Brace yourselves: esports is coming

Background

Competitive gaming (or esports) is an emerging phenomenon with a field of over 454 million fans globally. Despite its tremendous popularity and commercial support, esports is not widely understood. It is also disregarded as a reputable or credible form of competition. The International Olympic Committee (IOC) contends that esports may be considered a sporting activity, but this is limited to the basis of its sedentary nature and poor governance.

Discussion

These authors present evidence to inform and clarify misconceptions surrounding esports among the broader scientific community. They also encourage researchers to engage in further work into the phenomenon of competitive gaming with regard to health and performance, resulting in a better understanding of esports and guiding its development as a credible, competitive entity.

HER3 targeting potentiates growth suppressive effects of the PI3K inhibitor BYL719 in pre-clinical models of head and neck squamous cell carcinoma

BYL719 is a PI3K inhibitor that has demonstrated efficacy in the treatment of head and neck squamous cell carcinoma. BYL719 exerts its therapeutic effect by suppressing AKT and other proliferative signaling mechanisms. Despite PI3K inhibition and AKT suppression, residual activity of protein S6, a core marker of proliferative activation, has been observed. HER3, either via dimerization or activation by its ligand neurgeulin (NRG), is known to activate PI3K. Thus, we hypothesized that co-targeting HER3 and PI3K would lead to greater suppression of the PI3K-AKT signaling pathway and greater tumor suppression than with BYL719 alone. We investigated biochemical expression and activation of the HER3-PI3K-AKT-S6 pathway in HNSCC cell lines and patient-derived xenografts (PDXs). Antitumor effects of HER3 and PI3K inhibitors alone and in combination were evaluated in cell culture and murine models. Treatment of HNSCC cell lines with BYL719 significantly reduced AKT activation and suppressed tumor growth. However, S6 was persistently activated despite suppression of AKT. Combination treatment with KTN3379, a monoclonal antibody targeted against HER3, and BYL719 led to enhanced suppression of in vitro and in vivo cancer growth and durable suppression of AKT and S6. Therefore, inhibition of HER3 with KTN3379 enhanced the effects of PI3K inhibition in pre-clinical HNSCC models. These data support co-targeting HER3 and PI3K for the treatment of HSNCC.

Cross-talk Signaling between HER3 and HPV16 E6 and E7 Mediates Resistance to PI3K Inhibitors in Head and Neck Cancer

Human papillomavirus (HPV) type 16 is implicated in approximately 75% of head and neck squamous cell carcinomas (HNSCC) that arise in the oropharynx, where viral expression of the E6 and E7 oncoproteins promote cellular transformation, tumor growth, and maintenance. An important oncogenic signaling pathway activated by E6 and E7 is the PI3K pathway, a key driver of carcinogenesis. The PI3K pathway is also activated by mutation or amplification of PIK3CA in over half of HPV(+) HNSCC. In this study, we investigated the efficacy of PI3K-targeted therapies in HPV(+) HNSCC preclinical models and report that HPV(+) cell line- and patient-derived xenografts are resistant to PI3K inhibitors due to feedback signaling emanating from E6 and E7. Receptor tyrosine kinase profiling indicated that PI3K inhibition led to elevated expression of the HER3 receptor, which in turn increased the abundance of E6 and E7 to promote PI3K inhibitor resistance. Targeting HER3 with siRNA or the mAb CDX-3379 reduced E6 and E7 abundance and enhanced the efficacy of PI3K-targeted therapies. Together, these findings suggest that cross-talk between HER3 and HPV oncoproteins promotes resistance to PI3K inhibitors and that cotargeting HER3 and PI3K may be an effective therapeutic strategy in HPV(+) tumors.Significance: These findings suggest a new therapeutic combination that may improve outcomes in HPV(+) head and neck cancer patients. Cancer Res; 78(9); 2383-95. ©2018 AACR.

Abstract PR04: HER3 crosstalk with HPV16-E6E7 is a feedback resistance mechanism to PI3K-targeted therapies in head and neck cancer

Human papillomavirus (HPV) 16 plays an etiologic role in a growing subset of head and neck squamous cell carcinoma (HNSCC), where viral expression of the E6 and E7 oncoproteins is necessary for tumor growth and maintenance. Although patients with HPV(+) tumors have a more favorable prognosis, there are currently no HPV-selective therapies. Accumulating evidence indicates that HPV oncoproteins can activate the Phosphoinositol-3-Kinase (PI3K) pathway, which contributes to transformation. Furthermore, PI3K is genomically activated by PIK3CA mutation or amplification in a disproportionately high number of HPV(+) tumors as compared to HPV(-) tumors. Based on this knowledge, we investigated the efficacy of PI3K-targeted therapies in preclinical models of HPV(+) HNSCC. Our results indicate that HPV(+) preclinical models were less sensitive to the PI3K inhibitors BYL719, BKM120, and BEZ235 as compared with HPV(-) models. Sensitivity of HPV(+) cell lines to PI3K inhibitors was increased upon knockdown of the E6 and E7 oncoproteins. Reciprocally, overexpression of E6 and E7 in HPV(-) cells rendered them resistant to PI3K-targeted therapies. Proteomic analyses indicated that treatment of HPV(+) cell lines and patient-derived xenografts (PDXs) with the PI3Kα inhibitor BYL719 induced expression of the receptor tyrosine kinase HER3, as well as E6 and E7. HER3 was found to regulate the abundance of E6 and E7 in the HPV(+) models. Targeting HER3 with siRNAs or the monoclonal antibody, KTN3379, blocked the increase in E6 and E7 protein levels following BYL719 treatment, and enhanced the efficacy of PI3K inhibitors in HPV(+) cell line and PDX models. Taken together, these results suggest that crosstalk between HER3 and HPV16-E6E7 can limit the efficacy of PI3K inhibitors, and that co-targeting HER3 and PI3K may be an effective therapeutic strategy in HPV(+) tumors.

This abstract is also being presented as Poster 67.

Citation Format: Toni M. Brand, Stefan Hartmann, Neil E. Bhola, Hua Li, Yan Zeng, Rachel O'Keefe, Max V. Ranall, Sourav Bandyopadhyay, Margaret Soucheray, Danielle L. Swaney, Nevan Krogan, Carolyn Kemp, Umamaheswar Duvvuri, Daniel E. Johnson, Michelle A. Ozbun, Julie E. Bauman, Jennifer R. Grandis. HER3 crosstalk with HPV16-E6E7 is a feedback resistance mechanism to PI3K-targeted therapies in head and neck cancer [abstract]. In: Proceedings of the AACR-AHNS Head and Neck Cancer Conference: Optimizing Survival and Quality of Life through Basic, Clinical, and Translational Research; April 23-25, 2017; San Diego, CA. Philadelphia (PA): AACR; Clin Cancer Res 2017;23(23_Suppl):Abstract nr PR04.

TMEM16A/ANO1 Inhibits Apoptosis Via Downregulation of Bim Expression

Purpose: TMEM16A is a calcium-activated chloride channel that is amplified in a variety of cancers, including 30% of head and neck squamous cell carcinomas (HNSCCs), raising the possibility of an anti-apoptotic role in malignant cells. This study investigated this using a multimodal, translational investigation.Experimental Design: Combination of (i) in vitro HNSCC cell culture experiments assessing cell viability, apoptotic activation, and protein expression (ii) in vivo studies assessing similar outcomes, and (iii) molecular and staining analysis of human HNSCC samples.Results: TMEM16A expression was found to correlate with greater tumor size, increased Erk 1/2 activity, less Bim expression, and less apoptotic activity overall in human HNSCC. These findings were corroborated in subsequent in vitro and in vivo studies and expanded to include a cisplatin-resistant phenotype with TMEM16A overexpression. A cohort of 41 patients with laryngeal cancer demonstrated that cases that recurred after chemoradiation failure were associated with a greater TMEM16A overexpression rate than HNSCC that did not recur.Conclusions: Ultimately, this study implicates TMEM16A as a contributor to tumor progression by limiting apoptosis and as a potential biomarker of more aggressive disease. Clin Cancer Res; 23(23); 7324-32. ©2017 AACR.

TMEM16A/ANO1 suppression improves response to antibody-mediated targeted therapy of EGFR and HER2/ERBB2

TMEM16A, a Ca²⁺ -activated Cl^- channel, contributes to tumor growth in breast cancer and head and neck squamous cell carcinoma (HNSCC). Here, we investigated whether TMEM16A influences the response to EGFR/HER family-targeting biological therapies. Inhibition of TMEM16A Cl^- channel activity in breast cancer cells with HER2 amplification induced a loss of viability. Cells resistant to trastuzumab, a monoclonal antibody targeting HER2, showed an increase in TMEM16A expression and heightened sensitivity to Cl^- channel inhibition. Treatment of HNSCC cells with cetuximab, a monoclonal antibody targeting EGFR, and simultaneous TMEM16A suppression led to a pronounced loss of viability. Biochemical analyses of cells subjected to TMEM16A inhibitors or expressing chloride-deficient forms of TMEM16A provide further evidence that TMEM16A channel function may play a role in regulating EGFR/HER2 signaling. These data demonstrate that TMEM16A regulates EGFR and HER2 in growth and survival pathways. Furthermore, in the absence of TMEM16A cotargeting, tumor cells may acquire resistance to EGFR/HER inhibitors. Finally, targeting TMEM16A improves response to biological therapies targeting EGFR/HER family members.

Abstract 2979: Dual targeting of HER3 and PIK3CA has potent anti-tumor effects in pre-clinical models of HNSCC

Background: The phosphoinositide 3-kinase (PI3K) pathway is a frequently mutated oncogenic pathway in head and neck squamous cell carcinoma (HNSCC). This pathway is often further activated by dysregulation of receptor tyrosine kinases, such as the epidermal growth factor receptor family. HER3 has a direct phosphorylation site with the regulatory subunit of PIK3CA, and is being investigated as a potential co-target to increase anti-tumor effects of PI3K inhibition. In this study, we use the human monoclonal antibody KTN3379, which blocks HER3 in the autoinhibited configuration and thus inhibits ligand-independent and ligand, neuregulin β-1,-dependent HER3 activation, and an inhibitor of PIK3CA (BYL719) to determine if HER3 and PIK3CA can be inhibited in a synergistic fashion. KTN3379 and BYL719 are clinical stage compounds and are being evaluated in HNSCC clinical trials.

Methods and Results: Treatment with neuregulin β-1 significantly increased phosphorylation of HER3, AKT, and S6 across HNSCC cell lines, regardless of baseline level of HER3 expression. HER3 inhibition (KTN3379) consistently abrogated these effects and decreased baseline phosphorylation of HER3. Combined blockade of HER3 (KTN3379) and PI3K (BYL719) inhibited the growth of HNSCC cell lines in a synergistic fashion (CI range 0.1-0.5), in both cell proliferation and colony formation assays. This synergy appeared to be less pronounced in HPV-associated cancer cell lines. Combined treatment decreased tumor growth in xenograft models of HNSCC. Furthermore, treatment of some HNSCC cell lines with BYL719 led to upregulation of the HER3 protein in HNSCC cell lines by Western blotting analysis, suggesting a possible role of HER3 in PI3K pathway inhibitor resistance.

Conclusion: HER3 interacts with PI3KCA, and the PI3K pathway in multiple HNSCC cell lines, and combined blockade has synergistic effects in pre-clinical HNSCC models. These findings suggest that HER3 and PI3K dual inhibition may be more effective in tumors that are resistant to mono-therapy with either HER3 or PI3K inhibition alone.

Citation Format: Nayel Khan, Kara S. Davis, Neal Godse, Carolyn Kemp, Sucheta Kulkarni, Diego Alvarado, Theresa LaVallee, Jennifer R. Grandis, Umamaheswar Duvvuri. Dual targeting of HER3 and PIK3CA has potent anti-tumor effects in pre-clinical models of HNSCC. [abstract]. In: Proceedings of the 107th Annual Meeting of the American Association for Cancer Research; 2016 Apr 16-20; New Orleans, LA. Philadelphia (PA): AACR; Cancer Res 2016;76(14 Suppl):Abstract nr 2979.

Sample introduction interface for on-chip nucleic acid-based analysis of Helicobacter pylori from stool samples

Despite recent advances in microfluidic-based integrated diagnostic systems, the sample introduction interface, especially with regards to large volume samples, has often been neglected. We present a sample introduction interface that allows direct on-chip processing of crude stool samples for the detection of Helicobacter pylori (H. pylori). The principle of IFAST (immiscible filtration assisted by surface tension) was adapted to include a large volume sample chamber with a septum-based interface for stool sample introduction. Solid chaotropic salt and dry superparamagnetic particles (PMPs) could be stored on-chip and reconstituted upon sample addition, simplifying the process of release of DNA from H. pylori cells and its binding to the PMPs. Finally, the PMPs were pulled via a magnet through a washing chamber containing an immiscible oil solution and into an elution chamber where the DNA was released into aqueous media for subsequent analysis. The entire process required only 7 min while enabling a 40-fold reduction in working volume from crude biological samples. The combination of a real-world interface and rapid DNA extraction offers the potential for the methodology to be used in point-of-care (POC) devices.

ANO1/TMEM16A interacts with EGFR and correlates with sensitivity to EGFR-targeting therapy in head and neck cancer

The epidermal growth factor receptor (EGFR) contributes to the pathogenesis of head&neck squamous cell carcinoma (HNSCC). However, only a subset of HNSCC patients benefit from anti-EGFR targeted therapy. By performing an unbiased proteomics screen, we found that the calcium-activated chloride channel ANO1 interacts with EGFR and facilitates EGFR-signaling in HNSCC. Using structural mutants of EGFR and ANO1 we identified the trans/juxtamembrane domain of EGFR to be critical for the interaction with ANO1. Our results show that ANO1 and EGFR form a functional complex that jointly regulates HNSCC cell proliferation. Expression of ANO1 affected EGFR stability, while EGFR-signaling elevated ANO1 protein levels, establishing a functional and regulatory link between ANO1 and EGFR. Co-inhibition of EGFR and ANO1 had an additive effect on HNSCC cell proliferation, suggesting that co-targeting of ANO1 and EGFR could enhance the clinical potential of EGFR-targeted therapy in HNSCC and might circumvent the development of resistance to single agent therapy. HNSCC cell lines with amplification and high expression of ANO1 showed enhanced sensitivity to Gefitinib, suggesting ANO1 overexpression as a predictive marker for the response to EGFR-targeting agents in HNSCC therapy. Taken together, our results introduce ANO1 as a promising target and/or biomarker for EGFR-directed therapy in HNSCC.

Abstract 1674: HER3 inhibition potentiates anti-tumor effects of PI3K inhibitors in pre-clinical models of HNSCC

Background: The phosphoinositide 3-kinase (PI3K) pathway is thought to be the most frequently mutated oncogenic pathway in head and neck squamous cell carcinoma (HNSCC). This pathway is often further activated by deregulated receptors such as the epidermal growth factor receptor family. HER3 has a direct phosphorylation site with the regulatory subunit of PIK3CA, and is being investigated as a potential co-target to increase anti-tumor effects of PI3K inhibition. In this investigation, we use blocking antibodies against HER3 and its ligand, neuregulin β-1, (KTN3379) and PIK3CA (BYL719) to investigate the effect of HER3 in modulating response to PI3K inhibition.

Methods and Results: Treatment with neuregulin β-1 significantly increased phosphorylation of HER3, AKT, and S6 across HNSCC, regardless of baseline level of HER3 expression. HER3 inhibition (KTN3379) consistently abrogated these effects, and decreased baseline phosphorylation of HER3. Combined blockade of HER3 (KTN3379) and PI3K (BYL719) inhibits the growth of HNSCC cell lines more effectively than inhibition of a single receptor alone, in both cell proliferation and colony formation assays. Combined treatment decreases phosphorylation of AKT and S6 more effectively than inhibition with either drug in some HNSCC cell lines. Treatment with neuregulin β-1 diminishes the inhibitory effect of BYL719 on HNSCC cell growth. Furthermore, treatment of some HNSCC cell lines with BYL719 led to upregulation of the HER3 pathway in HNSCC cell lines by Western blotting analysis, suggesting a possible role of HER3 in PI3K resistance.

Conclusion: HER3 interacts with PI3KCA, and the PI3K pathway in multiple HNSCC cell lines, and combined blockade leads to pronounced effects in pre-clinical models of HNSCC. These findings suggest that HER3 blockade, may be efficacious when combined with PI3K pathway inhibition.

Citation Format: Kara S. Davis, Nayel Khan, Carolyn Kemp, Sucheta Kulkarni, Diego Alvarado, Theresa LaVallee, Jennifer R. Grandis, Umamaheswar Duvvuri. HER3 inhibition potentiates anti-tumor effects of PI3K inhibitors in pre-clinical models of HNSCC. [abstract]. In: Proceedings of the 106th Annual Meeting of the American Association for Cancer Research; 2015 Apr 18-22; Philadelphia, PA. Philadelphia (PA): AACR; Cancer Res 2015;75(15 Suppl):Abstract nr 1674. doi:10.1158/1538-7445.AM2015-1674

Relationship between the body composition and motor and physical competence of Grade 1 learners in South Africa

AIM

The objective of this study was to determine relationships between body composition and motor and physical competence of Grade 1 learners living in the North West Province of South Africa.

METHODS

Data were collected by means of a stratified random sampling procedure from 816 Grade 1 learners (419 boys, 397 girls) with a mean age of 6.84 years (+ 0.39 SD), in the NW-CHILD-study. Height, weight, skinfolds (subscapular, triceps, calf) and waist circumference were measured. International cut-off values were used to classify the subjects in normal, overweight or obese categories. Motor and physical competence was measured by using the Bruiniks-Oseretsky Test of Motor Proficiency-2 SF and the Test of Gross Motor Development 2.

RESULTS

One out of 10 learners were overweight or obese. Fine motor precision, balance, running speed and agility and strength correlated significantly with BMI with no clear relationships with object control skills and upper limb-coordination.

CONCLUSION

A clear relationship was found between body composition and most of the motor and physical fitness competencies of Grade 1 learners. Intervention strategies to improve the body composition of overweight children and accompanying motor proficiency back logs and physical fitness deficiencies are recommended.

An autophagy-enhancing drug promotes degradation of mutant alpha1-antitrypsin Z and reduces hepatic fibrosis

In the classical form of alpha1-antitrypsin (AT) deficiency, a point mutation in AT alters the folding of a liver-derived secretory glycoprotein and renders it aggregation-prone. In addition to decreased serum concentrations of AT, the disorder is characterized by accumulation of the mutant alpha1-antitrypsin Z (ATZ) variant inside cells, causing hepatic fibrosis and/or carcinogenesis by a gain-of-toxic function mechanism. The proteasomal and autophagic pathways are known to mediate degradation of ATZ. Here we show that the autophagy-enhancing drug carbamazepine (CBZ) decreased the hepatic load of ATZ and hepatic fibrosis in a mouse model of AT deficiency-associated liver disease. These results provide a basis for testing CBZ, which has an extensive clinical safety profile, in patients with AT deficiency and also provide a proof of principle for therapeutic use of autophagy enhancers.

Association of estrogen receptor gene alpha polymorphisms with postmenopausal mammary density

Abstract #5003

Background: With the human genome studies, knowledge about polymorphisms started raising interest in a variety of fields and, in medicine, the evidence of direct action of polymorphisms on the arising and progression of diseases, disclosing the possibility of using them as disease predisposition markers. Substitutions, insertions or deletions which are transmitted through generations and reach frequencies equal or superior to 1% in the population are named polymorphisms. Knowing that the mammographic pattern is a multifactorial character, the objectives of this study were to evaluate a possible association of clinical characteristics and polymorphisms HaeIII, MspI and XbaI of the estrogen receptor gene alpha with postmenopausal mammary density. Materials and Methods: A prospective evaluation was made of 120 women who were not hormone therapy users and had no clinically or mammographically identified breast lesions. All of them underwent bilateral mammography, and the radiological density was determined by three independent observers, with two subjective evaluations based on the ACR-BIRADS® classification of mammographic patterns, 2003, and one computerized evaluation – the grey-scale histogram tool of the Adobe Photoshop® 7.0 software. Peripheral blood samples were obtained for DNA extraction, performed according to the GFX® Kit protocol from Amersham-Pharmacia. After DNA extraction, PCR-RFLP (Polymerase Chain Reaction - Restriction Fragment Length Polymorphism) was carried out for an analysis of the polymorphisms present in intron 1 (HaeIII and XbaI) and in exon 1 (MspI) of the estrogen receptor gene. Results: There was a high degree of concordance among the observers in the determination of mammary density (Kappa, Pearson and Spearman - p<0.001). The associations of clinical characteristics with mammary density were: age (p=0.04), body mass index (p<0.0001), age at menarche (p=0.02), age at menopause (p=0.120), age at first delivery (p=0.120), parity (p=0.09). The relation between the allele distribution of the polymorphisms and the density was: XbaI (p=0.02), HaeIII (p=0.65), and MspI (p=0.65). Conclusion: Polymorphism XbaI and the clinical factors age, menarche and body mass index showed to be associated with postmenopausal mammary density.

Citation Information: Cancer Res 2009;69(2 Suppl):Abstract nr 5003.

Prevalence of fibroadenomas in kidney-transplanted patients using cyclosporine A

Abstract #6078

Background: Fibroadenoma is the commonest benign tumor of female breast, classified as fibroepithelial neoplasia. It is frequent during reproductive years mainly in the 2nd and 3rd decades of life, coinciding with follicular maturation and steroidogenesis. With the beginning of the era of transplants the use of cyclosporine A was accepted by the medical community as potential lymphocyte T suppressant. In 1980 the first report on multiple breast fibroadenomas in renal transplant patients taking cyclosporine A was published. The imaging standard of fibroadenomas also seems to differ from usually found in asymptomatic patients: diameters are notably larger, lower longitudinal / anteroposterior diameter ratio and are more hyperechogenic.
 Objetive: To define the prevalence of breast fibroadenomas in kidney-transplanted patients taking cyclosporine A.
 Materials and Methods: Prevalence of breast fibroadenomas was determined in three groups of patients: 50 women with renal transplant taking cyclosporine A (Group 1); 51 women with renal transplant not taking cyclosporine A (Group 2) and 181 women without renal transplant (Control Group). Evaluation was performed by anamnesis, physical examination and breast ultrasonography. In the case of clinical or imaging suspicion of fibroadenoma, the diagnosis was confirmed by core needle biopsy or lumpectomy.
 Results: The groups were homogeneous regarding age, menstrual status and former breast cancer family history. Fourteen percent fibroadenomas were found in the renal transplant patient group taking cyclosporine A versus 2.0% in the renal transplant patient group not taking cyclosporine A, and 2.8% in the control group. Prevalence of breast fibroadenomas in renal transplant patients taking cyclosporine A was significantly higher than in those not taking the drug and than in the control group (p=0.001). Frequency of fibroadenomas of the control group and renal transplant patients not taking cyclosporine was similar (p=0.073). Multiplicity, bilaterality and greater nodule dimensions were observed more in renal transplant patients taking cyclosporine A, but there was no statistical significance among the groups.
 
 Conclusion: Breast fibroadenomas are more prevalent in the renal transplant patients taking cyclosporine A.

Citation Information: Cancer Res 2009;69(2 Suppl):Abstract nr 6078.

Lack of pharmacokinetic interactions of aliskiren, a novel direct renin inhibitor for the treatment of hypertension, with the antihypertensives amlodipine, valsartan, hydrochlorothiazide (HCTZ) and ramipril in healthy volunteers

Aliskiren is a novel, orally active direct renin inhibitor that lowers blood pressure alone and in combination with existing antihypertensive agents. As aliskiren does not affect cytochrome P450 enzyme activities, is minimally metabolised, and is not extensively protein bound, the potential for drug interactions is predicted to be low. Four open-label studies investigated the pharmacokinetic interactions between aliskiren 300 mg and the antihypertensive drugs amlodipine 10 mg (n = 18), valsartan 320 mg (n = 18), hydrochlorothiazide 25 mg (HCTZ, n = 22) and ramipril 10 mg (n = 17) in healthy subjects. In each study, subjects received multiple once-daily doses of aliskiren and the test antihypertensive drug alone or in combination in two dosing periods separated by a drug-free washout period. Plasma concentrations of drugs were determined by liquid chromatography and mass spectrometry methods. At steady state, relatively small changes in exposure to aliskiren were observed when aliskiren was co-administered with amlodipine (AUC(tau) increased by 29%, p = 0.032), ramipril (C(max,ss) increased by 31%, p = 0.043), valsartan (AUC(tau) decreased by 26%, p = 0.002) and HCTZ (C(max,ss) decreased by 22%, p = 0.039). Co-administration with aliskiren resulted in small changes in exposure to ramipril (AUC(tau) increased by 22%, p = 0.002), valsartan (AUC(tau) decreased by 14%, p = 0.062) and HCTZ (AUC(tau) decreased by 10% and C(max,ss) by 26%, both p < 0.001). All other changes in pharmacokinetic parameters were also small, and not statistically significant. None of the observed pharmacokinetic changes was considered clinically relevant. Aliskiren inhibited plasma renin activity (PRA) and also prevented the reactive rise in PRA induced by valsartan. The most commonly reported adverse events were headache, dizziness and gastrointestinal symptoms (all mild in severity), which were similar in frequency during antihypertensive drug treatment alone and in combination with aliskiren except for an increase in dizziness during treatment with the combination of aliskiren and HCTZ. In conclusion, aliskiren shows no clinically relevant pharmacokinetic interactions and is generally well tolerated when administered in combination with amlodipine, valsartan, HCTZ or ramipril.

Infectious diseases of refugees and immigrants: dengue fever

PURPOSE

To describe the assessment and management of chronic wounds and detail current recommendations for optimal wound care practices.

DATA SOURCES

Selected scientific literature, clinical practice guidelines, and the authors' clinical experience.

CONCLUSION

Multiple factors play a role in the problems associated with chronic wounds. Wound care is costly in regards to medical care, as well as costly in terms of the hardship placed on the patient, family and staff. Too often, wound care practices are based on rituals than research.

IMPLICATIONS FOR PRACTICE

The assessment and management of chronic wounds needs to be individualized according to a thorough assessment of the wound, the patients' lifestyle, and the caregiver's knowledge and skill for managing th wound. It is also important to know what wound care products are available and the types of wounds appropriate for their use.

Polyvalent envelope glycoprotein vaccine elicits a broader neutralizing antibody response but is unable to provide sterilizing protection against heterologous Simian/human immunodeficiency virus infection in pigtailed macaques

The great difficulty in eliciting broadly cross-reactive neutralizing antibodies (NAbs) against human immunodeficiency virus type 1 (HIV-1) isolates has been attributed to several intrinsic properties of their viral envelope glycoprotein, including its complex quaternary structure, extensive glycosylation, and marked genetic variability. Most previously evaluated vaccine candidates have utilized envelope glycoprotein from a single virus isolate. Here we compare the breadth of NAb and protective immune response following vaccination of pigtailed macaques with envelope protein(s) derived from either single or multiple viral isolates. Animals were challenged with Simian/human immunodeficiency virus strain DH12 (SHIV(DH12)) following priming with recombinant vaccinia virus(es) expressing gp160(s) and boosting with gp120 protein(s) from (i) LAI, RF, 89.6, AD8, and Bal (Polyvalent); (ii) LAI, RF, 89.6, AD8, Bal, and DH12 (Polyvalent-DH12); (iii) 89.6 (Monovalent-89.6); and (iv) DH12 (Monovalent-DH12). Animals in the two polyvalent vaccine groups developed NAbs against more HIV-1 isolates than those in the two monovalent vaccine groups (P = 0.0054). However, the increased breadth of response was directed almost entirely against the vaccine strains. Resistance to SHIV(DH12) strongly correlated with the level of NAbs directed against the virus on the day of challenge (P = 0.0008). Accordingly, the animals in the Monovalent-DH12 and Polyvalent-DH12 vaccine groups were more resistant to the SHIV(DH12) challenge than the macaques immunized with preparations lacking a DH12 component (viz. Polyvalent and Monovalent-89.6) (P = 0.039). Despite the absence of any detectable NAb, animals in the Polyvalent vaccine group, but not those immunized with Monovalent-89.6, exhibited markedly lower levels of plasma virus than those in the control group, suggesting a superior cell-mediated immune response induced by the polyvalent vaccine.

Four linked outbreaks of Salmonella enteritidis phage type 4 infection--the continuing egg threat

Four outbreaks of Salmonella enteritidis phage type (PT) 4 occurred among guests at functions for which a single commercial caterer supplied food. Retrospective cohort studies were used to describe the epidemiology of three of these outbreaks and identify the vehicle(s) responsible. Of 172 guests at these three events, 47 fitted the clinical case definition for illness and 24 cases were confirmed to have S. enteritidis PT4 infection. Food containing raw egg was identified epidemiologically as the likely vehicle of infection in two of the three outbreaks (odds ratios (OR) and 95% confidence intervals 9.1 (2.2-39.9) and 6.9 (1.2-46.4)). Logistic regression analysis yielded OR = 10.7 (p = 0.0022) and OR = 9.3 (p = 0.015) for egg consumption in two of the outbreaks. These outbreaks highlighted the continuing need to remind the public and commercial caterers of the potential high risks of contracting salmonella from shell eggs. Education of caterers includes advice to obtain eggs and other products from reputable and identifiable suppliers.

Mouse paraxial protocadherin is expressed in trunk mesoderm and is not essential for mouse development

Paraxial protocadherin (PAPC) is a cell adhesion molecule that marks cells undergoing convergence-extension cell movements in Xenopus and zebrafish gastrulating embryos. Here a mouse homologue (mpapc) was identified and characterized. During early- to mid-gastrulation, mpapc is expressed in the primitive streak as the trunk mesoderm undergoes morphogenetic cell movements. At head-fold stage mpapc expression becomes localized to paraxial regions in which somites are formed in the segmental plate. At later stages, mpapc displays a complex expression pattern in cerebral cortex, olfactory bulb, inferior colliculus, and in longitudinal stripes in hindbrain. To analyze the effect of the loss of PAPC function during mouse development, a null allele of the mouse papc gene was generated. Homozygous animals show no defects in their skeleton and are viable and fertile.

The crystal structure of palmitoyl protein thioesterase 1 and the molecular basis of infantile neuronal ceroid lipofuscinosis

Mutations in palmitoyl-protein thioesterase 1 (PPT1), a lysosomal enzyme that removes fatty acyl groups from cysteine residues in modified proteins, cause the fatal inherited neurodegenerative disorder infantile neuronal ceroid lipofuscinosis. The accumulation of undigested substrates leads to the formation of neuronal storage bodies that are associated with the clinical symptoms. Less severe forms of PPT1 deficiency have been found recently that are caused by a distinct set of PPT1 mutations, some of which retain a small amount of thioesterase activity. We have determined the crystal structure of PPT1 with and without bound palmitate by using multiwavelength anomalous diffraction phasing. The structure reveals an alpha/beta-hydrolase fold with a catalytic triad composed of Ser115-His289-Asp233 and provides insights into the structural basis for the phenotypes associated with PPT1 mutations.

Cerberus-like is a secreted BMP and nodal antagonist not essential for mouse development

Mouse cerberus-like (cer-l) is a member of the Cerberus/Dan family of secreted factors. As other members of this family of proteins, Cer-l functions in the extracellular space, inhibiting signaling molecules. Here we show that the neural-inducing and mesoderm-inhibiting activities of Cer-l result from specific binding to BMP and Nodal molecules, respectively. These properties resemble the ones from the related factor Xenopus Cerberus. However, Xenopus Cerberus in addition to BMP4 and Nodal also binds to and inhibits Wnt proteins. We show that Cer-l does not directly inhibit Wnt signals. A null allele of the mouse Cer-l gene was generated by targeted inactivation in ES cells. Homozygous embryos show no anterior patterning defects, are born alive, and are fertile. Since mouse Cer-l and Xenopus Cerberus differ in biochemical activities, we propose the existence of additional members of this family of inhibitors, which may compensate for the loss of cer-l.

Endodermal Nodal-related signals and mesoderm induction in Xenopus

In Xenopus, mesoderm induction by endoderm at the blastula stage is well documented, but the molecular nature of the endogenous inductive signals remains unknown. The carboxy-terminal fragment of Cerberus, designated Cer-S, provides a specific secreted antagonist of mesoderm-inducing Xenopus Nodal-Related (Xnr) factors. Cer-S does not inhibit signalling by other mesoderm inducers such as Activin, Derriere, Vg1 and BMP4, nor by the neural inducer Xnr3. In the present study we show that Cer-S blocks the induction of both dorsal and ventral mesoderm in animal-vegetal Nieuwkoop-type recombinants. During blastula stages Xnr1, Xnr2 and Xnr4 are expressed in a dorsal to ventral gradient in endodermal cells. Dose-response experiments using cer-S mRNA injections support the existence of an endogenous activity gradient of Xnrs. Xnr expression at blastula can be activated by the vegetal determinants VegT and Vg1 acting in synergy with dorsal (beta)-catenin. The data support a modified model for mesoderm induction in Xenopus, in which mesoderm induction is mediated by a gradient of multiple Nodal-related signals released by endoderm at the blastula stage.

Malignant phyllodes tumor in the right breast and invasive lobular carcinoma within fibroadenoma in the other: case report

CONTEXT

The malignant variety of the phyllodes tumor is rare. The occurrence of invasive lobular carcinoma within fibroadenoma is rare as well.

DESIGN

Case report.

CASE REPORT

A 58-year-old black female patient was referred to the Mastology unit of the Department of Gynecology, Federal University of São Paulo / Escola Paulista de Medicina, in February 1990, presenting an ulcerated tumor in the right breast with fast growth over the preceding six months. She was a virgin, with meno-pause at the age of 45 years and had not undergone hormone replacement treatment. The physical examination showed, in her right breast, an ulcerated tumor of 20 x 30 cm which was not adher-ent to the muscle level, multilobular and with fibroelastic consistency. The axillary lymph nodes were not palpable. The left breast showed a 2 x 3 cm painless, movable nodule, with well-defined edges, and fibroelastic consistency. We performed left-breast mammography, which showed several nodules with well-defined edges, the largest being 2 x 3 cm and exhibiting rough calcification and grouped microcalcifications within it. The patient underwent a frozen biopsy that showed a malignant variant of the phyllodes tumor in the right breast and fibroadenoma in the left one. After that, we performed a total mastectomy in the right breast and an excision biopsy in the left one. Paraffin study confirmed the frozen biopsy result from the right breast, yet we observed that in the interior of the fibroadenoma that was removed on the left, there was a focal area of invasive lobular carcinoma measuring 0.4 cm. The patient then underwent a modi-fied radical mastectomy with total axillary lymphadenectomy. None of the 21 dissected lymph nodes showed evidence of metastasis. In the follow-up, the patient evolved asymptomatically and with normal physical and laboratory examination results up to July 1997.