Evaluation of lumbar lordosis in symptomatic individuals and comparative analysis of six different techniques: a retrospective radiologic study.

PURPOSE: The aim of this study; evaluate lumbar lordosis (LL) in symptomatic individuals with six different techniques and to examine the techniques comparatively. Thus, to provide an overview of lumbal lordosis and techniques. METHODS: Cobb L1-L5, Cobb L1-S1, Posterior Tangent, tangential radiologic assessment of lumbar lordosis (TRALL), vertebral centroid measurement of lumbar lordosis (CLL) and Risser Ferguson measurement techniques were used to assess LL from radiographs of 175 symptomatic adults. Correlations between techniques and relationship between the measurements obtained, gender and age were analyzed. Also interclass correlation (ICC) analyzed. Bland-Altman plots were performed to compare the techniques with Cobb. RESULTS: ICC for all methods were greater than 0.96. For each method, no difference in LL was observed with respect to gender or age (p > 0.05). High positive correlation was observed between the Risser Ferguson, Posterior Tangent, Cobb L1-L5, Cobb L1-S1 and CLL techniques (p < 0.001), and moderate positive correlation between TRALL and all other techniques (p < 0.001). CONCLUSION: In this study, it was found that the mean lumbar lordosis values of symptomatic participants were lower than most of the other asymptomatic studies in the literature and there was no significant difference in lumbar lordosis values in terms of gender and age in symptomatic individuals. Based on statistical findings, Risser Ferguson can be used to assess LL. These results and the data obtained as a result of the comparative examination of techniques according to age groups and gender will benefit clinicians and those working in the field by providing a better understanding LL.

Morphometric analysis of the infratemporal fossa using three-dimensional (3D) digital models.

PURPOSE: The infratemporal fossa contains important neurovascular components and is directly related to other anatomical regions and structures. The morphometric distances between the bones forming its borders have not been thoroughly investigated. The aim of this study was to determine the morphometry of the infratemporal fossa. METHODS: 3D models of the skull of 83 individuals were reconstructed from DICOM datasets, from which length, depth and width measurements were determined and compared between genders and the right and left sides. RESULTS: All measurements obtained were significantly different between males and females. There were also significant differences between the left and right sides for depth and width measurements. CONCLUSION: This is the first study to determine and investigate measurements of the infratemporal fossa; as such it provides a comprehensive view of the morphology of the fossa. It provides valuable information for surgical interventions and differential diagnoses of pathologies in this region, as well as enhancing its understanding in medical education.

Assessment of scapular morphometry / Evaluación de la morfometría escapular

The current study was undertaken to assess the incidence of different types of suprascapular notch, acromion dimensions and the lower and upper scapular angles. The suprascapular notch and variations of the acromion are clinically important in suprascapular nerve compression and subacromial impingement. Measurements were taken from 73 Anatolian dry scapulae of unknown age or sex. The suprascapuar notch was classified according to that of Rengachary et al. (1979). Its width and depth, the distance between supraglenoid tubercle and the deepest point of notch, as well as the upper and lower scapular angles were also determine measured. The type of acromion was assessed according to shape (type I (cobra), type II (square), type III (intermediate)) and tilt (type I (flat), type II (curve). Acrmion length and the distance between acromion and coracoid process were also measured. The frequency of different types of suprascapular notch were type I (28.8 %), type II (23.3 %), type III (13.7 %), type IV (20.5 %), type V (2.7 %), type VI (5.5 %)and absence (5.5 %). Acromion type were type I (45.5 %), type II (7.5 %) and type III (47.0 %), acromion tilt type I (15.2 %), and type II (84.8 %). An understanding of the association between the anatomical structures of the scapula and morphometric measurements is clinically important.

En este trabajo se evaluó la incidencia de diferentes tipos de incisura supraescapular, dimensiones de acromion y los ángulos escapulares superior e inferior. La incisura supraescapular y las variaciones del acromion son clínicamente importantes en la compresión del nervio supraescapular y el pinzamiento subacromial. Las mediciones se tomaron de 73 escápulas secas de Anatolia, de edad y sexo desconocidos. La incisura supraescapular se clasificó según Rengachary et al. (1979). Se determinaron también el ancho y la profundidad, la distancia entre el tubérculo supraglenoide y el punto más profundo de la incisura, así como los ángulos escapulares superior e inferior. El tipo de acromion se evaluó de acuerdo con la forma [tipo I (cobra), tipo II (cuadrado), tipo III (intermedio)] y la inclinación [tipo I (plano), tipo II (curvo)]. También se midieron la longitud del elemento y la distancia entre el acromion, como así también el proceso coracoide. La frecuencia de los diferentes tipos de incisura supraescapular fueron: tipo I (28,8 %), tipo II (23,3 %), tipo III (13,7 %), tipo IV (20,5 %), tipo V (2,7 %), tipo VI (5,5 %) y ausencia (5,5 %). Los tipos de acromion fueron: tipo I (45,5 %), tipo II (7,5 %) y tipo III (47,0 %), tipo de inclinación de acromion I (15,2 %) y tipo II (84,8 %). En conclusión, el conocimiento de la asociación entre las estructuras anatómicas de la escápula y las mediciones morfométricas es clínicamente importante.

Three-dimensional analysis of the proximal humeral and glenoid geometry using MicroScribe 3D digitizer.

PURPOSE: To understand the geometry of the proximal humerus and glenoid fossa to facilitate the design of components used in shoulder arthroplasty. The aim is to evaluate the geometry of the proximal humerus and glenoid fossa and their relationship using a MicroScribe 3D digitizer. METHODS: Scans and measurements were obtained from 20 pairs of dry proximal humeri and scapulae [10 female and 10 male cadavers: median age 81 years (range 70-94 years)] using a MicroScribe 3D digitizer and Rhinoceros software. RESULTS: Means (±SD) of humeral inclination, medial wall angle of the bicipital groove, and radius of the humeral head values were 135 ± 11°, 39 ± 19°, and 14 ± 3 mm, respectively. Means (±SD) of glenoid height and width were 35 ± 4 and 26 ± 4 mm, while the means (±SD) of the angles of glenoid inclination, retroversion, and rotation were 87 ± 32°, 96 ± 10°, and 9 ± 6°, respectively. A significant difference in glenoid height (P ≤ 0.002) and width (P ≤ 0.0001) was observed between males and females, despite them having almost an identical radius of the humeral head, glenoid inclination, retroversion, and angle of rotation. There was also a significant difference (P ≤ 0.01) in the angle of glenoid retroversion between the right and left sides. CONCLUSIONS: Using a MicroScribe 3D digitizer, the glenoid fossa was observed to be significantly smaller in females than males; furthermore, there was a difference in glenoid retroversion between the right and left sides.

How well do contoured superior midshaft clavicle plates fit the clavicle? A cadaveric study.

BACKGROUND: Given the degree of variation in clavicular morphology, 4 clavicle plating systems were examined for their congruity as superior, midshaft, anatomic clavicle (SMAC) plates in a cadaveric study. METHODS: SMAC plates from 4 manufacturers were applied to 79 dry right human clavicles. Two systems offered multiple (4) variations of plates (MP), 1 offered two variations (TP), and 1 had a single plate (SP). Two examiners applied and clamped the best-fitting plate from each system onto each of the 79 clavicles and then graded them: 1, poor fit; 2, good fit; and 3, anatomic fit. Each examiner repeated the process to assess intraobserver and interobserver reliability. The scores were averaged to produce a final score for each system for each clavicle. RESULTS: The MP systems scored the highest (32%-37% anatomic, 54%-63% good, 5%-8% poor), followed by the TP system (30% anatomic, 53% good, 17% poor), and finally the SP system (9% anatomic, 59% good, 32% poor). Of note, clavicular length significantly correlated with a higher degree of conformity in all plating systems (Spearman rank correlation P < .05 for each system). In clavicles longer than 150 mm, the MP and TP systems performed identically, with the SP system close behind. Contouring of the plate is needed in 73% of cases overall. CONCLUSION: Plating systems with multiple plate shape variations are more advantageous when dealing with smaller-sized clavicles, typically in females. However, when dealing with larger clavicles, there was no real difference.

Evaluation of the coracoid and coracoacromial arch geometry on Thiel-embalmed cadavers using the three-dimensional MicroScribe digitizer.

BACKGROUND: Understanding the geometry of the coracoid and coracoacromial arch will improve surgical intervention in shoulder surgery. METHODS: Thirty pairs of scapulae from 20 female and 10 male deceased donors, average age of 82 years (range, 62-101 years), were scanned and measurements taken using the 3-dimensional (3D) MicroScribe digitizer (Immersion Corp, San Jose CA, USA) and Rhino software (McNeel North America, Seattle, WA, USA). RESULTS: The following mean angles were determined: coracoid slope, 44° ± 11°; coracoid deviation, 35° ± 6°; coracoid root to glenoid, 115° ± 14°; coracoid head to glenoid, 110° ± 11°; scapular spine angle, 35° ± 6°; and coracoacromial angle, 63° ± 9°. The following mean distances were also determined: coracoid height, 10 ± 3 mm; coracoacromial distance, 42 ± 7 mm; coracoacromial arch height, 20 ± 5 mm; and coracoid (anterior, 29 ± 6 mm; middle, 20 ± 4 mm; posterior tip, 18 ± 6 mm) to the glenoid fossa. The coracoid root-to-glenoid angle was significantly correlated with the coracoacromial angle. In addition, coracoid slope was significantly correlated with coracoid root-to-glenoid angle and also with coracoid deviation. Left shoulders had a significantly higher coracoid-to-glenoid angle (P < .029) than right shoulders. Women had a significantly higher coracoid root-to-glenoid angle than men (P < .042), and men had a significantly higher coracoid deviation (P < .011), anterior (P < .006) and posterior coracoid-to-glenoid distances (P < .03), and coracoacromial arch height (P < .07) than women. CONCLUSIONS: This is the first time that the 3D MicroScribe digitizer has been used to evaluate the geometry of the coracoacromial arch and coracoid process.

Thiel embalming method for cadaver preservation: a review of new training model for urologic skills training.

The use of endourology training models is on the rise. Surgical practice is moving toward a more minimally invasive approach and deficits in surgical exposure by enforcement of the European Working Time Directive call for simulation models to be anatomically sound. Thiel-embalmed cadavers have been found to demonstrate efficacy in tissue quality, elasticity, and handling in addition to playing a role in teaching and training. This review summarizes the current status of the Thiel method and its role in urologic skills training.

A pilot study comparing the use of Thiel- and formalin-embalmed cadavers in the teaching of human anatomy.

Formalin had traditionally been used to preserve human material to teach gross anatomy. In 2008 the Centre for Anatomy and Human Identification (CAHID) at the University of Dundee embarked on the use of the Thiel method of embalming. The aim of this pilot study was to assess the difference between formalin-embalmed cadavers (FEC) and Thiel-embalmed cadavers (TEC) used for teaching and surgical training. Three different questionnaires were prepared for data collection from undergraduate and postgraduate students and clinical staff. All undergraduate and postgraduate students as well as clinical staff commented on the appearance of the TEC. There was no overall consensus concerning the use of TEC, some respondents preferred TEC for the entire dissection, some only for certain areas such as the musculoskeletal system. On a technical level TEC were considered less hazardous then FEC by one-third of participants with fewer than 10% regarding TEC as more irritating than FEC. Psychologically, 32.7% of undergraduate students expressed the view that TEC made them feel more uncomfortable compared with FEC because of their life-like appearance. However, 57.1% of undergraduate students encountered the same uncomfortable feelings when viewing both TEC and FEC. The use of Thiel-embalmed cadavers to teach anatomy has an added value, though further research is required over longer periods of time to identify its best usage.

Growth of the human ilium: the anomalous sacroiliac junction.

Despite the major anatomical importance of the human ilium in medicine and forensic investigations, little is understood about its pattern of growth. This study was conducted to investigate the changes in the surface area of the human ilium from birth through to adolescence in 80 human ilia. A photographic image of the pelvic surface of each bone was taken and examined using an image quantification package. The surface areas of four regions of interest were quantified: the auricular, post-auricular (PA), iliac fossa, and whole pelvic surface of the ilium. The results highlight a rapid increase in surface area for all regions in the first few years after birth which continues, albeit at a slower rate, until ∼4 years of age when the rate of growth is further reduced. Although the ilium and its various components continue to grow between 5 years and puberty, the rate of growth is markedly reduced until puberty when growth of the pelvis again increases. Interestingly, analysis of the differential growth of the auricular region compared with the PA region throughout development suggests that the PA region exhibits more advanced growth. This may indicate that its role in structural development for the purposes of preparation and maintenance of bipedal stance and locomotion may have been previously poorly understood.

A qualitative assessment of human cadavers embalmed by Thiel's method used in laparoscopic training for renal resection.

Human cadaveric tissue is the fundamental substrate for basic anatomic and surgical skills training. A qualitative assessment of the use of human cadavers preserved by Thiel's method for a British Association of Urological Surgeons-approved, advanced laparoscopic renal resection skills training course is described in the present study. Four trainees and four experienced laparoscopic surgeons participated in the course. All participants completed a five-point Likert scale satisfaction questionnaire after their training sessions. The quality of cadaveric tissue and the training session were assessed with particular emphasis placed on the ease of patient positioning, the ease of trocar placement, the preservation of tissue planes, the ease of renal pedicle dissection, and the quality of tissue preservation. All of the participants highly rated the quality of the cadaveric tissue embalmed by Thiel's method (mean scores for quality on the five-point Likert scale were 4.5 and 4.3 by the trainees and experienced laparoscopic surgeons, respectively). All of the steps of laparoscopic renal resection were rated 4.0 or more on the Likert scale by both trainees and faculty members. The initial response rates for using a human cadaver embalmed by Thiel's method as a training tool for laparoscopic nephrectomy showed encouraging results. The performance of a laparoscopic nephrectomy on a human cadaver embalmed by Thiel's method bears close resemblance to real laparoscopic nephrectomy procedures, and thus demonstrates added advantages to the previously reported models.

The posterior longitudinal ligament and peridural (epidural) membrane.

The posterior longitudinal ligament (PLL) is described as having deep and superficial layers, though recent studies have suggested that there may be three layers. Additional membranous structures have been reported, although there is no consensus as to their presence or morphology. The vertebral canal and dural sac were opened and the spinal nerve roots and spinal cord removed. The anterior dural ligaments were sectioned at their attachment to the PLL and the dura mater freed from the posterior surface of the vertebral bodies. The borders of the PLL were identified and the superficial and deep layers separated. The PLL is a wide band in the cervical region becoming more denticulate inferiorly, the widest parts being attached to the intervertebral discs (IVD) and adjacent vertebral body where the superficial and deep layers could not be separated. A continuous well developed peridural membrane attaching to the pedicles was present anterior to the deep PLL as well as a separate, thin, incomplete layer in 6 of 18 cadavers, covering the posterior surface of the superficial PLL.

The anterior visceral branches of the abdominal aorta and their relationship to the renal arteries.

Variations in the anatomy of the abdominal aorta and its branches are of interest as vessel geometry not only determines flow dynamics, but is also crucial in the pathogenesis of vascular disease. The relationship between the anterior visceral and renal arteries is important when undertaking diagnostic arteriography and endovascular interventions. To examine these relationships, the length of the abdominal aorta was determined and measurements taken of the position of origin of the celiac artery, superior mesenteric artery (SMA), inferior mesenteric artery (IMA) and renal arteries, as well as the three-dimensional projection of each vessel from the aorta. The mean level of bifurcation of the aorta was at the lower third of the body of L4, with the celiac artery, SMA, renal arteries and IMA arising at the level of the T12/L1 intervertebral disc, upper third of the body of L1, lower third of the body of L1 and lower third of the body of L3, respectively. The horizontal projection of the celiac artery, SMA and IMA was to the left of the midline; in the sagittal plane, the celiac artery and SMA projected anteriorly and the IMA posteriorly; in the coronal plane all vessels projected inferiorly, with the SMA to the right and the IMA to the left. The celiac artery, SMA and both renal arteries all arise from the proximal half of the abdominal aorta within 45 mm of each other, with the origins of the renal arteries being remarkably consistent. It is concluded that the celiac artery and SMA are both useful landmarks for determining the position of the renal arteries.

Effects of cagA+ and cagA- strains of Helicobacter pylori on the human gastric mucus layer thickness.

BACKGROUND: Infection with cytotoxin-associated gene A (cagA) Helicobacter pylori is associated with severe gastric diseases, with contradictory views being expressed concerning the effect of H. pylori on the gastric mucus thickness. The aim of the present study was to differentiate between the effect of cagA+ and cagA- strains on gastric mucus thickness. METHODS: Ninety-nine patients without peptic ulcers who were not on medication were randomly recruited from consecutive endoscopy clinics: six biopsies (five antral, one body) were obtained from each patient. Cryostat sections (18 microm) were cut and stained using the modified periodic acid-Schiff/Alcian blue technique. Mucus thickness was measured using computer-assisted light microscopy. The H. pylori status was assessed by histology, Campylobacter-like organism (CLO)test and culture, and cagA+ status determined by polymerase chain reaction (PCR). RESULTS: There was no significant difference (P = 0.784) in mean mucus thickness between cagA+ (52.7 +/- 1.2 microm, n = 10), cagA- (46.6 +/- 1.1 microm, n = 18) or H. pylori-negative patients (51.3 +/- 1.1 microm, n = 30). In cagA- patients, mucus thickness was significantly reduced with increased H. pylori colonization density, Spearman (r(s)) = -0.805, P < 0.0001. In contrast, in cagA+ patients there was a weak positive, but not significant, association between mucus thickness and H. pylori colonization density, r(s) = 0.333, P = 0.381. CONCLUSIONS: The human gastric mucus thickness is not affected by infection with cagA+ or cagA- strains of H. pylori compared with uninfected. Although a trend of increased mucus thickness with cagA+ infection was observed.

Effect of patellar tendon shortening on tracking of the patella.

BACKGROUND: Although 10% postoperative patellar tendon shortening after bone-patellar tendon-bone autograft reconstruction of the anterior cruciate ligament has been reported, there are no published studies assessing the effect of shortening on patellofemoral joint biomechanics under physiological loading conditions. PURPOSE: To investigate the influence of patellar tendon shortening on patellofemoral joint biomechanics. STUDY DESIGN: Controlled laboratory study. METHODS: The authors evaluated the patellofemoral contact area, the location of contact, and the patellofemoral joint reaction force and contact stresses in 7 cadaveric knees before and after 10% patellar tendon shortening. Shortening was achieved using a specially designed device. Experimental conditions simulating those occurring during level walking were employed: physiological quadriceps loads and corresponding angles of tibial rotation were applied at 15 degrees , 30 degrees , and 60 degrees flexion of the knee. Patellofemoral joint contact areas were measured before and after shortening using the silicone oil-carbon black powder suspension squeeze technique. RESULTS: After patellar tendon shortening, patellofemoral joint contact areas were displaced proximally on the patellar surface and distally on the femoral surface. Although the contact area increased by 18% at 15 degrees of knee flexion (P = .04), no significant change occurred at 30 degrees or 60 degrees of knee flexion (P > .05). Patellofemoral contact stress remained unchanged after patellar tendon shortening (P > .05) at each flexion angle. CONCLUSION: Our results suggest that a 10% shortening of the patellar tendon does not alter patellar contact stresses during locomotion. It is not clear whether apparent changes in contact location in all positions and contact area at 15 degrees would have clinical consequences.

Helicobacter pylori. Basics and clinical overview.

The discovery of Helicobacter pylori (H. pylori) has greatly changed the approach to the management of peptic ulcer disease and gastric cancer. A sound knowledge of the basics of H. pylori is an important aid in the diagnosis and treatment of clinical conditions associated with this infection. Gastric carcinoma is estimated to be the world's second most common cancer as a cause of death. It is hoped that gastric cancer can be prevented by H. pylori eradication; however, this issue is still under investigation. Active research is ongoing to highlight the mechanisms by which H. pylori leads to severe gastric diseases as well as finding associations with extra-gastric diseases.

Human gastric mucosal hydrophobicity does not decrease with Helicobacter pylori infection or chronological age.

BACKGROUND AND AIMS: Infection with cytotoxin-associated gene A (cagA) Helicobacter pylori is associated with severe gastric diseases. Previous studies in humans have reported a decreased gastric hydrophobicity with H pylori infection. The aim of the present study was to differentiate between the effect of cagA+ and cagA- strains on gastric mucus hydrophobicity. METHODS: One hundred patients without peptic ulcers and not on medication were randomly recruited from endoscopy clinics; each patient had six biopsies. Contact angle measurements were performed using a goniometer assisted by computer software. H pylori status was assessed by histology, Campylobacter-like organism test and culture, and cagA+ status was determined by polymerase chain reaction. RESULTS: In age- and sex-matched patients, there was no significant difference (P=0.27) in contact angle between H pylori-positive (61+/-2.8 degrees ) and H pylori-negative patients (65.5+/-3.0 degrees ). There was also no significant difference (P=0.36) in contact angle among H pylori-negative, cagA- and cagA+ patients (65.5+/-3.0 degrees , 58.6+/-3.6 degrees and 63.4+/-4.9 degrees , respectively). However, a trend of increased mean contact angles in cagA+ compared with cagA- and H pylori-negative patients was observed in patients 50 years and younger (68.3+/-8.3 degrees , 61.1+/-6.1 degrees and 63.6+/-2.2 degrees , respectively; P=0.70) and in patients without atrophy (71.1+/-8 degrees , 59.6+/-4 degrees and 66+/-2 degrees , respectively; P=0.30). In addition, there was no significant correlation between contact angles and patient age (r=0.104, P=0.306). CONCLUSIONS: The present study shows that H pylori infection and the chronological age have no effect on the gastric mucus hydrophobicity, but it highlights a trend of increased mucus hydrophobicity with cagA+ infection that needs to be supported by future studies.

Selectively attenuating soft tissues close to sites of inflammation in the peritalar region of patients with rheumatoid arthritis leads to development of pes planovalgus.

OBJECTIVE: To compare the 3-dimensional (3D) orientation of the tibiotalar, tibiocalcaneal, and intertarsal joints in cadaveric specimens following structural weakening to predetermined ligaments in the peritalar region and medial ankle tendons under axial loads and simulated calcaneal valgus deformity. METHODS: Eight fresh-frozen, unembalmed human lower leg and foot specimens were placed in a materials testing machine. The mid-stance period of gait was simulated and the 3D orientation of the tibiotalar, tibiocalcaneal, and intertarsal joints was measured using an electromagnetic motion analysis system. Specimens were then axially loaded at 840 N for 5400 cycles with the calcaneus in its initial orientation and under simulated valgus conditions using a heel wedge following attenuation (multiple stab incisions) of selected ligaments (tibionavicular, anterior tibiotalar and tibiocalcaneal portions of the medial deltoid ligament, the inferior calcaneonavicular ligament, and the superomedial calcaneonavicular ligament) or tendons (tibialis posterior, flexor digitorum longus, and flexor hallucis longus). The joint orientation measurements were then repeated and compared with baseline intact measurements. RESULTS: Pes planovalgus was observed in 6/8 specimens following testing. The tibiotalar, tibiocalcaneal, talonavicular, and calcaneocuboid joints were more dorsiflexed, everted, and externally rotated following either ligament or tendon compromise. The changes in orientation were small but showed consistent patterns with the smallest changes (typically < 1 degrees ) for the transverse plane and largest (up to 3.5 degrees ) for the frontal plane. The magnitude of change was similar for the tibiotalar and tibiocalcaneal joints, largest for the talonavicular joint, and smallest for the calcaneocuboid joint for both ligament and tendon compromise. The orientation of the talocalcaneal joint was more plantarflexed and everted relative to baseline, for both the ligament and tendon compromise with < 1 degrees of change in orientation about the transverse plane. Under simulated valgus heel conditions, joint orientation was further increased especially about the frontal plane in the direction of eversion. The smallest changes were noted for the calcaneocuboid joint (approximately 1 degrees ), similar change (approximately 2-3 degrees ) for the tibiotalar, tibiocalcaneal and talocalcaneal joints, and the largest changes (> 3 degrees ) for the talonavicular joint. There were no observed differences in the magnitude of change between ligament or tendon condition. CONCLUSION: Selective attenuation to either the ligaments supporting the tibiotalar, talocalcaneal, and talonavicular joints or the medial ankle tendons followed by cyclic loading results in small but important changes in the orientation of the tarsal bones consistent with the development of pes planovalgus.

The association between cagA+ H. pylori infection and distal gastric cancer: a proposed model.

Cytotoxin-associated gene A (cagA)+ infection is associated with an increased risk of distal gastric cancer. The aim was to determine the effect of Helicobacter pylori (HP) on gastric mucus thickness, hydrophobicity, and PGE2 and their relation to colonization density. Ninety-nine patients were recruited (69 HP- and 30 HP+: 10 cagA+, 18 cagA-, 2 undetermined) and six biopsies were obtained from each patient. Mucus thickness, hydrophobicity, PGE2, and colonization density were determined. HP status was assessed by histology and culture; cagA+ was determined by PCR. In age- and sex-matched patients, PGE2 was greater in PH+ than HP- (P = 0.04), with cagA+ having higher PGE2 than HP- patients (P = 0.031). No differences were observed in mucus thickness (P = 0.717) or hydrophobicity (P = 0.27) between HP+ and HP- patients. However, cagA+ showed a nonsignificant trend of increase in mucus thickness (P = 0.784) and hydrophobicity (P = 0.30) compared to cagA- and HP- patients. cagA+ colonization density was weakly correlated with increased thickness (r = 0.333, P = 0.381), whereas cagA- density was inversely correlated with thickness (r = -0.805, P = 0.0001). A model suggesting the possible changes induced by cagA+ infection is proposed which explains the high association of cagA+ with distal gastric cancer. If supported by large multicenter studies, this could form the basis for the development of new therapies directed at the mucous layer to eradicate HP and thus reduce the risk of gastric cancer.

cagA+ Helicobacter pylori induces greater levels of prostaglandin E2 than cagA- strains.

cagA+ Helicobacter pylori (HP) infection is associated with an increased risk of distal gastric cancer. Previous studies investigating the effect of HP infection on prostaglandin E2 (PGE2) levels have not differentiated between cagA+ and cagA- strains and consequently have produced contradictory results. The aim was to investigate the effect of cagA+ strains on PGE2 and enhance the understanding of the mechanisms leading to gastric diseases. Hundred patients without peptic ulcers and not on medication were recruited (one later excluded) from endoscopy clinics: six biopsies were obtained from each patient. PGE2, colonization density and histology were determined. In addition, HP status was assessed by histology, CLOtest and culture with cagA+ being determined by PCR. Sixty-nine patients were HP- and 30 HP+ (10 cagA+, 18 cagA-, 2 undetermined). In age and sex-matched patients, PGE2 was significantly greater (P = 0.04) in HP+ (37.2 +/- 1.2 pg/mg per 20 min) than in HP- (22.6 +/- 1.2). In patients without atrophy, those infected with cagA+ had significantly higher (P = 0.03) PGE2 levels (53 +/- 1.1) than HP- patients (22.6 +/- 1.1) and greater levels (P = 0.29) than cagA- patients (35 +/- 1.3). In conclusion, the increased levels of PGE2 in the presence of cagA+ infection could be an important factor by which cagA+ strains enhance the gastric mucus layer protective functions leading to established colonization, gastritis and increased risk of gastric cancer. However, further evaluation with a large-scale multi-centre study is required to substantiate this hypothesis.