Alpinone: A positive regulator molecule of immune antiviral response in Atlantic salmon kidney cells

Alpinone is a flavonoid obtained from the resinous exudate of Heliotropium huascoense. This flavonoid shows antiviral activity against the infectious salmon anemia virus (ISAV), which causes severe disease in farmed Atlantic salmon. Here, we aim to elucidate mechanisms underlying the antiviral effects of the flavonoid. In this regard, we evaluated whether Alpinone can act upregulating the pattern-recognition receptor genes, i.e., the RIG-I-like, TLR3, and TLR9 genes, and the genes of the downstream signaling pathways. Transcriptional expression of the genes was analyzed using real-time PCR after 8, 24, and 48 h treatment of salmon kidney adherent cells with 15 μg/mL of Alpinone. First, we showed that Alpinone induced IFNa expression in the kidney adherent cells, indicating that this type of salmon cells is in part responsible for the effects previously reported in vivo. Upregulation of the IFN-induced myxovirus resistance (Mx) gene was also observed in the head kidney cells in response to the treatment. Overexpression reached a maximum level at 24 h post-treatment. Interestingly, Alpinone also induced upregulation of the cytosolic receptors of ssRNA, named Retinoic acid-inducible gene I (RIG-I) and Melanoma Differentiation-Associated protein 5 (MDA5), but there were no effects on the transcriptional expression of the TLR3 and TLR9 endosomal receptors. In addition, Alpinone upregulated the expression of genes encoding the main components of the RIG-I/MDA5 signaling pathways, such as the mitochondrial antiviral-signaling protein (MAVS), TNF Receptor Associated Factor 3 (TRAF3), TANK-binding kinase 1 (TBK1), I-kappaB kinase ε (IKKε), the transcription factors IRF-3, and IRF7. The increased expression of all these genes is consistent with the upregulation of IFNa and Mx mRNAs. Because BX795 completely prevents Alpinone-dependent upregulation of IFNa and IRF3, the flavonoid targets seem to be upstream of the kinases TBK1 and IKKε. Altogether, this study contributes to elucidating the mechanisms involved in Alpinone antiviral activity in fish. Alpinone can be used to counteract virus mechanisms of evasion where the onset of interferon-mediated response is prevented or delayed.

Correction to: Validation of the Spanish Version of Fear of COVID-19 Scale: its Association with Acute Stress and Coping

[This corrects the article DOI: 10.1007/s11469-021-00615-x.].

Validation of the Spanish Version of Fear of COVID-19 Scale: its Association with Acute Stress and Coping its Association with Acute Stress and Coping

The COVID-19 is a “unique” stressor, which can produce physical and psychological trauma. Coping styles can buffer this psychological impact. Consequently, this paper aims to psychometrically adapt the Fear of COVID-19 scale (FCV-19S) to Spanish and examines the relationships between FCV-19S, stress response, and coping strategies. The sample comprised a convenience sample of 1146 participants (12–83 years), 880 from Spain (76.8%), and 266 from Dominican Republic (23.2%). Overall, the findings support a one-factor structure for FCV-19S, consisting of 7-items, and was invariant across age, sex, occupational status, and cross-national. Therefore, indicating evidences of construct validity. Evidences of reliability were also observed (Cronbach’s α = .86, McDonald’s ω = .86, Guttmann’s λ6 = .86, greatest lower bound = .91, composite reliability = .85, and average variance extracted = .44). Moreover, as regards criterion-related validity, the mediation analysis indicated that the relationship between FCV-19S and acute stress was positive and high, with maladaptive coping styles mediating the relationship, and with a stronger mediation for men. The findings give evidences of the reliability and validity of the Spanish version of FCV-19S among Spanish-speaker participants, which provides the chance of cross-cultural studies.

The Atlantic salmon interleukin 4/13 receptor family: Structure, tissue distribution and modulation of gene expression

Interleukin (IL)-4 and IL-13 play a central role in T helper 2 immune response in mammals. The cell signalling is mediated by the type I heterodimeric receptor containing the IL-4Rα and γC chains, and the type II receptors formed by IL-4Rα and IL-13Rα1. In salmonid species, three paralogues of the IL-4 and IL-13 cytokines have been reported, il-4/13a, il-4/13b1 and il-4/13b2. In regard to receptors, two paralogues of each IL-4/13 receptor chains have been identified in rainbow trout while five genes named γc1, il-4rα, il-13rα1a, il-13rα1b, and il-13rα2 have identified in Atlantic salmon. Since Atlantic salmon is an important farmed fish species, the aim of this work was to get new insights into distribution, structure and expression regulation of the IL-4/13 receptors in salmon. By using qRT-PCR, it was shown that all γc1, il-4rα, il-13rα1a, il-13rα1b, and il-13rα2 receptor chains were expressed in lymphoid and non-lymphoid tissues of healthy salmon, nonetheless γC expression was higher in lymphoid than non-lymphoid tissues. The in silico structural analysis and homology modelling of the predicted receptor proteins showed that domains and most motifs present in the superior vertebrate chains are conserved in salmon suggesting a conserved role for these receptor chains. Only IL-13Rα1B is a receptor chain with a unique structure that seem not to be present in higher vertebrates but in fish species. In order to determine the regulatory role of IL-4/13 on the expression of receptor chains, Atlantic salmon il-4/13A gene was synthetized and cloned in pET15b. The recombinant IL-4/13A was produced in E. coli and the activity of the purified cytokine was confirmed in vitro. The regulatory role of IL-4/13A on the expression of their potential receptors was tested in salmon receiving the recombinant cytokine and effects were compared with those of the control group. The results showed that IL-4/13A induced the expression of its own gene and GATA-3, in the head kidney of fish but not in the spleen, while IL-10 increased in both lymphoid organs indicating a regulatory role of this cytokine on the induction of Th2 responses in salmon. IFN-γ and MHC class II were also later induced in head kidney. In regard to the expression of the receptor chains, IL-4/13A upregulated the expression of γC, IL-13Rα1A and IL-13Rα2A in the spleen but not in the head kidney of salmon, indicating a role on the modulation of cell signalling for the Th2 response. Furthermore, Piscirickettsia salmonis infection of Atlantic salmon occurred with an increase of γC and IL-13Rα1A suggesting a potential role of the IL-4/13 system in bacterial immunity or pathogenesis. This study contributes to a better understanding of the IL-4/13A system in salmon, which as a key axis for Th2 response may be involved not only in pathogen elimination but also in adaptive immune repair that seems critical tolerance to infectious diseases.

Determining personalized treatment by gene expression profiling in metastatic breast carcinoma patients: a pilot study

PURPOSE

The present study evaluates the massive study of gene expression in metastatic breast carcinoma (MBC) patients using microarray gene expression profiling (MAGE) complemented with conventional sequencing, immunohistochemistry (IHC) and fluorescent "in situ" hybridization (FISH), seeking to optimize the treatment in a subset of heavily pretreated patients and with limited life expectancy.

PATIENTS, MATERIAL AND METHODS

MBC patients in hormone therapy progression with survival expectancy of at least 3 months (m) have been included. The MAGE contains gene probes representing genes known to potentially interact with available drugs as cited in the literature.

RESULTS

Thirty-nine procedures were performed from October 2010 to April 2016. Within the 30 evaluable procedures, considering all hormonal manipulations as a single line, the patients had received a median of 4 treatment lines prior to MAGE (range 1-7). Progression was observed in 6 cases, stable disease (SD) in 7 cases and partial response (PR) in 16 cases, which implies a clinical benefit rate (SD + PR) of 76%. Actuarial median progression-free survival (PFS) was 6 m (95% CI 2.5-9.5) in patients with clinical benefit. The median overall survival (OS) for the entire series was 11 m (95% CI 2.2-19.8).

CONCLUSION

Data presented here indicate that the use of MAGE provides relevant information to establish personalized treatment in frail patients with limited life expectancy in which therapeutic futility is a particularly difficult burden to assume.

Alpinone exhibited immunomodulatory and antiviral activities in Atlantic salmon

In this study, we seek to identify flavonoids able to regulate the gene expression of a group of cytokines important for the control of infections in Atlantic salmon (Salmo salar). Particularly, we studied the potential immunomodulatory effects of two flavonoids, Alpinone and Pinocembrine, which were isolated and purified from resinous exudates of Heliotropium huascoense and Heliotropium sinuatum, respectively. The transcript levels of TNF-α and IL-1 (inflammatory cytokines), IFN-γ and IL-12 (T helper 1 type cytokines), IL4/13A (Th2-type cytokine), IL-17 (Th17 type cytokine) TGF-β1 (regulatory cytokine) and IFN-α (antiviral cytokine) were quantified by qRT-PCR in kidneys of flavonoid-treated and control fish. We demonstrated that the administration of a single intramuscular dose of purified Alpinone increased the transcriptional expression of five cytokines, named TNF-α, IL-1, IFN-α, IFN-γ and TGF-β1 in treated fish compared to untreated fish. Conversely, administration of purified Pinocembrine reduced the transcriptional expression of TNF-α, IL-1 and IL-12 in the kidney of treated fish. No other changes were observed. Interestingly, Alpinone also induced in vitro antiviral effects against Infectious Salmon Anaemia virus. Results showed that Alpinone but not Pinocembrine induces the expression of cytokines, which in vertebrates are essential to control viral infections while Pinocembrine reduces pro-inflammatory cytokines. Altogether results suggest that Alpinone is a good candidate to be further tested as immunostimulant and antiviral drug.

β-1,3/1,6-Glucan-supplemented diets antagonize immune inhibitory effects of hypoxia and enhance the immune response to a model vaccine

The diets of farmed salmon are usually supplemented with immunostimulants to improve health status. Because β-glucan is one of the most common immunostimulants used in diets, here we examined the effect of two β-1,3/1,6-glucan-supplemented diets on the expression of immune response genes of Atlantic salmon. The relative abundances of IFN-α1, Mx, IFN-γ, IL-12, TGF-β1, IL-10, and CD4 transcripts were evaluated in head kidney by qRT-PCR. We assessed the effects of the diets under normoxia and acute hypoxia, as salmon are especially sensitive to changes in the concentration of dissolved oxygen, which can also affect immunity. These effects were also tested on vaccinated fish, as we expected that β-1,3/1,6-glucan-supplemented diets would enhance the adaptive immune response to the vaccine. We found that administration of the Bg diet (containing β-1,3/1,6-glucan) under normoxia had no effects on the expression of the analyzed genes in the kidney of the diet-fed fish, but under hypoxia/re-oxygenation (90 min of acute hypoxia), the βg diet affected the expression of the antiviral genes, IFN-α1 and Mx, preventing their decrease caused by hypoxia. The Bax diet, which in addition to β-1,3/1,6-glucan, contained astaxanthin, increased IL-12 and IFN-γ in kidneys. With fish exposed to hypoxia/reoxygenation, the diet prevented the decrease of IFN-α1 and Mx levels observed after hypoxia. When fish were vaccinated, only the levels of IL-12 and CD4 transcripts increased, but interestingly if fish were also fed the Bax diet, the vaccination induced a significant increase in all the analyzed transcripts. Finally, when vaccinated fish were exposed to hypoxia, the effect of the Bax diet was greatly reduced for all genes tested and moreover, inducible effects completely disappeared for IL-12, IFN-α, and Mx. Altogether, these results showed that the tested β-1,3/1,6-glucan diets increased the levels of transcripts of key genes involved in innate and adaptive immune response of salmon, potentiating the response to a model vaccine and also antagonizing the effects of hypoxia.

Isolation and Characterization of Salmonid CD4+ T Cells

This study reports the isolation and functional characterization of rainbow trout (Oncorhynchus mykiss) CD4-1(+) T cells and the establishment of an IL-15-dependent CD4-1(+) T cell line. By using Abs specific for CD4-1 and CD3ε it was possible to isolate the double-positive T cells in spleen and head kidney. The morphology and the presence of transcripts for T cell markers in the sorted CD4-1(+)CD3ε(+) cells were studied next. Cells were found to express TCRα, TCRβ, CD152 (CTLA-4), CD154 (CD40L), T-bet, GATA-3, and STAT-1. The sorted CD4-1(+) T cells also had a distinctive functional attribute of mammalian T lymphocytes, namely they could undergo Ag-specific proliferation, using OVA as a model Ag. The OVA-stimulated cells showed increased expression of several cytokines, including IFN-γ1, IL-4/13A, IL-15, IL-17D, IL-10, and TGF-β1, perhaps indicating that T cell proliferation led to differentiation into distinct effector phenotypes. Using IL-15 as a growth factor, we have selected a lymphoid cell line derived from rainbow trout head kidney cells. The morphology, cell surface expression of CD4-1, and the presence of transcripts of T cell cytokines and transcription factors indicated that this is a CD4-1(+) T cell line. To our knowledge, this is the first demonstration of the presence of CD4-1(+)CD3ε(+) T cells in salmonids. As in mammals, CD4-1(+) T cells may be the master regulators of immune responses in fish, and therefore these findings and the new model T cell line developed will contribute to a greater understanding of T cell function and immune responses in teleost fish.

Key cytokines of adaptive immunity are differentially induced in rainbow trout kidney by a group of structurally related geranyl aromatic derivatives

Filifolinone is a semi-synthetic terpenoid derivative obtained from Heliotropium filifolium that increases the expression level of pro-inflammatory and anti-inflammatory cytokines in kidney cells of salmon. Because cytokines are produced in response to a foreign organism and by distinct other signals modulating immune responses, we further studied the potential immunomodulatory effects of a group of structural related terpenoid derivatives from H. filifolium on salmonids to determine the relationship between the chemical structure of the derivatives and their ability to modify cytokine expression and the lymphoid content. The resin and four 3H-spiro 1-benzofuran-2,1'-cyclohexane derivatives were tested in vivo in rainbow trout (Oncorhynchus mykiss) by quantifying the transcript levels of antiviral and T helper-type cytokines and T and B cells in the kidney. Three of the four terpenoids differ only in the C-7'substituent of the cyclohexane and the presence of the ketone group at this position in Filifolinone appeared responsible of an important up-regulation of IFN-α1, IFN-γ, IL-4/13A and IL-17D in the kidney of the treated trout. In addition, the absence of a methoxy group in carbon 7 of the benzene ring, found in all compounds but not in Folifolinoic acid, produced a significant reduction of IFN-γ, IL-12 and IL-4/13A transcripts. B cells were not affected by the compound treatment but Filifolinoic acid and the resin induced a significant reduction of T cells. Altogether, results showed that immunomodulating responses observed in the trout by effect of 3H-spiro 1-benzofuran-2,1'-cyclohexane derivatives is related to the presence of the ketone group in the carbon 7' and the methoxy group in carbon 7 of the benzene ring, being Filifolinone the most active immunostimulatory compound identified.

Neuroendocrine mechanisms for immune system regulation during stress in fish

In the last years, the aquaculture crops have experienced an explosive and intensive growth, because of the high demand for protein. This growth has increased fish susceptibility to diseases and subsequent death. The constant biotic and abiotic changes experienced by fish species in culture are challenges that induce physiological, endocrine and immunological responses. These changes mitigate stress effects at the cellular level to maintain homeostasis. The effects of stress on the immune system have been studied for many years. While acute stress can have beneficial effects, chronic stress inhibits the immune response in mammals and teleost fish. In response to stress, a signaling cascade is triggered by the activation of neural circuits in the central nervous system because the hypothalamus is the central modulator of stress. This leads to the production of catecholamines, corticosteroid-releasing hormone, adrenocorticotropic hormone and glucocorticoids, which are the essential neuroendocrine mediators for this activation. Because stress situations are energetically demanding, the neuroendocrine signals are involved in metabolic support and will suppress the "less important" immune function. Understanding the cellular mechanisms of the neuroendocrine regulation of immunity in fish will allow the development of new pharmaceutical strategies and therapeutics for the prevention and treatment of diseases triggered by stress at all stages of fish cultures for commercial production.

[Stability study of oxaliplatin and doxorubicin for intraperitoneal administration with hyperthermia]

OBJECTIVE

To evaluate the in vitro physicochemical stability of oxaliplatin and doxorubicin when the in vivo hyperthermic intraperitoneal conditions are reproduced.

METHODS

Three solutions were prepared, A (oxaliplatin 200 mg/L), B(doxorubicin 15 mg/L) and C (oxaliplatin 200 mg/L with doxorubicin 15mg/L) in glucose 5%. The three solutions were subjected to the maximum temperature reached in vivo (49° C) for two hours. Physical stability was focused on visual control of particles or precipitates in solutions, discharge of gases, odor and color. Samples were taken every 15 minutes and the chemical stability was evaluated by determining the concentration of oxaliplatin and doxorubicin remaining in the samples. Oxaliplatin concentrations were determined by atomic absorption graphite chamber while doxorubicin was determined by high performance liquid chromatography.The chemical stability criteria selected was the one described by the American Pharmacopoeia, which sets a permissible variation range between the 90-110% of the initial concentration.

RESULTS

During the assay there was no appearance of particles, precipitates in the samples, discharge of gases, nor colour changes in the solutions. The samples showed a remaining concentration of oxaliplatin and doxorubicin within the 90-110% limit. The stability of the samples that follow to two cycles of freeze-thaw after hyperthermia was also found within the specified limits.

CONCLUSION

A, B and c solutions in 5% glucose, are physically and chemically stable at 49° C for two hours. Under these conditions, these solutions could be used with guarantees of stability in patients with peritoneal carcinomatosis subsidiary of intraperitoneal hyperthermic chemotherapy based in these antineoplastic agents.

Immunomodulatory effects of the aromatic geranyl derivative filifolinone tested by the induction of cytokine expression

Fish farming crops are constantly exposed to infectious diseases due to intensive production conditions under which microorganisms develop and spread easily, resulting in severe economic losses. The massive use of antibiotics to control these diseases has lead to the accumulation of residues and the development of drug resistance. Consequently, it is urgent to develop new pharmacological tools to stimulate protective immune responses in salmonids to combat infectious diseases. We evaluated the immunostimulant activity of terpenoid derivatives isolated from species of the Heliotropium genus, which had previously shown antiviral activity in salmon. The immunomodulatory effects of the 3 H-spiro [1-benzofuran-2,1'-ciclohexane] derivative called filifolinone, were studied in vitro using the SHK-1 cell line derived from leucocytes of salmon head kidney and in vivo in Atlantic salmon. For the evaluation, we studied the effect of this compound in the expression of various cytokines. The results showed that Filifolinone increases the levels of expression of pro-inflammatory and anti-inflammatory cytokines. This suggests that Filifolinone is a potential alternative immunomodulator for veterinary purposes.

Epidermal growth factor receptor (EGFR) mutations in a series of non-small-cell lung cancer (NSCLC) patients and response rate to EGFR-specific tyrosine kinase inhibitors (TKIs)

INTRODUCTION Epidermal growth factor receptor (EGFR) mutation related to tyrosine kinase inhibitors' (TKIs) responsiveness in non-small cell lung cancer (NSCLC) has become an important issue for therapeutic decision-making in NSCLC patients. MATERIAL AND METHODS Sixty-nine Caucasian NSCLC patients were screened for mutations in the tyrosine kinase (TK) domain of EGFR by direct sequencing from December 2005 to September 2010. RESULTS Activating mutations in the EGFR TK domain were found in 8 of 69 (11.6%) (7 deletions in exon 19 and one L858R mutation in exon 21). Seven of those mutations were found in adenocarcinoma and one mutation in bronchiolo-alveolar carcinoma; five of them in females (one smoker) and three of them in males (one smoker). All patients carrying activating mutations in the TK domain of EGFR were treated with TKIs. Ten patients not carrying an activating mutation in EGFR, who progressed after chemotherapy, were also treated with compassionate use of EGFR-specific TKIs (gefitinib or erlotinib). An objective response (partial response) was observed in all patients carrying an activating mutation in EGFR that received TKIs. Median overall survival for these patients has not been reached, however mean survival has been estimated at 39.5 months (95% CI, 22-57). CONCLUSIONS As previously reported, EGFR TK mutational analysis was a predictive test for response to targeted therapy with EGFR TKIs. The early identification of these patients consistently attains disease response and clearly improves outcomes.

[Population pharmacokinetics of gemcitabine applied to personalize the dosage used in cancer patients]

OBJECTIVE

To develop and internally validate a population pharmacokinetic model for gemcitabine and its metabolite 2',2'-difluorodeoxyuridine (dFdU); and to evaluate its predictive perfomance for personalizing the dosage used in cancer patients.

METHODS

Gemcitabine and dFdU plasma concentrations were determined in 18 cancer patients. A 2-compartment pharmacokinetic model was implemented in the NONMEN VI program to determine the appropriate pharmacokinetic parameters. The power to identify the parameters was assessed by parametric bootstrap, and the internal model validation was performed using nonparametric bootstrap and visual and numerical predictive check methods. The final predictive performance of the model was assessed for accuracy and precision during the first (a priori) and second (a posteriori) chemotherapy cycles.

RESULTS

The mean and interpatient variability of gemcitabine and dFdU clearance was 2.70 L/min (31.0%) and 0.0515 L/min (35.8%), respectively. The estimated distribution volume at steady state was 30 L for gemcitabine and 238 L for dFdU. Internal validation confirmed that the population pharmacokinetic model was appropriate for describing the plasma concentrations of gemcitabine and dFdU over time, as well as its variability in the study population. The accuracy and precision of a posteriori gemcitabine plasma concentrations improved by 67% and 46%, respectively, compared to the a priori prediction.

CONCLUSION

The population pharmacokinetic model adequately characterised the gemcitabine and dFdU plasma concentrations in the study population over time, and can be used to accurately and precisely optimise gemcitabine dosing regimens in cancer patients.

[Populational pharmacokinetics of doxorubicin applied to personalised its dosing in cancer patients]

OBJECTIVE

To develop and internally validate a population pharmacokinetic model for doxorubicin and to evaluate its predictive performance for dose individualization in cancer patients.

METHODS

Doxorubicin plasma concentrations were determined in thirty-three cancer patients treated with intravenous doxorubicin. A three-compartment pharmacokinetic model was implemented in the NONMEN VI programme to determine the doxorubicin pharmacokinetic parameters. The identifiability of the parameters was assessed by parametric bootstrap and model validation was performed using nonparametric bootstrap, visual predictive check, and numerical predictive check. The final model's predictive performance was evaluated in terms of accuracy and precision of plasma concentration predictions during the first and second cycles of chemotherapy.

RESULTS

Doxorubicin clearance was 58.8 L/h, with interpatient variability of 29.2% and intrapatient variability of 18.9%. The estimated volume of distribution at steady state was 2294 L, with inter-and intrapatient variability of 7.3% and 26.1%, respectively. Internal validation confirmed that the population pharmacokinetic model is appropriate to describe the time course of the doxorubicin plasma concentrations and its variability in this population. The accuracy and precision of an a posteriori prediction of doxorubicin plasma concentrations improved by 63% and 41% compared to the a priori prediction.

CONCLUSION

The Bayesian population pharmacokinetic model characterised the time course of doxorubicine plasma concentrations and can be accurately and precisely used to optimise doxorubicine dosing regimens in cancer patients.

Conductivity anisotropy in the antiferromagnetic state of iron pnictides

Recent experiments on iron pnictides have uncovered a large in-plane resistivity anisotropy with a surprising result: The system conducts better in the antiferromagnetic x direction than in the ferromagnetic y direction. We address this problem by calculating the ratio of the Drude weight along the x and y directions, D(x)/D(y), for the mean-field Q=(π,0) magnetic phase diagram of a five-band model for the undoped pnictides. We find that D(x)/D(y) ranges between 0.2<D(x)/D(y)<1.7 for different interaction parameters. Large values of the orbital ordering favor an anisotropy opposite to the one found experimentally. On the other hand, D(x)/D(y) is strongly dependent on the topology and morphology of the reconstructed Fermi surface. Our results point against orbital ordering as the origin of the observed conductivity anisotropy, which may be ascribed to the anisotropy of the Fermi velocity.

Low magnetization and anisotropy in the antiferromagnetic state of undoped iron pnictides

We examine the magnetic phase diagram of iron pnictides using a five-band model. For the intermediate values of the interaction expected to hold in the iron pnictides, we find a metallic low moment state characterized by antiparallel orbital magnetic moments. The anisotropy of the interorbital hopping amplitudes is the key to understanding this low moment state. This state accounts for the small magnetization measured in undoped iron pnictides and leads to the strong exchange anisotropy found in neutron experiments. Orbital ordering is concomitant with magnetism and produces the large zx orbital weight seen at Γ in photoemission experiments.

UGT1A1,A7 and A9 genotyping and pharmacokinetics of irinotecan-containing chemotherapy in patients with advanced cancer

e14563

Background: To the best of our knowledge only one previous report in asian lung cancer patients (pts) assesed UGT1A1, A7 and A9 genotypes along with irinotecan pharmacokinetics (Han et al. JCO 2006; 24: 2237–44). We set out to evaluate UGT1A1, A7 and A9 genotypes in caucasian cancer patients and their relationship with both irinotecan toxicity and irinotecan pharmacokinetics. Methods: UGT1A1, A7 and A9 genotypes were obtained from blood genomic DNA by direct sequencing. The area under the time-concentration curve (AUC) of SN-38 and SN-38G were calculated. The ratio between these AUCs (AUC SN-38G /AUC SN-38) was also calculated. Associations between pharmacokinetics parameters and the UGT1A genotypes were assessed by univariate analysis. Toxicity was collected using standard NCI grading criteria. Statistical correlation between presence of grade III and IV toxicity and UGT1A1,A7 and A9 genotypes was done by Pearson's Chi square. At least 80 patients (with both genotype and pharmacokinetics) are needed to achieve enough statistical power. Results: At the time of writing this abstract, complete genotyping and toxicity data from 59 patients were available. Sex (females 17, males 42). Median age 60 (range 25–88). Pathology (no. pts): lung (26), colon (17), others (16). 21 pts. (35.59%) had received previous chemotherapy. All but 5 pts received doses of irinotecan between 120 and 150 mg/m2. Median no. of cycles 6 (range 1–15). The frequencies of the different UGT1A1, A7 and A9 genotypes are similar to those previously reported. At least one episode of grade III or IV leukopenia was present in 19 pts. (32.2%), and grade III diarrea in 11 pts (18.6%). No statistically significant correlation was found between presence of leukopenia grades III and IV, and the genotypes UGT1A1,A7, and A9 (P=0.687, P=0.156 and P=0.476, respectively). Diarrea grade III was not statistically significantly associated with UGT1A1 (P=0.318), A7 (P=0.318) and A9 (P=0.158). 21 out of 59 pts. had pharmacokinetics (PK) data available. In genotype-PK association analysis, UGT1A1,A7 and A9 were not statistically associated with AUC SN-38G / AUC SN-38 ratios (P=0.844, P=0.911, P=0.431, respectively). Conclusions: Patients are still being accrued to achieve the targeted size.

No significant financial relationships to disclose.

Characterization of the long-terminal repeat single-strand tail-binding site of Moloney-MuLV integrase by crosslinking

Processing of viral DNA by retroviral integrase leaves a dinucleotide single-strand overhang in the unprocessed strand. Previous studies have stressed the importance of the 5' single-stranded (ss) tail in the integration process. To characterize the ss-tail binding site on M-MuLV integrase, we carried out crosslinking studies utilizing a disintegration substrate that mimics the covalent intermediate formed during integration. This substrate carried reactive groups at the 5' ss tail. A bromoacetyl derivative with a side chain of 6 A was crosslinked to the mutant IN 106-404, which lacks the N-terminal domain, yielding a crosslinked complex of 50 kDa. Treatment of IN 106-404 with N-ethylmaleimide (NEM) prevented crosslinking, suggesting that Cys209 was involved in the reaction. The reactivity of Cys209 was confirmed by crosslinking of a more specific derivative carrying maleimide groups that spans 8A approximately. In contrast, WT IN was not reactive, suggesting that the N-terminal domain modifies the reactivity of the Cys209 or the positioning of the crosslinker side chain. A similar oligonucleotide-carrying iodouridine at the 5'ss tail reacted with both IN 106-404 and WT IN upon UV irradiation. This reaction was also prevented by NEM, suggesting that the ss-tail positions near a peptide region that includes Cys209.

Phenomenological description of the two energy scales in underdoped cuprate superconductors

Raman and angle-resolved photoemission spectroscopy experiments have demonstrated that in superconducting underdoped cuprates nodal and antinodal regions are characterized by two energy scales instead of the one expected in BCS theory. The nodal scale decreases with underdoping while the antinodal one increases. Contrary to the behavior expected for an increasing energy scale, the antinodal Raman intensity decreases with decreasing doping. Using the Yang-Rice-Zhang model, we show that these features are a consequence of the nonconventional nature of the superconducting state in which superconductivity and pseudogap correlations are both present and compete for the phase space.

Modelling intestinal absorption of salbutamol sulphate in rats

The objective was to develop a semiphysiological population pharmacokinetic model that describes the complex salbutamol sulphate absorption in rat small intestine. In situ techniques were used to characterize the salbutamol sulphate absorption at different concentrations (range: 0.15-18 mM). Salbutamol sulphate at concentration of 0.29 mM was administered in presence of verapamil (10 and 20 mM), grapefruit juice and sodium azide (NaN3) (0.3, 3 and 6 mM). Different pharmacokinetic models were fitted to the dataset using NONMEM. Parametric and non-parametric bootstrap analyses were employed as internal model evaluation techniques. The validated model suggested instantaneous equilibrium between salbutamol sulphate concentrations in lumen and enterocyte, and the salbutamol sulphate absorption was best described by a simultaneous passive diffusion (ka = 0.636 h(-1)) and active absorption (VMax = 0.726 mM/h, Km = 0.540 mM) processes from intestinal lumen to enterocyte, together with an active capacity-limited P-gp efflux (V'max = 0.678 mM/h, K'm = 0.357 mM) from enterocyte to intestinal lumen. The extent of salbutamol sulphate absorption in rat small intestine can be improved by NaN3, grapefruit juice and verapamil.

The influence of active secretion processes on intestinal absorption of salbutamol in the rat

Salbutamol was perfused in the small intestine of rat using a standard rat gut "in situ" preparation: (1) in inhibitor-free solution at seven different concentrations (0.15, 0.29, 1.20, 5.0, 9.0, 13.0 and 18.0mM); (2) at a 0.29mM concentration - thought to be close to the allometric dose in man - in the presence of a non-specific enzyme inhibitor, sodium azide (0.3, 3.0 and 6.0mM); and (3) at 0.29mM in the presence of a selective secretion inhibitor, verapamil (10.0 and 20.0mM). In free solution, the mixed-order rate constants, k'(a), of salbutamol increase as the solute concentration increases until an apparent asymptotic value is reached. This could be due to the saturation of enzymatic systems responsible for the secretion of the drug from the enterocyte to the luminal fluid, a process that could explain the poor absorption of salbutamol. In the presence of sodium azide, the k(a) values increased about 1.5-fold, whereas in the presence of verapamil they increased two- to three-fold. These results indicate that salbutamol can act as a substrate of an intestinal secretory transport, which probably includes--at least in part--the enzyme P-glycoprotein, since verapamil has been shown to inhibit this enzyme by dose-dependent competition. This leads to a secretion-limited peroral absorption of salbutamol, which contributes to the poor oral bioavailability of the drug. The possible options for improving salbutamol absorption are discussed.

[Juvenile myoclonic epilepsy. Life difficulties and response to treatment]

Juvenile myoclonic epilepsy (JME) may have different forms of clinical expression and produces different kinds of life difficulties. Both eventualities have not been sufficiently described in the literature. Treatment with valproic acid is useful but requires strict compliance of medical instructions. Thirty two patients with this disease, are presented in order to describe their presenting forms, associated life handicaps and the results of their treatment. The disease may first present as tonic-clonic, complex absence or complex partial seizures, followed months or years later, by typical myoclonic crisis or as JME to which other kinds of epileptic crisis may or not be added after some time. Twenty four (75%) patients had 38 life difficulties, these being, mainly, objects dropped from hand, burns and parental aggression. Eighteen (56.25%) patients had relapses during treatment. In 14 cases (77.77%) relapses were due to noncompliance, 8 (57.19%) patients couldn't afford the cost of valproic acid. Knowledge of the presenting forms of the disease may favor opportune diagnosis and treatment, which would prevent life difficulties. Relapses are mainly due to noncompliance and economic reasons.

[Juvenile myoclonic epilepsy: Janz' syndrome]

Thirty two patients with juvenile myoclonic epilepsy are described. The most relevant aspects of the disease are the following: it starts at nearly 12 years of age or before; it is frequently associated with generalized tonic-clonic seizures; myoclonic and tonic-clonic seizures occur at time of awaking or shortly after; no pathological findings occur at the central nervous system; a large number of relatives show generalized seizures and the interictal electroencephalogram is usually disturbed by generalized epileptic activity. Valproic acid, preferably alone, is probably the treatment of choice for these patients.

[Follow-up of infants with birth weight under 1,500 g]

A prospective study of 199 children with birth weight less than 1,500 g was done. 86 boys and 113 girls, 141 (71%) adequate for gestational age and 58 (29%) small for gestational age. At follow-up 43 (21.6%) infants were lost to control, 17 (7%) moved to other places and 7 (3.5%) died in the first year of life. In the first year of life, infants whose birthweights were adequate for gestational age had been hospitalized more frequently and the small for dates showed higher percentage of undernutrition. After the second year of life, it was possible to know the impairment. It was found 7.4% of cerebral palsy, 2.9% of hipoacusia and 2.2% of retinopathy of prematurity, these diagnosis were most frequent in children that were adequate for gestational age. We concluded that small for dates infants are at risk of undernutrition and that those adequate for gestational age are at risk of permanent sequelae.

The early development of the atrioventricular node and bundle of His in the embryonic chick heart. An electrophysiological and morphological study

The development of the atrioventricular node and bundle of His of embryonic chick hearts was studied by electrophysiological and morphological techniques. The dorsal wall of the AV canal and the interatrial septum were explored to determine if they contribute to the formation of the AV node and bundle of His. The resting membrane and action potentials of the interatrial septum cells were systematically analyzed and found to undergo progressive differentiation with development. The earliest identification of the AV node and upper bundle of His group of cells was achieved at 5 1/2–6 days of development by the electrical recording of their corresponding characteristic action potentials, from a circumscribed area located in the lowest and dorsal segment of the interatrial septum. The morphological and anatomical characterization of the cells was made following electrical recording and labelling with charcoal particles. The earlier AV node and bundle of His responses had similar characteristics to those of the adult heart. It is concluded that the AV node and upper bundle of His cells derive from the low interatrial septum. The possibility that AV canal cells contribute to this event was discarded. The functional relationship of the Av node and bundle of His with other cardiac tissues during the early development of the heart is discussed.

Electrophysiological and ultrastructural study of the atrioventricular canal during the development of the chick embryo

The development of the atrioventricular canal (A-V canal) of embryonic chick hearts (35 to 120 h) was studied by morphological and electrophysiological techniques. The earliest identification of the A-V canal action potentials was at 45 to 49 h of incubation coinciding with the atrium formation and the appearance of its corresponding distinctive action potential. At that time the first atrioventricular delay was recorded and its action potentials showed a low rate of rise, particularly at the initiation of the upstroke and a long duration. The conduction velocity was the lowest in the A-V canal. As the development proceeded from 45 to 120 h, the cardiac cells of the A-V canal showed scanty membrane to membrane contacts and large intercellular spaces filled with abundant extracellular matrix components, in striking contrast to the paucity of these components in the atrium and ventricle. The morphological and electrophysiological characteristics described for the A-V canal cells, could help to explain their slow conduction properties and the atrioventricular delay.