Mechanisms affecting the gut of preterm infants in enteral feeding trials: a nested cohort within a randomised controlled trial of lactoferrin

OBJECTIVE

To determine the impact of supplemental bovine lactoferrin on the gut microbiome and metabolome of preterm infants.

DESIGN

Cohort study nested within a randomised controlled trial (RCT). Infants across different trial arms were matched on several clinical variables. Bacteria and metabolite compositions of longitudinal stool and urine samples were analysed to investigate the impact of lactoferrin supplementation.

SETTING

Thirteen UK hospitals participating in a RCT of lactoferrin.

PATIENTS

479 infants born <32 weeks' gestation between June 2016 and September 2017.

RESULTS

10 990 stool and 22 341 urine samples were collected. Analyses of gut microbiome (1304 stools, 201 infants), metabolites (171 stools, 83 infants; 225 urines, 90 infants) and volatile organic compounds (314 stools, 117 infants) were performed. Gut microbiome Shannon diversity at 34 weeks corrected age was not significantly different between infants in the lactoferrin (mean=1.24) or placebo (mean=1.06) groups (p=0.11). Lactoferrin receipt explained less than 1% variance in microbiome compositions between groups. Metabolomic analysis identified six discriminative features between trial groups. Hospital site (16%) and postnatal age (6%) explained the greatest variation in microbiome composition.

CONCLUSIONS

This multiomic study identified minimal impacts of lactoferrin but much larger impacts of hospital site and postnatal age. This may be due to the specific lactoferrin product used, but more likely supports the findings of the RCT in which this study was nested, which showed no impact of lactoferrin on reducing rates of sepsis. Multisite mechanistic studies nested within RCTs are feasible and help inform trial interpretation and future trial design.

The faecal metabolome and mycobiome in Parkinson's disease

BACKGROUND

Gut fungal composition and its metabolites have not been assessed simultaneously in Parkinson's disease (PD) despite their potential pathogenic contribution.

OBJECTIVE

To evaluate the faecal metabolome and mycobiome in PD by assessing volatile organic compounds (VOCs) and fungal rRNA.

METHODS

Faecal VOCs from 35 PD patients and two control groups (n = 35; n = 15) were assessed using gas chromatography and mass spectrometry. DNA was extracted from 44 samples: 18S rRNA gene amplicons were prepared and sequenced. Metabolomics, mycobiome and integrated analyses were performed.

RESULTS

Several VOCs were more abundant and short chain fatty acids were less abundant in PD. Hanseniaspora, Kazachstania, uncultured Tremellaceae and Penicillium genera were more abundant, and Saccharomyces less abundant in PD (FDR<0.0007). Torulaspora was associated with PD and two VOCs.

CONCLUSION

PD patients had a distinct metabolome and mycobiome suggesting that fungal dysbiosis may contribute to PD pathogenesis.

Inter-kingdom relationships in Crohn's disease explored using a multi-omics approach

The etiology of Crohn's disease (CD) is multifactorial. Bacterial and fungal microbiota are involved in the onset and/or progression of the disease. A bacterial dysbiosis in CD patients is accepted; however, less is known about the mycobiome and the relationships between the two communities. We investigated the interkingdom relationships, their metabolic consequences, and the changes in the fungal community during relapse and remission in CD.Two cohorts were evaluated: a British cohort (n = 63) comprising CD and ulcerative colitis patients, and controls. The fungal and bacterial communities of biopsy and fecal samples were analyzed, with the fecal volatiles; datasets were also integrated; and a Dutch cohort (n = 41) comprising CD patients and healthy controls was analyzed for stability of the gut mycobiome.A dysbiosis of the bacterial community was observed in biopsies and stool. Results suggest Bacteroides is likely key in CD and may modulate Candida colonization. A dysbiosis of the fungal community was observed only in the Dutch cohort; Malassezia and Candida were increased in patients taking immunosuppressants. Longitudinal analysis showed an increase in Cyberlindnera in relapse. Saccharomyces was dominant in all fecal samples, but not in biopsies, some of which did not yield fungal reads; amino acid degradation was the main metabolic change associated with CD and both bacteria and fungi might be implicated.We have shown that Bacteroides and yeasts may play a role in CD; understanding their role and relationship in the disease would shed new light on the development and treatment of CD.

Oral Ferric Maltol Does Not Adversely Affect the Intestinal Microbiome of Patients or Mice, But Ferrous Sulphate Does

BACKGROUND AND AIMS

Altering dietary ferrous sulphate (FS) consumption exacerbates a murine model of colitis and alters the intestinal microbiome. We investigated the impact of oral ferric maltol (FM) and FS on mice with dextran sodium sulphate (DSS) induced colitis, and the microbiome of patients with iron deficiency.

METHODS

Mice had acute colitis induced, with 2% DSS for 5 days, followed by water. During this period, groups of mice were fed standard chow (200 ppm iron, SC, n = 8), or SC with 200ppm FS supplementation (n = 16, FSS), or SC with 200 ppm FM supplementation (n = 16, FMS). Clinical, pathological and microbiome assessments were compared at days 1 and 10. Fecal bacterial gDNA was extracted and the microbiome assessed by sequencing. Statistical inferences were made using MacQIIME. Principal Coordinates Analysis were used to visualize beta-diversity cluster analysis. Ten patients with IDA were treated with FS, and six with inactive inflammatory bowel disease received FM, supplements for four weeks: pre- and mid-treatment fecal samples were collected: the microbiome was assessed (see above).

RESULTS

In mice, after DSS treatment, there was a decrease in many genera in the SC and FSS groups: Lactobacillales increased in mice that received FMS. In humans, FS treatment led to an increase in five genera, but FM was not associated with any measurable change. The severity of DSS-induced colitis was greater with FSS than FMS.

CONCLUSIONS

This study demonstrates differential and unique influences of ferric maltol and ferrous sulphate supplements on intestinal microbiota. These differences might contribute to the different side effects associated with these preparations.

The Stool Volatile Metabolome of Pre-Term Babies

The fecal metabolome in early life has seldom been studied. We investigated its evolution in pre-term babies during their first weeks of life. Multiple (n = 152) stool samples were studied from 51 babies, all <32 weeks gestation. Volatile organic compounds (VOCs) were analyzed by headspace solid phase microextraction gas chromatography mass spectrometry. Data were interpreted using Automated Mass Spectral Deconvolution System (AMDIS) with the National Institute of Standards and Technology (NIST) reference library. Statistical analysis was based on linear mixed modelling, the number of VOCs increased over time; a rise was mainly observed between day 5 and day 10. The shift at day 5 was associated with products of branched-chain fatty acids. Prior to this, the metabolome was dominated by aldehydes and acetic acid. Caesarean delivery showed a modest association with molecules of fungal origin. This study shows how the metabolome changes in early life in pre-term babies. The shift in the metabolome 5 days after delivery coincides with the establishment of enteral feeding and the transition from meconium to feces. Great diversity of metabolites was associated with being fed greater volumes of milk.

A Comparison of the Colonic Microbiome and Volatile Organic Compound Metabolome of Anoplocephala perfoliata Infected and Non-Infected Horses: A Pilot Study

Simple Summary

In horses, tapeworm infection is associated with specific forms of colic (abdominal pain) that can be life-threatening without surgical treatment. There is growing evidence that intestinal parasites interact with the gut bacteria, and the consequences of these interactions may influence the ability of the host to resist infection and parasite-associated disease. We aimed to compare the intestinal bacteria and the gases produced by metabolic processes in the gut between horses that had varying levels of tapeworms and those with no tapeworm present. Overall, the diversity of gut bacteria was similar in horses with and without tapeworms. There were some decreases in beneficial bacteria in horses with tapeworms, indicating a possible negative consequence of infection. Intestinal gases correlated with some bacteria indicating their functionality and use as potential markers of active bacteria. Our study validates further research investigating tapeworm and gut bacteria interactions in the horse.

Abstract

Anoplocephala perfoliata is a common equine tapeworm associated with an increased risk of colic (abdominal pain) in horses. Identification of parasite and intestinal microbiota interactions have consequences for understanding the mechanisms behind parasite-associated colic and potential new methods for parasite control. A. perfoliata was diagnosed by counting of worms in the caecum post-mortem. Bacterial DNA was extracted from colonic contents and sequenced targeting of the 16S rRNA gene (V4 region). The volatile organic compound (VOC) metabolome of colonic contents was characterised using gas chromatography mass spectrometry. Bacterial diversity (alpha and beta) was similar between tapeworm infected and non-infected controls. Some compositional differences were apparent with down-regulation of operational taxonomic units (OTUs) belonging to the symbiotic families of Ruminococcaceae and Lachnospiraceae in the tapeworm-infected group. Overall tapeworm burden accounted for 7–8% of variation in the VOC profile (permutational multivariate analysis of variance). Integration of bacterial OTUs and VOCs demonstrated moderate to strong correlations indicating the potential of VOCs as markers for bacterial OTUs in equine colonic contents. This study has shown potential differences in the intestinal microbiome and metabolome of A. perfoliata infected and non-infected horses. This pilot study did not control for extrinsic factors including diet, disease history and stage of infection.

Role of circulating endothelial cells in assessing the severity of systemic sclerosis and predicting its clinical worsening

Endothelial damage and fibro-proliferative vasculopathy of small vessels are pathological hallmarks of systemic sclerosis (SSc). The consequence is the detachment of resident elements that become circulating endothelial cells (CECs). The aim of our study was to evaluate the potential of CECs as biomarker in SSc. We enrolled 50 patients with limited cutaneous (lcSSc) and diffuse cutaneous (dcSSc) subset of SSc, who underwent clinical evaluation to establish the organ involvement. CECs were measured by flow-cytometry utilizing a polychromatic panel. An evident difference was observed in CEC counts comparing controls to SSc patients (median 10.5 vs. 152 cells/ml, p < 0.0001) and for the first time, between the two subsets of disease (median lcSSc 132 vs. dcSSc 716 CEC/ml, p < 0.0001). A significant correlation was established between CECs and some SSc clinical parameters, such as digital ulcers, skin and pulmonary involvement, presence of Scl-70 antibodies, nailfold videocapillaroscopy patterns and EUSTAR activity index. After 12 months, CECs correlated with clinical worsening of patients, showing that a number higher than 414 CEC/ml is a strong negative prognostic factor (RR 5.70). Our results indicate that CECs are a direct indicator of systemic vascular damage. Therefore, they can be used as a reliable marker of disease severity.

DNA extraction and amplicon production strategies deeply inf luence the outcome of gut mycobiome studies

Microbial ecology studies are often performed through extraction of metagenomic DNA followed by amplification and sequencing of a marker. It is known that each step may bias the results. These biases have been explored for the study of bacterial communities, but rarely for fungi. Our aim was therefore to evaluate methods for the study of the gut mycobiome. We first evaluated DNA extraction methods in fungal cultures relevant to the gut. Afterwards, to assess how these methods would behave with an actual sample, stool from a donor was spiked with cells from the same cultures. We found that different extraction kits favour some species and bias against others. In terms of amplicon sequencing, we evaluated five primer sets, two for ITS2 and one for ITS1, 18S and 28S rRNA. Results showed that 18S rRNA outperformed the other markers: it was able to amplify all the species in the mock community and to discriminate among them. ITS primers showed both amplification and sequencing biases, the latter related to the variable length of the product. We identified several biases in the characterisation of the gut mycobiome and showed how crucial it is to be aware of these before drawing conclusions from the results of these studies.

Rescue and characterization of a local genotype in Sardinia: Apersorgia nera

Apesorgia nera is an ancient Sardinian grape variety present not only in the old vineyards, but also in courtyards and gardens, throughout the island, mainly in Southern and central Sardinia. This work aims to contribute to the ampelographic, chemical and genetic characterization of this autochthonous variety. The comparison of microsatellite profiles obtained with the main “on line” databases did not allow to identify other vines with the same profile. Apesorgia nera is a variety currently being registered in the National Register of Vine Varieties. The long tradition of cultivation, the presence in historical documents, the qualitative and productive characteristics make it an interesting variety, mainly for the local market.

Antisepsis of the skin before spinal surgery with povidone iodine-alcohol followed by chlorhexidine gluconate-alcohol versus povidone iodine-alcohol applied twice for the prevention of contamination of the wound by bacteria: a randomised controlled trial

AIMS

The aim of this study was to determine whether the sequential application of povidone iodine-alcohol (PVI) followed by chlorhexidine gluconate-alcohol (CHG) would reduce surgical wound contamination to a greater extent than PVI applied twice in patients undergoing spinal surgery.

PATIENTS AND METHODS

A single-centre, interventional, two arm, parallel group randomised controlled trial was undertaken, involving 407 patients who underwent elective spinal surgery. For 203 patients, the skin was disinfected before surgery using PVI (10% [w/w (1% w/w available iodine)] in 95% industrial denatured alcohol, povidone iodine; Videne Alcoholic Tincture) twice, and for 204 patients using PVI once followed by CHG (2% [w/v] chlorhexidine gluconate in 70% [v/v] isopropyl alcohol; Chloraprep with tint). The primary outcome measure was contamination of the wound determined by aerobic and anaerobic bacterial growth from samples taken after disinfection.

RESULTS

The detection of viable bacteria in any one of the samples taken after disinfection (culture-positive) was significantly lower in the group treated with both PVI and CHG than in the group treated with PVI alone (59 (29.1%) versus 85 (41.7%), p = 0.009; odds ratio 0.574; 95% confidence interval, 0.380 to 0.866).

CONCLUSIONS

Antisepsis of the skin with the sequential application of PVI and CHG more effectively reduces the contamination of a surgical wound than PVI alone. Cite this article: Bone Joint J 2017;99-B:1354-65.

Multidrug resistance P-glycoprotein dampens SR-BI cholesteryl ester uptake from high density lipoproteins in human leukemia cells

Tumor cells are characterised by a high content of cholesterol esters (CEs), while tumor-bearing patients show low levels of high-density lipoproteins (HDLs). The origin and significance of high CE levels in cancer cell biology has not been completely clarified. Recent evidence that lymphoblastic cells selectively acquire exogenous CE from HDL via the scavenger receptor SR-BI has drawn attention to the additional membrane proteins involved in this pathway. P-glycopotein-MDR1 (P-gp) is a product of the MDR1 gene and confers resistance to antitumor drugs. Its possible role in plasma membrane cholesterol trafficking and CE metabolism has been suggested. In the present study this aspect was investigated in a lymphoblastic cell line selected for MDR1 resistance. CEM were made resistant by stepwise exposure to low (LR) and high (HR) doses of vincristine (VCR). P-gp activity ((3)H-vinblastine), CE content, CE and triglycerides (TG) synthesis ((14)C-oleate), neutral lipids and Dil-HDL uptake (fluorescence), SR-BI, ABCA1 and P-gp protein expression (western blotting) were determined. To better evaluate the relationship between CE metabolism and P-gp activity, the ACAT inhibitor Sandoz-58035 and the P-gp inhibitors progesterone, cyclosporine and verapamil were used. CE content and synthesis were similar in the parental and resistant cells. However, in the latter population, SR-BI protein expression increased, whereas CE-HDL uptake decreased. These changes correlated with the degree of VCR-resistance. As well as reverting MDR1-resistance, the inhibitors of P-gp activity induced the CE-HDL/SR-BI pathway by reactivating membrane cholesterol trafficking. Indeed, CE-HDL uptake, SRBI expression and CE content increased, whereas there was a decrease in cholesterol esterification. These results demonstrated that P-gp overexpression impairs anticancer drug uptake as well as the SR-BI mediated selective CE-HDL uptake. This suggests that these membrane proteins act in an opposite manner on the same transport mechanism. Therefore, the dampening activity of P-gp in this pathway and its reversal by P-gp inhibitors open new strategies for antitumor therapy in drug-resistant tumors.

High-density lipoprotein contribute to G0-G1/S transition in Swiss NIH/3T3 fibroblasts

High density lipoproteins (HDLs) play a crucial role in removing excess cholesterol from peripheral tissues. Although their concentration is lower during conditions of high cell growth rate (cancer and infections), their involvement during cell proliferation is not known. To this aim, we investigated the replicative cycles in synchronised Swiss 3T3 fibroblasts in different experimental conditions: i) contact-inhibited fibroblasts re-entering cell cycle after dilution; ii) scratch-wound assay; iii) serum-deprived cells induced to re-enter G1 by FCS, HDL or PDGF. Analyses were performed during each cell cycle up to quiescence. Cholesterol synthesis increased remarkably during the replicative cycles, decreasing only after cells reached confluence. In contrast, cholesteryl ester (CE) synthesis and content were high at 24 h after dilution and then decreased steeply in the successive cycles. Flow cytometry analysis of DiO-HDL, as well as radiolabeled HDL pulse, demonstrated a significant uptake of CE-HDL in 24 h. DiI-HDL uptake, lipid droplets (LDs) and SR-BI immunostaining and expression followed the same trend. Addition of HDL or PDGF partially restore the proliferation rate and significantly increase SR-BI and pAKT expression in serum-deprived cells. In conclusion, cell transition from G0 to G1/S requires CE-HDL uptake, leading to CE-HDL/SR-BI pathway activation and CEs increase into LDs.

Preventive treatments for breast cancer: recent developments

Breast cancer is a burden for western societies, and an increasing one in emerging economies, because of its high incidence and enormous psychological, social, sanitary and economic costs. However, breast cancer is a preventable disease in a significant proportion. Recent developments in the armamentarium of effective drugs for breast cancer prevention (namely exemestane and anastrozole), the new recommendation from the National Institute for Health and Care Excellence to use preventative drugs in women at high risk as well as updated Guidelines from the US Preventive Services Task Force and the American Society of Clinical Oncology should give renewed momentum to the pharmacological prevention of breast cancer. In this article we review recent major developments in the field and examine their ongoing repercussion for breast cancer prevention. As a practical example, the potential impact of preventive measures in Spain is evaluated and a course of practical actions is delineated.

An uncommon association of antiphospholipid syndrome, selective IgA deficiency and resistant-to-treatment relapsing polychondritis: efficacy of infliximab

Autoimmune complications in the context of primary immunodeficiency diseases represent a well-known phenomenon, and this is widely recognized also for Selective Immunoglobulin A deficiency (IgAD), the most common primary antibody deficiency (PAD). Relapsing polychondritis (RP) is a rare immune-mediated, difficult to treat, disorder in which the cartilaginous tissues are the target for inflammation and damage. Ocular inflammatory manifestations in RP are frequent and often sight-threatening. Antiphospholipid syndrome (APS) is an acquired prothrombotic state related to circulating autoantibodies against phospholipids and/or their cofactors. Rare reports of APS associated to RP, PAD and APS or PAD and RP are available.

TYRP1 mRNA expression in melanoma metastases correlates with clinical outcome

Background:

Clinical outcome of patients with high-risk melanoma cannot be reliably predicted on the basis of classical histopathological examination. Our study aimed to determine in melanoma metastases a gene expression profile associated with patient survival, and to identify and validate marker(s) of poor clinical outcome.

Methods:

Skin and lymph node metastases from melanoma patients (training population) were used to identify candidate prognostic marker(s) based on DNA microarray analysis. Additional skin metastases (validation population) were used to assess the prognostic value of the first ranked gene by real-time PCR.

Results:

We performed microarray analysis in the training population and generated a list of 278 probe sets associated with a shorter survival. We used the first ranked gene, tyrosinase-related protein 1 (TYRP1), further measured its expression in the validation population by real-time PCR and found it to be significantly correlated with distant metastasis-free survival (DMFS), overall survival (OS) and Breslow thickness. We also found that it was fairly well conserved in the course of the disease regardless of the delay to metastasis occurrence. Finally, although Tyrp1 protein (immunohistochemistry (IHC)) was only detected in about half of the samples, we showed that its expression also correlated with Breslow thickness.

Conclusion:

Our data indicate that TYRP1 mRNA expression level, at least in skin metastases, is a prognostic marker for melanoma, and is particularly useful when prognostic pathology parameters at the primary lesion are lacking. Its conserved expression further supports its use as a target for therapy.

Pegfilgrastim and daily granulocyte colony-stimulating factor: patterns of use and neutropenia-related outcomes in cancer patients in Spain--results of the LEARN Study

Daily granulocyte colony-stimulating factors [(G-CSFs); e.g. filgrastim, lenograstim] are frequently used to reduce the duration of chemotherapy-induced neutropenia (CIN) and the incidence of febrile neutropenia (FN) in cancer patients. A pegylated formulation of filgrastim, pegfilgrastim, which is administered once per cycle, was introduced in Spain in 2003. LEARN was a multi-centre, retrospective, observational study in Spain comparing patterns of use of daily G-CSF and pegfilgrastim, and CIN-related outcomes in adults with non-myeloid malignancies receiving myelosuppressive chemotherapy. Outcome measures were the percentage of patients receiving G-CSF for primary prophylaxis versus secondary prophylaxis/treatment, duration of treatment with G-CSF and incidence of CIN-related complications. Medical records from consecutive patients with documented pegfilgrastim (n = 75) or daily G-CSF (n = 111) use during 2003 were included. The proportion of patients receiving primary or secondary prophylaxis was comparable between the pegfilgrastim (39 and 48% respectively) and daily G-CSF (40 and 48% respectively) groups. However, there was a trend towards less frequent use to treat a neutropenic event such as FN or neutropenia in the pegfilgrastim group (17 versus 30% with daily G-CSF). Chemotherapy-induced neutropenia-related complications were less frequent in patients receiving pegfilgrastim (e.g. FN 11 versus 24% with daily G-CSF). This is the first study to show the potential benefits of pegfilgrastim over daily G-CSF in Spanish clinical practice.

Cost of febrile neutropenia management in cancer patients in Spain

6089

Background: Febrile neutropenia (FN), a dose-limiting event for many myelosuppressive chemotherapy (CT) regimens, often causes subsequent CT dose delays (DD) and reductions (DR), lengthens hospital stay and increases monitoring, diagnostic and treatment costs. No studies are known to date on economic costs of FN in common clinical practice in Spain. Methods: This is a multicentre, retrospective, observational chart review of adult patients with breast cancer, lung cancer or non-Hodgkin’s lymphoma (NHL) who suffered from at least one FN episode related to cytotoxic CT from 16 Spanish hospitals. Resource use and subsequent costs including days of hospitalization, number of RBC transfusions, number and type of complementary tests, use of colony-stimulating factors (CSF), antibiotics and other drugs to manage FN were assessed. Potential impact of FN on planned CT dose and/or schedule was also analysed. P-value was obtained by one-way ANOVA using the Bonferroni correction. Results: A total of 194 medical charts including 238 documented FN episodes were reviewed. Women, 59.8%; age > 60 yrs, 49.5%; breast cancer, 43% (83% treated with taxane or anthracycline-based CT); lung cancer, 22% (95.5% treated with platinum-based CT); NHL, 35% (58.2% treated with CHOP-like CT). Hospitalization due to FN lasted a median of 7 days. During the episode, 32.3% of pts needed 1 or more RBC transfusions, 97.9% required a blood test and 87% a blood culture. CSFs were used in 67.6% of pts. All pts were treated with antibiotics and 78.2% with other drugs. 58.4% of FN episodes had an impact on planned CT dose and/or schedule: DR was observed in 34.9% of cases, DD in 28% and CT withdrawal in 14.7%. Conclusions: Main drivers of cost of FN are hospitalization and antibiotic treatment. FN is more costly in NHL pts than breast or lung pts (statistically significant in lung pts). FN episodes have a relevant impact on planned CT dose and/or schedule. In each row statistically significant differences ( p<0.05) were obtained between values with the same letter.

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Epirubicin-cyclophosphamide adjuvant chemotherapy plus tamoxifen administered concurrently versus sequentially: randomized phase III trial in postmenopausal node-positive breast cancer patients. A GEICAM 9401 study

BACKGROUND

A prospective randomized clinical trial was implemented to assess whether the concomitant or the sequential addition of tamoxifen to chemotherapy provides improved clinical benefit in the adjuvant treatment of breast cancer in postmenopausal patients.

PATIENTS AND METHODS

Four-hundred and eighty-five patients with node-positive operable disease were randomized to receive tamoxifen (20 mg/day) concomitantly (CON) or sequentially (SEQ) to EC chemotherapy (epirubicin 75 mg/m(2) + cyclophosphamide 600 mg/m(2) on day 1, every 21 days for four cycles).

RESULTS

In the 474 fully evaluable patients there were 96 events; eight being second neoplasms and 88 being related to the breast cancer. Of these, 48 of 88 occurred in the CON arm and 40 of 88 in the SEQ arm. The Kaplan-Meier estimation of disease-free survival (DFS) at 5 years was 70% in the CON and 75% in the SEQ group (log-rank test, P = 0.43). Adjusted hazard ratio for treatment was 1.11 (95% confidence interval 0.71-1.73; P = 0.64).

CONCLUSION

This study fails to show an advantage of one treatment arm over the other, but a trend, albeit non-significant, appears to favor the sequential addition of tamoxifen to epirubicin + cyclophosphamide and, as such, warrants further investigation.

Synthetic undecapeptide (NTX10-20) of noxiustoxin blocks completely the I(A) potassium currents of cerebellum granular cells

Native noxiustoxin (NTX) and synthetic peptides corresponding to its primary sequence, from positions 1-9, 1-14, 1-20, 10-20, 21-39 and 30 39, were prepared and assayed on the K+ currents of cerebellum granular cells, using the patch-clamp technique in the whole-cell configuration system. Native toxin has a reversible inhibitory effect (IC50 = 360 nM), whereas synthetic peptides NTXI-20 and NTX1-9 had a half-effective dose IC50 of approximately 2 and 10 microM, respectively, which correlates with their biological effects in vivo. Synthetic peptide NTX10-20 was quite remarkable in having a preference for the IA current, which was completely inhibited at high peptide concentration. The effects of the other peptides (NTXI 14, NTX21-39 and NTX30-39), although positive and reversible, required higher concentrations (50 200 microM) to block both currents, suggesting no affinity or, at least, much lower specificity for the channels responsible for the potassium currents in the granular cells studied.

Phase II study of ifosfamide plus vinorelbine in metastatic breast cancer patients previously treated with combination chemotherapy

Forty-six patients were included in a phase II study to evaluate the response rate and toxicity of a combination of ifosfamide and vinorelbine in metastatic breast cancer patients previously treated with one or more regimens of chemotherapy. Treatment consisted of ifosfamide 1.6 g/m(2) IV days 1-3 (with mesna) and vinorelbine 25 mg/m(2) IV days 1 and 8, every 3 weeks up to 6 cycles. The median age was 55 years (range 40-76), the World Health Organization (WHO) performance status was 0-1 in 93% of the patients and 2 in the remaining 7%. In all, 43% had received two or more previous lines of chemotherapy, and 91% had been treated with anthracyclines. Forty-four patients were evaluable for response, and all patients for toxicity. The overall response rate was 36.4% [95% confidence interval (CI) 22.4-52.2]. Stabilization was observed in 20.4% and progression in 43.2%. The median time to progression was 25 weeks (95% CI 14-36). Median relative dose intensity (=actual received dose intensity/planned dose intensity) was 0.99 for ifosfamide and 0. 80 for vinorelbine. The main toxicity was hematological, with 63% of the patients experiencing grade 3-4 neutropenia. With a moderate toxicity, this is an active regimen that may be taken into consideration in pretreated metastatic breast cancer patients when further chemotherapy is indicated.

A randomized phase II trial of 5-fluorouracil, with or without human interferon-beta, for advanced colorectal cancer

This study compared the efficacy and safety of 5-fluorouracil (5-FU) monotherapy to that of 5-FU combined with natural human interferon-beta (IFN-beta) in patients with unresectable, advanced colorectal carcinoma. Forty-nine chemotherapy-naive patients were randomized to 5-FU alone or to the combination. All patients received 750 mg m(-2) day(-1) 5-FU for 5 days by continuous intravenous (i.v.) infusion, followed after day 15 by a weekly i.v. bolus of 750 mg m(-2). IFN-beta was injected intramuscularly three times weekly at 9 M IU. Treatment continued for 52 weeks, or until disease progression or intolerable toxicity. Clinical endpoints were tumor response, time to progression, survival and toxicity. The addition of IFN-3 to 5-FU significantly improved response rate (33.3% vs 4.5% for evaluable patients; P = 0.021), time to progression (median 7.2 vs 4.2 months; P = 0.0435), and survival time (median 15.9 vs 7.2 months; P = 0.038) without significantly increasing toxicity compared to 5-FU alone. Cumulative 5-FU dose was higher with combined therapy (P < 0.001): more patients receiving monotherapy discontinued treatment because of disease progression. Fever was more frequent with combined therapy (P = 0.008); there were no other differences in toxicity. The only grade IV toxicity observed was neutropenia (two patients per group). A randomized phase III trial has been initiated to confirm the synergy between 5-FU and IFN-beta.

Potentiation of gentamicin nephrotoxicity in the rat by infusion of aprotinin

The present study was undertaken to examine a possible effect of aprotinin, a 6.5-kDa polypeptide with an inhibitory effect on proteolysis, on aminoglycoside nephrotoxicity. Experimental animals (female Sprague-Dawley rats, 175-200 g body wt) were treated for 4 days with 40 mg/kg gentamicin given ip at 12-hr intervals. Aprotinin (40,000 kIU per animal) was infused i.v. over a period of 8 days, using subcutaneously implanted miniosmotic pumps. In protocol A, infusion pumps were placed 4 days before starting gentamicin treatment. In protocol B, pumps were implanted 15-18 hr prior to first gentamicin administration. In addition to rats exposed to both gentamicin and aprotinin (GAP), animals were treated with gentamicin ip+saline i.v. (G), saline ip+aprotinin i.v. (AP), or received only saline by both routes of administration (C). All rats were terminated 4 days after the end of gentamicin dosing. One hour before sacrifice, 200 microCi of [3H]thymidine was given ip to each animal in order to monitor cell turnover in renal tissue. The kidneys were analyzed with respect to (i) histopathological alterations and renal dysfunction, (ii) aminoglycoside tissue accumulation, and (iii) tubular regeneration (measurement of cell proliferation). In animals receiving aprotinin alone, histological examination of renal cortex on paraffin sections disclosed mild tubular injury with focal cell necrosis. In plastic-embedded tissue, proximal tubule epithelium was characterized by the presence of numerous inclusions densely stained with toluidine blue. At the ultrastructural level, these inclusions appeared filled with amorphous electron-dense material. In gentamicin-treated animals, cortical drug accumulation reached values higher than 0.3 mg/g renal tissue, but a significant 30-40% decrease of gentamicin accumulation was noted in GAP groups, compared to G groups. Histological examination of renal cortex (paraffin sections) revealed the development of acute tubular necrosis in both G and GAP groups. Tubular injury was accompanied by mild renal dysfunction, as shown by the level of serum creatinine which was increased almost 3-fold in the G group, compared to C and AP groups. Aprotinin infusion produced a further increase of serum creatinine, particularly in protocol A where it was 72% higher for the GAP group than for the G group. In both G and GAP groups, postnecrotic tubular regeneration was evidenced by determining the rate of DNA synthesis and the frequency of S-phase cells in renal cortex. Both methods gave consistent results and showed a 8- to 13-fold increase of cell proliferation in groups receiving gentamicin alone, compared to C groups.(ABSTRACT TRUNCATED AT 400 WORDS)

Gamma radiation-induced differentiation on human neuroblastoma cells in culture

We have studied the effect of gamma radiation on differentiation in neuroblastoma cell lines AF8 and SJ-N-KP. Growth inhibition and morphological and biochemical differentiation have been examined following radiation exposure to 1-10 Gy. Gamma radiation induced marked growth inhibition and morphological differentiation in a dose-and time-dependent manner in both cell lines, and induced biochemical differentiation in AF8 cells.