Molecular Epidemiology of Influenza A(H1N1)pdm09 Virus among Humans and Swine,Sri Lanka

After multiple discrete introductions of influenza A(H1N1)pdm09 virus into Sri Lanka, the virus was transmitted among humans, then swine. The spread of virus between geographically distant swine farms is consistent with virus dispersal associated with a vehicle used for swine transportation, although this remains unproven.     

Daidzein,R-(+)equol and S-(−)equol inhibit the invasion of MDA-MB-231 breast cancer cells potentially via the down-regulation of matrix metalloproteinase-2

Purpose

Soy isoflavones may inhibit tumor cell invasion and metastasis via their effects on matrix metalloproteinases (MMPs) and their tissue inhibitors (TIMPs). The current study investigates the effects of daidzein, R- and S-equol on the invasion of MDA-MB-231 human breast cancer cells and the effects of these compounds on MMP/TIMP expression at the mRNA level.

Methods

The anti-invasive effects of daidzein, R- and S-equol (0, 2.5, 10, 50 μM) on MDA-MB-231 cells were determined using the Matrigel invasion assay following 48-h exposure. Effects on MMP-2, MMP-9, TIMP-1 and TIMP-2 expression were assessed using real-time PCR. Chiral HPLC analysis was used to determine intracellular concentrations of R- and S-equol.

Results

The invasive capacity of MDA-MB-231 cells was significantly reduced (by approximately 50–60 %) following treatment with 50 μM daidzein, R- or S-equol. Anti-invasive effects were also observed with R-equol at 2.5 and 10 μM though overall equipotent effects were induced by all compounds. Inhibition of invasion induced by all three compounds at 50 μM was associated with the down-regulation of MMP-2, while none of the compounds tested significantly affected the expression levels of MMP-9, TIMP-1 or TIMP-2 at this concentration. Following exposure to media containing 50 μM R- or S-equol for 48-h intracellular concentrations of R- and S-equol were 4.38 ± 1.17 and 3.22 ± 0.47 nM, respectively.

Conclusion

Daidzein, R- and S-equol inhibit the invasion of MDA-MB-231 human breast cancer cells in part via the down-regulation of MMP-2 expression, with equipotent effects observed for the parent isoflavone daidzein and the equol enantiomers.     

Homocysteine,antioxidant micronutrients and late onset dementia

Purpose

To distinguish between contributions to dementia made by homocysteine, folate, B12 and antioxidant micronutrients.

Methods

This is a follow-up study of a sample reported in 2002. Homocysteine was measured at baseline in 201 individuals born in 1921 and without dementia at age 77 years and followed up to age 88 years. Baseline macro- and micronutrient status was estimated from BMI, the MONICA food frequency questionnaire, plasma folate, B12 and, in a subgroup (N = 173), plasma antioxidant micronutrients. Time to dementia onset during follow-up was compared between participants grouped by homocysteine concentration using Cox regression. Model 1 adjusted for age, sex, childhood IQ, education, socioeconomic deprivation, presence of heart disease, hypertension, plasma folate and B12. In model 2 plasma, antioxidants were added to these covariables.

Results

During a mean follow-up of about 5 years, there were 39 incident dementia cases among 201 participants. In model 1, being in the highest homocysteine group (>14 μmol/L) was associated with a 234 % increased risk (HR 3.34, 95 % CI 1.16–9.57) of any dementia. After inclusion of plasma antioxidants in model 2, there were 32 incident dementia cases from a subsample (N = 173). Homocysteine >14 μmol was associated with a 272 % increased dementia risk (HR = 3.72, 95 % CI 1.06–13.08).

Conclusions

High homocysteine increases the risk of dementia. The association between tHcy and dementia is independent of plasma folate, B12 and antioxidant micronutrient status.     

Are Quadrilateral Surface Buttress Plates Comparable to Traditional Forms of Transverse Acetabular Fracture Fixation?

Background

Several construct options exist for transverse acetabular fracture fixation. Accepted techniques use a combination of column plates and lag screws. Quadrilateral surface buttress plates have been introduced as potential fixation options, but as a result of their novelty, biomechanical data regarding their stabilizing effects are nonexistent. Therefore, we aimed to determine if this fixation method confers similar stability to traditional forms of fixation.

Questions/purposes

We biomechanically compared two acetabular fixation plates with quadrilateral surface buttressing with traditional forms of fixation using lag screws and column plates.

Methods

Thirty-five synthetic hemipelves with a transverse transtectal acetabular fracture were allocated to one of five groups: anterior column plate + posterior column lag screw, posterior column plate + anterior column lag screw, anterior and posterior column lag screws only, infrapectineal plate + anterior column plate, and suprapectineal plate alone. Specimens were loaded for 1500 cycles up to 2.5x body weight and stiffness was calculated. Thereafter, constructs were destructively loaded and failure loads were recorded.

Results

After 1500 cycles, final stiffness was not different with the numbers available between the infrapectineal (568 ± 43 N/mm) and suprapectineal groups (602 ± 87 N/mm, p = 0.988). Both quadrilateral plates were significantly stiffer than the posterior column buttress plate with supplemental lag screw fixation group (311 ± 99 N/mm, p < 0.006). No difference in stiffness was identified with the numbers available between the quadrilateral surface plating groups and the lag screw group (423 ± 219 N/mm, p > 0.223). The infrapectineal group failed at the highest loads (5.4 ± 0.6 kN) and this was significant relative to the suprapectineal (4.4 ± 0.3 kN; p = 0.023), lag screw (2.9 ± 0.8 kN; p < 0.001), and anterior buttress plate with posterior column lag screw (4.0 ± 0.6 kN; p = 0.001) groups.

Conclusions

Quadrilateral surface buttress plates spanning the posterior and anterior columns are biomechanically comparable and, in some cases, superior to traditional forms of fixation in this synthetic hemipelvis model.

Clinical Relevance

Quadrilateral surface buttress plates may present a viable alternative for the treatment of transtectal transverse acetabular fractures. Clinical studies are required to fully define the use of this new form of fixation for such fractures when accessed through the anterior intrapelvic approach.     

Decision making in the management of recurrent head and neck cancer

Despite substantial improvements in head and neck squamous cell carcinoma (HNSCC) treatment, the major obstacle to long‐term survival remains disease recurrence. Salvage options are often limited due to prior therapy and the escalated morbidity of retreatment. The costs of treatment must be measured against the anticipated quality and quantity of life recovered, even with resectable disease. This review surveys the recurrent HNSCC literature to better guide decision making. Across multiple studies, negative prognostic factors include impaired performance status, advanced recurrent stage, brief disease‐free interval, previous chemotherapy, and nonlaryngeal sites of recurrence. When possible, surgical salvage remains the principal option for durable disease control, quality of life preservation, and cure. Nonsurgical therapies have also demonstrated measurable improvements in locoregional control. Interpretation of salvage literature must be tempered by recognition of significant selection bias. The decision for salvage therapy must be individualized, with management that involves well‐informed patients resulting in the best outcomes. © 2013 Wiley Periodicals, Inc. Head Neck 36 : 144–151, 2014