[Critical assessment of a new endoscopic anatomic concept for the so-called cardia in the sense of the notions of Parmenides and Martin Heidegger]. / Kritische Betrachtung neuer Konzepte zur endoskopischen Anatomie des ösphagogastralen Übergangs im Sinne des Denkens von Parmenides und Martin Heidegger.

Current endoscopic anatomy interposes the gastric cardia between the tubular oesophagus and the proximal stomach. In contrast to that, recent evidence unfolds a different view. Using "PubMed" and "Scopus" searches, we examined if the novel understanding regarding the cardia goes in line with the concept of unfolding, as described by Heidegger based on the ancient didactic poetry of Parmenides. What has been taken as gastric cardia in fact represents reflux-damaged, dilated, columnar lined oesophagus (CLO): dilated distal oesophagus (DDO). Due to its macroscopic gastric appearance it cannot be discriminated from the stomach by endoscopy. Differentiation between DDE and proximal stomach requires the histopathology of measured multi-level biopsies obtained from the DDO and the proximal stomach. Cardaic, onxytocardiac mucosa and intestinal metaplasia (IM; Barrett's oesophagus) define CLO and thus the oesophageal location, while oxyntic mucosa (OM) of the proximal stomach verifies a gastric biopsy location. Endoscopically visible CLO and DDO define the morphological manifestation of reflux: the squamo-oxyntic gap (SOG). Biopsies obtained from the level of the diaphragmatic impressions allow differentiation between an enlarged hiatus with normal anatomic content (CLO; oesophagus) vs. hernia with abnormal content (OM; stomach). Non-dysplastic Barrett's oesophagus exists in 10 %-17 % of asymptomatic and in 20 %-100 % (with increasing CLO length) of reflux symptom-positive individuals (annual cancer risk: 0.2 %-0.7 %). These data justify biopsy of an endoscopically normal appearing squamocolumnar junction for the exclusion of Barrett's oesophagus and cancer risk. In the absence of contraindications, cancer risk-based therapy of dysplastic Barrett's oesophagus includes radiofrequency ablation (RFA) ± endoscopic resection. The perception of the cardia as reflux damaged DDO mirrors the concept of unfolding, as described by the interpretation of the didactic poem of Parmenides by Heidegger. Our data recommend to omit the term "cardia" and allocate morphology either to the oesophagus (CLO, DDO) or to the proximal stomach or indicate that allocation is impossible (i. e.. tumour-induced). Future studies will have to test the value of this novel concept for diagnosis, treatment of gastro-oesophageal reflux disease and cancer prevention.

The distribution of KIR-HLA functional blocks is different from north to south of Italy.

The killer cell immunoglobulin-like receptor (KIR)-human leukocyte antigen (HLA) interaction represents an example of genetic epistasis, where the concomitant presence of specific genes or alleles encoding receptor-ligand units is necessary for the activity of natural killer (NK) cells. Although KIR and HLA genes segregate independently, they co-evolved under environmental pressures to maintain particular KIR-HLA functional blocks for species survival. We investigated, in 270 Italian healthy individuals, the distribution of KIR and HLA polymorphisms in three climatic areas (from cold north to warm south), to verify their possible geographical stratification. We analyzed the presence of 13 KIR genes and genotyped KIR ligands belonging to HLA class I: HLA-C, HLA-B and HLA-A. We did not observe any genetic stratification for KIR genes and HLA-C ligands in Italy. By contrast, in a north-to-south direction, we found a decreasing trend for the HLA-A3 and HLA-A11 ligands (P = 0.012) and an increasing trend for the HLA-B ligands carrying the Bw4 epitope (P = 0.0003) and the Bw4 Ile80 epitope (P = 0.0005). The HLA-A and HLA-B KIR ligands were in negative linkage disequilibrium (correlation coefficient -0.1211), possibly as a consequence of their similar function in inhibiting NK cells. The distribution of the KIR-HLA functional blocks was different along Italy, as we observed a north-to-south ascending trend for KIR3DL1, when coupled with HLA-B Bw4 ligands (P = 0.0067) and with HLA-B Bw4 Ile80 (P = 0.0027), and a descending trend for KIR3DL2 when coupled with HLA-A3 and HLA-A11 ligands (P = 0.0044). Overall, people from South Italy preferentially use the KIR3DL1-HLA-B Bw4 functional unit, while those from the North Italy equally use both the KIR3DL2-HLA-A3/A11 and the KIR3DL1-HLA-B Bw4 functional units to fight infections. Thus, only KIR3DL receptors, which exert the unique role of microbial sensors through the specific D0 domain, and their cognate HLA-A and HLA-B ligands are selectively pressured in Italy according to geographical north-to-south distribution.

Description of the novel HLA-DPB1*137:01 allele found in an Italian subject.

In this report, we describe the identification and sequencing of a novel HLA-DPB1 allele, found in an Italian haematological patient. This allele is identical to DPB1*17:01 except for a single nucleotide substitution (GAC→GAG) at position 57, which changes the encoded amino acid from Asp to Glu.

Characterization of a novel HLA-DQB1*06 allele, HLA-DQB1*06:04:04.

The novel allele human leukocyte antigen(HLA)-DQB1*06:04:04 differs from HLA-DQB1*06:04:01 by a silent nucleotide substitution at codon 75 (TTG → CTG).

Killer immunoglobulin-like receptors (KIR) and their HLA-ligands in Italian paroxysmal nocturnal haemoglobinuria (PNH) patients.

Paroxysmal nocturnal haemoglobinuria (PNH) is a haematopoietic disorder characterized by expansion of phosphatidylinositol glycan-A-defective progenitor(s). Immune-dependent mechanisms, likely involving a deranged T cell-dependent autoimmune response, have been consistently associated with the selection/dominance of PNH precursors. Natural killer (NK) lymphocytes might participate in PNH pathogenesis, but their role is still controversial. NK activity is dependent on the balance between activating and inhibiting signals. Key component in such regulatory network is represented by killer immunoglobulin-like receptors (KIR). KIR are also involved in the regulation of adaptive cytotoxic T cell response and associated with autoimmunity. This study investigated on the frequency of KIR genes and their known human leukocyte antigen (HLA) ligands in 53 PNH Italian patients. We observed increased frequency of genotypes characterized by ≤2 activating KIR as well as by the presence of an inhibitory/activating gene ratio ≥3.5. In addition, an increased matching between KIR-3DL1 and its ligand HLA-Bw4 was found. These genotypes might be associated with lower NK-dependent recognition of stress-related self molecules; this is conceivable with the hypothesis that an increased availability of specific T cell targets, not cleared by NK cells, could be involved in PNH pathogenesis. These data may provide new insights into autoimmune PNH pathogenesis.

Is there a role for dynamic swallowing MRI in the assessment of gastroesophageal reflux disease and oesophageal motility disorders?

OBJECTIVES: To evaluate the diagnostic value of dynamic MRI swallowing in patients with symptoms of Gastroesophageal Reflux Disease (GERD). METHODS: Thirty-seven patients (17 m/20f) with typical signs of GERD underwent MR swallowing in the supine position at 1.5 T with a phased-array body coil. Using dynamic, gradient echo sequences (B-FFE) in the coronal, sagittal and axial planes, the bolus passages of buttermilk spiked with gadolinium chelate were tracked. MRI, pH-metry and manometry were performed within 31 days and results were compared. RESULTS: MRI results were concordant with pH-metry in 82% (23/28) of patients diagnosed with abnormal oesophageal acid exposure by pH-metry. Five patients demonstrated typical symptoms of GERD and had positive findings with pH monitoring, but false negative results with MRI. In four of six patients (67%), there was a correct diagnosis of oesophageal motility disorder, according to manometric criteria, on dynamic MRI. The overall accuracy of MRI diagnoses was 79% (27/34). A statistically significant difference was found between the size of hiatal hernia, grade of reflux in MRI, and abnormal acid exposure on pH-monitoring. CONCLUSIONS: MR fluoroscopy may be a promising radiation-free tool in assessing the functionality and morphology of the GE junction. KEY POINTS: • Swallowing MRI can assess anatomy and function of the gastroesophageal-junction • Swallowing MRI can help identifying reflux and motility disorders • Definition of the size of hiatal hernias is possible in all three planes in MR. • Short duration of swallowing MRI enables its application in routine clinical practice.

Sequence of a novel HLA-B*51 allele in a volunteer haematopoietic stem cell donor.

We describe a novel HLA-B*51 allele detected by DNA direct sequencing. The sequence of this allele has been officially named B*51:78 as a confirmatory sequence. This new allele nucleotide sequence differs from HLA-B*51:01:01 for two point mutations in exon 2 where codons 79-80 change from CGG-ATC to CGC-ACC (p.Ile80Thr).

A discrepancy between serological and molecular typing results led to identification of a novel HLA-B*57 allele: HLA-B*5728N.

Summary Here, we describe the characterisation of a new allelic variant of HLA-B*57. The novel allele, HLA-B*5728N, was identified with sequence-based typing in a Caucasoid family. HLA-B*5728N, differs from HLA-B*5701 because of a nucleotide substitution at position 420 (C->G) resulting in a coding change from Tyrosine to a stop codon.

Thymoma-associated immunodeficiency: a syndrome characterized by severe alterations in NK, T and B-cells and progressive increase in naïve CD8+ T Cells.

Thymomas are rare tumours that sustain T-lymphopoiesis and trigger a variety of autoimmune diseases and immunodeficiencies, including a fatal hypogammaglobulinemia, namely Goods Syndrome (GS). Due to its rarity, GS has been poorly investigated and immunological features, as well as pathogenetic mechanisms underlying this syndrome, are unclear. We studied 30 thymoma patients by performing an immunological assessment, including immunophenotype and analysis of T cell repertoire (TCR). Development of GS was characterized by a progressive decrease in B, CD4 T and NK lymphocytes. These alterations paired with accumulation of CD8+CD45RA+ T cells that showed a polyclonal repertoire without expansions of specific clonotypes. GS is defined as hypogammaglobulinemia with thymoma. Here, we show for the first time that this syndrome is characterized by a severe loss of CD4+, NK and B cells. Furthermore, the accumulation of CD8+CD45RA+ T lymphocytes parallels these changes; this accumulation may have a role in determining the disease and can be used to monitor clinical stages of immunodeficiency in thymoma.

Dynamic MR imaging of the gastroesophageal junction in healthy volunteers during bolus passage.

PURPOSE: To evaluate the feasibility of noninvasive dynamic fast magnetic resonance imaging (MRI) during swallowing in healthy volunteers, and to determine esophageal function at the gastroesophageal junction during swallowing. MATERIALS AND METHODS: A total of 20 healthy volunteers underwent MRI while swallowing in the supine position. Dynamic gradient-echo (GRE) sequences (balanced fast field echo [B-FFE]) were employed in three planes on a 1.5T unit using a phased-array body coil. Buttermilk spiked with gadolinium (Gd) chelate (40:1) for bolus passage was used as an oral contrast agent. We evaluated visualization of esophageal bolus transit, bolus transit time (BTT), peristalsis, identification of the gastroesophageal junction, and reflux during the Valsalva maneuver. RESULTS: The mean visible length of the esophagus was 16.2+/-5.3 cm in the sagittal view, and 13.8+/-4.9 cm in the coronal view. In the sagittal view the BTT was defined in 15 of 20 volunteers and was 7.6+/-1.4 seconds. The BTT in the coronal view was measured in seven of 20 volunteers and was 8+/-1.3 seconds on average. The axial view yielded higher scores (2.25) than the coronal (1.98) and sagittal (1.78) views for identification of the cardia and during the Valsalva maneuver. Bolus contrast was better displayed in the sagittal (2.2) view than in the coronal (2.08) or axial (1.73) planes. In six volunteers, gastroesophageal abnormalities, such as axial hernia, reflux, and nonperistaltic contractions, were identified. For statistical analysis we used the Friedman test and a one-way analysis of variance (ANOVA). CONCLUSION: The results indicate that dynamic MR swallowing is a feasible and reproducible technique that warrants further studies in patients.

Distribution of killer cell immunoglobulin-like receptors genes in the Italian Caucasian population.

BACKGROUND: Killer cell immunoglobulin-like receptors (KIRs) are a family of inhibitory and activatory receptors that are expressed by most natural killer (NK) cells. The KIR gene family is polymorphic: genomic diversity is achieved through differences in gene content and allelic polymorphism. The number of KIR loci has been reported to vary among individuals, resulting in different KIR haplotypes. In this study we report the genotypic structure of KIRs in 217 unrelated healthy Italian individuals from 22 immunogenetics laboratories, located in the northern, central and southern regions of Italy. METHODS: Two hundred and seventeen DNA samples were studied by a low resolution PCR-SSP kit designed to identify all KIR genes. RESULTS: All 17 KIR genes were observed in the population with different frequencies than other Caucasian and non-Caucasian populations; framework genes KIR3DL3, KIR3DP1, KIR2DL4 and KIR3DL2 were present in all individuals. Sixty-five different profiles were found in this Italian population study. Haplotype A remains the most prevalent and genotype 1, with a frequency of 28.5%, is the most commonly observed in the Italian population. CONCLUSION: The Italian Caucasian population shows polymorphism of the KIR gene family like other Caucasian and non-Caucasian populations. Although 64 genotypes have been observed, genotype 1 remains the most frequent as already observed in other populations. Such knowledge of the KIR gene distribution in populations is very useful in the study of associations with diseases and in selection of donors for haploidentical bone marrow transplantation.

Allogeneic bone marrow transplantation restores IGF-I production and linear growth in a gamma-SCID patient with abnormal growth hormone receptor signaling.

Severe combined immunodeficiency (SCID) is a heterogeneous group of disorders characterized by a severe defect of both T- and B-cell immunity, which generally require allogeneic bone marrow transplantation (BMT) within the first years of life. We previously reported a patient affected with an X-linked SCID due to L183S hemizygous missense gamma chain mutation, whose severe short stature was due to a peripheral growth hormone (GH) hyporesponsiveness associated to abnormal GH receptor (GH-R) signal transduction. In this study, we report the effect of BMT on the GH-R/insulin-like growth factor I (IGF-I) axis. After BMT, the patient showed a significant improvement in linear growth and normalization of basal- and GH-stimulated IGF-I values, which paralleled a fully competent immunological reconstitution. This suggests that cells derived from the hematopoietic stem cell may exert an unexpectedly significant role in producing IGF-I. This may also suggest that stem cell-based therapies may be useful for the correction of non-hematopoietic inherited disorders, such as those of GH-R/IGF-I axis.

The differentiation inducers phenylacetate and phenylbutyrate modulate camptothecin sensitivity in colon carcinoma cells in vitro by intracellular acidification.

Aromatic fatty acids such as phenylbutyrate (PB) and its metabolite phenylacetate (PA) induce growth arrest, differentiation and apoptosis in solid tumor cells. Despite their antiproliferative action they were reported to exhibit a synergistic effect in combination with cytotoxic drugs like topotecan, and others. Since the activity of the camptothecines (CPTs) depends on local pH conditions, we investigated, whether PB/PA modulate CPT effects indirectly by affecting intracellular pH in SW620 and SW480 colon cancer cells. The results for the colon carcinoma cells show an antagonistic interaction for the combination of CPT and 0.25-5 mM PA in viability assays, resulting in an approximately 3-fold increase in IC50 (control: 20+/-7 nM). A synergistic effect with significantly increased numbers of late apoptotic/necrotic cancer cells (difference +21+/-4%) and 1.4-fold sensitization were detected upon inclusion of 2.5 mM PA during a 4-h CPT (10 micro;M) loading phase. In response to 0.25-1 mM PA/PB the cells exhibit a reversible decrease of pHi (0.1-0.31 pH units) in HEPES- or bicarbonate-buffered media. Dose-dependent acidification and pHi-recovery occurred following addition of PA and PB after an acid load and inhibition of the Na+/H+-antiporter and bicarbonate exchangers, pointing to a possible intracellular mechanism of cytoplasmic acidification. It is concluded that the synergistic modulation of CPT toxicity by short-term PA/PB treatment in colon carcinoma cells is caused by changes in intracellular pH, possibly affecting quantity and localization of the active closed lactone form of this drug.

[Inguinal hernia as a diagnostic error in ruptured groin aneurysm]. / Inguinalhernie als Fehldiagnose bei rupturiertem Leistenaneurysma.

Anastomotic aneurysms observed with an incidence of 0.5% to 5.0% are considered a known complication following arterial surgery, especially when fabric grafts in the inguinal region are implanted. An anecdotal report is presented describing a 64-year old male patient, who developed, 10 years following an autologous femoro-tibial vein graft, a huge mass in the left groin. The lesion was considered an incarcerated inguinal hernia and the patient was admitted to the Department of Surgery for emergency repair. Clinical examination, duplexsonography and CT scan clarified the diagnosis of an aneurysm with a diameter of 13 cm. The aneurysm was resected, and a femoro-profundal vein graft was implanted orthotopically, the graft was covered with a sartorius muscle flap. The postoperative course was uneventful. The diagnosis is suspected by clinical examination and usually confirmed by duplexsonography. The exact etiology of suture line aneurysms is unknown; in the present case progression of the underlying arteriosclerotic arterial disease after a follow up of 10 years is likely. For the treatment the usual methods of complicated aneurysm repair and preservation of the arterial circulation--using autologous in situ methods or extraanatomic bypass grafts--with additional biologic coverage are at hand.

Defective surface expression of attractin on T cells in patients with common variable immunodeficiency (CVID).

The proliferative responses of T lymphocytes of a subset of patients with CVID are abnormally low. This may be due to abnormalities in extracellular interactions or signalling defects downstream from membrane-associated receptors. Demonstrating that the T cell receptor signalling was normal, we observed no abnormal pattern of activation-induced tyrosine phosphorylation in cells from CVID patients. Moreover, the addition of exogenous IL-2 increased the low proliferation to mitogens, thus indicating the integrity of the IL-2R signalling apparatus. Attractin is a rapidly expressed T cell activation antigen involved in forming an association between T cells and monocytes. Twenty-four to 48 h after activation by CD3 cross-linking, attractin expression was not up-regulated on the cells of CVID patients despite normal up-regulation of CD25 and CD26. On control cells, however, attractin expression was up-regulated together with CD25 and CD26. The addition of the purified 175-kD attractin was capable of restoring the proliferative response of peripheral blood mononuclear cells following CD3 X-L in the presence of suboptimal concentrations of rIL-2 (10 and 20 U/ml). The effect was dose-dependent with the maximal effect at a concentration of 500 ng/ml, and present at a concentration as low as 50 ng/ml. Due to the likely role of attractin in cell guidance and amplification of the immune response, our results indicate that the lack of up-regulation of the molecule in patients with CVID may in turn affect any further step of productive immune response. Our finding may also imply a potential therapeutic role for this novel molecule.

Brain migration disorder and T-cell activation deficiency associated with abnormal signaling through TCR/CD3 complex and hyperactivity of Fyn tyrosine kinase.

In this study we report on a patient affected by a brain migration disorder and a T-cell activation deficiency presumably inherited as an autosomal recessive trait. The immunological evaluation revealed that the mitogen stimulation failed to induce a proper up-regulation of membrane expression of T-cell activation markers, and cell proliferation. This functional impairment was associated with abnormalities of the signal transduction process that follows T-cell receptor stimulation. A constitutive hyperphosphorylation of the Fyn tyrosine kinase was documented. This is the first report on a T-cell signaling abnormality associated with a developmental brain disorder. Whether the alteration of Fyn, which plays a role in both neurological and immunological systems, is responsible for either disorder remains to be elucidated.

Effects of substance P on human colonic mucosa in vitro.

Previous studies indicated that the peptide substance P (SP) causes Cl--dependent secretion in animal colonic mucosa. We investigated the effects of SP in human colonic mucosa mounted in Ussing chamber. Drugs for pharmacological characterization of SP-induced responses were applied 30 min before SP. Serosal, but not luminal, administration of SP (10(-8) to 10(-6) M) induced a rapid, monophasic concentration and Cl--dependent, bumetanide-sensitive short-circuit current (Isc) increase, which was inhibited by the SP neurokinin 1 (NK1)-receptor antagonist CP-96345, the neuronal blocker TTX, the mast cell stabilizer lodoxamide, the histamine 1-receptor antagonist pyrilamine, and the PG synthesis inhibitor indomethacin. SP caused TTX- and lodoxamide-sensitive histamine release from colonic mucosa. Two-photon microscopy revealed NK1 (SP)-receptor immunoreactivity on nerve cells. The tyrosine kinase inhibitor genistein concentration dependently blocked SP-induced Isc increase without impairing forskolin- and carbachol-mediated Isc increase. We conclude that SP stimulates Cl--dependent secretion in human colon by a pathway(s) involving mucosal nerves, mast cells, and the mast cell product histamine. Our results also indicate that tyrosine kinases may be involved in this SP-induced response.

Bacteroides fragilis toxin 2 damages human colonic mucosa in vitro.

BACKGROUND: Strains of Bacteroides fragilis producing a 20 kDa protein toxin (B fragilis toxin (BFT) or fragilysin) are associated with diarrhoea in animals and humans. Although in vitro results indicate that BFT damages intestinal epithelial cells in culture, the effects of BFT on native human colon are not known. AIMS: To examine the electrophysiological and morphological effects of purified BFT-2 on human colonic mucosa in vitro. METHODS: For resistance (R) measurements, colonic mucosa mounted in Ussing chambers was exposed to luminal or serosal BFT-2 (1.25-10 nM) and after four hours morphological damage was measured on haematoxylin and eosin stained sections using morphometry. F actin distribution was assessed using confocal microscopy. RESULTS: Serosal BFT-2 for four hours was four-, two-, seven-, and threefold more potent than luminal BFT-2 in decreasing resistance, increasing epithelial 3H-mannitol permeability, and damaging crypt and surface colonocytes, respectively (p<0.05). Confocal microscopy showed reduced colonocyte F actin staining intensity after exposure to BFT-2. CONCLUSIONS: BFT-2 increases human colonic permeability and damages human colonic epithelial cells in vitro. These effects may be important in the development of diarrhoea and intestinal inflammation caused by B fragilis in vivo.