Long-Acting Contraceptives 20 Times More Effective Than the Pill, Patch, and Ring .

Long-acting contraceptives are 20 times more effective than shorter-acting methods, according to a New England Journal of Medicine study.

Nearly 7500 U.S. women at risk for unintended pregnancy were counseled about various reversible contraceptive methods, with a special emphasis on the lower failure rates with the two long-acting reversible methods: intrauterine devices and subdermal implants. The women were then allowed to choose any contraceptive method to use at no cost for up to 3 years.

Overall, there were 334 unintended pregnancies. In age-adjusted analyses, pregnancy risk was significantly higher among women using birth control pills, the patch, or the ring than among those using IUDs or implants (hazard ratio, 21.8). Participants under age 21 who used short-acting contraceptives had nearly twice the pregnancy risk as older participants using the same methods, while risk did not differ between age groups for long-acting contraceptives.

Dr. Eleanor Bimla Schwarz of Journal Watch Women’s Health commented: “These findings highlight the need to ensure that young women are informed about and have access to IUDs and contraceptive implants.”

Source: NEJM



Aspirin Prevents Recurrent Unprovoked Venous Thromboembolism.

Aspirin is probably less effective –– but safer –– than warfarin.

Patients with unprovoked venous thromboembolism (VTE) face a dilemma: Recurrent VTE is common after warfarin anticoagulation is stopped, but the cumulative incidence of serious bleeding is high when patients continue warfarin therapy indefinitely. This difficult tradeoff provides an impetus to see whether aspirin is a suitable alternative for such patients.

Italian researchers identified 403 patients with a first symptomatic VTE event that was unprovoked (i.e., not associated with standard VTE risk factors); 63% had proximal deep venous thrombosis, and 37% had pulmonary embolism. After 6 to 18 months of treatment with a vitamin K antagonist, patients were randomized to either aspirin (100 mg daily) or placebo for 2 years.

The incidence of recurrent VTE was significantly lower in the aspirin group than in the placebo group (6.6% vs. 11.2% annually; P=0.02). The frequency of bleeding events was identical in the two groups (1 major bleed and 3 nonmajor bleeds). Aspirin afforded protection both to patients whose index event was deep venous thrombosis and to those whose index event was pulmonary embolism.

Comment: For patients with unprovoked VTE, this trial provides persuasive evidence that aspirin reduces the incidence of recurrent events after conventional warfarin therapy. Aspirin is less effective than warfarin, but bleeding risks are lower with aspirin. Newer oral anticoagulants (e.g., dabigatran and rivaroxaban) have also been studied as extended maintenance therapies for patients with VTE, but are not yet FDA-approved for this purpose.

Source: Journal Watch General Medicine


The Economic Burden of Dengue in Puerto Rico

Households incurred 48% of the cost of dengue illness, the government 24%, insurance 22%, and employers 7%.

Dengue incidence is increasing globally — but at what cost, and to whom?

In a recent, vaccine manufacturer–supported study, researchers used surveillance data, patient interviews, medical records, and financial data from patients, health facilities, and insurance companies to estimate the annual average aggregate costs of treated dengue cases in Puerto Rico from 2002 through 2010. Cost per case — used to project aggregate cost — was determined through detailed assessment of 100 patients with laboratory-confirmed dengue, of whom 67 were hospitalized and 44 were aged <15 years.

During the study period, >60,000 suspected dengue cases were reported; >22,000 of these cases were confirmed. The average annual aggregate cost of treated cases was $38.7 million ($10.40 per capita); adults accounted for 70% of these costs, and hospitalized patients for 63%. Households incurred 48% of such cost, the government 24%, insurance 22%, and employers 7%. When the cost of surveillance and control programs were added to the cost of dengue illness, the aggregate cost rose to $46.4 million ($12.47 per capita). Work absenteeism per episode exceeded that shown for influenza in the U.S. and other industrialized countries.

Comment: As noted by the authors and an editorialist, the economic burden of dengue has been poorly defined and generally underestimated. In Puerto Rico, households funded almost half the cost of illness. The cost of dengue illness there was roughly five times the cost of surveillance and vector-control programs, leading the authors to suggest that increases in the latter would pay off economically. This analysis is useful for planners considering investments in interventions, including vaccines, but because of regional differences in dengue epidemiology, costs will vary by geographic region.

Source: Journal Watch Infectious Diseases


Does Appropriateness of PCI Influence Procedural Outcomes?

An analysis of registry data reveals no such association, suggesting that patient selection and procedural performance should be assessed separately.

Appropriate use criteria (AUC) for percutaneous coronary intervention (PCI) have become a major quality metric for patient selection and resource utilization. In this analysis, investigators made use of the National Cardiovascular Data Registry to determine whether an association exists between adherence to AUC and in-hospital outcomes of PCI.

Included were 203,561 patients undergoing PCI for nonacute indications at 779 hospitals during 2009–2011. A total of 12.1% of the procedures were classified as inappropriate (range, 0%–56.6%). Compared with the hospital tertile with the lowest median rate of inappropriate PCI (5.3%), the tertile with the highest rate (20.0%) had similar risk-adjusted in-hospital mortality (0.3%; odds ratio, 1.12; P=0.35) and periprocedural bleeding rate (1.7%; OR, 1.02; P=0.07), as well as a similar rate of guideline-recommended medications provision at discharge (85.2%; P=0.58).

Comment: These investigators failed to find an association between inappropriate percutaneous coronary intervention and in-hospital outcomes, suggesting that patient selection for PCI by appropriate use criteria represents an aspect of PCI quality that differs from processes of care assessed by other metrics, including postprocedure outcomes. The wide range of variation in PCI appropriateness among hospitals is cause for concern, but these findings indicate that AUC adherence alone is an insufficient measure of the quality of PCI at any given hospital.

Source: Journal Watch Cardiology

Sensing the infrared: Researchers improve infrared detectors using single-walled carbon nanotubes

Whether used in telescopes or optoelectronic communications, infrared detectors must be continuously cooled to avoid being overwhelmed by stray thermal radiation. Now, a team of researchers from Peking University, the Chinese Academy of Sciences, and Duke University (USA) is harnessing the remarkable properties of single-walled carbon nanotubes (SWNTs) to create highly sensitive, “uncooled” photovoltaic infrared detectors.

This new type of detector, which the team describes in a paper published today in the Optical Society’s (OSA) open-access journal Optical Materials Express, may prove useful for industrial, military, manufacturing, optical communications, and scientific applications.

Carbon nanotubes are known for their outstanding mechanical, electrical, and optical properties. “They also are an ideal nanomaterial for infrared applications,” says Sheng Wang, an associate professor in the Department of Electronics at Peking University in Beijing, China, and an author of the Optical Materials Express paper. “For starters, these nanotubes exhibit strong and broadband infrared light absorption, which can be tuned by selecting nanotubes of different diameters. Also, due to their high electron mobility, nanotubes react very rapidly – on the order of picoseconds – to infrared light.” In comparison to traditional infrared detectors, which are based on semiconductors made of a mercury-cadmium-telluride alloy, the SWNTs are an order of magnitude more efficient, the researchers report.

The team’s photovoltaic infrared detector is formed by aligning SWNT arrays on a silicon substrate. The nanotubes arrays are then placed between asymmetric palladium and scandium contacts. These two metals have properties that collectively create what is known as an Ohmic contact, a region in a semiconductor device that has very low electrical resistance, which helps make the detector operate more efficiently.

“Fabrication of carbon nanotube infrared detectors can be readily implemented on a flexible substrate and large wafer at a low cost,” explains Wang.

The detector demonstrated “acceptable sensitivity” at room temperature and may be significantly improved by increasing the density of the carbon nanotubes, according to the team. The signal-to-noise performance of conventional infrared photodetectors is limited by their natural infrared emission, which is subsequently absorbed by the detector. To avoid having this stray radiation overwhelm the detector, liquid nitrogen or electric cooling is generally used to suppress this thermal effect. However, this makes infrared detectors more complex and expensive to operate. The new design eliminates this need because carbon nanotubes have special thermal properties. At room temperature, they emit comparatively little infrared radiation of their own, especially when the carbon nanotube is on the substrate. In addition, nanotubes are very good at conducting heat, so temperatures do not build up on the detector itself.

One of the biggest surprises for the team was achieving relatively high infrared detectivity (the radiation power required to produce a signal from a photoconductor) using a carbon nanotube thin film only a few nanometers thick, Wang points out. Notably, conventional infrared detectors require much thicker films, on the scale of hundreds of nanometers, to obtain comparable detectivity.

Another huge advantage of the detector is that the fabrication process is completely compatible with carbon nanotube transistors – meaning no big expensive equipment changes are necessary. “Our doping-free chemical approach provides an ideal platform for carbon nanotube electronic and optoelectronic integrated circuits,” says Wang.

The next step for the team is to focus on improving the detectivity of the detector with greater SWNT density, and to also achieve a wide spectrum response with improved diameter control.

More information: The paper, “Carbon Nanotube Arrays Based High-Performance Infrared Photodetector,” by Q. Zeng et al. will appear in a special feature issue on “Nanocarbon for Photonics and Optoelectronics” in Vol. 2, Issue 6 of Optical Materials Express.

Journal reference: Optical Materials Express

Source: Optical Society of America


Carl Sagan on Mastering the Vital Balance of Skepticism & Openness.

Fine-tuning the machinery of distinguishing the valid from the non-valid.

Seven years ago this week, David Foster Wallace argued that “learning how to think really means learning how to exercise some control over how and what you think.” Yet in an age of ceaseless sensationalism, pseudoscience, and a relentless race for shortcuts, quick answers, and silver bullets, knowing what to think seems increasingly challenging. We come up with tools like The Baloney Detection Kit and create wonderful animations to teach kids about critical thinking, but the art of thinking critically is a habit that requires careful and consistent cultivation. In his remarkable essay titled “The Burden of Skepticism,” originally published in the Fall 1987 issue of Skeptical Inquirer, Carl Sagan — always the articulate and passionate explainer — captured the duality and osmotic balance of critical thinking beautifully:

It seems to me what is called for is an exquisite balance between two conflicting needs: the most skeptical scrutiny of all hypotheses that are served up to us and at the same time a great openness to new ideas. Obviously those two modes of thought are in some tension. But if you are able to exercise only one of these modes, whichever one it is, you’re in deep trouble.

If you are only skeptical, then no new ideas make it through to you. You never learn anything new. You become a crotchety old person convinced that nonsense is ruling the world. (There is, of course, much data to support you.) But every now and then, maybe once in a hundred cases, a new idea turns out to be on the mark, valid and wonderful. If you are too much in the habit of being skeptical about everything, you are going to miss or resent it, and either way you will be standing in the way of understanding and progress.

On the other hand, if you are open to the point of gullibility and have not an ounce of skeptical sense in you, then you cannot distinguish the useful as from the worthless ones. If all ideas have equal validity then you are lost, because then, it seems to me, no ideas have any validity at all.

Some ideas are better than others. The machinery for distinguishing them is an essential tool in dealing with the world and especially in dealing with the future. And it is precisely the mix of these two modes of thought that is central to the success of science.

Source: http://www.brainpickings.org/

Chi-Huey Wong Awarded Nikkei Asia Prize.

Chi-Huey Wong, Scripps Research Institute Ernest W. Hahn Professor of Chemistry, has been awarded the Nikkei Asia Prize for science, technology, and innovation.

Wong, who also serves as president of Academia Sinica in Taiwan, was cited for his research in glycochemistry, “which has opened the way for the development of vaccines and medicines, especially in areas related to cancer, infectious, and immunological diseases,” according to the award announcement.

Launched by Nikkei Inc., a Japan-based global media corporation, the Nikkei Asia Prize recognizes achievements of individuals or organizations in Asia that have improved peoples’ lives in that world region. The awards program recognizes significant contributions in three areas: regional growth; science, technology and innovation; and culture.

Raspberry Pi to add camera later this year.

The Raspberry Pi, a uniquely priced, no casing computer that plugs into your TV and a keyboard., will be given a camera accessory later this year. That may be “oh-so-what” news if this were a mainstream machine but the Raspberry Pi is quite something else. This is a Model-A, Model-B $25 to $35 credit-card sized PC that grew out of The Raspberry Pi project, a UK based foundation. When the computer was made available in March, the device’s first batch sold out in hours after sites distributing the product witnessed unprecedented traffic.

The device is designed as a means of helping young people learn about computers beyond uploading pics and downloading documents. The developers created a computer that includes a 700 MHz processor, 256 MB RAM and the capability of playing games, doing spreadsheets, word processing and playing high definition video. (Model A has been redesigned to have 256 Mb RAM, one USB port and no Ethernet. Model B has 256Mb RAM, two USB ports and an Ethernet port.) Now a camera is on its way.Information so far is that the team has been working with a 14-megapixel camera but because user cost, not panache, is paramount, the camera of final choice may be scaled back.

Price was a key consideration in the early days of coming up with the Raspberry Pi, as the team behind the computer spent much time hunting down components that would achieve for them the best balance between cost and quality. (One question that is sometimes asked is why if the foundation is UK-based does it present its prices in US dollars. The team buys components that are priced in dollars and they negotiate manufacturing in dollars.)

The camera type will also need to keep in line with affordability considering their target user base.“We don’t have a price for the camera module yet; we’ll need to finalize exactly what hardware is in it first, but we will, of course, be ensuring that it’s very affordable,” according to site comments about the camera on its way.

The Raspberry Pi team sees the camera as a further extension of their education aims, for those who may be interested in robotics and building home-automation apps.

While design plans are not finalized, what is known is that the camera will attach to the Raspberry Pi with ribbon cable. According to the site, the module will be released for sale later this year, “hopefully before the end of the summer.”

The team also plans on selling cases by the summer; buyers will be able to choose a unit with or without a case or a case on its own,

Source: Physics.Org

Pasireotide effective in patients with active acromegaly.

Patients with acromegaly who took pasireotide long-acting release were 63% more likely to obtain biochemical control than those who took ocreotide long-acting release, according to data presented at the 2012 Joint 15th International Congress of Endocrinology and 14th European Congress of Endocrinology Meeting.

Annamaria Colao, MD, researcher and professor of endocrinology, chief of the neuroendocrine unit in the Department of Molecular and Clinical Endocrinology and Oncology, Federico II University of Naples, and colleagues conducted a randomized, double-blind, phase 3 study to evaluate the efficacy and safety of pasireotide (SOM230, Novartis) LAR compared to octreotide (Sandostatin, Novartis) LAR (octreotide/IM injection) in patients with acromegaly.

The 12-month study included 358 patients with active acromegaly – a rare endocrine disorder marked by the enlargement of the hands, feet, internal organs and facial structure. Those patients were assigned to two types of treatment categories: intramuscular injections of pasireotide LAR 40 mg (n=176) or octreotide LAR 20 mg (n=182) every 28 days for 12 months.

“While Sandostatin LAR is an effective treatment, inadequate control of GH and IGF-1 remains an issue for many patients with acromegaly and new therapeutic approaches are needed for these patients to better control their disease,” Colao said. “We are very encouraged by the findings of this study, the largest ever in this population, which found that pasireotide LAR provided full control in nearly a third of study participants.”

The study was completed by 80.1% (141/176) of patients taking pasireotide LAR and 85.7% (156/182) of patients taking octreotide LAR, with dose increases in 50.6% patients on pasireotide LAR and 67.6% on octreotide LAR.

Researchers said the primary endpoint was met when more patients treated with pasireotide LAR (31.3%) accomplished full control of acromegaly, compared with those taking octreotide LAR (19.2%; P=0.007).

By month 3, mean GH and IGF-1 decreased and remained surpressed. In addition to these findings, researchers found both treatments were beneficial in reducing GH levels and tumor volume, as well as improving quality of life and signs or symptoms associated with acromegaly.

Despite a higher prevalence of hyperglycemia, researchers concluded that the safety of pasireotide LAR was similar to that of octreotide LAR.

Patients who did not acquire full control during the 12-month study could switch to the other treatment in a 6-month extension study. After the extension, 21% of the 81 patients who switched to pasireotide LAR gained full control of the disease, whereas just 2.6% of 38 patients who switched to octreotide LAR achieved the same results.

Source: Endocrine today.





Regulating testosterone in elderly men yielded weight loss, improved BP.

By raising serum testosterone to normal levels, progressive weight loss, waist circumference and improved metabolic profile were evident among patients in a cumulative prospective study, according to data presented at the 19th European Congress on Obesity Meeting in Lyon, France.

“Raising serum testosterone to normal reduced body weight, waist circumference, and blood pressure, and improved metabolic profiles. These improvements were progressive over the full 5 years of the study,” the researchers said.

With an understanding that obesity is associated with reduced testosterone, and low testosterone induces weight gain, Farid Saad, MD, of Medical Affairs Men’s Health Care at Bayer Pharma AG in Berlin, and colleagues analyzed the effects of normalizing serum testosterone in mainly elderly (aged 38 to 83 years) hypogonadal men (n=251).

For at least 2 years, 214 men were studied, and 115 were studied for at least 5 years, with a mean age of 61 years.

The patients’ baseline testosterone levels were 0.14 ng/mL to 3.5 ng/mL (with a cutoff for testosterone treatment of ≤3.5 ng/mL), and they were assigned parenteral testosterone undecanoate 1,000 mg during the course of the study. Injections were given at baseline, after 6 weeks and every 12 weeks thereafter.

Of the 115 men studied for 5 years, 16 kg was the average weight loss, and mean weight of the group decreased from 106 kg to 90 kg. Additionally, men lost an average of 3.5 inches of their waist circumference (42 inches to 38.5 inches), and the average BMI decreased from 34 to 29, dramatically decreasing the average BMI of the patients from obese (>30) to overweight (25-30).

The results of the study improved the overall metabolic profile, with LDL cholesterol lowered from 163 mg/dL to 109 mg/dL, triglycerides from 276 mg/dL to 189 mg/dL, and average blood glucose measurements from 103 mg/dL to 94 mg/dL. Systolic BP decreased from 153 mm Hg to 137 mm Hg and diastolic BP from 93 mm Hg to 79 mm Hg.

An increase in energy and motivation were also apparent among patients participating in the study.

Source: Endocrine today.