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Selman Abraham Waksman, an Russian bacteriologist, together with H. Boyd Woodruff had devised a growth inhibition zone technique for identifying natural substances with antibacterial properties, specifically targeted for pathogenic bacteria. Dr. Waksman identified actinomycin, the first true antibiotic that had both bacteriostatic and bactericidal properties from the microbe Actinomyces antibioticus. He identified more than 20 new natural inhibitory substances, including streptomycin and neomycin, and proposed the now standard term “antibiotics” for this class of natural growth inhibitors. During his lifetime, Waksman received some 66 awards and 22 honorary degrees, however, Waksman's greatest honor came when he won the Nobel Prize in physiology or medicine in 1952 “for his discovery of streptomycin, the first antibiotic effective against tuberculosis.” This distinction earned him the title of “Father of Antibiotics”.

Cells can fight viruses, even when stimulated to combat bacteria

In a new study, published in Science, Gewirtz and his colleagues tested whether an injection of flagellin, a protein that’s part of the flagella of some bacteria, activates the body’s antibacterial defenses. They found out that it did, enabling mice to subsequently survive what should have been a lethal dose of harmful intestinal bacteria. The surprise came when Gewirtz’s team infected the mice with rotavirus, a common cause of severe diarrhea in young children. Even though the virus doesn’t have a flagellum, injecting the rodents with flagellin in advance protected them against the pathogen.

The researchers went on to figure out why. It turns out when the cells detect flagellin, they spur other cells to emit interleukin-22 (IL-22) and interleukin-18 (IL-18), molecular signals that help orchestrate a defensive response. IL-22 makes intestinal cells more resistant to viral invasion, whereas IL-18 thwarts the virus by spurring cells it has already infected to commit suicide. So when these molecules are activated, they fight bacteria as well as rotavirus.

The crossover protection the authors observed is unexpected. “We think the system we’ve developed will be broadly applicable to other viral infections,” Gewirtz says. He and his colleagues are now testing whether the combination (of IL-22 and IL-18) allows mice to resist a range of viruses, including norovirus, a gastrointestinal pathogen notorious for causing outbreaks on cruise ships.

Rotaviruses like these might be vulnerable to our antibacterial defenses.

Source: news.sciencemag.org

First successful delivery of dialysis in Ebola virus disease provided

Acute kidney injury occurs frequently in Ebola virus disease; however, providing hemodialysis to affected patients was previously thought to be too risky because it involves large needles or catheters and potential contact with highly infectious blood. Clinicians recently accomplished the first known successful delivery of renal replacement therapy with subsequent recovery of kidney function in a patient with Ebola virus disease. Their protocol will be presented at ASN Kidney Week 2014 at the Pennsylvania Convention Center in Philadelphia, PA. It will also appear in an upcoming issue of the Journal of the American Society of Nephrology (JASN).

The report by Michael Connor, Jr, MD, Harold Franch, MD (Emory University School of Medicine), and their colleagues details the measures the clinicians took to maximize safety and minimize risk of secondary transmission of Ebola virus, including careful considerations to the types of equipment used and the protocols that clinical staff followed. None of the staff developed Ebola virus disease after a 21-day observation period, and no detectable Ebola virus genetic material was found in the patient's dialysis waste fluids.

"In our opinion, this report confirms that with adequate training, preparation, and adherence to safety protocols, renal replacement therapies can be provided safely and should be considered a viable option to provide advanced supportive care in patients with Ebola" said Dr. Connor.

In light of their success, the team has proposed a set of clinical practice guidelines for acute renal replacement therapy in Ebola virus disease.

"More than anything else, in our report, we found that extra training of our volunteer ICU nurses made success possible. We thank them for their bravery and commitment." said Dr. Franch. "Our case also shows that dialysis is not a death sentence for patients suffering from Ebola virus disease and recovery of kidney function is possible."

Source: www.sciencedaily.com