Identification of new partner chromosomes involved in fusions with the ETV6 (TEL) gene in hematologic malignancies

Several partner genes on different chromosomes have been reported to be fused with the ETV6 gene (located in chromosome band 12p13), with different breakpoints and different frequencies, in various hematologic malignancies, particularly acute myeloid and lymphoid leukemias and myelodysplastic syndromes. By using FISH and molecular analyses, we have analyzed five different pediatric and adult patients carrying cytogenetic abnormalities involving 12p13. Our findings demonstrate that ETV6 was rearranged in all the cases analyzed. In particular, ETV6 was disrupted by translocations with chromosomal bands 7q22, 7q36, 9q11, and 13q12, not previously described as partners of ETV6 in translocations, thus extending its promiscuity in rearranging with different partner genes. Genes Chromosomes Cancer 21:223–229, 1998. © 1998 Wiley-Liss, Inc.     

Ostial renal artery stent placement for atherosclerotic renal artery stenosis in patients with coronary artery disease

To test the utility of endoprosthetic treatment for ostial renal artery stenosis, and to examine blood pressure and its treatment, serum creatinine, and restenosis rate, 44 ostial renal stent placements were performed in 30 patients with concomitant coronary artery disease, arterial hypertension, and the indication for angiotensin converting enzyme (ACE) therapy. There was a marked decrease in systolic and diastolic blood pressure (163 ± 30 to 145 ± 17 and 93 ± 18 to 83 ± 10 mm Hg; P < 0.008) with a decrease in number of medication (3.2 ± 0.9 to 2.8 ± 1.0; P = 0.005). In 5 out of 8 patients not receiving an ACE inhibitor, this drug could be added. Serum creatinine changed from 1.46 ± 0.7 mg/dl to 1.39 ± 0.58 mg/dl (P = ns). Three patients showed restenosis (12.5%). Ostial stenting lowers blood pressure, decreases antihypertensive drugs and increases medication flexibility. Cathet. Cardiovasc. Diagn. 45:1–8, 1998. © 1998 Wiley-Liss, Inc.     

Short-rib–polydactyly syndrome type Verma-Naumoff–Le Marec in a fetus with histological hallmarks of type Saldino-Noonan but lacking internal organ abnormalities

Up to seven short-rib–polydactyly (SRP) syndromes have been identified so far with marked clinical and pathological overlap. We describe a 32-week-old, nonhydropic male fetus with thoracic “dysplasia,” short limbs, and unilateral postaxial polydactyly. All internal organs were normally developed, including the central nervous system. The external genitalia were unambiguously male, in accordance with a 46,XY karyotype. Radiological signs most closely resembled those of SRP, type Le Marec, though histology of the femoral physeal growth zone was consistent with the Saldino-Noonan type. The remarkable lack of visceral anomalies in conjunction with the radiological and histological findings further adds to the phenotypic spectrum of the SRP syndromes. The histological analysis in this case supports a close relationship between types Saldino-Noonan and Verma-Naumoff–Le Marec. Am. J. Med. Genet. 80:281–285, 1998. © 1998 Wiley-Liss, Inc.     

Comparison of outcomes in DeBakey type I versus DeBakey type II aortic dissection: a 17-year single center experience

BackgroundIt is controversial if the type or the size of aortic dissection is associated with the mortality in patients with acute aortic dissection (AAD) type I or type II according to DeBakey. Due to the pronounced aortic pathology in DeBakey type I compared to DeBakey type II, it is to be expected, that the DeBakey type I is associated with a significant higher morbidity and mortality. But we hypothesize that the current advances in surgical techniques, circulatory management, and postoperative care improve the clinical outcome of patients with DeBakey type I and II. The purpose of this study was to evaluate retrospectively the effect of these parameters on surgical outcome in patients with DeBakey type I and type II in a large cohort study.MethodsFrom 2001 to 2019, 395 consecutive patients (34.2% female) underwent surgical aortic repair at our institution. Patients were retrospectively classified into 2 groups: patients with type 1 dissection (group 1: n=309, median age of 62.0 years) and patients with type 2 dissection (group 2: n=86, 67.5 years). Survival was estimated by Kaplan-Meier estimator. Risk factors were analyzed by logistic regression analysis.ResultsThe patients in group 1 suffered significantly more often from coronary heart disease [43 (13.9%) vs. 20 (23.3%), P=0.036]. Otherwise, there were no significant differences between both groups concerning preoperative risk factors. The median surgical duration (279 vs. 263 min, P=0.026) and the circulatory arrest time (35 vs. 27 min, P<0.001) in group 1 were significantly higher. In a significantly higher number of patients in group 1, the aortic arch was completely replaced (18.4% vs. 1.2%, P<0.001) and a simultaneous coronary artery bypass grafting [18 (5.8%) vs. 11 (12.8%), P=0.028] was performed. The rate of re-thoracotomy [62 (20.1%) vs. 9 (10.5%), P=0.040], of postoperative delirium [66 (21.4%) vs. 9 (10.6%), P=0.024], and of tracheotomy [85 (27.5%) vs. 14 (16.3%), P=0.034] were significantly higher in group 1. Thirty-day mortality was 15.7% and did not differ significantly between both groups (P=0.867), as well as the long-term survival rates (P=0.956).ConclusionsDue to the pronounced aortic pathology in type I compared to type II, it is to be expected, that the type I is associated with a significant higher morbidity and mortality. DeBakey type I was an independent predictor for 30-day mortality in our study, however, based on our 17-year single center experience there was no difference between the long-term survival in both groups.     

Different types of pulmonary granuloma necrosis in immunocompetent vs. TNFRp55-gene-deficient mice aerogenically infected with highly virulent Mycobacterium avium

The immunopathogenesis of mycobacterial infections frequently involves the formation of caseating granulomas which cause tissue destruction and, in the case of tuberculosis (TB), may lead to cavity formation. Both intravenous and aerosol models of Mycobacterium tuberculosis infection in mice do not reflect the pulmonary lesions characteristic of TB patients. Using both low-dose (10² colony-forming units, cfu) and high-dose (10⁵ cfu) aerosol infection with a highly virulent strain of Mycobacterium avium (TMC724) in C57BL/6 mice, it is now shown that these mice are capable of developing centrally caseating necrosis in lung granulomas after approximately 4 months of infection. In contrast, mice infected intravenously with the high dose never developed this type of lesion, although bacterial counts in their lungs reached levels comparable to those attained by aerosol-infected mice (10¹⁰ cfu). To study the relevance of events signalled by tumour necrosis factor (TNF) in this model, TNFRp55 gene-deficient and syngeneic C57BL/6 immunocompetent mice were infected with 10⁵ cfu M. avium via aerosol. In gene-deficient mice, newly formed pulmonary granulomas acutely disintegrated, showing signs of apoptotic cell death and neutrophil influx, and TNFRp55 knock-out mice all succumbed to infection just beyond the stage of granuloma initiation. Aerogenic infection with M. avium in mice is a suitable model to study the immunopathogenesis of granuloma necrosis because it closely mimicks the histopathology of mycobacterial infections in humans, including TB. Furthermore, the use of TNFRp55 gene-deficient mice in this model establishes a role for TNF in maintaining the integrity of a developing pulmonary granuloma. Copyright © 1999 John Wiley & Sons, Ltd.     

Léri-Weill syndrome as part of a contiguous gene syndrome at Xp22.3

We report on a mother and her 5-year old son, both with a terminal deletion of the short arm of the X chromosome. By molecular genetic analysis the breakpoint was located distal to steroid sulfatase gene. The boy manifested, due to nullisomy of this region, short stature (SHOX), chondrodysplasia punctata (ARSE), and mental retardation (putative mental retardation gene MRX 49). Short stature is present in mother and son, but both also had bilateral Madelung deformity, a key finding in the Léri-Weill syndrome.We discuss the phenotype in relationship to hitherto published cases with chromosomal aberrations and contiguous gene syndromes of Xp22.3. Am. J. Med. Genet. 83:367–371, 1999. © 1999 Wiley-Liss, Inc.     

Innervation of VIP-immunoreactive neurons by the ventroposteromedial thalamic nucleus in the barrel cortex of the rat

We investigated the synaptic terminals of fibers originating in the ventroposteromedial thalamic nucleus (VPM) and projecting to the main input layers (IV/III) of the rat posteromedial barrel subfield. It was our aim to determine whether or not the subpopulation of vasoactive intestinal polypeptide (VIP)-immunoreactive neurons in these layers are directly innervated by the sensory thalamus. Anterograde tracing with Phaseolus vulgaris leucoagglutinin (PHA-L) and immunohistochemistry for VIP were combined for correlated light and electron microscopic examination. Columns of cortical tissue were well defined by barrel-like patches of PHA-L-labeled fibers and boutons in layers IV and III. Within these columns VIP-immunoreactive perikarya were located mainly in supragranular layers. Marked perikarya were also seen in infragranular layers, but their immunoreactivity was often weaker. Granular layer IV, which is the main terminal field for thalamic fibers, contained fewer VIP neurons than supragranular layers. In the light microscope, however, PHA-L-labeled fibers appeared to contact the somata or proximal dendrites of 60–86% of the layer IV VIP neurons. By contrast, only 18–35% of the VIP neurons in the supragranular layers, which receive a moderately dense projection from the VPM, appeared to be contacted. PHA-L-labeled boutons were seen close to 13–25% of infragranular VIP-positive cells. Electron microscopy showed that thalamic fibers formed at most four asymmetric synapses on a single layer IV, VIP-positive neuron. Although the proportion of VIP-positive neurons with labeled synapses was lower in supragranular layers, most of them shared multiple asymmetric synapses with labeled thalamic fibers. Up to six labeled synapses were seen on individual VIP neurons in layer III. We conclude that subpopulations of VIP-immunoreactive neurons, located in layers IV, III, and II are directly innervated by the VPM. These neurons may be involved in the initial stages of cortical processing of sensory information from the large, mystacial vibrissae. Since VIP is known to be colocalized with the inhibitory transmitter GABA, it is likely that VIP neurons participate in the shaping of the receptive fields in the barrel cortex. © 1996 Wiley-Liss, Inc.     

Electrical coupling among Bergmann glial cells and its modulation by glutamate receptor activation

We studied the characteristics of electrical coupling between Bergmann glial cells in mouse cerebellar slices using Lucifer Yellow injection, patch-clamping cell pairs, and ultrastructural inspection. While early postnatal cells (days 5–7) were not coupled, coupling was abundant at postnatal days 20–24. Coupled cells were arranged perpendicular to the parallel fibers in a parasagittal section, forming a string, rather than a cluster of cells. Electron microscopy revealed that gap junctions were abundant in the distal parts of the processes. Gap junctions between cell bodies and processes were very rare, and no gap junctions were found between cell bodies of adjacent Bergmann glial cells. The junctional conductance was voltage and time independent and could be markedly reduced by halothane. Alkalization of cells (by applying NH₄⁺ increased the junctional conductance to 150%, while acidification of the cell interior (by removing NH₄⁺) led to a decrease to 70%. Activation of AMPA receptors induced a blockade of the junctional conductance to 30% of the control. This link is most likely mediated by the influx of Ca²⁺ via the receptor since this effect was not observed in Ca²⁺-free medium, suggesting that Ca²⁺ entry via the kainate receptor pore led to the closure of gap junctions. These studies indicate that electrical coupling between Bergmann glial cells is not only developmentally regulated but also controlled by physiological stimuli. © 1996 Wiley-Liss, Inc.