Effects of minimally invasive surgical and miniscrew-assisted rapid palatal expansion (MISMARPE) on the nasal cavity and upper airway: a comparative cohort study

This study was performed to evaluate the impact on the upper airway and nasal cavity of a new minimally invasive surgical and miniscrew-assisted rapid palatal expansion (MISMARPE) technique for the treatment of adult patients with transverse maxillary deficiency, in comparison to surgically assisted rapid palatal expansion (SARPE). Computed tomography scans of 21 MISMARPE and 16 SARPE patients were obtained preoperatively (T0) and at the end of the activation period (T1) and analysed. Linear and volumetric measurements were performed in the dental, alveolar, nasal cavity, and oropharynx regions. Generalised estimating equations were used to consider the intervention time and surgery type, and their interaction. In both groups, measurements were increased at T1 (P < 0.001), except for oropharynx volume (P > 0.05). A greater expansion in nasal cavity floor and median palatal suture was shown for MISMARPE when compared to SARPE (P < 0.001), with the same degree of expander activation (P = 0.094). A trapezoidal (coronal plane) and 'V' shape (axial plane) expansion pattern, was observed after MISMARPE. Both surgical techniques were effective for maxillary expansion in adults. However, MISMARPE was performed without osteotomy of the pterygomaxillary suture, in an outpatient setting and with local anaesthesia.

Should oral chlorhexidine remain in ventilator-associated pneumonia prevention bundles?

Ventilator-associated pneumonia (VAP) is related with high mortality, duration of mechanical ventilation and costs. Recent studies have questioned the safety and effectiveness of oral chlorhexidine to prevent VAP. We sought to verify whether the adverse effects of this substance outweigh its benefits. We searched several databases and selected studies that investigated the use of oral chlorhexidine and its impact on mortality. No association between oral chlorhexidine and lower VAP rates was found on meta-analyses of double-blind randomized trials, however significant increase in mortality was reported. It is speculated that chlorhexidine can cause damage to several organic sectors and cytotoxicity. Although it still can be beneficial in specific settings, robust evidence to recommend its routine application for all mechanically ventilated patients is lacking; therefore, given the possibility of harm, it would be better to follow the principle of non-maleficence until more studies becomes available.

Antibiotic prophylaxis in orthognathic surgery: an overview of systematic reviews

The purpose of this overview was to assess different antibiotic regimens used in orthognathic surgery and to establish an evidence-based protocol so that beneficial and adverse effects can be determined. A comprehensive literature search for systematic reviews and/or meta-analyses was conducted in MEDLINE (PubMed), EMBASE, and the Cochrane Library until March 2020. Grey literature was investigated in Google Scholar, and a manual search was done of references lists. Two meta-analyses and four systematic reviews met the inclusion criteria. The AMSTAR-2-tool was used to ascertain the potential risk of bias in the included studies, which presented moderate to high methodological quality. Lower infection rates were associated with long-term therapies of penicillin, cefazolin-cephalexin, and amoxicillin-clavulanic-acid, with rates varying from 0% - 3.13%. Higher rates were reported in placebo groups (52.6%) and short-term penicillin therapy (60%). Side effects were reported with cefazolin, clindamycin, and penicillin therapies, including nausea, pain, swelling, headache, vomiting, and skin rash. Evidence suggests that long-term antibiotics can reduce the risk of a surgical site infection (SSI) in orthognathic surgery, but there is uncertainty regarding the effects of one dose of antibiotics preoperatively versus short-term antibiotics. In the same way, intravenous penicillin, cefazolin, clindamycin, and amoxicillin-clavulanic acid kept the infection rates associated with bimaxillary procedures under 3.5%.

Should oral chlorhexidine remain in ventilator-associated pneumonia prevention bundles?

Ventilator-associated pneumonia (VAP) is related with high mortality, duration of mechanical ventilation and costs. Recent studies have questioned the safety and effectiveness of oral chlorhexidine to prevent VAP. We sought to verify whether the adverse effects of this substance outweigh its benefits. We searched several databases and selected studies that investigated the use of oral chlorhexidine and its impact on mortality. No association between oral chlorhexidine and lower VAP rates was found on meta-analyses of double-blind randomized trials, however significant increase in mortality was reported. It is speculated that chlorhexidine can cause damage to several organic sectors and cytotoxicity. Although it still can be beneficial in specific settings, robust evidence to recommend its routine application for all mechanically ventilated patients is lacking; therefore, given the possibility of harm, it would be better to follow the principle of non-maleficence until more studies becomes available.

Stability and surgical complications of tooth-borne and bone-borne appliances in surgical assisted rapid maxillary expansion: a systematic review

The objective of this systematic review was to evaluate the stability and complications of tooth-borne (TB), bone-borne (BB) and hybrid (TB-BB) appliances in surgically assisted rapid maxillary expansion (SARME). Database searches were conducted (PubMed, Embase, Cochrane Library and SciELO), as well as a grey literature search (Google Scholar) and hand searches of reference lists. Forty-six articles were included after study selection (κ=0.854). After eligibility assessment, 16 articles and one article from the grey literature were processed (κ=0.866) and six articles were selected by hand searching, for a total of 23 articles included. Regarding stability, TB appliances showed width relapse rates ranging from 4 to 35% in canines, from 1 to 37% in premolars and from 0.2 to 49.5% in molars. In BB appliances, width relapse rates were 1.7-21% in canines, 1.5% in premolars and 4.6-11.5% in molars. In hybrid appliances, the width relapse rate was 14% in premolars, with a 1.8% overexpansion reported in the molar region. In TB and BB appliances, skeletal relapse rates were similar on the nasal floor (11-53% and 41.6%, respectively) and at the level of the maxilla (18% and 16%, respectively). The most common complications were bone resorption in TB appliances (18.14%) and appliance-related complications in BB appliances (17.9%). The risk of bias was high in 19 studies, medium in three studies and low in one study. The TB and BB appliances used in SARME were considered to have a high long-term stability. BB appliances appeared to have fewer relapses than TB appliances due to a more parallel distribution of forces exerted. However, relapse appears to be highly influenced by postorthodontic treatments, where arch-form coordination is achieved in the consolidation period with the purpose of overexpansion correction, alignment and final vertical adjustments. Further randomised controlled trials with long-term data and large sample sizes are needed to support evidence-based clinical decision-making and to allow meta-analytic studies of stability outcomes regarding the type of anchorage in SARME.

Minimally invasive intraoral proportional condylectomy with a three-dimensionally printed cutting guide

The aim of this study was to describe the steps of a minimally invasive surgical technique used to perform a proportional intraoral condylectomy with a three-dimensionally (3D) printed cutting guide. The technique consists of two steps: virtual surgical planning and intraoral condylectomy. During virtual surgical planning, the mandibular ramus was measured bilaterally, the height of the proportional condylectomy was planned virtually, and a cutting guide was 3D printed. In the intraoral condylectomy, the mandibular condyle was approached intraorally, the 3D printed cutting guide was positioned in the sigmoid notch, and the proportional condylectomy was performed. The protocol reported in this technical note is the sum of knowledge acquired from a series of studies published previously by the authors, who have jointly developed a surgical technique that is both minimally invasive and accurate for the treatment of condylar hyperplasia.

Nasolabial soft tissue effects of segmented and non-segmented Le Fort I osteotomy using a modified alar cinch technique-a cone beam computed tomography evaluation

The aim of this study was to verify soft tissues changes and the effect of a minimally invasive surgical technique in the nasolabial region after segmented and non-segmented Le Fort I osteotomy, using cone beam computed tomography (CBCT) evaluation of three-dimensional (3D) volume surfaces. Two groups were evaluated: group 1, bimaxillary surgery with maxillary segmentation (n=40); group 2, bimaxillary surgery without maxillary segmentation (n=40). In both groups, a specific alar cinching technique was used to control nasal base broadening. CBCT evaluation was performed at three different treatment time points: T0, 1 month before surgery; T1, 1 month after surgery; T2, 1year after surgery. The results showed statistically significant differences in the nasolabial area (P<0.001). For group 1, the mean change in alar base width (Al_inf-Al_inf) was 1.31±1.40mm at T1 and 0.93±1.77mm at T2; for group 2 these values were 1.12±2.01mm at T1 and 0.54±1.54mm at T2. For group 1, the mean changes in inter-alar width (Al-Al) were 1.68±1.46mm at T1 and 1.49±1.33mm at T2; for group 2, they were 2.22±1.93mm at T1 and 1.34±1.79mm at T2. The alar cinch technique proposed here appears to be effective in controlling nasolabial soft tissue widening.

Peripheral perfusion index does not accurately reflect hypoperfusion in healthy dogs undergoing elective ovariohysterectomy

This study evaluated the variability of the peripheral perfusion index (PI) in 22 anaesthetised female dogs undergoing elective ovariohysterectomy and examined the relationship between peripheral PI and heart rate, blood pressure, blood pH, end tidal CO₂ (EtCO₂), O₂ saturation (SpO₂), core-peripheral temperature gradient (ΔTc-p), partial pressure of CO₂ (PCO₂), and concentrations of glucose, cortisol, lactate and bicarbonate (HCO₃^-). Blood pH, lactate and glucose concentrations were determined 15, 30, 45min into the ovariohysterectomy procedure and after extubation. Cortisol concentrations were assessed before anaesthesia and after extubation. Other variables were recorded at every 5min throughout the ovariohysterectomy procedure. Hyperglycaemia was observed in 59% of bitches during surgery, but serum cortisol concentrations remained unchanged. Most measures of perfusion (ΔTc-p, pH, PCO₂, EtCO₂, SpO₂) and heart rate remained unchanged throughout anaesthesia and did not correlate with peripheral PI. Mean arterial pressure increased during the ovariohysterectomy procedure, while peripheral PI decreased, resulting in negative correlations between these variables at 30 and 45min. Lactate concentrations decreased from baseline to the time of measurement post-extubation. Peripheral PI gradually decreased during the ovariohysterectomy procedure, probably reflecting vasoconstriction induced by nociceptive stimuli. Using lactate concentrations as the reference standard for peripheral perfusion, low peripheral PI in healthy bitches undergoing ovariohysterectomy might not represent peripheral hypoperfusion.

Exercise training, creatine supplementation, and bone health in ovariectomized rats

Evidence suggests that creatine may have some beneficial effects on bone. The study aimed to investigate the effects of exercise alone or combined with creatine on bone health in ovariectomized rats. Findings show that exercise, but not creatine, has an important role in improving bone health.

INTRODUCTION

The aim of this study was to investigate the effects of exercise training alone or combined with creatine supplementation on bone health parameters in ovariectomized rats.

METHODS

Wistar rats were randomly allocated into one of five groups: (i) sham-operated, (ii) ovariectomized non-trained placebo-supplemented, (iii) ovariectomized non-trained creatine-supplemented, (iv) ovariectomized exercise-trained placebo-supplemented, and (v) ovariectomized exercise-trained creatine-supplemented. Downhill running training and/or creatine supplementation (300 mg/kg body weight) were administered for 12 weeks. Bone mineral content (BMC), bone mineral density (BMD), and biomechanical and histomorphometric parameters were assessed.

RESULTS

No interaction effects were observed for BMC and BMD at whole body, femur, and lumbar spine (p > 0.05). Importantly, a main effect of training was detected for whole body BMC and BMD (p = 0.003 and p < 0.001, respectively), femoral BMC and BMD (p = 0.005 and p < 0.001, respectively), and lumbar spine BMC and BMD (p < 0.001 and p < 0.001, respectively), suggesting that the trained animals had higher bone mass, irrespective of creatine supplementation. Main effects of training were also observed for maximal load (p < 0.001), stiffness (p < 0.001), and toughness (p = 0.046), indicating beneficial effects of exercise training on bone strength. Neither a main effect of supplementation nor an interaction effect was detected for biomechanical parameters (p > 0.05). No main or interaction effects were observed for any of the histomorphometric parameters evaluated (p > 0.05).

CONCLUSIONS

Exercise training, but not creatine supplementation, attenuated ovariectomy-induced bone loss in this rat model.

Normal esophageal pressure topography metrics for data derived from the Sandhill-Unisensor high-resolution manometry assembly in supine and sitting positions

BACKGROUND

Normal values of the esophageal motor function parameters for high-resolution manometry (HRM-EPT) adopted by the Chicago classification were established using the proprietary system of Given Imaging. It is conceivable that normal values of a system do not apply to data from others. Most studies using HRM were based on supine swallows, whereas deglutition occurs mostly in the upright position. We wished to establish normal values for HRM-EPT parameters obtained with the Sandhill's HRM-EPT system and compare the results in supine and sitting positions.

METHODS

Sixty-nine healthy volunteers, 38 females, median age 27 years, were included in this study. All underwent supine HRM, and 34 of them underwent sitting HRM, with at least 10 single 5-mL swallows for analysis obtained in each position.

KEY RESULTS

The normal range (5-95th percentiles) for the following parameters was calculated: distal contractile integral (DCI), 606-4998 mmHg·s·cm; contractile front velocity (CFV), 2.0-6.5 cm/s; distal latency (DL), 5.1-8.8 s; intrabolus pressure (IBP), 1.9-17.6 mmHg; upper esophageal sphincter (UES) pressure, 45.2-186.9 mmHg; esophagogastric junction (EGJ) length, 1.8-4 cm; EGJ resting pressure, 8.1-61.6 mmHg, and integrated relaxation pressure (IRP) 2.5-23.5 mmHg. Normal values of EGJ resting pressure, IRP, DCI, and IBP but not CFV, DL, and UES resting pressure were significantly lower in the sitting posture.

CONCLUSIONS & INFERENCES

Studies performed with Sandhill's HRM-EPT system should use its own specific normal data. Normal values should be established for different study.

Computer-aided planning in orthognathic surgery-systematic review

The aim of this study was to conduct a systematic review to evaluate the accuracy and benefits of computer-aided planning in orthognathic surgery. The search was performed in PubMed, EMBASE, Cochrane Library, LILACS, and SciELO. The articles identified were assessed independently and in a blinded manner by two authors using selection criteria and eligibility criteria. The database search yielded 375 studies. Following the application of search and eligibility criteria, a final nine studies were included in the systematic review. The level of agreement between the authors in the study selection process was substantial (κ=0.767) and study eligibility was considered excellent (κ=0.863). The accuracy of translation was <1.2mm in the maxilla (vertical) and <1.1mm in the mandible (sagittal), and for rotation was <1.5° in the maxilla (pitch) and <1.8° in the mandible (pitch). Two studies showed a medium potential risk of bias and six studies showed a high potential risk of bias. Computer-aided planning in orthognathic surgery was considered accurate for the studies included in this systematic review. However, the low quality of these studies means that randomized clinical trials are needed to compare computer-aided planning to conventional planning in orthognathic surgery.

Evaluation of tissue response and genotoxicity of poly(L/D-lactic acid) disks implanted in rat calvarium

The aim of the present study was to evaluate local and cytotoxicity systemic tissue reaction in the skull of rats using the implantation of disks of poly (lactic L/D-acid) and evaluate its genotoxicity. 25 males Wistar rats were used, 20 animals underwent surgical procedures and had the discs implanted in the parietal bone, and 5 animals received postoperative medication in the same way, serving as a control group for genotoxicity. The results were subjected to statistical evaluation by analysis of variance (ANOVA). In histological evaluation, between periods of 90 and 120 days in the control group, a new formation at the edges of the defect was noticed. In the experimental group, there was new bone formation at the edges of the defect, migrating below the site occupied by the disk, an absence of inflammatory infiltrate. Regarding the evaluation of genotoxicity, a significant reduction in the frequency of polychromatic erythrocytes in relation to negative control or significant increase in the polychromatic erythrocytes with micronuclei was not detected. So, the material used in this study is biocompatible and well tolerated by the tissues studied, and found to be negative for chromosomal mutagenicity.

The effects of sildenafil on rectal sensitivity and tone in patients with the irritable bowel syndrome

BACKGROUND

Visceral tone supposedly affects gut sensitivity in irritable bowel syndrome (IBS). Sildenafil increases nitric oxide and influences visceral compliance.

AIM

To evaluate the effects of sildenafil tone inhibition on rectal sensitivity.

METHODS

Eight controls and 21 IBS patients (Rome II) were enrolled in a double-blind study, after dosing with placebo or sildenafil (50 mg p.o.). Thresholds for first sensation, first desire to defecate, pain and supraliminar pain were the sensory endpoints, measured with a barostat and 600-mL rectal bag. Pain (100-mm VAS) and depression-anxiety (Hamilton questionnaire) were scored.

RESULTS

Irritable bowel syndrome rectal compliance and sensory-endpoint thresholds were similar to controls. Five IBS patients had pain threshold lower than controls 95% confidence interval (hypersensitive). Depression score was greater in IBS than controls (11.9 ± 1.3 vs. 6.3 ± 2.5, P = 0.036). In IBS, pain intensity was nonsignificantly higher (37.6 ± 5.3 mm vs. 23.4 ± 8.5 mm, P = 0.064) and supraliminar pain intensity was greater (45.6 ± 5.4 mm vs. 25.9 ± 5.1 mm, P = 0.044) than controls. IBS rectal relaxation increased volume (155.4 ± 41.3 mL vs. 118.8 ± 47.7 mL, P = 0.004) and tension (193.1 ± 118.6 mmHg mL(-1) vs. 133.2 ± 98.1 mmHg mL(-1) , P = 0.019) for triggering first desire to defecate but not for other perceptions. Sildenafil increased volume for both first desire to defecate and pain in the hypersensitive IBS patients. Sildenafil increased rectal compliance only in diarrhoea-IBS. Mixed-IBS obtained higher anxiety (12.9 ± 1.3 vs. 5.9 ± 3.1, P < 0.05) and depression scores (13.9 ± 1.9 vs. 6.3 ± 2.5, P < 0.05) and reported more intense supraliminar pain (53.6 ± 9.8 mm vs. 25.9 ± 5.1 mm, P < 0.05) than controls.

CONCLUSIONS

Rectal relaxation following dosing with sildenafil 50 mg increased the first desire to defecate threshold in IBS as a whole, but decreased pain only in the hypersensitive subset. Mixed-IBS presented higher supraliminar pain and anxiety-depression scores.

Role of mitochondria in contraction and pacemaking in the mouse uterus

BACKGROUND AND PURPOSE

Uterine spontaneous contraction and pacemaking are poorly understood. This study investigates the role of the mitochondrial Ca(2+) store in uterine activity.

EXPERIMENTAL APPROACH

We investigated the effects of mitochondrial and sarco-endoplasmic reticulum (SER) inhibitors on contraction, membrane potential (Vm) and cytosolic Ca(2+) concentration ([Ca(2+) ](c) ) in longitudinal smooth muscle of the mouse uterus.

KEY RESULTS

The mitochondrial agents rotenone, carbonylcyanide-3-chlorophenylhydrazone (CCCP), 7-chloro-5-(2-chlorophenyl)-1,5-dihydro-4,1-benzothiazepin-2(3H)-one (CGP37157) and kaempferol decreased the force of contractions. The ATP synthase inhibitor oligomycin had no significant effect. The effects of these agents were compared with those of SER inhibitors cyclopiazonic acid (CPA), 2-amino ethoxyphenylborate (2-APB) and caffeine. All agents, except CPA and oligomycin, decreased contractile force. CPA and CCCP transiently increased contraction frequency, which returned to control levels, whereas rotenone, CGP37157, kaempferol and 2-APB decreased frequency and caffeine had no significant effect. Application of the mitochondrial agents when CPA functionally inhibited stores did not change contraction frequency but, with the exception of kaempferol, decreased force. CCCP caused depolarization and maintained increase in [Ca(2+) ](c) or depolarization/transient hyperpolarization and transient increase in [Ca(2+) ](c) for oestrus and di-oestrus tissues respectively. Rotenone caused hyperpolarization and maintained increase in [Ca(2+) ](c) . CGP37157 and kaempferol caused hyperpolarization but no measurable change in [Ca(2+) ](c) . Application of a range of K(+) channel blockers indicated a role of Ca(2+) -activated K(+) (K(Ca) ) channels in the CCCP- and CGP37157-induced actions.

CONCLUSIONS AND IMPLICATIONS

Mitochondria have a modulatory role on uterine contractions, with mitochondrial inhibition reducing contraction amplitude and pacemaker frequency by changes in Vm, [Ca(2+) ](c) and/or Ca(2+) influx.

Involvement of the Helicobacter pylori plasticity region and cag pathogenicity island genes in the development of gastroduodenal diseases

Infection by Helicobacter pylori is associated with the development of several gastroduodenal diseases, including gastritis, peptic ulcer disease (gastric ulcers and duodenal ulcers), and gastric adenocarcinoma. Although a number of putative virulence factors have been reported for H. pylori, there are conflicting results regarding their association with specific H. pylori-related diseases. In this work, we investigated the presence of virB11 and cagT, located in the left half of the cag pathogenicity island (cagPAI), and the jhp917-jhp918 sequences, components of the dupA gene located in the plasticity zone of H. pylori, in Brazilian isolates of H. pylori. We also examined the association between these genes and H. pylori-related gastritis, peptic ulcer disease, and gastric and duodenal ulcers in an attempt to identify a gene marker for clinical outcomes related to infection by H. pylori. The cagT gene was associated with peptic ulcer disease and gastric ulcers, whereas the virB11 gene was detected in nearly all of the samples. The dupA gene was not associated with duodenal ulcers or any gastroduodenal disease here analyzed. These results suggest that cagT could be a useful prognostic marker for the development of peptic ulcer disease in the state of São Paulo, Brazil. They also indicate that cagT is associated with greater virulence and peptic ulceration, and that this gene is an essential component of the type IV secretion system of H. pylori.

Activation of neural cholecystokinin-1 receptors induces relaxation of the isolated rat duodenum which is reduced by nitric oxide synthase inhibitors

Cholecystokinin (CCK) influences gastrointestinal motility, by acting on central and peripheral receptors. The aim of the present study was to determine whether CCK has any effect on isolated duodenum longitudinal muscle activity and to characterize the mechanisms involved. Isolated segments of the rat proximal duodenum were mounted for the recording of isometric contractions of longitudinal muscle in the presence of atropine and guanethidine. CCK-8S (EC50: 39; 95% CI: 4.1-152 nM) and cerulein (EC50: 58; 95% CI: 18-281 nM) induced a concentration-dependent and tetrodotoxin-sensitive relaxation. Nomeganitro-L-arginine (L-NOARG) reduced CCK-8S- and cerulein-induced relaxation (IC50: 5.2; 95% CI: 2.5-18 microM) in a concentration-dependent manner. The magnitude of 300 nM CCK-8S-induced relaxation was reduced by 100 microM L-NOARG from 73 +/- 5.1 to 19 +/- 3.5% in an L-arginine but not D-arginine preventable manner. The CCK-1 receptor antagonists proglumide, lorglumide and devazepide, but not the CCK-2 receptor antagonist L-365,260, antagonized CCK-8S-induced relaxation in a concentration-dependent manner. These findings suggest that CCK-8S and cerulein activate intrinsic nitrergic nerves acting on CCK-1 receptors in order to cause relaxation of the rat duodenum longitudinal muscle.

A physiological manoeuvre to improve the positivity of the gastro-oesophageal reflux scintigraphic test

One of the best examinations used routinely to detect gastro-oesophageal reflux (GOR) is scintigraphy and attempts are continuously being made to improve the performance of the test. We have tested a new manoeuvre to improve the results. Three hundred and twenty eight patients (190 males and 138 females, aged 1 month to 84 years, average 4.47 years) were studied after a 12 h fast period with 100 MBq of 99Tcm-phytate, 50 ml volume, directly delivered into the stomach in a mixture of orange juice. All patients were strongly suspected of having GOR. Conventional acquisition was done for 20 min, at a rate of one frame every 20 s. In the middle of the examination, small children were put in the upright position and held there for a few seconds or released in a way that allowed movement; adults were asked to stand up and walk a few metres. The test was then continued for the remaining 10 min. The global index of positivity was 64.6% (76 positive cases in the first half of the examination and 134 positive cases only after the manoeuvre). The mean of GOR episodes observed in the positive cases without the manoeuvre was 0.5 per patient, significantly different from the mean of 1.59 noted after the manoeuvre (P<0.01). In 28 cases the manoeuvre increased either the intensity or the frequency of reflux previously detected without it. We believe that this manoeuvre should be performed in all scintigraphic tests aiming to detect GOR. In the present series, the manoeuvre increased the frequency of GOR episodes.

Smooth muscle inclusion bodies in slow transit constipation

Slow transit constipation (STC) is a disorder of intestinal motility of unknown aetiology. Myopathies, including those characterized by the finding of inclusion bodies, have been described in enteric disorders. Amphophilic inclusion bodies have been reported in the muscularis externa of the colon of STC patients. This study formally tested the hypothesis that these represent a primary muscle disorder, specific to STC. In a systematic, blinded, dual observer qualitative and quantitative analysis, colonic and ileal tissue from patients with STC (n=36) were compared with selected control populations: total colonic aganglionosis (n=10), Chagas' disease (n=6), isolated rectal evacuation disorders (n=6), and a control population of a range of ages (n=80). All sections were stained with haematoxylin and eosin and periodic acid Schiff. Further immunostains were used in an attempt to determine inclusion body composition. Round or ovoid (4-22 microm diameter) amphophilic inclusions increased in number in normal subjects with age. Inclusions were more frequent in idiopathic STC than in age-matched controls or rectal evacuation disorders [ileum (33% vs. 9%), ascending (50% vs. 19%, p<0.05), and sigmoid colon (43% vs. 20%)] and were very frequent in the sigmoid (71%) of patients with STC arising after pelvic surgery. The number of inclusions per unit area was significantly higher in patients with STC (p<0.001). Inclusions were found in all Chagas' patients, but not with aganglionosis. It was not possible to determine inclusion body composition, despite the use of a wide range of conventional and immunostains. This study demonstrates that inclusion body myopathy is identifiable in patients with STC and that it may arise secondary to denervation.

Smooth muscle inclusion bodies in slow transit constipation

Slow transit constipation (STC) is a disorder of intestinal motility of unknown aetiology. Myopathies, including those characterized by the finding of inclusion bodies, have been described in enteric disorders. Amphophilic inclusion bodies have been reported in the muscularis externa of the colon of STC patients. This study formally tested the hypothesis that these represent a primary muscle disorder, specific to STC. In a systematic, blinded, dual observer qualitative and quantitative analysis, colonic and ileal tissue from patients with STC (n=36) were compared with selected control populations: total colonic aganglionosis (n=10), Chagas' disease (n=6), isolated rectal evacuation disorders (n=6), and a control population of a range of ages (n=80). All sections were stained with haematoxylin and eosin and periodic acid Schiff. Further immunostains were used in an attempt to determine inclusion body composition. Round or ovoid (4-22 microm diameter) amphophilic inclusions increased in number in normal subjects with age. Inclusions were more frequent in idiopathic STC than in age-matched controls or rectal evacuation disorders [ileum (33% vs. 9%), ascending (50% vs. 19%, p<0.05), and sigmoid colon (43% vs. 20%)] and were very frequent in the sigmoid (71%) of patients with STC arising after pelvic surgery. The number of inclusions per unit area was significantly higher in patients with STC (p<0.001). Inclusions were found in all Chagas' patients, but not with aganglionosis. It was not possible to determine inclusion body composition, despite the use of a wide range of conventional and immunostains. This study demonstrates that inclusion body myopathy is identifiable in patients with STC and that it may arise secondary to denervation.

Smooth muscle inclusion bodies in slow transit constipation

Slow transit constipation (STC) is a disorder of intestinal motility of unknown aetiology. Myopathies, including those characterized by the finding of inclusion bodies, have been described in enteric disorders. Amphophilic inclusion bodies have been reported in the muscularis externa of the colon of STC patients. This study formally tested the hypothesis that these represent a primary muscle disorder, specific to STC. In a systematic, blinded, dual observer qualitative and quantitative analysis, colonic and ileal tissue from patients with STC (n=36) were compared with selected control populations: total colonic aganglionosis (n=10), Chagas' disease (n=6), isolated rectal evacuation disorders (n=6), and a control population of a range of ages (n=80). All sections were stained with haematoxylin and eosin and periodic acid Schiff. Further immunostains were used in an attempt to determine inclusion body composition. Round or ovoid (4-22 microm diameter) amphophilic inclusions increased in number in normal subjects with age. Inclusions were more frequent in idiopathic STC than in age-matched controls or rectal evacuation disorders [ileum (33% vs. 9%), ascending (50% vs. 19%, p<0.05), and sigmoid colon (43% vs. 20%)] and were very frequent in the sigmoid (71%) of patients with STC arising after pelvic surgery. The number of inclusions per unit area was significantly higher in patients with STC (p<0.001). Inclusions were found in all Chagas' patients, but not with aganglionosis. It was not possible to determine inclusion body composition, despite the use of a wide range of conventional and immunostains. This study demonstrates that inclusion body myopathy is identifiable in patients with STC and that it may arise secondary to denervation.

Gastrointestinal manifestations of Chagas' disease

Chagas' disease is an infectious disease that affects millions of people in Latin America and is increasingly seen outside endemic areas. A substantial number of patients develop gastrointestinal disorders secondary to lesions of the enteric nervous system. The purpose of this article is to review the current knowledge about gastrointestinal manifestations of Chagas' disease, including disorders other than the well-known gross dilations of esophagus and colon.

Nonadrenergic-noncholinergic relaxations of isolated circular muscle from South American opossum esophagogastric junction: is nitric oxide the inhibitory mediator?

Nonadrenergic-noncholinergic (NANC) inhibitory nerves are responsible for most of the nerve induced relaxations of gastrointestinal muscle. It has recently been proposed that NANC nerves may release nitric oxide (NO) or a related compound derived from L-arginine. We have recently shown that the South American (SA) opossum is another suitable model to elucidate the mechanism involved in these NANC relaxations. In the present study the effect of NO synthase inhibitors as well as NO inactivators on the NANC-nerve induced relaxations of the circular muscle of the esophagogastric junction (EGJ) of the SA opossum was investigated. It was observed that the NO synthase inhibitors, L-NOARG and L-NAME, caused a concentration-dependent reduction of NANC-nerve induced relaxations which was reversed by L- but not D-arginine. The NO-donors sodium nitroprusside and hydroxilamine as well as NO caused concentration-dependent relaxations of the EGJ circular muscle. In the myenteric plexus of this region, NADPH-diaphorase positive neurons and nerve fibers were observed while in the circular muscle layer only numerous positive fibers were found. The NO inactivators, hydroquinone, pyrogallol and carboxy-PTIO, reduced NO-induced relaxations but failed to affect NANC nerve- and sodium nitroprusside-induced relaxations. Taken together, these findings indicate that NANC nerve induced relaxation of the SA opossum EGJ circular muscle is dependent on neural NO synthase activity and suggest that the neurotransmitter being released is a superoxide resistant molecule, which is unlikely to be the NO radical, or that the activity of NO synthase is required for the release of the actual neurotransmitter rather than for synthesizing the neuromediator.

[Fetal hydronephrosis: postnatal management and follow up]

OBJECTIVE

Fetal hydronephrosis is being detected with increasing frequency and probably this observation will increase as the quality of ultrasound equipment improves. This study evaluated etiology and postnatal clinical outcomes of prenatally detected hydronephrosis.

METHODS

In a period of 13 years 148 infants were referred with fetal hydronephrosis. The initial evaluation, after prophylaxis, included ultrasound and voiding cystography. Sequential evaluation was determined by initial findings.

RESULTS

Postnatal predominant diagnosis were pelviureteric junction obstruction (24%) and hydronephrosis without obstruction (18%). Follow up median was 38.7 months. Renal function deteriorated in 13 (8.8%) children and 11 (7.4%) died during follow up. Bad prognosis was associated with urethral obstruction.

CONCLUSIONS

Fetal hydronephrosis is a clue of urinary tract anomalies. Urinary tract infections and delay in postnatal diagnosis must be prevented in children with this uropathy.

[The excretion of H2 in the air expired by patients with pancreatic diseases]

In order to attain a diagnostic procedure able to detect intestinal malabsorption we studied the effect of rice flour ingestion (30 g) on H2 levels in the expired air of asymptomatic volunteers (n = 12) and in pancreas failure patients, either with (n = 15) or without steatorrhea (n = 13). The excretion of H2 in the expired air from pancreatopathic patients with steatorrhea were well above than those obtained from patients without steatorrhea (P < 0.05). Our results suggest that H2 breath test could be utilized to recognize intestinal malabsorption in individuals with exocrine pancreas disease.

The spectrum of esophageal motor disorders in Chagas' disease

OBJECTIVE

To determine the patterns of esophageal motility found in patients with Chagas' disease.

METHODS

Clinical, manometric, and scintigraphic data were obtained from 43 subjects with positive serological tests for Chagas' disease and nondilated esophagus and 10 patients with Chagasic megaesophagus.

RESULTS

Twenty (46.5%) of the seropositive subjects with nondilated esophagus were asymptomatic, and 23 (53.5%) had dysphagia, but only 12 (27.9%) had persistent dysphagia, a feature typical of Chagasic megaesophagus; only two (4.6%) had chest pain. Manometric findings within the seropositive group were: normal motility in 16 subjects, peristaltic multipeaked contractions in three, aperistalsis of the esophagus with relaxing lower esophageal sphincter in nine, and aperistalsis with nonrelaxing lower esophageal sphincter in 15 subjects. All of 10 megaesophagus patients had aperistalsis of the esophagus plus nonrelaxing lower esophageal sphincter. Scintigraphy was as sensitive as manometry in detecting esophageal dysmotility, but the erect scintigraphy was abnormal in subjects with complete aperistalsis only.

CONCLUSION

In Chagas' disease, megaesophagus appears to be a disorder at the most severe end of a spectrum encompassing classical achalasia and its milder variants. Other esophageal motility disorders are rare, but normal esophageal function is common.

Causes of diarrhoea in patients with hypogammaglobulinaemia

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[Small bowel bacterial overgrowth syndrome in chagasic megajejunum: report of 2 cases]

We report two cases of Chagas' disease with megacolon who presented with chronic diarrhea. One of the patients also had evidence of malabsorption, such as steatorrhea and hypocalcemia. Barium meal follow-through showed remarkable dilation of the jejunum in both cases and, in one of them, an associated megaduodenum. Manometric studies of gastrointestinal motility showed abnormally slow propagation of the interdigestive migrating motor complex, which was also excessively prolonged. Cultivation of jejunal aspirates revealed strict anaerobic bacterial growth in both cases. Oral antibiotic therapy led to substantial improvement in symptoms. The two cases herein reported indicate that clinical manifestations of small bowel bacterial overgrowth, possibly caused by motor disturbances associated with megajejunum, may occasionally include the clinical picture of gastrointestinal involvement in Chagas' disease.

Comparison of the effects of sublingual isosorbide dinitrate and cardiomyotomy on esophageal emptying in patients with chagasic megaesophagus

The effects of surgical cardiomyotomy and isosorbide dinitrate on esophageal emptying were compared in 18 patients with symptomatic chagasic megaesophagus. The esophageal emptying of a radiolabelled test meal was assessed three times in each patient by a scintigraphic technique, twice before and once 10-14 days after cardiomyotomy. Isosorbide dinitrate, 5 mg by the sublingual route 5 min before the meal, preceded one of the preoperative studies. Esophageal retention at the completion of the meal was significantly less (P < 0.01) after both isosorbide dinitrate and cardiomyotomy than after the preoperative study not preceded by any treatment. This difference persisted up to 10 minutes after the meal. The values measured in the isosorbide dinitrate-preceded study and after cardiomyotomy were not different (P > 0.10) even though esophageal retention at the completion of the meal was slightly less after cardiomyotomy than after isosorbide dinitrate. These results show that isosorbide dinitrate and cardiomyotomy cause similar enhancement of esophageal emptying in chagasic megaesophagus.

Abnormalities of the interdigestive migrating motor complex in a patient with carcinoid syndrome

Intraluminal pressures of the gastric antrum, duodenum and jejunum were recorded for 206 min after a 12 h fast in a patient with carcinoid syndrome due to neoplasia of enterochromaffin cells of the ileum and with hepatic metastases. The most conspicuous alteration was a tachyrrhythmia of 16 waves/min predominating in the activity fronts of both duodenum and jejunum. Periods of 11-12 waves/min frequency appeared irregularly and the simultaneous occurrence of frequencies of 11 waves/min and 16 waves/min was also recorded. The gastric antrum was fully quiescent throughout the study. The alterations observed are presumed to be produced by substances secreted by the carcinoid tumor.

Clinical characteristics of acute myocardial infarction in patients with Chagas' disease

From 1981 to 1988, 404 patients at our institution were found to have acute myocardial infarction. Of them, 18 (4%) had a positive fixation test for Chagas' disease. Patient age ranged from 41 to 80 years (median = 59). Eleven patients were males. Eighteen nonchagasic patients were matched by 2 year age intervals and sex with each chagasic patient. Before acute myocardial infarction, there were no differences between chagasic and nonchagasic patients with regard to the proportion of stable angina, unstable angina and coronary risk factors. Atypical chest pain occurred in 8 of 15 (53%) chagasic patients for whom this information was found in the medical records and in 1 of 18 (5%) nonchagasic patients (p = 0.003); dyspnea and palpitations occurred in 6 of 15 (40%) chagasic and 1 of 17 (5%) nonchagasic patients (p = 0.025). There were no differences between chagasic and nonchagasic patients with respect to both clinical characteristics and cardiac complications of acute myocardial infarction. Nonetheless, 4 of 11 (36%) chagasic patients for whom this information was listed in the medical records but none of 16 nonchagasic patients had normal coronary arteries (p = 0.019). Thus, chagasic patients who develop acute myocardial infarction have some peculiarities both in the clinical profile before the acute event and in the anatomy of the coronary arteries.

An AC biosusceptometer to study gastric emptying

A simple AC susceptometer was developed to study the gastric emptying when test meals labeled with 10% of a harmless magnetic tracer were ingested. The instrument allows the determination of T 1/2 of the stomach emptying with good precision compared to measurements with gamma camera and 99m Tc in the test meal.

[Tissue levels of 6-ketoprostaglandin Fl alpha and integrity of gastric mucosa in patients with Chagas disease]

An increased prevalence of chronic gastritis has been reported in patients with chronic Chagas' disease (American trypanosomiasis), which is regarded to be model of intrinsic denervation of the gastrointestinal tract. In order to investigate whether this condition is associated with a reduction of prostaglandin levels in gastric mucosa, we studied 14 Chagas' disease patients with megaesophagus and/or megacolon and compared them with 10 control subjects. All patients and controls underwent an upper gastrointestinal tract endoscopy where biopsies were collected from the antrum for histology and for 6-keto-PGF 1 alpha radioimmunoassay. In the Chagas' disease group, the proportion of patients with either moderate or severe gastritis (7/14) was significantly higher (p < 0.01) than in the control group (0/10). Values for antral 6-keto-PGF 1 alpha in Chagas' disease patients (median: 80.75 ng/g; range 36.5-245.6 ng/g) were slightly lower than those obtained in controls (median: 116.2 ng/g; range: 13.1-269 ng/g), but the difference was not statistically significant (p > 0.10). These results confirm previous observations suggestive of an increased prevalence of chronic gastritis in Chagas' disease, but do not support the view that chronic destruction of the intramural neurons of the gut, which is known to occur in this condition, is associated with a reduction of prostaglandin levels in gastric antral mucosa.

Clinical profile of patients with Chagas' disease before and during sustained ventricular tachycardia

Sustained ventricular tachycardia was diagnosed in 15 patients undergoing ordinary activity with Chagas' disease seen at our Institute from 1978 to 1989. Palpitations were observed in 11 (66%) of the patients, dyspnea in 7 (46%), atypical chest pain in 5 (33%) and syncope in 2 (13%). Cardiac arrhythmia was detected in 4 (26%) on physical examination. The resting electrocardiogram showed premature ventricular contractions in 13 (86%) patients, ST-T changes in 12 (80%), left axis deviation in 9 (60%) and right bundle branch block in 4 (26%). Chest X-rays showed mild cardiomegaly in 8 (53%) and moderate cardiomegaly in 3 (20%) patients. Mild left ventricular dysfunction was detected echocardiographically in 1 (10%), moderate in 3 (30%) and severe in 1 (10%) of the 10 patients studied. During sustained ventricular tachycardia, dyspnea was found in 7 of 15 (46%) patients, palpitations in 6 (40%), atypical chest pain in 6 (40%), syncope in 1 (6%), systemic arterial hypotension in 3 (20%) and cardiogenic shock in 2 (13%). The electrocardiographic findings were as follows: mean heart rate was 201 bpm; mean QRS lengthening was 0.16 sec; right bundle branch block plus right axis deviation was seen in 5 of 15 (33%) patients; right bundle branch block plus left axis deviation in 4 (26%); and a positive concordance of all precordial leads in 5 (33%) patients. Based on these findings, we conclude that the majority of patients with Chagas' disease who develop sustained ventricular tachycardia do not have severe myocardial disease, show an uncommon electrocardiographic pattern of this arrhythmia, and most importantly, have a benign clinical course.

[The effect of isosorbide dinitrate on esophageal emptying in chagasic megaesophagus]

The effect of 5 mg of sublingual dinitrate isosorbide (DNI) on the esophageal emptying of a semi-solid test meal labeled with 99mTc-sulfur colloid was studied by a scintigraphic technique in 18 chagasic patients with megaesophagus. DNI significantly reduced the esophageal retention measured at 0, 5, 10, 15, and 20 minutes after the end of the test meal ingestion. Five minutes after the meal not preceded by DNI the esophageal retention was always higher than 10% whilst 5 minutes after the meal preceded by DNI the retention was lower than 10% in 10 patients. These results indicate that DNI may be useful to reduce esophageal retention in chagasic megaesophagus.

[Semiology and physiopathology of the motor activity of the esophagus]

This paper reviews the current concepts on the esophageal motility disorders, with emphasis on the diagnostic aspects.

Immediate effects of the endoscopic sphincterotomy on the motility of the sphincter of Oddi

An endoscopic manometric technique was used to determine the CBD-duodenum junction pressure profile before and immediately after endoscopic sphincterotomy in 13 patients with common bile duct stones. Premedication (meperidine, atropine, and diazepam) was given to all patients and endoscopic retrograde cholangiopancreatography was performed before endoscopic sphincterotomy. In the patients with intact papilla the features of the sphincter of Oddi motility were similar to those previously described for patients not given premedication or submitted to cholangiography before endoscopic sphincterotomy. Endoscopic sphincterotomy which was successful for immediate stone removal in 9 of 13 patients caused an immediate reduction of sphincter of Oddi motility in all patients, but abolished it in only 2 of them. The present results show that successful common bile duct stone extraction by means of endoscopic sphincterotomy can be accomplished without total abolition of sphincter of Oddi motility.

[Effect of isosorbide dinitrate on the lower esophageal sphincter pressure in patients with Chagas' disease]

The effect of 5 mg of sublingual isosorbide dinitrate on the lower esophageal sphincter pressure of 28 chagasic patients with esophageal involvement, was studied by continuous perfusion manometry. The pressure was measured at 5 minute intervals for 60 minutes after drug administration. Isosorbide dinitrate reduced sphincter pressure from 5 to 60 minutes (p less than 0.01). Only two patients hadn't sphincter pressure reduced lower than 50% of initial value at 20 minutes after drug administration. These results indicate that isosorbide dinitrate may be useful to reduce lower esophageal sphincter pressure in chagasic megaesophagus.

Dysphagia lusoria and segmental aperistalsis in the upper third of the esophagus

An aperistaltic zone located in the upper third of the esophagus was present in a young woman with dysphagia, who had undergone surgical treatment for dysphagia lusoria 3 months before. The segmental absence of contraction in the upper third of the esophagus was the most probable cause for the persistence of dysphagia, and could have resulted from damage related to compression or to surgical intervention in the area.

The effect of a segmental gastrectomy with proximal gastric vagotomy on gastric secretion and gastric emptying

Gastric acid secretory responses to graded doses of pentagastrin were measured in duodenal ulcer patients before and after either proximal gastric vagotomy (17 patients) or proximal gastric vagotomy associated with a segmental gastrectomy (11 patients). Calculated maximal output of acid and responsiveness of the acid-secreting cells to pentagastrin were reduced by both operations; after surgery, maximal acid output was lower in the proximal gastric vagotomy plus segmental gastrectomy group than in the proximal gastric vagotomy group. Gastric emptying of a liquid meal was assessed before and after either proximal vagotomy (13 patients) or proximal gastric vagotomy plus segmental gastrectomy (9 patients). The early phase of emptying was equally accelerated by both operations, and at later stages the emptying was only slightly, but not significantly, faster following proximal gastric vagotomy associated with segmental gastrectomy.

Segmental absence of contraction in the upper third of the esophagus

In a manometric study of esophageal motility, segmental absence of contraction was encountered in the upper third of the esophagus in five patients, although only two of them had complained about dysphagia. If the manometric patterns were identical in the patients with and without dysphagia, it is difficult to explain this symptom in all the cases.

Gastric emptying of lactose and glucose-galactose in patients with low intestinal lactase activity

To test the hypothesis that in subjects with low intestinal lactase activity (LLA) lactose solutions leaves the stomach at an abnormally fast rate, we have measured the gastric emptying rate of solutions of lactose and glucose-galactose in patients with LLA (n = 9) and in control subjects with high intestinal lactase levels (n = 7) as proved by the assay of disaccharidases in specimens of intestinal mucosa. The volume of the test meals was 300 ml. Lactose solutions contain 50 g of disaccharide and glucose-galactose solutions contain 25 g of each monosaccharide. The volumes remaining in the stomach at different times after the intragastric instillation of the test meals were estimated by the double sampling test meal. In the control group, minor differences between lactose and glucose-galactose gastric emptying rates was found. By contrast, in LLA patients, the lactose meal left the stomach at a significantly faster rate than the glucose-galactose test meal. These findings support previous evidence obtained in patients with putatively low intestinal lactase activity and are consistent with the view that duodenal osmoreceptors, whose excitation results in inhibition of gastric emptying, lie deeper than the disaccharidases in intestinal mucosa. Thus, incomplete hydrolysis of lactose results in a faster than normal gastric emptying rate of the sugar and this may contribute to the symptoms found in LLA patients after milk ingestion.