Clinical and Microbiologic Investigation of an Expedited Peri-implantitis Dog Model: An Animal Study

Background: Animal studies are pivotal in allowing experimentation to identify efficacious treatment protocols for resolution of peri-implantitis. The purpose of this investigation was to characterize an expedited dog peri-implantitis model clinically, radiographically, and microbiologically. Methods: Eight hound dogs underwent extractions (week 0) and implant (3.3 × 8.5 mm) placement with simultaneous surgical defect creation and ligature placement for induction of peri-implantitis (week 10). Ligatures were replaced at 6 weeks (week 16) and removed after 9 weeks (week 19) when supporting bone loss involved approximately 50% of the peri-implant bone. Microbial samples from the defects and healthy control implant sites collected at week 19 were analyzed utilizing a microarray. Clinical measures of inflammation were obtained and radiographic bone loss was measured from periapical radiographs. Radiographic depth and width measurements of bony defect were repeated at weeks 10 (baseline), 16, and 19. Canonical analysis of principal coordinates was used to visualize overall differences in microbial abundance between peri-implantitis and healthy implants. Results: This accelerated disease protocol led to intrabony defect creation with a mean depth and width of 4.3 mm and 3.5 mm, respectively after 9 weeks of ligature placement. Microbial identification revealed 59 total bacteria in peri-implant sites, 21 of which were only present in peri-implant sites as compared to healthy controls. Overall microbial beta diversity (microbial between-sample compositional diversity) differed between peri-implantitis and healthy implants (p = 0.009). Conclusions: Within the limitations of this study, this protocol led to expedited generation of peri-implant defects with a microbial profile indicative of a shift to disease and defect patterns conducive to regenerative treatment. However, the possibility of potential spontaneous resolution of lesions due to the lack of a chronicity interval as compared to chronic disease models need to be further clarified and considered during preclinical peri-implantitis model selection

Obstructive ileus caused by phlebosclerotic colitis

A 57-year-old man with chronic kidney disease and a history of using numerous herbal medications visited Inje University Ilsan Paik Hospital for abdominal pain and vomiting. An abdominal radiograph showed diffuse small bowel distension containing multiple air-fluid levels and extensive calcifications along the colon. Computed tomography showed colon wall thickening with diffuse calcification along the colonic mesenteric vein and colonic wall. Colonoscopy, performed without bowel preparation, showed bluish edematous mucosa from the transverse to the distal sigmoid colon, with multiple scar changes. At the mid transverse colon, a stricture was noted and the scope could not pass through. A biopsy of the stricture site revealed nonspecific changes. The patient was diagnosed with phlebosclerotic colitis. After the colonoscopy, the obstructive ileus spontaneously resolved, and the patient was discharged without an operation. Currently, after 2 months of follow-up, the patient has remained asymptomatic. Herein, we report the rare case of an obstructive ileus caused by phlebosclerotic colitis with a colon stricture

The Effect of Apolipoprotein E Polymorphism on Lipid Levels in Korean Adults

The aim of this study was to determine the effects of polymorphisms in the apolipoprotein E gene (APOE) on lipid levels in Korean adults and to investigate the interactions between these polymorphisms and environmental factors in determining lipid levels. We performed a cross-sectional study of 1,900 subjects (668 men and 1,232 women; 45-74 yr old) in Namwon, Korea, in 2004. APOE polymorphisms were determined by polymerase chain reaction and restriction enzyme analysis. Carriers of the APOE*E2 (E2) allele had significantly lower total cholesterol and low-density lipoprotein cholesterol (LDL-C) concentrations than did carriers of the APOE*E3 (E3) or APOE*E4 (E4) alleles, regardless of gender. The APOE allele type had significant effect on high-density lipoprotein cholesterol (HDL-C) and triglyceride levels in women, but not in men. The effect of APOE allele type on HDL-C levels was modified by age in women. In addition, in men, the effect of APOE allele type on triglyceride levels was modified by smoking. These findings highlight the important effect of gene-environment interactions on lipid levels

Analysis of Methicillin Resistance among Staphylococcus aureus Blood Isolates in an Emergency Department

The increasing prevalence of methicillin-resistant Staphylococcus aureus (MRSA) has become of great concern in both hospital and community settings. To evaluate the prevalence and risk factors for methicillin resistance among Staphylococcus aureus, blood isolates in our Emergency Department (ED) were collected. All patients with S. aureus bacteremia (SAB) who presented to the ED from January 2000 to August 2005 were included, and a retrospective study was performed. A total of 231 patients with SAB were enrolled (median age, 59 yr; M:F, 125:106). Among these patients, methicillin-resistant strains accounted for 27.3% (63 patients). Catheter-related infection was the most frequent primary site of SAB (39.0%), followed by skin and soft tissue infection (16.5%). In multivariate analysis, recent surgery (OR, 3.41; 95% CI, 1.48-7.85), recent hospitalization (2.17; 1.06-4.62), and older age (≥61 yr) (2.39; 1.25-4.57) were independently associated with the acquisition of methicillin-resistant strains. When antimicrobial therapy is considered for the treatment of a patient with suspected SAB, clinicians should consider obtaining cultures and modifying empirical therapy to provide MRSA coverage for patients with risk factors: older age, recent hospitalization, and recent surgery

Quantitative Ultrasound of the Calcaneus in a Korean Population: Reference Data and Relationship to Bone Mineral Density Determined by Peripheral Dual X-ray Absorptiometry

The aim of this study was to establish reference data for the quantitative ultrasound (QUS) of the calcaneus and for the bone mineral densities (BMD) of the calcaneus and distal forearm, and to evaluate the correlation between QUS parameters and BMD in a Korean population. We performed a cross-sectional study involving 3,053 subjects (1,225 men and 1,828 women). QUS was conducted on the calcaneus and was quantified as speed of sound (SOS, m/sec), broadband ultrasound attenuation (BUA, dB/MHz), and stiffness index. The BMD of the calcaneus and distal forearm were measured using dual X-ray absorptiometry. The peak mean values for the QUS parameters occurred in the 20 to 29-yr-old subjects of both sexes, with the exception of the BUA, which reached the highest values in women of 30-39 yr. For both sexes, the mean BMD of the calcaneus was highest in those 20-29 yr old and that of the distal forearm was highest in those 40-49 yr old. The correlations between the QUS and BMD results were found to be 0.41 to 0.73 in men and 0.51 to 0.76 in women. Theses data can serve as a reference values for both sexes in Korea

High Dose Vitamin D3 Attenuates the Hypocalciuric Effect of Thiazide in Hypercalciuric Rats

Thiazide is known to decrease urinary calcium excretion. We hypothesized that thiazide shows different hypocalciuric effects depending on the stimuli causing hypercalciuria. The hypocalciuric effect of hydrochlorothiazide (HCTZ) and the expression of transient receptor potential vanilloid 5 (TRPV5), calbindin-D28K, and several sodium transporters were assessed in hypercalciuric rats induced by high calcium diet and vitamin D3. Urine calcium excretion and the expression of transporters were measured from 4 groups of Sprague-Dawley rats; control, HCTZ, high calcium-vitamin D, and high calcium-vitamin D with HCTZ groups. HCTZ decreased urinary calcium excretion by 51.4% in the HCTZ group and only 15% in the high calcium-vitamin D with HCTZ group. TRPV5 protein abundance was not changed by HCTZ in the high calcium-vitamin D with HCTZ group compared to the high calcium-vitamin D group. Protein abundance of NHE3, SGLT1, and NKCC2 decreased in the hypercalciuric rats, and only SGLT1 protein abundance was increased by HCTZ in the hypercalciuric rats. The hypocalciuric effect of HCTZ is attenuated in high calcium and vitamin D-induced hypercalciuric rats. This attenuation seems to have resulted from the lack of HCTZ's effect on protein abundance of TRPV5 in severe hypercalciuric condition induced by high calcium and vitamin D

Effects of Thiazide on the Expression of TRPV5, Calbindin-D28K, and Sodium Transporters in Hypercalciuric Rats

TRPV5 is believed to play an important role in the regulation of urinary calcium excretion. We assessed the effects of hydrochlorothiazide (HCTZ) on the expression of TRPV5, calbindin-D28K, and several sodium transporters in hypercalciuric rats. Sprague-Dawley rats were divided into 4 groups; control, HCTZ, high salt, and high salt with HCTZ group in experiment 1; control, HCTZ, high calcium (Ca), and high Ca with HCTZ group in experiment 2. To quantitate the expression of TRPV5, calbindin-D28K, and sodium transporters, western blotting was performed. In both experiments, HCTZ significantly decreased urinary calcium excretion. TRPV5 protein abundance decreased in all hypercalciuric rats, and restored by HCTZ in both high salt with HCTZ and high Ca with HCTZ group. Calbindin-D28K protein abundance increased in the high salt and high salt with HCTZ groups, but did not differ among groups in experiment 2. Protein abundance of NHE3 and NKCC2 decreased in all hypercalciuric rats, and were restored by HCTZ in only high Ca-induced hypercalciuric rats. In summary, protein abundance of TRPV5, NHE3, and NKCC2 decreased in all hypercalciuric rats. The hypocalciuric effect of HCTZ is associated with increased protein abundance of TRPV5 in high salt or calcium diet-induced hypercalciuric rats

Catheter-associated bacteremia by Mycobacterium senegalense in Korea

BACKGROUND: Rapidly growing mycobacteria is recognized as one of the causative agents of catheter-related infections, especially in immunocompromised hosts. To date, however, Mycobacterium senegalense, which was known as the principal pathogen of bovine farcy, has not been reported in human infection. CASE PRESENTATION: We describe the first case of human infection by M. senegalense, which has caused catheter-related bloodstream infection in a cancer patient in Korea. The microorganism was identified by the 16S rRNA gene, rpoB, and 16S-23S rRNA gene internal transcribed spacer (ITS) sequence analyses. CONCLUSION: Our first report of catheter-associated bacteremia caused by M. senegalense suggests the zoonotic nature of this species and indicates the expansion of mycobacterial species relating to human infection. M. senegalense should be considered as one of the causes of human infections in the clinical practice

Modulating Temporal and Spatial Oxygenation over Adherent Cellular Cultures

Oxygen is a key modulator of many cellular pathways, but current devices permitting in vitro oxygen modulation fail to meet the needs of biomedical research. A microfabricated insert for multiwell plates has been developed to more effectively control the temporal and spatial oxygen concentration to better model physiological phenomena found in vivo. The platform consists of a polydimethylsiloxane insert that nests into a standard multiwell plate and serves as a passive microfluidic gas network with a gas-permeable membrane aimed to modulate oxygen delivery to adherent cells. Equilibration time is on the order of minutes and a wide variety of oxygen profiles can be attained based on the device design, such as the cyclic profile achieved in this study, and even oxygen gradients to mimic those found in vivo. The proper biological consequences of the device's oxygen delivery were confirmed in cellular models via a proliferation assay and western analysis of the upregulation of hypoxia inducible transcription factor-1α. These experiments serve as a demonstration for the platform as a viable tool to increase experimental throughput and permit novel experimental possibilities in any biomedical research lab