A Clustering Study of Dietary Patterns and Physical Activity among Workers of the Uruguayan State Electrical Company

Recent studies have shown that certain nutrients, specific food groups, or general dietary patterns (DPs) can promote health and prevent noncommunicable chronic diseases (NCCDs). Both developed and developing countries experience a high prevalence of NCCDs due to poor lifestyle habits, DPs, and low physical activity levels. This study aims to examine the dietary, physical activity, sociodemographic, and lifestyle patterns of Uruguayan State Electrical Company workers (the IN-UTE study). A total of 2194 workers participated in the study, providing information about their sociodemographics, lifestyles, and dietary habits through different questionnaires. To identify DPs from 16 food groups, principal component analysis (PCA) was performed. A hierarchical cluster algorithm was used to combine food groups and sociodemographic/lifestyle variables. Four DPs were extracted from the data; the first DP was related to the intake of energy-dense foods, the second DP to the characteristics of the job, the third DP to a Mediterranean-style diet, and the fourth DP to age and body mass index. In addition, cluster analysis involving a larger number of lifestyle variables produced similar results to the PCA. Lifestyle and sociodemographic factors, including night work, working outside, and moderate and intense PA, were significantly correlated with the dietary clusters, suggesting that working conditions, socioeconomic status, and PA may play an important role in determining DPs to some extent. Accordingly, these findings should be used to design lifestyle interventions to reverse the appearance of unhealthy DPs in the UTE population.

Fulminant ectopic Cushing's syndrome caused by metastatic small intestine neuroendocrine tumour - a case report and review of the literature

Cushing's syndrome (CS) secondary to adrenocorticotropic hormone (ACTH) producing tumours is a severe condition with a challenging diagnosis. Ectopic ACTH-secretion often involves neuroendocrine tumours (NET) in the respiratory tract. ACTH-secreting small intestine neuro-endocrine tumours (siNET) are extremely rare entities barely reported in literature. This review is illustrated by the case of a 75-year old woman with fulminant ectopic CS caused by a ACTH-secreting metastatic siNET. Severe hypokalemia, fluid retention and refractory hypertension were the presenting symptoms. Basal and dynamic laboratory studies were diagnostic for ACTH-dependent CS. Extensive imaging studies of the pituitary and thorax-abdomen areas were normal, while [68Ga]Ga-DOTATATE PET-CT revealed increased small intestine uptake in the left iliac fossa. The hypercortisolism was well controlled with somatostatin analogues, after which a debulking resection of the tumour was performed. Pathological investigation confirmed a well-differentiated NET with sporadic ACTH immunostaining and post-operative treatment with somatostatin analogues was continued with favourable disease control.

Gestational weight gain charts for Latin American adolescents

Monitoring gestational weight gain (GWG) throughout pregnancy among adolescents is important for detecting individuals at risk and timely intervention. However, there are no specific tools or guidelines for GWG monitoring of this group. We aimed to construct GWG charts for pregnant adolescents (10-19 years old) according to pre-pregnancy body mass index (BMI) using a pooled dataset from nine Latin American countries. Datasets from Argentina, Brazil, Chile, Colombia, Mexico, Panama, Paraguay, Peru, and Uruguay collected between 2003 and 2021 were combined after data cleaning and harmonization. Adolescents free of diseases that could affect GWG and who gave birth to newborns weighing between 2,500-4,000 g and free of congenital malformations were included. Multiple imputation techniques were applied to increase the sample size available for underweight and obesity categories. Generalized Additive Models for Location, Scale, and Shape were used to construct the charts of GWG according to gestational age. Internal and external validation procedures were performed to ensure that models were not over-adjusted to the data. The cohort included 6,414 individuals and 29,414 measurements to construct the charts and 1,684 individuals and 8,879 measurements for external validation. The medians (and interquartile ranges) for GWG at 40 weeks according to pre-pregnancy BMI were: underweight, 14.9 (11.9-18.6); normal weight, 14.0 (10.6-17.7); overweight, 11.6 (7.7-15.6); obesity, 10.6 kg (6.7-14.3). Internal and external validation showed that the percentages above/below selected percentiles were close to those expected, except for underweight adolescents. These charts describe the GWG throughout pregnancy among Latin American adolescents and represent a significant contribution to the prenatal care of this group. GWG cut-offs based on values associated with lower risks of unfavorable outcomes for the mother-child binomial should be determined before implementing the charts in clinical practice.

A comprehensive health effects assessment of the use of sanitizers and disinfectants during COVID-19 pandemic: a global survey

COVID-19 has affected all aspects of human life so far. From the outset of the pandemic, preventing the spread of COVID-19 through the observance of health protocols, especially the use of sanitizers and disinfectants was given more attention. Despite the effectiveness of disinfection chemicals in controlling and preventing COVID-19, there are critical concerns about their adverse effects on human health. This study aims to assess the health effects of sanitizers and disinfectants on a global scale. A total of 91,056 participants from 154 countries participated in this cross-sectional study. Information on the use of sanitizers and disinfectants and health was collected using an electronic questionnaire, which was translated into 26 languages via web-based platforms. The findings of this study suggest that detergents, alcohol-based substances, and chlorinated compounds emerged as the most prevalent chemical agents compared to other sanitizers and disinfectants examined. Most frequently reported health issues include skin effects and respiratory effects. The Chi-square test showed a significant association between chlorinated compounds (sodium hypochlorite and per-chlorine) with all possible health effects under investigation (p-value <0.001). Examination of risk factors based on multivariate logistic regression analysis showed that alcohols and alcohols-based materials were associated with skin effects (OR, 1.98; 95%CI, 1.87-2.09), per-chlorine was associated with eye effects (OR, 1.83; 95%CI, 1.74-1.93), and highly likely with itching and throat irritation (OR, 2.00; 95%CI, 1.90-2.11). Furthermore, formaldehyde was associated with a higher prevalence of neurological effects (OR, 2.17; 95%CI, 1.92-2.44). Furthermore, formaldehyde was associated with a higher prevalence of neurological effects (OR, 2.17; 95%CI, 1.92-2.44). The use of sodium hypochlorite and per-chlorine also had a high chance of having respiratory effects. The findings of the current study suggest that health authorities need to implement more awareness programs about the side effects of using sanitizers and disinfectants during viral epidemics especially when they are used or overused.

Study of Food Intake and Physical Activity Patterns in the Working Population of the Uruguayan State Electrical Company (UTE): Design, Protocol and Methodology

Noncommunicable diseases are the main cause of death globally, and most are potentially preventable; they are long term diseases and generally evolve slowly. In Uruguay 64.9% of the population between 25 and 64 years of age are either overweight or obese. The available scientific data show that workplaces are good for developing food-intake interventions for a healthier life. The present study aims to report the design, protocol and methodology for the evaluation of the food intake and physical activity patterns of the Uruguayan State Electrical Company (UTE) workers, as it is distributed across the whole country, and has established associations with overweight and obesity in order to establish institutional strategies to improve the situation. This study uses a population and a cross-sectional, randomized, representative sample of UTE workers with a precision of 3% and a confidence level of 95%. The considered anthropometric variables are weight, height, waist circumference, percentage of fat mass and percentage of visceral fat. A questionnaire on frequency of consumption of different foods and two 24-h dietary recalls (24-h DR) will be performed to evaluate the food intake. Accelerometry will be used to evaluate physical activity, and the International physical activity questionnaire (IPAQ) will be applied. Clinical data will be obtained from the UTE clinical charts. This is the first study of its kind that will be undertaken in Uruguay. It is registered under ClinicalTrials.gov Identifier nº NCT04509908.

Duration of Breastfeeding and Its Relation to Ultra-Processed Products and Sweetened Beverages Intake in Uruguayan Children Under Four Years

Objectives

Longer duration of breastfeeding seems to be associated with healthier eating habits in children. Aim of this study was to determine the association between breastfeeding duration, and the consumption of ultra-processed products and sweetened beverages, in Uruguayan children under 4 years.

Methods

Data used in this descriptive study were obtained in the First National Survey of Child Health, Nutrition and Development of Uruguay (ENDIS), including children under 4 years (n = 3077) recruited in 2013. The interviewed adult was asked about breastfeeding duration, as well as the child´s eating habits through a qualitative survey. Breastfeeding duration was classified as: never, &lt;6 months and ³6 months; and foods as ultra-processed products and sweetened beverages. Children were grouped by age (&lt;24 and ³24 months). Adjusted regression models were tested to evaluate the association of breastfeeding duration with children's intake (yes or no) of ultra-processed and sweetened products, adjusted for maternal age, maternal body mass index and food security (yes or no). Statistical analysis was done with SPSS Statistics version 25.

Results

Prevalence of breastfeeding duration was 44%, 43% and 13% for ³6 month, &lt;6 months and never breastfed, respectively. A quarter of all children consumed habitually sweetened beverages and more than 80% ultra-processed products. Children &lt;6 months did not consume ultra-processed products or sweetened beverages. Therefore, these children were not further analyzed. In children aged 6–23 months there were no associations between breastfeeding duration and consumption of the tested foods (p &gt; 0.05). In children aged 24–47 months, breastfeeding duration ³6 months was associated with lower odds of consuming sweetened beverages (OR:0.62, CI 95%: 0.39–0.98, p = 0.040), and this association remained after covariates adjustment (OR:0.57, CI 95%: 0.36–0.92, p = 0.022). No associations were found between breastfeeding duration and consumption of ultra-processed products in the older children.

Conclusions

Longer breastfeeding duration was associated with a reduced consumption of sweetened beverages, in children between 24 months and four years. No association was found with ultra-processed products.

Funding Sources

Instituto Nacional de Estadística, Uruguay. Grupo de Estudios de Familia, Universidad de la República, Uruguay.

Comparison of Two Criteria of Weight Gain Adequacy During Pregnancy in Relation to Anthropometric Indices in Uruguayan Young Children

Objectives

To compare the relationship between maternal weight gain during pregnancy and anthropometric indices of Uruguayan children under 4 years examined by two different criteria for adequate pregnancy weight gain: Atalah et al. (AEA) widely used in Latin America and Institute of Medicine (IOM).

Methods

Descriptive study of data from the First National Survey of Child Health, Nutrition and Development of Uruguay (ENDIS) of children (n = 1602; age 24.3 ± 10.6 months) recruited in 2013. Weight and height of the children were measured. Child birth weight (BW) and pregnancy weight gain (PregWG) were reported at the interview. PregWG was classified as adequate or excessive according to AEA and IOM criteria. Z scores for weight-for-age (WAZ), height-for-age (HAZ), weight-for-height (WHZ) and body mass index-for-age (BAZ) of the children were obtained from the Growth Patterns of World Health Organization.

Results

Prevalence of excessive PregWG was higher based on AEA (51.2%) compared to IOM (38.9%) criteria (P &lt; 0.001). Excessive PregWG was associated with higher child BW compared to adequate PregWG using both criteria (AEA: 3361 ± 525 g and 3203–550 g, IOM: 3379 ± 543 g and 3224–534 g, respectively) (P &lt; 0.001). Prevalence of macrosomic BW (&gt;4000 g) with excessive PregWG was similar using AEA (10%) and IOM (12%). WAZ was higher with excessive compared to adequate PregWG using AEA (0.52 ± 1.07 and 0.32 ± 1.66, respectively) (P &lt; 0.005) but not different by using IOM (0.51 ± 1.08 and 0.37 ± 1.55, respectively) (P = 0.057). HAZ was lower with excessive compared to adequate PregWG based on AEA (−0.4 ± 1.12 and −0.23 ± 1.10, respectively) (P = 0.001) but not different based on IOM (−0.7 ± 1.15 and −0.18 ± 1.09, respectively) (P = 0.057). WHZ and BAZ did not differ by PregWG categories using AEA or IOM.

Conclusions

Prevalence of excessive weight gain during pregnancy was higher using AEA compared to IOM criteria. However, only subtle differences in the associations between adequacy of pregnancy weight gain and child anthropometric indices were observed when using AEA or IOM criteria.

Funding Sources

Instituto Nacional de Estadística, Uruguay.

Atropisomerism in 3-arylthiazolidine-2-thiones. A combined dynamic NMR and dynamic HPLC study

Sterically hindered 3-arylthiazolidine-2-thiones were prepared by a solvent-free reaction with arylisothiocyanates and 1,4-dithiane-2,5-diol. Atropisomerism was observed in two compounds (3 and 4, aryl = 1-naphthyl and 2-methylnaphth-1-yl), whose rotational energy barriers were measured using dynamic NMR and dynamic HPLC. The experimental analyses were supported by DFT calculations. Thermally stable atropisomers were obtained by dehydration of compounds 3 and 4 and the absolute configuration of the atropisomers of compound 6 was determined by theoretical simulation of the ECD and VCD spectra.

Supernatants of irritable bowel syndrome mucosal biopsies impair human colonic smooth muscle contractility

BACKGROUND

Changes in intestinal motility are likely to contribute to irritable bowel syndrome (IBS) pathophysiology. The aim of the study was to investigate the effects of IBS mucosal supernatants on human colonic muscle contractility.

METHODS

Supernatants were obtained from biopsies of 18 IBS patients-nine with constipation (IBS-C) and nine with diarrhea-predominant IBS (IBS-D)-and nine asymptomatic subjects, used as controls. Colonic circular smooth muscle strips or isolated cells (SMC) were exposed to control or IBS supernatants. Spontaneous phasic contractions on strips and morphofunctional parameters on cells were evaluated in basal conditions and in response to acetylcholine (Ach). Incubation with IBS supernatants was also conducted in the presence of antagonists and inhibitors (namely histamine, protease and prostaglandin antagonists, nuclear factor-kappa B inhibitor, catalase, NADPH oxidase inhibitor, and the cAMP- and/or cGMP-cyclase inhibitors).

KEY RESULTS

Exposure to IBS-C and IBS-D supernatants induced a significant reduction in basal tone and Ach-elicited contraction of muscle strips and a significant shortening and impairment of Ach contraction of SMCs. The NADPH oxidase inhibitor prevented the effect of supernatants, while the protease antagonist only IBS-C effect. No effect was observed with the other antagonists and inhibitors. Dilution of IBS-D supernatants partially restored the effects only on SMCs, whereas dilution of IBS-C supernatants significantly reverted the effects on muscle strips and Ach-elicited response on SMC.

CONCLUSIONS & INFERENCES

Supernatants from mucosal biopsies of IBS patients reduce colonic contractility. The observed impairment was concentration dependent, likely occurring through intracellular oxidative stress damage, involving different neuromotor mechanisms depending on the IBS subtype.

Patología ocular en niños: estudio de validación de un método de cribado en la etapa escolar. Marzo – diciembre 2010, Montevideo, Uruguay

<p><strong>Introducción.</strong></p><p>El “Programa Nacional de Salud Ocular”  tiene por objetivo abordar las causas evitables o tratables de ceguera. En este marco, el Departamento de Medicina Familiar y Comunitaria ha desarrollado actividades de Promoción de salud y Prevención de enfermedades y problemas oculares en la infancia. Esta actividad se planifico y se llevo a cabo en interdisciplina con la participación de estudiantes de grado de medicina, estudiantes de la licenciatura de oftalmología, licenciados en oftalmología y oftalmólogos, y en intersectorialidad con la participación  del Hospital de Ojos, Ministerio de Desarrollo Social y Cámara de Ópticos.</p><p>Este trabajo incorpora la evaluación de las competencias adquiridas por los estudiantes en la realización del cribado de alteraciones visuales (grado de concordancia inter-observador).<strong></strong></p><p><strong>Objetivo.</strong></p><p>Evaluar  validez y seguridad de la aplicación de un método de cribado de patología ocular en escolares y preescolares por estudiantes de medicina en  tres instituciones del Zonal 12 de Montevideo (marzo-diciembre 2010).  <strong></strong></p><p><strong>Metodología.</strong></p><p>Se capacitó a los estudiantes de Medicina con una modalidad blended-learning (combinando clases presenciales con la fase on line) e instancias prácticas  en consultorio.</p><p>Las jornadas de cribado fueron doble ciego siendo los niños evaluados por un estudiante y un licenciado en oftalmología.</p><p>Se exploró sistemáticamente agudeza visual mediante cartilla de Snellen  y alineación ocular por test de Hirschberg.</p><p><strong>Resultados.</strong></p><p>Se estudiaron 196 niños de 5 a 8 años. Requirieron derivación 13.7% por déficit en la agudeza visual y 2.5% por estrabismo.</p><p>La concordancia entre estudiante y Técnicos en relación a la derivación por déficit de la agudeza visual fue  94% y por estrabismos  96%.</p><p>El valor Kappa para  agudeza visual fue de 0,77 y para el estrabismo 0,53.</p><p>La sensibilidad de los estudiantes  fue 88.9% para la agudeza visual y de 100% para el estrabismo.</p><p>La especificidad fue de  94.7 % para agudeza visual y 95.8 % para estrabismo.</p><p>El valor predictivo positivo fue de 72,7 % para la agudeza visual y 38.4 % para estrabismo y el valor predictivo negativo fue de  98.1 % para agudeza visual y 100 % para estrabismo.<strong></strong></p><p><strong>Conclusiones.</strong></p><p>El porcentaje de derivados es similar a trabajos realizados anteriormente. A partir de los resultados del trabajo sería oportuno incorporar la realización del cribado de alteraciones visuales por estudiantes de medicina capacitados, en las instituciones educativas, lo cual optimiza las intervenciones en el primer nivel de atención.<em>. .</em></p>

Contribution of intestinal smooth muscle to Crohn's disease fibrogenesis

Mesenchymal cells transdifferentiation and extracellular matrix deposition are involved in the fibrotic process of Crohn's disease (CD). Mesenchymal smooth muscle cells (SMCs) de-differentiation, driven by Platelet-derived growth factor (PDGF) that counteracts Transforming growth factor (TGF-β) has been studied in vascular muscle. The role of SMCs in intestinal fibrogenesis is still not clearly elucidated. Aim of the study was to evaluate the possible myogenic contribution to CD fibrotic process through the comparative analysis of histological, morphometric and molecular alterations occurring in human smooth muscle. Full thickness specimens were obtained from CD (non-involved and stenotic tracts) and healthy (control) ileum. Tissues were processed for histological and immunohistochemical (IHC) analyses and SMCs were isolated from the muscularis propria for morphofunctional and molecular (qPCR) analyses. CD stenotic ileum showed a significant increased thickness of all layers compared to CD non-involved and control ileum. IHC revealed an overexpression of α-smooth muscle actin and collagens I-III throughout all intestinal layers only in stenotic tracts. The two growth factors, PDGF and TGF-β, showed a progressive increase in expression in the muscle layer from CD non-involved to stenotic tracts. Freshly isolated SMCs presented alterations in CD non-involved tracts that progressively increased in the stenotic tracts consisting in a statistical increase in mRNA encoding for PDGF-β and collagen III, paralleled to a decrease in TGF-β and Tribbles-like protein-3 mRNA, and altered morphofunctional parameters consisting in progressive decreases in cell length and contraction to acetylcholine. These findings indicate that intrinsic myogenic alterations occur in CD ileum, that they likely precede stricture formation, and might represent suitable new targets for anti-fibrotic interventions.

Double burden of undernutrition and obesity in Uruguay

BACKGROUND

Uruguay is at an advanced stage of the epidemiologic transition; like other Latin American countries, it bears a nutritional double burden composed of undernutrition and overweight or obesity.

OBJECTIVES

The aim was to estimate whether a double burden of nutritional problems exists in Uruguay and to identify if governmental programs and policies for nutrition take this double burden into account.

DESIGN

Existing studies were reviewed, and other data were processed specifically for the purpose of this article. Several data sources were used to include a broad, comprehensive population range.

RESULTS

The prevalence of stunting in children aged <2 y is 10.9%. There is a high frequency of obesity, which increases with age (9.5% in children <2 y old, 18.8% in those aged 6 y, 20.4% in those aged 11 y, 26.6% in those aged 13-15 y, and 35.3% in adults). In addition, 13.8% of women start pregnancy underweight and the rate of obesity increases during pregnancy from 36.7% at the beginning to 46.5% at the end. Anemia is very frequent in the selected population we examined, as follows: 31% of children <2 y old and 20.9% of pregnant women in their third trimester. An obese mother with a stunted child are present in 6.3% of households; 1.9% of stunted children are obese at age 6 y and 3.1% are obese at the age of 11. Multiple logistic analysis applied to children <2 y showed an association between stunting and obesity (OR: 2.0; 95% CI: 1.2, 3.6).

CONCLUSIONS

The data suggest that there is a nutritional double burden in Uruguay. This nutritional burden is similar to that of other countries in the region. This important public issue should be tackled, and it should be addressed in early infancy.

Zinc in plasma and breast milk in adolescents and adults in pregnancy and pospartum: a cohort study in Uruguay

OBJECTIVE

To assess if age is a risk factor for low zinc nutritional status in pregnancy, postpartum and in breast milk concentration, and the association between mother zinc plasma level with zinc milk concentration.

DESIGN

Cohort study comparing adolescents with adult women, with < 14 weeks of gestation at first prenatal care. Socio demographic and plasma zinc data were collected at that moment and at postpartum time (4 + 1 month). Milk zinc concentrations were also measured at 4 th month postpartum.

SETTING

Women were recruited from 16 public primary health care services in Uruguay Subjects: 151 adolescents and 161 adult women.

RESULTS

Adolescent average plasma zinc at < 14 weeks of gestation was 84.4 ± 3.6 ug /dl and did not differ significantly from that for adult women (85.2 ± 13.6 ug/dl). Prevalence of hypozincemia was relatively low with but with no difference by age (14.6% in adolescents and 12.3% in adults). Zinc concentrations in breast milk were similar for adolescents, 1.24 mg. /L (CI 1.06 to 1.44) and adult women, 1.27 mg./L (CI .1.0-1.46). There was no correlation between plasma zinc and breast milk zinc concentrations in adults and a weak correlation in adolescents (- 0.27, P <0.05).

CONCLUSIONS

Prevalence of hypozincemia in pregnancy was relatively low but similar in adolescents and adult women. Neither pregnancy nor age had negative consequences over postpartum plasma zinc, nor over breast milk zinc concentrations. No correlation was found between mother s plasma zinc and breast milk levels.

Role of endoscopic sphincterotomy of the minor papilla in pancreas divisum

BACKGROUND

Pancreas divisum (PD) is a common anatomical variant of the pancreatic duct system. Only a little percentage of patients with this altered anatomy develop symptoms: acute recurrent pancreatitis (ARP), chronic pancreatitis (CP) and pancreatic-type pain alone. These have been supposed to arise from an obstruction to outflow of the pancreatic dorsal duct due to a stenosis of the minor papilla. Endoscopic sphincterotomy of the minor papilla (MiES) can be considered an effective treatment for patients with PD and ARP supported by stenosis or obstruction of the minor papilla. On the other hand, the access through the minor papilla is essential for therapeutic pancreatic endoscopy in patients with PD and CP, but the effectiveness of MiES in these patients is extremely controversial.

MATERIALS AND METHODS

Aim of this brief review has been to evaluate the short and long-term effects of endoscopic pancreatic interventions in patients affected by symptomatic PD who underwent therapeutic endoscopic retrograde cholangiopancreatography (ERCP) with pancreatic sphincterotomy of the minor papilla (MiES). The main literature database was Medline (1966-2013).

RESULTS

Data come from a personal overview of articles emerging from the same search strategy.

CONCLUSIONS

Nowadays, when endoscopic pancreatic drainage is indicated in patient with symptomatic PD, access through the minor papilla (MiP) is required. Therapeutic endoscopic interventions provide less invasive alternatives to the surgical approach.

Lactobacillus rhamnosus protects human colonic muscle from pathogen lipopolysaccharide-induced damage

BACKGROUND

Lactobacillus species might positively affect gastrointestinal motility. These Gram-positive bacteria bind Toll-like receptor 2 (TLR2) that elicits anti-inflammatory activity and exerts protective effects on damage induced by lipopolysaccharide (LPS). Whether such effect occurs in gastrointestinal smooth muscle has not been established yet. Aim of this study was to characterize the effects of Lactobacillus rhamnosus GG (LGG) and of supernatants harvested from LGG cultures on human colonic smooth muscle and to explore their protective activity against LPS-induced myogenic morpho-functional alterations.

METHODS

The effects of LGG (ATCC 53103 strain) and of supernatants have been tested on both human colonic smooth muscle strips and isolated cells in the absence or presence of LPS obtained from a pathogenic strain of Escherichia coli. Their effects on myogenic morpho-functional properties, on LPS-induced NFκB activation, and on cytokine production have been evaluated. Toll-like receptor 2 expression has been analyzed by qPCR and flow cytometry.

KEY RESULTS

Lactobacillus rhamnosus GG exerted negligible transient effects per se whereas it was capable of activating an intrinsic myogenic response counteracting LPS-induced alterations. In particular, both LGG and supernatants significantly reduced the LPS-induced morpho-functional alterations of muscle cells, i.e. cell shortening and inhibition of contractile response. They also hindered LPS-induced pro-inflammatory effects by decreasing pro-inflammatory transcription factor NFκB activation and pro-inflammatory cytokine IL-6 secretion, and restored the secretion levels of anti-inflammatory cytokine IL10.

CONCLUSIONS & INFERENCES

Taken together these data demonstrate that LGG protects human colonic smooth muscle from LPS-induced myogenic damage and might be beneficial on intestinal motor disorders due to bacterial infection.

Myogenic regional responsiveness to cholinergic and vipergic stimulation in human colon

BACKGROUND

Differences in the actions of enteric neurotransmitters on colonic circular and longitudinal muscle layers have not been clearly determined, nor the possible existence of intrinsic myogenic phenotypes that might contribute to regional differences in human colon motor activity. The aim of this study was to analyze the direct pharmaco-mechanical coupling of carbachol (CCh) and vasoactive intestinal polypeptide (VIP) on human colonic smooth muscle strips and cells.

METHODS

Circular and longitudinal muscle strips and cells were obtained from 15 human specimens of ascending and sigmoid colon. Both isometric tension on muscle strips and contraction and relaxation on cells were measured in response to increasing CCh and VIP concentrations.

KEY RESULTS

Circular muscle strips of ascending colon were more sensitive to the effect of CCh than that of sigmoid colon, EC(50) values being, respectively, 4.15μmolL(-1) and 8.47μmolL(-1) (P<0.05), although there were no differences in maximal responses. No regional differences were observed in longitudinal muscle strips or in smooth muscle cells. Maximal responses to CCh were higher on circular than longitudinal muscle strips and cells throughout the colon. A greater sensitivity to VIP was observed in ascending colon compared with sigmoid colon, both in circular (EC(50:) 0.041 and 0.15μmolL(-1) , respectively, P<0.01) and longitudinal (EC(50:) 0.043 and 0.09μmolL(-1) , respectively, P<0.05) strips, and similar differences were observed in longitudinal smooth muscle cells (EC(50:) 44.85 and 75.24nmolL(-1) , respectively, P<0.05).

CONCLUSIONS & INFERENCES

Regional myogenic differences in pharmaco-mechanical coupling between the enteric neurotransmitters and smooth muscle contribute to the complex regional motor patterns of human colon.

Chronic constipation in hypercalcemic patients with primary hyperparathyroidism

BACKGROUND

Chronic constipation (C), among gastrointestinal symptoms, is commonly associated with primary hyperparathyroidism (PHPT) and probably attributable to hypercalcemia.

OBJECTIVE OF THE STUDY

To evaluate in patients affected with PHPT the prevalence of C utilizing a validated questionnaire and the current prevalence of C compared to that observed in the past and to evaluate the relationship between C and the severity of PHPT.

METHODS

55 outpatients affected with PHPT, admitted to our Department of Internal Medicine and Medical Specialities in the years (2006-2009) were studied (group 1: 50 postmenopausal women and 5 men, mean age 61.9 +/- 9.4 years), together with 55 sex and age matched controls (group 2). Also considered were a group of PHPT patients observed, in the same ambulatory, during the years '70-'80 (group 3). A questionnaire, Rome II criteria, was administered and used to define C, whereas only anamneses were used to define C in group 3.

RESULTS

The prevalence of C in patients with PHPT was 21.8% in group 1 vs 12.7% in group 2 (n.s.) and 32.7% in group 3. There is a decreasing trend in the prevalence of C in patients with PHPT as observed from 1970-89 to 2006-2009 (p < 0.05). The reduction of C was associated together with a significant reduction in the serum calcium level (p < 0.001). The presence of C vs its absence in patients with PHPT is characterized by higher values of calcemia (p < 0.001), ionized calcium (p < 0.001), and parathyroid hormone (p = 0.019).

CONCLUSION

The actual prevalence of C in patients with PHPT is not significantly different from that found in the control group and is decreasing with respect to the past years. Moreover, C seems to be associated with the severity of the disease rather than with the diagnosis of PHPT per se.

Exocrine gastric secretion and gastritis: pathophysiological and clinical relationships

Gastric exocrine secretion, both acid and non-acid, is required for micronutrients absorption, such as iron, calcium and vitamin B12, drugs absorption, protein digestion. Clinical presentation of a gastric secretion impairment might be then characterized by the presence of both gastrointestinal and non-gastrointestinal specific symptoms (i.e. anemia) or to a non-response to therapies. The main factor that impairs gastric exocrine secretion homeostasis is mucosal chronic inflammation that principally occurs after colonization by Helicobacter pylori (Hp). The extent and distribution of gastritis ultimately determine the clinical outcome linked to differences in gastric acid secretion status, the involvement of gastric body leading to a decrease in gastric exocrine secretion with possible progression to mucosal atrophy towards cancer. A correct clinical strategy in the management of Hp infected patients should be then to early identify body involvement, a diagnosis generally missed in that body biopsies are not routinely performed. The use of gastric serological markers, gastrin and pepsinogens, are helpful in suspecting the presence of mucosal atrophy but their diagnostic accuracy for non-atrophic chronic gastritis topography is not adequate despite a good specificity due to the low sensitivity, of all the available biomarkers. Gastric serology associated to anemia/iron-deficiency screening might nevertheless been helpful in the framing of patients that undergo endoscopy in order to highlight the need of extensive mucosal biopsies sampling.

Correlation between faecal calprotectin and magnetic resonance imaging (MRI) in the evaluation of inflammatory pattern in Crohn's disease

BACKGROUND

Calprotectin, a major cytosolic protein of neutrophils, is increased in inflammatory bowel disease (IBD) and may be considered a suitable marker of intestinal inflammation. Abdominal MRI is becoming more frequently used for the evaluation of IBD patients. Aim of this study was to investigate the role of MRI in IBD for the assessment of disease activity in comparison with faecal calprotectin levels.

PATIENTS AND METHODS

Twenty-four consecutive hospitalized pts (12 F, 12 M, median age: 56; range: 22-77) with a proven diagnosis of CD were studied. At the time of the MRI examination, pts provided a single stool sample for calprotectin measurement. Calprotectin was measured by ELISA (Calprest(R)). Pathological values were considered more than 50 microg/g. All pts underwent MRI, performed at 1.5 T, with HASTE T2w with and without fat-saturation, FLASH T1w fat-saturated sequences pre and post iv injection of 0.1 ml/kg of Gadolinium. Presence, degree and length of wall inflammation were evaluated. The MRI degree of wall inflammation was graded with a 0-3 scoring system (0=absent 1=light 2=moderate 3=severe) by considering findings observed on T1 post Gd and T2 fat-suppressed images, as well as the degree of wall thickness. The length of extension was considered as less than 15 cm, between 15 cm and 30 cm, or more than 30 cm. Spearman's correlation coefficient was used to evaluated differences in calprotectin levels among the groups obtained by MRI findings.

RESULTS

Grade 0 MRI was found in 1 pt with a faecal calprotectin measurement of 206.25 microg/g; Grade 1 MRI was found in 4 pts with a median faecal calprotectin of 100 microg/g (5-325); Grade 2 MRI was found in 10 pts with a median faecal calprotectin of 243.75 microg/g (7.5-606.25); Grade 3 MRI was found in 9 pts with a median faecal calprotectin of 1012.5 microg/g (30-1268.8). A trend of positive correlation was therefore found between MRI scores of activity and calprotectin levels (p less than 0.0001) and between MRI scores of thickening of intestinal involvement and calprotectin levels (p = 0.005). No apparent correlation was observed between faecal calprotectin concentration and length.

CONCLUSIONS

Data presenting show that faecal calprotectin levels well correlate with the degree of mucosal inflammation are in agreement with previous studies. Considering the correlation obtained between calprotectin level and MRI findings, we believe that MRI is helpful in assessing and monitoring the degree of disease in Crohn's disease.

Microscopic colitis: a concise review

Microscopic colitis is an increasingly common cause of chronic watery diarrhoea, and often a causes of abdominal pain of unknown origins. The increase of interest for this clinical entity is due to a misdiagnosis of any symptoms that have been frequently attributed to diarrhea-predominant irritable bowel syndrome, often for many years before diagnosis. Presumably, most estimates of incidence and prevalence understate the true frequency of microscopic colitis for this reason. The aim of this paper is to evaluate the importance of microscopic colitis as cause of chronic non bloody diarrhoea, on the basis of literature review. These kind of colitis are characterized by normal colonic mucosa at endoscopy or barium enema but with increased inflammation in colonic biopsies. Microscopic colitis consists of two main subtypes, collagenous colitis and lymphocytic colitis, distinguished by the presence of absence of a thickened subepithelial collagen band. Several models of pathogenesis has been proposed but no convincing mechanism has been identified, although is difficult to characterize this clinical entity as an independent phenomenon or a simple manifestation or related factors active to induce microscopic changing in the colonic mucosa. A rational approach to therapy does not exist and was conduct with several types of drugs after the exclusion of other causes, commonly characterized by this symptoms and the definitive histological assessment in the biopsies specimens. In the majority of cases this condition tends to follow a self-limited course but potentially can assume the characteristics of relapsing course with the necessity to a chronic therapy. Several long-term follow-up studies excluded a possible progression to neoplastic malignancies of microscopic colitis.

High efficacy of bismuth subcitrate for Helicobacter pylori eradication in pangastritis

BACKGROUND

The influence of gastritis patterns in Helicobacter pylori eradication rates has been poorly investigated.

AIMS

To compare the efficacy of bismuth or proton pump inhibitors triple therapy for H. pylori eradication in pangastritis.

PATIENTS AND METHODS

One hundred and eight patients with pangastritis were assigned to either lansoprazole 30 mg once a day (n=54) or bismuth 240 mg bis in die (n=54) for 14 days combined, for the first week, with amoxicillin 1g plus metronidazole 250 mg tris in die. Eradication was confirmed by (13)C-urea breath test.

RESULTS

With bismuth, successful eradication was observed in 75.9% (41/54) in the intention-to-treat analysis and 78.8% (41/52) in the per-protocol analysis. With lansoprazole, the eradication rates were respectively 46.3% (25/54) and 51.0% (25/49). Bismuth had a significant higher efficacy according to both intention-to-treat analysis (p=0.0029) and per-protocol analysis (p=0.0038) with OR of 3.66 (95% CI: 1.61-8.32) and 3.58 (95% CI: 1.50-8.54) respectively. At regression analysis, the only independent variable affecting eradication was the type of regimen (p=0.026) with an OR of 3.31 (95% CI: 1.16-9.44).

CONCLUSIONS

In pangastritis patients, bismuth is more effective than PPI in first-line eradication. For improving the overall eradication rates, an evaluation of gastritis extent might need to be considered.

Vasoactive intestinal peptide receptor subtypes and signalling pathways involved in relaxation of human stomach

Vasoactive intestinal peptide (VIP) relaxes smooth muscle by interacting with receptors coupled to cAMP- or cGMP-signalling pathways. Their relative contribution to human gastric relaxation is unknown. This study aimed at investigating, in terms of biological activity, receptor expression and related signalling pathways, the action of VIP separately on the human fundus and the antrum. VIP caused greater relaxation of smooth muscle cells (SMC) and strips of the antrum presenting on the former a higher efficacy and potency (ED(50): 0.53 +/- 0.17 nmol L(-1)) than on the fundus (ED(50): 3.4 +/- 1.4 nmol L(-1)). On both fundus and antrum strips, its effect was tetrodotoxin insentitive. Reverse transcriptase-polymerase chain reaction analysis showed the sole expression of VPAC2 and natriuretic peptide clearance receptors, with VPAC2 being more abundant in the antrum. Functional regional differences in receptor-related signalling pathways were found. Activation of the cAMP-pathway by forskolin or its inhibition by adenylate cyclase (2'5'-dideoxyadenosine) or kinase (Rp-cAMPs) inhibitors had more pronounced effects on antrum SMC. Activation of the cGMP-pathway by sodium nitroprusside or its inhibition by guanylate cyclase (LY83583) or kinase (KT5823) inhibitors had more effects on fundus SMC, on which a higher expression of endothelial nitric oxide synthase was found. In conclusion, regional differences in VIP action on human stomach are related to distinct myogenic properties of SMC of the antrum and the fundus.

Somatostatin receptor subtypes mediate contractility on human colonic smooth muscle cells

This study demonstrates the expression of functional somatostatin receptor (sstr) subtypes in human circular and longitudinal colonic smooth muscle cells (SMC). Native somatostatin (SS) and sstr subtype-specific analogues were used to characterize the sstr subtypes present in both cell types by contraction/relaxation studies. Qualitative and quantitative mRNA analysis and immunohistochemistry of sstr subtypes were also carried out. sstr subtype 2 mRNA was expressed in circular SMC, and various levels of subtypes 1, 2 and 3 mRNA were expressed in longitudinal colonic SMC. Native SS and each subtype-specific analogue exerted a modest, but significant, contraction, although inhibition of carbachol-induced contraction (relaxation) was the main effect on SMC from both layers. CH-288, a sstr subtype 1-specific analogue, and octreotide, a sstr subtype 2-specific analogue, were the most effective relaxant analogues on longitudinal and circular SMC, respectively. sstr subtypes display a distinct expression pattern on human colonic SMC; on circular SMC, subtype 2 is the only sstr, whereas sstr subtypes 1, 2 and 3 are expressed on human SMC isolated from the longitudinal layer. The contractile effects of SS are mediated through sstr subtype 2 and sstr subtype 1 on circular and longitudinal human colonic SMC, respectively.

Optimisation of isolation of richly pure and homogeneous primary human colonic smooth muscle cells

BACKGROUND

Inherent properties of gastrointestinal smooth muscle can be assessed using isolated cell suspensions. Currently available isolation techniques, based on short 2-h enzymatic digestion, however, present the disadvantage of low cellular yield with brief viability. These features are an important limiting factor especially in studies in humans in which tissue may not be available daily and mixing of samples is not recommended.

AIMS

To optimise the isolation procedure of cells from human colon to obtain a richly pure primary smooth muscle cell preparation.

METHODS

Slices of circular muscle layer, obtained from surgical specimens of human colon, were incubated overnight in Dulbecco's modified eagle's medium supplemented with antibiotics, foetal bovine serum, an ATP-regenerating system and collagenase. On the following day, digested muscle strips were suspended in HEPES buffer, and spontaneously dissociated smooth muscle cells were harvested and used either immediately or maintained in suspension for up to 72 h. Cell yield, purity, viability, contractile responses, associated intracellular calcium signals and RNA and protein extraction were evaluated and compared to cell suspensions obtained with the current short digestion protocol.

RESULTS AND CONCLUSION

The overnight isolation protocol offers the advantage of obtaining a pure, homogeneous, long-life viable cell suspension that maintains a fully differentiated smooth muscle phenotype unchanged for at least 72 h and that allows multiple functional/biochemical studies and efficient RNA extraction from a single human specimen.

Utility of combined use of plasma levels of chromogranin A and pancreatic polypeptide in the diagnosis of gastrointestinal and pancreatic endocrine tumors

BACKGROUND

Chromogranin A (CgA) is considered the most accurate marker in the diagnosis of gastro-entero-pancreatic (GEP) endocrine tumors. Pancreatic polypeptide (PP) has also been proposed to play this role, but then not used due to its low sensitivity. The aim of the present study was to determine whether the assessment of PP would improve the diagnostic reliability of CgA in patients with GEP tumors.

PATIENTS AND METHODS

Both markers were assessed in 68 patients [28 functioning (F), 40 non functioning (NF)]. Twenty-seven patients disease-free (DF) after surgery, and 24 with non-endocrine tumors (non-ETs) were used as control groups.

RESULTS

CgA sensitivity was: 96% in F, 75% in NF, 74% in pancreatic, and 91% in gastrointestinal (GI) tumors. Specificity was 89% vs DF, and 63% vs non-ETs. PP sensitivity was: 54% in F, 57% in NF, 63% in pancreatic, and 53% in GI tumors. Specificity was 81% vs DF, and 67% vs non-ETs. By combining the two markers a significant gain in sensitivity vs CgA alone was obtained: overall in GEP tumors (96% vs 84%, p = 0.04), in NF (95% vs 75%, p = 0.02), and in pancreatic (94% vs 74%, p = 0.04). More specifically, a 25% gain of sensitivity was obtained in the subgroup of NF pancreatic tumors (93% vs 68%, p = 0.04).

CONCLUSION

The combined assessment of PP and CgA leads to a significant increase in sensitivity in the diagnosis of GEP tumors, particularly in pancreatic NF.

Contribution of NK3 tachykinin receptors to propulsion in the rabbit isolated distal colon

The role of NK3 receptors in rabbit colonic propulsion has been investigated in vitro with the selective agonist, senktide, and two selective antagonists, SR142801 and SB222200. Peristalsis was elicited by distending a rubber balloon with 0.3 and 1.0 mL of water leading to a velocity of 2.2 and 2.8 mm s-1, respectively. At concentrations of 1 nM, senktide inhibited propulsion evoked by both distensions (range 25-40%), whereas at 6 and 60 nmol L-1 facilitated 'submaximal' propulsion by 30%. In the presence of Nomega-nitro-L-arginine (L-NNA, 200 micromol L-1), which per se caused a slight prokinetic effect, 1 nmol L-1 senktide markedly accelerated propulsion (range 35-50%). Hexamethonium (200 micromol L-1) had minor effects on propulsion. In its presence, 60 nmol L-1 senktide significantly inhibited propulsion induced by both stimuli (range 20-50%). SR142801 (0.3, 3 nmol L-1) and SB222200 (30, 300 nmol L-1) facilitated 'submaximal' propulsion (range 20-40%). Conversely, higher antagonist concentrations (SR142801: 30, 300 nM; SB222200: 1, 10 micromol L-1) inhibited propulsion to both distensions by 20%. A combination of SR142801 (300 nmol L-1) plus hexamethonium (200 micromol L-1) induced an approximately four-fold greater inhibition of propulsion than that induced by SR142801 alone. In conclusion, in the rabbit-isolated distal colon, a subset of NK3 receptors located on descending pathways mediates an inhibitory effect on propulsion by activating a NO-dependent mechanism. Another subset of NK3 receptors, located on ascending pathways mediates a facilitative effect involving a synergistic interaction with cholinergic nicotinic receptors.

Efficacy of gluten-free diet alone on recovery from iron deficiency anemia in adult celiac patients

OBJECTIVE

Iron deficiency anemia has been reported as the most frequent extraintestinal symptom in adult celiac disease. Prospective studies on the effect of gluten-free diet on recovery from iron deficiency anemia are lacking. The aim of this study was to verify in adult patients with celiac disease the efficacy of and the time course of recovery from iron deficiency anemia by a gluten-free diet alone.

METHODS

We studied 190 consecutive adult patients with iron deficiency anemia, screened for celiac disease by duodenal biopsies. New diagnosed celiac patients were invited to follow a gluten-free diet alone without iron supplementation. After 6 months of diet, duodenal biopsies were performed and hematological tests were repeated at 6, 12, and 24 months.

RESULTS

Celiac disease was diagnosed in 26 (24 women, 2 men; 13.7%) adult patients. After 6 months of gluten-free diet 14 of 18 (77.8%) female patients recovered from anemia, but only 5 of 18 (27.8%) reversed from iron deficiency. At 12-month control all but one patient (94.4%) recovered from anemia and 9 patients (50%) from iron deficiency. After 24 months of diet, only the patient who did not recover from anemia at 12-month control was still anemic, whereas 10 patients (55.5%) reversed from iron deficiency. A significant inverse correlation (r = -0.7141, p = 0.0003) between increase of Hb concentrations and decrease of individual histological scores of duodenitis was observed.

CONCLUSIONS

A screening for celiac disease should be carried out in adult patients with iron deficiency anemia. Recovery from anemia occurs between 6 and 12 months on a gluten-free diet alone as a consequence of normalization of histological alterations of the intestinal mucosa.

Regional differences in signalling transduction pathways among smooth muscle cells from rabbit colon

Smooth muscle cells (SMC) from the circular muscle layer of rabbit colon, taken from the proximal and distal regions that are known to have different physiological and motor activities, were used to highlight distinct regional intrinsic myogenic properties and to investigate the correlations between receptor and signalling transduction pathways. Contractile agonists were shown to be more potent on proximal than on distal SMC in inducing contraction and intracellular Ca(2+) increase. Concentration-response curves of agonists-induced Ca(2+) increase were constantly shifted to the right, though remaining parallel, with respect to contraction curves, independently of the region analysed. Using agents activating different steps of cAMP-or cGMP-mediated intracellular cascades, main regional differences were revealed as far as relaxation was concerned. Relaxation of proximal SMC was found to be essentially cGMP mediated, while that of distal SMC was cAMP mediated. In conclusion, the motor patterns of the two regions appear to be influenced by distinct regional biochemical characteristics that are intrinsic to colonic SMC.

Progression from homologous to heterologous desensitization of contraction in gastric smooth muscle cells

Acute desensitization of contraction and its relative mechanisms have been studied in smooth muscle cells isolated from guinea pig stomach. Desensitization was induced by pre-exposure of the cells to one of the excitatory neuropeptides linked to the phospholipase C intracellular cascade, i.e., cholecystokinin (CCK), gastrin-releasing peptide, and Substance P. Desensitization was homologous after a 30-s pre-exposure and heterologous if pre-exposure lasted for 5 min or longer. Homologous desensitization was studied in a more detailed way after pre-exposure to CCK. Preincubation with increasing concentrations of CCK (10 pM-1 microM) induced a progressive rightward shift of the dose-response curves associated with both a decrease in potency (ED50 4.5 pM-2.2 nM) and a maximum response that were not related to a modification of response kinetics. After brief pre-exposure to 1 nM CCK (Dmax), an inhibition of contraction was observed in response to an identical dose of CCK (45.1 +/- 8.6%), the decreased response being associated with an inhibition of inositol phosphates and [Ca++]i mobilization. Both inositol trisphosphate (InsP3)-induced contraction and [Ca++]i mobilization were inhibited to a lesser extent than CCK-induced responses. Any longer pre-exposure of cells to one of the above-mentioned neuropeptides caused heterologous desensitization, with an observed inhibition of contraction in response to all tested agonists (CCK, 60.3 +/- 5.9%; gastrin-releasing peptide: 56.7 +/- 3. 5%; Substance P, 60.6 +/- 6.5%). A similar decrease was observed in InsP3-induced contractions resulting in a desensitization of the InsP3 response as well. Full recovery of contractile responses appeared within 30 min from the end of preincubation, thus indicating that degradation of membrane receptors did not occur. Although pre-exposure of the cells to protein kinase C inhibitor GF109203X did not modify CCK-induced homologous desensitization, it blocked CCK-induced heterologous desensitization. This study demonstrates that excitatory phospholipase C-coupled enteric neuropeptides induce a time-dependent homologous as well as heterologous desensitization of smooth muscle contraction occurring at receptor and postreceptor levels.

Human circular colonic smooth muscle cells possess active somatostatin receptors

BACKGROUND & AIMS

Somatostatin alters in vivo colonic motility in different species including humans. Few data are available on a cellular basis that could explain the effects of somatostatin on human colon motility. To address these issues we studied the effects of somatostatin on isolated human circular colonic smooth muscle cells to establish whether its actions are directly or neurally mediated.

METHODS

Circular smooth muscle cells were prepared by enzymatic digestion from surgical specimens of human colon (Sigma) and resuspended in HEPES buffer containing protease inhibitors.

RESULTS

Cholecystokinin (1 nM), carbachol (30 nM) and KCl (20 mM) each caused a contraction of 17%, 16.5% and 15%, respectively. 1 microM of either somatostatin-14, somatostatin-28 or SMS 201-995 alone were able to produce a contraction of 5.1%, 5.7%, and 6.8%, respectively. When smooth muscle cells were preincubated with each of the above-mentioned somatostatin analogs, cholecystokinin-mediated contraction was dose-dependently inhibited only in the presence of antiproteases. The half-maximal effective concentration (EC50) for somatostatin-14, somatostatin-28 and SMS 201-995 were similar (3.5, 5.6, 3.2 nM, respectively).

CONCLUSIONS

Somatostatin acts directly on human circular colonic smooth muscle cells through specific somatostatin receptors. SMS 201-995, a somatostatin receptor subtype-2 preferring analogue, shows a high affinity in inhibiting cholecystokinin-mediated contraction, suggesting the presence of somatostatin receptor subtype-2 on human circular colonic smooth muscle cells.

Colonic smooth muscle cells possess a different subtype of somatostatin receptor from gastric smooth muscle cells

Somatostatin (SS) alters colonic motility. To investigate whether SS has a direct effect on colonic smooth muscle cells, we prepared isolated muscle cells from the descending guinea pig colon and compared the effects of SS with those on isolated gastric smooth muscle cells. In gastric cells, SS had no effect on carbachol-induced contraction, whereas in colonic cells it caused inhibition. In colonic muscle cells, SS-28 caused >85% inhibition of contraction by cholecystokinin octapeptide (CCK-8), bombesin, 12-O-tetradecanoylphorbol-13-acetate, and ionomycin, whereas it had no effect on contraction by these agents in gastric cells. In gastric cells, SS inhibited relaxation. Three synthetic SS analogs had different relative affinities for causing effects in gastric and colonic cells. Pertussis toxin inhibited the action of SS-28 in each muscle cell type by 50-75%. SS-28 alone had a small contractile effect on cells from the circular layer of the colon. SS-28 inhibited carbachol-induced contraction in colonic cells from both the longitudinal and circular layers. These results demonstrate that the action of SS differs in colonic and gastric smooth muscle cells. SS inhibits contractants in colonic cells and relaxants in gastric cells. In colonic cells, SS has a weak contractile effect due to an effect on circular muscle cells and an inhibitory effect on cells from both longitudinal and circular layers. A different SS receptor subtype mediates the actions of SS in colonic and gastric muscle cells. In both cell types, the actions of SS are mediated by pertussis toxin-sensitive and -insensitive G proteins.

Modulation of cholecystokinin activity by albumin

We found that a variety of cholecystokinin (CCK) receptor ligands bind to bovine serum albumin (BSA). This binding was rapid, fully reversible, temperature independent, of low affinity, and specific for BSA; it depended on the concentration of BSA, the chemical structure of the ligand, and the chemical composition of the incubation medium. BSA also decreased the binding of 125I-labeled CCK octapeptide (125I-CCK-8) to CCK receptors on pancreatic acini and membranes but increased the potency with which CCK-8 inhibited binding of 125I-CCK-8. These counterintuitive findings appeared to result from BSA altering the affinities of CCK-8 for different affinity states of the pancreatic CCK receptor. An alternate hypothesis is that BSA increased the efficacy of CCK-8 such that it bound to receptors and also caused biochemical changes in other receptors that reduced their ability to bind 125I-CCK-8. BSA enhanced the ability of CCK-8 to stimulate amylase secretion from pancreatic acini and to cause contraction of dispersed gastric smooth muscle cells. Thus, CCK can bind to BSA, and the BSA-CCK complex has substantially different activities from the free, uncomplexed hormone.

Intracavitary cisplatin (CDDP) in the treatment of metastatic pericardial involvement from breast and lung cancer

Seven patients with lung cancer and two with breast cancer developed a symptomatic pericardial effusion and were treated with intrapericardial cisplatin (CDDP). In all of the patients, cytological confirmation of metastatic effusion was achieved. A single cycle with 10 mg of cisplatin diluted in 20 ml of normal saline was administered for five consecutive days via an intrapericardial catheter. Control of recurrent effusions was obtained in eight of the nine patients. No significant side-effects were observed.

Inhibition of IP3 and IP3-dependent Ca2+ mobilization by cyclic nucleotides in isolated gastric muscle cells

The mechanisms by which cAMP and cGMP and agents that stimulate one (isoproterenol and nitroprusside) or both cyclic nucleotides (VIP) decrease cytosolic free Ca2+ ([Ca2+]i) and inhibit contraction were examined in dispersed, intact, and saponin-permeabilized gastric muscle cells. In these cells, the [Ca2+]i transient responsible for initial contraction is mediated by inositol 1,4,5-trisphosphate (IP3)-dependent Ca2+ release (K. N. Bitar, P. G. Bradford, J. W. Putney, Jr., and G. M. Makhlouf, Science Wash. DC 232: 1143-1145, 1986, and J. Biol. Chem. 261: 16591-16596, 1986). In intact muscle cells, dibutyryl cAMP and all three relaxant agents inhibited contraction, [Ca2+]i, and net Ca2+ efflux (i.e., Ca2+ release) in a concentration-dependent fashion. In permeabilized muscle cells, cAMP, cGMP, and all three relaxant agents 1) inhibited cholecystokinin (CCK)-induced IP3 production (maximal 38-48%), 2) inhibited CCK- and IP3-induced Ca2+ efflux (maximal 55-59%) and contraction (maximal 59-66%), and 3) stimulated Ca2+ uptake (maximal 25-30%), in a concentration-dependent fashion. cAMP and cGMP were equipotent inhibitors of IP3 production and of CCK- and IP3-induced Ca2+ efflux and contraction, whereas cGMP was distinctly more potent as a stimulant of Ca2+ uptake. For all functions, maximal effects induced by cAMP and cGMP were similar to those induced by the three relaxant agents. Inhibition of Ca2+ release was the main determinant of inhibition of contraction; stimulation of Ca2+ uptake was relatively minor (< 5% of Ca2+ efflux). Decrease in IP3 production did not contribute to inhibition of Ca2+ efflux and contraction since inhibition of IP3-induced Ca2+ efflux was similar to inhibition of CCK-induced IP3-dependent Ca2+ efflux.(ABSTRACT TRUNCATED AT 250 WORDS)

Different receptors mediate the action of bombesin-related peptides on gastric smooth muscle cells

Recent studies suggest that different subtypes of receptors may mediate the action of various bombesin-related peptides in different tissues. In the present study the ability of bombesin and its structurally related peptides [litorin, gastrin-releasing peptide (GRP), GRP18-27, neuromedin B, [Leu8]litorin, and bombesin nonapeptide BN(6-14)] to interact with smooth muscle cells isolated from guinea pig stomach was investigated. Each peptide induced a specific contractile response with potencies (D50 in pM) of [Leu8]litorin (0.7) greater than bombesin (1.2) greater than litorin (3) greater than neuromedin B (3.5) = GRP (3.8) = GRP18-27 (3.9) greater than BN(6-14) (70.9). The specific bombesin receptor antagonist psi 13,14-bombesin differed in its potency for inhibiting equipotent concentrations of bombesin, GRP, or neuromedin B, was equipotent for bombesin or GRP (IC50 12.7 and 22.1 nM), and was 11 times less potent for neuromedin B (IC50 234.5 nM), suggesting the presence of subtypes of receptors mediating the action of bombesin-related peptides. To further investigate this possibility, a technique of receptor protection that enables selective preservation of one receptor type was used. GRP or bombesin protected completely the response to GRP or bombesin but abolished the subsequent contractile response to neuromedin B. Neuromedin B, instead, protected only the response to neuromedin B. These results demonstrate that gastric smooth muscle cells possess specific receptors that interact with bombesin-related peptides and that two receptor subtypes mediate the contractile response to these peptides: one subtype is selective for bombesin or GRP, the other for neuromedin B.

Pharmacological characterization of [Leu-13-psi-CH2NH-Leu14]-bombesin as a specific bombesin receptor antagonist on isolated smooth muscle cells

Isolated smooth muscle cells from guinea pig stomach were used to study the pharmacological characteristics of a newly synthetized bombesin analog, [Leu13-psi-CH2NH-Leu14]-bombesin (psi 13,14-BN) to function as antagonist of bombesin-induced contractile response. The antagonism caused by this new analog was compared to that obtained with the substance P analog [D-Arg1,D-Pro2,D-Trp7,9,Leu11]Substance P [( APTTL]SP), which has been used until now to characterize bombesin receptors on smooth muscle cells. psi 13,14-BN resulted to be more potent than [APTTL]SP as antagonist of bombesin action on smooth muscle. Comparing the IC50, psi 13,14-BN (IC50 70 nM) was 8 times more potent than [APTTL]SP (IC50 600 nM). In contrast to [APTTL] SP, the action of psi 13,14-BN was shown to be specific toward bombesin receptors in that it does not interfere with receptors for other agents (i.e., cholecystokinin, acetylcholine or substance P). The antagonism induced by both compounds was competitive inasmuch as the slope of the regression lines obtained by Schild plot analysis were not significantly different from the unity. The apparent affinity for the bombesin receptor was 0.8 nM for psi 13,14-BN and 7.8 nM for [APTTL]SP. These results indicate that psi 13,14-BN acts on isolated gastric smooth muscle cells as a competitive bombesin receptor antagonist, with a higher affinity and specificity than the substance P analog used previously.

Functional gradients in muscle cells isolated from gallbladder, cystic duct, and common bile duct

The existence of a gradient inherent to muscle cells of the biliary tract was examined in muscle cells isolated separately from the fundus of the gallbladder, cystic duct, and common bile duct of the dog. Muscle cells, measured in suspension or as single perfused cells, exhibited a proximal-to-distal gradient expressed by the magnitude of response and the sensitivity to hormonal cholecystokinin octapeptide and neural (acetylcholine and methionine-enkephalin) contractile agonists. Measurements in suspensions showed that cells from the fundus 1) were 7-40 times more sensitive to contractile agonists than cells from the cystic duct and 13-200 times more sensitive than cells from the common bile duct and 2) generated greater maximal contraction. The latter was expressed by the ratio of maximal responses (fundus: cystic duct cells, 1.90 +/- 0.12, P less than 0.001; fundus: common bile duct cells, 1.50 +/- 0.07 P less than 0.001), which was independent of sensitivity to agonists. Similar results were obtained in measurements on single cells with respect to relative sensitivity and to ratio of maximal responses (fundus: cystic duct cells, 1.80 +/- 0.08, P less than 0.001; fundus: common bile duct cells, 1.49 +/- 0.06, P less than 0.001). The ratio of responses to low concentrations of agonists was even higher (three- to fourfold), reflecting both the greater sensitivity and the greater contraction of muscle cells of the fundus. We conclude that a proximal-to-distal biliary gradient exists that is an inherent property of muscle cells from various regions of the biliary tract; the gradient would act to facilitate gallbladder emptying in response to hormonal and neural stimulation.

Identification of separate bombesin and substance P receptors on isolated muscle cells from canine gallbladder

Smooth muscle cells were isolated from the dog gallbladder and used to examine whether bombesin-14 and substance P cause direct contraction and whether this effect is mediated by the same or different receptors. Both peptides caused concentration-dependent contraction that was inhibited by two substance P derivatives, [D-Pro2,D-Trp7,9]SP ([PTT]SP) and [D-Arg1,D-Pro2,D-Trp7,9,Leu11]SP ([APTTL]SP). In nonmuscle cells, these substance P derivatives exhibit preferential antagonism of responses to substance P and bombesin, respectively; accordingly, these properties were used to demonstrate the presence of separate bombesin and substance P receptors. Estimates of the apparent Ki showed that [PTT]SP was 40 times more potent than [APTTL]SP as an antagonist of the response to substance P, whereas [APTTL]SP was 85 times more potent than [PTT]SP as an antagonist of the response to bombesin-14. Estimates of median inhibitory concentration obtained from inhibition curves for the effect of various concentrations of each antagonist on the responses to substance P and bombesin-14 confirmed that [PTT]SP was a preferential antagonist of the response to substance P and [APTTL]SP, a preferential antagonist of the response to bombesin-14. The results demonstrate the presence of separate bombesin and substance P receptors mediating contraction of smooth muscle cells of the dog gallbladder.

Characterization of opioid receptors on isolated canine gallbladder smooth muscle cells

Smooth muscle cells were isolated from the fundus of the canine gallbladder and examined for the presence of opioid receptors. The cells contracted in a concentration-dependent manner in response to three opioid peptides (Met-enkephalin, dynorphin1-13 and Leu-enkephalin), which are known derivatives of opioid precursors present in myenteric neurons of the gut. The order of potency was Met-enkephalin greater than dynorphin1-13 greater than Leu-enkephalin. The contractile response to opioid agonists was selectively inhibited by opioid antagonists (naloxone and Mr2266) but not by muscarinic, CCK/gastrin or tachykinin antagonists. Equivalent responses to the three opioid peptides exhibited differential sensitivity to preferential antagonists of mu (naloxone) and kappa (Mr2266) opioid receptors consistent with the presence of the three main types of opioid receptors (mu, delta and kappa) on canine gallbladder muscle cells.

Gastric acid and pancreatic polypeptide responses to modified sham feeding: indication of an increased basal vagal tone in a subgroup of duodenal ulcer patients

The effect of sham feeding upon gastric acid secretion and pancreatic polypeptide release was investigated in 28 patients with duodenal ulcer in order to evaluate whether high basal vagal activity is the cause of basal acid hypersecretion in patients with duodenal ulcer and basal secretion higher than 30% of their peak acid output. The patients were divided into two groups based on the ratio of basal/pentagastrin stimulated peak acid output (BAO/PAO) was higher or lower than 0.30: group A n = 19 (BAO/PAO less than or equal to 0.30) and group B n = 9 (BAO/PAO greater than 0.30). Gastric acid response to sham feeding (SAO) was significantly higher than basal level in group A (SAO: 11.4 mEq/h (2.5-20.1) vs BAO: 5.2 mEq/h (0.8-22.9), p less than 0.01, median (range)) while in group B the acid secretion did not increase with sham feeding (SAO: 9.6 mEq/h (4.5-13.6) vs BAO: 8.8 mEq/h (6.3-13.8) ns, median (range)). A negative correlation (r= -0.6118226, p less than 0.01) was found between acid increase expressed as basal subtracted sham feeding response (SAO-BAO) and BAO/PAO ratio of the entire group of duodenal ulcer patients (n = 28) suggesting that the greater is basal acid secretory capacity the smaller is acid increase in response to residual vagal activation. Pancreatic polypeptide response to sham feeding was higher in group A than in group B but no correlation (r = 0.20, n = 28) nor individual covariation was found between acid and pancreatic polypeptide secretions during vagal stimulation. sham feeding did not change serum gastrin. It is concluded that an increased vagal stimulation seems to be the cause of basal hypersecretion in a subgroup of patients with duodenal ulcer. The lact of correlation between the pancreatic polypeptide and acid responses to vagal stimulation interferes with the reliability of pancreatic polypeptide as indicator of vagal tone on gastric parietal cells.

Evidence that bombesin releases extragastric gastrin in man

Bombesin-induced gastrin release from extragastric sources has been investigated in two groups of patients without gastric antrum: 11 patients with total gastrectomy and 11 patients with subtotal (Billroth II) gastrectomy. A 30-min bombesin infusion (5 ng . kg-1 . min-1) caused a prompt significant gastrin increase (P less than 0.05) in both groups of patients. The gastrin response to bombesin was significantly (P less than 0.005) lower in patients without antral tissue than in the control group (n = 7). The individual peak gastrin responses, in totally (TG) and subtotally (SG) gastrectomized patients, were significantly over basal levels (TG: peak 100.3 +/- 12 vs. basal 62.8 +/- 9.1, P less than 0.005; SG: peak 96.9 +/- 9.4 vs. basal 72.4 +/- 6.8, P less than 0.001; pg/ml, mean +/- S.E.M.). These data indicate that bombesin acts not only on antral G cells, but on all gastrin cells in the gastrointestinal tract.

Bombesin effects on human GI functions

In this article some of the actions of amphibian skin peptide Bombesin (BBS) on human gastrointestinal and pancreatic functions are reviewed. BBS causes increases of lower esophageal sphincter pressure, delay of gastric emptying, inhibition of mechanical activity of duodenum and jejunum and gallbladder emptying. BBS also releases in man gastrin and stimulates gastric acid secretion. BBS administration induces release of insulin, glucagon and pancreatic polypeptide from human Islet of Langerhans and causes secretion of pancreatic bicarbonates and enzymes in duodenal juice and release of pancreatic enzymes in blood stream.

Effect of bombesin on plasma insulin, pancreatic glucagon, and gut glucagon in man

The effect of bombesin on insulin, pancreatic glucagon, and gut glucagon was investigated in eight healthy volunteers and two pancreatectomized patients. Bombesin, infused iv at the constant rate of 5 ng kg-1 min-1, produced a sharp and statistically significant rise in the plasma insulin concentration. The peak was reached at 5 min (26 +/- 2.17 microU/ml; P less than 0.005 vs. basal values), followed by a prolonged and statistically significant (P less than 0.05) decrease in blood glucose. Pancreatic glucagon rapidly rose to a maximal value of 80.5 +/- 7.6 pmol/liter (P less than 0.005 vs. basal values). In contrast with the prompt increase in insulin and glucagon plasma levels, the peak in gut glucagon concentration (55.8 +/- 4.6 pmol/liter; P less than 0.005 vs. basal values) was reached 30 min after bombesin infusion was discontinued. In the two pancreatectomized patients, bombesin induced an increase in gut glucagon concentrations only. The results presented indicate that bombesin acts directly on the A and B cells of the pancreas, influencing glucose homeostasis; however, more complex mechanisms seem to be involved in gut glucagon secretion.