Phenotype severity in the bladder exstrophy-epispadias complex: analysis of genetic and nongenetic contributing factors in 441 families from North America and Europe

OBJECTIVE

To identify genetic and nongenetic risk factors that contribute to the severity of the bladder exstrophy-epispadias complex (BEEC).

STUDY DESIGN

Patients with BEEC from North America (n = 167) and Europe (n = 274) were included. The following data were collected: associated anomalies, parental age at conception, mode of conception, periconceptional folic acid supplementation, maternal risk factors during pregnancy, and environmental risk factors. The patients were divided into 3 subgroups according to phenotype severity: (i) mild, epispadias (n = 43); (ii) intermediate, classic bladder exstrophy (n = 366); and (iii) severe, cloacal exstrophy (n = 31). These subgroups then were compared with identify factors that contribute to phenotype severity.

RESULTS

Males were overrepresented in all subgroups. A relatively high prevalence of cleft lip, with or without cleft palate, was observed. Maternal smoking and medical radiation during the first trimester were associated with the severe cloacal exstrophy phenotype. Compliance with periconceptional folic acid supplementation was associated with the mildest phenotype (epispadias).

CONCLUSIONS

Periconceptional folic acid supplementation appears to prevent the development of the severe phenotype of BEEC.

De novo partial trisomy 18p and partial monosomy 18q in a patient with anorectal malformation

Anorectal malformations (ARM) encompass a broad clinical spectrum which ranges from mild anal stenosis to severe anorectal anomalies such as complex cloacal malformations. The overall incidence of ARM is around 1 in every 2,500 live births. Although causative genes for a few syndromic forms have been identified, the molecular genetic background of most ARM remains unknown. The present report describes a patient with a de novo 13.2-Mb deletion of chromosome 18q22.3-qter and a 2.2-Mb de novo duplication of chromosomal region 18pter-p11.32 located at the telomeric end of chromosome 18q. The patient presented with ARM and the typical features of 18q- syndrome (De-Grouchy syndrome). The combination of a partial duplication of the short arm and a partial deletion of the long arm of chromosome 18 has been described in 16 previous cases. However, this is the first report of an association between this complex chromosomal rearrangement and ARM.

Autosomal-dominant non-syndromic anal atresia: sequencing of candidate genes, array-based molecular karyotyping, and review of the literature

INTRODUCTION

Anorectal malformations (ARM) range from mild anal to severe anorectal anomalies. Approximately 50% are estimated to be non-syndromic with multiple familial cases reported that suggest underlying genetic factors. These, however, still await identification.

MATERIALS AND METHODS

We report a familial case of non-syndromic ARM with a mother and her two children being affected. Mother and daughter had mild ARM that had only been diagnosed after the index patient was born with a more severe form and ultrashort Hirschsprung's disease. To reveal the genetic cause in our family genome-wide array analysis was carried out to ascertain microaberrations characterized by loss or gain of genomic material. In addition, sequence analysis of four major Hirschsprung's disease genes (RET, EDNRB, EDN3, and GDNF) and the HLXB9 gene was performed to identify a mutation common to all three family members; however, these analyses did not reveal any causal genetic alteration. To demonstrate the frequency of familial non-syndromic cases, we performed a literature search revealing 59 families with at least two affected members. Sufficient description of ARM phenotype and affection status of relatives to surely classify them as familial non-syndromic forms was given for 22 families.

CONCLUSION

The present family suggests that mild ARM may be overlooked in patients with non-specific clinical symptoms and that the incidence of ARM may thus be higher than previously estimated. With the new possibilities of whole exome sequencing, even small families hold the possibility to identify causal defects.

Osteoarthritis - a role for weight management in rheumatology practice: an update

Osteoarthritis (OA) and obesity are related diseases, which occur in a large proportion of the population. Epidemiological evidence show that weight is of great importance for the development of OA in the knee, and to some extent also in hip and finger joints. Once acquired, the OA contributes to further weight problems by decreasing the daily activity level. Weight loss will be beneficial for the knee and experimental data point at a highly significant effect on knee function and recent results even point at a positive effect on the cartilage of the knee joint. Recommending patients with a combination of knee OA and obesity to lose at least 5% body weight, and aim for 10% is predicted to correspond to 26% improvement in physical function. A programme for this weight loss has been tested with good results applying an initial formula diet with maintenance therapy in groups during follow-up.

Evidence for linkage of the bladder exstrophy-epispadias complex on chromosome 4q31.21-22 and 19q13.31-41 from a consanguineous Iranian family

BACKGROUND

The bladder exstrophy-epispadias complex (BEEC) is a spectrum of anomalies involving the abdominal wall, pelvis, urinary tract, genitalia, and, occasionally, the spine and anus. Although BEEC typically occurs sporadically, families with two or more affected members have been reported. The present authors previously conducted a genome-wide linkage analysis in two multiply affected (multiplex) families (one of German and one of Spanish origin), which revealed several chromosomal regions compatible with linkage. In the present study, genome-wide linkage analysis was performed in a recently reported consanguineous Iranian multiplex family with an affected sibling pair: a female with epispadias and a male with classic exstrophy of the bladder.

METHODS

The Affymetrix 250K Sty chip (238,304 single nucleotide polymorphisms) was used to genotype the parents and four children, including the two affected siblings. Parametric and nonparametric linkage analyses were performed.

RESULTS

Parametric linkage analysis under a recessive model with complete penetrance identified seven loci with LOD scores >1.6 (1p33, 4q31.21-22, 9q22.33, 12q13.13-2, 13q12.12-13, 18q23, and 19q13.31-41). These results were supported by nonparametric linkage analysis. Haplotype analysis showed that the affected individuals were homozygous identical by descent for all seven regions. Two of these regions overlapped with regions observed previously in the Spanish family -one on chromosome 4q31.21-22, and the other on chromosome 19q13.31-41.

CONCLUSION

These results suggest that chromosomal regions 4q31.21-22 and 19q13.31-41 are likely to harbor genes for an autosomal recessive form of BEEC.

Research perspectives in the etiology of congenital anorectal malformations using data of the International Consortium on Anorectal Malformations: evidence for risk factors across different populations

PURPOSE

The recently established International Consortium on Anorectal Malformations aims to identify genetic and environmental risk factors in the etiology of syndromic and nonsyndromic anorectal malformations (ARM) by promoting collaboration through data sharing and combined research activities.

METHODS

The consortium attempts to recruit at least 1,000 ARM cases. DNA samples are collected from case-parent triads to identify genetic factors involved in ARM. Several genetic techniques will be applied, including SNP arrays, gene and whole exome sequencing, and a genome-wide association study. Questionnaires inquiring about circumstances before and during pregnancy will be used to obtain environmental risk factor data.

RESULTS

Currently, 701 ARM cases have been recruited throughout Europe. Clinical data are available from all cases, and DNA samples and questionnaire data mainly from the Dutch and German cases. Preliminary analyses on environmental risk factors in the Dutch and German cohort found associations between ARM and family history of ARM, fever during first trimester of pregnancy and maternal job exposure to cleaning agents and solvents.

CONCLUSION

First results show that both genetic and environmental factors may contribute to the multifactorial etiology of ARM. The International Consortium on Anorectal Malformations will provide possibilities to study and detect important genes and environmental risk factors for ARM, ultimately resulting in better genetic counseling, improved therapies, and primary prevention.

Embryonic expression of the cysteine rich protein 61 (CYR61) gene: A candidate for the development of human epispadias

BACKGROUND

Isolated epispadias is the mildest phenotype of the exstrophy-epispadias complex, a urogenital birth defect of variable severity. The androgen receptor antagonist flutamide (FLU) is known to cause malformations in the rat genital and reproductive tract, and single-dose prenatal FLU exposure can induce epispadias in rat offspring. The Cyr61 gene exhibited the highest response to FLU in rat fetal testis, and we suggested it a promising candidate gene for epispadias in humans, because its protein product promotes proliferation, migration, and adhesion of endothelial cells and fibroblasts.

METHODS

We used whole mount in situ analysis in mice to investigate ventrocaudal expression of the Cyr61 transcript at gestational days 9.5 to 11.5, which is the equivalent of human gestational weeks 4 to 6 (postulated time of epispadias organogenesis in humans). We also performed mutational analysis of the CYR61 gene in 11 patients with isolated epispadias and in additional eight patients with the related classic bladder exstrophy phenotype.

RESULTS

Expression of Cyr61 was detected in endothelial cells of vessels surrounding the cloaca and the umbilical cord on gestational days 10 and 11.5. The mutation screening, however, revealed no alterations in the coding region of human CYR61.

CONCLUSIONS

The spatiotemporal expression pattern observed suggests a role for Cyr61 in the development of the external genitalia. Our mutation screening study, however, could not confirm that mutations affecting the CYR61 gene are a frequent cause of epispadias or classic bladder exstrophy, although rare mutations might be detectable in larger patient samples.

Möglichkeiten und Grenzen der transkraniellen Farbduplexsonographie bei der Darstellung intrakranieller arteriovenöser Malformationen

PURPOSE

Using transcranial color coded duplex sonography (TCCS) it is possible to visualize intracranial arteriovenous malformations (AVMs). The purpose of this study is to describe their typical ultrasonographic features and to define sensitivity for diagnosis with regard to the localization of an AVM.

MATERIALS AND METHODS

Over a period of six years we prospectively examined 54 intracranial AVMs confirmed by angiography. Using TCCS the vessels of the circle of Willis were identified by location, course and direction of flow on color flow images. The examination was performed during the first three years of the study using the Acuson 128 XP 10 system, equipped with a sector transducer with a 2.0/2.5 - MHz imaging frequency for the transcranial examination, and with a 7.0 MHz linear transducer fot the extracranial examination. During the second three years of the study, transcranial examination was performed with an Acuson Seqouia 512 ultrasound system equipped with a 2 - 4 MHz phased array transducer.

RESULTS

In accordance with digital subtraction angiography, the intracranial AVMs could be visualized in 42 cases (77.8 %). The major feeding vessels of the AVMs could be easily identified due to typical hemodynamic parameters showing increased systolic and diastolic flow velocities and decreased pulsatility index. We failed to visualize AVMs localized near the cortex, i. e. in the parietal, frontal, occipital and cerebellar regions of the brain. In contrast, 88.9 % of AVMs localized in the basal regions were very easy to image. Additionally, TCCS was useful for postoperative or postinterventional follow-up, although only a limited number of patients could be examined by TCCS in the post-treatment period.

CONCLUSION

TCCS is a noninvasive method for the diagnosis and possibly valuable in the long-term follow-up of intracranial AVMs. However, further research is needed to establish TCCS as an imaging modality in the follow-up after treatment of AVMs. The method can be regarded as a useful supplement to the palette of established, noninvasive diagnostic techniques such as MRI and MRA. However, since TCCS cannot rule out an AVM, angiography is still the method of choice for the definitive diagnosis.

Evaluation of cerebral perfusion deficit in stroke patients using new transcranial contrast imaging CPS technology--preliminary results

BACKGROUND AND PURPOSE

Contrast-enhanced transcranial duplex sonography can be used to examine cerebral perfusion. This technique, however, is still faced with methodological problems. The aim of the present study is to evaluate cerebral perfusion deficit after administration of the contrast agent SonoVue in acute stroke patients using new contrast imaging software.

METHODS

Ten subjects (6 male stroke patients and 4 healthy volunteers), were examined using transcranial duplex sonography (Acuson Sequoia 512 Ultrasound System) after a bolus injection of the contrast agent SonoVue. The transcranial examination was performed using transient response harmonic grey scale imaging with refill kinetics. The Sequoia ultrasonographic system was equipped with a new contrast harmonic imaging software "Cadence contrast pulse sequencing technology" (CPS). Triggered images with the mechanical index (MI) at 1.1 as well as continuous registration with MI at 0.28 were used for the evaluation of time intensity curves in several regions of interest. The sonographically imaged hypoperfused areas were compared with findings from MR imaging.

RESULTS

In all healthy volunteers, the contrast-enhanced signal could be recognized well in the ipsi- and also in the contralateral hemisphere up to the skull crown. In stroke patients, the perfusion deficit in the area of the MCA could be detected ipsilaterally in all subjects using triggered registration. Additionally, the area of MCA infarction could also be visualized in two patients using contralateral insonation. The low MI continuous imaging was successful in three patients. For all patients, the ischaemic region corresponded well in shape and size with the findings from MR imaging.

CONCLUSIONS

CPS enhances the possibility of perfusion-imaging in cerebral microcirculation and of perfusion-deficit-imaging in patients with cerebral ischaemia. Further studies with a larger number of patients should be carried out to improve this method.

Transcranial contrast imaging of cerebral perfusion in stroke patients following decompressive craniectomy

AIM

Contrast-enhanced transcranial triggered B-mode technology can be used to examine cerebral perfusion. However, this technique is still faced with methodological problems, especially the difficulty of overcoming the temporal bone window. The aim of the present study is to evaluate a deficit in cerebral perfusion after administration of the contrast agent SonoVue (TM) in acute stroke patients following decompressive craniectomy.

METHODS

Ten stroke patients (aged 39 to 59 years, mean age 57 years), in whom a decompressive craniectomy due to a malignant space-occupying infarction or intracerebral haemorrhage was performed, were examined with transcranial duplex sonography after application of the contrast agent SonoVue (TM). The transcranial examination was performed using transient response harmonic grey scale imaging with bolus kinetics based on a contrast harmonic imaging software with single-pulse transmission technology. The mechanical index was set at 1.0 to 1.1. Triggered images with pulsing intervals of 1000 ms were used for the evaluation of time intensity curves in several regions of interest. The sonographically imaged areas of hypoperfusion were compared with CT or MRI findings.

RESULTS

After injection of the contrast agent, the perfusion deficit could be detected ipsilaterally according to the affected vascular territory in the area of the MCA in 5 patients, in the area of ACA and MCA in 2 patients, in the area of the MCA, ACA and PCA in one patient and in the area of intracranial haemorrhage in 2 patients. The calculated average peak images corresponded precisely with the superimposed CT or MRI images in shape and size in all patients. Additionally, it was possible to observe several interesting contrast-induced phenomena in the cerebral parenchyma, as well as specific transit-time curve characteristics in the perfusion deficit area.

CONCLUSIONS

Using contrast-enhanced transcranial duplex sonography with transient response harmonic imaging, it is possible to depict the perfusion deficit in cerebral microcirculation in patients following decompressive craniectomy and to obtain new insights into the pathophysiology of the hypoperfusion areas. Further studies should be done in stroke patients through the intact skull to standardise this method for early diagnosis of acute deficit in cerebral perfusion.

[Dissection of the extracranial vertebral artery. Color duplex ultrasound findings and follow-up of 20 patients]

AIM

To assess the diagnostic potential of duplex color-flow imaging in the evaluation of extracranial vertebral artery dissection. In 15 of 20 patients (75%), the dissection was related to trauma.

METHOD

Over the last six years, we evaluated 20 consecutive patients aged 18 to 59 years with 24 extracranial vertebral artery dissections (four occurring bilaterally). The examinations were performed with a color Doppler imaging system using a 7 MHz transducer. Angiography was done in 18 patients, confirming the diagnosis.

RESULTS

In 15 patients, the diagnosis was primarily established with ultrasonography. Six vertebral arteries were dissected at the origin or in the proximal V1 segment, one in the distal V2 segment and one at the atlas loop. Most dissections occurred in the region between the V1 and V2 segments (n = 16), most often at the entrance of the artery into the transverse foramen of the C6 vertebra (n = 11). Typical ultrasonographic findings were irregular stenosis, dissecting membrane with true and false lumen, localized increase in diameter of the artery, pseudoaneurysm, intramural hematoma and tapering stenosis with distal occlusion. The diagnosis of dissection in the V3 segment was based on indirect signs such as high resistance flow pattern and decreased diastolic flow velocity. In follow-up examinations, marked resolution of pathological findings were found in 17 cases (70.8%). Two occlusions were completely recanalized.

CONCLUSION

Duplex color-flow imaging is a valuable noninvasive method for early diagnosis of extracranial vertebral artery dissection and for follow-up examinations.

Evaluation of extracranial vertebral artery dissection with duplex color-flow imaging

BACKGROUND AND PURPOSE

We describe the diagnostic potential of duplex color-flow imaging in the evaluation of extracranial vertebral artery dissection.

METHODS

Twenty patients with 24 extracranial vertebral artery dissections (four bilateral) were examined with duplex ultrasonography over a period of 6 years. Color-flow imaging was carried out in 16 of these patients. In 15 patients (75%), the dissection was temporally related to trauma. Angiography was available in 18 patients, confirming the diagnosis.

RESULTS

In 15 patients, the diagnosis was primarily established with ultrasonography. Five patients with a dissection were referred for follow-up color-flow examinations. Six vertebral arteries were dissected at the origin or in the proximal V1 segment, one in the distal V2 segment, and one at the atlas loop. In contrast to other studies, the most frequent localization of the dissection in our patients was the region between the V1 and V2 segments (n = 16), where the most typical dissection site was the entrance of the artery into the transverse foramen of the C6 vertebra (n = 11). Typical ultrasonographic findings were irregular stenosis, dissecting membrane with true and false lumen, localized increase in diameter of the artery, pseudoaneurysm, intramural hematoma, and tapering stenosis with distal occlusion. In follow-up examination, a good regression of pathological findings was found in 17 dissections (70.8%). Two occlusions were completely recanalized.

CONCLUSIONS

Extracranial vertebral artery dissections can be diagnosed noninvasively with duplex color-flow imaging. It is therefore a useful method for early diagnosis and follow-up examination.

Color Doppler imaging of basal cerebral arteries: normal reference values and clinical applications

Transcranial color-coded duplex ultrasonography is a new diagnostic procedure allowing the visualization of major intracranial vessels. The purpose of this report is to describe this method and to evaluate its practical potential in the routine examination of basal cerebral arteries. The results from the examination of 96 patients are presented. By means of color coding of Doppler frequencies, the major intracranial vessels were identified by nature of their anatomic location with respect to the echogenic brainstem structures in all subjects. The average maximal systolic velocity was, in the middle cerebral artery, 108 +/- 15 cm/s; in the anterior cerebral artery, 96 +/- 15; in the posterior cerebral artery, 76 +/- 16; and in the basilar artery, 59 +/- 17 cm/s. The determination of the angle between the ultrasonic beam and the examined vessel improved the accuracy of flow velocity measurements in comparison with conventional transcranial Doppler ultrasonography. The exact measurement of blood flow velocity in several segments of the visualized vessel proved helpful in the assessment of pathologic findings, especially in differentiation between a stenosis of the intracranial vessel and a vasospasm.

Quantitative measurements of blood flow velocity in basal cerebral arteries with transcranial duplex color-flow imaging. A comparative study with conventional transcranial Doppler sonography

Transcranial duplex color-flow imaging is a new diagnostic method that allows visual display of blood flow in the basal cerebral arteries. This method allows determination of and correction for the Doppler angle of insonation. Conventional transcranial Doppler sonography has no imaging component and assumes a 0-degree Doppler angle for the calculation of flow velocities. The magnitude of the angle of insonation and the effect on flow velocity estimates have not been clearly defined. In order to evaluate the angle of insonation and the effect of angle correction on velocity readings, 50 patients referred for evaluation of cerebrovascular disease were studied. The mean age was 45 years (range, 24-62 yr). All were examined with conventional transcranial Doppler and transcranial duplex color-flow imaging. Specific vessels of the circle of Willis were identified by location, course, and direction of flow on color-flow images and by depth, direction of flow, and transducer orientation with conventional Doppler sonography. Visually controlled measurements of the Doppler angle of insonation were made by color-flow imaging. The data show that the mean angle of insonation was 33 degrees (+/- 15) in the middle cerebral artery, 35 degrees (+/- 17) in the anterior cerebral artery, 45 degrees (+/- 18) in the posterior cerebral artery, and 15 degrees (+/- 14) in the basilar artery. Angle-corrected peak systolic flow velocities were higher in all vessel segments (middle cerebral = 15%, anterior cerebral = 18%, posterior cerebral = 30%, and basilar = 3%), compared to uncorrected velocity readings by conventional Doppler sonography.(ABSTRACT TRUNCATED AT 250 WORDS)

[Transcranial color-coded duplex ultrasound--possibilities and limits of this method in comparison with conventional transcranial Doppler ultrasound]

The purpose of this report is to describe, based on the experience with 50 patients, transcranial colour-coded duplex ultrasonography and to evaluate its practical potential in the routine examination in comparison with conventional transcranial Doppler ultrasonography. Under visual control, the Doppler angle between the ultrasonic beam and the flow direction can be adjusted. The mean angle of incidence in the middle cerebral artery was 33 degrees +/- 15 degrees, in the anterior cerebral artery 35 degrees +/- 17 degrees, in the posterior cerebral artery 45 degrees +/- 18 degrees and in the basilar artery 15 degrees +/- 14 degrees. The measurements of blood flow velocity under consideration of the angle of incidence resulted in 15%, 18%, 30% and 3% respectively higher velocity values. Examples of pathologic findings demonstrate the practical potential of this noninvasive method.

Advantages of color Doppler imaging for the evaluation of vertebral arteries

Assessment of the vertebral arteries is often difficult with conventional duplex ultrasonography. This study of 60 patients aimed to determine the potential advantages of color Doppler imaging over conventional duplex ultrasonography in the evaluation of vertebral arteries, specifically three extracranial segments of these vessels. Both methods allowed visualization of the vertebral artery in the midcervical course (V2 and distal V1 segments) in all subjects. Color Doppler imaging appeared more effective for visualization of the V0 and the proximal V1 segments (on the right side in 88% of patients and on the left side in 73%). Conventional duplex ultrasonography imaged the ostium on the right side in 80% of patients and on the left side in 65%, but was difficult and time-consuming. Visualization at the atlas loop (V3 segment) was rarely successful with duplex sonography, whereas color Doppler imaging visualized the vertebral artery on the right side in 87% of patients and on the left side in 85%. Color Doppler imaging allows better visualization of the proximal and distal segments of the vertebral arteries, compared to conventional duplex ultrasonography.

Additive insulinotropic effects of exogenous synthetic human gastric inhibitory polypeptide and glucagon-like peptide-1-(7-36) amide infused at near-physiological insulinotropic hormone and glucose concentrations

Gastric inhibitory polypeptide (GIP) and glucagon-like peptide-1-(7-36) amide (GLP-1) are glucose-dependent insulinotropic gut hormones that may explain the greater insulin secretory response with oral compared to i.v. glucose (incretin effect). To study their individual and combined contributions, in eight healthy volunteers, on separate occasions, synthetic human GIP (1 pmol/kg.min) and/or GLP-1 (0.3 pmol/kg.min) or placebo were infused i.v. (-30 to 120 min), while at 0 min, a glucose infusion "isoglycemic" to the profile after an oral glucose load of 50 g/400 mL was started. After the administration of 50 g oral glucose, immunoreactive GIP rose several-fold to 337 +/- 43 pmol/L, while there was only a transient (10-30 min) and moderate increment in immunoreactive GLP-1 (from basal, 25-30, to 41 +/- 4 pmol/L). Isoglycemic i.v. glucose infusions led to smaller B-cell responses (estimated incretin effect, 41 +/- 5%). With single infusions of GIP or GLP-1 (circulating concentrations, 464 +/- 73 and 54 +/- 3 pmol/L, respectively), B-cell responses were significantly augmented compared to i.v. glucose alone and were no longer significantly different from those after oral glucose. The combination of GIP and GLP-1 led to B-cell responses that were significantly higher than those with either hormone alone (additive mode of cooperation). Plasma GIP concentrations were similar after endogenous secretion (oral glucose) and i.v. infusion, while exogenously administered GLP-1 led to plasma levels that were maintained at an elevated level for a longer period during exogenous infusion than after stimulation by oral glucose. When, in seven volunteers, a lower dose (0.15 pmol/kg.min) of GLP-1 was infused during isoglycemic glucose infusion experiments only for the duration of elevated plasma levels in the oral glucose challenges (0-30 min), a significant, but transient, increment in insulin and C-peptide concentrations was observed, which was equivalent to 26 +/- 10% of the estimated incretin effect. Therefore, in conclusion, circulating GIP seems to make a major contribution to the incretin effect after oral glucose, and GLP-1 appears to mediate a smaller proportion. GIP and GLP-1 can interact in an additive manner in normal man.

Duplex ultrasonography of vertebral arteries: examination, technique, normal values, and clinical applications

A technique for the imaging of vertebral arteries at their origins and along the longitudinal extracranial course is described. The results of the examination of 108 normal vertebral arteries are shown. The vertebral artery could be distinguished in the pretransverse and intertransverse segment C5-C6 in 100%. The average diameter of the vessel was 3.81 +/- 0.46 mm on the right and 3.88 +/- 0.47 on the left side. The average maximal systolic velocity was 43.0 +/- 8.9 cm/s on the right and 43.3 +/- 9.6 on the left side. In 81% of the cases the vertebral origin could be located on the right and in 65% of the cases on the left side. The technical quality of visualization, especially of the vertebral origin, was greatly influenced by the depth of the examined structure. Examples of pathologic findings, such as hypoplasia, stenosis, and occlusion, demonstrate the practical possibilities of this noninvasive method.

Lack of effect of synthetic human gastric inhibitory polypeptide and glucagon-like peptide 1 [7-36 amide] infused at near-physiological concentrations on pentagastrin-stimulated gastric acid secretion in normal human subjects

Gastric inhibitory polypeptide (GIP) and glucagon-like peptide 1 [7-36 amide] (GLP-1) are glucose-dependent insulinotropic gut hormones. Under experimental conditions, both have been shown to reduce stimulated gastric acid secretion. To study their individual and combined effects on pentagastrin-stimulated (0.1 micrograms/kg/h from -90 to 120 min) gastric volume, acid and chloride output, on separate occasions, synthetic human GIP (1 pmol/kg/min) and/or GLP-1 [7-36 amide] (0.3 pmol/kg/min) or placebo (0.9% NaCl with 1% albumin) were infused intravenously (from -30 to 120 min) in 9 healthy volunteers. At 0 min, a glucose infusion was started that mimicked the glycemic profile after an oral glucose load of 50 g/400 ml and allowed for the glucose-dependent insulinotropic action of GIP and GLP-1 [7-36 amide]. Pentagastrin stimulated acid output significantly, but neither GIP nor GLP-1 [7-36 amide] either alone or in combination, reduced pentagastrin-stimulated gastric acid secretion. The circulating concentrations of GIP and GLP-1 [7-36 amide] obtained at steady state during exogenous administration of synthetic peptides were similar to or higher than those reached after oral glucose (endogenous secretion). In conclusion, (penta)gastrin-stimulated gastric acid secretion is not inhibited by physiological circulating concentrations of GIP or GLP-1 [7-36 amide]. Therefore, the insulinotropic action of these intestinal hormones is physiologically more important than their possible role as enterogastrone.