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    <recommendedItem id="20100101_19_432"
                     title="Short Needle May Short HBV Protection for Obese (CME/CE)"
                     score="0.012"
                     href="http://www.medpagetoday.com/Pediatrics/Vaccines/tb/18348?impressionId=1265761610745"
                     
      &lt;p&gt;Obese adolescents and young adults may not generate an adequate immune response to hepatitis B (HBV) vaccine because the needles used to vaccinate them are too short, a randomized study suggests.&lt;/p&gt;
&lt;p&gt;Immunization with a 1.5-inch needle was associated with 80% higher anti-HBV titers than a 1.0-inch needle, researchers reported online in &lt;em&gt;Pediatrics.&lt;/em&gt;&lt;/p&gt;
&lt;p&gt;The difference persisted in analyses performed to correct for imbalances in the study population.&lt;/p&gt;
&lt;p&gt;&quot;This supports the hypothesis that inadequate muscle penetration is responsible, at least in part, for lower immune response to HBV vaccine among obese adolescent and adult vaccine recipients,&quot; Amy Middleman, MD, of Baylor College of Medicine in Houston, and colleagues concluded.&lt;/p&gt;
&lt;p&gt;Several studies have shown that adolescents and adults with a higher body mass index (BMI) have lower antibody titers after HBV vaccination. The observations have taken on new significance, given that an increasing number of vaccines target a population that has a rising BMI, the authors wrote.&lt;/p&gt;
&lt;p&gt;Researchers hypothesize that standard-length needles do not penetrate through the deltoid fat and into the muscle of obese adolescents and adults. Because of its less abundant blood supply, adipose tissue may delay antigen presentation to B and T cells responsible for immune response, the authors continued.&lt;/p&gt;
&lt;p&gt;To test the hypothesis, Middleman and colleagues conducted a randomized, clinical trial involving adolescents and adults ages 14 to 24 with no prior exposure to HBV vaccine. Eligibility criteria included weight &amp;gt;90 kg for female patients and &amp;gt;120 kg for male patients.&lt;/p&gt;
&lt;p&gt;Patients were randomized to receive the HBV vaccine series with a standard one-inch needle or a 1.5-inch needle. Patients younger than 19 received 0.5-mL injections, and older patients received 1.0-mL injections.&lt;/p&gt;
&lt;p&gt;Investigators used a standardized injection procedure: insertion of the needle at a 90&amp;#176; angle to the deltoid muscle, leaving 2 to 3 mm of needle visible between the skin and the hub.&lt;/p&gt;
&lt;p&gt;Patients received three doses of vaccine at baseline, one month, and four months. Blood samples were obtained at baseline and two months after the final injection.&lt;/p&gt;
&lt;p&gt;The two groups did not differ significantly with respect to median age (21), BMI (~40), deltoid skinfold (41 mm), triceps skinfold (~40 mm), days between vaccine doses one and three (~135), and days from third vaccine dose to titer assessment (65).&lt;/p&gt;
&lt;p&gt;At the end of the study, 24 patients had completed the immunization protocol, 10 in the one-inch group and 14 in the 1.5-inch group.&lt;/p&gt;
&lt;p&gt;Patients vaccinated with a one-inch needle had a median antibody titer of 189.8 mIU/mL compared with 345.4 mIU/mL for patients vaccinated with the 1.5-inch needle (&lt;em&gt;P&lt;/em&gt;=0.03).&lt;/p&gt;
&lt;p&gt;The between-group difference remained significant in analyses that excluded an outlier from the 1.5-inch group (&lt;em&gt;P&lt;/em&gt;=0.047) and that excluded the only two male patients in the study (&lt;em&gt;P&lt;/em&gt;=0.035).&lt;/p&gt;
&lt;p&gt;&quot;As we continue to experience high rates of obesity in the U.S. and throughout the world, additional evidence-based research on optimizing the effective delivery of immunizations to adolescents and young adults will be critical,&quot; the authors wrote.&lt;/p&gt;
&lt;p&gt;&quot;Following updated needle length recommendations will be a first step toward improving the health of our youth and young adults by preventing vaccine-preventable diseases.&quot;&lt;/p&gt;
&lt;div style=&quot;float:left;border-style:solid;border-width:1px;border-color:#8dabbc;font-family:arial;font-size:12px;background-color:#DBE9F2;padding:5px;&quot;&gt;&lt;p&gt;The study was supported by federal grants and awards. GlaxoSmithKline provided the vaccine.&lt;/p&gt;&lt;p&gt;The authors had no disclosures.&lt;/p&gt;&lt;/div&gt;&lt;div style=&quot;clear:both;&quot;&gt;&lt;/div&gt;
    </recommendedItem>
    <recommendedItem id="20100101_19_277"
                     title="Liver Cell Culture System Might Test New HCV Drugs (CME/CE)"
                     score="0.003"
                     href="http://www.medpagetoday.com/InfectiousDisease/Hepatitis/tb/18133?impressionId=1265761610745"
                     
      &lt;p&gt;Researchers say they can now grow liver cells that maintain their functions long enough to test potential treatments for hepatitis C.&lt;/p&gt;
&lt;p&gt;The method uses so-called &quot;micropatterned co-cultures&quot; of primary human hepatocytes and supportive stroma, according to Sangeeta N. Bhatia, MD, PhD, of MIT, and colleagues.&lt;/p&gt;
&lt;p&gt;The co-cultures were able to support the entire life cycle of hepatitis C, including infection and replication, Bhatia and colleagues reported online in the &lt;em&gt;Proceedings of the National Academy of Sciences&lt;/em&gt;.&lt;/p&gt;
&lt;p&gt;Coupled with reporter systems, the co-cultures have &quot;potential as a high-throughput platform for simultaneous assessment of in vitro efficacy and toxicity&quot; of antiviral drugs, the researchers said.&lt;/p&gt;
&lt;p&gt;The lack of such a system has been a roadblock to testing potential treatments for the virus, which affects 130 million people around the world, the researchers noted in the journal.&lt;/p&gt;
&lt;p&gt;Recently, they added, researchers have been able to propagate the virus in human hepatoma cells, but those cells, among other issues, proliferate abnormally and have disturbed gene expression.&lt;/p&gt;
&lt;p&gt;To overcome those obstacles, the researchers turned to primary hepatocytes, which would make a better test system, except that they are notoriously hard to maintain in culture.&lt;/p&gt;
&lt;p&gt;To form the co-cultures, Bhatia and colleagues seeded multi-well plates with human hepatocytes, followed several hours later by murine fibroblasts.&lt;/p&gt;
&lt;p&gt;&quot;If you just put cells on a surface in an unorganized way, they lose their function very quickly,&quot; Bhatia said in a statement. &quot;If you specify which cells sit next to each other, you can extend the lifetime of the cells and help them maintain their function.&quot;&lt;/p&gt;
&lt;p&gt;In a series of experiments, Bhatia and colleagues found:&lt;ul&gt; &lt;li&gt;Pseudoparticles bearing the hepatitis C glycoproteins E1 and E2 were able to infect between 1% and 3% of the hepatocytes, but did not infect the fibroblasts.&lt;/li&gt; &lt;li&gt;A hepatitis C virus modified to express a fluorescent protein persistently replicated over a two-week period.&lt;/li&gt; &lt;li&gt;Infectious virus was found in the co-culture supernatant from four through 12 days after initial infection.&lt;/li&gt; &lt;/ul&gt;&lt;/p&gt;
&lt;p&gt;The researchers also tested some possible therapeutics, including antibodies against viral entry factors and viral protease inhibitors, and were able to show effects on replication of hepatitis C.&lt;/p&gt;
&lt;p&gt;They were also able to test two or more drugs simultaneously to show the feasibility of combination drug studies using the system.&lt;/p&gt;
&lt;p&gt;Although the system is &quot;an important step forward,&quot; Bhatia and colleagues said, the co-cultures have some limitations, including the relatively inefficient uptake of virus.&lt;/p&gt;
&lt;p&gt;But they concluded that the co-cultures have the potential to be a &quot;highly valuable system for studies of (hepatitis C) biology.&quot;&lt;/p&gt;
&lt;div style=&quot;float:left;border-style:solid;border-width:1px;border-color:#8dabbc;font-family:arial;font-size:12px;background-color:#DBE9F2;padding:5px;&quot;&gt;&lt;p&gt;This study had support from the Greenberg Medical Research Institute, the Ellison Medical Foundation, the Starr Foundation, the Ronald A. Shellow Memorial Fund, the Richard Salomon Family Foundation, and the NIH. The researchers said they had no conflicts.&lt;/p&gt;&lt;/div&gt;&lt;div style=&quot;clear:both;&quot;&gt;&lt;/div&gt;
    </recommendedItem>
    <recommendedItem id="20100101_19_183"
                     title="Gastric Bypass Extends Life for Most Patients (CME/CE)"
                     score="-0.004"
                     href="http://www.medpagetoday.com/PrimaryCare/Obesity/tb/18020?impressionId=1265761610745"
                     
      &lt;p&gt;For most patients in most categories, bariatric surgery increases life expectancy, according to a new mathematical model.&lt;/p&gt;
&lt;p&gt;Only when short-term mortality following bariatric surgery is expected to be high or the likelihood of success is low will the procedure fail to improve life expectancy, researchers reported in the January &lt;em&gt;Archives of Surgery&lt;/em&gt;.&lt;/p&gt;
&lt;p&gt;Computer modeling predicted that a hypothetical &quot;base case&quot; patient  --  a 42-year-old woman with a body mass index of 45  --  would gain 2.95 years of additional survival following bariatric surgery, according to Daniel P. Schauer, MD, of the University of Cincinnati, and colleagues.&lt;/p&gt;
&lt;p&gt;Surgery failed to be beneficial in the model only when 30-day mortality reached 9.5% or the likelihood that surgery would not add life-years was 2% or less, they found.&lt;/p&gt;
&lt;p&gt;Baseline 30-day mortality in the model was 0.2%, and the baseline efficacy of surgery in extending life expectancy was 53%.&lt;/p&gt;
&lt;p&gt;&quot;While not all patients are guaranteed a good outcome, our model indicates that gastric bypass increases life expectancy for most patient subgroups,&quot; they concluded.&lt;/p&gt;
&lt;p&gt;Their analysis was based on a Markov decision model using published data to estimate 30-day mortality following bariatric surgery and the efficacy of surgery in reducing long-term death rates.&lt;/p&gt;
&lt;p&gt;The latter had two components: reduction in excess mortality associated with obesity, and research data on long-term mortality following bariatric surgery.&lt;/p&gt;
&lt;p&gt;Excess mortality estimates came from National Health Interview Survey data on some 400,000 participants from 1991 to 1996 linked to the National Death Index. Inputs on surgery efficacy were derived from a 2007 study of nearly 8,000 patients who had undergone gastric bypass and the same number of medically treated or untreated obese controls.&lt;/p&gt;
&lt;p&gt;That study found that the procedure cut death rates by half during about seven years of follow-up. (See &lt;a href=&quot;http://www.medpagetoday.com/PrimaryCare/Obesity/6480&quot; mce_href=&quot;http://www.medpagetoday.com/PrimaryCare/Obesity/6480&quot; target=&quot;_blank&quot;&gt;Missing Link Found: Bariatric Surgery Reduces Mortality&lt;/a&gt;)&lt;/p&gt;
&lt;p&gt;Schauer and colleagues obtained rates of inhospital mortality following bariatric surgery from the 2005 National Inpatient Survey, then multiplied them by three to estimate 30-day mortality.&lt;/p&gt;
&lt;p&gt;The researchers explained that according to earlier research, inhospital death rates typically underestimate 30-day mortality by a factor of two to three.&lt;/p&gt;
&lt;p&gt;Their threefold correction factor represents &quot;a conservative estimate that biases the model against gastric bypass surgery,&quot; they wrote.&lt;/p&gt;
&lt;p&gt;Schauer and colleagues tested this correction factor and other aspects of the model in sensitivity analyses.&lt;/p&gt;
&lt;p&gt;The biggest gains in life expectancy occurred in younger women with relatively high BMI values, the model showed.&lt;/p&gt;
&lt;p&gt;The age effect was less important than BMI at the time of surgery. A 35-year-old woman with BMI of 45 would gain about 3.2 years of extra life, whereas at 55, a similarly obese woman would gain about 2.5 extra years.&lt;/p&gt;
&lt;p&gt;But a 35-year-old woman with BMI of 55 could expect to live five more years with surgery, the model indicated.&lt;/p&gt;
&lt;p&gt;Men in general derived less survival benefit from bariatric surgery, particularly with advancing age at the time of the procedure.&lt;/p&gt;
&lt;p&gt;At 35, the difference in life expectancy gained was roughly 10%, but by age 75 it had grown to about 50%.&lt;/p&gt;
&lt;p&gt;The sensitivity analyses found that relatively large changes in most parameters used in the model did not affect the overall results substantially.&lt;/p&gt;
&lt;p&gt;The effect of 30-day mortality on whether or not surgery was beneficial for long-term survival was related to BMI and gender.&lt;/p&gt;
&lt;p&gt;For women with a BMI of 40, 30-day mortality of more than 5% would mean surgery was not helpful, but short-term mortality had to exceed 15% for surgery not to be preferable for those with BMI of 55 or more. These thresholds were about 10% higher for men.&lt;/p&gt;
&lt;p&gt;The efficacy of surgery in reducing mortality was less important for older men, the analysis also showed. A 75-year-man with a BMI of 35 could expect only a very slight gain in life span  --  perhaps one or two months.&lt;/p&gt;
&lt;p&gt;&quot;Younger patients have lower surgical risk and more time over which to realize the benefits of surgery. For older patients, the gain is smaller, and for some, gastric bypass surgery will decrease life expectancy,&quot; Schauer and colleagues wrote.&lt;/p&gt;
&lt;p&gt;However, they identified several potentially serious limitations to the analysis.&lt;/p&gt;
&lt;p&gt;The study of long-term mortality following bariatric surgery was conducted at a single center and was not randomized. Additionally, long-term complications, such as need for repeat surgery, were not addressed in the model. Certain other risks that might be heightened after bariatric surgery were excluded as well, and quality of life was not modeled.&lt;/p&gt;
&lt;p&gt;&quot;The decision analysis presented here is a step forward in understanding optimal patient selection but also highlights some of the areas for which better data are needed,&quot; the researchers wrote.&lt;/p&gt;
&lt;div style=&quot;float:left;border-style:solid;border-width:1px;border-color:#8dabbc;font-family:arial;font-size:12px;background-color:#DBE9F2;padding:5px;&quot;&gt;&lt;p&gt;The National Institute of Diabetes and Digestive and Kidney Diseases funded the study.&lt;/p&gt;&lt;p&gt;No potential conflicts of interest were reported.&lt;/p&gt;&lt;/div&gt;&lt;div style=&quot;clear:both;&quot;&gt;&lt;/div&gt;
    </recommendedItem>
    <recommendedItem id="20090101_1_514"
                     title="AASLD: Lighter Patients with Liver Cancer Fare Better"
                     score="-0.006"
                     href="