Immune modulation via dendritic cells by the effect of Thymosin-alpha-1 on immune synapse in HCMV infection.

Tα1 (Thymosin-alpha-1) is a thymus-derived hormone that has been demonstrated to be effective on diverse immune cell subsets. The objective of this study was to determine the in vitro immunomodulatory effect of Tα1 in human cytomegalovirus (HCMV) infection. Dendritic cells (DCs) were isolated from peripheral blood mononuclear cells (PBMCs) by negative selection and cultured in the presence or absence of Tα1. The immunophenotyping of DCs was characterised by multiparametric flow cytometry assessing CD40, CD80, TIM-3 and PDL-1 markers, as well as intracellular TNFα production. Then, autologous CD4+ or CD8+ T-Lymphocytes (TLs) isolated by negative selection from PBMCs were co-cultured with DCs previously treated with Tα1 in the presence or absence of HCMV. Intracellular TNFα, IFNγ, IL-2 production, CD40-L and PD-1 expression were assessed through immunophenotyping, and polyfunctionality in total TLs and memory subsets were evaluated. The results showed that Tα1 increased CD40, CD80, TIM-3 and TNFα intracellular production while decreasing PDL-1 expression, particularly on plasmacytoid dendritic cells (pDCs). Therefore, Tα1 modulated the production of TNFα, IFNγ and IL-2 in both total and memory subsets of CD4+ and CD8+ TLs by upregulating CD40/CD40-L and downregulating PDL-1/PD-1 expression. Our study concludes that Tα1 enhances antigen-presenting capacity of DCs, improves TLs responses to HCMV infection, and enhances the polyfunctionality of CD8+ TLs. Consequently, Tα1 could be an alternative adjuvant for use in therapeutic cell therapy for immunocompromised patients.

Outcomes of an enhanced recovery after radical cystectomy program in a prospective multicenter study: compliance and key components for success.

OBJECTIVE: To investigate the effect of an Enhanced Recovery After Surgery (ERAS) program on complications and length of stay (LOS) after radical cystectomy (RC) and to assess if the number and type of components of ERAS play a key role on the decrease of surgical morbidity. MATERIALS AND METHODS: We analyzed the data of 277 patients prospectively recruited in 11 hospitals undergoing RC initially managed according to local practice (Group I) and later within an ERAS program (Group II). Two main outcomes were defined: 90-day complications rate and LOS. As secondary variables we studied 90-day mortality, 30-day readmission and transfusion rate. RESULTS: Patients in Group II had a higher use of ERAS measures (98.6%) than those in Group I (78.2%) (p < 0.05). Patients in Groups I and II experienced similar complications (70.5% vs. 66%, p = 0.42). LOS was not different between Groups I and II (12.5 and 14 days, respectively, p = 0.59). The risk of having any complication decreases for patients having more than 15 ERAS measures adopted [RR = 0.815; 95% confidence interval (CI) 0.667-0.996; p = 0.045]. Avoidance of transfusion and nasogastric tube, prevention of ileus, early ambulation and a fast uptake of a regular diet are independently associated with the absence of complications. CONCLUSIONS: Complications and LOS after RC were not modified by the introduction of an ERAS program. We hypothesize that at least 15 measures should be applied to maximize the benefit of ERAS.

Toll-Like Receptor 7 (TLR-7) and TLR-9 Agonists Improve Hepatitis C Virus Replication and Infectivity Inhibition by Plasmacytoid Dendritic Cells.

Plasmacytoid dendritic cells (pDCs) are innate immune cells with high antiviral activity triggered by Toll-like receptor 7 (TLR-7) and TLR-9 stimulation. Moreover, they are important mediators between innate and adaptive immunity. Although nowadays there is available an effective therapeutic arsenal against hepatitis C virus (HCV), a protective vaccine is not available. We have analyzed the pDCs' response to HCV infection in a hepatitis C virus (HCV)-Huh7.5 virus-cell system, which allows completion of the virus infectious cycle. pDCs were cocultured following human immunodeficiency virus (HIV) aldrithiol-2 (AT-2 [TLR-7 agonist]) inactivation and CpG (TLR-9 agonist) stimulation. We employed three virus derivatives-wild-type Jc1, interferon (IFN)-resistant virus IR, and high-replicative-fitness virus P100-in order to explore additional IFN-α-related virus inhibition mechanisms. pDCs inhibited HCV infectivity and replication and produced IFN-α. After TLR-7 and TLR-9 stimulation, inhibition of infectivity and IFN-α production by pDCs were enhanced. TLR-7 stimulation drove higher TNF-related apoptosis-inducing ligand (TRAIL) expression in pDCs. Additionally, TLR-7- and TLR-9-stimulated pDCs exhibited a mature phenotype, improving the antigen presentation and lymph node homing-related markers. In conclusion, pDCs could serve as a drug target against HCV in order to improve antiviral activity and as an enhancer of viral immunization.IMPORTANCE We implemented a coculture system of pDCs with HCV-infected hepatoma cell line, Huh7.5. We used three HCV derivatives in order to gain insight into pDCs' behavior against HCV and associated antiviral mechanisms. The results with this cell coculture system support the capacity of pDCs to inhibit HCV replication and infectivity mainly via IFN-α, but also through additional mechanisms associated with pDC maturation. We provided evidence that TLR agonists can enhance antiviral pDCs' function and can induce phenotypic changes that may facilitate the interplay with other immune cells. These findings suggest the possibility of including TLR agonists in the strategies of HCV vaccine development.

Surgery for pancreatic ductal adenocarcinoma.

Surgical resection is the only potentially curative option in the treatment of pancreatic ductal adenocarcinoma. Preoperative radiological imaging allows to rule out the presence of metastases. Three resectability categories are established based on the radiological findings depending on the degree of contact between the tumor and the blood vessels. Histological confirmation of malignancy is only required in cases of borderline or non-resectable tumors, prior to neoadjuvant treatment initiation. Diagnostic laparoscopy is recommended in the presence of large tumors of the body or tail and in borderline tumors to explore the possibility of resection and to apply treatment with curative intent, as well as in those cases with high level of biomarkers to rule out peritoneal involvement. Prior to surgery preoperative nutritional measures as well as endoscopic biliary drainage can be applied to optimize patient's conditions. Cephalic pancreaticoduodenectomy is the recommended surgical technique in tumors located in the head of the pancreas. The benefits from pyloric preservation, type or reconstruction (one vs. two loops), type of anastomosis (pancreaticojejunostomy vs. pancreaticogastrostomy), intraoperative biopsy of the pancreatic resection margin or the use of intraperitoneal drainages are inconclusive. Total pancreatectomy and/or portal resection should only be performed in particular cases; however, arterial resections have shown no benefits. Radical antegrade modular pancreaticosplenectomy, that can be performed laparoscopically, is the technique used for those tumors located in the pancreatic body-tail.

Consensus guidelines for diagnosis, treatment and follow-up of patients with pancreatic cancer in Spain.

The management of patients with pancreatic cancer has advanced over the last few years. We convey a multidisciplinary group of experts in an attempt to stablish practical guidelines for the diagnoses, staging and management of these patients. This paper summarizes the main conclusions of the working group. Patients with suspected pancreatic ductal adenocarcinoma should be rapidly evaluated and referred to high-volume centers. Multidisciplinary supervision is critical for proper diagnoses, staging and to frame a treatment plan. Surgical resection together with chemotherapy offers the highest chance for cure in early stage disease. Patients with advanced disease should be classified in treatment groups to guide systemic treatment. New chemotherapeutic regimens have resulted in improved survival. Symptomatic management is critical in this disease. Enrollment in a clinical trial is, in general, recommended.

Validation of the HIV Tropism Test TROCAI Using the Virological Response to a Short-Term Maraviroc Monotherapy Exposure.

TROCAI is a phenotypic tropism test developed using the virological response to a short-term exposure to maraviroc monotherapy (Maraviroc Clinical Test [MCT]). It was found that with TROCAI, a cutoff of <0.5% of dual/mixed viruses was needed to predict R5 HIV tropism. Here, we have validated TROCAI, using this cutoff, in a new cohort of 42 patients, finding a very high concordance between TROCAI and MCT (98%), and a good concordance (71 to 87%) with other genotypic/phenotypic methods.

Canine mammary tumors: a review and consensus of standard guidelines on epithelial and myoepithelial phenotype markers, HER2, and hormone receptor assessment using immunohistochemistry.

Although there have been several studies on the use of immunohistochemical biomarkers of canine mammary tumors (CMTs), the results are difficult to compare. This article provides guidelines on the most useful immunohistochemical markers to standardize their use and understand how outcomes are measured, thus ensuring reproducibility of results. We have reviewed the biomarkers of canine mammary epithelial and myoepithelial cells and identified those biomarkers that are most useful and those biomarkers for invasion and lymph node micrometastatic disease. A 10% threshold for positive reaction for most of these markers is recommended. Guidelines on immunolabeling for HER2, estrogen receptors (ERs), and progesterone receptors (PRs) are provided along with the specific recommendations for interpretation of the results for each of these biomarkers in CMTs. Only 3+ HER2-positive tumors should be considered positive, as found in human breast cancer. The lack of any known response to adjuvant endocrine therapy of ER- and PR-positive CMTs prevents the use of the biological positive/negative threshold used in human breast cancer. Immunohistochemistry results of ER and PR in CMTs should be reported as the sum of the percentage of positive cells and the intensity of immunolabeling (Allred score). Incorporation of these recommendations in future studies, either prospective or retrospective, will provide a mechanism for the direct comparison of studies and will help to determine whether these biomarkers have prognostic significance. Finally, these biomarkers may ascertain the most appropriate treatment(s) for canine malignant mammary neoplasms.

Establishment and characterization of a canine xenograft model of inflammatory mammary carcinoma.

Canine inflammatory mammary cancer (IMC) and human inflammatory breast cancer (IBC) are the most aggressive form of mammary/breast cancer. Both species naturally develop it, sharing epidemiological, clinical and histological characteristics. Thus, IMC has been suggested as a model to study the human disease. We have developed the first IMC xenograft model in SCID mice. Xenografts reproduced the histological features from the primary tumor, were highly aggressive and showed dermal tumor emboli, distinctive hallmarks of IMC/IBC. This model was hormone receptors positive and HER2 negative. Our findings showed that estrogens and androgens are locally produced in tissues. Factors related to tumor vascularization showed positive expression and xenografts with the highest expression of all analyzed vascular factors had the highest rate of tumor proliferation. The role of steroid hormones and the angio/lymphangiogenic properties found in this model, provide additional knowledge for future interventions in the diagnosis, treatment and prevention of the disease.

[Description of tuberculosis outbreak and usefulness of mediastinal ultrasound]. / Descripción de un brote de tuberculosis y utilidad de la ecografía mediastínica.

OBJECTIVES: Describe a school outbreak of tuberculosis and compare the features with other outbreaks. Propose mediastinal ultrasound as an aid in its diagnosis and monitoring. PATIENTS AND METHODS: Retrospective descriptive study of the transmission of tuberculosis infection in a micro-epidemic. Infection criteria: Mantoux ≥ 5mm, asymptomatic patient, with normal radiological, microbiological and analytical studies. Disease criteria: Mantoux ≥ 5mm and any of the above pathological studies. Mediastinal ultrasound was used as a complementary method of chest radiography (CXR). Computed tomography (CT) as the combined result of ultrasound and CXR was inconclusive. RESULTS: Seventeen out of 412 students were infected and 16 with tuberculosis disease. In addition, 4 out-school contacts were diagnosed of tuberculosis. CLINICAL MANIFESTATIONS: one erythema nodosum, one Henoch-Schönlein purpura, twelve with cough and fever nine. CXR results in patients: 3 normal, 7 inconclusive, and 10 with the following findings: 2 pneumonia, 2 pulmonary atelectasis, 2 primary complexes, 4 patients only with lymphadenopathy. All patients with normal or indeterminate CXR showed mediastinal lymphadenopathy visualized on ultrasound but 3 demonstrated by CT. Microbiological isolation: 6 cases (31%). CONCLUSIONS: The number of infected patients was higher compared to other outbreaks There is great variability in the diagnostic approach to tuberculosis micro-epidemics. It is complex to differentiate between infection and disease. The clinical, laboratory and CXR are nonspecific. There are patients with normal CXR, pathological ultrasound and microbiological isolation. Mediastinal ultrasound can play an important role in the diagnosis and management of tuberculosis disease.

Atrial Fibrillation and Stroke Risk After Coronary Artery Bypass Grafting Surgery.

Background: The present multicentre study was aimed at determining the effect of preoperative atrial fibrillation (preop-AF) as stroke risk factor in coronary artery bypass graft surgery (CABG) during the perioperative period. Methods: Patients undergoing isolated CABG surgery were enrolled from 21 Spanish centers. Baseline variables related with perioperative stroke risk were recorded and analysed. The Northern New England Cardiovascular Disease Study Group (NNECVDSG) stroke risk schema was used to stratify stroke risk and compare predicted vs observed neurologic outcomes in this study. Results: 26347 patients were enrolled in the study. Prevalence of preop-AF was 4.2%, and was associated significantly with major cardiovascular comorbidities. The stroke rate was 1.38% (365 strokes), and it was slightly higher for patients with preop-AF vs non preop-AF, 1.82% vs 1.36%, p = 0.2. NNECVDSG schema showed good predictive ability calculating the area under the receiver operating characteristic curve (c-statistic 0.696; 95% CI 0.668 to 0.723). To investigate the associations of baseline preoperative variables with perioperative CABG-stroke a logistic regression model was performed. Preop-AF impact on perioperative stroke was lower that other variables. Preop-AF did not show an adverse impact in the quartiles groups according to NNECVDSG Stroke Risk Index. Conclusion: Risk of perioperative stroke in isolated CABG surgery patients is not significantly increased by preop-AF.

Capillary liquid chromatography with diode array and mass spectrometry detection for heterocyclic aromatic amine determination in ready-to-eat food treated with electron-beam irradiation.

In the present paper, we have developed a capillary liquid chromatography with MS detection for the determination at ngg⁻¹ levels of four heterocyclic aromatic amines (MeIQx, norharman, harman and harmine), a group of mutagenic and carcinogenic compounds that can potentially be produced in protein-rich food during processing operations. They have been determined in commercial ready-to-eat (RTE) smoked salmon and soft cheese treated with E-beam irradiation. On the basis of experimental design studies and operating conditions of MS detector, best chromatographic conditions were obtained using a Luna® C¹8 capillary column (150 mm × 0.3 mm I.D.) with a mixture of acetonitrile-ammonium formate 5 mM pH 3.6 buffer (13:87, v/v) as mobile phase. To improve sensitivity, large injection volumes (20 µL) and injection solutions of low elution strength were employed. Sample preparation procedure included a previous treatment with 1M NaOH, followed by two solid-phase extraction steps; firstly on diatomaceous earth and then on mixed-mode cartridges. Heterocyclic amines were detected neither in irradiated and in non-irradiated samples, indicating that they were not formed by the radiation effect even at doses higher than those indicated in the Food Safety Objective established by regulatory agencies. RTE food samples were spiked at concentration levels in the range 10-30 ngg⁻¹. Recoveries higher than 85% (n=3 for each spiked level) were obtained, showing the effectiveness of the proposed methodology.

Consensus on the treatment of pancreatic cancer in Spain.

Pancreatic cancer (PC) represents one of the greatest oncological challenges of our century, due to its high mortality and incidence. A group of Spanish experts in PC treatment reviewed data available on different therapeutic combinations and established consensus on what would be the best strategy in PC management, depending on the stage of the disease. Surgery with complete resection may produce 5-year survival rates of 18-24%, but definitive control is still precarious. In the absence of consensus, the best evidence suggests that adjuvant chemotherapy with gemcitabine for 6 months using the CONKO-001 regime is the treatment of choice after resection of PC for patients with acceptable functional status. This group recommends chemoradiotherapy (CT-RT) in patients with factors for poor loco-regional prognosis. However, chemotherapy is an option for the treatment of locally advanced PC in patients with good general status and in the absence of metastatic disease the recommended treatment is CT-RT followed by gemcitabine-based chemotherapy. A period of chemotherapy followed by consolidation CT-RT may be appropriate, as it allows selection of patients with locally advanced disease who may benefit most from combined treatment. Erlotinib combined with gemcitabine shows significant survival improvement in PC and must be considered an option in the first-line treatment of advanced and metastatic PC. The gemcitabine-erlotinib combination is proposed as the standard treatment for metastatic PC in patients with PS=/>2. In patients with PS<2, gemcitabine-erlotinib is recommended as the first-line treatment option, supported by a maximum degree of evidence, without ruling out other options, such as gemcitabine-oxaliplatin, gemcitabine-capecitabine or gemcitabine alone.

Free D-amino acids determination in ready-to-eat cooked ham irradiated with electron-beam by indirect chiral HPLC.

Potential racemization of L-amino acids (AA) in ready-to-eat (RTE) cooked ham after hygienization by electron-beam irradiation between 1 and 8kGy was studied. An indirect chiral method based on the derivatization reaction of AA with o-phthaldialdehyde and N-acetyl-L-cysteine followed by reversed-phase HPLC and fluorimetric detection was applied to detect ten enantiomeric pairs of free AA (Asp, Ser, Thr, Ala, Tyr, Val, Trp, Phe and Leu). Five of the D-AA were not found in any of the samples analyzed; the other five remaining D-AA (D-Asp, D-Ser, D-Ala, D-Val and D-Leu) were detected both in irradiated and non-irradiated cooked ham samples, their content being in the range 1.25-13.79µg/g. Although significant differences appeared for a few of the samples and doses, no positive correlation between the D-AA content and the irradiation doses was observed. Therefore, the electron-beam irradiation technique could be useful for sanitation of packed RTE cooked ham at doses allowed by WHO and EU, since it remains chemically safe to eat.

Determination of carbamate, phenylurea and phenoxy acid herbicide residues by gas chromatography after potassium tert-butoxide/dimethyl sulphoxide/ethyl iodide derivatization reaction.

The usefulness of the potassium tert-butoxide/dimethyl sulphoxide/ethyl iodide reaction with carbamate and phenylurea herbicides, and its application to phenoxy acids as a way to prevent hazards and toxicity of the sodium hydride/dimethyl sulphoxide/methyl iodide reaction was studied. Using factorial design optimization of this reaction was carried out. A solid-phase extraction method using dimethyl sulphoxide as eluent on-line with this reaction was developed to determine these herbicides in water samples by gas chromatography-mass spectrometry. Relative standard deviation values were lower than 10% for most of the herbicides in multicomponent trace determinations. Detection limits were in the 0.110-0.652 ng L(-1) concentration range. The validity of the method was confirmed by recovery studies from natural water samples.

Determination of heterocyclic aromatic amines by capillary high-performance liquid chromatography with diode array detection in ready-to-eat cooked ham treated with electron-beam irradiation.

Heterocyclic aromatic amines (HAs) are a group of mutagenic and carcinogenic substances present in significant amounts in cooked meat and fish that can potentially be formed during food processing operations. This paper proposes a capillary liquid chromatography method with diode array detection for the trace-level determination of three HAs, namely, MeIQx (2-amino-3,8-dimethylimidazo[4,5-f]quinoxaline), norharman (9H-pyrido[3,4-b]indole) and harman (1-methyl-9H-pyrido[3,4-b]indole), in ready-to-eat (RTE) cooked ham processed by electron-beam (accelerated electrons) irradiation to eliminate pathogenic microorganisms and to extend its shelf-life. The HAs selected have frequently been detected and quantified in a wide range of food and could be potential markers to indicate the presence of these toxic compounds. The method is based on the separation in an Inertsil C(8) capillary column (150 mm x 0.3-mm internal diameter, 3 microm) by gradient elution mode using a mixture of acetonitrile and 30 mM ammonium acetate pH 4.5 buffer as the mobile phase. Detection was at 250 and 265 nm and, to improve sensitivity, large injection volumes (20 microL) and on-column focusing techniques based on the injection of HA samples in low organic solvent strength solutions were employed. A simple and short solid-phase extraction and purification procedure was also optimized for sample preparation. Nonirradiated and irradiated RTE cooked ham samples at doses between 1 and 8 kGy were analyzed. HAs were not detected in any of the samples analyzed; so both types of samples were spiked at concentration levels in the range 5-25 ng g(-1), which may be found in meat products. The quality parameters of the method developed in the food matrix were established, and detection limits around 0.3 ng g(-1) were obtained. Spiked recoveries between 70 and 79% (n = 3 for each spiked level) relative standard deviations between 1 and 5% were also obtained, showing the effectiveness of the proposed method.

Sequencing batch reactor (SBR) as optimal method for production of granular activated sludge (GAS)--fluid dynamic investigations.

Fluid dynamic investigations of multiphase flow (fluid, air, granules) in a sequencing batch reactor (SBR) are presented. SBR can be considered as an attractive technology for cultivation of granular activated sludge (GAS). Granulation is a complicated process and its mechanism is not fully understood yet. Many factors influence the formation and structure of aerobic granular sludge in a bioreactor. Extracellular polymer substances (EPS) and superficial gas velocity (SGV) play a crucial role for granules formation. Additionally, it is supposed that EPS production is stimulated by mechanical forces. It is also assumed that hydrodynamic effects have a major influence on the formation, shape and size of GAS in SBR under aerobic condition. However, the influence of stress on granulation is poorly investigated. Thus, in the present paper, fluid dynamic investigations of multiphase flow in a SBR, particularly effect of normal and shear strain, are reported. In order to analyse multiphase flow in the SBR, optical in-situ techniques with particle image velocimetry (PIV) and particle tracking velocimetry (PTV) are implemented. Obtained results show a characteristic flow pattern in a SBR. It is pointed out that additional effects like particle-wall collisions, inter particle collisions, erosion can also affect significantly granules formation.

Reassessment of the methyl derivatization reaction of carbamates with sodium hydride/dimethyl sulfoxide/methyl iodide for their determination by gas chromatography.

A deep revision of the carbamate methyl derivatization reaction with sodium hydride/dimethyl sulfoxide/methyl iodide was carried out. Representative carbamates, R(1)-NH-COO-R(2), mainly N-methyl and N-aryl ones, have been studied in order to clarify which carbamates undergo this reaction. Two possible reaction routes are proposed; the route depends on the carbamate substituent (-OR(2) group) more than on the methyl or aryl groups joined to the NH moiety as literature indicates. The classification of carbamates in N-methyl and N-aryl is not suitable to predict the methylation pathway. A laboratory-made closed reactor allows handling the reagents involved, minimizing hazards and simplifying the procedure for rapid analysis.

Indirect chiral HPLC determination and fluorimetric detection of D-amino acids in milk and oyster samples.

The indirect chiral method, based on the o-phthaldialdehyde reaction using the chiral N-acetyl-L-cysteine reagent, has been optimized to determine D-amino acids in milk and oyster samples. Both the derivatization reaction and the HPLC separation have been improved, and simple sample treatments were proposed. The milk sample preparation involved centrifugation and filtration through polytetrafluoroethylene filters for determination of free D-AA. Two methods, nonenzymatic and enzymatic, were applied to determination of free and total D-AA, respectively, in oyster samples. The D-AA contents were in the range of 0.14 to 4.32 mg/L for milk samples and 0.80 to 15.9 mg/g for oyster samples, with relative standard deviations lower than 10% (n = 4), except for D-Tyr. In general, mean recoveries were greater than 90% with relative standard deviations lower than 9% (n = 4) at concentration levels from 0.055 to 0.426 mg/L for milk samples and 0.348 to 1.10 mg/ g for oyster samples.

Pustular generalized perforating granuloma annulare.

We report a 84-year-old man with a 13-year history of recurrent generalized asymptomatic pustular lesions. Histology revealed areas of necrobiosis surrounded by palisading granulomas and transepidermal and follicular elimination of the necrobiotic material. A dense infiltrate of neutrophils was also found. Although 26% of patients with generalized perforating granuloma annulare have some yellow pustule-like papules, these correspond histologically to the yellow viscous necrobiotic material extruding through the epidermis and not to a real neutrophilic infiltrate. This is the first case report of perforating granuloma annulare with recurrent generalized pustular lesions with a dense infiltrate of neutrophils.

Identification of pheromones in mouse urine by head-space solid phase microextraction followed by gas chromatography-mass spectrometry.

Given the key role of pheromones in animal communication and behaviour, there is need to identify the different classes of these molecules under varying physiological conditions. However, the highly volatile nature of pheromones and the fact that they occur at very low concentrations in urine makes this task all the more difficult. Herein, we present a method of detecting and identifying the five main pheromones known: 2-sec-butyl-4,5-dihydrothiazole, geraniol, indole, trans-beta farnesene and trans-alpha farnesene in individual urine microsamples taken from male mice. Urine volumes as small as 20 microl were subjected to solid phase microextraction (SPME) followed by gas chromatography-mass spectrometry (GC-MS). This selective analytical method permits the rapid detection of these pheromones free from cross-contaminants as a clearly distinguishable spectral signals. Highest recovery rates of natural pheromones were achieved by extraction on a carboxen/polydimethylsiloxane (CAR/PDMS) fibre of 85 microm film thickness. This selective, sensitive and accurate method will help address the question of possible links between certain pheromone classes, and social and reproductive behaviour in mice.