Phase variation in H type I and Lewis a epitopes of Helicobacter pylori lipopolysaccharide

Helicobacter pylori NCTC 11637 lipopolysaccharide (LPS) expresses the human blood group antigens Lewis x (Le(x)), Le(y), and H type I. In this report, we demonstrate that the H type I epitope displays high-frequency phase variation. One variant expressed Le(x) and Le(y) and no H type I as determined by serology; this switch was reversible. Insertional mutagenesis in NCTC 11637 of JHP563 (a poly(C) tract containing an open reading frame homologous to glycosyltransferases) yielded a transformant with a serotype similar to the phase variant. Structural analysis of the NCTC 11637 LPS confirmed the loss of the H type I epitope. Sequencing of JHP563 in strains NCTC 11637, an H type I-negative variant, and an H type I-positive switchback variant showed a C14 (gene on), C13 (gene off), and C14 tract, respectively. Inactivation of strain G27, which expresses Le(x), Le(y), H type I, and Le(a), yielded a transformant that expressed Le(x) and Le(y). We conclude that JHP563 encodes a beta3-galactosyltransferase involved in the biosynthesis of H type I and Le(a) and that phase variation in H type I is due to C-tract changes in this gene. A second H type I-negative variant (variant 3a) expressed Le(x) and Le(a) and had lost both H type I and Le(y) expression. Inactivation of HP093-HP094 resulted in a transformant expressing Le(x) and lacking Le(y) and H type I. Structural analysis of a mutant LPS confirmed the serological data. We conclude that the HP093-HP094 alpha2-fucosyltransferase (alpha2-FucT) gene product is involved in the biosynthesis of both Le(y) and Le(x). Finally, we inactivated HP0379 in strain 3a. The transformant had lost both Le(x) and Le(a) expression, which demonstrates that the HP0379 gene product is both an alpha3- and an alpha4-FucT. Our data provide understanding at the molecular level of how H. pylori is able to diversify in the host, a requirement likely essential for successful colonization and transmission.     

Correspondence

In 1813 Gantzer described 2 accessory muscles in the human forearm which bear his name (Wood, 1868; Macalister, 1875) and these have subsequently been reported with variable attachments (Wood, 1868; Macalister, 1875; Turner, 1879; Schäfer & Thane, 1894; Le Double, 1897; Dykes & Anson, 1944; Mangini, 1960; Malhotra et al. 1982; Kida, 1988; Tountas & Bergman, 1993). The accessory heads of the deep flexors of the forearm (Gantzer's muscles) have been described as 2 different small bellies which insert either into FPL or FDP. There are no previous reports which have mentioned the existence of an accessory muscle which inserts into both of the 2 deep flexors of the forearm as in the case presented here.     

The sternalis muscle in the Bulgarian population: classification of sternales

The sternalis muscle (musculus sternalis) is the name usually given to this common anatomical variant, but the terms 'episternalis', 'presternalis', 'sternalis brutorum', 'rectus thoracis', 'rectus sterni', 'superficial rectus abdominis' and 'japonicus' have also been used in the literature (for reviews see Le Double, 1879; Calori, 1888; Pichler, 1911; Blees, 1968). According to Turner (1867), Cabrolius was the first, in 1604, to describe sternalis. Nevertheless this muscle is often unknown even in clinical practice (Bailey & Tzarnas, 1999; Vandeweyer, 1999).
Thus far, investigations on the incidence of sternalis have been made both in large populations such as the American (Barlow, 1935) and small populations, for example in Taiwan (Shen et al. 1992; Jeng & Su, 1998). In Europe, all studies on the frequency of this muscle have been made amongst subpopulations in Western (e.g. Cunningham, 1888; Le Double, 1890, 1897) and Northern Europe (Gruber, 1860) although the reported frequencies have been quite different. There is a lack of information about sternalis in Eastern European populations. We therefore present data from a study on the incidence of sternalis muscle in Bulgaria.     

Lethal multiple pterygium syndrome: three consecutive cases in one family

We report on three sib fetuses with the lethal multiple pterygium syndrome (LMPS), one case occurring in a twin pregnancy. All three fetuses had a cystic hygroma and hydrops was detected by ultrasound. The classification scheme for LMPS proposed by Hall [1984] is examined. With our present state of knowledge of this syndrome, subdivision on bone-fusion types does not appear to be justified. Antenatal detection by ultrasound is possible in most pregnancies with a second affected fetus because of cystic hygroma and hydrops. In the term or near-term infant in which ultrasound has not shown cystic hygroma or hydrops, a diagnosis of Pena-Shokeir type I syndrome should be considered because pterygia are a component of that syndrome but cystic hygroma and hydrops are not.     

Prevalence of fenestrated basilar artery with magnetic resonance angiography: a transversal study

Fenestration of the basilar artery (BA) is a rare anatomical variation in comparison to those of the other intracranial arteries constituting the cerebral arterial circle. The incidence is difficult to ascertain and data vary according to type of series and modalities of detection. Basilar artery fenestration (BAF) has been reported in association with arteriovenous malformations, vascular variants, other developmental anomalies and neurovascular conflicts as a consequence of relations between the arterial branches of the BA and the nerves and other structures in the posterior cranial fossa. However, the real clinical interest of BAF is due to the possible formation of an aneurysm at the junction of the fenestrated segment and less frequently to the thrombosis of the vessels. With the aim to establish the prevalence of BAF in our population, we made a transversal pilot study of the first 200 MR angiographies performed on patients attending for the first time to control their base pathology (vascular or not). We have described three patients with this condition (representing a prevalence of 1.5 % on MR angiography) to shed additional light on this anomaly, two cases located at 1/3 proximal end (type 1-BAF) and one case located at joint 1/3 medium–1/3 distal end, locating distal to the anterior inferior cerebellar artery (type 4-BAF). In neither case was any other lesion found (i.e. aneurysm, infarctions, ischemia or thromboembolism). The pertinent clinical anatomy and embryological basis for this variation are reviewed, and the possible clinical implications and associated findings are discussed.     

Littoral cell angioma of the spleen diagnosed by endoscopic ultrasound-guided fine-needle aspiration biopsy

Littoral cell angiomas are uncommon primary vascular neoplasms that arise from the sinusoidal lining or littoral cells of the splenic red pulp, and hence are unique to the spleen. We report a case of littoral cell angioma in 34-year-old woman, which was diagnosed by endoscopic ultrasound-guided fine needle aspiration biopsy (EUS-FNAB). The cytologic features of littoral cell angiomas have been described only in three previous case reports, one of which was a bench-top aspirate. In our case, we have utilized the fine-needle aspiration samples obtained by a linear endoscopic ultrasound examination for establishing the diagnosis. The characteristic cytologic features identified on the smears along with immunohistochemical analysis performed on the compact cellblock prepared from the aspirate aided in the confirmation of the diagnosis. We suggest that EUS-FNAB is a safe and reliable method in the diagnosis of vascular lesions of the spleen.     

Fetal Hydrocephalus Caused by Cryptic Intraventricular Hemorrhage

Cryptic intracerebral hemorrhage as an etiological factor in fetal hydrocephalus has been postulated but not described at autopsy. Four fetuses with overt hydrocephalus diagnosed by in utero ultrasound examination were examined at autopsy at 19–22 weeks gestation. Although a hemorrhagic etiology was not evident on ultrasound, hemosiderin‐containing macrophages and associated reactive changes were found to obstruct the otherwise well‐formed cerebral aqueduct in all four. Coagulopathy due to thrombocytopenia was implicated in one case. Anomalies involving other parts of the body were identified in two cases, although a direct link to the hydrocephalus was not obvious. The abnormality was isolated in one case. In three cases, possible sites of hemorrhage in the ventricles were identified. This abnormality represents a significant proportion of the fetuses examined for hydrocephalus in our referral center. We discuss the importance of careful autopsy examination in the diagnosis of cryptic intracerebral hemorrhage and the implications for counseling.     

Prenatal diagnosis of short rib (polydactyly) syndrome with situs inversus

We present a case of short rib (polydactyly) syndrome in which the diagnosis was made prenatally by ultrasound examination. The more specific diagnosis of short rib (polydactyly) syndrome type III was made on the basis of findings on radiographs obtained at birth. The sonographic and radiographic features are discussed. The patient had complete situs inversus and hypospadias. The former was reported in one other case of type III and the later has not been previously reported in this entity. © 1992 Wiley-Liss, Inc.     

Expression of Lewis antigens and their precursors in gastric mucosa: relationship with Helicobacter pylori infection and gastric carcinogenesis

Lewis (Le)-associated antigens are carbohydrates that are related biochemically to the ABO blood groups, and may have a role in Helicobacter pylori adherence. To evaluate their relationship to clinicopathological outcomes, gastric Le expression, including type 1 precursor, type 1 H, Le(a), Le(b), Le(x), Le(y) and sialylated Le(a) (CA19-9), was evaluated immunohistochemically in 233 gastric biopsy specimens obtained at routine gastroscopy. Expression was also investigated in gastric tissues showing chronic gastritis, intestinal metaplasia, and carcinoma from 42 patients with gastric cancer. A polymerase chain reaction was performed for H. pylori and the bacterial babA2 gene. We identified type 1 precursor expression in 34.3%, type 1 H in 55.8%, Le(a) in 44.2%, Le(b) in 82.0%, Le(x) in 44.2%, Le(y) 56.7%, and CA19-9 in 16.3% of the 233 gastric biopsy specimens. Expression of type 1 H, Le(b), and CA19-9 was significantly associated with H. pylori infection and histological features (p < 0.05), and expression of type 1 H was an independent predictive factor for H. pylori infection by multivariate logistic regression (p = 0.020). Positivity for the babA2 genotype correlated significantly with H. pylori infection and type 1 H expression in gastric biopsy specimens (p < 0.05). The babA2 genotype was more frequent in gastric mucosa from the gastric cancer patients than in gastric biopsy specimens from routine gastroscopy (p = 0.009). In the 42 gastric cancer patients, the frequency of type 1 precursor, Le(a), and Le(x) expression was significantly higher in intestinal metaplasia and carcinoma than in chronic gastritis (p < 0.05), but the frequency of type 1 H and Le(b) expression was significantly lower in intestinal metaplasia and carcinoma (p < 0.05). In conclusion, Le expression, especially that of type 1 H, was significantly associated with clinicopathological features. In gastric cancer patients, Le expression was altered in intestinal metaplasia and carcinoma in comparison with chronic gastritis.     

An unusual double patella: a case report

Double patella following a 'sleeve fracture' in the lower pole of the patellar is rare and even more so after surgical treatment to the original injury. We report such a case in a boy injured at the age of 10, and presenting 3 years later with weakness and effusion. The management is described, including the technique of excision of the accessory patella and the lowering of the larger patella to a normal level. We believe that this is the first such case to be reported after surgical treatment of the primary fracture.     

Expression of type 1 and type 2 blood group-related antigens in normal and neoplastic gastric mucosa

The distribution of the blood group-related antigens type 1 (Lewis(a) [Le(a)], Lewis(b) [Le(b)]) and type 2 (H type 2, Y) has been examined in histologically normal and malignant mucosa of 40 surgical specimens of patients with adenocarcinoma of the stomach, with the use of a panel of monoclonal antibodies. Patients' Lewis phenotype and secretor status are correlated to the authors' findings. The surface epithelium of normal pyloric and fundic mucosa expressed the Lewis isoantigen (Le(a) in Le[a+b-] phenotype and Le(b) in Le[a-b+] phenotype), whereas the deep areas of this mucosa no showed the Le(a), Le(b) antigens and expressed the Y and H type 2 antigens whatever the secretor status of patients. Nineteen of 24 patients with Le(a-b+) phenotype showed anomalous expression of Lea antigen in neoplastic cells. In three of them, this alteration was found in tumor adjacent mucosa. No expression of Le(a) or Le(b) antigens was found in tumors or normal mucosa from Le(a-b-) phenotype patients.     

A technique for noninvasive respiratory gated radiation treatment system based on a real time 3D ultrasound image correlation: a phantom study

This paper proposes a new respiratory gated radiation treatment system that allows real-time tumor localization while avoiding invasive operation to a patient. The proposed system employs a three-dimensional (3D) ultrasound device, a 3D digital localizer, and a real-time image processing system. At the planning time, CT and 3D ultrasound reference data are simultaneously acquired under a breath-hold condition. At the treatment time, ultrasound data on three orthogonal planes are acquired and transferred to the image processing system on a real-time basis. Subsequently, normalized image correlation indices using the reference and the real-time ultrasound data are calculated for the three orthogonal planes after performing real-time coordinate transform using the 3D digital localizer attached to an ultrasound probe. Prior to the system execution, the coordinate transform matrices are partially calculated using an ultrasound calibration phantom and the 3D digital localizer. A trigger pulse to a linac can be generated when the normalized image correlation index exceeds a predetermined threshold level. Experiments have been carried out using a moving-target phantom that simulates a patient respiratory motion. We have observed that the variation of the calculated real-time correlation index synchronizes with the periodical motion of the moving-target, suggesting that real-time localization for a moving tumor is feasible with the proposed system.     

Application of ultrasound-tagged photons for measurement of amplitude of vibration of tissue caused by ultrasound: theory, simulation, and experiments

We investigate the modulation of an optical field caused by its interaction with an ultrasound beam in a tissue mimicking phantom. This modulation appears as a modulation in the intensity autocorrelation, which is measured by a photon counting correlator. The factors contributing to the modulation are: 1. amplitude of vibration of the particles of the tissue, 2. refractive index modulation, and 3. absorption coefficient in the region of the tissue intercepted by the ultrasound beam and light. We show in this work that a significant part of the contribution to this modulation comes from displacement of the tissue particles, which in turn is governed by the elastic properties of the tissue. We establish, both through simulations and experiments using an optical elastography phantom, the effects of the elasticity and absorption coefficient variations on the modulation of intensity autocorrelation. In the case where there is no absorption coefficient variation, we suggest that the depth of modulation can be calibrated to measure the displacement of tissue particles that, in turn, can be used to measure the tissue elasticity.     

Right hepatic artery crossing the common hepatic artery: an unusual blood supply to the liver

To perform hepatic surgery a precise preoperative and intraoperative study of liver vascular supply is mandatory. Detecting vascular variations may have great importance on surgical strategy and outcome, and details of anatomy do not concern only academical knowledge but become deeply involved in practice. We present a case of unusual blood supply to the liver, the common hepatic artery was directed to the right liver and a right hepatic artery originating from the superior mesenteric artery was directed to the left liver. The right hepatic artery crossed the common hepatic artery in the proximal part of the hepatic pedicle, anterior to the portal vein. To our knowledge this type of anatomical variation has not been described before and it represents a rare finding that has to be kept in mind, especially in case of major hepatectomies and more demanding splitting liver procedures such as A.L.P.P.S., in situ split, ex situ split and living donor liver transplantation.     

Prenatal diagnosis of short rib (polydactyly) syndrome with situs inversus.

We present a case of short rib (polydactyly) syndrome in which the diagnosis was made prenatally by ultrasound examination. The more specific diagnosis of short rib (polydactyly) syndrome type III was made on the basis of findings on radiographs obtained at birth. The sonographic and radiographic features are discussed. The patient had complete situs inversus and hypospadias. The former was reported in one other case of type III and the later has not been previously reported in this entity.     

Ciliated hepatic foregut cyst: a rare but increasingly reported liver cyst

We report a case of a ciliated hepatic foregut cyst (CHFC) in the left lobe of the liver in a 42-year-old woman. To date, only 60 cases of these respiratory epithelial lined hepatic cysts have been reported since first described by Friedrich in 1857. CHFC are believed to be congenitally derived from the embryonic foregut and are considered benign lesions that are most often unilocular. Recently, however, there has been documented malignant transformation in these cysts. The majority of patients with a CHFC are asymptomatic and the cyst is usually an incidental finding during abdominal imaging studies or during surgical exploration. Interestingly, 85% of the total number of cases of CHFC have been reported within the last two decades. This recent rise in case reports is likely explained by greater detection because of the dramatic rise in the use of abdominal imaging. In our case, however, ultrasound failed to demonstrate any lesion within the liver and on computed tomography the cyst was more consistent with a soft tissue mass. Therefore, pathologic evaluation was necessary for the correct diagnosis of this liver lesion and to exclude malignancy.     

Limited role of lipopolysaccharide Lewis antigens in adherence of Helicobacter pylori to the human gastric epithelium

In vitro and in vivo studies from various groups have suggested that Helicobacter pylori lipopolysaccharide (LPS) Lewis x (Le(x)) antigens mediate bacterial adhesion. We have now reevaluated this hypothesis by studying the adherence in situ of H. pylori strain 11637 and its corresponding Le(x)-negative rfbM mutant to human gastric mucosa from patients (n = 22) with various gastric pathologies. Significant binding of the parent strain was observed in only 8 out of 22 sections; in four out of eight patients, the Le(x)-negative mutant bound less well. One of these four patients displayed no gastric abnormalities, and the other three showed dysplasia, metaplasia, and adenocarcinoma, respectively; hence, we are unable to define the circumstances under which LPS-mediated adhesion takes place. We conclude that H. pylori LPS plays a distinct but minor role in adhesion.     

Uterine hemorrhage in a menopausal female associated with an arteriovenous malformation and myometritis

A case is described of vaginal bleeding in a 67-year-old female as the first manifestation of a uterine arteriovenous malformation (AVM). Although bleeding is the commonest presentation of an AVM, this is the first case known to have been precipitated by florid myometritis associated with the long-standing presence of an intra-uterine contraceptive device (IUCD). Uterine imaging studies utilising ultrasound scan with color Doppler were instrumental in suggesting the source of bleeding in this case. Subsequently, the patient suffered a torrential hemorrhage which necessitated hysterectomy.     

Noninvasive temperature estimation based on the energy of backscattered ultrasound

Hyperthermia has been used as a cancer treatment in which tumors are elevated to cytotoxic temperatures to aid in their control. A noninvasive method for volumetrically determining temperature distribution during treatment would greatly enhance the ability to uniformly heat tumors at therapeutic levels. Ultrasound is an attractive modality for this purpose. We investigated changes in backscattered energy (CBE) from pulsed ultrasound with temperature. Our predicted changes in backscattered energy were matched by in vitro measurements in samples of bovine liver, turkey breast, and pork rib muscle. We studied CBE in tissue regions with multiple scatterers, of isolated individual scatterers, and in collections of individual scatterers. The latter appears to have the most potential. We measured the CBE with a focused circular transducer with a center frequency of 7.5 MHz. The standard deviation of the CBE of 75-125 scattering regions from 0.3 to 0.5 cm3 volumes increased nearly monotonically from 37 degrees C to 50 degrees C in each tissue type. Although the slopes were different, the curve for each type of tissue was well matched by a second-degree polynomial, with a correlation coefficient of 0.99 in each case. Thus the use of the CBE of ultrasound for temperature estimation may have clinical promise with a convenient, low cost modality. Because our approach exploits the inhomogeneities present in tissue, we believe that if it is successful in vitro, it holds promise for in vivo application.