[Brazil school]12 children killed in Brazil school shooting

A gunman roamed the halls of an elementary school in Rio de Janeiro on Thursday and killed 12 children, lining them up against a wall and shooting them in the head at point-blank range as he shouted, ``I'm going to kill you all!''

   It was the worst school shooting in Brazil _ and would have been deadlier if the gunman had not been shot in the legs by a police officer, who said the man then fell down some stairs and shot himself in the head.

   Images taken with a cell phone and posted on YouTube showed students fleeing wildly, screaming for help, many with their white and blue school shirts soaked in blood.

   Rio de Janeiro state's Secretariat of Health and Civil Defense said in a statement on its website that at least 12 other students were injured, many by gunfire, and taken to hospitals. At least two were in grave condition. Officials earlier reported 18 injured.

   The dead included 10 girls and two boys, plus the gunman, according to the Health and Civil Defense department. Those killed were between the ages of 12 and 15. One of the boys died at a hospital about 12 hours after the shooting.

   ``He came in shooting,'' said Andreia Machado, recounting what her 13-year-old daughter, Thayane, told her before going into surgery.

   Thayane was hit by three bullets and lost feeling in her legs because one hit her spine, said her mother. Crying as she spoke, Machado wondered if her daughter would ever be able to return to school _ or walk.

   ``She's such an active child,'' she said. ``That's the biggest fear I have, her not being able to walk again. But we have to trust in God.''

   The gunman was identified as 23-year-old Wellington Oliveira, who had once attended the Tasso da Silveira school in a working-class neighborhood in western Rio.

   No motive was known, but authorities said the shooter left a rambling and mostly incoherent letter at the scene indicating he wanted to kill himself.

   The letter also explained in detail how Oliveira wanted his corpse to be cared for _ bathed and wrapped in a white sheet that he left in a bag in the first room where he said he would start shooting. The letter also states that the gunman should not be touched by anyone who is ``impure'' unless they wear gloves.

   ``If possible I want to be buried next to my mother. A follower of God must visit my grave at least once. He must pray before my grave and ask God to forgive me for what I have done,'' read the letter, portions of which were posted on the Globo television network's website.

   Edmar Peixoto, the deputy mayor of western Rio, said the letter also stated the gunman was infected with the AIDS virus.

   The public school was in the midst of celebrating its 40th anniversary, and students' handmade posters commemorating the day could be seen through school windows.

   Rio Police Chief Martha Rocha said that when Oliveira first entered the school he told staff members he was there to give a lecture.

   Shortly afterward, he opened fire. Rocha said he was carrying two pistols and an ammunition belt. He fired off at least 30 rounds.

   Rio is a city rife with drug-gang violence in its vast slums, but school shootings are rare. The gunman had no criminal history, Rocha told a news conference.

   About 400 people were inside the school when the shooting began about 8:30 a.m. local time (7:30 a.m. EDT, 1130 GMT). The school serves grades one through eight.

   ``What happened in Rio is without a doubt the worst incident of its kind to have taken place in Brazil,'' said Guaracy Mingardi, a crime and public safety expert at the University of Sao Paulo.

   Jade Ramos, a student at the school, said the gunman repeatedly yelled ``I'm going to kill you all!''

   ``He had already killed a lot of children in the first floor and in the yard,'' she told the Globo television network. ``He kept telling the kids to face the wall and was shooting at their heads.

The children kept begging, 'No, please!' There was a lot of blood, children agonizing on the stairs.''

   Ramos said she escaped by running into a classroom, where a teacher then locked the door and barricaded it with tables.

   Police were alerted to the shooting when two young boys, at least one with a gunshot wound, ran up to two officers on patrol about two blocks away. The officers sprinted to the school and at least one quickly located the gunman on the second floor and traded shots with him.

   ``He saw me and aimed a gun at me,'' said officer Marcio Alves.

``I shot him in the legs, he fell down the stairs and then shot himself in the head.''

   Rio Mayor Eduardo Paes said life at the four-story, pastel yellow and green school was turned into a ``hellish nightmare.''

   ``This day would have been so much worse if it weren't for the hero policeman,'' Paes told reporters at the school.

   Authorities closed the school temporarily while they investigate, but Paes said it would reopen.

   Rio Gov. Sergio Cabral called the shooter a ``psychopath'' and said there were no indications anyone else was involved in the shooting, but that the investigation would continue.

   ``We have to investigate where he got the weapons and where he learned to use them,'' the governor said.

   Terrified parents rushed to the school in the Realengo neighborhood. Television images showed them crying and screaming for information about their children.

   Zilda Nunes, 67, lives across the street from the school and said three of her grandchildren were inside when the shooting began.

   She screamed for help when she heard the gunfire, but didn't enter the building. As students fled, she offered them sugar water to help calm them down, she said.

   ``There were so many children shot, so much blood,'' Nunes said.

``People were asking for help, but what could I do?''

   Three helicopters were landing and taking off from a football field next to the school, ferrying the wounded to hospitals.

   Brazilian President Dilma Rousseff, attending an event in the capital, Brasilia, lamented the deaths of ``defenseless children.''

   ``I ask for one minute of silence for these children who were taken so early from their life,'' she said, her voice cracking and eyes welling with tears. ``It's not in the nature of our nation to have these types of crimes.''

A policeman stands guard outside the Tasso da Silveira school in the western region of Rio de Janeiro, Brazil, April 7, 2011. A campus shooting here on Thursday morning killed 11 people and injured at least 22 others, the city's health chief, Sergio Cortes said.

A woman reacts outside a school after a shooting at the school in Rio de Janeiro, Brazil, Thursday April 7, 2011. Brazilian authorities say that a gunman opened fire in an elementary school in Rio de Janeiro and at least 13 people are dead, including the gunman.

Gene therapy raises hope for a future AIDS cure

In a bold new approach ultimately aimed at trying to cure AIDS, scientists used genetic engineering in six patients to develop blood cells that are resistant to HIV, the virus that causes the disease.

It's far too early to know if this scientific first will prove to be a cure, or even a new treatment. The research was only meant to show that, so far, it seems feasible and safe.

The concept was based on the astonishing case of an AIDS patient who seems to be cured after getting blood cells from a donor with natural immunity to HIV nearly four years ago in Berlin. Researchers are seeking a more practical way to achieve similar immunity using patients' own blood cells.

The results announced Monday at a conference in Boston left experts cautiously excited.

"For the first time, people are beginning to think about a cure" as a real possibility, said Dr. John Zaia, head of the government panel that oversees gene therapy experiments. Even if the new approach doesn't get rid of HIV completely, it may repair patients' immune systems enough that they can control the virus and not need AIDS medicines — "what is called a functional cure," he said.

Carl Dieffenbach, AIDS chief at the National Institute of Allergy and Infectious Diseases, agreed.

"We're hopeful that this is sufficient to give the level of immune reconstitution similar to what was seen with the patient from Germany," he said.

This is the first time researchers have permanently deleted a human gene and infused the altered cells back into patients. Other gene therapy attempts tried to add a gene or muffle the activity of one, and have not worked against HIV.

The virus can damage the immune system for years before people develop symptoms and are said to have AIDS — acquired immune deficiency syndrome. The virus targets special immune system soldiers called T-cells. It usually enters these cells through a protein receptor, or "docking station," called CCR5.

Some people (about 1 percent of whites; fewer of minorities) lack both copies of the CCR5 gene and are naturally resistant to HIV. One such person donated blood stem cells in 2007 to an American man living in Berlin who had leukemia and HIV.

The cell transplant appears to have cured both problems, but finding such donors for everyone with HIV is impossible, and transplants are medically risky.

So scientists wondered: Could a patient's own cells be used to knock out the CCR5 gene and create resistance to HIV?

A California biotechnology company, Sangamo (SANG-uh-moh) BioSciences Inc., makes a treatment that can cut DNA at precise locations and permanently "edit out" a gene.

Dr. Jacob Lalezari, director of Quest Clinical Research of San Francisco, led the first test of this with the company and colleagues at the University of California in San Francisco and Los Angeles.

He warned that it would be "way overstated" to suggest that the results so far are a possible cure.

"It's an overreach of the data. There are a lot of people out there with hopes and dreams around the C-word," so caution is needed.

In the study, six men with HIV had their blood filtered to remove a small percentage of their T-cells. The gene-snipping compound was added in the lab, and about one-fourth of the cells were successfully modified. The cells were mixed with growth factors to make them multiply and then infused back into the patients.

Three men received about 2.5 billion modified cells. Three others received about 5 billion.

Three months later, five men had three times the number of modified cells expected. As much as 6 percent of their total T-cells appear to be the new type — resistant to HIV, Lalezari said.

The sixth man also had modified cells, but fewer than expected. In all six patients, the anti-HIV cells were thriving nearly a year after infusion, even in tissues that can hide HIV when it can't be detected in blood.

"The cells are engrafting — they're staying in the bloodstream, they're expanding over time," said Lalezari, who has no personal financial ties to Sangamo, the study's sponsor.

The only side effect was two days of flulike symptoms. It will take longer to determine safety, but several AIDS experts said they were encouraged so far.

"It is a huge step" and a first for the field of genetics, said John Rossi, a researcher at City of Hope in Duarte, Calif., where he and Zaia plan another study to test Sangamo's approach. "The idea is if you take away cells the virus can infect, you can cure the disease."

On Wednesday, Dr. Carl June, a gene therapy expert at the University of Pennsylvania, will report partial results from a second, federally funded study of 10 people testing Sangamo's product. He treated his first patient with it in July 2009.

Many questions remain:

• People born without the CCR5 gene are generally healthy, but will deleting it have unforeseen consequences?

• Will HIV find another way into cells? Certain types of the virus can use a second protein receptor, though this is less common and usually when AIDS is advanced. Sangamo is testing a similar approach aimed at that protein, too.

• How long will the modified cells last? Will more be needed every few years?

• Could doctors just infuse Sangamo's product rather than removing cells and modifying them in the lab?

• What might this cost?

Sangamo spokeswoman Liz Wolffe said it's too early in testing to guess, but it would be "a premier-priced" therapy — in the neighborhood of Dendreon Corp.'s new prostate cancer immune therapy, Provenge — $93,000.

Yet AIDS drugs can cost $25,000 a year, so this could still be cost-effective, especially if it's a cure.

Jay Johnson, 50, who works for Action AIDS, an advocacy and service organization in Philadelphia, had the treatment there in September.

"My results are excellent," he said. "The overall goal is to not have to take medication, and then hopefully lead maybe to a cure."

Matt Sharp, 54, of suburban San Francisco, also had the treatment in September.

"I would trade anything to not have to take a handful of medications every day for the rest of my life and suffer all the consequences and side effects," he said.

"I may not live long enough to see the cure, but I always hoped for a chance."