Therapeutic approaches of diametaphyseal radius fractures in children.

BACKGROUND: There are clear standards for when to operate on both distal epiphyseal and diaphyseal forearm fractures in children. However, paediatric surgeons are often faced with fractures in the transition zone between metaphysis and diaphysis. This aim of the study is to compare different treatment approaches for diametaphyseal forearm fractures, to classify different types of these fractures, and to define further assessment parameters and treatment recommendations. METHODS: This retrospective study included all patients with diametaphyseal radial fractures who were seen at a paediatric surgery clinic between 01.01.2010 and 31.12.2013. Patients were treated either non-surgically (C) or surgically using bicortical Kirschner wire (BC-KW), intramedullary K-wire (IM-KW), elastic stable intramedullary nailing (ESIN), or combined bicortical and intramedullary K-wire (BCIM-KW). RESULTS: During the study period, 547 patients presented with forearm fractures of which 88 patients (16%) had a fracture in the diametaphyseal region. The majority of diametaphyseal fractures were greenstick fractures (54.4%) followed by transverse fractures (44.3%). Distal fractures were predominantly treated with bicortical K-wiring (BC-KW, 40.5%) or non-surgically (C, 26.2%). Proximal fractures were treated by ESIN osteosynthesis (50%), followed by IM-KW (30%). Intermediate fractures were just as likely to be treated with one out of the 5 above-mentioned techniques. The ulna was involved in 64 of 88 cases. Depending on the type of fracture, it was treated either by ESIN osteosynthesis or non-surgically. No superior operative technique was identified. CONCLUSIONS: The description of diametaphyseal fractures as a separate entity is important, because the therapy of these fractures is heterogeneous and challenging. A classification into proximal, intermediate, and distal may be useful in clinical decision-making. Despite the retrospective nature of this study, our data suggest that the use of a K-wire or combined technique BCIM-KW-technique, whenever technically feasible, achieves better radiological results without secondary dislocation. Further prospective studies are needed to provide better guidance to trauma surgeons.

SNP g.1007A>G within the porcine DNAL4 gene affects sperm motility traits and percentage of midpiece abnormalities.

The flagellar beating of a spermatozoa's axoneme is caused by the varying activation and inactivation of dynein molecules. Dynein, axonemal, light chain 4 (DNAL4) is a functional candidate gene for sperm motility as it encodes a small subunit of the dyneins. We resequenced the porcine DNAL4 using three artificial insemination (AI) boars each with high (>68%) or low (<60%) motility, and detected 23 SNP. These were then genotyped for 82 AI boars. Using spermatological records, significantly negative genetic correlations between ejaculate volume (VOL) and the further spermatological parameters concentration (CONC) (r = -.43), motility of undiluted semen (MOTUD) (r = -.09), motility after 24 h (MOT1) (r = -.17) and after 48 hr (MOT2) (r = -.23) were estimated. Significantly positive correlations existed between CONC and MOT1 (r = .07) as well as MOT2 (r = .10), between MOTUD and MOT1 (r = .33), between MOTUD and MOT2 (r = .36), and finally between MOT1 and MOT2 (r = .70). Significantly negatively correlated were all motility traits with the parameters abnormal acrosome (AA) (MOTUD r = -.06; MOT1 r = -.08, and MOT2 r = -.1) and presence of cytoplasmic droplet (CD) (MOTUD r = -.07; MOT1 r = -.08; MOT2 r = -.07). Association analyses (single marker regression model; SMR) propose that SNP g.1007A>G, located in the second intron, reduces motility significantly (MOTUD -4.59%; MOT1 -10.33%; MOT2 -19.37%). According to the dominant-recessive model (DRM), genotype AA is always superior compared to genotypes AG and GG (i.e. MOTUD 67.67%, 64.16% and 53.91%; MOT1 54.17%, 43.75% and 28.44%; MOT2 44.12%, 24.91% and 4.97%). The average effect of gene substitution (g.1007A>G) on abnormal midpiece (AM) was 0.71%, the genotypic values-as expressed by LSmeans-were 0.1 (AA) and 0.81 (AG).

Sex selection of sperm in farm animals: status report and developmental prospects.

Pre-selection of spermatozoa based on the relative DNA difference between X- and Y-chromosome bearing populations by flow cytometry is an established method that has been introduced into commercial cattle production. Although several important improvements have increased the sort efficiency, the fertilising ability of sexed spermatozoa based on offspring per insemination is still behind farmers' expectations. The main stress factors, especially on mitochondria, that reduce the lifespan of spermatozoa are described, and new technical as well as biological solutions to maintain the natural sperm integrity and to increase the sorting efficiency are discussed. Among these methods are the identification of Y-chromosome bearing spermatozoa by bi-functionalised gold nanoparticles and triplex hybridisation in vivo as well as new laser-controlled deflection system that replaces the deflection of spermatozoa in the electrostatic field. Additionally, as well as a new nonsurgical transfer system of spermatozoa into the oviduct of cows has been developed and allows a significant reduction of spermatozoa per transfer. Altogether, the improvements made in the recent years will allow a broader use of sex-sorted spermatozoa even in those species that require more cells than cows and sheep.

Further resolution of porcine phylogeny in Southeast Asia by Thai mtDNA haplotypes.

The mtDNA control region of 72 Thai native pigs and 11 Thai wild boars indigenous to Northern Thailand was comparatively sequenced. In total, 36 nucleotide variations that accounted for 24 haplotypes have been described (TNH01 to TNH20 and TWH01 to TWH04). These haplotypes and further publicly available mtDNA haplotypes were used to assess phylogenetic relationships. Twenty-three of the 24 haplotypes became integrated into the Asian clade of the phylogenetic tree and eight of them recapitulated another major cluster of haplotypes within this clade (Thai haplogroup, THG). Only haplotype TNH01 fit in with the European clade of the phylogenetic tree. An additional analysis using 510 bp of the mtDNA incorporated the THG haplotypes in to clade MTSEA (mountainous and Southeast Asian distribution) to form haplogroup MTSEA-THG. Recently, MTSEA was renamed in MC3. MC3 contains only signatures of pigs scattered across the Indo-Burma Biodiversity Hotspot (IBBH), a region including Thailand to the Kra Isthmus. Here we propose a putative independent porcine domestication event in South-east Asia (SEA). All haplotypes of haplogroup MTSEA-THG have revealed unique and previously unknown nucleotide signatures at positions 24 (nucleotide A) and at positions 183 (nucleotide C) that differentiate them from all other porcine mtDNA haplotypes.

Molecular analysis of carbohydrate N-acetylgalactosamine 4-O sulfotransferase 8 (CHST8) as a candidate gene for bovine spongiform encephalopathy susceptibility.

Endogenous prion proteins (PrP) play the central role in the pathogenesis of transmissible spongiform encephalopathies. The carbohydrate N-acetylgalactosamine 4-O sulfotransferase 8 (CHST8) promotes the conversion of the cellular PrP(C) into the pathogenic PrP(d). Six sequence variants within the CHST8 gene were identified by comparative sequencing and genotyped for a sample of 623 animals comprising bovine spongiform encephalopathy (BSE)-affected and healthy control cows representing German Fleckvieh (German Simmental), German Holstein (Holstein-Friesian) and Brown Swiss. Significant differences in the allele, genotype and haplotype frequencies between BSE-affected and healthy cows indicate an association of sequence variant g.37254017G>T with the development of the disease in Brown Swiss cattle.

[Social network analysis of interdisciplinary cooperation and networking in early prevention and intervention. A pilot study]. / Soziale Netzwerkanalyse interdisziplinärer Kooperation und Vernetzung in den Frühen Hilfen. Eine Pilotuntersuchung.

Child protection can only be successfully solved by interdisciplinary cooperation and networking. The individual, heterogeneous, and complex needs of families cannot be met sufficiently by one profession alone. To guarantee efficient interdisciplinary cooperation, there should not be any gaps in the network. In addition, each actor in the network should be placed at an optimal position regarding function, responsibilities, and skills. Actors that serve as allocators, such as pediatricians or youth welfare officers, should be in key player positions within the network. Furthermore, successful child protection is preventive and starts early. Social network analysis is an adequate technique to assess network structures and to plan interventions to improve networking. In addition, it is very useful to evaluate the effectiveness of interventions like round tables. We present data from our pilot project which was part of "Guter Start ins Kinderleben" ("a good start into a child's life"). Exemplary network data from one community show that networking is already quite effective with a satisfactory mean density throughout the network. There is potential for improvement in cooperation, especially at the interface between the child welfare and health systems.

Long-term functional outcome after hyperthermic isolated limb perfusion (HILP).

BACKGROUND: One of the biological characteristics of melanoma is the locoregional development of metastases that are difficult to treat by conventional tumour mass reduction. Locoregionally metastasised melanoma of the limb can effectively be treated by hyperthermic isolated limb perfusion (HILP). Postoperative complication rates are acceptable. Only few studies have examined long-term complications. This is the reason why we followed up patients in respect of long-term physical and psychological complications after HILP. MATERIALS AND METHODS: 312 patients with melanoma of the limb underwent HILP in our department between 1977 and 1983. Eighty-two patients that were still alive and no older than 80 years at the time of follow-up were contacted and invited to a physical examination. On average, follow-up took place 20 years after HILP. Thirty-nine patients were willing to participate in the study. Twelve of these patients were male and 27 female. The average age was 63.1 years (range 41 to 79). The average age at the point of perfusion was 42.1 years (range 19 to 59). In 10 cases the upper extremity was involved, in 29 patients the lower extremity. Patients were questioned on impairment of daily life and their health status using a standardised questionnaire. A physical examination was performed to document the impairments quantitatively. Ranges of motion, circumference and neurological deficits of the operated limbs were compared to the healthy limbs. RESULTS: At the time of follow-up examination all patients were without recurrent disease. A definite correlation between impairment of the general health condition and the operation could only be found in one patient with persisting lymph oedema. Thirteen patients still wore elastic stockings during the day, 9 of which regularly underwent lymphatic drainage. Most of the patients (58%) saw an improvement of their condition due to the treatment. 67% of the patients reported not having any or only slight impairment of everyday life. Only a few cases had disadvantages in their social and working life due to the perfusion. The physical examination of the upper limb showed an impaired range of motion of the shoulder in all planes in 50% of the patients. Relevant decrease in range of motion in the elbow was seen in two patients. The other examination results showed no significant differences in comparison to the healthy arm. The analysis of the lower limb showed relevant clinical reduction of range of motion in all three major joints. Significant differences were also found in the circumference of the leg compared to the healthy side. SUMMARY: According to our results and results from the literature it was possible to show that hyperthermic isolated limb perfusion is associated with an elevated risk of persisting impairment of range of motion of the treated limb. The impaired function is due to a persistent swelling of the limb because of lymph oedema on the one hand and local toxicity to the ligaments of the joints on the other. Response rates and results of HILP have greatly improved in the last years due to numerous modifications so that this treatment is the method of choice in locoregionally metastasised melanoma of the limb in spite of the long-term complication rate.

[Hepaticolithiasis. Rare benign disease of the intrahepatic bile ducts]. / Hepatikolithiasis. Seltene benigne Erkrankung der intrahepatischen Gallenwege.

Hepaticolithiasis is a rare disease of the intrahepatic bile ducts endemic to east Asia which also is known as oriental cholangiohepatitis. Beside strictures and metabolic disturbance, the main cause of intrahepatic stones is acquired or congenital malformation of the intrahepatic biliary ducts. In the following we show a case of hepaticolithiasis and concurrent pancreatic metaplasia.

Sequence analysis of the equine SLC26A2 gene locus on chromosome 14q15-->q21.

The solute carrier family 26, member 2 (SLC26A2) gene belongs to a family of multifunctional anion exchangers. Mutations in the human SLC26A2 gene are associated with autosomal recessively inherited chondrodysplasias. Hence, we postulate that the equine SLC26A2 could be a candidate gene for conformational traits in horses. An equine BAC clone harboring the SLC26A2 gene was isolated. The complete 142,625 bp insert sequence of this clone was determined by transposon sequencing. Together with the SLC26A2 gene the BAC clone contains four genes, i.e. the macrophage colony stimulating factor 1 receptor precursor (CSF1R), KIAA0194 protein gene similar to the SMF protein (KIAA0194), a tigger transposable element derived 14 (TIGD14), the 3'-5'-cyclic GMP phosphodiesterase alpha-chain (EC 3.1.4.35) and one unidentified open reading frame. The equine SLC26A2 gene encompassing 6,152 bp consists of two exons. The complete open reading frame of 2,211 bp encodes a protein of 736 amino acids. A comparison of the amino acid sequence with other mammalian orthologs revealed homologies with identity in a range between 80% and 88%. By contrast, the equine SLC26A2 protein lacks five C-terminal amino acids. Four single nucleotide polymorphisms (SNP) were identified (three synonymous and one non-synonymous variant Ser210Leu) in the coding region by comparative sequencing of 50 DNA samples representing the German Riding horse. Allele frequencies and distribution were further evaluated in a variety of different breeds: Arabians (for all four SNPs), Old Kladrub Horses, Draught Horses (including Westphalian Draught Horses, Rheinish Westphalian Draught Horses, Saxon-Thuringia Coldbloods, Altmarker Coldbloods), American Saddlebreds, Miniature Horses, Australian Riding Ponies, Appaloosa, Morgan Horses, and Lipizzaner for C629T (Ser210Leu) alone. No animal carrying the homozygous genotype TT has been detected. The overall frequency of the newly described variant T is low (between 2% and 6%). Simulation studies on the protein conformation predict structural protein changes mediated by the SNP.

CO2 permeability and carbonic anhydrase activity of rat cardiomyocytes.

AIM: To determine the CO2 permeability (PCO2 ) of plasma membranes of cardiomyocytes. These cells were chosen because heart possesses the highest rate of O2 consumption/CO2 production in the body. METHODS: Cardiomyocytes were isolated from rat hearts using the Langendorff technique. Cardiomyocyte suspensions exhibited a vitality of 2-14% and were studied by the previously described mass spectrometric 18 O-exchange technique deriving PCO2 . We showed by mass spectrometry and by carbonic anhydrase (CA) staining that non-vital cardiomyocytes are free of CA and thus do not contribute to the mass spectrometric signal, which is determined exclusively by the fully functional vital cardiomyocytes. RESULTS: Lysed cardiomyocytes yielded an intracellular CA activity for vital cells of 5070; that is, the rate of CO2 hydration inside the cell is accelerated 5071-fold. Using this number, analyses of the mass spectrometric recordings from cardiomyocyte suspensions yield a PCO2 of 0.10 cm s-1 (SD ± 0.06, n = 15) at 37 °C. CONCLUSION: In comparison with the PCO2 of other cells, this value is quite high and about identical to that of the human red cell membrane. As no major protein CO2 channels such as aquaporins 1 and 4 are present in rat cardiac sarcolemma, the high PCO2 of this membrane is likely due to its low cholesterol content of about 0.2 (mol cholesterol)·(mol total membrane lipids)-1 . Previous work predicted a PCO2 of ≥0.1 cm s-1 from this level of cholesterol. We conclude that the low cholesterol establishes a PCO2 high enough to render the membrane resistance to CO2 diffusion almost negligible, even under conditions of maximal O2 consumption of the heart.

Hyperthermic isolated limb perfusion (HILP) in malignant melanoma. Experience with 101 patients.

AIMS: To analyse results with a standardized HILP procedure in terms of response rate, recurrence pattern and complication rate. PATIENTS AND METHODS: From 1992 to 2003 HILP with melphalan and dactinomycin was performed in 101 patients with loco-regional metastases of malignant melanoma of the limbs. Among these were 66 women and 35 men with a median age of 62 years. Forty patients were in M. D. Anderson stage IIIA, 51 patients in stage IIIAB and 9 had stage IV disease at the time of perfusion. If not been done before, regional lymph node dissection preceded limb perfusion in the same setting. RESULTS: A complete response (CR) was observed in 58 out of 87 evaluable patients. Twenty-one patients achieved a partial response (PR) and eight patients were non-responders. The overall response rate was 90.8%. The median recurrence-free interval after CR was 21 months. Severe toxicity (Wieberdink IV/V) was observed in five patients necessitating fasciotomy in four of them and above knee amputation in one patient. All further cases presented with grade II-III toxicity. The overall survival was 42 months, with a 5-year survival rate of 38%. Survival significantly differed according to stage of disease. CONCLUSION: HILP is an effective treatment for loco-regional tumour relapse of malignant melanoma of the extremities and has improved by modification of technique. In the absence of regional lymph node and distant metastases long-term survival can be achieved in responders.

[The "inspection jejunostomy" after complex reconstructions of the central bile ducts]. / Anlage eines inspektionsstomas bei komplexen rekonstruktionen an den zentralen gallengängen.

INTRODUCTION: Hutson and Russell described in 1984 a surgical technique, where a modified Roux-en-Y hepaticojejunostomy with the afferent limb brought up as jejunostomy after complex reconstructions of the central bile duct was performed [4]. It facilitates endoscopic retrograde access to the biliary tree for control examinations and biopsies in complicated reconstructive procedures after bile duct resection. We report our experience with this operative procedure. METHODS: After having performed complicated bile duct resection, the reconstruction was performed as a modified Roux-en-Y hepaticojejunostomy with the 20 cm afferent limb brought up as terminal jejunostomy in the right upper abdominal quadrant. Postoperative follow-up comprised endoscopic and radiologic controls of the biliary tree every 3 months for one year; ileostomy resection was performed one year later if the postoperative course was undisturbed. RESULTS: From 03/1995 to 07/2006 we performed this operation in 25 patients (mean age 62 yrs.). Indications were previous lesions of the common bile duct after laparoscopic (n = 10) or open cholecystectomy (n = 5), common bile duct resections in cholangiocellular carcinoma and gallbladder carcinoma with unclear intraoperative safety margins (n = 4), malignant granulosa cell tumour and simultaneous cholangiocellular carcinoma, focal nodal hyperplasia, Mirizzi-syndrome, cystadenoma of the pancreas head, cyst of ecchinococus granulosos and one patient with intrahepatic recurrent stone formation after orthotopic liver transplantation. The endoscopic and radiologic (cholangiography) diagnostic procedures--performed every 3 months postoperatively--were uneventful. CONCLUSIONS: The modified Roux-en-Y hepaticojejunostomy with the afferent limb brought up as jejunostomy permits good control and intervention possibilities in complicated bile duct surgery after bile duct lesions, tumor resection with unclear resectional margins and in recurrent intrahepatic stone formation.

Communication requested: Boar semen transport through the uterus and possible consequences for insemination.

Recent insemination techniques bypass the interactions between sperm and the uterine wall because the semen is deposited deep into the tip of uterine horn or directly into the oviduct. Such techniques allow high dilution of the ejaculates. After normal mating, semen entering the uterus communicates with the uterine milieu. Intact sperm of high mitochondrial membrane potential bind to uterine epithelial cells, whereas most of the unbound sperm in the uterine lumen have damaged membranes. Lectins are the most likely factors to mediate these sperm-uterine interactions. The lectin wheat germ agglutinin is known to induce the strongest binding of sperm, whereas binding is impaired when sialic acid receptors are blocked by wheat germ agglutinin. This suggests that sialic acid is involved in porcine sperm-endometrium interactions, and it is hypothesized that the use of a semen extender supplemented with sialidase would allow insemination with reduced sperm numbers. A lack of contact of sperm and seminal plasma with the uterine wall, as a result of deep insemination, may adversely affect (1) events during ovulation, (2) induction of immunologic tolerance against paternal antigens, (3) preparation of the endometrium for implantation and placentation, and (4) immunologic support required for the fetus during pregnancy. Seminal plasma is known to signal post-insemination changes in the uterine endometrium involving the redistribution of leukocytes. This may involve migration of leukocytes from the uterine wall to the ovary, as seminal plasma particularly increases the appearance of the major histocompatibility complex class II-positive cells. Uterine epithelial cells respond to sperm binding by the production of pro- or anti-inflammatory cytokines. These cytokines may include synchronizing substances, transferred through a counter-current pathway to the ipsilateral ovary, thereby accelerating the final maturation of preovulatory follicles and advancing time of ovulation. In several species, an ovulation-inducing factor exists in seminal plasma, first identified as ß-nerve growth factor in camelid semen, indicating another pathway that influences the hypothalamic-pituitary-gonadal axis. In summary, low-dose inseminations may not necessarily require semen deposition deep into the uterine horn, as binding inhibitors can circumvent the binding of sperm to the uterine wall. However, subsequent immune-relevant events that control ovulation and prepare the uterine milieu for the developing embryo should be taken into account.

[Inspection jejunostomy after complex reconstruction of the central bile duct. Indication, description, and personal experience]. / Das Inspektionsstoma nach komplexen Rekonstruktionen an den zentralen Gallengängen. Indikationen, Beschreibung der Operationsmethode und Erfahrungsbericht.

INTRODUCTION: A modified Roux-en-Y hepaticojejunostomy that allows postoperative endoscopic access was first described in 1984. We report our experience with this operative procedure. METHODS: After complicated bile duct resection, reconstruction was performed as a modified Roux-en-Y hepaticojejunostomy, with the 20 cm afferent limb brought up as in terminal jejunostomy in the right upper abdominal quadrant. Postoperative follow-up consisted of endoscopic and radiologic control of the biliary tree every 3 months for 1 year; ileostomy resection was performed 1 year later if the postoperative course was undisturbed. RESULTS: From March 1995 to February 2002, we performed this operation in 17 patients (mean age 56 years). The endoscopic and radiologic (cholangiography) diagnostic procedures--every 3 months postoperatively--were uneventful. CONCLUSIONS: The modified Roux-en-Y hepaticojejunostomy described here permits good control and intervention in complicated surgery for bile duct lesions, tumor resection with unclear resectional margins, and recurrent intrahepatic stone formation.

Molecular characterization of porcine hyaluronidase genes 1, 2, and 3 clustered on SSC13q21.

Hyaluronidase genes (HYAL) encode hyaluronidase enzymes required for hyaluronan degradation. Both in humans and in mouse, clustered hyaluronidase genes have been identified. Here, the porcine hyaluronidase cluster consisting of genes HYAL1, HYAL2 and HYAL3 was characterized. The porcine cDNA sequences and proteins share homologies to human orthologs of 85 and 81% for HYAL1, 87 and 89% for HYAL2 and 86 and 83% for HYAL3, respectively. The porcine hyaluronidase proteins approximately share a 40% homology with each other. Furthermore, genes FUS1 and FUS2 were found within this cluster, which was assigned to SSC13q21. A total of seven SNPs were detected in the genes (four in HYAL1, two in HYAL2 and one in HYAL3). Three of the four SNPs in HYAL1 led to amino acid exchanges (C622G --> Asp24 to Glu; C633T --> Pro28 to Leu, and G1298T --> Ala250 to Ser). The amino acid replacements induce putative changes in the extended strand at Asp24, in the extended strand and the random coil at Pro28, and finally in the random coil and the alpha helix at Ala250. Frequency estimations for four SNPs located in genes HYAL1 and HYAL3 using animals (n = 295) of nine European and six Chinese pig breeds indicated several significant deviations. For example, there were no significant differences in allele frequencies between pigs representing breeds Hampshire and Jiangquhai at SNP C633T (HYAL1), but between Hampshire respectively Jiangquhai animals and Rongchang pigs. Analysis of the same breeds at SNP C588T (HYAL3) indicates significant differences between Hampshire and Jiangquhai respectively Rongchang, but not between Jiangquhai and Rongchang. The breed Göttingen Minipig displayed significant differences concerning two SNPs with respect to the other European pig breeds tested. For all three hyaluronidase genes, N-glycosylation sites are typical. For HYAL2 the lysosomal character was proven. The catalytic site responsible for HAase activity is conserved in the three enzymes. Expression of hyaluronidases was determined by RT-PCR and quantitative PCR. Broad gene expression was observed in different tissues for the three genes, respectively.

Characterization and chromosome localization of a processed pseudogene related to the bovine laminin receptor gene family.

A bovine BAC clone containing a processed laminin receptor pseudogene (LAMR1P) has been isolated and characterized. A 2,901-bp sequence was produced from the clone, of which 1,187 bp represented seven identifiable exon-like domains, but no intervening sequences. The pseudogene sequence reveals several transversions and transitions, as well as insertions and deletions. A premature stop codon motif is present at nucleotide position 115 located in the exon-2-like domain. Physical mapping of the gene was performed by FISH and RH panel mapping and assigned LAMR1P to BTA4q24-->q26 with the closest linkage to BM6458 (19 cR, LOD score of 11.6). The functional laminin receptor putatively plays an important role in the transmission of bovine spongiform encephalopathy (BSE). In this process, the receptor supposedly acts as the binding site for prion proteins to enter mammalian cells. Considering the existence of several human laminin receptor pseudogenes forming a complex family, any knowledge of even pseudogene sequences might be helpful to isolate the functional bovine laminin receptor gene.

Tumor biology of mucosa-associated lymphoid tissue lymphomas.

Extranodal lymphomas arising at mucosal sites exhibit clinicopathological features that suggest a closer relationship of these tumors to the structure and function of mucosa-associated lymphoid tissue (MALT) than to lymph nodes. The factors that induce MALT in these tissues are operative in early MALT lymphoma development and the progressive independence on T-cell help defines late stages of MALT lymphoma genesis.

Receptor analysis of idiotype antibodies derived from MALT type B-cell lymphoma hybridomas.

The generation of human antibodies derived from extranodal MALT type B-cell lymphomas allows to evaluate steps in their pathogenesis as well as to establish potential immunological therapies. Intraclonal diversity and the existence of bystander nonmalignant B-cells outline the need for reliable identification of the tumor immunoglobulin representing hybridomas. Human heterohybridomas were generated from five cases of MALT type B-cell lymphomas (4 low grade, one high grade) by the fusion of lymphoma B-cells with the murine myeloma cell line NSO and tested for isotype identity with the tumor. RT-PCR using VH Fr1/JH primers was performed with RNA of tumors and hybridomas that share the same isotype with the tumor. PCR-products were sequenced directly. In each case lymphomas were hybridized with a comparable fusion efficiency. DNA sequence analysis of the immunoglobulin heavy chain identified one or more hybridomas derived from the tumor. However some other hybridomas which share the same isotype with the tumor, may be different in their VH family or their sequence. Hybridomas can be used as a tool for the research on the MALT lymphoma immunoglobulin receptor. For the identification of tumor immunoglobulin, secreting hybridomas sequencing and the check of molecular identity is indispensable after isotype determination.

[Impaired CD95-(Fas,APO-1-)apoptosis regulation is a progression factor in early MALT-type lymphoma genesis]. / Eine gestörte CD95-(Fas,APO-1-)vermittelte Apoptoseregulation ist ein Progressionsfaktor in der frühen MALT-Typ-Lymphomgenese.

BACKGROUND: MALT-type lymphomas are B cell tumors arising for so far unknown reasons on the background of chronic inflammation, e.g. Helicobacter pylori-associated gastritis. T cells are supposed to have a positive impact on tumor growth, but fail in their control function. We therefore examined the interaction of T cells with malignant B cells in vitro and focused on T cell control which normally operates by CD95L/CD95-mediated apoptosis. PATIENTS AND METHODS: Malignant B cells were isolated from tumor tissues of 7 patients with low-grade MALT-type lymphoma and 4 patients with DLBL and cocultured in vitro with activated T cells. Normal memory B cells were used as control. We developed a T/B coculture assay for investigation of CD95L/CD95-mediated apoptosis. The influence of T cells on CD95 expression and survival of B cells was measured by FACS analysis. RESULTS: Activated T cells induced CD95 expression and thus enhanced sensitivity to CD95L-mediated apoptosis in normal memory B cells. However, malignant B cells from 3 out of 7 low-grade MALT-type lymphomas and all 4 gastric DLBLs resisted apoptosis, although the cells showed enhanced CD95 expression. CONCLUSION: Resistance to CD95L/CD95-mediated apoptosis allows malignant B cells from MALT-type lymphoma to escape T cell control and leads to prolonged survival. This phenomenon acts as a progression factor in early lymphomagenesis.