Traumatic brain injury alters presentation of mild behavioral impairment domains across progression of all-cause dementia

Introduction

Traumatic brain injury (TBI) may alter dementia progression, although co-occurring neuropsychiatric symptoms (NPS) have received less attention. The mild behavioral impairment (MBI) construct relates NPS to underlying neural circuit disruptions, representing an important area of inquiry regarding TBI and dementia.

Objectives

(1) to examine the influence of prior TBI history (preceding study enrollment) on MBI incidence in all-cause dementia (prior to dementia diagnosis, i.e. MBI’s original definition) and (2) to utilize MBI domains as a construct for examining the influence of TBI on related NPS across the course of dementia onset and progression.

Methods

Using National Alzheimer’s Coordinating Center data, individuals progressing from normal cognition to all-cause dementia over 7.6±3.0 years were studied to estimate MBI incidence and symptom domains in 124 participants with prior TBI history compared to 822 without.

Results

Moderate-severe TBI was associated with the social inappropriateness MBI domain (OR_adj.=4.034; p=0.024) prior to dementia onset, and the abnormal perception/thought content domain looking across dementia progression (HR_adj.=3.703, p=0.005). TBI (all severities) was associated with the decreased motivation domain looking throughout dementia progression (HR_adj.=1.546, p=0.014).

Conclusions

TBI history is associated with particular MBI domains prior to onset and throughout progression of dementia. Understanding TBI’s impact on inter-related NPS may help elucidate underlying neuropathology.

Disclosure

No significant relationships.

Polysomnography Following Traumatic Brain Injury: A Systematic Review and Meta-Analysis

Introduction

Sleep disturbances are common following traumatic brain injury (TBI) worsening morbidity and other neuropsychiatric symptoms. Post-TBI alterations in sleep architecture require further study.

Objectives

(1) To evaluate polysomnographic measures of sleep architecture in participants with history of TBI compared to controls and as meta-analyses of pooled means. (2) To evaluate effects of timing and severity of TBI on polysomnographic outcomes.

Methods

PRISMA compliant systematic review was conducted of MEDLINE, PsycINFO, EMBASE and Scopus. Inclusion criteria: 1) reporting polysomnography in the context of TBI and 2) operationalizing TBI using clear/formalized criteria. Data were pooled in random-effects meta-analyses with outcomes expressed as mean differences (MD).

Results

In participants with TBI, sleep was comprised of 19.39% REM sleep, 8.13% N1, 51.18% N2, and 17.53% N3, as determined by meta-analyses of single means. Total sleep time was reduced in chronic (>6 months) TBI compared to acute-intermediate TBI (<6 months) (p=0.01). Compared to controls, participants with TBI differed with increased N1 sleep (MD=0.64%; 95%CI=0.02,1.25; p=0.04), reduced sleep efficiency (MD=-1.65%; 95%CI=-3.18,-0.12; p=0.03), and reduced sleep latency on the multiple sleep latency test (MD=-5.90mins; 95%CI=-10.09,-1.72; p<0.01). On sub-group analyses, participants with mild TBI differed from controls with reduced total sleep time (MD=-29.22mins, 95%CI=-54.16,-4.27; p=0.02). Similarly, participants with acute-intermediate TBI exhibited increased sleep latency compared to controls (MD=8.96mins; 95%CI=4.07,13.85; p<0.01) and differed significantly from participants with chronic TBI (X2(1,N=608)=6.54; p=0.01).

Conclusions

Sleep architecture is altered following TBI with potential implications regarding functional outcomes and recovery. These alterations appear to differ based on severity of injury and time since injury.

Disclosure

No significant relationships.

Surgical margin clearance and extended chemotherapy defines survival for synchronous oligometastatic liver lesions of the ductal adenocarcinoma of the pancreas

Background

The role of surgery for circumscribed synchronous hepatic lesions of the pancreatic ductal adenocarcinoma (PDAC) remains controversial. Thus, the aim of our study was to compare survival outcome (OS) after surgery of patients with hepatic metastases (M1surg) to patients with only localized disease.

Methods

Correlation analysis of clinicopathological data and OS after resection of M1surg patients and patients with localized PDACs (M0) was performed. Patients were included for survival analysis only if a complete staging including perineural, venous and lymphatic invasion was available.

Results

Out of the study collective, 35 patients received extended surgery (M1surg), whereas 131 patients received standardized surgery for localized disease (M0). Length of hospitalization and mortality was similar in both groups. FOLFIRNOX as an adjuvant treatment regime was administered in ~ 23 and ~ 8% of M1surg and M0 patients, respectively. In subgroup analysis of R0 resected patients and in multivariate analysis of the total cohort, there was no difference in overall survival between both groups. Only the resection status (R1 vs R0) and venous invasion (V1) were identified as independent prognostic factors. Site of recurrence in R0 resected M1surg patients and in M0 patients were homogenously distributed.

Conclusion

This is the first study demonstrating a survival benefit after extended surgery for synchronously hepatic-metastasized PDACs. We found no difference in survival outcome of metastasized patients when compared to patients with localized disease. FOLFIRINOX as an adjuvant treatment regime for resected M1surg presumably is worthwhile. Larger multicenter studies are still needed to validate our results.

Supplementary Information

The online version contains supplementary material available at 10.1007/s10147-021-01961-5.

Mesopancreatic excision for pancreatic ductal adenocarcinoma improves local disease control and survival

BACKGROUND

Survival in ductal adenocarcinoma of the pancreatic head (hPDAC) is poor. After implementation of the circumferential resection margin (CRM) into standard histopathological evaluation, the margin negative resection rate has drastically dropped. However, the impact of surgical radicality on survival and the influence of malignant infiltration of the mesopancreatic fat remains unclear. At our institution, a standardized dissection of the mesopancreatic lamina and peri-pancreatic vessels are obligatory components of radical pancreatoduodenectomy. The aim of our study was to histopathologically analyze mesopancreatic tumor infiltration and the influence of CRM-evaluated resection margin on relapse-free and overall survival.

METHOD

Clinicopathological and survival parameters of 264 consecutive patients who underwent surgery for hPDAC were evaluated.

RESULTS

The rate of R0 resection R0(CRM-) was 48.5%, after the implementation of CRM. Mesopancreatic fat infiltration was evident in 78.4% of all consecutively treated patients. Patients with mesopancreatic fat infiltration were prone to lymphatic metastases (N1 and N2) and had a higher rate of positive resection margin (R1/R0(CRM+)). In multivariate analysis, only R0 resection was shown to be an independent prognostic parameter. Local recurrence was diagnosed in only 21.1% and was significantly lower in patients with R0(CRM-) resected hPDACs (10.9%, p < 0.001).

CONCLUSION

Mesopancreatic excision is justified, since mesopancreatic fat invasion was evident in the majority of our patients. It is associated with a significantly improved local tumor control as well as longer relapse-free and overall survival.

Meta-analysis of totally extraperitoneal inguinal hernia repair in patients with previous lower abdominal surgery

BACKGROUND

Previous lower abdominal surgery is considered a relative contraindication to laparoscopic totally extraperitoneal (TEP) inguinal hernia repair. This was a meta-analysis of studies comparing the feasibility and safety of TEP repair between patients with (PS), and without (NS) a history of lower abdominal surgery.

METHODS

A systematic literature search was undertaken for studies comparing the outcome of TEP inguinal hernia repair in patients with, and without previous lower abdominal surgery. Data on postoperative outcomes were extracted and compared by meta-analysis. Odds ratios (ORs) and mean differences with 95 per cent confidence intervals were calculated.

RESULTS

Seven comparative cohort studies were identified, involving a total of 1657 procedures (PS 326, NS 1331). There was a statistically significant difference between PS and NS favouring the NS group with regard to both primary outcomes: intraoperative morbidity (OR 2·85, 95 per cent c.i. 1·19 to 6·80; P = 0·02; 7 studies; I²  = 33 per cent), and postoperative morbidity in the multiport subgroup (OR 2·14, 1·28 to 3·58; P = 0·004; 5 studies; I²  = 0 per cent). For the secondary endpoints conversion rate, peritoneal tears, major intraoperative bleeding, postoperative haematoseroma and delay in return to normal activities, there was a statistically significant difference favouring the NS group.

CONCLUSION

This study suggests that patients with previous lower abdominal surgery who need hernia repair get less benefit from TEP repair than those with no history of surgery.

Protection of Mice from Lethal Vaccinia Virus Infection by Vaccinia Virus Protein Subunits with a CpG Adjuvant

Smallpox vaccination carries a high risk of adverse events in recipients with a variety of contra-indications for live vaccines. Although alternative non-replicating vaccines have been described in the form of replication-deficient vaccine viruses, DNA vaccines, and subunit vaccines, these are less efficacious than replicating vaccines in animal models. DNA and subunit vaccines in particular have not been shown to give equivalent protection to the traditional replicating smallpox vaccine. We show here that combinations of the orthopoxvirus A27, A33, B5 and L1 proteins give differing levels of protection when administered in different combinations with different adjuvants. In particular, the combination of B5 and A27 proteins adjuvanted with CpG oligodeoxynucleotides (ODN) gives a level of protection in mice that is equivalent to the Lister traditional vaccine in a lethal vaccinia virus challenge model.

Multifunctional poly(methacrylate) polyplex libraries: A platform for gene delivery inspired by nature

Polymer-based gene delivery systems have enormous potential in biomedicine, but their efficiency is often limited by poor biocompatibility. Poly(methacrylate)s (PMAs) are an interesting class of polymers which allow to explore structure-activity relationships of polymer functionalities for polyplex formation in oligonucleotide delivery. Here, we synthesized and tested a library of PMA polymers, containing functional groups contributing to the different steps of gene delivery, from oligonucleotide complexation to cellular internalization and endosomal escape. By variation of the molar ratios of the individual building blocks, the physicochemical properties of the polymers and polyplexes were fine-tuned to reduce toxicity as well as to increase activity of the polyplexes. To further enhance transfection efficiency, a cell-penetrating peptide (CPP)-like functionality was introduced on the polymeric backbone. With the ability to synthesize large libraries of polymers in parallel we also developed a workflow for a mid-to-high throughput screening, focusing first on safety parameters that are accessible by high-throughput approaches such as blood compatibility and toxicity towards host cells and only at a later stage on more laborious tests for the ability to deliver oligonucleotides. To arrive at a better understanding of the molecular basis of activity, furthermore, the effect of the presence of heparan sulfates on the surface of host cells was assessed and the mechanism of cell entry and intracellular trafficking investigated for those polymers that showed a suitable pharmacological profile. Following endocytic uptake, rapid endosomal release occurred. Interestingly, the presence of heparan sulfates on the cell surface had a negative impact on the activity of those polyplexes that were sensitive to decomplexation by heparin in solution. In summary, the screening approach identified two polymers, which form polyplexes with high stability and transfection capacity exceeding the one of poly(ethylene imine) also in the presence of serum.

Encapsulation status of papillary thyroid microcarcinomas is associated with the risk of lymph node metastases and tumor multifocality

The management of papillary microcarcinoma (PMC) of the thyroid is controversial, especially after partial thyroid resection for benign thyroid disease. In order to detect prognostic factors for PMC, we analyzed 116 patients with PMC for encapsulation status and lymph node metastases. Between 10/1992 and 12/2010, 116 patients with PMC have been operated in our department (87 females, 29 males, median age 49 years). Eighty per cent of PMCs were diagnosed postoperatively. Seventy-six patients (66%) received a more extended resection with either thyroidectomy, near total thyroidectomy, or Dunhill operation either primarily or after completion operation, whereas 40 patients (34%) had only partial resection. Fifty patients (43%) received radioiodine (RIA) ablation. Lymph node metastases were found in 21 patients (18%). Univariate analysis showed four risk factors to be significantly associated with the risk of lymph node metastasis (p<0.05): male gender, younger age, age group<50 years and nonencapsulation of the tumor. Multivariate analysis demonstrated statistical significance for gender and tumor capsulation status. The tumor capsulation status also correlated with tumor multifocality. Our data show that the risk of lymph node metastases is significantly higher in partially or nonencapsulated PMC than in encapsulated specimens. We therefore suggest that the WHO classification should be extended to a compulsory notification of the encapsulation status in PMC.

[Prognostic Value of Preoperative Anaemia and Perioperative Blood Transfusion in Surgical Treatment of Rectal Cancer]

INTRODUCTION

There is evidence for the prognostic value of perioperative blood transfusion in the surgical treatment of patients with rectal cancer in the current literature. Also preoperative anaemia seems to have an impact on the outcome of these patients. The aim of this study was to evaluate the impact of preoperative anaemia and perioperative blood transfusion in patients with rectal cancer treated in our hospital.

PATIENTS AND METHODS

208 patients (81 females, 127 males; median age, 67 years) with rectal cancer were included in this retrospective study. All patients received surgical treatment. In 75 % of the patients an anterior rectum resection was performed while 25 % received an abdominoperineal rectum exstirpation. Patients with neoadjuvant treatment were included and statistical analyses were performed.

RESULTS

107 (51.4 %) patients exhibited preoperative anaemia. Patients with neoadjuvant treatment presented with significantly lower preoperative Hb (haemoglobin) values than patients without neoadjuvant treatment (p = 0.022). Patients with preoperative anaemia received significantly more blood transfusions (p = 0.001), had significantly longer hospital stays (p = 0.023) and significantly lower 5-years overall survival (p = 0.005). Blood transfusion was necessary in 82 patients (39.4 %). These patients presented with a significantly higher rate of perioperative complications (p = 0.01) and a lower 5-years overall survival (p = 0.002). In multivariate analyses neither preoperative anaemia nor perioperative transfusion was a significant prognostic factor.

CONCLUSION

In our study preoperative anaemia and perioperative blood transfusion seems to have an impact on outcome of surgical treatment of patients with rectal cancer. However, in multivariate analyses neither preoperative anaemia nor perioperative transfusion was a significant prognostic factor.

Secondary malignancy in patients with sporadic neuroendocrine neoplasia

The incidence of neuroendocrine neoplasias (NENs), especially of the gastro-entero-pancreatic (GEP), system relatively increased over the past decades, as a result of advanced diagnostic tools, a better clinical awareness, and distinguished pathological diagnostic recognition. Previous reports hypothesized an increased risk for secondary malignancies in patients with NEN especially in GEP-NENs. The present study was designed to investigate the coincidence of NENs and secondary malignancies in a large patient collective. A retrospective analysis was performed on 161 patients (85 female and 76 male) with NEN of various origins. Clinical data of these patients, different classification systems (TNM/WHO), proliferations-based grading, and clinical follow-up were collected and analyzed. Out of 143 patients with a sporadic NEN, 15 (10.49 %) patients were identified with secondary malignant tumors. Median age at the time of the primary operation for NEN was 65 years, whereas the median age of initial diagnosis of associated tumors was 59 years. Mean follow-up time was 61 months. The risk of developing a secondary malignancy was most elevated for patients with an NEN of the lung, the stomach, and the ileum (60, 50 and 20 %, respectively). The spectrum of secondary malignancies included various types of cancer. Kaplan-Meier survival analysis shows a difference suggesting that patients with a secondary malignancy demonstrate a worse survival compared to patients without a secondary tumor; no significance was detected (p = 0.349). Our data suggest that secondary malignancies in patients with NEN's especially in GEP-NENs are found more frequently than in general population. Therefore, patients with NEN need a continuous and detailed follow-up. The reason for the increased incidence of secondary malignancies in patients with NENs remains to be elucidated.

Greenstick fractures of the middle third of the forearm. A prospective multi-centre study

BACKGROUND

Greenstick fractures suffered during growth have a high risk for refracture and posttraumatic deformity, particularly at the forearm diaphysis. The use of a preemptive completion of the fracture by manipulation of the concave cortex is controversial and data supporting this approach are few.

AIM

Aim of this study was to determine the factors which predispose to refracture and deformities, and to define therapeutic strategies.

METHODS

We prospectively gathered clinical and radiographic data over a period of one year on greenstick fractures of the middle third of the forearm in children as part of a multi-centre study. Endpoint was a follow-up visit at one year. Radiographic deformity, state of consolidation at resumption of physical activities and refracture rate were analysed statistically (ANOVA, Student's t-test and Pearson's chi-square test) with regard to patient age, gender, fracture type, therapy and time in plaster.

RESULTS

We collected the data of 103 patients (63 boys, 40 girls), average age 6.6 years (1.3-14.5 years), the vast majority of whom had a combined greenstick fracture of the radius and ulna. 6.7% of the patients sustained a refracture within 49 days (29-76) after plaster removal. They were significantly older (p=0.017) with a significantly higher incidence of manual completion of the fracture with radiographic signs of partial consolidation (p=0.025). Residual deformities were significantly smaller after completion of the fracture compared to reduction without completion (p=0.019) or plaster fixation alone (p<0.005).

CONCLUSIONS

Completion of a greenstick fracture does not prevent refracture. Nevertheless, it diminishes the extent of secondary deformities in cases where the primary angulation exceeds the remodelling capacity. Prevention of refracture should include a routine radiographic follow-up 4-6 weeks after injury with continuation of plaster fixation in cases of partial consolidation.

Interdisciplinary treatment of primary hepatic angiosarcoma: emergency tumor embolization followed by elective surgery

Among primary hepatic malignancies, sarcomas represent a minority of 2 %. Of those, primary hepatic angiosarcoma is the most common one. In the past its incidence has been related to the exposure of certain chemicals like thorotrast, vinyl-chloride or arsenic. - Patients suffering from this aggressive, highly vascular tumor have a poor prognosis in general. Without treatment most of them die after rapid tumor progression with multifocal dissemination. In case of tumor perforation, fatal abdominal hemorrhage has been observed. - We herein report the successful interdisciplinary treatment of an 81 year-old woman with a perforated primary hepatic angiosarcoma of the left hepatic lobe. Initially, tumor bleeding was stopped by emergency interventional coil embolization. After stabilization of the patient, we performed an elective tumor resection. The patient could eventually be discharged in a good clinical condition. - So far, no standard therapy has established for patients with primary hepatic angiosarcoma. Surgery seems to be the treatment of choice. In addition, preoperative interventional embolization of the tumor supplying vessels reduces the risk of pre- and intraoperative bleeding. The value of adjuvant chemotherapy is not yet clarified. - The outcome of most patients with primary hepatic angiosarcoma remains poor and there is a need for clinical studies.

Cardiac tissue Doppler in steroid users

Anabolic steroids cause a variety of side effects, among them a slight concentric left ventricular hypertrophy. The objective of the present study was to clarify if they also induce alterations in left ventricular function. 14 male body builders with substantial intake of anabolic steroids (users) were examined by standard echocardiography and cardiac tissue Doppler imaging. They were compared to 11 steroid-free strength athletes (non-users) and 15 sedentary control subjects. Users showed an increased left ventricular muscle mass index. The ratio of peak transmitral blood flow velocities during early diastolic filling and atrial contraction did not differ between groups (users: 1.4 +/- 0.3; non-users: 1.7 +/- 0.5; controls: 1.4 +/- 0.4). In contrast an analogous tissue Doppler parameter, the ratio of myocardial velocities during early and late ventricular filling in the basal septum, was significantly lower in users (1.2 +/- 0.4) when compared to non-users (1.6 +/- 0.5) or controls (1.6 +/- 0.6). The velocity gradient during myocardial E-wave in the posterior wall showed significantly lower values in users (3.8 +/- 1.3 1/s) as compared to controls (5.8 +/- 2.5 1/s). There were no differences in systolic function. Summarizing strength athletes abusing anabolic steroids show negative alterations in diastolic function.

Characteristics of Inline Speedskating - Incremental Tests and Effect of Drafting

Competitive inline speedskating combines a movement pattern similar to speedskating on ice with pack-oriented competition modes known from cycling. The deep-seated body position leads to high static load and, thus, restricted blood flow within propulsive muscles. This condition may affect lactate kinetics and limit V.O (2peak). The present study compares physiologic reactions to graded cycling and skating exercise among top-level inline speedskaters and quantifies the effect of drafting. Eight male inline speedskaters of the top national level were examined. The study consisted of two graded exhaustive exercise tests (cycling and speedskating) and a pairwise drafting test. All tests were carried out with simultaneous gas exchange (MetaMax 2, Cortex, Germany) and heart rate measurements as well as determination of blood lactate concentrations. Maximal values of oxygen consumption (cycling: 4.91 +/- 0.60; skating: 4.85 +/- 0.50 l . min (-1); p = 0.78), lactate concentration, or heart rate were similar for cycling and skating. At workloads corresponding to blood lactate concentrations of 4 mmol . l (-1) oxygen uptake (cycling: 3.24 +/- 0.65; skating: 3.97 +/- 0.40 l . min (-1); p < 0.05) and heart rate (cycling: 162 +/- 9; skating: 173 +/- 6 min (-1); p < 0.05) were significantly higher during skating. The differences in heart rate ranged between - 2 and 23 min (-1). The drafting effect was 15 +/- 6 % at 30 km . h (-1) (3.34 +/- 0.19 vs. 2.83 +/- 0.29 l . min (-1)) and 14 +/- 5 % at 33 km . h (-1) (3.87 +/- 0.26 vs. 3.32 +/- 0.27 l . min (-1)). During inline speedskating the attainment of VO2peak is not impaired when compared to cycling exercise. However, the derivation of exercise prescriptions from a stepwise cycling test does not seem appropriate. The drafting effect of inline speedskating is within the range known from cycling.

Apoptosis induction in renal cell carcinoma by TRAIL and gamma-radiation is impaired by deficient caspase-9 cleavage

TNF-related apoptosis-inducing ligand (TRAIL APO-2L) is a member of the TNF family and induces apoptosis in cancer cells without affecting most non-neoplastic cells. The present investigation is focused on apoptosis induction by combined exposure to TRAIL and ionising radiation (IR) in human renal cell carcinoma (RCC) cell lines. Here, we demonstrate that all RCC cell lines coexpress TRAIL and the death-inducing receptors, TRAIL-R1 and TRAIL-R2. Exposure to TRAIL alone induced marked apoptosis in three out of eight RCC cell lines. Combined exposure to TRAIL and IR resulted in a sensitisation to TRAIL-induced apoptosis in one RCC cell line only. Enhanced apoptosis induction by TRAIL in combination with IR was paralleled by an increase in PARP cleavage and activation of executioner caspase-3, whereas caspases-6 and -7 were not involved. Moreover, exposure to TRAIL and/or IR resulted in a marked activation of initiator caspase-8, possibly augmented by the observed reduction of inhibitory c-FLIP expression. In contrast to other tumour types, activation of initiator caspase-9 was not detectable in our RCC model system after exposure to TRAIL and/or IR. This lack of caspase-9 activation might be related to an impaired 'crosstalk' with the caspase-8 pathway as suggested by the missing Bid cleavage and to the appearance of an XIAP cleavage product known to inhibit caspase-9 activation. Deficient activation of caspase-9, therefore, might contribute to the clinically known resistance of human RCC against IR and also argues against an effective combination therapy with TRAIL and IR in this tumour type.

TRAIL-beta and TRAIL-gamma: two novel splice variants of the human TNF-related apoptosis-inducing ligand (TRAIL) without apoptotic potential

Tumour necrosis factor (TNF) related apoptosis-inducing ligand (TRAIL/APO2L) is a recently identified member of the TNF family, which induces programmed cell death in a variety of neoplastic cell types, but not in most nonneoplastic cells. In this study, we report on the identification of two novel alternative splice variants of TRAIL in neoplastic and non-neoplastic human cells lacking either exon 3 (TRAIL-beta) or exons 2 and 3 (TRAIL-gamma). In both splice variants, loss of exon 3 resulted in a frame shift generating a stop codon with consecutive extensive truncation in the extracellular domain. Ectopic expression revealed a loss of proapoptotic potential for both alternative splice variants. In contrast to the predominantly cytoplasmatic localisation of GFP-tagged TRAIL-alpha and TRAIL-beta, TRAIL-gamma showed an additional association with the cell surface and nuclear membrane. In conclusion, alternative splicing might be involved in fine tuning of TRAIL-induced apoptosis and underlines the complexity of the TRAIL system.

Expression of different survivin variants in gastric carcinomas: first clues to a role of survivin-2B in tumour progression

Survivin is a novel member of the inhibitor of apoptosis family and determines the susceptibility of tumour cells to pro-apoptotic stimuli. Recently, we identified two novel alternative splice variants of survivin, differing in their anti-apoptotic properties: whereas the anti-apoptotic potential of survivin-DeltaEx3 is preserved, survivin-2B has lost its anti-apoptotic potential and may act as a naturally occurring antagonist of survivin. Because the in vivo expression of these alternative splice variants has not been explored so far, we analysed gastric carcinomas of different histological subtypes, grades and stages. Since no antibodies are currently available to determine the novel splice variants, quantitative reverse transcriptase polymerase chain reaction was performed, using RNA samples obtained from 30 different gastric carcinomas. Polymerase chain reactions products were quantified by densitometric evaluation. We found that all gastric carcinomas, irrespective of their histological types, grades or stages, express survivin-DeltaEx3, survivin-2B and survivin, the latter being the dominant transcript. Comparing the disease stages I+II with III+IV, expression of survivin and survivin-DeltaEx3 remained unchanged. In contrast, a significant (P=0.033) stage-dependent decrease in the expression of survivin-2B became evident. Our study demonstrates for the first time the expression of alternative splice variants in gastric carcinomas and provides a first clue to a role of survivin-2B in tumour progression.

Sensitivity to TRAIL/APO-2L-mediated apoptosis in human renal cell carcinomas and its enhancement by topotecan

TRAIL (APO-2L) is a newly identified member of the TNF family and induces apoptosis in cancer cells without affecting most non-neoplastic cells, both in vitro and in vivo. Our study focused on the expression and function of TRAIL and its receptors in renal cell carcinoma (RCC) cell lines of all major histological types. Here, we demonstrate that all RCC cell lines express TRAIL as well as the death-inducing receptors TRAIL-R1 (DR4) and TRAIL-R2 (Killer/DR5). Exposure to TRAIL induced apoptosis in 10 of 16 RCC cell lines. Remarkably, five of six TRAIL-resistant RCC cell lines exhibited high levels of TRAIL expression. Topotecan, a novel topoisomerase I inhibitor, induced upregulation of TRAIL-R2 as well as downregulation of TRAIL. Neutralization of TRAIL with recombinant soluble TRAIL-R1-Fc and TRAIL-R2-Fc failed to inhibit topotecan-induced apoptosis indicating that topotecan-induced cell death can occur in a TRAIL-independent fashion. However, exposure to topotecan resulted in an enhancement of TRAIL-induced apoptosis in all primarily TRAIL-resistant RCC cell lines. This synergistic effect of cotreatment with Topotecan and TRAIL may provide the basis for a new therapeutic approach to induce apoptosis in otherwise unresponsive RCC.

Increased utilization of polyreactive B cells during periods of generalized immune activation

This work examines the hypothesis that B cells secreting polyreactive antibodies (antibodies capable of binding to more than one self or foreign antigen) are preferentially utilized during periods of generalized immune stimulation. Four conditions characterized by such stimulation were examined: chronic virus infection, mitogen treatment, autoimmune disease and neonatal repertoire development. In normal adult mice, polyreactive IgM secreting lymphocytes constituted 8-9% of the actively expressed repertoire. Under conditions of generalized immune activation, this frequency increased to 13-19% (p. < .01). Polyreactive IgG secreting B cells, which were present at frequencies of < 0.5% in normal adult mice, were found at freqeuncies of 6-10% in mice with autoimmune disease, chronic virus infection or following mitogen treatment (p. < .001). We postulate that polyreactive lymphocytes are preferentially activated when the immune system is confronted with stimuli inadequately controlled by antigen-specific responses.

Effect of cyclophosphamide, total body irradiation, and zidovudine on retrovirus proliferation and disease progression in murine AIDS

Murine acquired immunodeficiency syndrome (MAIDS) develops when C57B1/6 mice are inoculated with LP-BM5 murine leukemia viruses. Disease progression in these animals is characterized by lymphadenopathy, polyclonal B-cell activation, severe immunodeficiency, and death. Mice with MAIDS have been used to examine the efficacy of antiretroviral therapies for possible use in AIDS patients. In the present work, MAIDS mice were employed to test the hypothesis that established retroviral infection might be cured by the combined use of a cytotoxic agent (cyclophosphamide) and total body irradiation--a regimen reported to have successfully cured HIV-1 infection in one AIDS patient. Results indicate that the ablation of retrovirus-infected lymphoid cells reduced but did not eliminate LP-BM5 infection. Moreover, this regimen was no more effective at controlling virus proliferation or preventing the polyclonal IgG activation characteristic of murine AIDS than was AZT alone.

Detection of antibodies to caprine arthritis-encephalitis virus by protein G enzyme-linked immunosorbent assay and immunoblotting

Sera from goats suffering from caprine arthritis-encephalitis contained antibodies to virus proteins of 15, 17, 28, 40, and 130 kilodaltons in immunoblots of maedi-visna virus. We propose to use immunoblotting as a validation test for enzyme-linked immunosorbent assay and demonstrate that the specificity of indirect enzyme-linked immunosorbent assay can be improved by replacing second antibody by a protein G-avidin-biotin conjugate.

Cyanide poisoning from metal cleaning solutions

We report two cases of cyanide poisoning from accidental ingestion of an imported metal cleaning solution used by some Southeast Asians for shining coins. Both patients received specific therapy and recovered completely after a dramatic sequence of sudden collapse and severe cardiovascular compromise.

Stochastic thresholds

Thresholds have traditionally been represented by a single number; the optimal management of the patient depends on whether his probability of disease is above or below this number. The concept of a threshold as a single number, however, inadequately represents the treatment approach of a group of physicians who do not have all the same threshold or a single physician who is uncertain about the exact value of the threshold. An alternative to a single valued threshold is to consider the threshold as having a probability distribution: for every probability that the patient has the disease there is a probability that the threshold is exceeded. This "stochastic" threshold model contains information about the uncertainty of the threshold estimation. Stochastic thresholds can be useful for testing the sensitivity of a management decision to the patient's probability of disease. They can also be used for comparing the standards of practice of individual physicians or comparing the practice of an individual physician with that of a group.