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91.
92.

Purpose

The aim of this study is to present the anatomical data about intrahepatic venous anastomoses found in normal human livers. The focus is on the middle hepatic vein (MHV) anastomoses, because their existence or non-existence could be of crucial importance in tumour resections as well as in split or living donor liver transplantations.

Materials and methods

The frequency of livers with intrahepatic venous anastomoses was determined on 164 corrosion casts and the diameter of each anastomosis was measured. Additionally, the type of connection and the position within the liver (liver segment) was determined for each MHV anastomosis.

Results

Intrahepatic venous anastomoses were found in 46 % (75/164), whereas MHV anastomoses were found in 28 % (44/164) of liver casts. Most commonly (39/44), MHV had anastomotic connections with the right hepatic vein (RHV), and also with the inferior RHV, the left hepatic vein and the short subhepatic vein. In more than three quarters of liver casts, MHV–RHV anastomoses were found in liver segment 8; in 45 % of cases, there was more than one anastomosis in this liver segment. The diameter of MHV–RHV anastomoses found in segment 8 was ≥1 mm in 90.6 % of cases.

Conclusion

As MHV anastomoses were present in more than a quarter of all examined liver casts, we believe that detailed anatomical data presented in this article, together with up to date radiologic technics which enable even 3D reconstruction of venous anastomoses in the liver, could contribute to the clinician’s decisions when planning surgical procedures.  相似文献   
93.
The surveillance of vectors for arthropod-borne pathogens is nowadays an important tool in surveillance programmes throughout Europe. Whereas many studies have been performed to screen arthropods for viruses or bacterial pathogens, only limited information is available concerning the geographical distribution and vector range of pathogenic filariae in Central Europe. To consider the prevalence of filarial parasites in mosquito vectors, we performed a molecular survey of mosquitoes for filarial DNA. Mosquito collection was conducted at six study sites in the South Moravian region (Czech Republic) close to the borders with Slovakia and Austria from 2009 to 2011. Molecular screening of mosquitoes was conducted using conventional PCR with primers designed to amplify the mitochondrial cytochromoxidase subunit I gene as well as the partial 5.8S ribosomal RNA gene. A total of 13,222 mosquitoes belonging to six species were captured and distributed into 237 pools with different numbers of individuals. Overall, four pools were positive for Dirofilaria repens (a minimum infection rate 0.03 %) at two study sites (both natural and urban). Another filarial parasite detected during a study into Aedes vexans mosquitoes revealed the closest homology to Setaria spp. We detected specific D. repens DNA in Ae. vexans mosquitoes for the first time in the Czech Republic and confirmed the circulation of Dirofilaria spp. in a natural focus of infection providing an epidemiological link between autochthonous canine cases and mosquito vectors in the area studied.  相似文献   
94.
Peeling skin disease (PSD) is an autosomal recessive skin disorder caused by mutations in CDSN and is characterized by superficial peeling of the upper epidermis. Corneodesmosin (CDSN) is a major component of corneodesmosomes that plays an important role in maintaining epidermis integrity. Herein, we report a patient with PSD caused by a novel homozygous large deletion in the 6p21.3 region encompassing the CDSN gene, which abrogates CDSN expression. Several genes including C6orf15, PSORS1C1, PSORS1C2, CCHCR1, and TCF19 were also deleted, however, the patient showed only clinical features typical of PSD. The deletion size was 59.1 kb. Analysis of the sequence surrounding the breakpoint showed that both telomeric and centromeric breakpoints existed within Alu‐S sequences that were oriented in opposite directions. These results suggest an Alu‐mediated recombination event as the mechanism underlying the deletion in our patient.  相似文献   
95.
The interruption of supraspinal input to the spinal cord leads to motor dysfunction and the development of spasticity. Clinical studies have shown that Baclofen (a GABAB agonist), while effective in modulating spasticity is associated with side-effects and the development of tolerance. The aim of the present study was to assess if discontinued Baclofen treatment and its repeated application leads antispasticity effects, and whether such changes affect neuronal nitric oxide synthase (nNOS) in the brainstem, nNOS and parvalbumin (PV) in lumbar α-motoneurons and glial fibrillary acidic protein in the ventral horn of the spinal cord. Adult male Wistar rats were exposed to Th9 spinal cord transection. Baclofen (30 mg/b.w.) diluted in drinking water, was administered for 6 days, starting at week 1 after injury and then repeated till week 4 after injury. The behavior of the animals was tested (tail-flick test, BBB locomotor score) from 1 to 8 weeks. Our results clearly indicate the role of nitric oxide, produced by nNOS in the initiation and the maintenance of spasticity states 1, 6 and 8 weeks after spinal trauma. A considerable decrease of nNOS staining after Baclofen treatment correlates with improvement of motor dysfunction. The findings also show that parvalbumin and astrocytes participate in the regulation of ion concentrations in the sub-acute phase after the injury.  相似文献   
96.

Introduction

Acute coronary syndrome (ACS) is caused by destabilization and rupture of atherosclerotic plaque in the coronary artery via mechanisms affecting leukocyte signaling, rolling, adhesion, extravasation and inflammation-promoting factors. The majority of cellular communication takes place on the membrane surface that is covered with glycoproteins and glycolipids synthesized by glycosyltransferases. The aim of this study was to determine the mRNA expression of leukocyte adhesion-related glycosyltransferases in patients during the onset and the chronic phase of ACS and to compare the expression with matching subjects without coronary disease.

Subjects and methods

The study included 26 ACS patients and 26 ACS-free matched-pair controls. Blood samples were collected at the time of hospital admittance and 8 days later. Expression analysis of six fucosyltransferases and six sialyltransferases was performed by a real-time polymerase chain reaction.

Results

At the time of admittance ACS subjects had lower expression levels of FUT4, ST6GalNac4, ST6Gal1 and GM3 synthase (p < 0.05) than the control subjects, and moreover, after 8 days down-regulation of FUT7 and ST6GalNac3 was also observed (p < 0.05). When compared to the initial gene expression, after treatment and stabilization of ACS subjects, FUT7, ST6GalNac2 and ST6GalNac3 were down-regulated, whereas ST6GalNac1 was up-regulated. Expression levels of FUT7, ST6GalNac1, ST6GalNac2 and ST6GalNac3 were predicted by several drugs and medical history.

Conclusion

Expression of glycosyltransferase genes differs in ACS and control subjects. During the course of the ACS study we established further changes in gene expression levels. Medical history was predictive of gene expression levels while drugs were shown to modulate expression levels.  相似文献   
97.
The most frequent chromosomal aberrations with the well established prognostic meaning in chronic lymphocytic leukemia (CLL) are +12, del(11q), del(13q), and del(17p). Less common translocations lead to deregulation of genes primarily due to juxtaposition with IGH gene.

We present a case of CLL patient with atypical morphology and an aggressive course of disease. In spite of aggressive treatment including allogeneic hematopoietic stem cell transplantation disease progressed into a rare cutaneous Richter's syndrome. Trisomy 12 was found as a sole chromosomal change at initial cytogenetic analysis of lymphoma cells. At progression, besides trisomy 12 three concomitant balanced translocations t(2;14)(p13;q32), t(14;19)(q32;q13), and t(18;22)(q21;q11) were found. The same karyotype was confirmed in cells aspirated from skin infiltrates at Richter transformation.

Atypical cytological features, trisomy 12, and a progressive course of disease observed in our case are typical for CLL with each of particular Ig translocations that were concomitantly found in CLL for the first time. Similar to “double hit” lymphoma concurrent rearrangements may be relevant also in CLL.  相似文献   

98.
Protein misfolding has been proposed to be a common pathogenic mechanism in many inborn errors of metabolism including cystathionine β-synthase (CBS) deficiency. In this work, we describe the structural properties of nine CBS mutants that represent a common molecular pathology in the CBS gene. Using thermolysin in two proteolytic techniques, we examined conformation of these mutants directly in crude cell extracts after expression in E. coli. Proteolysis with thermolysin under native conditions appeared to be a useful technique even for very unstable mutant proteins, whereas pulse proteolysis in a urea gradient had limited values for the study of the majority of CBS mutants due to their instability. Mutants in the active core had either slightly increased unfolding (p.A114V, p.E302K and p.G307S) or extensive unfolding with decreased stability (p.H65R, p.T191M, p.I278T and p.R369C). The extent of the unfolding inversely correlated with the previously determined degree of tetrameric assembly and with the catalytic activity. In contrast, mutants bearing aminoacid substitutions in the C-terminal regulatory domain (p.R439Q and p.D444N) had increased global stability with decreased flexibility. This study shows that proteolytic techniques can reveal conformational abnormalities even for CBS mutants that have activity and/or a degree of assembly similar to the wild-type enzyme. We present here a methodological strategy that may be used in cell lysates to evaluate properties of proteins that tend to misfold and aggregate and that may be important for conformational studies of disease-causing mutations in the field of inborn errors of metabolism.  相似文献   
99.
100.
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