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Frank Weber

Publications and source records attributed to Frank Weber.

At least 19 recordsLinked to original sources
PubMed2026

Transcriptomic analysis of eggs, rediae and cercariae reveal stage-specific adaptations in the rumen fluke Calicophoron daubneyi.

Rumen flukes, particularly the trematode Calicophoron daubneyi, are emerging parasites of livestock in Europe, yet transcriptomic insights into their environmental and intermediate host stages remain limited. Here, we present a comprehensive transcriptomic analysis of eggs at three distinct developmental stages (freshly excreted, early developmental and eye-spot stages), as well as rediae and cercariae, of C. daubneyi. High-quality RNA-sequencing (RNA-seq) datasets revealed both shared and stage-specific transcriptional profiles with each developmental stage exhibiting its own distinct expression pattern. Subsequent GO-Term enrichment analyses revealed that fully embryonated eggs in eye-spot-stage especially upregulated genes related to cilia assembly, movement and motility, reflecting preparation for miracidial hatching and host-seeking behavior. Rediae showed enhanced transcription of genes involved in diverse metabolic and biosynthetic processes, supporting rapid asexual proliferation within the snail intermediate host. Cercariae exhibited predominant upregulation of genes associated with signal transduction and energy metabolism, indicating the adaptation to its changing environmental conditions. These findings provide the first transcriptomic insights into the biology of C. daubneyi outside the definitive host, reveal molecular mechanisms underlying development, transmission and adaptation to a changing environment and identify stage-specific genes as potential targets for interventions aimed at disrupting the parasites life cycle and controlling rumen flukes in the future.

Animals↗
PubMed2007

Microenvironmental genomic alterations and clinicopathological behavior in head and neck squamous cell carcinoma.

CONTEXT: Carcinogens associated with head and neck squamous cell carcinoma (SCC) genesis should inflict genomic alterations not only on the epithelium but also the mesenchyme of the aerodigestive tract. Therefore, the apparently nonmalignant stroma surrounding the tumor epithelium can acquire genomic alterations and contribute to cancer initiation and progression. OBJECTIVES: To determine compartment-specific loci of loss of heterozygosity or allelic imbalance (LOH/AI) and to identify which genomic alterations restricted to the stroma cell population contribute to aggressiveness of head and neck SCC disease. DESIGN, SETTING, AND PATIENTS: Tumor epithelium and surrounding stroma were isolated from 122 US patients with oral cavity and oropharyngeal or hypopharyngeal SCC and subjected to whole-genome LOH/AI analysis using 366 microsatellite markers. Samples, collected between 2001 and 2004, were pulled and transferred in batches of 10 to 30 between 2002 and 2005. Laser capture microdissection DNA extraction and technical genotyping occurred on a rolling model between 2002 and November 2005. MAIN OUTCOME MEASURES: Compartment-specific frequency and distribution of LOH/AI were determined, and hot spots of genomic alterations identified. Compartment-specific LOH/AI events were correlated with presenting clinicopathologic characteristics. RESULTS: Tumor-associated stroma of head and neck SCC from smokers were found to have a high degree of genomic alterations. A correlation between tumor aggressiveness could be found for a specific set of 5 loci. Three stroma-specific loci (D4S2417, D3S360, and D19555) were associated with tumor size (pT) and regional nodal metastases (pN). Furthermore, 2 epithelial-specific LOH/AI hot spots were positively correlated with pN status and clinical stage. CONCLUSIONS: Stroma-specific genetic alterations are associated with smoking-related head and neck SCC genesis. These findings suggest novel prognostic or diagnostic biomarkers and identify potential new molecular targets for therapeutic and preventive intervention.

Aged↗
PubMed2006

Mapping geographic zones of cancer risk with epigenetic biomarkers in normal breast tissue.

PURPOSE: Genetic alterations were previously identified in normal epithelia adjacent to invasive cancers. The aim of this study was to determine DNA methylation in histologically normal tissues from multiple geographic zones adjacent to primary breast tumors. EXPERIMENTAL DESIGN: First, methylation status of a 4-kb region of RASSF1A promoter was interrogated using oligonucleotide-based microarray in 144 samples (primary tumors, 47; adjacent normals, 69; reduction mammoplasty tissues, 28). Second, allelic imbalance (AI)/loss of heterozygosity (LOH) surrounding RASSF1A promoter were analyzed in 30 samples (tumors, 8; adjacent normals, 22). Third, global methylation screening of 49 samples (tumors, 12; adjacent normals, 25; reduction mammoplasty, 12) was done by differential methylation hybridization. Real-time quantitative methylation-specific PCR was used to validate the microarray findings. RESULTS: DNA methylation in the core RASSF1A promoter was low in reduction mammoplasty tissues (P=0.0001) when compared with primary tumors. The adjacent normals had an intermediate level of methylation. The regions surrounding the core were highly methylated in all sample types. Microsatellite markers showed AI/LOH in tumors and some of the adjacent normals. Concurrent AI/LOH and DNA methylation in RASSF1A promoter occurred in two of six tumors. Global methylation screening uncovered genes more methylated in adjacent normals than in reduction mammoplasty tissues. The methylation status of four genes was confirmed by quantitative methylation-specific PCR. CONCLUSIONS: Our findings suggest a field of methylation changes extending as far as 4 cm from primary tumors. These frequent alterations may explain why normal tissues are at risk for local recurrence and are useful in disease prognostication.

Allelic Imbalance↗
PubMed2006

Glatiramer acetate-specific human CD8(+) T cells: increased IL-4 production in multiple sclerosis is reduced by glatiramer acetate treatment.

Glatiramer acetate (GA) is an approved drug for therapy of relapsing remitting MS that acts as a T cell antigen. Here, we report the cloning of HLA restricted, GA-specific human CD8(+) T cells. In addition, we analyzed the cytokine profile of GA-reactive CD8(+) T cell lines. Unexpectedly, IL-4 was increased in untreated MS patients as compared to healthy individuals (p<0.001). In GA-treated patients, however, IL-4 (p<0.001), IL-10 (p<0.001) and TNF-alpha (p<0.001) were decreased. Thus, while GA is known to induce a TH2 bias in CD4(+) T cells, we detected a distinct pattern in GA-reactive CD8(+) T cells.

Adult↗
PubMed2006

Oxytocin does not contribute to the effects of cervical dilation on progesterone secretion and embryonic development in mares.

The aim of the present study was, to investigate the effects of oxytocin administration on Day 7 post-ovulation on progesterone secretion, pregnancy rate and embryonic growth in mares. Endogenous stimulation of oxytocin release was compared to the administration of native oxytocin or the long-acting oxytocin analogue carbetocin. At Day 7 after ovulation, mares had to undergo four treatments in a crossover design: (a) control, (b) oxytocin (10 IU i.v.), (c) carbetocin (280 microg i.m.) and (d) cervical dilation. On Day 13, all mares (8 of 8 mares) were pregnant on groups control, oxytocin and carbetocin and only 6 of 8 mares on group dilation. In one mare uterine fluid accumulation and uterine edema from Day 6 to 13 and early embryonic death by Day 11 occurred during dilation treatment. Another mare, which did not become pregnant during dilation treatment, developed uterine fluid accumulation and uterine edema from Day 10 to 14. Mean growth rates of the conceptuses did not differ among treatment groups and individual growth rates varied in a wide range from -0.1 to 0.8 cm per day. At Day 13, mean diameters of conceptuses yielded 1.4+/-0.1 cm in control group, 1.5+/-0.1 in oxytocin and carbetocin group and 1.3+/-0.2 cm in dilation group. Secretion of progesterone was not affected by treatments. Administration of oxytocin and carbetocin caused similar maximum plasma concentrations of oxytocin, but onset and duration of peaks differed. Maximum concentrations after intramuscular application of carbetocin were obtained almost 20 min later when compared to intravenous administration of oxytocin. Duration of peaks after injection of the long-acting oxytocin analogue was more than three-fold longer than after administration of native oxytocin. In conclusion, the present study showed that single administration of oxytocin or its long-acting analogue carbetocin at Day 7 after ovulation did not affect progesterone secretion, pregnancy rate and embryonic growth. Two possible scenarios concerning the effects of cervical dilation were observed: In the majority of mares, dilation of the caudal half to two-third of the cervical lumen up to a diameter of 4.5 cm had no negative consequences on progesterone secretion and pregnancy outcome. However, cervical dilation caused uterine inflammation and subsequent luteolysis in two mares and early embryonic death in one of them. Thus, manipulation of the cervix itself seems not to have negative impact on success rates of transcervical transfer of embryos in the mare.

Animals↗
PubMed2006

Acute and long-term results of bifurcation stenting (from the Coroflex Registry).

Angioplasty of bifurcation lesions represents a continuing challenge. A total of 421 consecutive patients were prospectively followed in a registry on bifurcation stenting with a high-end bare metal stent (Coroflex, BBraun, Berlin, Germany), allowing side branch percutaneous transluminal coronary angioplasty through the stent struts without distraction of the main vessel stent from the vessel wall or other distortions. This approach obviated the 2-wire technique and kissing balloons. Detailed data, including lesion location, stenosis morphology, procedural success, and hospital and follow-up major adverse cardiac events (MACEs; acute myocardial infarction, death, revascularization, hospitalization due to angina), were collected from 6 European centers. Of the patients, 60% had stable angina, 23% had unstable angina pectoris/non-ST-elevation myocardial infarction, and 17% had ST-elevation myocardial infarction. In 17% of patients, the main vessel alone was stented; in 71%, stenting of the main vessel was complemented by side branch percutaneous transluminal coronary angioplasty. Technical success (residual stenosis <50%) in the 2 branches was achieved in 90% (main vessel in 99%). The rate of MACEs at discharge was 2%. After 6 months, 17% of patients had undergone target lesion revascularization or coronary artery bypass grafting. The total 6-month MACE rate was 22%. In conclusion, successful bifurcation stenting with a low MACE rate is possible in most patients using a simplified approach with a dedicated high-end bare metal stent.

Adult↗
PubMed2006

A limited set of human MicroRNA is deregulated in follicular thyroid carcinoma.

CONTEXT: Although the pathogenesis of follicular thyroid carcinoma (FTC) and its relation to follicular adenoma (FA) remains unclear, detailed understanding of FTC carcinogenesis would facilitate addressing the scientific and clinical challenges, given that there are morphological and molecular similarities between FTC and the frequently occurring FA. Micro-RNAs (miRNAs) are a new class of small, noncoding RNAs implicated in development and cancer and may lend novel clues to FTC genesis. For the latter process, a deregulated miRNA can orchestrate the aberrant expression of several hundred target genes. OBJECTIVE: The objective of the study was to identify deregulated miRNAs in FTC. DESIGN: We used two high-density expression arrays to identify miRNAs and their target genes that are differentially expressed between FTC and FA. Validation was done by quantitative RT-PCR. We further functionally characterized the effect of deregulated miRNAs in vitro using HEK293T, FTC133, and K5 cell lines. PATIENTS: In total, 45 primary thyroid samples (23 FTC, 20 FA, four normal control thyroid) were analyzed. RESULTS: Two specific miRNAs, miR-197 and miR-346, were significantly overexpressed in FTC. In vitro overexpression of either miRNA induced proliferation, whereas inhibition led to growth arrest. Overexpression of miR-197 and miR-346 repressed the expression of their predicted target genes in vitro and in vivo. CONCLUSIONS: Our observations show that miR-197 and miR-346 contribute to FTC carcinogenesis. Both miRNAs and their target genes might potentially provide for novel molecular markers and act as novel targets for treatment by interference, which could potentially normalize the deregulated profile of many downstream target genes.

Adenocarcinoma, Follicular↗
PubMed2006

Monthly intravenous methylprednisolone in relapsing-remitting multiple sclerosis - reduction of enhancing lesions, T2 lesion volume and plasma prolactin concentrations.

BACKGROUND: Intravenous methylprednisolone (IV-MP) is an established treatment for multiple sclerosis (MS) relapses, accompanied by rapid, though transient reduction of gadolinium enhancing (Gd+) lesions on brain MRI. Intermittent IV-MP, alone or with immunomodulators, has been suggested but insufficiently studied as a strategy to prevent relapses. METHODS: In an open, single-cross-over study, nine patients with relapsing-remitting MS (RR-MS) underwent cranial Gd-MRI once monthly for twelve months. From month six on, they received a single i.v.-infusion of 500 mg methylprednisolone (and oral tapering for three days) after the MRI. Primary outcome measure was the mean number of Gd+ lesions during treatment vs. baseline periods; T2 lesion volume and monthly plasma concentrations of cortisol, ACTH and prolactin were secondary outcome measures. Safety was assessed clinically, by routine laboratory and bone mineral density measurements. Soluble immune parameters (sTNF-RI, sTNF-RII, IL1-ra and sVCAM-1) and neuroendocrine tests (ACTH test, combined dexamethasone/CRH test) were additionally analyzed. RESULTS: Comparing treatment to baseline periods, the number of Gd+ lesions/scan was reduced in eight of the nine patients, by a median of 43.8% (p = 0.013, Wilcoxon). In comparison, a pooled dataset of 83 untreated RR-MS patients from several studies, selected by the same clinical and MRI criteria, showed a non-significant decrease by a median of 14% (p = 0.32). T2 lesion volume decreased by 21% during treatment (p = 0.001). Monthly plasma prolactin showed a parallel decline (p = 0.027), with significant cross-correlation with the number of Gd+ lesions. Other hormones and immune system variables were unchanged, as were ACTH test and dexamethasone-CRH test. Treatment was well tolerated; routine laboratory and bone mineral density were unchanged. CONCLUSION: Monthly IV-MP reduces inflammatory activity and T2 lesion volume in RR-MS.

Adult↗
PubMed2006

Total-genome analysis of BRCA1/2-related invasive carcinomas of the breast identifies tumor stroma as potential landscaper for neoplastic initiation.

We have shown that the tumor microenvironment of sporadic breast cancer is diverse in genetic alterations and contributes to the cancer phenotype. The dynamic morphology of the mammary gland might be of special interest in hereditary breast/ovarian cancer syndrome (HBOC). We hypothesized that hotspots of loss of heterozygosity or allelic imbalance (LOH/AI) within the tumor stroma of BRCA1/2-related breast cancers provide an impaired mammary stroma that could facilitate later malignant transformation of the breast epithelium. We conducted a total genome LOH/AI scan of DNA derived from the epithelium and stroma of 51 BRCA1/2-related breast cancers, using 372 microsatellite markers. We compared these data with those from a set of 134 sporadic breast cancers. HBOC-related breast cancers accumulated significantly more genetic alterations than did sporadic breast cancers. BRCA1/2-related breast cancer stroma showed LOH/AI at 59.7% of all loci analyzed, similar to the average frequency of LOH/AI observed in the epithelium (66.2%). This is remarkably different from sporadic breast cancers, for which the average epithelial LOH/AI frequency (36.7%) far exceeds the average stromal LOH/AI frequency (28.4%) (P=.03). We identified 11 hotspot loci of LOH/AI in the BRCA1/2 stroma, encompassing genes such as POLD1, which functions in DNA replication, and SDHB. In a subset of samples, enriched for BRCA1 cases, we found 45.0% overall LOH/AI in the stroma, which was significantly higher than the 41.8% LOH/AI observed in corresponding epithelium (P=.04). Together, our data indicate that, in HBOC-related breast cancers, the accumulation of genomic instability in the cancer stroma coincides with that in the neoplastic epithelium, and we postulate that such a genetically unstable stroma might facilitate a microenvironment that functions as a landscaper that promotes genomic instability in the epithelium and, subsequently, neoplastic transformation.

Adult↗
PubMed2006

Liver transplantation for patients with metastatic endocrine tumors: single-center experience with 15 patients.

In contrast to other secondary liver malignancy, orthotopic liver transplantation (OLT) is considered as a treatment modality for nonresectable endocrine liver metastases in selected patients. However, only few series have assessed patient selection criteria and long-term results, and no reports have focused on the impact of new technologies in this regard. Between 1992 and 2004, 28 patients with malignant endocrine tumors underwent evaluation for OLT according to our protocol. Data were entered into a prospective database. During pretransplant evaluation, somatostatin receptor scintigraphy detected extrahepatic metastases not diagnosed in standard imaging in 10 patients. Of them, 3 showed aberrant Ki67 labeling results. One patient was excluded from further evaluation due to severe carcinoid heart. Thus far, 15 patients, 10 men and 5 women, aged 37 to 67 years, were subjected to the transplant procedure (11 deceased donor OLT, 3 living donor liver transplantations, and 1 cluster transplantation). Four patients died during the hospital treatment. The median follow-up of the discharged patients was 60.8 months. The actuarial patient survival was 78.3% at 1 year and 67.2% at 5 years. The actuarial 1-, 2-, and 5-year tumor-free survival amounted to 69.4%, 48.3%, and 48.3%, respectively. Two patients underwent surgery for isolated tumor recurrence. In 2 patients, peptide receptor radiotherapy was carried out because of multilocular recurrent disease. In conclusion, liver transplantation is a realistic therapeutic option for highly selected patients with hepatic metastases of endocrine tumors. Our strategy, which implements strict pretransplant selection and aggressive surgical approach, in case of disease recurrence, in addition to systemic radiopeptide treatment, led to an excellent long-term survival cure, however, is unlikely to be achieved.

Adult↗
PubMed2006

Treatment with (90)Y- and (177)Lu-DOTATOC in patients with metastatic neuroendocrine tumors.

BACKGROUND: Treatment with (90)Y- or (177)Lu-DOTATOC has recently been introduced in the palliative treatment of somatostatin receptor-expressing neuroendocrine tumors (NETs). The aim of the study was to present clinical experience with (90)Y- and (177)Lu-DOTATOC therapy in the management of NET. METHODS: To prove suitability for treatment each patient underwent scanning with (111)In-DTPAOC or (68)Ga-DOTATOC positron emission tomography/computed tomography. All patients received [(90)Y-DOTATOC] as initial treatment. In case of disease relapse the treatment was repeated. To avoid side effects of repeated [(90)Y] applications, a switch to [(177)Lu-DOTATOC] was carried out. Clinical, biochemical, and radioimaging responses were documented. RESULTS: Twenty patients with metastatic nonresectable NETs (15 pancreas NETs, 2 midgut NETs, 1 gastrinoma, 1 paraganglioma, 1 NET of unknown primary origin) were included. In 8 patients the treatment was repeated more than once (mean, 3 times; range, 2-5 times). After [(90)Y] treatment moderate toxicity was observed in 8 patients. No serious adverse events were documentable. After restaging, a partial remission was found in 5 patients, stable disease in 11 patients, and tumor progression in 4 patients. CONCLUSIONS: Peptide receptor-targeted radionuclide therapy is a promising, safe, and feasible approach in the palliative therapy of patients with NET.

Adult↗
PubMed2006

A new pumpless extracorporeal interventional lung assist in critical hypoxemia/hypercapnia.

OBJECTIVE: Pump-driven extracorporeal gas exchange systems have been advocated in patients suffering from severe acute respiratory distress syndrome who are at risk for life-threatening hypoxemia and/or hypercapnia. This requires extended technical and staff support. DESIGN: We report retrospectively our experience with a new pumpless extracorporeal interventional lung assist (iLA) establishing an arteriovenous shunt as the driving pressure. SETTING: University hospital. PATIENTS: Ninety patients with acute respiratory distress syndrome. INTERVENTIONS: Interventional lung assist was inserted in 90 patients with acute respiratory distress syndrome. MEASUREMENTS AND MAIN RESULTS: Oxygenation improvement, carbon dioxide elimination, hemodynamic variables, and the amount of vasopressor substitution were reported before, 2 hrs after, and 24 hrs after implementation of the system. Interventional lung assist led to an acute and moderate increase in arterial oxygenation (Pao2/Fio2 ratio 2 hrs after initiation of iLA [median and interquartile range], 82 mm Hg [64-103]) compared with pre-iLA (58 mm Hg [47-78], p < .05). Oxygenation continued to improve for 24 hrs after implementation (101 mm Hg [74-142], p < .05). Hypercapnia was promptly and markedly reversed by iLA within 2 hrs (Paco2, 36 mm Hg [30-44]) in comparison with before (60 mm Hg [48-80], p < .05], which allowed a less aggressive ventilation. For hemodynamic stability, all patients received continuous norepinephrine infusion. The incidence of complications was 24.4%, mostly due to ischemia in a lower limb. Thirty-seven of 90 patients survived, creating a lower mortality rate than expected from the Sequential Organ Failure Assessment score. CONCLUSIONS: Interventional lung assist might provide a sufficient rescue measure with easy handling properties and low cost in patients with severe acute respiratory distress syndrome and persistent hypoxia/hypercapnia.

Adult↗
PubMed2006

Second messenger and Ras/MAPK signalling pathways regulate CLOCK/CYCLE-dependent transcription.

The heterodimeric complex of the transcription factors CLOCK (CLK) and CYCLE (CYC) constitutes the positive element of the circadian clock in Drosophila and mammals. Phosphorylation of clock proteins represents an essential mechanism for promotion and control of the molecular oscillator. However, the kinases and signalling pathways that regulate CLK/CYC function remain largely elusive. In the present study we performed a chemical screen of kinase inhibitors in a cell culture reporter assay to identify functional regulators of CLK/CYC-dependent gene expression. These studies and analysis of constitutively active forms of kinases revealed that cyclic nucleotide/protein kinase A (PKA), calcium/calmodulin-dependent kinase (CaMK) II and Ras/mitogen-activated protein kinase (MAPK) regulate CLK/CYC activity. In vitro phosphorylation analysis showed a direct phosphorylation of CLK by CaMK II and p42 MAPK [extracellular signal-regulated kinase (ERK) 2], suggesting that these kinases regulate CLK/CYC-dependent transcription by direct phosphorylation of CLK.

ARNTL Transcription Factors↗
PubMed2005

Incidental findings in magnetic resonance imaging of the brains of healthy young men.

BACKGROUND AND PURPOSE: To determine the frequency of serious intracranial abnormalities in a healthy young male population. METHODS: Cranial MRI of 2,536 healthy young males, mean age 20.5 years, all applicants for military flying duties in the German Air Force. RESULTS: The authors report a variety of morphological abnormalities in the brains of a large population of healthy young males, providing data on disease prevalence. Arachnoid cysts were found in 1.7% (95% CI 1.2 to 2.3%), vascular abnormalities in 0.51% (95% CI 0.29 to 0.9%), and intracranial tumors in 0.47% (95% CI 0.26 to 0.85%) of the applicants. No cerebral aneurysms were found. CONCLUSION: The prevalence of primary brain tumors seems to be higher, whereas the prevalence of intracranial aneurysms is lower than expected. Only a small percentage of the detected abnormalities require urgent medical attention.

Adolescent↗