Exploring Cannabinoids with Enhanced Binding Affinity for Targeting the Expanded Endocannabinoid System: A Promising Therapeutic Strategy for Alzheimer's Disease Treatment

Despite decades of rigorous research and numerous clinical trials, Alzheimer's disease (AD) stands as a notable healthcare challenge of this century, with effective therapeutic solutions remaining elusive. Recently, the endocannabinoid system (ECS) has emerged as an essential therapeutic target due to its regulatory role in different physiological processes, such as neuroprotection, modulation of inflammation, and synaptic plasticity. This aligns with previous research showing that cannabinoid receptor ligands have the potential to trigger the functional structure of neuronal and brain networks, potentially impacting memory processing. Therefore, our study aims to assess the effects of prolonged, intermittent exposure (over 90 days) to JWH-133 (0.2 mg/kg) and an EU-GMP certified Cannabis sativa L. (Cannabixir® Medium Flos, 2.5 mg/kg) on recognition memory, as well as their influence on brain metabolism and modulation of the expanded endocannabinoid system in APP/PS1 mice. Chronic therapy with cannabinoid receptor ligands resulted in reduced anxiety-like behavior and partially reversed the cognitive deficits. Additionally, a reduction was observed in both the number and size of Aβ plaque deposits, along with decreased cerebral glucose metabolism, as well as a decline in the expression of mTOR and CB2 receptors. Furthermore, the study revealed enlarged astrocytes and enhanced expression of M1 mAChR in mice subjected to cannabinoid treatment. Our findings highlight the pivotal involvement of the extended endocannabinoid system in cognitive decline and pathological aspects associated with AD, presenting essential preclinical evidence to support the continued exploration and assessment of cannabinoid receptor ligands for AD treatment.

A Nanostructured Protein Filtration Device for Possible Use in the Treatment of Alzheimer's Disease-Concept and Feasibility after In Vivo Tests

BACKGROUND

Alzheimer's disease (AD), along with other neurodegenerative disorders, remains a challenge for clinicians, mainly because of the incomplete knowledge surrounding its etiology and inefficient therapeutic options. Considering the central role of amyloid beta (Aβ) in the onset and evolution of AD, Aβ-targeted therapies are among the most promising research directions. In the context of decreased Aβ elimination from the central nervous system in the AD patient, the authors propose a novel therapeutic approach based on the "Cerebrospinal Fluid Sink Therapeutic Strategy" presented in previous works. This article aims to demonstrate the laborious process of the development and testing of an effective nanoporous ceramic filter, which is the main component of an experimental device capable of filtrating Aβ from the cerebrospinal fluid in an AD mouse model.

METHODS

First, the authors present the main steps needed to create a functional filtrating nanoporous ceramic filter, which represents the central part of the experimental filtration device. This process included synthesis, functionalization, and quality control of the functionalization, which were performed via various spectroscopy methods and thermal analysis, selectivity measurements, and a biocompatibility assessment. Subsequently, the prototype was implanted in APP/PS1 mice for four weeks, then removed, and the nanoporous ceramic filter was tested for its filtration capacity and potential structural damages.

RESULTS

In applying the multi-step protocol, the authors developed a functional Aβ-selective filtration nanoporous ceramic filter that was used within the prototype. All animal models survived the implantation procedure and had no significant adverse effects during the 4-week trial period. Post-treatment analysis of the nanoporous ceramic filter showed significant protein loading, but no complete clogging of the pores.

CONCLUSIONS

We demonstrated that a nanoporous ceramic filter-based system that filtrates Aβ from the cerebrospinal fluid is a feasible and safe treatment modality in the AD mouse model. The presented prototype has a functional lifespan of around four weeks, highlighting the need to develop advanced nanoporous ceramic filters with anti-biofouling properties to ensure the long-term action of this therapy.

Modern Approaches in Wounds Management

Wound management represents a well-known continuous challenge and concern of the global healthcare systems worldwide. The challenge is on the one hand related to the accurate diagnosis, and on the other hand to establishing an effective treatment plan and choosing appropriate wound care products in order to maximize the healing outcome and minimize the financial cost. The market of wound dressings is a dynamic field which grows and evolves continuously as a result of extensive research on developing versatile formulations with innovative properties. Hydrogels are one of the most attractive wound care products which, in many aspects, are considered ideal for wound treatment and are widely exploited for extension of their advantages in healing process. Smart hydrogels (SHs) offer the opportunities of the modulation physico-chemical properties of hydrogels in response to external stimuli (light, pressure, pH variations, magnetic/electric field, etc.) in order to achieve innovative behavior of their three-dimensional matrix (gel-sol transitions, self-healing and self-adapting abilities, controlled release of drugs). The SHs response to different triggers depends on their composition, cross-linking method, and manufacturing process approach. Both native or functionalized natural and synthetic polymers may be used to develop stimuli-responsive matrices, while the mandatory characteristics of hydrogels (biocompatibility, water permeability, bioadhesion) are preserved. In this review, we briefly present the physiopathology and healing mechanisms of chronic wounds, as well as current therapeutic approaches. The rational of using traditional hydrogels and SHs in wound healing, as well as the current research directions for developing SHs with innovative features, are addressed and discussed along with their limitations and perspectives in industrial-scale manufacturing.

360-Degree Perspectives on Obesity

Alarming statistics show that the number of people affected by excessive weight has surpassed 2 billion, representing approximately 30% of the world's population. The aim of this review is to provide a comprehensive overview of one of the most serious public health problems, considering that obesity requires an integrative approach that takes into account its complex etiology, including genetic, environmental, and lifestyle factors. Only an understanding of the connections between the many contributors to obesity and the synergy between treatment interventions can ensure satisfactory outcomes in reducing obesity. Mechanisms such as oxidative stress, chronic inflammation, and dysbiosis play a crucial role in the pathogenesis of obesity and its associated complications. Compounding factors such as the deleterious effects of stress, the novel challenge posed by the obesogenic digital (food) environment, and the stigma associated with obesity should not be overlooked. Preclinical research in animal models has been instrumental in elucidating these mechanisms, and translation into clinical practice has provided promising therapeutic options, including epigenetic approaches, pharmacotherapy, and bariatric surgery. However, more studies are necessary to discover new compounds that target key metabolic pathways, innovative ways to deliver the drugs, the optimal combinations of lifestyle interventions with allopathic treatments, and, last but not least, emerging biological markers for effective monitoring. With each passing day, the obesity crisis tightens its grip, threatening not only individual lives but also burdening healthcare systems and societies at large. It is high time we took action as we confront the urgent imperative to address this escalating global health challenge head-on.

Acute Toxicity and Pharmacokinetic Profile of an EU-GMP-Certified Cannabis sativa L. in Rodents

The conundrum of Cannabis sativa's applications for therapeutical purposes is set apart by the hundreds of known and commercially available strains, the social, cultural and historical context, and the legalization of its use for medical purposes in various jurisdictions around the globe. In an era where targeted therapies are continuously being developed and have become the norm, it is imperative to conduct standardized, controlled studies on strains currently cultivated under Good Manufacturing Practices (GMP) certification, a standard that guarantees the quality requirements for modern medical and therapeutic use. Thus, the aim of our study is to evaluate the acute toxicity of a 15.6% THC: <1% CBD, EU-GMP certified, Cannabis sativa L. in rodents, following the OECD acute oral toxicity guidelines, and to provide an overview of its pharmacokinetic profile. Groups of healthy female Sprague-Dawley rats were treated orally with a stepwise incremental dose, each step using three animals. The absence or presence of plant-induced mortality in rats dosed at one step determined the next step. For the EU GMP-certified Cannabis sativa L. investigated, we determined an oral LD50 value of over 5000 mg/kg in rats and a human equivalent oral dose of ≈806.45 mg/kg. Additionally, no significant clinical signs of toxicity or gross pathological findings were observed. According to our data, the toxicology, safety and pharmacokinetic profile of the tested EU-GMP-certified Cannabis sativa L. support further investigations through efficacy and chronic toxicity studies in preparation for potential future clinical applications and especially for the treatment of chronic pain.

A novel device and system concept for therapeutic plasma exchange in rats

INTRODUCTION

Therapeutic plasma exchange (TPE) has been developed more than 100 years ago in an animal model and adapted to humans 30 years later. Since then, the TPE research on animal models is lacking, mainly due to difficulties raised by the scaling of the plasmapheresis unit so that the animal's cardiovascular parameters are not considerably affected.

METHODS

The system concept of a novel TPE device with continuous hemodynamic monitoring in small rodent models has been used.

RESULTS

A continuum TPE unit for rats has been developed, able to produce up to 95% plasma exchange rate without any TPE-related hemodynamic impairment, monitored up to 35 days after the procedure.

CONCLUSION

The TPE unit for rats was able to produce 95% plasma exchange rate in non-anesthetized animals, enabling a full translation of the human TPE into an animal model. The newly developed plasmapheresis unit enable a wide range of more accurate preclinical evaluation, with cardiac parameters monitoring, using small rodents in awaken state.

A195 GEOEPIDEMIOLOGICAL CHANGES DUE TO ALTERATIONS IN DIAGNOSTIC ROME CRITERIA FOR IRRITABLE BOWEL SYNDROME

Background

Irritable bowel syndrome (IBS) is a positive diagnosis based on consensus opinions. The Rome (R) criteria, have gone through 4 rounds. R4 restricted diagnosis of IBS over R3, reducing global prevalence. Previously, there were no correlations of world distributions of IBS and Inflammatory Bowel Disease [IBD](Lovell). There are also epidemiological studies showing relationships between IBD and national wealth.

Aims

We reevaluate relationships among different R criteria and latitude(Lat), lactose digestion status (LNP), human development index(HDI), gross domestic product/capita(GDP/c), Crohn’s disease (CD and ulcerative colitis (UC) incidence(i) and prevalence(p).

Methods

Literature on world prevalence of national IBS (Oka,Sperber), IBD rates (Ng), and GDP (Lopez Ruiz) (4) were sought on PubMed and Google Scholar.National HDI(08 or 2016) were available on the internet (http://hdr.undp.org/en/data). National lactase distributions and latitudes were quoted (Szilagyi). Target dates were for the year 2008±8yrs. After log transformation of IBD incidence, Pearson’s correlations were carried out.(strong at; r ≥0.7, moderate ≥0.5, weak ≤ 0.49, negligible ≤ 0.3). (significance was p&lt;0.05).

Results

Correlations of HDI08 and HDI16 was 0.98. Comparisons of R2 and a composite based on Manning, R 1 and 2 (Lovell) was r = 0.96 (N21 countries), Correlation of R 3 and 4 were r = 0.85 (N17). Correlations of R2 and R3 or R4 were negligible (r = -0.2 (n15) and -0.12 (N22). Correlations of R2 and both economic metrics were weak but significant (r = 0.42 – r = 0.49, p &lt; 0.03 - &lt; 0.001). However, correlations of metrics with R3 were non significant and negligible with R4. Comparisons of R2 with LNP or Lat were negligible, but those of R3 or R4 with Lat were significant. Comparisons of R3 with CDp showed a strong correlation while R4 showed a weak but significant correlation with UCi. R2 had negligible correlations with IBD.

Conclusions

Although, these results are based on limited data variations in R criteria have changed relations with IBS prevalence.Earlier R criteria showed increased IBS in poorer nations. The recent R3 and R4 criteria are independent of national economy, but show more relations with increasing latitudes. Consequences of the change include R3 and 4 reflecting western society symptoms perhaps linking it more with IBD.It is unclear if this new relationship incorporates an irritable inflammatory bowel syndrome (Gajula).The generalizability therefore of the new R4 criteria may still be limited.

Table: Rome criteria compared to variables.

Statistical significance * &lt; 0.03, ** ≤ 0.05

Funding Agencies

None

A157 REAL-WORLD TIGHT OBJECTIVE MONITORING WITH ADALIMUMAB LEADS TO EARLIER DOSE OPTIMIZATION AND HIGHER CLINICAL REMISSION RATES AT 12 MONTHS

Background

Data suggests that tight objective monitoring of inflammatory bowel diseases (IBD) may improve one-year clinical outcomes.

Aims

The goal of this study is to assess the adherence to serial tight objective monitoring, via clinical symptoms and biomarkers, and the effect of such tight monitoring on one year outcome in IBD patients at an academic and an university-affiliated center.

Methods

We retrospectively reviewed the chart of 428 consecutive IBD patients who started adalimumaby at the McGill University Health Center and Jewish General Hospital (Montreal, Canada) between January 1, 2015 and January 1, 2019 [338 Crohn’s disease(CD), 90 ulcerative colitis(UC)]. Clinical symptoms (assessed by Harvey-Bradshaw-Index and partial Mayo), C-Reactive Protein(CRP), and fecal calprotectin(FCAL) were captured at treatment initiation and at 3, 6, 9, and 12 months. Combined adherence was defined as the evaluation of ≥2 of 3 parameters(clinical, CRP, FCAL). Dose optimization and drug sustainability curves were plotted by Kaplan-Meier method.

Results

Clinical symptoms were assessed in nearly all patients at 3 (CD-UC:95-94%), 6 (90-83%), 9 (86-85%) and 12 (96-89%) months. CRP was also available for most patients but the frequency of assessment decreased in CD patients over the study period. In comparison, compliance to serial FCAL testing was low throughout the follow-up period. Clinical remission at one-year was significantly higher in patients who were adherent to early assessment visit at 3 months (p=0.001 both for CD and UC). Adherence to early follow-up also resulted in earlier dose optimisation in both CD and UC patients(pLogrank=0.026 for UC and p=0.09 for CD). However, the overall drug sustainability did not differ.

Conclusions

Clinical assessment and CRP, but not FCAL, were frequently assessed in patients starting adalimumab. Adherence to early objective combined follow-up visits resulted in earlier dose optimization and improved one-year clinical outcomes but did not change drug sustainability rates.

Funding Agencies

None

A114 AMEBIC COLITIS AS A RARE CAUSE OF PSEUDOMEMBRANOUS COLITIS

Background

Globally, Entamoeba histolytica results in nearly 40 million cases of amebic colitis and 50 000 deaths annually. The disease is common in Africa, Asia, and Central and South America but infection remains rare in North America, limited to travelers, immigrants, and immunocompromised hosts. The disease ranges from asymptomatic chronic colonization to dysentery and fulminant colitis. Endoscopically, the ulcerations may demonstrate the non-specific pattern of pseudomembranous colitis that is classically seen with Clostridoides difficile infection.

Aims

To discuss an unusual case of pseudomembranous colitis caused by Entamoeba histolytica.

Methods

The patient records were reviewed and a review of the literature was performed.

Results

A 54-year-old male with a remote history of peptic ulcer disease visiting from Guinea presented with a 3-day history of right sided abdominal cramping and intermittent bloody diarrhea. The pain was gradual in onset with moderate severity. He reported &gt;5 episodes of blood intermixed with brown stools. He was incidentally diagnosed with hypertension and started on treatment two weeks prior. He denied recent antibiotic use and family history was unremarkable for inflammatory bowel disease (IBD) or other forms of colitis. There was no abdominal tenderness or bleeding on rectal examination. He had a stable normocytic anemia (Hgb 114), leukocytosis (13.4) with neutrophilia, and elevated C-reactive protein (43.4 mg/L). He was discharged with presumed resolving ischemic colitis. Colonoscopy showed diffuse colonic involvement with areas of patchy yellow plaques and a mix of shallow and deep non-bleeding ulcers suggestive of pseudomembranous colitis. He was discharged with empiric oral vancomycin, later discontinued following negative C. difficile toxin testing. Stool cultures and microscopy detected Entamoeba histolytica. Limited biopsies of the nodular ulcers failed to show any pathologic alterations or trophozoites. The patient was treated for luminal amebiasis with oral metronidazole and paromomycin but was lost to follow up on return to his native country.

Conclusions

Amebic colitis remains a rare entity in the developed world and is limited to travelers or recent immigrants from endemic areas. Diagnosis is typically difficult and may require endoscopy as its clinical course may resemble IBD or infectious colitis. Limited cases exist of fulminant amebic colitis causing pseudomembranous colitis, with even fewer cases of mild dysentery having this appearance. Despite pseudomembranous colitis being commonly associated with C. difficile infection, this pattern of mucosal injury may be seen with other enteric bacterial and protozoan infections, inflammatory conditions, or use of certain medications. In the appropriate clinical context, on exclusion of C. difficile, secondary causes such as active amebiasis should be considered.

Funding Agencies

None

Meta-analysis: the diagnostic accuracy of lactose breath hydrogen or lactose tolerance tests for predicting the North European lactase polymorphism C/T-13910

BACKGROUND

  The diagnostic accuracy of two indirect tests of lactose digestion, lactose breath hydrogen and lactose tolerance tests, have not been systematically reviewed for comparison with available publications on genotype.

AIM

  To perform a meta-analysis of available studies that compares the north-European genetic polymorphism C/T-13910 with the lactose breath hydrogen and the lactose tolerance tests, to determine their ability to predict geno/phenotype relationships. We examine the effects of lactose loading dose, inclusion of children and latitudes of study centre on comparative outcome.

METHODS

  An electronic database of the literature as well as individual references in articles were searched with the theme of genetics of lactase and comparisons with breath or lactose tolerance tests were carried out. Random effect and fixed effect models were used for breath and lactose tolerance tests respectively, to report summary accuracy measures with 95% confidence intervals (CI).

RESULTS

  The search revealed 19 studies: 17 evaluated breath hydrogen, five lactose tolerance test (3/17 overlapped). Overall sensitivity was 0.88 (CI, 0.85-0.90), specificity was 0.85 (CI, 0.82-0.87) for breath test. Heterogeneity was explored by adjusting for studies including children, high or low dose lactose and to some extent by site of study. The lactose tolerance test showed sensitivity of 0.94 (0.9-0.97) and specificity of 0.90 (0.84-0.95) with a nonsignificant heterogeneity.

CONCLUSION

  The diagnostic accuracy of both tests individually reflects expected geno/phenotypes when the populations are well defined.

There is no difference in the disease severity of gastro-oesophageal reflux disease between patients infected and not infected with Helicobacter pylori

BACKGROUND

The role of Helicobacter pylori in gastro-oesophageal reflux disease (GERD) is controversial.

AIM

To compare the severity of GERD in infected vs. non-infected patients, as part of an ongoing randomized controlled trial that examines the impact of H. pylori eradication on GERD-related outcomes.

METHODS

Consecutive GERD patients underwent urea breath testing and completed validated GERD symptom severity, and quality of life questionnaires as well as, 24-h pH-metry. These parameters, as well as demographics and endoscopic findings were assessed in double-blinded fashion and compared between H. pylori-infected and non-infected subjects.

RESULTS

Helicobacter pylori-infected GERD patients (n=50) were significantly older and less educated than non-infected patients (n=51). They also used proton pump inhibitors less often but had no difference in symptoms (as measured with both the Spechler's Activity Index and the Gastrointestinal Symptom Rating Scale), quality of life, endoscopic findings or 24-h pH-metry findings.

CONCLUSION

This prospective, double-blind study demonstrates, using excellent GERD quantifying measures including validated symptom severity scores, endoscopy, and 24-h pH-metry, that there exist no clinically significant differences in clinical or laboratory-related GERD manifestations between H. pylori-infected and non-infected GERD patients.

Review article: lactose--a potential prebiotic

Lactose maldigestion, which affects a large majority of the world's population, has been mostly linked with uncomfortable symptoms. In addition, dairy consumption is variably blamed or recommended for a number of ill effects. There is, however, emerging evidence that certain lactic acid-producing bacteria, which selectively consume prebiotics, may be beneficial against some lower intestinal diseases. Lactose maldigestion and lactose should perhaps be re-evaluated as a potential provider of such a prebiotic. This historical and observational review discusses lactose and argues the opinion that it has prebiotic potential. Moreover, in maldigesters, natural ingestion or lack thereof may be relevant in the pathogenesis of diseases such as colorectal cancer and inflammatory bowel diseases.

Systematic review: the use of somatostatin or octreotide in refractory diarrhoea

BACKGROUND

Somatostatin and octreotide have multiple effects which make them ideal for treating diarrhoea of different aetiologies. Their use in a variety of conditions with refractory diarrhoea, however, is based on a limited number of studies.

AIM

We undertook a systematic review of the available English literature to maximize an evidence-based approach to the treatment of refractory diarrhoea. We tested the hypothesis that efficacy is independent of aetiology.

METHODS AND RESULTS

A Medline and individual article search from 1965 to 2000 was undertaken on the use of somatostatin and octreotide in diarrhoea. All reports containing at least five subjects were included. The percentage response in case series and randomized controlled trials was compared, and a meta-analysis of randomized controlled trials where patient level data were provided was carried out. There were 30 publications found (18 case series, 12 randomized controlled trials). The response percentage was 73% overall in case series and 64% in randomized controlled trials (not significant). A meta-analysis of nine randomized controlled trials revealed significant heterogeneity despite an overall relative risk of 0.5 (95% confidence interval, 0.27-0.91). Subgroup analysis of the largest aetiological groups showed that acquired immunodeficiency syndrome studies were homogeneous, but somatostatin and octreotide were less effective. Post-chemotherapy studies remained heterogeneous and somatostatin and octreotide were highly effective.

CONCLUSIONS

While this review strengthens the consensus guidelines on the use of somatostatin and octreotide for refractory diarrhoea, evidence-based support requires additional studies.

Improved parameters of lactose maldigestion using lactulose

Lactulose is a disaccharide derived from lactose. There has been recent rekindling of interest in the possible benefits of pro- and prebiotics: mainly, lactic acid-producing bacteria and lactulose for the lower intestine. Since lactose maldigestion is a common genetic trait, we undertook this study to delineate similar effects between these two disaccharides. Nine healthy lactose maldigesting subjects underwent two separate periods of three weeks adaptation, first with 10 g twice daily lactulose and then 1.5 g twice daily lactose (in milk). Adaptation was defined by reduced breath Hydrogen (BH2) and symptoms after 50 g lactose challenges. In six subjects fecal beta-galactosidase was measured. All subjects consumed some lactose daily. In the first period, eight subjects improved symptoms and reduced BH2 significantly, while in the second period they did not. Fecal beta-galactosidase significantly increased after lactulose. This study supports the notion that lactulose and lactose may have similar clinical effects.

Improvement of perinatal outcome in diabetic pregnant women

Obstetrical and perinatal outcomes in newborns of diabetic pregnant women depend on metabolic control and fetal surveillance during pregnancy. The effects of fetal surveillance on perinatal mortality and morbidity was analyzed in diabetic pregnant women with appropriate glucose control in our regional center for diabetes and pregnancy. 480 deliveries complicated by frank or gestational diabetes occurred in our Department in the period of 1988-1999. Perinatal mortality and morbidity, prevalence of premature deliveries, methods of fetal surveillance, options for respiratory distress syndrome (RDS) profilaxis, cesarean section rate, timing of delivery and its indications and occurrence of malformations have been analyzed. It was found that malformation rate and perinatal mortality may be reduced to even lower level than that of in healthy pregnant women by appropriate glucose control and by using the latest methods of intrauterine fetal surveillance including cardiotocography (non stress test and oxytocin challenge test), doppler fetal artery velocimetry and fetal pulse oximetry. Timing of delivery was needed in 35% of the cases with IDDM and 15% of gestational diabetes due to chronic placental insufficiency. If labour induction was needed before the 38 weeks, amniocentesis was performed to test fetal lung maturity. Direct fetal glucocorticoid administration was used to enhance fetal lung maturation in 14 cases. C-section rate was slightly higher than that of in non diabetic pregnant women. Our perinatal morbidity data (macrosomia, hyperbilirubinemia, hypoglycemia, injuries, infections) are comparable with the data from the literature. Although perinatal mortality with the help of thorough fetal surveillance is even better in diabetic pregnant women than in non diabetic patients, future eye should be focused on factors affecting perinatal morbidity, because it is still higher than in newborns of healthy mothers.

Possible therapeutic use of loperamide for symptoms of lactose intolerance

OBJECTIVES

To examine a potential practical therapeutic use of loperamide (Lo) to decrease the symptoms of lactose intolerance.

SUBJECTS AND METHODS

Nineteen (eight men, 11 women) healthy lactose maldigesters (18 of 19 with symptoms) underwent a 25 g lactose challenge on five separate days. Breath hydrogen was measured, areas under the curve (AUC) were calculated for 4 h, and 4 and 12 h symptom scores were recorded. After establishing baseline measurements, test doses of 4 mg, 8 mg and 12 mg Lo were randomly administered without placebo in a double-blind manner. As well, each subject received seven lactase tablets, in a random, unblinded manner.

RESULTS

The median AUC and mean oral cecal transit time followed dose response expectations; however, only lactase treatment achieved significance. Nevertheless, 8 mg Lo significantly improved symptom scores, which were statistically indistinguishable from those of lactase. Four subjects complained of delayed constipation and cramps with various doses of Lo.

CONCLUSIONS

Lo monotherapy for lactose intolerance is not economical and may have some side effects. However, Lo may be studied further as an adjunctive treatment of lactose intolerance in an effort to reduce the need for complete lactose digestion. Such a manoeuvre may allow rapid colonic adaptation, which in turn may be beneficial for prophylaxis for a number of colonic diseases.

Use of interferon for prevention of hepatocellular carcinoma in cirrhotic patients with hepatitis B or hepatitis C virus infection

The incidence of hepatocellular carcinoma in North America is increasing. Current debate focuses on whether interferon administered to cirrhotic patients-with or without biochemical or virologic response-delays or prevents cancer of the liver. Review of the literature revealed several studies that showed improvement in or delay in progression of histologic fibrosis in patients with hepatitis C virus (HCV) infection. In patients with hepatitis B virus (HBV) infection, conversion to the nonreplicative stage may be associated with histologic improvement. However, only 11 studies (6 of HCV, 3 of HBV, and 2 of HCV and HBV) compared development of hepatocellular carcinoma in interferon-treated patients with cirrhosis and cirrhotic patients who were not treated with interferon. Although no firm statistical conclusions could be drawn, the literature suggests that interferon therapy may prevent hepatocellular carcinoma in patients with cirrhosis, particularly those infected with HCV. Interferon treatment cannot be recommended for all persons with cirrhosis and HBV or HCV infection because the current evidence is only suggestive. Long-term randomized, controlled trials may provide definitive data; however, it will be difficult, if not impossible, to conduct such trials because of the improved efficacy of combination therapy with interferon and ribavirin in patients with chronic HCV infection and the development of new therapies for patients with HBV infection.

Altered colonic environment, a possible predisposition to colorectal cancer and colonic inflammatory bowel disease: rationale of dietary manipulation with emphasis on disaccharides

A recurrent theme in the schema of pathogenetic mechanisms attributed to colorectal cancer (CRC) and inflammatory bowel disease (IBD) is the interaction between genes and environment. Dietary and other environmental factors, and lower intestinal flora and their chemical interactions occur in the pathogenesis of both. Events at the mucosal surface may be influenced by factors in the luminal environment and by contributions of the host. In addition, both forms of IBD--Crohn's disease (CD) and ulcerative colitis (UC)--have distinctive associated host events. Even within CD and UC, different clinical patterns and prognoses may have different specific host mechanisms. Some of the current putative pathogenetic processes in CRC and IBD are reviewed. Particular attention is given to hypotheses relating to the role of dietetic substances, mainly fibre and dairy products, and how they may affect disease formation. It is argued that within the context of hypotheses proposed for possible beneficial effects of these two dietetic factors, CRC and IBD may be considered together. Further support is lent to arguments that similar and additional hypothetical features ascribed to beneficial effects of fibre may be attributed to disaccharides, lactose and its derivatives, lactulose and lactitol.

Sequence and homology model of 3-isopropylmalate dehydrogenase from the psychrotrophic bacterium Vibrio sp. I5 suggest reasons for thermal instability

The leuB gene from the psychrotrophic strain Vibrio sp. I5 has been cloned and sequenced. The gene codes for 3-isopropylmalate dehydrogenase, a 360-residue, dimeric enzyme involved in the biosynthesis of leucine. Three recently solved homologous isopropylmalate dehydrogenase (IPMDH) crystal structures from thermophilic and mesophilic organisms have been used to build a homology model for the psychrotrophic IPMDH and to deduce the possible structural reasons for its decreased thermostability. According to our model the psychrotrophic IPMDH contains fewer stabilizing interactions than its mesophilic and thermophilic counterparts. Elements that have been identified as destabilizing in the comparison of the psychrotrophic, mesophilic and thermophilic IPMDHs are a smaller number of salt-bridges, a reduction in aromatic-aromatic interactions, fewer proline residues and longer surface loops. In addition, there are a number of substitutions of otherwise strictly conserved residues that can be linked to thermostability.

Nausea, vomiting and diarrhea: an unusual presentation of multiple sclerosis

The case of a young woman who presented with nausea, vomiting and diarrhea is outlined; the etiology turned out to be a first attack of multiple sclerosis. Plausible mechanisms are discussed.

Adverse reactions to food constituents: allergy, intolerance, and autoimmunity

Food allergies and intolerance represent important health concerns to consumers who are predisposed to these illnesses. Unlike many current food safety issues, food sensitivities are complicated by both complex and multiple individual adverse reactions, which can vary from emotional to pathophysiological ailments. In some instances, the underlying mechanisms that result in the development of food allergies or intolerance have marked differences but produce common symptoms. The present-day diagnosis of these disorders can be impeded by intrinsic limitations in generating accurate information from patient history and biochemical, physicochemical, and immunochemical tests. Oral challenge tests represent effective methods for confirming and testing food allergens and food intolerance; however, these procedures are often restricted to clinical trials. It is important to be able to distinguish among food allergy, intolerance, and autoimmune disease in the management of these disorders. The role of food in the development of autoimmune disease may be exemplified by celiac disease, a food-induced enteropathy, requiring exposure to prolamins in wheat, rye, and barley. Various wheat and soy protein sources, including the soy protein isolates used to make infant formulas, have been related to juvenile or insulin-dependent diabetes mellitus (IDDM), a common chronic disease of childhood. Employing food process technologies to eliminate food constituents with potential for intolerance in some individuals is a potentially viable approach for reducing risk to food-related disorders. Finally, the development of food labelling regulations that require the identification of potential food allergens or agents for intolerance in the ingredient declaration on prepackaged food is a positive step toward the prevention of severe adverse reactions in hypersensitive individuals.

Lactose handling by women with lactose malabsorption is improved during pregnancy

OBJECTIVE

To evaluate lactose handling among women in late pregnancy and post partum to determine whether lactose handling is altered in pregnancy.

DESIGN

Prospective study of lactose intolerance among pregnant women with and without lactose malabsorption.

SETTING

Gastroenterology service of the Sir Mortimer B. Davis-Jewish General Hospital, Montreal.

PATIENTS

Thirty-three pregnant women, of whom 18 had lactose malabsorption, 12 did not and 3 were excluded.

OUTCOME MEASURES

Lactose breath hydrogen (BH2) concentration after ingestion of lactose or lactulose; comparison before and after delivery of area under the curve (AUC) for lactose, oral-cecal transit time (OCTT) for lactulose, lactose-BH2-derived transit time and estimated dietary lactose consumption.

RESULTS

After weaning (at a median time of 9 months after delivery), 28 of the women returned for follow-up. Of the 12 who could absorb lactose before delivery, 4 could no longer absorb lactose. Of the other 16 women, lactose intolerance worsened in 12, remained the same in 2 and improved in 2. The AUC was greater (p < 0.005), the maximal BH2 concentration was higher (p = 0.004) and the number of women whose BH2 concentration peaked was fewer (p < 0.025) post partum than before delivery. The women's symptoms during and after lactose BH2 tests were also greater post partum. The OCTT (based on the lactulose BH2 test) was shorter post partum (p = 0.001). Transit time derived from lactose BH2 tests was also shorter, but not significantly so. The OCTT was not inversely correlated with the change in AUC before and after delivery, but the lactose-BH2-derived transit time was inversely correlated. Pregnant women consumed more lactose before delivery than afterward (p < 0.004).

CONCLUSIONS

Women with lactose malabsorption handle lactose better than usual in late pregnancy. Slow intestinal transit and bacterial adaptation to increased lactose intake may be primarily responsible.

Influence of loperamide on lactose handling and oral-caecal transit time

BACKGROUND

The influence of pharmacologically prolonged oral caecal transit time on lactose handling is examined in the wake of finding improved lactose handling during naturally occurring prolonged oral-caecal transit time.

METHODS

Sixteen normal male volunteers with lactose maldigestion were pretreated with 8 and 12 mg loperamide on different days and lactose handling was compared by measuring areas under the curve during lactose breath H2 testing (3 h). The oral-caecal transit time was similarly measured using lactulose and exhaled breath H2. Symptom scores were recorded and, in three subjects, blood sugar was simultaneously measured.

RESULTS

The mean +/-S.E.M. baseline oral-caecal transit time was 56.9 +/- 5.9 min. Loperamide significantly prolonged oral-caecal transit time (90.3 +/- 11.1 and 82.1 +/- 13.9 min for 12 and 8 mg loperamide, respectively; P < 0.05). The lactose breath H2 area under the curve with 12 mg loperamide was significantly less than at baseline (7685 +/- 985.6 vs. 10243.1 +/- 1607, respectively; P < 0.05). Significantly fewer symptoms were recorded with both doses of loperamide during the 3 h test but with 12 mg loperamide only on follow-up. There was no significant rise in blood sugar at any time in the three subjects studied.

CONCLUSIONS

Loperamide-induced graded prolongation of oral-caecal transit time is associated with significantly improved lactose handling as measured by a reduction of the area under the curve. Symptoms of lactose intolerance may also be improved with loperamide. Prolongation of oral-caecal transit time with loperamide may be useful as adjunctive or primary therapy of carbohydrate intolerance in patients with rapid transit.

Caco-2 cell disaccharidase activities are unaffected by gestational hormones

We previously reported that lactose handling was significantly improved during late-phase pregnancy in women with a genetically determined adult-type hypolactasia. However, the adaptive mechanisms underlying the enhanced lactose digestion during pregnancy are not clear. Progesterone therapy has been associated in animals with increased intestinal lactase activity. To investigate the potential role of progesterone and estrogen as modulators of human lactase activity during pregnancy, we employed the human-derived intestinal epithelial Caco-2 cell line. Measurements of lactase and sucrase activities were performed in parallel with DNA content in progesterone- and estrogen-treated cells after 5, 10, and 30 days of confluency. Caco-2 monolayer DNA content was observed to increase with duration of culture to an equivalent extent in both hormone-treated and control cultures. Lactase and sucrase activities were similarly unaltered by incubation with either progesterone or estrogen, at any time point tested. These data demonstrate that gestational hormones do not influence intestinal cell number nor disaccharidase activity in Caco-2 cells, at the doses tested. Although these studies were carried out in a malignant cell line, our data suggest that the improved lactose handling observed during pregnancy is probably related to prolonged intestinal transit.

Determinants of prolonged oral cecal transit time during late phase pregnancy

We examined the course of delayed oral cecal transit time (OCTT) and the impact of different variables in late pregnancy. Thirty-three women in late trimester were evaluated and 29 were re-tested post partum. Results were compared with 17 controls. A breath hydrogen test was used to measure OCTT. The impact of 3 demographic and 5 biochemical parameters was evaluated. Oral cecal transit time (99.2 +/- 7.8 min) during pregnancy was significantly prolonged compared both with controls (63.5 +/- 8.7 min) (p = 0.0042) and post partum (68.5 +/- 6.4 min) (p < 0.002). However, 40% during pregnancy had a normal OCTT. Post partum, 8 (29.6%) continued to have delayed OCTT. Serum free T4 levels were significantly lower than in controls (p < 0.0001) and post partum (p < 0.001), but did not correlate with OCTT. Gravidity rank correlated with OCTT (p = 0.022). By multivariate analysis, only 17% of the observed variability during pregnancy could be explained by these parameters. In controls, a formula including progesterone and gastrin levels was significant in explaining 54.7% of variability. Application of both formulae to post-partum returnees overpredicted OCTT; however, the one from pregnancy was more accurate. We conclude that in pregnancy multiple factors account for delayed OCTT and these may be different from controls and post partum. Pregnancy may still influence OCTT post partum.

Clinical and histopathological variation in hepatocellular carcinoma

OBJECTIVES

To assess clinical and histopathological variation in hepatocellular carcinoma from different endemic zones and to relate such variation to current putative pathogenic mechanisms of carcinogenesis.

METHODS

Review of pertinent English language articles with emphasis on regional differences as they relate to our objectives.

RESULTS

Clinical presentation of hepatocellular carcinoma is variable in different endemic zones. Such different features may depend on the interaction of different etiological initiators and, probably, promoters that can lead to different genetic aberrations. Similarly, there also may be histopathological variation. However, it is difficult to clearly delineate such differences, in part, because of lack of uniformity in reporting interpretation of histological data in the literature. And, the ethnic origin of patients is not always noted in middle and low endemic zones of hepatocellular carcinoma.

CONCLUSIONS

Distinction in clinical and histopathological variation in hepatocellular carcinoma may benefit from delineating the ethnic origin of subjects included in studies and from adoption of clear uniform terminology for benign, indeterminate, and malignant lesions.

Cullen's sign: it doesn't always mean hemorrhagic pancreatitis

Periumbilical ecchymosis, Cullen's sign, is most often considered a sign of hemorrhagic pancreatitis. We present a case of splenic rupture secondary to infectious mononucleosis in a middle-aged patient whose presenting complaint was the presence of Cullen's sign, secondary to the hemoperitoneum. The splenic rupture was managed conservatively, and the Cullen's sign resolved within 14 days of presentation.

Episodic thyrotropin (TSH) and prolactin (PRL) secretion during aging in postmenopausal women

While aging is known to decrease episodic thyrotropin (TSH) secretion in men, no detailed information is available as to age-related alterations in the TSH and prolactin (PRL) release patterns in postmenopausal women (PMW). Accordingly, we compared the TSH and prolactin (PRL) secretory profiles of 6 euthyroid younger PMW (mean age: 53.0 years) with those of 7 euthyroid older PMW (mean age: 80.4 years). In all PMW, blood samples were obtained at 10 minute intervals for 10 hours for serial determinations of TSH and PRL by RIA. While thyroxine (T4) serum concentrations were not different in younger from older PMW, triiodothyronine (T3) levels markedly (p less than 0.05) decreased in older PMW. In both younger and older PMW, TSH and PRL were secreted episodically (by Cluster pulse algorithm), with considerable inter-individual variabilities in either study group. TSH and PRL pulse attributes (interpulse intervals, frequencies, amplitudes) were comparable in younger and older PMW, although a tendency of mean TSH to increase (p = 0.18) was noted for older PMW. Mean TSH and PRL serum concentrations were positively (r = 0.94, p less than 0.01) correlated in older, whereas not in younger PMW. These observations demonstrate that the pulse characteristics of episodic TSH and PRL secretion are preserved in PMW even of old age. However, in view of markedly decreased circulating T3 concentrations and of no substantial change in the TSH pulsatile secretion in older PMW, the negative feedback on the hypothalamic-pituitary unit may be impaired in elderly women.

Reversible lactose malabsorption and intolerance in Graves' disease

Ten patients with untreated Graves' disease underwent tests to determine lactose absorption, liquid gastric emptying, and oral cecal transit time. To determine the influence of thyroid hormone status on lactose absorption, eight of these same patients had repeat studies when rendered euthyroid. Two of these eight patients also underwent studies while transiently hypothyroid. Motility studies were also evaluated in a group of 11 control subjects. Lactose malabsorption occurred in nine patients with Graves' disease. In seven patients who repeated these studies, lactose malabsorption normalized in three, symptoms induced by lactose improved in two and were unchanged in two. However, these latter two patients appeared to have improved symptoms in the transient hypothyroid state. Liquid gastric emptying was significantly faster in untreated patients than controls and treated self-same patients. Transit time was significantly faster in untreated patients than when they were rendered euthyroid. There may be a relationship between altered lactose absorption states and changes in intestinal motility in patients with Graves' disease.

Hepatocellular carcinoma: comparison of clinical features among ethnic groups in an area of low prevalence

We retrospectively surveyed the clinical features of 73 cases of hepatocellular carcinoma at two hospitals over a 12-yr period. The population was heterogeneous, with 39% representing immigrants from regions of high hepatitis B and hepatocellular carcinoma prevalence. The yearly incidence of cases was constant over the 12 yr. Patient data were analyzed by grouping into three broad categories based on origin from known high, medium, or low prevalence hepatocellular carcinoma zones. In this fashion, differences in clinical presentation were observed. Asians (N = 12) were younger, invariably presented with pain; 82% had markers of hepatitis B and did not have features of chronic liver disease. In contrast, Westerners (N = 45) were older by more than a decade. One-quarter were HBV positive and almost two-thirds were alcoholic. The clinical presentation of this group was more varied, over one-third presenting with features of decompensated liver disease or variceal bleeds. Mediterranean patients (N = 16) had features intermediary between the two other groups. A logistic regression model clinically separated patients with hepatitis B-related hepatocellular carcinoma from those with alcohol-related hepatocellular carcinoma, suggesting different ongoing pathogenetic influences.

Circulating levels of placental protein 12 (PP 12) in diabetic pregnancy complicated by retinopathy

Placental protein 12 (PP 12) is a soluble tissue antigen. Immunohistochemical studies have localized PP 12 in the placental syncytiotrophoblast, chorion and amnion, and also in the decidua. During normal pregnancy serum-PP 12 is already raised in the first trimester, there is then a peak at 18 weeks, a gradual fall until 32 weeks, and a moderate increase thereafter. The mean of the healthy control group at 18 weeks of pregnancy was 122.9 +/- 47.5 micrograms/l. The mean of the diabetic group with retinopathy at the same time was 192.2 +/- 78.8 micrograms/l. There was no significant difference between background retinopathy and the proliferative form of diabetic retinopathy. At all times during pregnancy the median values of PP 12 in diabetic pregnancies were significantly (p less than 0.01) above the control values. Increased PP 12 levels in diabetic pregnancy complicated by retinopathy are probably caused by decidual, placental and amniotic leakages.

Gastroparesis secondary to a medulloblastoma of the posterior fossa

A patient with a 4-month history of unexplained nausea and vomiting is reported. The only abnormality found initially was severe gastroparesis found by gastric emptying scan. Subsequently, a posterior fossa tumor was found. The pathogenesis of this unusual presentation and the role of the gastric emptying scan is discussed.

The effect of Danazol on the circulating levels of 34K insulin-like growth factor-binding protein (PP12) and endometrial secretory protein PP14

Twenty-four women, 11 with endometriosis and 13 with fibrocystic mastopathy, were treated with a medium dose (300-400 mg daily) of Danazol for 6 months. The circulating level of progesterone, the 34K insulin-like growth factor-binding protein (IGF-bp) and endometrial protein PP14 (placental protein 14) were measured by specific radioimmunoassays before and during treatment. The serum progesterone concentration decreased significantly during Danazol treatment, as did the serum levels of 34K IGF-bp and PP14. By the third month of therapy amenorrhoea was observed in 22 out of 24 women and this was accompanied by a further decline in the IGF-bp and PP14 levels. In light of the previous observations on the IGF-bp and PP14 synthesis by secretory endometrium and the fact that Danazol causes endometrial atrophy, these results suggest that Danazol treatment has an effect on endometrial protein secretion.

Thyroid hormones and alcoholic liver disease

Alcoholic liver disease shares with other nonthyroidal illnesses patterns of serum thyroid hormones that usually do not reflect true thyroid function. Although ethanol can affect the thyroid gland and also may directly interfere with thyroid hormone metabolism, most patients with alcoholic liver disease are euthyroid. However, some have mild hypothalamic pituitary axis dysfunction. In persons who chronically and continuously drink alcohol, there are demonstrable biochemical abnormalities similar to the effects of thyroid hormone on the liver. However, a primary pathogenetic role in alcoholic hepatitis has not been proven for this thyroid hormone mimicry. There is good clinical evidence, however, that serum thyroid hormones can serve as prognostic indicators of the course of liver disease.

Liver disease in the alcoholic

The problem of liver damage in alcoholic patients is widespread. This review discusses hepatic damage on the basis of a histologic classification of increasing severity. In the early stages, or with compensated cirrhosis, clinical and laboratory findings may not accurately reflect hepatic involvement. Furthermore, there exists a group of alcoholic patients in whom liver disease may be caused by factors other than alcohol. Nevertheless, in most patients with liver disease, certain biochemical features help to establish an alcoholic etiology. These features and the use of liver biopsy are discussed, and a practical guideline for diagnosis and follow-up is offered.

Salmonella infections complicating inflammatory bowel disease

One hundred and five of 267 patients with inflammatory bowel disease at a community hospital had recorded diarrhea, but only one had Salmonella (0.9%). Two additional patients, one from another institution, are also reported. A literature review disclosed only 37 cases, 18 of which were adequately defined clinically. Patients with IBD may not be at an increased risk for Salmonella infection. Salmonella infection may increase the severity of IBD, and therefore antibiotics may be necessary.