The visualisation and speed of kill of wound isolates on a silver alginate dressing

In chronic wound management, alginate dressings are used to absorb exudate and reduce the microbial burden. Silver alginate offers the added benefit of an additional antimicrobial pressure on contaminating microorganisms. This present study compares the antimicrobial activity of a RESTORE silver alginate dressing with a silver‐free control dressing using a combination of in vitro culture and imaging techniques. The wound pathogens examined included Candida albicans, Escherichia coli, Pseudomonas aeruginosa, Staphylococcus aureus, β‐haemolytic Streptococcus, and strictly anaerobic bacteria. The antimicrobial efficacy of the dressings was assessed using log₁₀ reduction and 13‐day corrected zone of inhibition (CZOI) time‐course assays. Confocal laser scanning microscopy (CLSM) was used to visualise the relative proportions of live/dead microorganisms sequestered into the dressings over 24 hours and estimate the comparative speed of kill. The RESTORE silver alginate dressing showed significantly greater log₁₀ reductions and CZOIs for all microorganisms compared with the control, indicating the antimicrobial effect of ionic silver. Antimicrobial activity was evident against all test organisms for up to 5 days and, in some cases, up to 12 days following an on‐going microbial challenge. Imaging bacteria sequestered in the silver‐free dressing showed that each microbial species aggregated in the dressing and remained viable for more than 20 hours. Growth was not observed inside of the dressing, indicating a possible microbiostatic effect of the alginate fibres. In comparison, organisms in the RESTORE silver alginate dressing were seen to lose viability at a considerably greater rate. After 16 hours of contact with the RESTORE silver alginate dressing, >90% of cells of all bacteria and yeast were no longer viable. In conclusion, collectively, the data highlights the rapid speed of kill and antimicrobial suitability of this RESTORE silver alginate dressing on wound isolates and highlights its overwhelming ability to manage a microbial wound bioburden in the management of infected wounds.     

Detection of total knee prostheses at airport security checkpoints

Airport security screening measures have changed substantially during the past decade, but few reports have examined how this affects patients who have undergone knee arthroplasties. The purpose of this study was to characterize the efficacy of airport metal detection of total knee prostheses, the delays faced, any inconvenience this may have caused, and the role of implant identification cards. Ninety-seven total knee arthroplasty recipients reported passing through an airport metal detector, with 70 triggering the alarm a mean of 3 times (range, 1-36). The presence of a single-knee prosthesis triggered airport security alarms more than 83% of the time and increased patient inconvenience. Patients should be informed about this chance and be prepared to present documentation of their prosthesis.     

Osteotomy and Unicompartmental Knee Arthroplasty Converted to Total Knee Arthroplasty : Data From the New Zealand Joint Registry

We reviewed the revision rate and functional outcome of all patients who had a total knee arthroplasty (TKA) after an osteotomy or unicompartmental knee arthroplasty (UKA) on the New Zealand Joint Registry. We used these data to compare the results with primary TKA scores, including comparison of age-matched subgroups. There were 711 patients who had undergone TKA as salvage for a failed osteotomy with a revision rate of 1.33 per 100 component years and a mean 6-month Oxford Knee Score (OKS) of 36.9. There were 205 patients who had a failed UKA converted to TKA with a revision rate of 1.97 per 100 component years and a mean OKS of 29.1. The revision rates of TKA for both failed osteotomy and failed UKA were significantly poorer than after primary TKA (0.48 per 100 component years). The mean OKS after revision of a UKA was significantly poorer than both primary TKA and TKA for a failed osteotomy. There was no significant difference in mean OKS between primary TKA and TKA for a failed osteotomy, even among patients younger than 65 years. Revision of a failed osteotomy to a TKA has improved functional results compared with revision of a failed UKA. However, both yield poorer survivorship rates compared with primary TKA.     

Neutrophil Gelatinase-Associated Lipocalin: Its Response to Hypoxia and Association with Acute Mountain Sickness

Acute Mountain Sickness (AMS) is a common clinical challenge at high altitude (HA). A point-of-care biochemical marker for AMS could have widespread utility. Neutrophil gelatinase-associated lipocalin (NGAL) rises in response to renal injury, inflammation and oxidative stress. We investigated whether NGAL rises with HA and if this rise was related to AMS, hypoxia or exercise. NGAL was assayed in a cohort (n = 22) undertaking 6 hours exercise at near sea-level (SL); a cohort (n = 14) during 3 hours of normobaric hypoxia (FiO2 11.6%) and on two trekking expeditions (n = 52) to over 5000 m. NGAL did not change with exercise at SL or following normobaric hypoxia. During the trekking expeditions NGAL levels (ng/ml, mean ± sd, range) rose significantly (P < 0.001) from 68 ± 14 (60–102) at 1300 m to 183 ± 107 (65–519); 143 ± 66 (60–315) and 150 ± 71 (60–357) at 3400 m, 4270 m and 5150 m respectively. At 5150 m there was a significant difference in NGAL between those with severe AMS (n = 7), mild AMS (n = 16) or no AMS (n = 23): 201 ± 34 versus 171 ± 19 versus 124 ± 12 respectively (P = 0.009 for severe versus no AMS; P = 0.026 for mild versus no AMS). In summary, NGAL rises in response to prolonged hypobaric hypoxia and demonstrates a relationship to the presence and severity of AMS.     

Clinical effects of an essential oil solution used as a coolant during ultrasonic root debridement

To cite this article: Int J Dent HygieneDOI: 10.1111/j.1601‐5037.2012.00554.x
Cosyn J, Miremadi SR, Sabzevar MM, De Bruyn H. Clinical effects of an essential oil solution used as a coolant during ultrasonic root debridement. Abstract: Aim: The use of chlorhexidine and povidone iodine solutions applied as a coolant during ultrasonic root debridement for the treatment of chronic periodontitis has been described. Hitherto, this application has not yet been extensively investigated for essential oil solutions. The goal was to clinically explore this and to compare to water irrigation. Materials and methods: Thirty‐five chronic periodontitis patients participated in a single‐blind randomized controlled clinical study. Patients were randomly allocated to the control group (n = 18) or test group (n = 17) receiving oral hygiene instructions and ultrasonic root debridement using water as a coolant, respectively, a pure essential oil solution. Oral hygiene was reinforced if necessary at each occasion, and clinical parameters were collected at baseline and after 1 and 3 months. Results: Significant pocket reduction (control, 1.02 mm; test, 0.89 mm) and clinical attachment gain (control and test, 0.48 mm) were shown in both groups. However, there were no significant differences between the groups at any point in time for any of the parameters. Conclusion: Essential oil solutions do not offer a clinical benefit over water when used as a coolant during ultrasonic root debridement for the treatment of chronic periodontitis.     

P53 nuclear stabilization is associated with <Emphasis Type="Italic">FHIT</Emphasis> loss and younger age of onset in squamous cell carcinoma of oral tongue

Background

Squamous cell carcinoma of tongue (SCCT) is expected to harbor unique clinico-pathological and molecular genetic features since a significant proportion of patients are young and exhibit no association with tobacco or alcohol.

Methods

We determined P53, epidermal growth factor receptor, microsatellite instability, human papilloma virus infection and loss of heterozygosity status at several tumor suppressor loci in one hundred and twenty one oral SCCT (SSCOT) samples and analyzed their association with clinico-pathological features and patient survival.

Results

Our results revealed a significantly higher incidence of p53 nuclear stabilization in early (as against late) onset SCCOT. FHIT loss was significantly associated with p53 nuclear stabilization and the association was stronger in patients with no history of tobacco use. Samples harboring mutation in p53 DNA binding domain or exhibiting p53 nuclear stabilization, were significantly associated with poor survival.

Conclusion

Our study has therefore identified distinct features in SCCOT tumorigenesis with respect to age and tobacco exposure and revealed possible prognostic utility of p53.

     

Comparison of Primary Open Angle Glaucoma Patients in Rural and Urban Ghana

Purpose

To compare the clinical features of glaucoma patients who present at a rural hospital in North Eastern Ghana and an urban hospital in the capital city of Accra.

Methods

This is a multi-center retrospective case series involving records of newly diagnosed glaucoma patients with emphasis on primary open angle glaucoma (POAG). Information collected included basic demographic data, intraocular pressures and optic disc measurements.

Results

A total of 949 patients (437 rural; 512 urban; 1868 eyes) were included. Rural vs. urban comparisons, respectively: mean age, 53.2 ± 16.3 vs. 54.5 ± 16.4 years; male: female ratio, 3:2 vs. 1:1; POAG, 78.1% vs. 50.6%; POAG suspect, 10.3% vs. 41.9%; IOP, 39.2 ± 7.1 vs. 31.8 ± 7.3 mmHg; bilateral blindness, 34.1% vs. 17.5%; uniocular blindness, 52.2% vs. 32.9%. Females at the rural hospital were twice as likely to present blind in at least one eye (OR 2.04, CI 1.36 – 3.07, p<0.001).

Conclusions

Patients with POAG at the rural hospital present with more advanced disease characteristics.     

Differences in glucose‐stimulated insulin secretion in vitro of islets from human,nonhuman primate,and porcine origin

Porcine islet xenotransplantation is considered a potential cell‐based therapy for type 1 diabetes. It is currently being evaluated in diabetic nonhuman primates (NHP) to assess safety and efficacy of the islet product. However, due to a variety of distinct differences between the respective species, including the insulin secretory characteristics of islets, the suitability and predictive value of the preclinical model in the extrapolation to the clinical setting remain a critical issue. Islets isolated from human (n = 3), NHP (n = 2), adult pig (AP, n = 3), and juvenile pig (JP, n = 4) pancreata were perifused with medium at basal glucose (2.5 mm ) followed by high glucose (16.7 mm ) concentrations. The total glucose‐stimulated insulin secretion (GSIS) was calculated from generated insulin secretion profiles. Nonhuman primate islets exhibited GSIS 3‐fold higher than AP islets, while AP and JP islets exhibited GSIS 1/3 and 1/30 of human islets, respectively. The insulin content of NHP and AP islets was similar to that of human islets, whereas that of JP islets was 1/5 of human islets. Despite the fact that human, NHP, and AP islets contain similar amounts of insulin, the much higher GSIS for NHP islets than for AP and JP islets suggests the need for increased dosing of islets from JP and AP in pig‐to‐NHP transplantation. Porcine islet xenotransplantation to humans may require significantly higher dosing given the lower GSIS of AP islets compared to human islets.