Survival of Selected Viruses on Processed Pork Products

Contamination of food with viruses of human health significance is primarily due to human carriers. While cooking or fermenting and drying will inactivate viruses, products can be contaminated post-processing. The data show that the changes produced in pork products by processing will have little effect in decreasing viral numbers if post-processing contamination occurs

Left versus right subcallosal cingulate deep brain stimulation for treatment-resistant depression

Deep brain stimulation (DBS) of the subcallosal cingulate has emerged as a promising therapy for treatment-resistant depression (TRD). To date, all studies have employed bilateral stimulation; however, the physiology of affect and pathophysiology of depression are known to be asymmetric across hemispheres. Unilateral stimulation may provide efficacy while decreasing risk. Five patients were exposed to unilateral open-label DBS to the subcallosal cingulate for 12 weeks each to the left and then right hemispheres in a double-blind, crossover fashion. After 12 weeks of stimulation to each hemisphere, bilateral stimulation was initiated, and patients were followed for 12 additional weeks. Additionally, nine months of long-term follow up data were collected. Left, but not right, unilateral stimulation was associated with significant decrease in depression scores; with bilateral stimulation, all patients improved and one patient remitted. No serious adverse events were associated with surgery or acute or chronic stimulation. This small study suggests that unilateral DBS to the subcallosal cingulate may be an effective treatment for TRD. All patients improved with bilateral stimulation, though antidepressant effects following 12 weeks were modest. These findings contrast somewhat with prior open-label trials, though duration of bilateral stimulation was shorter in this trial. The current study continues to confirm safety of implantation and use of DBS to the subcallosal cingulate for patients with TRD and highlights the importance of personalization of therapy, for example by hemisphere, in future trials

The origin and maintenance of metabolic allometry in animals

Organisms vary widely in size, from microbes weighing 0.1 pg to trees weighing thousands of megagrams - a 10-fold range similar to the difference in mass between an elephant and the Earth. Mass has a pervasive influence on biological processes, but the effect is usually non-proportional; for example, a tenfold increase in mass is typically accompanied by just a four- to sevenfold increase in metabolic rate. Understanding the cause of allometric scaling has been a long-standing problem in biology. Here, we examine the evolution of metabolic allometry in animals by linking microevolutionary processes to macroevolutionary patterns. We show that the genetic correlation between mass and metabolic rate is strong and positive in insects, birds and mammals. We then use these data to simulate the macroevolution of mass and metabolic rate, and show that the interspecific relationship between these traits in animals is consistent with evolution under persistent multivariate selection on mass and metabolic rate over long periods of time

How long do nosocomial pathogens persist on inanimate surfaces? A systematic review

BACKGROUND: Inanimate surfaces have often been described as the source for outbreaks of nosocomial infections. The aim of this review is to summarize data on the persistence of different nosocomial pathogens on inanimate surfaces. METHODS: The literature was systematically reviewed in MedLine without language restrictions. In addition, cited articles in a report were assessed and standard textbooks on the topic were reviewed. All reports with experimental evidence on the duration of persistence of a nosocomial pathogen on any type of surface were included. RESULTS: Most gram-positive bacteria, such as Enterococcus spp. (including VRE), Staphylococcus aureus (including MRSA), or Streptococcus pyogenes, survive for months on dry surfaces. Many gram-negative species, such as Acinetobacter spp., Escherichia coli, Klebsiella spp., Pseudomonas aeruginosa, Serratia marcescens, or Shigella spp., can also survive for months. A few others, such as Bordetella pertussis, Haemophilus influenzae, Proteus vulgaris, or Vibrio cholerae, however, persist only for days. Mycobacteria, including Mycobacterium tuberculosis, and spore-forming bacteria, including Clostridium difficile, can also survive for months on surfaces. Candida albicans as the most important nosocomial fungal pathogen can survive up to 4 months on surfaces. Persistence of other yeasts, such as Torulopsis glabrata, was described to be similar (5 months) or shorter (Candida parapsilosis, 14 days). Most viruses from the respiratory tract, such as corona, coxsackie, influenza, SARS or rhino virus, can persist on surfaces for a few days. Viruses from the gastrointestinal tract, such as astrovirus, HAV, polio- or rota virus, persist for approximately 2 months. Blood-borne viruses, such as HBV or HIV, can persist for more than one week. Herpes viruses, such as CMV or HSV type 1 and 2, have been shown to persist from only a few hours up to 7 days. CONCLUSION: The most common nosocomial pathogens may well survive or persist on surfaces for months and can thereby be a continuous source of transmission if no regular preventive surface disinfection is performed