Antimicrobial FiteBac® K21 promotes antimicrobial Potency and wound healing

Objectives

Successful root canal therapy is dependent on the efficacy of complete instrumentation and adequate use of chemical irrigant to eliminate the biofilm from dentin surface. The aim of the study was to examine antibiofilm and antimicrobial effectiveness of newly formulated Quaternary ammonium silane (QAS/also codenamed K21; against Fusobacterium nucleatum (F. nucleatum) and Enterococcus faecalis (E. faecalis) biofilm on radicular dentin with evaluation of the anti-inflammatory consequence in vivo.

Methods

Fourier Transform Infrared Spectroscopy (FTIR) was performed after complete hydrolysis of K21 solution. Human teeth were inoculated with biofilms for 7-days followed by treatment with various irrigants. The irrigant groups were Sodium hypochlorite [NaOCl (6%)], Chlorhexidine [CHX (2%)], K21 (0.5%), K21 (1%) and Saline. Scanning electron microscopy (SEM) was performed for biofilm and resin-dentin penetration. Transmission Electron Microscopy (TEM) of biofilms was done to evaluate application of K21. For in vivo evaluation, Albino wistar rats were injected subcutaneously and sections were stained with haematoxylin/eosin. Macrophage, M1/M2 expression were evaluated along with molecular simulation. Raman measurements were done on dried biofilms.

Results

FTIR K21 specimens demonstrated presence of ethanol/silanol groups. Raman band at 1359 cm-1 resemble to -CH2- wagging displaying 29Si atoms in Nuclear Magnetic Resonance (NMR). 0.5%K21 showed cells exhibiting folded membranes. SEM showed staggering amount of resin tags with 0.5% K21 group. TEM showed membrane disruption in K21-groups. K21 groups were initially irritant, which subsided completely afterwards showing increased CD68. K21 and MMP/collagen complex was thermodynamically favourable.

Conclusion

K21 root canal irrigant was able to penetrate bacterial wall and can serve as a potential irrigant for therapeutic benefits. Expression of M2 polarized subsets showed K21 can serve in resolving inflammation and potentiate tissue repair.

Evidence-based dentistry: Knowledge, Practice, Confidence and Attitude amongst Malaysian dental undergraduate students: A Multi-institutional study

INTRODUCTION

Evidence-based dental practice provides patient-centred, compatible and efficient interventions and forms the basis for health profession education. So far, there is a paucity of data about Malaysian undergraduate dental education and the role of evidence-based dentistry in it. The current research aimed to study the level of knowledge, attitude, practice and confidence of dental undergraduate students in Malaysia towards evidence-based dental practice.

METHODS

This cross-sectional study included final-year undergraduate dental students (N = 645) who completed a pre-tested self-administered questionnaire that analysed the domains of perceived knowledge, practice, critical appraisal and attitude towards evidence-based dentistry. We further explored the association between these domains with the type of curriculum, sex, prior research experience and EBD training.

RESULTS

A total of (n = 526) students participated (response rate of 81.55%). About 92% knew about evidence-based dentistry. Whilst 58% had undergone formal training in evidence-based dentistry, 90% of the respondents showed an overall positive attitude towards evidence-based dentistry. However, only 45% of them practised it most of the time. Schools with an integrated curriculum showed more willingness and practised evidence-based dentistry more frequently (p < 0.001). More than 50% of the participants rated their confidence in appraisal as moderate.

CONCLUSION

Our findings revealed that Malaysian dental undergraduate students who are well aware of evidence-based dentistry displayed a positive attitude towards it. The type of dental curriculum had a significant association with practice and attitude towards evidence-based dental knowledge and practice.

Comparison of Digital Interactive Case-Based Educational Resource with Virtual Role Play in Dental Undergraduates in Clinical Oral Medicine/Oral Pathology Education

Case-based learning has always been a key element of dental education and the incorporation of technology into the concept became increasingly important during the COVID-19 pandemic. This study aimed to compare the effectiveness of a virtual interactive case resource in oral medicine/oral pathology, Virtual Oral Medicine Clinic (VOMC), with the virtual role play among third-year dental undergraduates. Fifty-one students were randomly assigned into two groups and the control group was subjected to a role play activity, whereas the experimental group was provided with VOMC. Both groups were assessed with an objective structured clinical examination (OSCE) before and after the intervention. Students’ self-perceived usefulness of the interventions was evaluated by a questionnaire and randomly selected students were invited for focus group discussions. Data were analysed using the Wilcoxon signed-rank test and the Mann−Whitney U test. Descriptive statistics were used to analyse student responses. Students in both groups demonstrated significant improvement (p < 0.001) in the post-test compared to the pre-test. Students in the experimental group demonstrated higher overall scores (p < 0.001) when compared to the control group. Though both methods were received favourably by the students, role play was more positively perceived when compared to digital resource. Though VOMC was shown to improve student scores, the perception of VOMC was not quantitatively superior to the role play activity. Hence VOMC can be recommended as an adjunct tool to enhance learning in oral medicine in undergraduate dental students.

Current and future trends in the teaching of removable partial dentures in dental schools in Malaysia: A cross sectional study

AIMS

To investigate, using a validated questionnaire, the teaching of removable partial dentures (RPDs) in dental schools of Malaysia.

MATERIALS AND METHODS

A validated questionnaire to investigating trends in the teaching of RPDs in dental schools in Oceania was emailed (in English version form) to Heads of Restorative/Prosthodontics/course coordinators in the 13 dental schools in Malaysia. Follow-up reminders were sent and participants were given six weeks to complete and return the questionnaire. Data was entered into an Excel spreadsheet and results compiled and analyzed.

RESULTS

Completed questionnaires were received from 13 dental school - a 100% response rate. All schools (n = 13) provided a preclinical technical course in RPD design. In most schools (n = 9, 69.2%), course work was supervised by senior lecturers while rest of the institutions made use of associate professor/professors. There were significant differences (p<0.05) between dental schools in terms of the contact hours dedicated to preclinical teaching. Students received an average of 62 h of instruction. Didactic instruction was the primary focus with practical (78 h) and didactic teaching (32 h). All dental schools (n = 13) provided practical surveyor design teaching (8 h). The staff student ratio for formal lectures (1:61), tutorials (1:29) and lab demonstrations (1:12) were recorded. Majority of the schools (n = 11, 84.6%) employed paired teaching in clinical sessions. All schools (n = 13, 100%) emphasized on increased teaching of RPD design and prescription writing in future clinical RPD courses.

CONCLUSION

Teaching of RPDs in Malaysia may be considered sufficient and comparable to the teaching in other parts of the world.

CLINICAL SIGNIFICANCE

Whilst the teaching of partial dentures at Dental Schools in Malaysia provides the core competencies involved in partial denture design and construction based on sound fundamental, scientific principles they should address the challenges of teaching partial dentures and other areas of dental education including improving working conditions for dental professionals.

Prevalence of dens invaginatus and its association with periapical lesions in a Western Indian population-a study using cone-beam computed tomography

OBJECTIVES

This study aimed to assess the prevalence of dens invaginatus (DI) and its association with periapical lesions (PLs) in a Western Indian population by means of cone-beam computed tomography (CBCT).

MATERIALS AND METHODS

CBCT volumes of 5201 subjects were evaluated. Associations among gender, tooth type, DI type (Oehler's classification), and presence of PL were investigated. PL was codified using Estrela's Cone Beam Computed Tomography Periapical Index (CBCTPAI). Chi-square tests and descriptive statistics were used at p = 0.05.

RESULTS

Overall, 7048 CBCTs were assessed, containing 19,798 maxillary and mandibular anteriors, of which 77 maxillary teeth demonstrated DI (0.39% of all anteriors). Of all 5201 subjects, 57 had DI (1.1%). Bilateral DI was more common in females than in males (p = 0.046). DI type distribution was as follows: type I (22.1%), type II (61.03%), type IIIa (10.4%), and type IIIb (6.5%), which was significantly different (p < 0.001). Maxillary lateral incisors were the most associated with PL (p < 0.001). Type I was frequently associated with CBCTPAI scores 1 and 2 (absence of PL), whereas types II, IIIa, and IIIb were associated with CBCTPAI scores 3, 4, and 5 (presence of PL).

CONCLUSIONS

A prevalence of 1.1% identifies DI as a common developmental tooth anomaly in a Western Indian subpopulation. The percentage of maxillary anteriors affected by DI and associated PLs should be considered before diagnosis and treatment planning.

CLINICAL RELEVANCE

Knowledge about the prevalence of DI and its subtypes, and their association with/without periapical pathosis may aid clinicians in treatment planning and execution to improve patient outcomes.

Clinical and cytological findings in oral cavity of young shisha smokers and non-smokers – a comparative study

Introduction: Shisha, a form of smoking tobacco is known to be detrimental to oral health. Yet, the effects of shisha on oral health is not well documented. Hence, this study was undertaken to compare the clinical and cytological findings in oral cavity of young shisha smokers as compared to non-smokers. Materials and methods: A cross-sectional analytical study was undertaken among 60 subjects including 30 young shisha smokers and 30 non-smokers. Clinical examination was carried out to record gingival status, periodontal status, oral hygiene and dental caries experience. Exfoliative cytology was used to study the cytological changes of buccal mucosal cells. Data was analysed using SPSS version 22. Student’s t-test, Fisher’s exact test and odd’s ration was used for comparison. p < 0.05 was considered statistically significant. Results: No significant differences were found between the groups with respect to proportion of subjects with gingivitis (p = 0.071), erosion (p = 0.085) and dental caries experience (p = 0.329). However, shisha smokers had poorer oral hygiene and more severe gingival inflammation as compared to non-smokers with p = 0.026 and p = 0.007 respectively. The odds of having atypical cells in oral mucosa among shisha smokers was 3.76 times higher than the non-smokers. Conclusion: The findings of our study showed that young shisha smokers had more atypical cells in oral mucosa as compared to their non-smoking counterparts. However, longitudinal studies are needed to affirm the findings of this study.

Sealants for preventing dental caries in primary teeth

BACKGROUND

Pit and fissure sealants are plastic materials that are used to seal deep pits and fissures on the occlusal surfaces of teeth, where decay occurs most often in children and adolescents. Deep pits and fissures can retain food debris and bacteria, making them difficult to clean, thereby causing them to be more susceptible to dental caries. The application of a pit and fissure sealant, a non-invasive preventive approach, can prevent dental caries by forming a protective barrier that reduces food entrapment and bacterial growth. Though moderate-certainty evidence shows that sealants are effective in preventing caries in permanent teeth, the effectiveness of applying pit and fissure sealants to primary teeth has yet to be established.

OBJECTIVES

To evaluate the effects of sealants compared to no sealant or a different sealant in preventing pit and fissure caries on the occlusal surfaces of primary molars in children and to report the adverse effects and the retention of different types of sealants.

SEARCH METHODS

An information specialist searched four bibliographic databases up to 11 February 2021 and used additional search methods to identify published, unpublished and ongoing studies. Review authors scanned the reference lists of included studies and relevant systematic reviews for further studies.

SELECTION CRITERIA

We included parallel-group and split-mouth randomised controlled trials (RCTs) that compared a sealant with no sealant, or different types of sealants, for the prevention of caries in primary molars, with no restriction on follow-up duration. We included studies in which co-interventions such as oral health preventive measures, oral health education or tooth brushing demonstrations were used, provided that the same adjunct was used with the intervention and comparator. We excluded studies with complex interventions for the prevention of dental caries in primary teeth such as preventive resin restorations, or studies that used sealants in cavitated carious lesions.

DATA COLLECTION AND ANALYSIS

Two review authors independently screened search results, extracted data and assessed risk of bias of included studies. We presented outcomes for the development of new carious lesions on occlusal surfaces of primary molars as odds ratios (OR) with 95% confidence intervals (CIs). Where studies were similar in clinical and methodological characteristics, we planned to pool effect estimates using a random-effects model where appropriate. We used GRADE methodology to assess the certainty of the evidence.

MAIN RESULTS

We included nine studies that randomised 1120 children who ranged in age from 18 months to eight years at the start of the study. One study compared fluoride-releasing resin-based sealant with no sealant (139 tooth pairs in 90 children); two studies compared glass ionomer-based sealant with no sealant (619 children); two studies compared glass ionomer-based sealant with resin-based sealant (278 tooth pairs in 200 children); two studies compared fluoride-releasing resin-based sealant with resin-based sealant (113 tooth pairs in 69 children); one study compared composite with fluoride-releasing resin-based sealant (40 tooth pairs in 40 children); and one study compared autopolymerised sealant with light polymerised sealant (52 tooth pairs in 52 children). Three studies evaluated the effects of sealants versus no sealant and provided data for our primary outcome. Due to differences in study design such as age of participants and duration of follow-up, we elected not to pool the data. At 24 months, there was insufficient evidence of a difference in the development of new caries lesions for the fluoride-releasing sealants or no treatment groups (Becker Balagtas odds ratio (BB OR) 0.76, 95% CI 0.41 to 1.42; 1 study, 85 children, 255 tooth surfaces). For glass ionomer-based sealants, the evidence was equivocal; one study found insufficient evidence of a difference at follow-up between 12 and 30 months (OR 0.97, 95% CI 0.63 to 1.49; 449 children), while another with 12-month follow-up found a large, beneficial effect of sealants (OR 0.03, 95% CI 0.01 to 0.15; 107 children). We judged the certainty of the evidence to be low, downgrading two levels in total for study limitations, imprecision and inconsistency. We included six trials randomising 411 children that directly compared different sealant materials, four of which (221 children) provided data for our primary outcome. Differences in age of the participants and duration of follow-up precluded pooling of the data. The incidence of development of new caries lesions was typically low across the different sealant types evaluated. We judged the certainty of the evidence to be low or very low for the outcome of caries incidence. Only one study assessed and reported adverse events, the nature of which was gag reflex while placing the sealant material.

AUTHORS' CONCLUSIONS

The certainty of the evidence for the comparisons and outcomes in this review was low or very low, reflecting the fragility and uncertainty of the evidence base. The volume of evidence for this review was limited, which typically included small studies where the number of events was low. The majority of studies in this review were of split-mouth design, an efficient study design for this research question; however, there were often shortcomings in the analysis and reporting of results that made synthesising the evidence difficult. An important omission from the included studies was the reporting of adverse events. Given the importance of prevention for maintaining good oral health, there exists an important evidence gap pertaining to the caries-preventive effect and retention of sealants in the primary dentition, which should be addressed through robust RCTs.

Synthesis and Incorporation of Quaternary Ammonium Silane Antimicrobial into Self-Crosslinked Type I Collagen Scaffold: A Hybrid Formulation for 3D Printing

Novel 3D-biomaterial scaffold is constructed having a combination of a new quaternary ammonium silane (k21) antimicrobial impregnated in 3D collagen printed scaffolds cross linked with Riboflavin in presence of d-alpha-tocopheryl poly(ethyleneglycol)-1000-succinate. Groups of "0.1% and 0.2% k21", and "0.1% and 0.2% Chlorhexidine (CHX)" are prepared. k21/CHX with neutralized collagen is printed with BioX. Riboflavin is photo-activated and examined using epifluorescence for Aggregatibacter actinomycetemcomitans (7-days). Collagen is examined using TEM and measured for porosity, and shape-fitting. Raman and tandem mass/solid-state are performed with molecular-docking and circular-dichroism. X-ray diffractions, rheological tests, contact angle, and ninhydrin assay are conducted. k21 samples demonstrated collagen aggregates while 0.1% CHX and 0.2% CHX showed irregularities. Porosity of control and "0.1% and 0.2% k21" scaffolds show no differences. Low contact angle, improved elastic-modulus, rigidity, and smaller strain in k21 groups are seen. Bacteria are reduced and strong organic intensities are seen in k21 scaffolds. Simulation shows hydrophobicity/electrostatic interaction. Crosslinking is observed in 0.2% CHX/79% and 0.2% k21/80%. Circular dichroism for k21 are suggestive of triple helix. XRD patterns appear at d = 5.97, 3.03, 2.78, 2.1, and 2.90 A°. 3D-printing of collagen impregnated with quaternary ammonium silane produces a promising scaffold with antimicrobial potency and structural stability.

Antibacterial and antibiofilm efficacy of k21-E in root canal disinfection

OBJECTIVES

The aim of the current project was to study the antimicrobial efficacy of a newly developed irrigant, k21/E against E. faecalis biofilm.

METHODS

Root canals were instrumented and randomly divided into the following groups: irrigation with saline, 6% NaOCl (sodium hypochlorite), 6% NaOCl+2% CHX (Chlorhexidine), 2% CHX, 0.5% k21/E (k21 - quaternary ammonium silane) and 1% k21/E. E. faecalis were grown (3-days) (1×10⁷CFU mL^-1), treated, and further cultured for 11-days. Specimens were subjected to SEM, confocal and Raman analysis and macrophage vesicles characterized along with effect of lipopolysaccharide treatment. 3T3 mouse-fibroblasts were cultured for alizarin-red with Sortase-A active sites and Schrödinger docking was performed. TEM analysis of root dentin substrate with matrix metalloproteinases profilometry was also included. A cytotoxic test analysis for cell viability was measured by absorbance of human dental pulp cells after exposure to different irrigant solutions for 24h. The test percentages have been highlighted in Table 1.

RESULTS

Among experimental groups, irrigation with 0.5% k21/E showed phase separation revealing significant bacterial reduction and lower phenylalanine 1003cm^-1 and Amide III 1245cm^-1 intensities. Damage was observed on bacterial cell membrane after use of k21/E. No difference in exosomes distribution between control and 0.5%k21/E was observed with less TNFα (*p<0.05) and preferential binding of SrtA. TEM images demonstrated integrated collagen fibers in control and 0.5%k21/E specimens and inner bacterial membrane damage after k21/E treatment. The k21 groups appeared to be biocompatible to the dental pulpal cells grown for 24h.

SIGNIFICANCE

Current investigations highlight potential advantages of 0.5% k21/E as irrigation solution for root canal disinfection.

Assessment of antimicrobial activity of different concentrations of Tinospora cordifolia against Streptococcus mutans: An in vitro study

Background:

The antimicrobial property of Tinospora cordifolia has been tested against a variety of microorganisms in the literature. The present study aimed to assess the antimicrobial activity of different concentrations of commercially available T. cordifolia powder against Streptococcus mutans.

Materials and Methods:

An in vitro study was undertaken in which extract of T. cordifolia was obtained using 100% ethanol by maceration. Seven different concentrations were prepared and tested against S. mutans in brain–heart infusion agar medium. Plates were incubated aerobically at 37°C for 48 h, and zone of inhibition was measured using Vernier caliper. 0.2% chlorhexidine and dimethylformamide were used as positive and negative controls respectively. The data were analysed by descriptive analytic tests.

Results:

The maximum antibacterial activity of T. cordifolia was observed with a volume of 40 μl at 2% concentration with a zone of inhibition of 19 mm. A 30 μl volume of 0.2% chlorhexidine showed a zone of inhibition of 28 mm, and no zone of inhibition was observed with dimethylformamide.

Conclusion:

Tinospora exhibited antimicrobial activity against S. mutans. However, it needs to be confirmed further with in vivo studies.

Surgical management of wide intrabony defect underlying midline diastema using Whale's tail flap technique: A Case Report

INTRODUCTION

Management of wide midline diastemas accompanying an underlying osseous defect is cumbersome which sometimes yields unpredictable results. However, regenerative therapy of these highly aesthetic zones using a Whale's tail flap technique obtains a maximum papilla fill after placement of the bone graft. This case report illustrated the utilisation of Whale's tail technique of flap for a large interdental defect.

CASE PRESENTATION

A young healthy 31-year-old male patient presented with maxillary midline diastema. Probing depth of 6 mm was also noted over the mesial aspect of the same teeth with localised osseous defect radiographically which lead to a diagnosis of localized chronic periodontitis in relation to those teeth. A Whale's tail technique flap for papilla preservation was performed together with a regenerative procedure using bone graft and GTR membrane.

DISCUSSION

Midline diastema is a common reported complaint in dentistry due to both aesthetic and functional reasons. Following the treatment, 12 months postoperatively, patient had a probing depth reduction of 3 mm and a gain in clinical attachment of 2 mm. The surgical technique allowed regeneration of wide intrabony defects involving the maxillary anterior teeth with notable interdental diastemas.

CONCLUSION

This lead to significant improvement of the hard and soft tissue contour as well as it recreated a functional reattachment which was documented up to 12 months postoperatively.

Root coverage of a wide anterior mucogingival defect with epithelial embossed connective tissue graft and its evaluation using root coverage esthetic scores

New and innovative surgical techniques are necessary to help the clinician ensure the best results and satisfy patient's expectations. One such periodontal problem that has been challenging to the dental practitioners and impacts the oral health quality of life of patients has been gingival recession. When present anteriorly where esthetics is a major concern, patient centric parameters too become paramount. Root coverage esthetic score (RES) evaluation helps to keep the patient outcomes in mind. This case reports the successful treatment of a wide anterior mucogingival defect using epithelial embossed connective tissue graft which was evaluated for the first time using RES.

Effect of dried sunflower seeds on incisal edge abrasion: A rare case report

Tooth surface loss (TSL) is a complex phenomenon characterized by the loss of hard tooth structure at various locations of the teeth, usually due to more than one factor. TSL due to abrasion can be significant in patients consuming coarse, abrasive diet. The present case reports an interesting incisal edge abrasion in a female patient, attributed to a particular dietary behavior of long-term consumption of sunflower seeds. All her family members and most of the people from her native place were also reported to have similar lesions by the patient. Larger epidemiological studies to assess the prevalence and severity of such abrasive lesions in geographic areas with this particular dietary habit need to be carried out so that people may be made aware and educated about alternative ways of eating sunflower seeds that will not cause any form of tooth wear.

Emergency Peripartum Hysterectomies at a District General Hospital in United Kingdom: 10-Year Review of Practice

Peripartum haemorrhage is an obstetric emergency which requires effective and timely management. A retrospective analysis was conducted at a single centre district hospital, over a 10-year period to describe factors that would lead to a peripartum hysterectomy. We sought to establish intraoperative and postoperative risks and review outcomes and complications associated with the procedure. A total of 29 cases (incidence 0.8 per 1000) were reviewed over 2001-2011. The mean parity was 1.8 and the mean maternal age was 33 years. Uterine atony was the most common indication for hysterectomy (12/29) followed by placenta praevia and accreta (4/29 and 5/29 cases, resp.). The commonest postoperative complications were sepsis and paralytic ileus. EPH most commonly occurs due to uterine atony but remains difficult to predict. Hospitals should continue to have robust systems and the necessary resources available to perform EPH where clinically indicated.

Evaluation of Interference of Cellular Phones on Electronic Apex Locators: An In Vitro Study

INTRODUCTION

Use of mobile phone has been prohibited in many hospitals to prevent interference with medical devices. Electromagnetic radiation emitted from cellular phones might interfere with electronic working length determination. The purpose of this in vitro study was to evaluate the effect of a smart phone (Samsung Galaxy Note Edge) on working length determination of electronic apex locators (EALs) Propex II and Rootor.

METHODS

Fifteen intact, non-carious single-rooted teeth were decoronated at the cementoenamel junction. Visually, working length was determined by using a #15 K-file under stereomicroscope (×20). The effect of cellular phones on electronic working length (EWL) was determined under 2 experimental settings: (1) in a closed room with poor signal strength and (2) in a polyclinic set up with good signal strength and 5 conditions: (1) electronically, without cellular phone in room; (2) electronically, with cellular phone in physical contact with EAL; (3) electronically, with mobile phone in physical contact with EAL and in calling mode for a period of 25 seconds; (4) electronically, mobile phone placed at a distance of 40 cm from the EAL; and (5) electronically, mobile phone placed at a distance of 40 cm and in calling mode for a period of 25 seconds. The EWL was measured 3 times per tooth under each condition. Stability of the readings was scored from 1 to 3: (1) good stability, (2) stable reading after 1 attempt, and (3) stable reading after 2 attempts. The data were compared by using analysis of variance.

RESULTS

The EWL measurements were not influenced by the presence of cellular phone and could be determined under all experimental conditions.

CONCLUSIONS

Within the limitations of this study, it can be concluded that mobile phones do not interfere with the EWL determination.

Multiple bony overgrowths in the mouth - report of two cases

Tori and exostoses are benign bony protuberances that arise from bone surfaces in the oral cavity. The etiology of these growths has been implicated as multifactorial, but no consensus has been reached so far. These painless overgrowths seldom present as a complaint in the dental office unless functional or esthetic complications set in, and there is a fear for cancer. Here we discuss two rare cases where bony overgrowths present in the mouth were extensive and multiple.

Testicular fluorine-18 fludeoxyglucose uptake on positron emission tomography CT in patients with lymphoma: clinical significance and management impact

OBJECTIVE

This is the first case series examining the role of fluorine-18 fludeoxyglucose ((18)F-FDG) positron emission tomography-CT (PET-CT) in the diagnosis of lymphoma, and its impact on the clinical management of patients with secondary testicular involvement. This study explores the clinical significance of abnormal testicular uptake, maximum standardized uptake values and the diagnostic value of the CT component in PET-CT scans of these patients.

METHODS

The case notes and PET scans of 12 patients with diagnosis of lymphoma that were reported to have abnormal (18)F-FDG uptake in the testes were examined. Case notes were reviewed for the underlying diagnosis, indication for the scan and its effect on the management decision.

RESULTS

12 patients demonstrated abnormal (18)F-FDG uptake on the PET-CT scans (mean age, 63 years; range, 37-82 years). Seven patients were diagnosed with testicular lymphoma. Six out of the seven (86%) patients received additional intrathecal chemotherapy in addition to their systemic chemotherapy, and one patient had testicular radiotherapy.

CONCLUSION

This study establishes the importance of identifying and reporting abnormal (18)F-FDG uptake in the testes on PET-CT in patients with lymphoma. (18)F-FDG PET-CT is superior to conventional imaging in identifying testicular lymphoma and has significant management impact. It also emphasizes the importance of incorporating the testes as part of the scan coverage.

ADVANCES IN KNOWLEDGE

The appearances of testicular lymphoma on (18)F-FDG PET-CT can be variable and abnormal testicular uptake warrants further investigations and confirmation. FDG PET-CT is an important tool and can be used in addition to conventional imaging in the identification of testicular lymphoma.

Thermal burn of palate in an elderly diabetic patient

BACKGROUND

Burns of the oral mucosa may be caused by thermal, mechanical, chemical, electrical or radiation injury. Clinically, these burns can produce localised or diffuse areas of tissue damage depending on the severity and extent of the insult. Most oral thermal burns produce erosions or ulcers on the palate or tongue.

MATERIALS AND METHODS

A case of palatal burn in a 66-year-old diabetic patient caused by drinking hot cereal is presented. The role of diabetes in causing oral mucosal dysesthesia that predisposed the occurrence of this burn is also discussed.

CONCLUSION

Insensate palatal burn as a rare complication of diabetes mellitus is reported here. With the disease being more widespread now, its potential oral complications will be seen with increasing frequency.

Pharmacodynamics of florfenicol for calf pneumonia pathogens

The antimicrobial properties of florfenicol were investigated for the bovine respiratory tract pathogens, Mannheimia haemolytica and Pasteurella multocida. Three in vitro indices of efficacy and potency were determined; minimum inhibitory concentration (MIC), minimum bactericidal concentration (MBC) and in vitro time-kill curves for six pathogenic strains of each organism. Each was monitored in two matrices, Mueller Hinton broth (MHB) and calf serum. MBC:MIC ratios were low, 1.8 : 1 for M haemolytica in both MHB and serum and 2.4 : 1 and 2.1 : 1 for P multocida in MHB and serum, respectively. The killing action of florfenicol had the characteristics of concentration dependency against M haemolytica and codependency (on time and concentration) against P multocida. Modelling of the time-kill data after 24 hours exposure was undertaken to quantify three levels of activity for the ratio, area under concentration-time curve over 24 hours (AUC24h)/MIC; bacteriostatic action (no change in bacterial count), 3log10 reduction and 4log10 reduction in bacterial count. Mean AUC24h/MIC values for P multocida in MHB (and serum) were 22.0 (23.3) hour, 34.5 (39.9) hour and 45.8 (50.4) hour, respectively. Similar numerical values were obtained for M haemolytica. For both bacterial species, interstrain variability was low; coefficients of variation ( per cent) in serum for 3log10 and 4log10 reductions in count were, respectively, 14.3 and 24.1 for P multocida and 7.8 and 11.4 for M haemolytica. These data form a rational basis for dosage selection for treatment of calf pneumonia caused by M haemolytica or P multocida.

Primary adenoid cystic carcinoma of the bronchus in a female teenager

Primary adenoid cystic carcinoma (ACC) of the lung is an extremely rare malignant lung neoplasm. ACC of salivary glands of the head and neck, lachrymal glands, breast, skin, vulva and trachea have been frequently reported disease patterns in the literature, but it is unique to see this rare lung tumour in a patient as young as 14 years old. No double blind placebo, multicentre treatment data are available. Surgery is considered as the cornerstone of the treatment. Prognosis is variable and adjuvant radiotherapy has been found beneficial for prolonged survival. Our report of primary lung ACC in a young girl is a complex case due to young age, a different way of presentation and staging on diagnosis. It has been a quite challenging clinical scenario for the multidisciplinary lung cancer treating team involved in the clinical care. Prognosis remains unpredictable and uncertain despite the best present day evidence-based treatment.

Ineffectiveness of nickel in augmenting the hepatotoxicity in protein deficient rats

This study was designed to determine the toxic effects of nickel sulfate on the biochemical and elemental profile of liver in protein deficient rats. Nickel sulfate in the dose of 800mg/l in drinking water was administrated to Sprauge Dawley (S.D) normal control as well as protein deficient rats for a total duration of eight weeks. The effects of nickel treatment and protein deficiency when given separately and in combination were studied on rat liver marker enzymes like Alkaline phosphatase (ALP),Glutamate oxaloacetate transaminase (GOT), Glutamate pyruvate transaminase (GPT) and also on the status of essential elements in rat liver. Protein deficient, Ni treated as well as combined protein deficient and nickel treated rats showed significant reductions in the body weight and hepatic protein contents as compared to normal control rats. Hepatic alkaline phosphatase activity and alanine aminotransferase showed a significant elevation in rats subjected to protein deficiency, nickel treatment and combined protein deficiency and nickel treatment. As regards to hepatic levels of aspartate aminotransferase a significant elevation was observed in protein deficient and nickel treated protein deficient animals. Nickel administration to normal and protein deficient rats has resulted in a significant increase in concentrations of nickel, phosphorus and sulfur in liver tissue. The concentration of zinc and copper in liver tissue decreased significantly in protein deficient, nickel treated and nickel treated protein deficient animals. Tissue iron concentrations were found to be decreased in protein deficient animals, but the concentrations of iron got elevated significantly in nickel treated and nickel treated protein deficient animals. It has been observed that selenium got decreased significantly in protein deficient, nickel treated and nickel treated protein deficient animals when compared to normal animals. The elevation of selenium in nickel treated protein deficient animals was also significantly higher when compared to protein deficient animals.

Protective effects of zinc on oxidative stress enzymes in liver of protein deficient rats

This study was designed to evaluate the protective effects of zinc on the liver activities of antioxidant enzymes in protein-deficient rats. Zinc sulfate at a dose level of 227 mg/l in drinking water was administrated to Sprague Dawley normal control as well as to protein-deficient rats for a total duration of eight weeks. The effects of zinc treatment and protein deficiency alone as well as combined were studied on rat liver antioxidant enzymes which included catalase, glutathione peroxidase (GPX), glutathione reductase (GR), superoxide dismutase (SOD), and glutathione S-transferase (GST). Protein deficiency in normal rats resulted in a significant increase in hepatic lipid peroxidation and in catalase, Gpx, GR and GST activity. A significant inhibition in the levels of SOD activity and reduced glutathione (GSH) was observed following protein deficiency in normal rats. Zn treatment to protein deficient animals lowered lipid peroxidation and catalase, Gpx and GST activities, and also resulted in a significant elevation in the levels of GSH and SOD activity. The concentration of zinc decreased significantly in protein deficient animals but returned to normal levels when zinc was administered.

Tissue chamber model of acute inflammation in farm animal species

A tissue chamber model of acute inflammation for use in comparative studies in calves, sheep, goats and pigs has been established and validated. Tissue chambers were prepared from silicon rubber tubing, of inner diameter 12.7 mm, length 115 mm and volume 15 ml, with 10 holes, each of 6mm diameter, at each end. In each animal two or four chambers were inserted at subcutaneous sites. Six weeks after implantation an acute inflammatory reaction in a single cage was generated by the intracaveal injection of 0.5 ml of 1% carrageenan solution. Serial samples of exudate (injected chamber), transudate (non-injected chamber) and blood were collected for measurement of exudate and transudate leucocyte count, prostaglandin (PG)E(2) concentration in exudate and serum thromboxane (Tx)B(2) concentration. In addition, skin temperature changes over exudate and transudate chambers were recorded. In all four species, carrageenan induced an acute inflammatory response, indicated by increases to peak values followed by return towards baseline in skin temperature, leucocyte count and PGE(2) concentration. For each of these variables in calves, sheep and goats the increases were significantly greater for exudate than for transudate. The degree of intra-species variation in each variable was acceptable. Marked inter-species differences were recorded: skin temperature rise was greatest in calves and least in sheep and goats; exudate PGE(2) concentration was increased in the order sheep>goat>pig>calf; serum TxB(2) concentration was increased in the order calf>goat>sheep>pig and exudate leucocyte count was increased to a greater extent in the pig than in the three ruminant species. The model has advantages over some previously described tissue chamber models of inflammation and will be suitable for use in comparative studies of inflammatory mechanisms and the pharmacokinetics and pharmacodynamics of anti-inflammatory drugs.

Bronchopleural fistula after pneumonectomy

BACKGROUND

Bronchopleural fistula (BPF) is an infrequent but life-threatening complication after lung resection. The incidence of BPF reported in the literature varies between 0 and 15%.

AIM

To evaluate the incidence of BPF after pneumonectomy for primary lung cancer in a single practice using a single technique.

METHODS

Hospital records of patients who underwent pneumonectomy from 1 January 1988 to 1 October 1998 were reviewed retrospectively. The bronchial stump was closed using a uniform hand suture technique. There was a total of 157 patients, including 118 males and 39 females with a mean age of 64 years (range 37-78). Sixty-two patients (39.5%) had a right pneumonectomy.

RESULTS

Three patients developed BPF (1.9%). All occurred within seven days of the operation. Two of the three patients died. Ventilation for more than 24 hours was found to be the only significant risk factor for the development of BPF (p < 0.001).

CONCLUSIONS

Hand suture closure of bronchial stump after pneumonectomy is a safe, reproducible and inexpensive technique, and a low incidence of BPF can be achieved.