Preventing Infection: Vaccine protects against malaria in early test

An experimental vaccine against malaria has tested well in early research. The Anopheles mosquito, shown here, spreads the parasite causing malaria.

The long, bumpy path to a malaria vaccine may have hit a smooth stretch as an early-stage study finds that multiple injections with inactivated malaria parasites can protect against the disease.

The findings are tantalizing but preliminary. The study was small, and the vaccine required five intravenously delivered doses to work, which would be an obstacle for teams attempting mass vaccination in developing countries. Also, the shots were tested in adults, not children, who are the prime victims of malaria.

Still, the study offers decidedly good news, says Anthony Fauci, director of the National Institute of Allergy and Infectious Diseases in Bethesda, Md., which sponsored the research. “This is an important advance,” he says, noting that the vaccine induces an immune onslaught that kills the malaria parasite in its infective sporozoite stage. That means uninfected mosquitoes that bite a vaccinated person wouldn’t get infected, slowing the disease’s spread, he says.

In the study, researchers gave four or five shots to 15 volunteers over several months. The volunteers were then bitten repeatedly by malarial mosquitoes. A few weeks afterward, 12 showed no disease, including all six who got five doses, the researchers report August 8 in Science. A control group of unvaccinated volunteers got the disease and received treatment promptly.

Scientists already knew that weakened versions of malaria sporozoites could induce immunity in people. To turn the sporozoites into a vaccine, scientists need to irradiate infected mosquitoes, and use the weakened parasites to elicit an immune response in people. In the new study, scientists mastered the delicate task of attenuating the parasites just enough so that they don’t replicate and cause disease, but leaving them active enough to trigger an immune response that would kill any full-strength sporozoites introduced by subsequent mosquito bites. The researchers also effectively delivered the vaccine into volunteers — albeit with IV injections. In earlier tests, this vaccine failed to gin up adequate immunity when given by shots into the skin, which are easier to deliver.

“This is the first step towards success with this approach,” says Denise Doolan, a molecular immunologist at the Queensland Institute of Medical Research in Herston, Australia. “It has taken enormous dedication and perseverance to achieve this result, and [the researchers] should be congratulated.”

Study coauthor Robert Seder, a physician and immunologist at NIAID, says the research team plans to test the vaccine in more people and find out how long the protection lasts. A field trial is planned in Tanzania.

Doolan says simpler and fewer shots are needed for far-reaching vaccination campaigns. If such a vaccine can be developed, she says, it should “have a dramatic impact on public health.”

Meanwhile, Seder says, the IV vaccine — if fully tested and approved — might be useful for protecting health officials, military forces and travelers. Fauci cautions that while this vaccine showed effectiveness against one strain of Plasmodium falciparum, the parasite that causes the most severe kind of malaria, the vaccine will have to prove itself against other strains.

Decoding Cancer:HeLa genome offers clues to cells’ cancerous nature

A detailed DNA profile of the world’s most widely used cancer cell line sheds light on the genetic chaos the cells use to grow virtually unchecked in laboratory cultures. That property may also explain their virulent growth in the woman who unwittingly left them to science.

The famous cells came from a biopsy taken in 1951, when Henrietta Lacks was dying from cervical cancer at Johns Hopkins Hospital. Although no one asked Lacks or her family for permission to perform experiments with the cells, they formed the first immortal human cell line ever successfully grown in the lab. HeLa cells were pivotal in developing a vaccine for polio, among other scientific milestones.

But one problem for researchers using HeLa cells has been that their genome is a scrambled version of a normal human genome. This makes it more difficult to design and interpret experiments using the cells.

The new work, reported by University of Washington researchers in the Aug. 8 Nature, will help scientists make better use of HeLa cells by providing information on the arrangement of genetic variants on chromosomes.

These details were “long overdue,” says Peter Park, a computational biologist at Harvard Medical School. “We no longer have to make assumptions about what the HeLa genome looks like.”

Human cells normally have two copies of each chromosome. Sometimes, a genetic variant differs between the two copies. But standard sequencing methods mix the data together, so it’s impossible to figure out which variant is on which chromosome. The University of Washington group overcame that obstacle by using a method that identifies which variants sit together on the same chromosome.

This new level of detail helps reconstruct an event that is thought to have contributed to Lacks’ cells becoming cancerous. Scientists already knew that the HeLa genome contained human papillomavirus DNA, which comes from the genome-invading virus that causes nearly all cervical cancers. The virus DNA had embedded itself near MYC, a human gene that, when artificially switched on, can cause cells to become cancerous.

The new study found that in chromosomes with viral DNA, the MYC gene turned on. But in matching chromosomes without viral DNA, MYC was not active. That meant that the viral DNA probably turns the MYC gene on, but only within the same chromosome. The researchers also found that the viral DNA actually touched the MYC gene, suggesting it directly causes the different MYC activity on the chromosomes. This reveals one of the ways that the invading virus might have helped Lacks’ cancer cells to grow uncontrollably.

“It’s a really lovely piece of work,” says geneticist Daniel MacArthur of Massachusetts General Hospital. “It's a shame that the technical achievements of the authors may be overshadowed by the ethical challenges.”

The HeLa genome sequence was published for the first time in March, by a research group led by Lars Steinmetz at the European Molecular Biology Laboratory in Heidelberg, Germany. These data, published in G3: Genes, Genomes, Genetics, mapped out the many rearrangements and mutations that distinguish the HeLa genome from a healthy human genome.

The study sparked a controversy because the sequence was freely available and could potentially be used to infer some of the genetic variants carried by Lacks’ family. In response the team withdrew the HeLa sequences from the public database.

The National Institutes of Health has now negotiated an agreement with the Lacks family that restricts access to HeLa genome and requires future publications based on the data to acknowledge the contribution of Henrietta Lacks and her family. The new arrangement also has members of the Lacks family joining a board that oversees requests to use the data.

Meteoritul de pe Marte isi dezvaluie varsta (Mars meteorite reveals its age)

Folosind un instrument ce poate debloca secretelr sistemului solar, s-a descoperit o noua tehnica ce determina precis varsta meteoritilor., raporteaza oamenii de stiinta in revista Nature.

Oamenii de stiinta nu se inteleg i privinta estimarii varstelor meteoritilor pentru ca este greu sa distingi perioada in care rocile s-au format si perioada in care ele au fost arse dintr-un impact si au zburat prin spatiu spre Pamant.

Geologul de la UCLA Axel Schmitt si coleii sai au inceput prin examinarea structurii cristalelor minerale ale meteoritului, care variaza, in funcite de doua criterii. Cristalele se pot forma prin solidificare gradata intr-un flux de lava sau se formeaza rapid in urma caldurii si presiunii impactului. Apoi au determinat varsta cristalelo prin masurarea ratiei de uraniu ce trebuie dusa/condusa. Uraniul are doi izotopi, fiecare descompunandu-se in propiul  izotop conducator, oferind cercetatorilor multiple masuratori pe baza datarii radioactive ce verifica consistenta.

Echipa a analizat meteoritul martian si au gasit cristale mari, conectate, cu o varsta de cca 187 milioane de ani,  fapt ce sugereaza ca roca s-a format acum aprox.187 mil ani in urma unei eruptii vulcanice. 

Cercetatoriiau gasit cristale de zircon care s-au format intr-un  impact acum aprox. 22 milioane de ani.

Schmitt spune ca prin aplicarea tehnicii pe rocile de pe marte, pe luna, pe asteroizi sau chiar pe Pamant oamenii de stiinta pot afla mai multe despre timpul in care au erupt vulcanii in trecutul indepartat.

Providing a tool for unlocking secrets of the early solar system, a new technique accurately determines the age of meteorites, scientists report in the July 25 Nature.

Scientists disagree over estimates of meteorites’ ages because it’s hard to distinguish between when the rocks formed and when they got seared from an impact and flung into space toward Earth.

UCLA geochronologist Axel Schmitt and colleagues began by examining the structure of a meteorite’s mineral crystals, which differs depending on whether the crystals solidified gradually within a lava flow or rapidly after the intense heat and pressure of an impact. Then they determined the age of the crystals by measuring the ratio of uranium to lead. Uranium has two isotopes, each of which decays into its own lead isotope, providing researchers with multiple radioactive-dating measurements to cross-check for consistency.

The team analyzed the Martian meteorite Northwest Africa 5298 and found large, interlocking crystals about 187 million years old, which suggests that the rock formed during a volcanic eruption back then. The researchers also found zircon crystals that likely formed from an impact no more than 22 million years ago.

Schmitt says that by applying the technique to rocks from Mars, the moon, asteroids and even Earth, scientists can learn about when volcanoes erupted in the distant past.

Fractalii in arta (Fractals in art)

M-am gandit sa va mai ofer niste informatii interesante despre fractali :)
Tipare de fractali au fost descoperite în picturile artistului american Jackson Pollock. Deși picturile lui Pollock par a fi doar stropi haotici, analiza computerizată a descoperit tipare de fractali în opera sa.
Iata un exemplu:

Fractalii sunt de asemenea predominanți în arta și arhitectura africană. Casele circulare apar în cercuri de cercuri, casele dreptunghiulare în dreptunghiuri de dreptunghiuri și așa mai departe. Astfel de tipare se găsesc și în textile și sculpturile africane, precum și în părul împletit în codițe.

Exemple de formare a fractalilor (cu obiecte obisnuite)
Un fractal se formează când se despart două plăci de acril lipite. 

Ramificarea fractalilor are loc în cazul suprafeţei DVD-urilor iradiate într-un cuptor cu microunde.

Si: O magnificare a mulţimii phoenix.

I have some extra information about fractals :)
Patterns for fractals were dicovered in Jackson Pollok's paintings.Even if his paintings look like chaotic drops, computer analysis has found fractal patterns in his work.
Here's an example:

Decalcomania, a technique used by artists such as Max Ernst, can produce fractal-like patterns. It involves pressing paint between two surfaces and pulling them apart.
Fractals appear in african architecture. Circular houses appear in circles of circles, rectangular houses in rectangles of rectangles, and so on. Such scaling patterns can also be found in African textiles, sculpture, and even cornrow hairstyles.
 A fractal is formed when pulling apart two glue-covered acrylic sheets.

Fractal branching occurs for DVDs area irradiated in a microwave oven.

And a magnification of the crowd phoenix.

-Ioana

Lumina "sucita" transmite mai multa informatie (Twisted light transmits more data)

Un nou cablu din fibra optica care transmite mai multe raze de lumina simultan poate usura si  grabi drastic viteza informatiei transmise pe internet.

Andrew Weiner, un fizician de la Universitatea Purdue din West Lafayette, Indiana spune ca:" E ca si cum am avea mai multe fibre optice insa fara a avea cu adevarat mai multe"

Companiile de telecomunicatii folosesc lumina pentru a codifica si transmite informatia prin cablurile din fibra optica. In ultimele decenii, savantii au marit latimea de banda prin faptul ca au permis fasciculului de lumina sa transmita mai multa informatie, dar progresul lor va fi depasit in curand de vastele cantitati de informatie pe care oamenii le schimba intre ei. Folosind mai multe fibre ar fi costisitor. Siddharth Ramachandran, fizician de la Universitatea Boston spune ca: "Am ajuns la punctul unde comunitatea telecomunicatiilor a inceput sa intrebe ce altceva am putea face".

Solutia pe care a gasit-o impreuna cu echipa lui este sa trimita mai multe raze de lumina simultan intr-o singura fibra. Aceasta idee e aparut acum 40 de ani , dar nu este un lucru usor de facut deoarece fibrele traditionale permit razelor de lumina ce se misca in paralel sa se amestece incurcand 1s si 0s codate in fiecare fascicul.

Recent, cercetatorii au incercat sa imparta torsiunile in unele dintre fascicule pentru ca ele sa formeze o spirala impreuna cu fibra, in timp ce celelalte circula in linie dreapta, dar nici acest lucru nu a mers.

Abandonand ideea "amestecarii" luminii, cativa dintre cercetatori au creat algoritmi complecsi care descifreaza fasciculele amestecate la capatul cablului, dar algoritmii sunt lenti si nu sunt eficienti 100%.

Pe 28 Iunie, Ramachandran si echipa lui au raportat construirea unei fibre lungi de 1,1 km, care, pentru rima oara, permitea multiplelor fascicule sa ajunga la destinatie intacte. Fibrele lor de siliciu sunt narcotizate  cu alte materiale, fapt ce permite fasciculelor sa se miste la viteze usor diferite si le impiedica sa se amestece.

Folosind un instrument numit "modulator de lumina spatiala" pentru a rasuci fasciculele, cercetatorii au trimis 4 fascicule concomitent, trimitand informatie de mai multe de 1.6 trilioane de biti pe secunda, prin fibra lor facuta la comanda. Ei spera sa comprime mai multa informatie  in fiecare din fascicule folosind metode deja exploatate de industria telecomunicatiilor. Ramachandran a observat ca echipa sa si-a fabricat fibrele folosind metode standard, astfel ca, daca vor fi produse la scara industriala fibra nu ar trebui sa coste mai mult decat cele deja disponibile.

Ramachandran spune ca nu este sigur daca noua fibra va putea fi utilizata pentru a comunica informatia pe distante mari ,dar spera ca va imbunatati transmisia in zonele cu populatie densa. De asemenea va ajuta la vastele servere ale fermelor de informatie, unde mii de computere stocheaza  informatii pentru cmpanii ca Google si Facebook care necesita retele ferme si rapide pentru a schimba informatii.

A new fiber-optic cable that seamlessly shuttles multiple beams of light simultaneously could drastically speed data transfer over the Internet.

“It’s like having more fibers without actually laying more fibers,” says Andrew Weiner, a physicist at Purdue University in West Lafayette, Indiana.

Telecommunications companies use light to encode and send data through fiber-optic cables. Over the last few decades, scientists have increased bandwidth by enabling a single beam to carry more information, but their progress soon will be outpaced by the vast amounts of data people exchange. Laying more fibers would be expensive. “We’ve gotten to the point where the [telecom] community has been asking what else we can do,” says Siddharth Ramachandran, a physicist at Boston University.

The solution he and his team came up with was to dispatch multiple beams of light through a single fiber. The idea goes back nearly four decades, but it’s not an easy thing to do because traditional fibers allow light beams moving in parallel to interfere with each other, jumbling the 1s and 0s encoded in each beam.

Recently, scientists have tried imparting twists into some of the beams so that they spiral along the fiber while others travel in a straight line, but that hasn’t worked either. Resigned to this light mixing, some researchers have created complex algorithms that decipher the amalgamated beams at the end of the cable, but the algorithms are slow and not 100 percent effective.

In the June 28 Science, Ramachandran and his team report building a 1.1-kilometer-long fiber that, for the first time, allows multiple beams to reach their destination intact. Their silica fiber is doped in places with other materials, which cause the beams to move at slightly different speeds and prevent them from mixing with each other.

Using an instrument called a spatial light modulator to twist the beams, the researchers sent as many as four concurrent beams, transmitting data at speeds up to 1.6 trillion bits per second, through their custom fiber. They hope to squeeze more data into each of those beams using methods already exploited by the telecom industry. Ramachandran notes that the team manufactured its fiber at a commercial facility using standard methods, so if it were mass produced, the fiber should not cost much more than those now in use.

Ramachandran says he is unsure whether the new fiber will work for communicating data over long distances, but hopes that it will improve transmission in dense metropolitan areas. It could also help in vast data server farms, where thousands of computers that store data for companies like Google and Facebook require tight, fast networks to exchange information.

Nicole Cherry - Memories

Tipa asta are 14 ani si canta minunat. M-am gandit sa postez melodia pentru ca Romania ar trebui sa-si sustina adevaratele talente:)

Pe urmele unui nou virus (On the trail of a new virus)

O echipa de cercetatori a descoperit un nou virus respirator letal care raspandeste cu usurinta in salile de spital.

Virusul este numit sindromul respirator coronavisrus al Orientului Mijlociu sau MERS, ne aminteste epidemiologul Trish Pearl de la universitatea Johns Hopkins.  Ea spune ca " cazurile sunt straniu de similare". Ea impreuna cu alti doi colegi au investigat o o eruptie SARS in Toronto acum 10 ani. In aceasta primavara, eu au ajutat la descoperirea unei infectii in lant a MERS in Arabia Saudita.

Prin examinarea dosarelor medicale si atenta urmarire a locurilor in care au fost pacientii si angajatii spitalelor, echipa lui Pearl a descoperit ca  clinicile de dializa jucau un rol important in eruptie. O persoana, desemnat  pacientul C, a infectat alti sapte, dintre care sase au fost supusi la dializa in acelasi timp cu el, au declarat membrii echipei pentru New England Journal of Medicine. Pacientul C a fost infectat cu MERS de la pacientul A, aflat in camera de spital de langa camera acestuia. Pacientul A a transmis ,in total, altor trei pacienti infectia.

Odata ce o persoana a fost infectata,dupa calculele cercetatorilor, sunt necesare 5,2 zile pentru ca simomele sa apara si 7.6 zile pana ce virusul e transmis unei alte victime. MERS pare ca se extinde mai repede in infectie decat SARS si este de asemenea mai letal.

SARS a infectat 8,098 pers si a omorat 9,5 % din ei, adica 774 pers, intre noiembrie 2002 si iulie 2003.

Pana in prezent, MERS a infectat 64 pers, omorand 59% dintre ele, adica 38 pers. In eruptia din Arabia Saudita, 65% din 23 de persoane care au preluat virusul au murit. Cei mai multi erau in varsta, sau aveau alte probleme de sanatate.

A new, deadly respiratory virus spreads easily in hospital settings, a team of investigators has found.

The virus, called the Middle East respiratory syndrome coronavirus, or MERS, reminds Johns Hopkins University epidemiologist Trish Perl of SARS. “The cases are eerily similar,” she says. Perl and two colleagues investigated a SARS outbreak in Toronto 10 years ago. This spring, they helped unravel the chain of infection of a MERS outbreak  in Saudi Arabia.

By examining medical records and carefully tracking where patients and hospital personnel had been, Perl’s team discovered that dialysis clinics played an important role in the outbreak. One man, designated Patient C, infected seven others, six of whom had undergone dialysis at the same time he did, the team reports June 19 in the New England Journal of Medicine. Patient C caught MERS from patient A, who was staying in the hospital room next door. Patient A ended up transmitting the virus to three people in total.

Once a person has been infected, it takes an average of 5.2 days for symptoms to appear and 7.6 days for MERS to spread to the next victim, the researchers calculate. MERS seems to spread earlier in the infection than SARS did. It is also more deadly.

SARS infected 8,098 people and killed 9.5 percent of them, or 774 people, between November 2002 and July 2003. To date, MERS has infected 64 people worldwide, killing 38, or about 59 percent. In the Saudi outbreak, 65 percent of the 23 people confirmed to have caught the virus died; most were elderly and had other health problems.