Combined abdominoplasty and stoma repositioning: A successful approach for addressing stomal retraction and problematic stoma care: A case study.

INTRODUCTION: This case report discusses the management of challenging stoma care in an overweight patient, focusing on the successful application of abdominoplasty combined with stoma repositioning. The increasing abdominal mass in overweight patients often leads to stoma retraction and mechanical stress, necessitating innovative and less invasive interventions. CASE PRESENTATION: The subject is a 40-year-old female with a body mass index of 28.41 kg/m2, who was experiencing complications in stoma care due to recent weight gain. Through a collaborative effort between a plastic and a general surgeon, the patient underwent abdominoplasty combined with stoma repositioning, leading to significant improvements in stoma care and cosmetic results. DISCUSSION: Despite the limited amount of literature on abdominoplasty combined with stoma revision, this case report contributes to the evidence supporting it as an effective alternative for persistent stoma dysfunction in overweight patients. This innovative surgical approach represents a viable solution to address stomal retraction and leakage. CONCLUSION: The case report underscores the potential benefits of abdominoplasty combined with stoma repositioning in overweight patients with persistent stoma care problems. Although the risk of wound contamination must be taken into account, this combined procedure can enhance patient outcomes. The study provides valuable insights for healthcare professionals managing stoma care in overweight patients.

Locoregional recurrences after transanal total mesorectal excision of rectal cancer during implementation.

BACKGROUND: Transanal total mesorectal excision (TaTME) has been proposed as an approach in patients with mid and low rectal cancer. The TaTME procedure has been introduced in the Netherlands in a structured training pathway, including proctoring. This study evaluated the local recurrence rate during the implementation phase of TaTME. METHODS: Oncological outcomes of the first ten TaTME procedures in each of 12 participating centres were collected as part of an external audit of procedure implementation. Data collected from a cohort of patients treated over a prolonged period in four centres were also collected to analyse learning curve effects. The primary outcome was the presence of locoregional recurrence. RESULTS: The implementation cohort of 120 patients had a median follow up of 21·9 months. Short-term outcomes included a positive circumferential resection margin rate of 5·0 per cent and anastomotic leakage rate of 17 per cent. The overall local recurrence rate in the implementation cohort was 10·0 per cent (12 of 120), with a mean(s.d.) interval to recurrence of 15·2(7·0) months. Multifocal local recurrence was present in eight of 12 patients. In the prolonged cohort (266 patients), the overall recurrence rate was 5·6 per cent (4·0 per cent after excluding the first 10 procedures at each centre). CONCLUSION: TaTME was associated with a multifocal local recurrence rate that may be related to suboptimal execution rather than the technique itself. Prolonged proctoring, optimization of the technique to avoid spillage, and quality control is recommended.

ANTECEDENTES: La escisión total del mesorrecto por vía transanal (Transanal Total Mesorectal Excision, TaTME) se ha propuesto como abordaje quirúrgico en pacientes con cáncer de recto medio e inferior. La técnica TaTME se ha introducido en los Países Bajos mediante un proceso de formación estructurado que incluye la supervisión. Este estudio evaluó el porcentaje de recidiva local durante la fase de implementación de TaTME. MÉTODOS: Se recogieron los resultados oncológicos de los primeros 10 procedimientos realizados mediante TaTME en cada uno de los 12 centros participantes como parte de una auditoría externa de implementación del procedimiento. Se reunió una cohorte más amplia de pacientes procedentes de 4 centros para analizar los efectos de la curva de aprendizaje. El criterio de valoración principal fue la presencia de recidiva locorregional. RESULTADOS: La cohorte de implementación de 120 pacientes tuvo una mediana de seguimiento de 21,9 meses. Los resultados a corto plazo incluyeron una tasa del margen de resección circunferencial positivo del 5% y una tasa de fuga anastomótica del 17,4%. La tasa global de recidiva local en la cohorte de implementación fue del 10% (12/120) con un intervalo medio de recidiva de 15,2 (DE 7) meses. El patrón de recidiva local fue multifocal en 8 de 12 casos (67%). En la cohorte ampliada (n = 266), la tasa global de recidiva fue del 5,6% (4,0%, excluyendo a los primeros 10 pacientes). CONCLUSIÓN: TaTME se asoció con un porcentaje de recidiva local multifocal que puede relacionarse con una ejecución subóptima, más que con la técnica en sí. Se recomienda una supervisión prolongada, la optimización de la técnica para evitar la diseminación tumoral, así como un control de calidad.

Accumulation of human EGF in nectar of transformed plants of Nicotiana langsdorffii x N. sanderae and transfer to honey by bees.

Honey has been used successfully in wound healing for thousands of years. The peptide hormone human epidermal growth factor (hEGF) is also known to have a beneficial effect in various wound healing processes via mechanisms that differ from those for honey. In this study, we show that hEGF can be incorporated into honey via nectar. Plants of Nicotiana langsdorffii x N. sanderae were transformed with the gene for hEGF, equipped with a nectary-targeted promoter and a signal sequence for secretion to nectar. These plants accumulated hEGF in the nectar. The maximum hEGF concentration recorded with ELISA in these plants is 2.5 ng·ml⁻¹. There is a significant linear relationship (P<0.001) between hEGF concentration and induction of hEGF-receptor phosphorylation. Since the flower morphology of these plants did not allow production of honey from their nectar, we used feeding solutions, spiked with synthetic hEGF, to study transfer of this peptide into honey through bee activity. Transfer of hEGF from a feeding solution to honey by bees occurred with retention of the hEGF concentration and the capacity to induce hEGF-receptor phosphorylation. These observations indicate that plants can function as a production platform for honey containing biologically active peptides, which may enhance wound healing and other biological processes.

Human kappa light chain targeted Pseudomonas exotoxin A--identifying human antibodies and Fab fragments with favorable characteristics for antibody-drug conjugate development.

Antibody-drug conjugates (ADC) represent promising agents for targeted cancer therapy. To allow rational selection of human antibodies with favorable characteristics for ADC development a screening tool was designed obviating the need of preparing individual covalently linked conjugates. Therefore, α-kappa-ETA' was designed as a fusion protein consisting of a human kappa light chain binding antibody fragment and a truncated version of Pseudomonas exotoxin A. α-kappa-ETA' specifically bound to human kappa light chains of human or human-mouse chimeric antibodies and Fab fragments. Antibody-redirected α-kappa-ETA' specifically inhibited proliferation of antigen-expressing cell lines at low toxin and antibody concentrations. Selected antibodies that efficiently delivered α-kappa-ETA' in the novel assay system were used to generate scFv-based covalently linked immunotoxins. These molecules efficiently triggered apoptosis of target cells, indicating that antibodies identified in our assay system can be converted to functional immunoconjugates. Finally, a panel of human epidermal growth factor receptor (EGFR) antibodies was screened--demonstrating favorable characteristics with antibody 2F8. These data suggest that antibodies with potential for Pseudomonas exotoxin A-based ADC development can be identified using the novel α-kappa-ETA' conjugate.

N(epsilon)-(carboxymethyl)lysine depositions in intramyocardial blood vessels in human and rat acute myocardial infarction: a predictor or reflection of infarction?

OBJECTIVE: Advanced glycation end products (AGEs), such as N(epsilon)-(carboxymethyl)lysine (CML), are implicated in vascular disease. We previously reported increased CML accumulation in small intramyocardial blood vessels in diabetes patients. Diabetes patients have an increased risk for acute myocardial infarction (AMI). Here, we examined a putative relationship between CML and AMI. METHODS AND RESULTS: Heart tissue was stained for CML, myeloperoxidase, and E-selectin in AMI patients (n=26), myocarditis patients (n=17), and control patients (n=15). In AMI patients, CML depositions were 3-fold increased compared with controls in the small intramyocardial blood vessels and predominantly colocalized with activated endothelium (E-selectin-positive) both in infarction and noninfarction areas. A trend of increased CML positivity of the intima of epicardial coronary arteries did not reach significance in AMI patients. In the rat heart AMI model, CML depositions were undetectable after 24 hours of reperfusion, but became clearly visible after 5 days of reperfusion. In line with an inflammatory contribution, human myocarditis was also accompanied by accumulation of CML on the endothelium of intramyocardial blood vessels. CONCLUSIONS: CML, present predominantly on activated endothelium in small intramyocardial blood vessels in patients with AMI, might reflect an increased risk for AMI rather than being a result of AMI.

Hybrid zones between invasive Rorippa austriaca and native R. sylvestris (Brassicaceae) in Germany: ploidy levels and patterns of fitness in the field.

Hybrid zones may serve as natural laboratories for evolutionary studies. One common viewpoint is that hybrids may always be less fit than their parents due to genetic discontinuities. An alternative idea is that genotype-environment interactions influence the outcome of natural hybridization. Our comparative study of two different natural hybrid zones between the invasive diploid Rorippa austriaca and the native polyploid R. sylvestris in Germany identified the ploidy level as a major determinant of hybrid fitness. Different ploidy levels and patterns of fitness were detected in different hybrid zones. In one hybrid zone (Mülheim, Ruhr valley) hybrids were pentaploid and showed a relatively high seed set, whereas in the second hybrid zone (Randersacker, Main valley) hybrids were triploid and displayed extremely low fitness values. Analyses of fitness values in different natural hybrid zones between the same two species may lead to very different conclusions about the evolutionary significance of natural hybridization.

Hybridization and Rorippa austriaca (Brassicaceae) invasion in Germany.

Introgressive hybridization between the invasive Rorippa austriaca and the native R. sylvestris in Germany has been studied using chloroplast DNA (trnL intron) and amplified fragment length polymorphism. Three hybrid zones between the invasive and native species were located in the Ruhr Valley (Mülheim) and at the River Main near Würzburg (Randersacker, Winterhausen). In each hybrid zone hybridization was indicated by additivity of region-specific amplified fragment length polymorphism markers proving independent hybridization events. The hybrids were either morphologically intermediate (R. x armoracioides) or were close to R. sylvestris. The trnL intron of R. austriaca is characterized by a species-specific deletion. This diagnostic chloroplast marker of R. austriaca was detected in three individuals of R. sylvestris providing evidence for introgression of the invasive chloroplast into the native species. Bidirectional introgression of R. austriaca markers into R. sylvestris and of R. sylvestris markers into R. austriaca was detected in the amplified fragment length polymorphism analysis. Some of the invasive R. austriaca populations showed high within-population variation. A possible association among introgression, within-population variation and invasion success is discussed. The morphologically intermediate hybrid R. x armoracioides is currently spreading in northern Germany. It forms large populations without its parent species R. austriaca and R. sylvestris. It is concluded that hybridization between invasive R. austriaca and native R. sylvestris may lead to the evolution of a new invasive species R. x armoracioides.

Accelerated autoantibody clearance by intravenous immunoglobulin therapy: studies in experimental models to determine the magnitude and time course of the effect.

Recently, it has been postulated that the beneficial effect of intravenous immunoglobulins (IVIGs) in antibody-mediated autoimmune disorders is based on accelerated catabolism of autoantibodies. In the current study, in vivo experiments were performed with mice in which autoantibody production was mimicked by continuous infusion of monoclonal antibodies. In this model, a single dose of IVIG reduced the plasma concentrations of the infused immunoglobulin (Ig)G1 monoclonal antibody (mAb) by approximately 40% after 3 days, whereas the concentration of an IgA mAb was not affected. To extrapolate these findings to humans, a computational model for IgG clearance was established that accurately predicted the time course and magnitude of the decrease in IgG plasma levels observed in mice. Adapted for humans, this model predicted a gradually occurring decrease in autoantibody levels after IVIG administration (2 g/kg), with a maximum reduction of approximately 25% after 3 to 4 weeks and a continued decrease of several months. In conclusion, a single high dose of IVIG induces a relatively small but long-lasting reduction of autoantibody levels by accelerated IgG clearance. This mechanism has clinical relevance in the sense that it can fully explain, as the sole mechanism, the gradual decrease in autoantibody levels observed in several patient studies. However, in some clinical studies, larger or more rapid effects have been observed that cannot be explained by accelerated clearance. Hence, IVIG can also reduce autoantibody levels through mechanisms such as down-regulation of antibody production or neutralization by anti-idiotypic antibodies.

Introgressive hybridization in Rorippa (Brassicaceae): gene flow and its consequences in natural and anthropogenic habitats.

Introgressive hybridization between three Rorippa species (R. amphibia, R. palustris and R. sylvestris) in northern Germany has been studied using isozymes and noncoding chloroplast DNA (trnL/F spacer). Our results provide substantial evidence for different patterns of gene flow in natural and in anthropogenic environments. Hybridization and bi-directional introgression (chloroplast DNA and allozymes) between R. amphibia and R. sylvestris were detected at the river Elbe, which is one of the last rivers in Central Europe showing a natural dynamic of erosion and sedimentation. The natural dynamic of the Elbe leads to periodic habitat disturbance and the temporal breakdown of ecological isolation barriers between R. amphibia and R. sylvestris. However, the high dynamic does not provide the opportunity for persistence of the morphologically intermediate hybrid R. x anceps (R. amphibia x R. sylvestris). We did not find hybrid zones between R. amphibia and R. sylvestris in the more anthropogenic landscape of northwest Germany. However, contact zones between R. amphibia and R. palustris were detected in drainage ditches in northwest Germany. We found substantial evidence for unidirectional introgression of R. palustris markers (chloroplast DNA and allozymes) into R. amphibia in the man-made habitats. The R. amphibia introgressants in the drainage ditches often showed strongly serrate upper cauline leaves instead of the entire upper cauline leaves typical for R. amphibia. We argue that landscape melioration in northwest Germany, particularly the creation of drainage ditches, favoured both hybrid-zone formation and ecotypic differentiation within R. amphibia.

Therapeutic efficacy of intravenous immunoglobulin preparations depends on the immunoglobulin G dimers: studies in experimental immune thrombocytopenia.

The clinical benefit of intravenous immunoglobulin (IVIG) preparations in the treatment of immune thrombocytopenic purpura (ITP) is supposed to be mediated by blockade of Fc gamma receptor--bearing phagocytes. In 2 experimental models for ITP, it is shown that the therapeutic efficacy of IVIG preparations is related to the IgG dimer content present in these preparations. A rat monoclonal antibody (mAb; MWReg30) directed to the murine platelet-specific integrin alpha(IIb)beta(3) (gpIIb/IIIa) was administered intraperitoneally either as bolus injection or continuous infusion. With bolus injection, the circulating platelet count dropped to almost zero within 3 hours. Pretreatment with cobra venom factor did not affect platelet depletion, whereas pretreatment with anti-Fc gamma RII/III mAb 2.4G2 or IVIG greatly reduced platelet clearance. With continuous infusion, platelet numbers reached a steady state after 4 days, at approximately 25% of control. This reduction in platelets was, however, not observed in mice deficient for the FcR gamma-chain, lacking Fc gamma RI, Fc gamma RIII, and Fc gamma RIII(-/-) mice. Infusion of a single dose of IVIG with a high IgG dimer content on the 4th day--ie, mimicking therapeutic administration--resulted in a platelet increase for several days. IVIG predominantly consisting of monomeric IgG had no effect on platelet numbers. In conclusion, continuous infusion of MWReg30 induces thrombocytopenia in mice by enhancing Fc gamma receptor--mediated clearance of platelets. In this model, it is shown that IgG dimers present in IVIG preparations are responsible for the increase in platelet counts. (Blood. 2001;98:1095-1099)

The potentiation of human C1-inhibitor by dextran sulphate is transient in vivo: studies in a rat model.

C1-inhibitor (C1-Inh) is an important regulator of inflammatory reactions because it is a potent inhibitor of the contact and complement system. C1-Inh application in inflammatory disease is, however, restricted because of the high doses required. The glycosaminoglycan-like molecule dextran sulphate (DXS) enhances C1-Inh function in vitro. Hence, we investigated whether co-administration with dextran sulphate reduces the amount of C1-Inh required, through enhancement in vivo. C1-Inh potentiation was measured in a newly developed C1s-inactivation assay that is based on activation of C4 by purified C1s. Activated C4 in rat plasma was quantified with a newly developed ELISA. Human C1-Inh (2.5 microM) inhibited C1s in rat plasma 55-fold faster in the presence of dextran sulphate (15 kDa, 5 microM). To study the stability of the complex in vivo, rats were given a mixture of C1-Inh (10 mg/kg) and dextran sulphate (3 mg/kg). C1-Inh activity during 5 h was analyzed ex vivo with the C1s inactivation assay. The noncovalent C1-Inh-dextran sulphate complex resulted in a transient enhancement of the inhibitory capacity of C1-Inh, lasting for 60-90 min. Dextran sulphate did not affect plasma clearance of C1-Inh. We conclude that the enhanced inhibitory capacity of C1-Inh complexed to dextran sulphate is transient in vivo. Hence, co-administration of these compounds seems a feasible approach to achieve short-term inhibition of complement in vivo.

Prognostic significance of K-ras and TP53 mutations in the role of adjuvant chemotherapy on survival in patients with Dukes C colon cancer.

PURPOSE: Mutations in K-ras and TP53 genes are common in colorectal cancer. They affect biologic behavior and might influence chemotherapy susceptibility in these tumors. We investigated whether the survival of patients with Dukes C colon cancer treated with adjuvant chemotherapy is influenced by K-ras and TP53 mutations. METHODS: Mutation screening of the hot spots of the K-ras gene and of the evolutionarily conserved regions of the TP53 gene was performed by denaturing gradient gel electrophoresis technique in formalin-fixed paraffin-embedded specimens of 55 consecutive patients with Dukes C colon cancer treated with adjuvant 5-fluorouracil-based chemotherapy. The median follow-up was 47 (range, 32-66) months. RESULTS: Alterations in the mutation hot spots of K-ras were found at codon 12 (n = 11) and 13 (n = 4) in 15 of the 55 carcinomas (27 percent). No mutation was found at codon 61. Mutations of a probably causative nature in the evolutionarily conserved regions (exons 5-8) of the TP53 gene were found in 24 tumors (44 percent). K-ras and TP53 mutations were found equally in the group with recurrent disease (7/26 (26 percent) and 12/27 (44 percent), respectively) and in the group without recurrences (8/28 (24 percent) and 12/28 (43 percent), respectively). Cancer-specific survival did not differ significantly between patients with K-ras or TP53 or both mutated and nonmutated tumors, respectively (log-rank test: K-ras, P = 0.72 and TP53, P = 0.77; K-ras and TP53, P = 0.8). Also, potentially aggressive K-ras codon 12 and 13 mutations had the same survival as tumors without these mutations (log-rank test; P = 0.73). CONCLUSIONS: Patients with K-ras or TP53 or both mutated Dukes C colon tumors have the same survival as nonmutated tumors when treated with adjuvant chemotherapy. These data suggest that mutations in K-ras or TP53 alone are not prognostic indicators in patients with Dukes C colon cancer receiving adjuvant 5-Fluorouracil-based therapy.

Intravenous immunoglobulin preparations induce mild activation of neutrophils in vivo via triggering of macrophages--studies in a rat model.

Despite widespread use in various immune disorders, the in vivo mechanisms of action of intravenous immunoglobulin (IVIG) preparations are not well known. We previously reported that human neutrophils degranulate after incubation with IVIG in vitro as a result of interaction with FcgammaRII. The purpose of this study was to determine whether IVIG might stimulate neutrophils in vivo. Anaesthetized rats received a bolus intravenous injection of IVIG preparations, containing either high (aged IVIG) or low (fresh IVIG) amounts or IgG dimers at a dose of 250 mg/kg. Administration of aged IVIG induced neutrophil activation in vivo, whereas no effect was observed after infusion of fresh IVIG. Histological examination of lung tissue demonstrated mild influx of neutrophils into the pulmonary tissue after aged IVIG administration, though gross damage did not occur. Macrophage-depleted rats no longer showed activation of neutrophils after infusion of aged IVIG, suggesting that neutrophils become activated via an indirect macrophage dependent way. We conclude that IVIG induces a mild activation of neutrophils in vivo via triggering of macrophages depending on the amount of IgG dimers. For this reason, IVIG preparations with a high content of dimers may not always be as harmless as generally believed and may be responsible for some of the side-effects observed during IVIG infusions.

Value and cost of follow-up after adjuvant treatment of patients with Dukes' C colonic cancer.

BACKGROUND: The clinical value and costs of different diagnostic tools used to identify potentially curable recurrent disease in patients treated adjuvantly for curatively resected Dukes' C colonic cancer were examined. METHODS: The study group comprised 496 patients treated with chemotherapy over a 1-year interval. Follow-up consisted of interim history, physical examination, liver ultrasonography or computed tomography (CT), measurement of carcinoembryonic antigen (CEA) levels, chest radiography and colonoscopy. RESULTS: Two hundred and thirteen patients had recurrent disease (median follow-up 43 months). Forty-two patients with recurrence (20 per cent) were treated with curative intent (median survival 38 months; 5-year survival rate 40 per cent). Recurrence was identified by liver ultrasonography or CT (n = 14), evaluation of symptoms (n = 12), colonoscopy (n = 8), CEA measurement (n = 3), chest radiography (n = 2), physical examination (n = 1) and other modalities in two patients. The mean cost of diagnostic procedures per curative resected recurrence for patients amenable to salvage surgery was US$9011. Of all treatable recurrences, 12 of 42 were identified by evaluation of symptoms only. Ultrasonography and colonoscopy identified 22 recurrences at a cost of US$11 790 per patient, while routine follow-up by CEA measurement, chest radiography and physical examination identified a further six at a cost of US$19 850 per patient. CONCLUSION: Potentially curable recurrences were detected primarily by liver imaging and colonoscopy. The yield of CEA measurement, chest radiography and physical examination was relatively low; such methods were expensive and should not be recommended in the routine follow-up of these patients.

New comprehensive denaturing-gradient-gel- electrophoresis assay for KRAS mutation detection applied to paraffin-embedded tumours.

A comprehensive mutation detection assay is presented for the entire coding region and all splice site junctions of the KRAS oncogene. The assay is based on denaturing gradient gel electrophoresis and applicable to archival paraffin-embedded tumour material. All KRAS amplicons are analysed within two lanes of a DGGE gel under a single set of experimental conditions. Six known codon 12 mutations in genomic DNA from different paraffin-embedded tumours could readily be detected. When testing 35 paraffin-embedded Dukes' C colorectal carcinomas for unknown mutations, 12 tumours were found with mutations in codons 12 or 13. None of the tumours appeared to have a codon 61 mutation. In nine tumours, however, 11 additional sequence variations were found outside the hot-spot codons. None of these occurred in germline DNA from 57 individuals. Of these variations, three are considered as significant mutations, as they result in a non-conservative substitution of amino acid residues essential for the functioning of the KRAS protein. Thus, in total, 15 of the 35 Dukes' C tumours (43%) had a KRAS mutation of functional significance. Moreover, a novel exon 4B polymorphism was found to occur in 10 of the 35 tumours. The results of this study suggest that in restricting analysis of KRAS to hot-spot mutation sites only, significant information may be missed.

Impact of KRAS and TP53 mutations on survival in patients with left- and right-sided Dukes' C colon cancer.

OBJECTIVE: It has been suggested that KRAS and TP53 mutated tumors might influence the phenotypic behavior of left- and right-sided colon tumors. We investigated the incidence of these mutations in left- and right-sided colon tumors and their possible influence on survival in a homogeneous group of patients with Dukes' C colon cancers. METHODS: The primary tumors of 55 patients with a sporadic Dukes' C colon cancer, all treated with adjuvant chemotherapy were analyzed for the presence of KRAS and TP53 mutations. Mutation detection of the KRAS and TP53 genes was performed on paraffin-embedded tumor material, using denaturating gradient gel electrophoresis. The 5-yr survival rates of KRAS and TP53 mutated tumors were analyzed regarding right-sided tumors (defined as tumors up to the splenic flexure) and left-sided tumors (defined as tumors from the splenic flexure to the rectosigmoid peritoneal reflection). RESULTS: KRAS mutations occurred more frequently in the right colon compared to the left colon (R = 38% (10/26); L = 10% (3/29); chi2 test: p = 0.014). KRAS mutations did not influence survival in patients with right-sided colon tumors. Patients with KRAS mutation-negative tumors in the right colon, however, had a significantly worse survival than patients with left-sided KRAS mutation-negative tumors (5-yr survival; R: 34% vs L: 65%, log-rank test: p = 0.007). TP53 mutations of a possible causative nature were found in 24 tumors (44%). Neither the incidence (R = 42% (11/26); L = 45% (13/29)) nor the survival of TP53 mutated tumors differed significantly between left- and right-sided tumors. Furthermore, survival of patients with TP53 mutation-negative tumors did not differ significantly between left- and right-sided tumors. CONCLUSIONS: There seems to be no difference in survival rate between patients with KRAS mutated and KRAS negative Dukes' C colon tumors; however, KRAS mutations are more frequently found in the right colon compared to the left colon. TP53 mutations do not have predominance for either side of the colon, and there are no differences in survival in patients with left-sided versus right-sided tumors. Patients with KRAS-nonmutated tumors in the right colon did have a worse survival compared to those with such tumors in the left colon. This suggests that other genetic factors may play a role in tumor genesis in this subgroup of patients.

In vivo effects of Hb solutions on blood viscosity and rheologic behavior of RBCs: comparison with clinically used volume expanders.

BACKGROUND: Hb-based oxygen carriers (HbOCs) have vasoactive effects that are still poorly understood. Factors known to have vasoactive effects, such as plasma, whole-blood viscosity, and the rheologic behavior of RBCs, are modulated by HbOCs in vitro, but few in vivo studies have been performed. STUDY DESIGN AND METHODS: Rabbits were phlebotomized (30%) and resuscitated with unmodified stroma-free Hb (SFHb), dextran-tetracarboxylate-Hb (Dex-BTC-Hb), O-raffinose-polymerized Hb (OrpHb), HSA, or hydroxyethyl starch 200 (HES). Plasma viscosity was assessed with a capillary viscometer and whole-blood viscosity with a rotational viscosimeter. RBC aggregation kinetics were determined by analysis of back-scattered light in a rotating device. RESULTS: As compared to that in the control RBC suspension, resuscitation with SFHb, OrpHb, or HSA decreased plasma and whole-blood viscosity as well as RBC aggregation; resuscitation with Dex-BTC-Hb increased whole-blood viscosity at low shear rates as well as RBC aggregation, whereas that with HES decreased whole-blood viscosity but increased RBC aggregation. CONCLUSION: HbOCs have different rheologic effects in vitro and in vivo. There are marked differences among the Hb solutions in their in vivo effects on viscosity and RBC rheologic behavior (especially at low shear rates encountered in the venous circulation and the microcirculation), which may be related to the chemical modifications applied to hemoprotein. These results could contribute to an understanding of the vasoactive effects of HbOCs.

The addition of low-dose leucovorin to the combination of 5-fluorouracil- levamisole does not improve survival in the adjuvant treatment of Dukes' C colon cancer. IKN Colon Trial Group.

PURPOSE: To assess the effect of the addition of leucovorin to the combination of 5-fluorouracil (5-FU)-levamisole on recurrence risk and overall survival in patients after a resection with curative intent of a Dukes' C colon cancer. PATIENTS AND METHODS: Five hundred patients with Dukes' C colon cancer were randomly assigned to adjuvant treatment for one year with 5-fluorouracil (450 mg/m2 i.v. weekly) and levamisole (150 mg p.o. every two weeks), the C-group or with leucovorin (20 mg/m2 i.v.), 5-fluorouracil and levamisole, the L-group. The median follow-up for patients still alive is 36 months. Four patients were ineligible because of advanced disease at the time of randomisation. RESULTS: Sixty percent of the patients have completed all courses of chemotherapy. Of the remaining 40% of the patients who did not complete one-year treatment with chemotherapy, 46% discontinued because of toxic and/or emotional reasons. They were equally divided over both treatment arms. The addition of leucovorin increased toxicity (especially mucositis and conjunctivitis) without a significant increase in treatment withdrawal. Five-year disease-free interval (C-group: 49%, L-group: 46%; log-rank test, P = 0.86) and overall survival (C-group: 55%, L-group: 59%, log-rank test: P = 0.96) were very similar in both treatment arms. CONCLUSIONS: The addition of low dose leucovorin to the combination of 5-fluorouracil and levamisole in a 12-month adjuvant therapy for curatively resected Dukes' C colon cancer patients does not improve disease-free interval nor overall survival. The addition of leucovorin to the combination of 5-FU levamisole increases toxicity. Therefore leucovorin 5-FU levamisole is not recommended in a 12 months adjuvant regime of Dukes' C colon cancer.

Vasoactive side effects of intravenous immunoglobulin preparations in a rat model and their treatment with recombinant platelet-activating factor acetylhydrolase.

Previously, we observed in a rat model that intravenous administration of intramuscular immunoglobulin preparations induced a long-lasting hypotension, which appeared to be associated with the presence of IgG polymers and dimers in the preparations, but unrelated to complement activation. We found evidence that this hypotensive response is mediated by platelet-activating factor (PAF) produced by macrophages. In this study, we compared the vasoactive effects of 16 intravenous immunoglobulin (IVIG) products from 10 different manufacturers, in anesthetized rats. Eight of the IVIG preparations showed no hypotensive effects (less than 15% decrease), whereas the other 8 had relatively strong effects (15%-50% decrease). The hypotensive effects correlated with the IgG dimer content of the preparations. Pretreatment of the rats with recombinant PAF acetylhydrolase completely prevented the hypotensive reaction on IVIG infusion, and administration after the onset of hypotension resulted in normalization of the blood pressure. We also observed PAF production on in vitro incubation of human neutrophils with IVIG, which could be blocked by anti-Fcgamma receptor antibodies. This indicates that induction of PAF generation may also occur in a human system. Our findings support the hypothesis that the clinical side effects of IVIG in patients may be caused by macrophage and neutrophil activation through interaction of IgG dimers with Fcgamma receptors. Because phagocyte activation may also lead to the release of other inflammatory mediators, recombinant PAF acetylhydrolase (rPAF-AH) provides a useful tool to determine whether PAF plays a role in the clinical side effects of IVIG. If so, rPAF-AH can be used for the treatment of those adverse reactions. (Blood. 2000;95:1856-1861)

Comprehensive TP53-denaturing gradient gel electrophoresis mutation detection assay also applicable to archival paraffin-embedded tissue.

A comprehensive mutation detection assay is described for the entire coding region and all splice site junctions of TP53. The assay is based on denaturing gradient gel electrophoresis, which follows either multiplex polymerase chain reaction (PCR) applied to DNA extracted from fresh or frozen tissue samples or nested PCR applied to DNA extracted from paraffin-embedded tissue samples. In both instances, the analysis can be performed under a single set of conditions. When testing the assay on DNA from cultured lung cancer cell lines and from paraffin-embedded Dukes C colorectal carcinomas, significant TP53 mutations were observed at high frequencies in 15 of 16 lung cancer cell lines (94%) and in 21 of 30 paraffin-embedded tissue samples of Dukes C colorectal carcinomas (70%). A substantial proportion of these significant mutations occurred outside the evolutionary conserved region of TP53 in 4 of 16 lung cancer cell lines (25%) and in 11 of 30 paraffin-embedded colorectal carcinomas (37%). This underscores the importance of a comprehensive TP53 mutation analysis in those instances that TP53 mutation is taken into account for diagnostic and prognostic purposes.