber diet for diabetic patients with Italian alimentary habits, the latter had the same composition except that 30 g of sucrose replaced 30 g of complex carbohydrates with high glycemic index (bread). The two diets contained equal amounts of carbohydrates, proteins and lipids; the only difference being the contribution of oligosaccharides to total carbohydrates (22% vs 34%) and cholesterol amount. During the control diet, glycosylated hemoglobin was substantially unchanged in both control and sucrose diet periods (control diet: 6.91 +/- 0.29 (SE) vs 6.80 +/- 0.25%; sucrose diet: 6.75 +/- 0.31 vs 6.91 +/- 0.36%). This was true also for fructosamine (control diet: 3.92 +/- 0.21 vs 3.76 +/- 0.18%; sucrose 3.50 +/- 0.14 vs 3.64 +/- 0.20 mmol/l). Circulating blood lipid levels, body weight and daily insulin dose did not show any significant variations during the study. Moderate amounts of sucrose may be allowed to IDDM patients with Italian alimentary habits without worsening diabetic control.

Podosome expression in osteoclasts: influence of high extracellular calcium concentration

In this study the effect of high extracellular calcium concentration has been evaluated, by immunofluorescence, on podosome expression in chicken osteoclasts. Cells were cultured in presence of 0.2 and 4 mM calcium for 90 minutes and microfilaments were detected, after fixation and permeabilization, by decoration with rodhamine conjugated phalloidin. Results showed that increased extracellular calcium concentration induces the inhibition of podosome expression indicating that these close-contact areas are capable of calcium-mediated regulation.

Cytoplasmic pH is regulated in isolated avian osteoclasts by a Cl-/HCO3- exchanger

Osteoclast resorb bone in an acid compartment formed by the bone-attachment site. The low pH of the resorption compartment provides a lysosome-like milieu suitable for acid proteases to degrade collagen. Solubilization of the hydroxyapatite that makes up bone mineral consumes about 2 moles of protons per moles of calcium dissolved, requiring a massive proton flux to maintain a low pH in the resorption compartment. In order to determine how the osteoclast maintains a physiological cytoplasmic pH while secreting massive amounts of acid, we studied the intracellular pH of osteoclasts using esterified fluorescein derivatives while controlling the electrolyte composition of the medium. The principal finding is that osteoclasts have a high capacity for chloride/bicarbonate exchange which enables them to maintain normal intracellular pH in the face of a large loading of base equivalents. Thus, the overall process of proton secretion during bone resorption is similar to the polarized acid elimination by renal epithelia, involving a proton pump on one surface of the cell, and a Cl-/HCO3- exchange to maintain cytoplasmic pH.

Hyperglycemic effect of sucrose ingestion in IDDM patients controlled by artificial pancreas

The hyperglycemic effect of 28 g sucrose, taken during a mixed meal, was studied in six insulin-dependent diabetes mellitus (IDDM) patients controlled by artificial pancreas. On 2 consecutive days the patients were given, in random order, two Italian meals containing macaroni, bread, meat, vegetables, fruit, olive oil, and an eggnog made with sucrose (meal A) or saccharin (meal B). The two meals were isocaloric and contained equal amounts of carbohydrates. The feedback control on blood glucose continued for 180 min after the meals. Plasma glucose levels and insulin infusion rates delivered by the artificial pancreas after the two test meals did not show any significant differences regarding basal and peak values, peak times, and areas under the curves. A modest amount of sucrose, taken during a mixed meal, does not produce a hyperglycemic effect higher than an equal amount of complex carbohydrates in IDDM patients controlled by artificial pancreas. The same may be expected in well-controlled IDDM patients in conventional therapy because a correlation exists between insulin requirement for conventional therapy and insulin delivered during glucose-controlled insulin infusion.

Possible effectiveness of plasmapheresis and immunosuppressive therapy in reversing subcutaneous insulin resistance: a case report

Severe resistance to subcutaneous insulin with normal sensitivity to intravenous insulin developed in a 39 year old woman affected by type 1 diabetes mellitus. The patient had been treated for ten months with continuous intravenous or intraperitoneal insulin before undergoing pancreatic transplantation. After surgery repeated plasmapheresis were performed and immunosuppressive therapy was undertaken. When studied again, one month after surgery, the patient showed normal sensitivity to subcutaneous insulin. Our data suggest that plasmapheresis and/or immunosuppressive treatment could have played a role in reversing insulin resistance.

Effects of mixing short- and intermediate-acting insulins on absorption course and biologic effect of short-acting preparation

The effects of mixing short- and intermediate-acting insulins (Actrapid MC and Monotard MC) were studied in seven diabetic patients. On different days, 0.16 IU/kg of Actrapid and 0.24 IU/kg of Monotard were administered to each subject in separate injections and combined in the same syringe. Free-insulin curves and the biologic effect of insulin, assessed by the glucose-clamp technique, were compared. The absorption rate of regular insulin was higher when injected separately from the intermediate-acting preparation: the incremental areas of free insulin above basal levels, up to 90 min after the administration of the hormone, were 32 +/- 5 vs. 21 +/- 3 microU X ml-1 X min-1 (P less than .02). In the same period, glucose infused to sustain glycemia showed no significant differences (2.8 +/- 0.4 vs. 2.4 +/- 0.3 mg X kg-1 X min-1 after the administration of insulin in separate and combined injection, respectively). The difference in insulin profiles is not translated into a significant difference in glucose requirement. This might be a consequence of a flattening of the insulin dose-response curve due to insulin resistance of diabetic subjects. The slight delay in insulin action of Actrapid when mixed with Monotard is probably irrelevant in clinical practice.