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Biomedical subjects

F Bosch

Publications and source records attributed to F Bosch.

At least 19 recordsLinked to original sources
PubMed2001

Prognostic features and outcome in patients with diffuse large B-cell lymphoma who do not achieve a complete response to first-line regimens.

BACKGROUND: The current study was conducted to analyze the outcome and prognostic factors of patients with diffuse large B-cell lymphoma (DLCL) who did not achieve a complete response (CR) to first-line treatment. METHODS: The current study was comprised of 83 patients (43 males and 40 females with a median age of 62 years) who did not achieve a CR (58 of whom had primary refractory disease and 25 of whom achieved a partial response) with initial treatment (doxorubicin-containing regimens in 87% of cases) from a series of 239 patients consecutively diagnosed with DLCL at a single institution. Initial variables, response to therapy, and salvage treatment were analyzed to predict survival. RESULTS: Compared with patients who achieved a CR, nonresponders or partial responders more frequently were of advanced age and had a poor performance status (PS), B-symptoms, advanced stage of disease, bone marrow infiltration, increased serum lactate dehydrogenase, and a high-risk International Prognostic Index. Among the 58 patients with primary refractory disease, 18 died during initial treatment due to toxicity (14 patients) or disease progression (4 patients). The main variables predicting early death were a poor PS, age > 60 years, and an immunoblastic DLCL subtype. Twenty-five of these 58 patients were able to receive salvage regimens, with only 1 of them achieving a CR. The median survival for this group of patients was 10 months. With regard to those patients achieving a partial response, 18 of the 25 patients received further therapy with 28% of them achieving a CR. The median survival was 23 months. The degree of the response was found to be the only significant variable with which to predict survival, with 2-year survival rates of 4% and 40%, respectively, for patients with primary refractory disease and patients who achieved a partial response. CONCLUSIONS: The prognosis of patients with primarily refractory DLCL is extremely unfavorable, whereas that of patients who achieve a partial response is slightly better. The inclusion of these patients in experimental trials is limited due to their tendency to be of an older age and to have a poor general status.

Adolescent↗
PubMed2001

Nucleotide sequence, transcription map, and mutation analysis of the 13q14 chromosomal region deleted in B-cell chronic lymphocytic leukemia.

Deletions of the 13q14 chromosome region are associated with B-cell chronic lymphocytic leukemia (B-CLL) and several other types of cancer, suggesting the presence of a tumor suppressor gene. In previous studies the minimal region of deletion (MDR) was mapped to a less than 300-kilobase (kb) interval bordered by the markers 173a12-82 and 138G4/1.3R. For the identification of the putative tumor suppressor gene, the entire MDR (approximately 347 kb) has been sequenced, and transcribed regions have been identified by exon trapping, EST-based full-length complementary DNA cloning, database homology searches, and computer-assisted gene prediction analyses. The MDR contains 2 pseudogenes and 3 transcribed genes: CAR, encoding a putative RING-finger containing protein; 1B4/Leu2, generating noncoding transcripts; and EST70/Leu1, probably representing another noncoding gene (longest open reading frame of 78 codons). These genes have been sequenced in 20 B-CLL cases with 13q14 hemizygous deletion, and no mutations were found. Moreover, no somatic variants were found in the entire MDR analyzed for nucleotide substitutions by a combination of direct sequencing and fluorescence-assisted mismatch analysis in 5 B-CLL cases displaying 13q14-monoallelic deletion. The nondeleted allele of the CAR and EST70/Leu1 genes was expressed in B-CLL specimens, including those with monoallelic loss, whereas no expression of 1B4/Leu2 was detectable in B-CLL, regardless of the 13q14 status. These results indicate that allelic loss and mutation of a gene within the MDR is an unlikely pathogenetic mechanism for B-CLL. However, haplo-insufficiency of one of the identified genes may contribute to tumorigenesis. (Blood. 2001;97:2098-2104)

Animals↗
PubMed2001

Near-threshold photoionization of hydrogenlike uranium studied in ion-atom collisions via the time-reversed process.

Radiative electron capture, the time-reversed photoionization process occurring in ion-atom collisions, provides presently the only access to photoionization studies for very highly charged ions. By applying the deceleration mode of the ESR storage ring, we studied this process in low-energy collisions of bare uranium ions with low- Z target atoms. This technique allows us to extend the current information about photoionization to much lower energies than those accessible for neutral heavy elements in the direct reaction channel. The results prove that for high- Z systems, higher-order multipole contributions and magnetic corrections persist even at energies close to the threshold.

Journal Article↗
PubMed2001

Strong evidence for enhanced multiple electron capture from surfaces in 46 MeV/u Pb81+ collisions with thin carbon foils.

Strong evidence has been found for enhanced multiple electron capture into 46 MeV/u Pb81+ with a significant contribution from the entrance surface of thin carbon foils. Capture of up to five electrons has been observed. The multiple electron capture yield is found to increase with decreasing target thickness for thin targets. A simple model describing the data and showing the importance of capture from surfaces is discussed. Further evidence is found for a pronounced asymmetry between electron capture at the entrance and the exit surfaces. Absolute yields for multiple electron capture and projectile ionization are presented. The experimental total cross sections for single capture and ionization agree well with theory.

Journal Article↗
PubMed2001

Cutaneous lymphocyte-associated antigen (CLA) expression in a lymphoblastoid mantle cell lymphoma presenting with skin lesions. Comparison with other clinicopathologic presentations of mantle cell lymphoma.

BACKGROUND: Cutaneous lymphocyte-associated antigen (CLA) is a lymphocyte homing receptor selectively expressed by T cells of the cutaneous immune system and their malignant counterpart, that is to say, cutaneous T-cell lymphomas. However it is absent in the vast mayority of other T-cell malignancies and B-cell lineage lymphomas irrespective on primary tumor site. METHODS: Expression of CLA was investigated on six cases of mantle cell lymphoma (MCL) which differed in their histopathological subtype (typical or blastic) and their tendency to infiltrate skin and/or central nervous system (CNS). RESULTS: CLA immunostaining on neoplastic cells was only observed in a 61-year-old female suffering from a lymphoblastoid MCL which clinically presented with specific skin lesions and further developped CNS disease. In this patient, coexpression of CLA with MCL markers (CD20 and CD5) was confirmed by conventional immunohistochemistry and double immunofluorescence studies. CONCLUSIONS: To our knowledge, CLA immunoreactivity on B-cell lymphomas has not beeen previously reported. The expression of this skin-related adhesion molecule on malignant MCL cells could explain the clinical behavior of our case which presented and relapsed with cutaneous lesions. However, CLA seems not to be a MCL marker nor a CNS-related adhesion molecule. The authors review the clinical and histopathological characteristics of MCL-specific skin lesions and their diagnostic clues based on cell morphology, immunohistochemistry and molecular investigations.

Adult↗
PubMed2001

Microsatellite instability analysis in typical and progressed mantle cell lymphoma and B-cell chronic lymphocytic leukemia.

BACKGROUND AND OBJECTIVES: Microsatellite instability (MSI) is characterized by tumor-associated alterations in the germline size of microsatellite repeats caused by a reduced efficacy of the DNA mismatch repair machinery. The aim of this study was to investigate the presence of MSI in a number of cases of indolent and aggressive mantle cell lymphoma (MCL) and B-cell chronic lymphocytic leukemia (B-CLL) to determine its possible role in the initial development and progression of these disorders. DESIGN AND METHODS: We examined the presence of MSI in 28 B-CLL, 24 typical and 4 transformed B-CLL (Richter's syndrome) and 29 MCL, 19 typical and 10 blastoid variants by using a panel of 10 microsatellite markers and analyzed them using an AbiPrism 310 DNA sequencer. Fisher's exact test was used to compare categorical variables and Mann-Whitney's U-test for continuous variables. RESULTS: MSI alterations were not observed in any case of MCL or Richter's syndrome and in only three (13%) patients with typical B-CLL. Two of these patients also had loss of heterozygosity in one of the 10 sites examined. These patients presented with a more advanced stage, diffuse bone marrow involvement, and poorer performance status than patients without these alterations. INTERPRETATION AND CONCLUSIONS: These findings indicate that MSI is not involved in the pathogenesis or progression of B-CLL and MCL but may appear in a small subset of patients with advanced B-CLL.

Adult↗
PubMed2000

1s lamb shift in hydrogenlike uranium measured on cooled, decelerated ion beams.

The Lyman- alpha transitions of hydrogenlike uranium associated with electron capture were measured in collisions of stored bare U (92+) ions with gaseous targets at the storage ring ESR. By applying the deceleration technique, the experiment was performed at slow collision energies in order to reduce the uncertainties associated with Doppler corrections. From the measured centroid energies, a ground state Lamb shift of 468 eV+/-13 eV is deduced which gives the most precise test of quantum electrodynamics for a single electron system in the strong field regime. In particular, the technique applied paves the way towards the 1 eV precision regime.

Journal Article↗
PubMed2000

Expression of glucokinase in skeletal muscle: a new approach to counteract diabetic hyperglycemia.

Chronic hyperglycemia is responsible for diabetes-specific microvascular and macrovascular complications. To reduce hyperglycemia, key tissues may be engineered to take up glucose. To determine whether an increase in skeletal muscle glucose phosphorylation leads to increased glucose uptake and to normalization of diabetic alterations, the liver enzyme glucokinase (GK) was expressed in muscle of transgenic mice. GK has a high Km for glucose and its activity is not inhibited by glucose 6-phosphate. The presence of GK activity in skeletal muscle resulted in increased concentrations of glucose 6-phosphate and glycogen. These mice showed lower glycemia and insulinemia, increased serum lactate levels, and higher blood glucose disposal after an intraperitoneal glucose tolerance test. Furthermore, transgenic mice were more sensitive to injection of low doses of insulin, which led to increased blood glucose disposal. In addition, streptozotocin (STZ)-treated transgenic mice showed lower levels of blood glucose than STZ-treated controls and maintained body weight. Moreover, injection of insulin to STZ-treated transgenic mice led to normoglycemia, while STZ-treated control mice remained highly hyperglycemic. Thus, these results are consistent with a key role of glucose phosphorylation in regulating glucose metabolism in skeletal muscle. Furthermore, this study suggests that engineering skeletal muscle to express GK may be a new approach to the therapy of diabetes mellitus.

Animals↗
PubMed2000

Hybrid chemotherapy consisting of cyclophosphamide, vincristine, procarbazine, prednisone, doxorubicin, bleomycin, and vinblastine (C-MOPP/ABV) as first-line treatment for patients with advanced Hodgkin disease.

BACKGROUND: Combination chemotherapy, including hybrid regimens, is the standard treatment for patients with advanced Hodgkin disease (HD). Although a prolonged complete response (CR) is achieved in up to 70-80% of patients, long term complications, such as secondary leukemia, are of concern. Cyclophosphamide, vincristine, procarbazine, prednisone, doxorubicin, bleomycin, and vinblastine (C-MOPP/ABV) is a hybrid chemotherapy in which cyclophosphamide is substituted for mechlorethamine, an agent that has been implicated as the cause of secondary malignancies. METHODS: Seventy-three patients (37 males and 36 females; median age, 35 years) diagnosed with Stage III or IV HD or Stage II with bulky disease, B-symptoms, elevated erythrocyte sedimentation rate, or hilar adenopathy were treated with 8 courses of C-MOPP/ABV at a single institution during a 6-year period. Radiotherapy (RT) was administered when bulky disease or residual masses were present. Endpoints of the study were response to therapy, failure free survival (FFS), overall survival (OS), and toxicity. RESULTS: Sixty-five patients (90%) received the 8 planned courses, with 49 of them (70%) receiving the full prescribed doses. After chemotherapy, 57 patients (78%) reached CR. Seven additional patients who achieved partial response (PR) reached CR after complementary radiotherapy, with an overall CR rate of 88%. The median follow-up was 31 months. Twelve patients relapsed; the 4-year FFS was 66% (95% CI, 54-78%). Two patients died during treatment because of sepsis and four due to disease progression. The 4-year OS was 92% (95% CI, 86-98%). Age > 60 years and bone marrow involvement were related to severe infectious complications. No late toxicity was reported. CONCLUSIONS: C-MOPP/ABV induces CR with acceptable toxicity in a high proportion of advanced HD patients.

Adult↗
PubMed2000

Antibodies against oncoproteins E6 and E7 of human papillomavirus types 16 and 18 in patients with head-and-neck squamous-cell carcinoma.

Human papillomaviruses (HPVs) have been recognized as an essential pathogenic factor in anogenital cancer. HPV DNA has also been found in a subgroup of head-and-neck squamous-cell carcinomas (HNSCCs), and a causative role of the virus in the development of these tumors has been suggested by the concomitant inactivation of the tumor-suppressor protein pRb. Using 4 second-generation ELISAs, we found antibodies against at least 1 of the oncoproteins E6 and E7 of the high-risk HPV types 16 and 18 in 11 of 92 sera (12%) taken from HNSCC patients at or near diagnosis, in 1 of 52 sera (2%) taken from HNSCC patients >6 months after diagnosis and in 10 of 288 sera (3. 5%) taken from sex- and age-matched healthy control individuals of the normal population. In 11 of the 12 seropositive HNSCC cases, antibodies were directed against HPV16 proteins. In patients, the HPV16 antibodies were mostly of high titer, and in 6 cases, antibodies against both HPV16 oncoproteins were present. Seven of the 8 HPV16 antibody-positive sera from the control group were of low titer, and none of the 10 antibody-positive sera reacted with both oncoproteins of the same HPV type. The HPV type of the antigens detected by the antibodies in HNSCC patients correlated well with that of the HPV DNA found in the tumor. Of 19 patients known to have HPV16 DNA-positive tumors, 7 (37%) also had HPV16 E6 and/or E7 antibodies. Our finding suggests that the antibodies were formed in an immune response against HPV E6 and E7 proteins expressed in the HNSCC and thus strongly supports the concept of a biologically active role of HPV in the development of a subgroup of HNSCC.

Adult↗
PubMed2000

Transgenic mice overexpressing alpha2A-adrenoceptors in pancreatic beta-cells show altered regulation of glucose homeostasis.

AIMS/HYPOTHESIS: To study the role of the human alpha2A-adrenoceptor in the regulation of insulin secretion and the maintenance of glucose homeostasis in transgenic mice overexpressing this receptor in pancreatic beta cells. METHODS: A human insulin promoter/human alpha2C10-adrenoceptor chimeric gene was microinjected into mouse embryos and transgenic mice were obtained. RESULTS: Analysis by RT-PCR showed that the expression of the transgene was restricted to pancreatic islets. Study of the binding of the alpha2-antagonist [3H]RX821002 to membrane preparations showed that islets from transgenic mice had ninefold higher alpha2-adrenoceptor density than those from controls. Immunohistological analysis showed, however, no change in the number or size of islets between control and transgenic mice. Transgenic animals had normal glycaemia and insulinaemia in basal conditions but greater hyperglycaemic and hypoinsulinaemic responses after injection of the alpha2-agonist, UK14304. The lower blood insulin concentration detected in transgenic mice was a reflection of a stronger inhibitory effect of the alpha2-agonist on glucose-stimulated insulin secretion in transgenic islets than in controls. Furthermore, transgenic mice did not have lower glycaemia to basal values after an intraperitoneal glucose tolerance test. This defect was abolished by treatment with the alpha2-adrenoceptor antagonist, RX821002. CONCLUSION/INTERPRETATION: These results provide evidence in vivo that overexpression of alpha2-adrenoceptors in beta cells can lead to impaired insulin secretion and glucose intolerance.

Adrenergic alpha-Agonists↗
PubMed2000

Anti-inflammatory action of type I interferons deduced from mice expressing interferon beta.

Type I interferons (IFN) are widely used for the therapeutic treatment of viral infections, tumor growth and various chronic diseases such as multiple sclerosis. Antagonism between type I IFNs and IFN-gamma has been described in cells of the immune system, in particular in the activation of macrophages. To study the systemic effects of type I IFNs we used transgenic mice carrying a human IFN-beta (hIFN-beta) gene under the control of the rat insulin I promoter. These animals expressed high levels of hIFN-beta in beta-pancreatic cells, and the ability of the macrophages to respond to pro-inflammatory stimuli was analyzed. Transgenic mice exhibited an increased extravasation of cells to the peritoneal cavity after eliciting with thioglycollate broth. The expression of the inducible form of nitric oxide synthase and cyclooxygenase-2, two enzymes involved in inflammation, was impaired in transgenic animals challenged with lipopolysaccharide and IFN-gamma. Analysis of the mechanisms leading to this attenuated inflammatory response showed a decrease in the serum levels of TNF-alpha and an inhibition of the activation of the transcription factor NF-KB in various tissues. These results indicate that systemic administration of IFN-beta might influence the response to pro-inflammatory stimuli, in particular through the antagonism of IFN-gamma signaling.

Animals↗
PubMed2000

Transgenic mice overexpressing insulin-like growth factor-II in beta cells develop type 2 diabetes.

During embryonic development, insulin-like growth factor-II (IGF-II) participates in the regulation of islet growth and differentiation. We generated transgenic mice (C57BL6/SJL) expressing IGF-II in beta cells under control of the rat Insulin I promoter in order to study the role of islet hyperplasia and hyperinsulinemia in the development of type 2 diabetes. In contrast to islets from control mice, islets from transgenic mice displayed high levels of IGF-II mRNA and protein. Pancreases from transgenic mice showed an increase in beta-cell mass (about 3-fold) and in insulin mRNA levels. However, the organization of cells within transgenic islets was disrupted, with glucagon-producing cells randomly distributed throughout the core. We also observed enhanced glucose-stimulated insulin secretion and glucose utilization in islets from transgenic mice. These mice displayed hyperinsulinemia, mild hyperglycemia, and altered glucose and insulin tolerance tests, and about 30% of these animals developed overt diabetes when fed a high-fat diet. Furthermore, transgenic mice obtained from the N1 backcross to C57KsJ mice showed high islet hyperplasia and insulin resistance, but they also developed fatty liver and obesity. These results indicate that local overexpression of IGF-II in islets might lead to type 2 diabetes and that islet hyperplasia and hypersecretion of insulin might occur early in the pathogenesis of this disease.

Animals↗
PubMed1999

Increased number of chromosomal imbalances and high-level DNA amplifications in mantle cell lymphoma are associated with blastoid variants.

Mantle cell lymphomas (MCLs) are characterized by 11q13 chromosomal translocations and cyclin D1 overexpression. The secondary genetic and molecular events involved in the progression of these tumors are not well known. In this study, we have analyzed 45 MCLs (32 typical and 13 blastoid variants) by comparative genomic hybridization (CGH). To identify the possible genes included in the abnormal chromosome regions, selected cases were analyzed for P53, P16(INK4a), RB, C-MYC, N-MYC, BCL2, BCL6, CDK4, and BMI-1 gene alterations. The most frequent imbalances detected by CGH were gains of chromosomes 3q (49%), 7p (27%), 8q (22%), 12q (20%), 18q (18%), and 9q34 (16%) and losses of chromosomes 13 (44%), 6q (27%), 1p (24%), 11q14-q23 (22%), 10p14-p15 (18%), 17p (16%), and 9p (16%). High-level DNA amplifications were identified in 11 different regions of the genome, predominantly in 3q27-q29 (13%), 18q23 (9%), and Xq28 (7%). The CGH analysis allowed the identification of regional consensus areas in most of the frequently involved chromosomes. Chromosome gains (P =. 02) and losses (P =.01) and DNA amplifications (P =.015) were significantly higher in blastoid variants. The significant differences between blastoid and typical tumors were gains of 3q, 7p, and 12q, and losses of 17p. CGH losses of 17p correlated with P53 gene deletions and mutations. Similarly, gains of 12q and high-level DNA amplifications of 10p12-p13 were associated with CDK4 and BMI-1 gene amplifications, respectively. One of 2 cases with 8q24 amplification showed C-MYC amplification by Southern blot. Alterations in 2p, 3q, 13, and 18q were not associated with N-MYC, BCL6, RB, or BCL2 alterations, respectively, suggesting that other genes may be the targets of these genetic abnormalities in MCLs. Increased number of gains (0 v 1-4 v >4 gains per case) (P =.002), gains of 3q (P =.02), gains of 12q (P =.03), and losses of 9p (P =. 003) were significantly associated with a shorter survival of the patients. These results indicate that an increased number of chromosome imbalances are associated with blastoid variants of MCLs and may have prognostic significance.

Blotting, Southern↗
PubMed1999

Insulin production by engineered muscle cells.

Type 1 diabetic patients depend dramatically on insulin replacement therapy, which involves the administration of intermediate- or long-acting insulin, together with short-acting insulin to mimic physiological insulin profiles. However, the delayed-action preparations available are not generally able to produce smooth background levels of insulin. Muscle cells were tested for long-term delivery of active human insulin as an approach to achieve a constant basal level of insulin. Thus, C2C12 mouse myoblast cells were stably transfected with a chimeric gene obtained by linking the myosin-light chain 1 (MLC1) promoter to the human proinsulin gene, containing genetically engineered furin endoprotease cleavage sites (MLC1/Insm). When differentiated, C2C12Insm myotube cells expressed high levels of insulin mRNA and protein, whereas no insulin was detected in myoblast cells. HPLC fractionation of culture medium and cell extracts from differentiated C2C12Insm cells revealed that about 90% of the proinsulin was processed to mature insulin. In addition, these cells released significant levels (about 100 microU/10(6) cells/hr) of mature insulin to the medium. The hormone was biologically active since it increased glucose consumption and utilization by the differentiated C2C12Insm cells and was able to block the expression of the endogenous phosphoenolpyruvate carboxykinase (PEPCK) gene in FTO-2B rat hepatoma cells. Furthermore, when C2C12Insm myoblast cells were transplanted into diabetic mice an increase in insulinemia and a decrease in hyperglycemia were observed. Thus, our results suggest that the use of engineered myotube cells continuously secreting a defined level of insulin might be a useful approach to improve the efficacy of insulin injection treatment.

Animals↗
PubMed1999

[Non-gastric mucosa-associated lymphoid tissue (MALT) lymphomas: analysis of 14 patients].

BACKGROUND: Mucosa-associated lymphoid tissue (MALT) lymphomas are a well defined group of B-cell non-Hodgkin's lymphomas, that arise in a wide variety of extranodal sites, most frequently in the stomach and related to Helicobacter pylori infection. The aim of the present study was to analyze the presenting features, natural history and outcome in 14 patients with non-gastric MALT lymphoma. PATIENTS AND METHODS: The main clinical data, treatment and outcome were recorded for the 14 patients with non-gastric MALT lymphoma diagnosed at a single institution in a 12 year period. The median age was 68 years and 13 patients were females. Diagnosis was made according to the REAL classification criteria. RESULTS: The initial location was thyroid (3 patients), parotid (three), submaxilar gland (three), skin (two), Waldeyer's ring (one), breast (one), lung (one), small bowel (one), liver (one) and ovary (one). At diagnosis 3 patients had > or = 2 extranodal involved sites. Autoimmune disorders were present in 5 patients: Hashimoto's thyroiditis (three), Sjögren's syndrome (one) and both (one). Two patients had a poor performance status (ECOG > 1) and B-symptoms. Five patients (36%) were in stage IV, two of them because of bone marrow infiltration. All patients had a normal serum LDH level, and 5 had high beta 2-microglobulin level. The treatment consisted in surgical resection (2 patients), surgery and radiotherapy (one), surgery and chemotherapy (two), chemotherapy and radiotherapy (two) and chemotherapy alone (7 patients, three of them with doxorubicin-containing regimens). Twelve patients were evaluable for response. Complete response, partial response and failure rates were 75, 17 and 8%, respectively. Two of the 11 responders progressed, one of them with advanced stage disease. The actuarial 4-year disease-free survival was 77% (CI 95%: 47-100%). After a median follow-up of 3.4 years, 100% of the patients were alive. CONCLUSION: Non-gastric MALT lymphomas may be associated with autoimmune disorders, may present as disseminated disease and have a very good outcome.

Adult↗