The impact of transmission clusters on primary drug resistance in newly diagnosed HIV-1 infection.

OBJECTIVES: To monitor HIV-1 transmitted drug resistance (TDR) in a well defined urban area with large access to antiretroviral therapy and to assess the potential source of infection of newly diagnosed HIV individuals. METHODS: All individuals resident in Geneva, Switzerland, with a newly diagnosed HIV infection between 2000 and 2008 were screened for HIV resistance. An infection was considered as recent when the positive test followed a negative screening test within less than 1 year. Phylogenetic analyses were performed by using the maximum likelihood method on pol sequences including 1058 individuals with chronic infection living in Geneva. RESULTS: Of 637 individuals with newly diagnosed HIV infection, 20% had a recent infection. Mutations associated with resistance to at least one drug class were detected in 8.5% [nucleoside reverse transcriptase inhibitors (NRTIs), 6.3%; non-nucleoside reverse transcriptase inhibitors (NNRTIs), 3.5%; protease inhibitors, 1.9%]. TDR (P-trend = 0.015) and, in particular, NNRTI resistance (P = 0.002) increased from 2000 to 2008. Phylogenetic analyses revealed that 34.9% of newly diagnosed individuals, and 52.7% of those with recent infection were linked to transmission clusters. Clusters were more frequent in individuals with TDR than in those with sensitive strains (59.3 vs. 32.6%, respectively; P < 0.0001). Moreover, 84% of newly diagnosed individuals with TDR were part of clusters composed of only newly diagnosed individuals. CONCLUSION: Reconstruction of the HIV transmission networks using phylogenetic analysis shows that newly diagnosed HIV infections are a significant source of onward transmission, particularly of resistant strains, thus suggesting an important self-fueling mechanism for TDR.

Le cancer du sein sans envahissement ganglionnaire. Au-delà des consensus internationaux: une approche pragmatique [Node negative breast cancer. Beyond international consensus: a pragmatic approach].

Apart from therapeutic advances related to new treatments, our practices in the management of early breast cancer have been modified by to key organizational settings (1) mass screening, substantially altering the presentation and epidemiology of breast cancer and (2) the development of guidelines to ensure that any patient management is in agreement with the demonstrated impact in the adjuvant treatment. In daily practice, the impact of screening and guidelines recommendations has put us now in a paradoxical situation: while the majority of non-metastatic breast cancers treated in the hexagon are node negative, most of the results of clinical studies on chemotherapy and targeted therapies today arise from populations predominantly node positive. Therefore, it seemed legitimate to convene a working group around a reflection on the directions of adjuvant chemotherapy in a growing node negative population in order to better respond to the questions of the field oncologists, trying to address the discrepancies between different existing guidelines.

Targeted Small Business Link, Spring 2011, Vol. 4, no. 2

Targeted Small Business News from the Iowa Department of Economic Development, Spring 2011, Volume 4, Number 2

Targeted nasal vaccination provides antibody-independent protection against Staphylococcus aureus.

Despite showing promise in preclinical models, anti-Staphylococcus aureus vaccines have failed in clinical trials. To date, approaches have focused on neutralizing/opsonizing antibodies; however, vaccines exclusively inducing cellular immunity have not been studied to formally test whether a cellular-only response can protect against infection. We demonstrate that nasal vaccination with targeted nanoparticles loaded with Staphylococcus aureus antigen protects against acute systemic S. aureus infection in the absence of any antigen-specific antibodies. These findings can help inform future developments in staphylococcal vaccine development and studies into the requirements for protective immunity against S. aureus.

Drug adherence in chronic kidney diseases and dialysis.

Poor long-term adherence and persistence to drug therapy is universally recognized as one of the major clinical issues in the management of chronic diseases, and patients with renal diseases are also concerned by this important phenomenon. Chronic kidney disease (CKD) patients belong to the group of subjects with one of the highest burdens of daily pill intake with up to >20 pills per day depending on the severity of their disease. The purpose of the present review is to discuss the difficulties encountered by nephrologists in diagnosing and managing poor adherence and persistence in CKD patients including in patients receiving maintenance dialysis. Our review will also attempt to provide some clues and new perspectives on how drug adherence could actually be addressed and possibly improved. Working on drug adherence may look like a long and tedious path, but physicians and healthcare providers should always be aware that drug adherence is in general much lower than what they may think and that there are many ways to improve and support drug adherence and persistence so that renal patients obtain the full benefits of their treatments.

Ocular gene therapy: a review of nonviral strategies.

Along with viral vectors, non-viral strategies have been developed in order to efficiently deliver nucleic acids to ocular cells. During the last decade, we have observed that the outcome of these non-viral delivery systems depends on the genetic material used, the targeted tissue or cells, the expected effect duration, and the routes of administration. Assessment of efficiency has been evaluated in normal eyes or in animal models of ocular diseases. The chemical and physical methods that have been adapted for the delivery of nucleic acids to ocular tissues are highlighted and discussed in this review. Also, the results obtained with different non-viral strategies from their initial conception to their present development are summarized. At the present, selective targeting of ocular tissues and cells can be achieved using the most yielding route of administration to the eye in combination with an appropriate drug delivery technique.

Treatment-Naive Individuals Are the Major Source of Transmitted HIV-1 Drug Resistance in Men Who Have Sex With Men in the Swiss HIV Cohort Study.

Background. Human immunodeficiency virus type 1 (HIV-1) transmitted drug resistance (TDR) can compromise antiretroviral therapy (ART) and thus represents an important public health concern. Typically, sources of TDR remain unknown, but they can be characterized with molecular epidemiologic approaches. We used the highly representative Swiss HIV Cohort Study (SHCS) and linked drug resistance database (SHCS-DRDB) to analyze sources of TDR. Methods. ART-naive men who have sex with men with infection date estimates between 1996 and 2009 were chosen for surveillance of TDR in HIV-1 subtype B (N = 1674), as the SHCS-DRDB contains pre-ART genotypic resistance tests for >69% of this surveillance population. A phylogeny was inferred using pol sequences from surveillance patients and all subtype B sequences from the SHCS-DRDB (6934 additional patients). Potential sources of TDR were identified based on phylogenetic clustering, shared resistance mutations, genetic distance, and estimated infection dates. Results. One hundred forty of 1674 (8.4%) surveillance patients carried virus with TDR; 86 of 140 (61.4%) were assigned to clusters. Potential sources of TDR were found for 50 of 86 (58.1%) of these patients. ART-naive patients constitute 56 of 66 (84.8%) potential sources and were significantly overrepresented among sources (odds ratio, 6.43 [95% confidence interval, 3.22-12.82]; P < .001). Particularly large transmission clusters were observed for the L90M mutation, and the spread of L90M continued even after the near cessation of antiretroviral use selecting for that mutation. Three clusters showed evidence of reversion of K103N or T215Y/F. Conclusions. Many individuals harboring viral TDR belonged to transmission clusters with other Swiss patients, indicating substantial domestic transmission of TDR in Switzerland. Most TDR in clusters could be linked to sources, indicating good surveillance of TDR in the SHCS-DRDB. Most TDR sources were ART naive. This, and the presence of long TDR transmission chains, suggests that resistance mutations are frequently transmitted among untreated individuals, highlighting the importance of early diagnosis and treatment.

Pitfalls in cefepime titration from human plasma: plasma- and temperature-related drug degradation in vitro.

While developing a high-pressure liquid chromatography assay for cefepime in plasma, we observed significant drug degradation at 20 and 37 degrees C but not at 4 degrees C. This plasma-related degradation persisted after protein removal. This warrants caution regarding cefepime assays for pharmacokinetic and pharmacodynamic studies of cefepime in vitro and in vivo.

Nouveaux traitements de l'hépatite C: aspects pharmacologiques et potentiel d'interaction [New hepatitis C treatments: pharmacological considerations and potential for drug interactions].

Progress in the understanding of the hepatitis C virus life cycle allowed the development of new, very promising antiviral therapies. Although these new drugs have a favourable profile in terms of efficacy, tolerance and interaction potential, their prescription in the setting of comedication and impaired renal or hepatic function remains a challenge. Here, we provide a summary of pharmacological considerations, focusing on sofosbuvir, simeprevir and daclatasvir. A better understanding of their metabolic pathways and transporters may help the prescriber to identify and manage drug interactions especially in patients under immunosuppressive or anti-HIV therapy. Recommendations for the prescription of these drugs in specific situations are also discussed.

Targeted Small Business Link, Summer 2011, Vol. 4, no. 3

Targeted Small Business News and information from the Iowa Department of Economic Development.