Multiple Genetic Mutations Associated with Polymyxin Resistance in Acinetobacter baumannii

We studied polymyxin B resistance in 10 pairs of clinical Acinetobacter baumannii isolates, two of which had developed polymyxin B resistance in vivo. All polymyxin B-resistant isolates had lower growth rates than and substitution mutations in the lpx or pmrB gene compared to their parent isolates. There were significant differences in terms of antibiotic susceptibility and genetic determinants of resistance in A. baumannii isolates that had developed polymyxin B resistance in vivo compared to isolates that had developed polymyxin B resistance in vitro.     

18F-FDG PET/CT imaging for a gastrointestinal mantle cell lymphoma with multiple lymphomatous polyposis

Multiple lymphomatous polyposis(MLP)is an uncommon type of gastrointestinal lymphoma characterized by the presence of multiple polyps along the gastrointestinal tract.Most of this entity is in fact considered the counterpart of gastrointestinal tract involvement for mantle cell lymphoma(MCL).To our knowledge,there have been no reports on[fluorine-18]-fluorodeoxy-glucose(18F-FDG)-positron emission tomography(PET)/computed tomography(CT)imaging for gastrointestinal MCL with MLP.We present the results of 18F-FDG PET/CT imaging in a patient with gastrointestinal tract involvement of MCL showing continuous MLP from the stomach to the rectum and intestinal intussusception.FDG-PET/CT findings were false negative in typical MLP spreading widely over the gastrointestinal tract,but uptake was noted in large lesions with deep infiltration considered atypical as MLP.On FDG-PET/CT imaging,the Ki-67proliferative index,which is a cell proliferation marker,showed neither correlation with the presence of uptake nor the maximum standardized uptake value.     

Diagnosing peripheral neuropathy in South‐East Asia: A focus on diabetic neuropathy

Burning and stabbing pain in the feet and lower limbs can have a significant impact on the activities of daily living, including walking, climbing stairs and sleeping. Peripheral neuropathy in particular is often misdiagnosed or underdiagnosed because of a lack of awareness amongst both patients and physicians. Furthermore, crude screening tools, such as the 10‐g monofilament, only detect advanced neuropathy and a normal test will lead to false reassurance of those with small fiber mediated painful neuropathy. The underestimation of peripheral neuropathy is highly prevalent in the South‐East Asia region due to a lack of consensus guidance on routine screening and diagnostic pathways. Although neuropathy as a result of diabetes is the most common cause in the region, other causes due to infections (human immunodeficiency virus, hepatitis B or C virus), chronic inflammatory demyelinating polyneuropathy, drug‐induced neuropathy (cancer chemotherapy, antiretrovirals and antituberculous drugs) and vitamin deficiencies (vitamin B₁, B₆, B₁₂, D) should be actively excluded.     

Macrophage activation and skeletal muscle healing following traumatic injury

Following injury to different tissues, macrophages can contribute to both regenerative and fibrotic healing. These seemingly contradictory roles of macrophages may be related to the markedly different phenotypes that macrophages can assume upon exposure to different stimuli. We hypothesized that fibrotic healing after traumatic muscle injury would be dominated by a pro‐fibrotic M2a macrophage phenotype, with M1 activation limited to the very early stages of repair. We found that macrophages accumulated in lacerated mouse muscle for at least 21 days, accompanied by limited myofibre regeneration and persistent collagen deposition. However, muscle macrophages did not exhibit either of the canonical M1 or M2a phenotypes, but instead up‐regulated both M1‐ and M2a‐associated genes early after injury, followed by down‐regulation of most markers examined. Particularly, IL‐10 mRNA and protein were markedly elevated in macrophages from 3‐day injured muscle. Additionally, though flow cytometry identified distinct subpopulations of macrophages based on high or low expression of TNFα, these subpopulations did not clearly correspond to M1 or M2a phenotypes. Importantly, cell therapy with exogenous M1 macrophages but not non‐activated macrophages reduced fibrosis and enhanced muscle fibre regeneration in lacerated muscles. These data indicate that manipulation of macrophage function has potential to improve healing following traumatic injury. Copyright © 2013 Pathological Society of Great Britain and Ireland. Published by John Wiley & Sons, Ltd.