Soluble CD137: A Potential Prognostic Biomarker in Critically Ill Patients.

T cell depletion and functional impairment are characteristics of sepsis. CD137 is a costimulatory receptor on activated T cells, while soluble CD137 (sCD137) inhibits CD137 signaling. This study found elevated sCD137 levels in the plasma of patients with systemic inflammatory response syndrome (SIRS), sepsis, or septic shock compared to healthy controls. The sCD137 levels negatively correlated with the C-reactive protein and positively with procalcitonin and interleukin-6. There was no difference in sCD137 levels based on ventilation, dialysis, or vasopressor treatment. Patients with SARS-CoV-2, Gram-positive, or Gram-negative bacterial infections had similar sCD137 levels as noninfected individuals. Notably, higher plasma sCD137 levels were observed in non-survivors compared to survivors in both the SIRS/sepsis group and the SARS-CoV-2 subgroup. In conclusion, plasma sCD137 levels are associated with severe illness and survival in critically ill patients.

Clinical, Endoscopic, and Histopathologic Observations in Gastrointestinal Amyloidosis.

BACKGROUND AND AIMS: Amyloidosis is a group of systemic disorders caused by extracellular deposition of misfolded serum proteins. Gastrointestinal (GI) involvement is associated with a higher risk of GI bleeding, especially if mucosal lesions are present. Our study aims to evaluate the frequency of GI manifestations in patients with amyloidosis, to clinically characterize these patients and to describe the endoscopic and histopathologic findings in GI amyloidosis. METHODS: A retrospective, single-center study of all patients admitted with amyloidosis and GI manifestations was conducted at a German University Hospital between July 2003 and June 2023. Clinical, endoscopic, and histopathological data was retrieved from medical records. RESULTS: Between July 2003 and June 2023, 63 patients with different types of amyloidosis were included into the study. Twenty-three (36,5%) were diagnosed with GI involvement of amyloidosis (60.9% male, median age 62 ± 18.28 years). The distribution of the types of amyloidosis were amyloid light chain (AL) at 52.5%, transthyretin (ATTR) at 21.7%, amyloid A (AA) at 13.0%, and unknown at 18%. Initial GI symptoms were present in 78.3% of the patients and included mainly diarrhea (34.8%), and abdominal pain (30.4%) Affected GI organs were primarily the colon (60,8%) and the stomach (39.1%). Endoscopic findings were ulcerations (47.8%), mucosal inflammation (43.5%), polyps (26.1%), erosions (13.0%), vascular malformation, polypoid protrusion, submucosal hematoma, erythema, metaplasia, and diverticulum. Histopathological findings included vascular wall thickening, (peri-)vascular and interstitial amyloid deposition. Gastrointestinal bleeding occurred in 39.1% of the patients. The mortality rate 5 years after diagnosis was 47.8%. CONCLUSIONS: Gastrointestinal amyloidosis can present with multiple symptoms and endoscopic findings, rendering diagnosis a challenge. Of clinical relevance, GI bleeding was a frequent event in our patient cohort. Therefore, clinicians must be aware of GI bleeding as a manifestation of amyloidosis and definite diagnosis should be achieved based on biopsy results.

Bacterial Infection of an Alveolar Echinococcus Cyst from C. perfringens Septicemia: A Case Report and Review of the Literature.

Background and Objectives: Alveolar echinococcosis (AE) is a highly variable disease able to present as structurally diverse cysts in different organs based on the host's immunological state as well as the time between diagnosis and the primary infection. Bacterial superinfections, especially with anaerobic pathogens from the Clostridiaceae genus, can further alter the radiological findings due to pneumobilia, newly formed abscess formations, and inflammatory changes. Materials and Methods: We present a case of a 71-year-old Caucasian male admitted to our intensive care unit with septic shock, pneumobilia, and a complex cyst of the liver with calcification, as shown by an initial CT. Because of the septic shock, the patient was started on broad-band antibiotics. Clostridiaceae infection was considered an important differential diagnosis due to the presence of pneumobilia observed in the initial CT, without a history of previous endoscopy. Furthermore, serology for echinococcus was positive, and blood cultures showed growth of C. perfringens. Therefore, the patient was additionally treated with albendazole. After recovery, further staging was conducted, showing complete remission of the cyst and a left-over lesion classified as Alveolar Echinococcosis Ulm Classification (AEUC) V. In summary, the patient had a pre-existing, controlled AE infection that became superinfected with C. perfringens, likely attributable to the anaerobic necrotic tissue, leading to septicemia. Results: The anaerobic tissue within the AE cyst provided an ideal medium for C. perfringens to replicate, leading to cyst infection, which subsequently caused septic shock and pneumobilia. The initial findings from CT and MRI were confounded by the superinfection, demonstrating the diagnostic challenges of AE, especially when presenting with complications. Conclusions: Diagnosing AE remains a demanding task, even with the excellent tools available through serology, coupled with CT, FDG-PET-CT, and MRI. Notably, older superinfected cysts can pose difficulties when integrated into the appropriate diagnostic context. Prompt diagnosis is critical for the accurate treatment of echinococcosis and its complications, such as bacterial superinfections. From a clinical perspective, septicemia from Clostridiaceae and infections with C. perfringens-pathogens capable of inducing pneumobilia-should be regarded as significant differential diagnoses for pneumobilia in the absence of a recent history of endoscopy.

The p53 Family of Transcription Factors Represses the Alpha- fetoprotein Gene Expression in Hepatocellular Carcinoma.

BACKGROUND: p53 deletion and mutation as well as upregulation of alpha-fetoprotein (AFP) are hallmarks of hepatocarcinogenesis. p63 and p73 belong to the family of p53-related transcription factors expressing a variety of isoforms. The expression of dominant negative (ΔN) p73 is related to the reduced survival of patients with hepatocellular carcinoma (HCC). In this study, we characterized the interaction between p53 family-dependent signaling pathways and the regulation of AFP at the gene and protein levels as essential determinants of therapeutic response and prognosis in HCC. METHODS: Putative p53-, p63- and p73-binding sites within the AFP gene were identified in silico. Hep3B cells were transfected with plasmids encoding for p53, p63 and p73 to analyze the interplay of the p53 family with AFP. AFP transcription was determined by RT-qPCR. Protein levels of AFP, p53, p63 and p73 were analyzed by Western blot. RESULTS: Underlining the importance of the crosstalk between the p53 family-dependent pathways and AFP regulation we identified eight novel putative binding sites for the members of the p53 family within the introns 1, 2, 3, 4, 7, 8, 11, and 12 of the AFP gene. Accordingly, full-length isoforms of p53, p63 and p73 efficiently downregulated AFP both on mRNA and protein level. Thus, the p53 family members were identified to be major regulators of AFP repression. Of note, p63 was characterized as a novel and p73 as the most efficient repressor of AFP. CONCLUSION: p53 mutation and upregulation of AFP are essential oncogenic events in the development of HCC. Here we show that AFP gene regulation occurs via a combined action of the p53 family members p53, p63 and p73. All three tumor suppressors reduce AFP gene and protein expression. Thus, our findings reveal a novel interaction of p53 family-dependent signaling pathways and AFP regulation at the gene and protein levels in HCC.

Simultaneous Inhibition of Mcl-1 and Bcl-2 Induces Synergistic Cell Death in Hepatocellular Carcinoma.

Despite the recent approval of new therapies, the prognosis for patients with hepatocellular carcinoma (HCC) remains poor. There is a clinical need for new highly effective therapeutic options. Here, we present a combined application of BH3-mimetics as a potential new treatment option for HCC. BH3-mimetics inhibit anti-apoptotic proteins of the BCL-2 family and, thus, trigger the intrinsic apoptosis pathway. Anti-apoptotic BCL-2 proteins such as Bcl-2 and Mcl-1 are frequently overexpressed in HCC. Therefore, we analyzed the efficacy of the two BH3-mimetics ABT-199 (Bcl-2 inhibitor) and MIK665 (Mcl-1 inhibitor) in HCC cell lines with differential expression levels of endogenous Bcl-2 and Mcl-1. While administration of one BH3-mimetic alone did not substantially trigger cell death, the combination of two inhibitors enhanced induction of the intrinsic apoptosis pathway. Both drugs acted synergistically, highlighting the effectivity of this specific BH3-mimetic combination, particularly in HCC cell lines. These results indicate the potential of combining inhibitors of the BCL-2 family as new therapeutic options in HCC.

HCC biomarkers - state of the old and outlook to future promising biomarkers and their potential in everyday clinical practice.

Hepatocellular carcinoma (HCC) is one of the most common and deadly tumors worldwide. Management of HCC depends on reliable biomarkers for screening, diagnosis, and monitoring of the disease, as well as predicting response towards therapy and safety. To date, imaging has been the established standard technique in the diagnosis and follow-up of HCC. However, imaging techniques have their limitations, especially in the early detection of HCC. Therefore, there is an urgent need for reliable, non/minimal invasive biomarkers. To date, alpha-fetoprotein (AFP) is the only serum biomarker used in clinical practice for the management of HCC. However, AFP is of relatively rather low quality in terms of specificity and sensitivity. Liquid biopsies as a source for biomarkers have become the focus of clinical research. Our review highlights alternative biomarkers derived from liquid biopsies, including circulating tumor cells, proteins, circulating nucleic acids, and exosomes, and their potential for clinical application. Using defined combinations of different biomarkers will open new perspectives for diagnosing, treating, and monitoring HCC.

SARS-CoV-2 Vaccine-Induced Immune Thrombotic Thrombocytopenia with Venous Thrombosis, Pulmonary Embolism, and Adrenal Haemorrhage: A Case Report with Literature Review.

Vaccine-induced immune thrombotic thrombocytopenia (VITT) with venous thrombosis is a rare complication of SARS-CoV-2 vaccination with ChAdOx1 (AstraZeneca) and AD26.COV2.S (Johnson & Johnson, New Brunswick, NJ, USA) associated with high mortality. At present, there are no known differences in the pathophysiology or risk factors of VITT with the AstraZeneca vaccine (ChAdOx1) compared with the Johnson & Johnson vaccine (AD26.COV2.S). Herein, we present the case of a healthy 39-year-old patient with VITT after having received the vaccine Ad26.COV2.S. Ten days after vaccination, the patient developed a deep vein thrombosis and subsequent pulmonary embolism. A computed tomography scan of the abdomen showed adrenal gland bleeding and an adrenocorticotrophic hormone stimulation test diagnosed adrenal insufficiency. Therapy with intravenous immunoglobulin, argatroban and hydrocortisone was initiated immediately after diagnosis. The patient left the hospital 22 days after admission with the diagnosis of adrenal insufficiency but otherwise in good health. To the best of our knowledge, five cases of VITT and adrenal bleeding have been described to date in the literature but the presented case was the first to occur after immunisation with the vaccine of Johnson & Johnson. In summary, VITT-associated adrenal dysfunction is a very rare complication of vaccination with an adenoviral vector-based COVID-19 vaccine.

Secondary hemophagocytic lymphohistiocytosis and severe liver injury induced by hepatic SARS-CoV-2 infection unmasking Wilson's disease: Balancing immunosuppression.

A 21-year-old woman was hospitalized due to coronavirus disease 2019 (COVID-19)-associated respiratory and hepatic impairment concomitant with severe hemolytic anemia. Upon diagnosis of secondary hemophagocytic lymphohistiocytosis, immunosuppression with anakinra and steroids was started, leading to a hepatic severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) infection and viremia. Subsequent liver biopsy revealed virus particles in hepatocytes by electron microscopy and SARS-CoV-2 virus could be isolated and cultured. Immunosuppression was stopped and convalescent donor plasma given. In the differential diagnosis, an acute crisis of Wilson's disease was raised by laboratory and genetic testing. This case highlights the complexity of balancing immunosuppression to control hyperinflammation versus systemic SARS-CoV-2 dissemination.

Definition, reasons, and risk factors for mortality of patients listed for liver transplantation - a single-center study.

BACKGROUND: In Germany, following the principle "sickest first", patients awaiting liver transplantation (LTPL) are often transplanted with high MELD score and run the risk that they can no longer be transplanted, getting "too sick for transplant". METHODS: In a retrospective single-center study, we analyzed the mortality of adult patients on the waiting list for LTPL during the years 2014 to 2017. To stratify risk factors, we compared characteristics of deceased and transplanted patients. RESULTS: The main reasons for mortality were sepsis (42.9 %), malignancy (24.3 %) and bleeding (10.0 %). Risk factors for mortality (OR, univariate logistic regression, p < 0.05) were acute on chronic liver failure (ACLF), loss of E-MELD, sepsis, pneumonia, proof of pathogens, candidemia, stay at ICU, multiple organ failure and mechanical ventilation. Multivariate analysis revealed pneumonia (p < 0.001) and high MELD (p = 0.031) as risk factors. Transplantation was more likely in patients with E-MELD. We suggest a Waiting List Mortality Index for Transplantation (WMIT), by dividing deceased patients to transplanted patients to assess mortality. Average WMIT in our cohort was 0.65. CONCLUSIONS: Mortality on the waiting list is mainly determined by pneumonia and infections in high-MELD patients. Therefore, patients with ACLF after infections should be prioritized for LTPL. A WMIT might suitably represent waiting list mortality.

Consolidation cetuximab after concurrent triplet radiochemotherapy+cetuximab in patients with advanced head and neck cancer: A randomized phase II study.

BACKGROUND AND PURPOSE: Preclinical data suggest that cetuximab should be continued after end of concurrent radiotherapy+cetuximab due to its efficacy against residual tumor cells in the irradiated tumor bed. Based on this concept the phase II add-on cetuximab (AOC) study was designed. MATERIALS AND METHODS: Altogether 63 patients with advanced head and neck cancer were treated with radiochemotherapy (70 Gy, cisplatin 40 mg/m2 weekly) in combination with concurrent cetuximab (loading dose 400 mg/m2, then 250 mg/m2 weekly). Thereafter patients were randomized to cetuximab consolidation (500 mg/m2 biweekly × 6) or no further treatment. The primary endpoint was the 2-year locoregional control (LRC) rate. As translational research endpoints serum markers were analyzed before and during treatment and CT-based quantitative image analysis (radiomics) was performed. RESULTS: Median follow-up was 24 months. The 2-year LRC rates were 67.9% and 67.7% in the treatment arms with and without consolidation cetuximab, respectively. Higher than median levels of three serum markers were negatively associated with the 2-year LRC rate in the overall patient cohort: Osteopontin, IL8 and FasL2 (p ≤ 0.05). A radiomics model consisting of two radiomics features could be built showing that higher entropy and higher complexity of tumor Hounsfield unit distribution indicates worse LRC (concordance index 0.66). No correlation was found between biological and imaging markers. CONCLUSIONS: There was no evidence that consolidation cetuximab would improve the 2-year LRC rate. Prognostic biological and imaging markers could be identified for the overall patient cohort. Studies with larger patient numbers are needed to correlate biological and imaging markers.

Does airway intervention before primary nonsurgical therapy for T3/T4 laryngeal squamous cell carcinoma impact on oncological or functional outcomes?

QUESTIONS UNDER STUDY: Even today, some patients with laryngeal cancer present with airway obstruction necessitating an intervention in the form of either a tracheostomy or transoral laser debulking (TOL). Controversy exists as to whether such an intervention is a risk factor for poor oncological or functional outcome in patients who then undergo primary (chemo)radiotherapy. METHODS: Retrospective chart review of all patients undergoing primary curative nonsurgical treatment for T3/T4 laryngeal squamous cell cancer at the University Hospital Zurich between 1981 and 2011. RESULTS: A total of 29/114 patients had an airway intervention before initiation of (chemo)radiotherapy (21/29 tracheostomies, 8/29 TOL). Kaplan-Meier analysis showed no statistical difference in oncological outcomes between the groups with and without intervention (5 year overall survival: 52% vs 70%, disease specific survival: 73% vs 79%, recurrence free survival: 53% vs 63%). In functional terms, we report an overall functional larynx rate of 60%. CONCLUSIONS: Airway intervention was not found to be a risk factor for poor oncological or functional outcome in this patient group.

Radiation-induced lower cranial nerve palsy in patients with head and neck carcinoma.

Radiation-induced cranial nerve palsy (RICNP) is a severe long-term complication in patients with head and neck cancer following high-dose radiation therapy (RT). We present the case report of a patient with bilateral RICNP of the hypoglossal and vagus cranial nerves (XII/X) following postoperative RT in the era prior to the introduction of intensity-modulated RT (IMRT), and an analysis of our IMRT patient cohort at risk including the case of a XII RICNP. A total of 201 patients whose glosso-pharyngeal (IX), X and XII cranial nerves had been exposed to >65 Gy definitive IMRT in our institution between January, 2002 and December, 2012 with or without systemic therapy, were retrospectively identified. A total of 151 patients out of 201 fulfilling the following criteria were included in the analysis: Locoregionally controlled disease, with a follow-up (FU) of >24 months and >65 Gy exposure of the nerves of interest. So far, one of the assessed 151 IMRT patients at risk exhibited symptoms of RICNP after 6 years. The mean/median FU of the entire cohort was 71/68 months (range, 27-145). The results were compared with literature reports. In conclusion, RICNP appears to be a rare complication. However, a longer FU and a larger sample size are required to draw reliable conclusions on the incidence of RICNP in the era of IMRT.

Airway management in head and neck cancer patients undergoing microvascular free tissue transfer: delayed extubation as an alternative to routine tracheotomy.

QUESTIONS UNDER STUDY: The aim of this study was to evaluate two practices of airway management in patients undergoing head and neck cancer (HNC) resection and microvascular free tissue transfer (MFTT), and to assess the advantages and disadvantages of the two approaches. METHODS: Patients undergoing a delayed extubation approach (NO-TRACH group) and patients undergoing primary tracheotomy (PRIM-TRACH group) were retrospectively evaluated in terms of perioperative and postoperative outcome measures. RESULTS: Not performing routine tracheotomy was safe and no perioperative airway complications occurred. NO-TRACH patients were extubated after 1.1 ± 0.9 days (mean ± standard deviation) and secondary tracheotomy was necessary in three patients (13%). NO-TRACH patients revealed decreased duration of surgery (p <0.05) and showed trends to earlier resumption of oral feeding and decreased length of hospitalisation. Flap complication rates were similar in both groups, with an overall flap survival rate of 97.5% (n = 39/40). CONCLUSIONS: With appropriate postoperative care, carefully selected patients undergoing major HNC resections with MFTT can be safely managed without routine tracheotomy.

Late term tolerance in head neck cancer patients irradiated in the IMRT era.

BACKGROUND: The aim was to quantify severe transient and persisting late term effects in our single institution head neck cancer (HNC) cohort treated with curatively intended intensity modulated radiation therapy (IMRT). Hypothesis was if a 2-year follow up (FU) is sufficient to estimate the long term tolerance in HNC irradiated in the IMRT era. METHODS: Between 01/2002-8/2012, 707/1211 (58%) consecutively treated IMRT patients met the inclusion criteria of a FU time >12 months and loco-regional disease control (LRC). 45% presented with loco-regionally advanced disease; 55% were referred for curative definitive IMRT (66 Gy-72 Gy in 30-35 fractions), 45% underwent postoperative IMRT (60-66 Gy in 30-33 fractions). Systemic concomitant therapy was administered in 85%. Highly consistent treatment procedures were performed with respect to contouring processes, dose constraints, radiation schedules, and the use of systemic therapy. Grade 3/4 late term effects were prospectively assessed and analyzed with respect to subgroups at particular risk for specific late effects. RESULTS: Mean/median FU of the cohort was 41/35 months (15-124). 13% of the patients (92/707) experienced any grade 3/4 late effects (101 events in 92/707 patients), 81% in the first 12 months after radiation. 4% of all developed persisting late grade 3/4 effects (25 events in 25/707 patients). CONCLUSIONS: IMRT led to a high late term tolerance in loco-regionally disease free HNC patients. The onset of any G3/4 effects showed a plateau at 2 years. The question of the cervical vessel tolerance in disease free long time survivors is still open and currently under evaluation at our institution.

Multifocal adult rhabdomyoma of the head and neck manifestation in 7 locations and review of the literature.

Background. Adult rhabdomyoma is a rare benign tumour with the differentiation of striated muscle tissue, which mainly occurs in the head and neck region. Twenty-six cases of multifocal adult rhabdomyoma are documented in the literature. Method. We report a 55-year-old male with simultaneous diagnosis of 7 adult rhabdomyomas and review the literature of multifocal adult rhabdomyoma. Result. Review of the literature revealed 26 cases of multifocal adult rhabdomyoma, of which only 7 presented with more than 2 lesions. Mean age at diagnosis was 65 years with a male to female ratio of 5.5 : 1. Common localizations were the parapharyngeal space (36%), larynx (15%), submandibular (14%), paratracheal region (12%), tongue (11%), and floor of mouth (9%). Besides the known radiological features of adult rhabdomyoma, our case showed FDG-uptake in (18) F-FDG PET/CT. Conclusion. This is the first case of multifocal adult rhabdomyoma published, with as many as 7 simultaneous adult rhabdomyomas of the head and neck.

Quality of life of oropharyngeal cancer patients with respect to treatment strategy and p16-positivity.

OBJECTIVES/HYPOTHESIS: To assess the quality of life in long-term survivors with oropharyngeal cancer (OPSCC), compare the results with our historic cohort in relation to the radiation technique, and explore the influence of treatment strategy and p16 expression on quality of life (QoL). STUDY DESIGN: Retrospective chart analysis and patient response to EORTC QLQ-C30 and EORTC QLQ-H&N35 survey questionnaires. METHODS: 98/120 (82%) survivors treated by primary intensity modulated chemoradiation (n = 55), or surgery with (n = 30) or without (n = 13) adjuvant radiotherapy (RT), completed and returned the questionnaires. RESULTS: Surgically treated patients complained about significantly less troubles with dry mouth and teeth compared to the nonsurgically treated group. Comparing patients treated with surgery alone and those receiving any kind of RT (primary or adjuvant) the latter group complained about significantly more problems. Patients with p16-positive tumors demonstrated significantly higher tumor stages, but significantly better scores in physical and role functions. CONCLUSIONS: Early disease can be treated with high long-term QoL by surgery alone. Primary surgery with postoperative RT in selected patients with limited primary tumors and advanced neck disease renders excellent QoL. Our results suggest that IMRT is superior to former radiation techniques with regard to QoL, and should be considered as standard of care in patients undergoing RT for OPSCC. Patients with p16 positive tumors appear to show not only a better outcome but also report on a better QoL.

Follow up after IMRT in oral cavity cancer: update.

PURPOSE: Except for early stages (T1/2 N0), the prognosis for patients with oral cavity cancer (OCC) is known to be worse than for those with pharyngeal carcinoma. While definitive intensity modulated radiation therapy (IMRT)-chemotherapy affords loco-regional control rates (LRC) of approximately 80% in advanced pharyngeal cancer, corresponding rates are reported to be much lower for OCC. The aim of this work was to evaluate loco-regional disease control and overall survival (OAS) in a relatively large OCC patient cohort treated in the IMRT era. METHODS AND MATERIALS: Between October 2002 and June 2011, 160 OCC patients were treated with curative intention IMRT at our department. 122 patients (76%) were referred with primary disease and 38 patients (24%) with a recurrent OCC at least 3 months after surgery alone. Definitive IMRT was performed in 44/160 patients (28%), whilst 116 patients underwent previous surgery. Simultaneous systemic therapy was administered in 72%. RESULTS: Patients with postoperative IMRT (+/-systemic therapy) with R0-1 status (n = 99) reached significantly higher LRC/OAS rates than patients following IMRT for macroscopic disease (n = 61), with 84%/80% versus 38%/33% at 3 years, respectively (p < 0.0001). This was found in patients treated for initial, as well as recurrent, disease. Less than 2% persisting grade 3/4 late effects were observed. CONCLUSIONS: IMRT for R0-1 situations translated into a highly significant superior LRC and OAS compared to the IMRT cohort treated for macroscopic disease. Treatment was well tolerated.

Auxin-dependent cell cycle reactivation through transcriptional regulation of Arabidopsis E2Fa by lateral organ boundary proteins.

Multicellular organisms depend on cell production, cell fate specification, and correct patterning to shape their adult body. In plants, auxin plays a prominent role in the timely coordination of these different cellular processes. A well-studied example is lateral root initiation, in which auxin triggers founder cell specification and cell cycle activation of xylem pole-positioned pericycle cells. Here, we report that the E2Fa transcription factor of Arabidopsis thaliana is an essential component that regulates the asymmetric cell division marking lateral root initiation. Moreover, we demonstrate that E2Fa expression is regulated by the LATERAL ORGAN BOUNDARY DOMAIN18/LATERAL ORGAN BOUNDARY DOMAIN33 (LBD18/LBD33) dimer that is, in turn, regulated by the auxin signaling pathway. LBD18/LBD33 mediates lateral root organogenesis through E2Fa transcriptional activation, whereas E2Fa expression under control of the LBD18 promoter eliminates the need for LBD18. Besides lateral root initiation, vascular patterning is disrupted in E2Fa knockout plants, similarly as it is affected in auxin signaling and lbd mutants, indicating that the transcriptional induction of E2Fa through LBDs represents a general mechanism for auxin-dependent cell cycle activation. Our data illustrate how a conserved mechanism driving cell cycle entry has been adapted evolutionarily to connect auxin signaling with control of processes determining plant architecture.

Characterization and modulation of fibroblast/endothelial cell co-cultures for the in vitro preformation of three-dimensional tubular networks.

Various assays of different complexity are used in research on angiogenesis in health and disease. The results of these assays increasingly impact the field of tissue engineering because preformed microvascular networks may connect and conduct to the vascular system of the host, thereby helping us to support the survival of implanted cells and tissue constructs. An interesting model that supports the formation of EC (endothelial cells) tubular structures in vitro is based on co-culturing them with fibroblasts. Our initial multilayer approach was recently transferred into a three-dimensional spheroid model using HUVEC (human umbilical vein endothelial cells) as model cells. The aim of the present study is to further characterize, extend and validate this fibroblast/EC spheroid co-culture system. We have evaluated the model with a maximum size of 600-650 µm attained on day 3 from inoculation of 4×104 fibroblasts with 1×104 EC. Cell count and spheroid diameter significantly decreased as a function of time, but the EC network that developed over a period of 14 days in culture was clearly visible and viable, and central cell death was excluded. We successfully included HMVEC (human microvascular endothelial cells) of dermal origin in the system and replaced FBS (fetal bovine serum) with human AB serum, which positively impacted the EC network formation at optimized concentrations. The need for exogenous growth factors [VEGF (vascular endothelial growth factor), EGF (epithelial growth factor), bFGF (basic fibroblast growth factor) and IGF-1 (insulin-like growth factor-1)] routinely added to classical EC media was also assessed. The behaviour of both fibroblasts and EC in response to a combination of these exogenous growth factors differed critically in fibroblast/EC spheroid co-cultures compared with the same cells in the multilayer approach. VEGF was the most relevant exogenous factor for EC network formation in fibroblast/EC multilayers, but was ineffective in the spheroid system. IGF-1 was found, in general, to be dispensable; however, while it had a negative impact on EC networking in the presence of bFGF and EGF in the multilayer, it did not in the spheroid approach. We conclude that the critical determinants of EC network formation and cell survival are not universal, but have to be specifically optimized for each culture model.

[A 37-year-old patient with fever, dyspnea and elevated transaminases after a stay in Mexico]. / 37-jähriger Patient mit Fieber, Dyspnoe und erhöhten Transaminasen nach Mexikoaufenthalt.

CASE REPORT: A 37-year-old patient with cephalgia and fever after his return from Mexico is reported. Due to persistently elevated transaminases, a liver biopsy was performed. Histological examination revealed hepatic involvement of a granulomatous disease. Serologic analyses detected anti-Brucella IgM. The suspected diagnosis was thus brucellosis taking the typical anamnesis into account. Treatment with rifampicin and doxycycline led to a complete convalescence of the patient. CONCLUSION: Brucellosis is an anthropozoonosis that exists worldwide. Potential sources of infection are uncooked or unpasteurized milk and milk products of infected animals. Complete cure of most brucellosis-infected patients can be achieved by an early and adequate antibiotic treatment.