Tuesday, November 06, 2012
Crohn's disease in children may start from bacteria
Crohn's disease in children may start from bacteria
Nov 5, 2012
Certain types of bacteria may cause and maintain Crohn’s disease, according to a new study.
Crohn’s causes inflammation of the digestive system. Symptoms include abdominal pain, diarrhea, weight loss, joint pain, skin problems, fever and bleeding from the rectum.
In this study, researchers found that 19 children newly diagnosed with Crohn’s disease had different levels of a group of bacteria called proteobacteria, which include E. coli and Campylobacter concisus.
The researchers also checked bacteria levels in 21 healthy children.
Patients with mild Crohn’s had higher levels of proteobacteria in their intestinal tracts than those with moderate to severe disease and children without Crohn’s disease.
This suggests that these types of bacteria may play a role in causing the disease, said study principal investigator Hazel Mitchell of the University of New South Wales, in Australia.
The findings may help lead to new treatments that target intestinal bacteria.
The study was published in the October issue of the Journal of Clinical Microbiology.
“We deliberately chose to examine children newly diagnosed with Crohn’s disease, as we thought this would increase our chances of detecting species that may be involved in initiating Crohn’s disease,” Mitchell said in a journal news release.
Mitchell explained that factors that can affect bacteria in the intestinal tract — such as the use of antibiotics or anti-inflammatory drugs, smoking or alcohol consumption — are less likely to be present in children than in adults.
Labels: abdominal pain, bacteria, bleeding, Crohn's disease, diarrhea, digestive system, fever, inflammation, joint pain, Proteobacteria, skin problems, weight loss
# posted by Pat O'Connor @ 8:12 AM
Sunday, October 21, 2012
Monitoring Bacterial Burden, Inflammation and Bone Damage Longitudinally Using Optical and μCT Imaging in an Orthopaedic Implant Infection in Mice.
Monitoring Bacterial Burden, Inflammation and Bone Damage Longitudinally Using Optical and μCT Imaging in an Orthopaedic Implant Infection in Mice.
2012
Niska JA, Meganck JA, Pribaz JR, Shahbazian JH, Lim E, Zhang N, Rice BW, Akin A, Ramos RI, Bernthal NM, Francis KP,Miller LS.
Source
Orthopaedic Hospital Research Center, Orthopaedic Hospital Department of Orthopaedic Surgery, David Geffen School of Medicine at University of California Los Angeles (UCLA), Los Angeles, California, United States of America.
Abstract
BACKGROUND:
Recent advances in non-invasive optical, radiographic and μCT imaging provide an opportunity to monitor biological processes longitudinally in an anatomical context. One particularly relevant application for combining these modalities is to study orthopaedic implant infections. These infections are characterized by the formation of persistentbacterial biofilms on the implanted materials, causing inflammation, periprosthetic osteolysis, osteomyelitis, and bone damage, resulting in implant loosening and failure.
METHODOLOGY/PRINCIPAL FINDINGS:
An orthopaedic implant infection model was used in which a titanium Kirshner-wire was surgically placed in femurs of LysEGFP mice, which possess EGFP-fluorescent neutrophils, and a bioluminescent S. aureus strain (Xen29; 1×10(3) CFUs) was inoculated in the knee joint before closure. In vivo bioluminescent, fluorescent, X-ray and μCT imaging were performed on various postoperative days. The bacterial bioluminescent signals of the S. aureus-infected mice peaked on day 19, before decreasing to a basal level of light, which remained measurable for the entire 48 day experiment. Neutrophil EGFP-fluorescent signals of the S. aureus-infected mice were statistically greater than uninfected mice on days 2 and 5, but afterwards the signals for both groups approached background levels of detection. To visualize the three-dimensional location of the bacterial infection and neutrophil infiltration, a diffuse optical tomography reconstruction algorithm was used to co-register the bioluminescent and fluorescent signals with μCT images. To quantify the anatomical bone changes on the μCT images, the outer bone volume of the distal femurs were measured using a semi-automated contour based segmentation process. The outer bone volume increased through day 48, indicating that bone damage continued during the implant infection.
CONCLUSIONS/SIGNIFICANCE:
Bioluminescent and fluorescent optical imaging was combined with X-ray and μCT imaging to provide noninvasive and longitudinal measurements of the dynamic changes in bacterial burden, neutrophil recruitment and bone damage in a mouse orthopaedic implant infection model.
Labels: bacterial burden, Bioluminescent imaging, bone damage, fluorescent optical imaging, inflammation, periprosthetic osteolysi
# posted by Pat O'Connor @ 8:48 AM
Wednesday, September 19, 2012
Dietzia species pacemaker pocket infection: an unusual organism in human infections.
Dietzia species pacemaker pocket infection: an unusual organism in human infections
Sept 2012
.
Source
Cardiology Department, Conquest Hospital, St Leonards-on-Sea, East Sussex, UK.
Abstract
An 87-year-old man presented 10 months following permanent pacemaker insertion with cellulitis-like inflammation around the impulse generator. Symptoms improved with oral flucloxacillin, but only days after stopping, the infection recurred, and he was admitted from clinic for intravenous antibiotics. Suspecting the source was likely Staphylococcal, intravenous flucloxacillin was started, and the patient's inflammatory markers responded adequately. Two samples of fluid were aspirated from the pacemaker site. These showed no bacterial growth using routine microbiological culture techniques. The samples were sent for 16S rDNA PCR and Dietzia species was detected in both samples. Dietzia species is an Actinomyces-like organism, which is not commonly associated with human infection, but is reported to have been isolated from clinical specimens and thus presumptively associated with human disease. The pacemaker was explanted and the pocket debrided with no complications. He made a full recovery after a prolonged course of flucloxacillin.
Labels: Dietzia species, flucloxacillin, human infection, inflammation, intravenous antibiotics, oral flucloxacillin, pacemaker
# posted by Pat O'Connor @ 8:58 AM
