Basic taste processing recruits bilateral anteroventral and middle dorsal insulae: An activation likelihood estimation meta-analysis of fMRI studies

BACKGROUND AND PURPOSE

Numerous task-based functional magnetic resonance imaging (fMRI) studies have reported the locations of basic taste representations in the human brain, but they usually employed a limited number of subjects (<20) with different methodologies and stimuli. Moreover, the reported brain regions were sometimes inconsistent. Thus, we aimed at performing a meta-analysis of the published data to identify locations consistently activated across studies, and performed a connectivity analysis to reveal how these taste processing regions connect with other brain regions.

MATERIALS AND METHODS

A meta-analysis was performed based on 34 experiments, with 238 total participants in 16 studies, to establish the activation likelihood estimation (ALE) of taste-mediated regional activation. Meta-analytic connectivity modeling (MACM) and data stored in BrainMap database were employed to reveal the functional connectivity of the regions identified by ALE with other brain regions, across all types of experiments that caused activation among healthy subjects.

RESULTS

ALE identified nine activated clusters in bilateral anteroventral and middle dorsal insulae, bilateral thalamus and caudate, bilateral pre-/postcentral gyrus, and right hippocampus. The concurrence between studies was moderate, with at best 38% of experiments contributed to the significant clusters activated by taste stimulation. Sweet taste was the predominant contributing taste. MACM revealed that at least 50% of the nine clusters coactivated with the middle cingulate cortex, medial frontal gyrus, inferior parietal lobule, and putamen.

CONCLUSION

Results suggested that fMRI studies have reported reproducible patterns of activations across studies. The basic taste stimulations resulted in activations in a mostly bilateral network. Moreover, they were connected with cognitive and emotional relevant brain regions.

Randomised clinical trial: rifaximin versus placebo for the treatment of functional dyspepsia

BACKGROUND

Gut dysbiosis may contribute to pain and bloating in patients with functional gastrointestinal disease.

AIMS

To determine if treatment with rifaximin would improve the symptoms of functional dyspepsia in Chinese patients in a double-blinded, randomised, placebo-controlled trial.

METHODS

Consecutive subjects with a diagnosis of functional dyspepsia as per the Rome III criteria were randomised to receive rifaximin 400 mg or placebo, all taken three times daily for 2 weeks. The investigators and study subjects were blinded to the treatment allocation. Subjects were followed up for 8 weeks. The primary end point was adequate relief of global dyspeptic symptoms (GDS). Secondary endpoints were relief of individual dyspeptic symptoms.

RESULTS

Eighty-six subjects were recruited. At week 8, there were significantly more subjects in the rifaximin than in the placebo group who experienced adequate relief of GDS (78% vs. 52%, P = 0.02). A trend favouring rifaximin group was also noted in the preceding 4 weeks. Rifaximin was also superior to placebo in providing adequate relief of belching and post-prandial fullness/bloating (PPF) in subjects at week 4. Subgroup analysis revealed that female subjects had more significant response to rifaximin treatment (adequate relief of GDS at week 4: 76% vs. 42%, P = 0.006; week 8: 79% vs. 47%, P = 0.008), as well as improvements in their belching and PPF at week 4. The incidences of adverse effects were similar in both groups.

CONCLUSIONS

Treatment with 2 weeks of rifaximin led to adequate relief of global dyspeptic symptoms, belching and post-prandial fullness/bloating in subjects with functional dyspepsia. The difference was more marked in females. (clinicaltrials.org NCT01643083).

Effects of nucleoside analogue prescription for hepatitis B on the incidence of liver cancer in Hong Kong: a territory-wide ecological study

BACKGROUND

The temporal relationship between nucleoside analogue therapy for chronic hepatitis B (CHB) and liver cancer development has not been evaluated at a population level.

AIM

To investigate the impact of nucleoside analogue prescription on liver cancer incidence in a CHB-prevalent region.

METHODS

We obtained territory-wide nucleoside analogue prescription data from 1999, when nucleoside analogue was first available in Hong Kong, to 2012 and the population-based liver cancer incidence data from 1990 to 2012. We compared the liver cancer incidences from 1990 to 1998 and 1999 to 2012 with adjustment for local hepatitis B surface antigen seroprevalence.

RESULTS

Nucleoside analogue prescription patient headcount increased from 2006 per year in 1999 to 26 411 in 2012. Prescription volume in 2012 was highest among 55-64 years (30.3%), higher than 65-74 years (13.0%) and ≥75 years (5.8%). Age-standardised liver cancer incidence 1999-2012 decreased by 1.88%/year (95% CI 3.34% to 0.42%/year). NA therapy was associated with decline in age-adjusted liver cancer incidence (2.7 per 100 000 persons, P < 0.001, 95% CI 1.4-4.0 per 100 000 persons). Fifty-five to sixty-four years age group had the most significant decline (men: 24.0 per 100 000 persons, P = 0.001, 95% CI 11.4-36.6 per 100 000 persons; women: 8.5 per 100 000 persons, P = 0.009, 95% CI 2.3-14.6 per 100 000 persons). No significant association was noted in age groups 65-74 years and ≥75 years (both P > 0.05).

CONCLUSIONS

Nucleoside analogue prescription was associated with a reduction of overall liver cancer incidence in a CHB-prevalent region. The lack of association among individuals of ≥65 years was consistent with the low nucleoside analogue prescription volume in elderly patients, mitigating the impact of CHB treatment on liver cancer.

Adjunctive use of modified Yunu-Jian in the non-surgical treatment of male smokers with chronic periodontitis: a randomized double-blind, placebo-controlled clinical trial

Background

Yunu-Jian (YJ) is a Chinese medicine (CM) heat purging formula, which is used to reduce wei huo (stomach-heat, SH) and enrich shen yin (kidney-yin, KY). This formula is also commonly used to manage diabetes mellitus and gum/oral inflammation. The activity of YJ can be modified or refined by the addition of other CM herbs and/or minor changes to one of its five key ingredients. The aim of this study was to evaluate the adjunctive use of modified YJ (mYJ) or YJ containing additional osteoblast-stimulating and inflammation-modulating CM herbs in the non-surgical periodontal treatment of smokers with chronic periodontitis in a randomized, double-blind, prospective, placebo-controlled study.

Methods

Healthy adult male smokers with untreated chronic periodontitis who showed CM syndrome of SH and KY deficiency (KYD) whilst attending a dental teaching hospital from October to December, 2005, were invited to participate in a randomized double-blind, placebo-controlled clinical trial. The trial itself involved the once-daily oral administration of a placebo or mYJ for 3 months as an adjunct to non-surgical periodontal therapy. Several periodontal parameters, including radiographic alveolar bone density, were measured by computer-assisted densitometric image analysis (CADIA) on selected sites, and CM signs of SH and KYD were followed from their baseline values to various time points up to 12 months or the end of study.

Results

Twenty-five smokers (consumed 25.0 ± 15.3 smoking-pack years, ranged 7.5–80; aged 46.3 ± 6.8 years) with periodontitis and SH and KYD were recruited (Placebo, n = 14; mYJ, n = 11). All of the participants showed good tolerance towards the CM recipe. All of the periodontal parameters had improved after 12-month follow-up, and no statistically significant differences were detected between the control group and test group, except for the higher CADIA values observed compared with the baseline at 12 months for test sites (P = 0.025). 4/3/3 test vs 14/13/13 control participants had persisting SH and KYD at 6, 9 and 12 months (P < 0.001), respectively.

Conclusions

The adjunctive use of mYJ preserved the post-treatment increases in the radiographic alveolar bone density at the study sites and led to an overall improvement in SH and KYD compared with the controls.

Trial registration HKU Clinical Trial Register, HKCTR-1848 (www.hkuctr.com/Study/Show/3acbf983831244d29d50b543540bf6e9)

Electronic supplementary material

The online version of this article (doi:10.1186/s13020-016-0111-z) contains supplementary material, which is available to authorized users.

Low-dose azathioprine is effective in maintaining remission in steroid-dependent ulcerative colitis: results from a territory-wide Chinese population-based IBD registry

BACKGROUND

Whether low-dose azathioprine (AZA) is effective in maintaining remission in patients with steroid-dependent ulcerative colitis (UC) remains unclear. We assessed the efficacy and safety of low-dose AZA in a Chinese population with UC.

METHODS

We identified steroid-dependent UC patients in clinical remission on AZA maintenance therapy from a territory-wide IBD Registry. Standard- and low-dose AZA were defined as at least 2 mg/kg/day and less than 2 mg/kg/day, respectively. Relapse rates were analyzed by Kaplan-Meier analysis and compared using log-rank test.

RESULTS

Among 1226 UC patients, 128 (53% male, median duration on AZA 44 months) were included. Median maintenance AZA dose was 1.3 mg/kg/day. 97.7% of the patients were on concomitant oral 5-aminosalicylic acid. Cumulative relapse-free rates in patients on standard-dose and low-dose AZA were 71.2%, 52.8% and 45.2%, and 71.8%, 55.3% and 46.2% at 12, 24 and 36 months, respectively (p = 0.871). Relapse rate within 12 months was higher in patients who withdrew compared with those who maintained on AZA (52.6% versus 29.4%; p = 0.045). Mean corpuscular volume increased after AZA therapy in both of the low-dose [median (interquartile range, IQR): 88.2 (81.4-92.2) versus 95.1 (90.1-100.9) fl, p < 0.001] and standard-dose subgroups [median (IQR) 86.8 (76.9-89.9) versus 94.7 (85.9-99.7) fl, p < 0.001]. Leukopenia occurred in 21.1% of the patients. Patients on standard dose had a higher risk for leukopenia than those on low-dose AZA [odds ratio (OR) 3.9, 95% CI 1.9-8.2, p < 0.001].

CONCLUSIONS

In the Chinese population, low-dose AZA is effective for maintaining remission in steroid-dependent UC patients. Standard-dose AZA was associated with more than threefold increased risk of leukopenia.

Natural History of Elderly-onset Ulcerative Colitis: Results from a Territory-wide Inflammatory Bowel Disease Registry

BACKGROUND AND AIMS

Data on the natural history of elderly-onset ulcerative colitis [UC] are limited. We aimed to investigate clinical features and outcomes of patients with elderly-onset UC.

METHODS

Patients with a confirmed diagnosis of UC between 1981 and 2013, from 13 hospitals within a territory-wide Hong Kong Inflammatory Bowel Disease Registry, were included. Clinical features and outcomes of elderly-onset patients, defined as age ≥ 60 years at diagnosis, were compared with those of non-elderly-onset disease [< 60 years at diagnosis].

RESULTS

We identified 1225 patients, of whom 12.8% [157/1225; 56.1% male] had elderly-onset UC. Median duration of follow-up was 11 years [interquartile range, 6-16 years]. Age-specific incidence of elderly-onset UC increased from 0.1 per 100000 persons before 1991 to 1.3 per 100000 persons after 2010. There were more ex-smokers [32.2% vs. 12.2%, p < 0.001] and higher proportion of comorbidities [p < 0.001] in elderly-onset than non-elderly-onset patients. Disease extent, corticosteroids, immunosuppressants use, and colectomy rates were similar between the two groups. Elderly-onset disease was an independent risk factor for cytomegalovirus infection [odds ratio 2.9, 95% confidence interval 1.6-5.2, p < 0.001]. More elderly-onset patients had Clostridium difficile infection [11.0% vs. 5.4%, p = 0.007], hospitalisation for UC exacerbation [50.6% vs. 41.8%, p = 0.037], colorectal cancer [3.2% vs. 0.9%, p = 0.033], all-cause mortality [7.0% vs. 1.0%, p < 0.001], and UC-related mortality [1.9% vs. 0.2%, p = 0.017] than non-elderly-onset patients.

CONCLUSIONS

Elderly-onset UC patients are increasing in number. These patients have higher risk of opportunistic infections, hospitalisation, colorectal cancer, and mortality than non-elderly-onset patients. Management and therapeutic strategies in this special group need careful attention.

Asia-Pacific consensus statements on Crohn's disease. Part 2: Management

The Asia Pacific Working Group on Inflammatory Bowel Disease was established in Cebu, Philippines, at the Asia Pacific Digestive Week conference in 2006 under the auspices of the Asian Pacific Association of Gastroenterology (APAGE) with the goal of developing best management practices, coordinating research and raising awareness of IBD in the region. The consensus group previously published recommendations for the diagnosis and management of ulcerative colitis (UC) with specific relevance to the Asia-Pacific region. The present consensus statements were developed following a similar process to address the epidemiology, diagnosis and management of Crohn's disease (CD). The goals of these statements are to pool the pertinent literature specifically highlighting relevant data and conditions in the Asia-Pacific region relating to the economy, health systems, background infectious diseases, differential diagnoses and treatment availability. It does not intend to be all-comprehensive and future revisions are likely to be required in this ever-changing field.

Asia Pacific Consensus Statements on Crohn's disease. Part 1: Definition, diagnosis, and epidemiology: (Asia Pacific Crohn's Disease Consensus--Part 1)

Inflammatory bowel disease (IBD) was previously thought to be rare in Asia, but emerging data indicate rising incidence and prevalence of IBD in the region. The Asia Pacific Working Group on Inflammatory Bowel Disease was established in Cebu, Philippines, at the Asia Pacific Digestive Week conference in 2006 under the auspices of the Asian Pacific Association of Gastroenterology with the goal of developing best management practices, coordinating research, and raising awareness of IBD in the region. The consensus group previously published recommendations for the diagnosis and management of ulcerative colitis with specific relevance to the Asia-Pacific region. The present consensus statements were developed following a similar process to address the epidemiology, diagnosis, and management of Crohn's disease. The goals of these statements are to pool the pertinent literature specifically highlighting relevant data and conditions in the Asia-Pacific region relating to the economy, health systems, background infectious diseases, differential diagnoses, and treatment availability. It does not intend to be all comprehensive and future revisions are likely to be required in this ever-changing field.

Association of periodontal and cardiovascular diseases: South-Asian studies 2001-2012

Large proportion of Asian populations have moderate to severe periodontal disease and a substantial number are anticipated to be at high risk of cardiovascular diseases (CVD). This study reviews epidemiology and association of periodontal and CVDs from the South-Asian region. Observational studies and clinical trials published during January 2001-December 2012 focusing association between periodontitis and CVDs in South-Asian countries were retrieved from various databases and studied. Current evidence suggests that both periodontal and CVDs are globally prevalent and show an increasing trend in developing countries. Global data on epidemiology and association of periodontal and CVDs are predominantly from the developed world; whereas Asia with 60% of the world's population lacks substantial scientific data on the link between periodontal and CVDs. During the search period, 14 studies (5 clinical trials, 9 case-controls) were reported in literature from South-Asia; 100% of clinical trials and 77% case-control studies have reported a significant association between the oral/periodontal parameters and CVD. Epidemiological and clinical studies from South-Asia validate the global evidence on association of periodontal disease with CVDs. However, there is a need for meticulous research for public health and scientific perspective of the Periodontal and CVDs from South-Asia.

Systematic review with meta-analysis: the association between the use of calcium channel blockers and gastrointestinal bleeding

BACKGROUND

Due to their potential anti-platelet effect, it is suggested that calcium channel blockers (CCBs) are associated with gastrointestinal bleeding (GIB). However, results from previous studies are conflicting.

AIM

To conduct a systematic review and meta-analysis of randomised controlled trials (RCTs) and observational studies to clarify the association between CCBs and GIB.

METHODS

We conducted a systematic search of PubMed, EMBASE, Cochrane library and Trial Register databases up to January 2015. Studies that evaluated exposure to CCBs reporting GIB outcomes were included in the meta-analysis. The inverse variance method with random effects model was used to calculate the pooled estimates.

RESULTS

Seventeen studies (four RCTs, eleven case-control and two cohort studies) were included in the meta-analysis. The summary risk ratio (RR) for GIB was 1.17 (95% CI 1.01-1.36) for CCB users vs. non-users. Subgroup analysis showed that CCB use was associated with a moderately higher risk of lower GIB (RR = 1.83, 95% CI 1.17-2.84) but not upper GIB. However, data from four RCTs did not support association between CCBs and GIB (RR = 0.93, 95% CI 0.82-1.05). Subgroup analyses further showed that the increased risk of GIB among CCB users was only observed in studies that failed to adjust for prior history of GIB (RR = 1.67, 95% CI 1.34-2.08) or use of anti-ulcer drugs (RR = 1.40, 95% CI 1.19-1.65).

CONCLUSION

Our meta-analysis showed a marginal association between calcium channel blocker use and the risk of gastrointestinal bleeding. This association is of dubious clinical significance, as the effects of different comparators or adjustment for confounding factors render this association nonsignificant.

Hospital Authority audit of the outcome of endoscopic resection of superficial upper gastro-intestinal lesions in Hong Kong

OBJECTIVES

To review the short-term outcome of endoscopic resection of superficial upper gastro-intestinal lesions in Hong Kong.

DESIGN

Historical cohort study.

SETTING

All Hospital Authority hospitals in Hong Kong.

PATIENTS

This was a multicentre retrospective study of all patients who underwent endoscopic resection of superficial upper gastro-intestinal lesions between January 2010 and June 2013 in all government-funded hospitals in Hong Kong.

MAIN OUTCOME MEASURES

Indication of the procedures, peri-procedural and procedural parameters, oncological outcomes, morbidity, and mortality.

RESULTS

During the study period, 187 lesions in 168 patients were resected. Endoscopic mucosal resection was performed in 34 (18.2%) lesions and endoscopic submucosal dissection in 153 (81.8%) lesions. The mean size of the lesions was 2.6 (standard deviation, 1.8) cm. The 30-day morbidity rate was 14.4%, and perforations and severe bleeding occurred in 4.3% and 3.2% of the patients, respectively. Among patients who had dysplasia or carcinoma, R0 resection was achieved in 78% and the piecemeal resection rate was 11.8%. Lateral margin involvement was 14% and vertical margin involvement was 8%. Local recurrence occurred in 9% of patients and 15% had residual disease. The 2-year overall survival rate and disease-specific survival rate was 90.6% and 100%, respectively.

CONCLUSION

Endoscopic mucosal resection and endoscopic submucosal dissection were introduced in low-to-moderate-volume hospitals with acceptable morbidity rates. The short-term survival was excellent. However, other oncological outcomes were higher than those observed in high-volume centres and more secondary procedures were required.

Role of periodontal disease in bisphosphonate-related osteonecrosis of the jaws in ovariectomized rats

OBJECTIVE

This study aimed to investigate the role of progressive periodontal disease in inducing bisphosphonate-related osteonecrosis of the jaws (BRONJ) using an ovariectomized (OVX) rat model mimicking human intracortical remodeling process.

MATERIALS AND METHODS

Thirty 12-week-old Spraque-Dawly (SD) female rats were randomly assigned into two groups. All rats underwent bilateral ovariectomy. Six weeks after surgery, zoledronic acid (ZA) or vehicle control was administered intraperitoneally for 12 weeks. On the same day of injection, a cotton ligature was placed subgingivally around the first left lower molar to induce periodontitis. All animals were sacrificed 12 weeks after injection. The entire mandibles were harvested for micro-computed tomography (micro-CT) and histological examinations.

RESULTS

Micro-CT examination showed that ligature placement caused significant alveolar bone loss both in ZA (0.63 ± 0.13 vs. 0.38 ± 0.06 mm, P < 0.001) and in control (0.88 ± 0.19 vs. 0.40 ± 0.06 mm, P < 0.001) groups. Whereas in the ZA group, bone loss was attenuated compared with the control group (P < 0.01); the bone mineral density in the ZA group (1.00 ± 0.02 g/cm(3)) was significantly higher than that in vehicle control group (0.96 ± 0.03 g/cm(3), P < 0.001). Histological examination found necrotic bone tissue with extensive, empty lacunae in two of 15 rats in ZA group, but in none of the control group.

CONCLUSION

Bisphosphonates inhibit alveolar bone resorption in progressive periodontal disease, which might benefit the management of periodontitis, but increase the risk of developing BRONJ.

Primary sensory neurons regulate Toll-like receptor-4-dependent activity of glial cells in dorsal root ganglia

Toll-like receptor-4 (TLR4) has been identified in primary sensory neurons, both in vivo and in vitro, but is reportedly absent from satellite glial cells (SGCs). Herein we reveal that, in rat dorsal root ganglia (DRG), SGCs do express TLR4 but this expression is inhibited by direct contact with neurons. Thus, TLR4 mRNA and protein is strongly up-regulated in isolated DRG glial cells in the absence of neurons. Lipopolysaccharide (LPS) increased cyclooxygenase-2 (COX-2) and tumor necrosis factor-α (TNFα) mRNA expression with greater efficacy in DRG glial cell cultures than in mixed DRG cell cultures containing TLR4-positive neurons. Using an insert co-culture system, we have shown that neuronal inhibition of glial cell TLR4 is likely to be dependent on cell-cell contact rather than diffusible factors from neurons. LPS stimulated prostaglandin E2 (PGE2) production from DRG glial cells in a TLR4- and COX-2-dependent manner. In addition, exogenous PGE2 potentiated LPS-stimulated COX-2 mRNA while inhibiting TNFα mRNA expression by DRG cells, suggestive of a complex regulatory system to control inflammation within the DRG. In addition to LPS, conditioned medium from heat-shocked DRG neurons also increased COX-2 mRNA expression in DRG glial cells in a partially TLR4-dependent manner. We therefore hypothesize that neuronal suppression of glial TLR4 activity is a protective mechanism to prevent uncontrolled inflammation within the DRG. Under conditions where DRG neuronal viability is compromised, DRG glial cells become responsive to PAMPs (pathogen-associated molecular patterns) and DAMPs (danger-associated molecular patterns) and generate a range of classical inflammatory responses.

Differential expression of Toll-like receptor 4 in healthy and diseased human gingiva

BACKGROUND AND OBJECTIVE

Lipopolysaccharide (LPS)-mediated signaling in host cells involves Toll-like receptor 4 (TLR4) accessory molecules, including LPS-binding protein (LBP), cluster of differentiation 14 (CD14) and lymphocyte antigen 96 (MD-2). However, expression of these innate defense molecules in various compartments of the human periodontium is unclear. The aim of this study was to investigate the expression profile of TLR4 in human gingiva.

MATERIAL AND METHODS

Human gingival biopsies were collected from healthy gingival or chronic periodontitis tissue. Primary gingival keratinocytes and fibroblasts were cultured. Immunohistochemical analysis for TLR4 was performed. Transcripts of TLR4, MD-2, CD14 and LBP, and their protein products, were examined using RT-PCR, immunoprecipitation and immunoblotting. The interactions between these molecules in keratinocytes and fibroblasts were investigated by co-immunoprecipitation.

RESULTS

TLR4 immunoreactivity was found in healthy gingival epithelium and periodontitis tissue, and appeared to be lower in junctional epithelium ( p ≤ 0.01). Fibroblasts and inflammatory cells stained more strongly for TLR4 in diseased periodontal tissues (p < 0.001). Three TLR4 splicing variants, two MD-2 splicing variants and one CD14 mRNA were expressed by gingival keratinocytes and fibroblasts. Expression of TLR4, CD14 and MD-2 proteins was detected in keratinocytes and fibroblasts in vitro. TLR4 protein from gingival keratinocytes and fibroblasts could be co-immunoprecipitated with CD14 or MD-2, suggesting an association between the related molecules in vivo. LBP transcript was detected in gingival biopsies, but not in primary cultures of gingival keratinocytes or fibroblasts.

CONCLUSION

TLR4, CD14 and MD-2, but not LBP, are expressed in human gingival keratinocytes and fibroblasts. The TLR4 expression level in the junctional epithelium appeared to be lowest within the periodontal epithelial barrier.

Use of biologics for inflammatory bowel disease in Hong Kong: consensus statement

OBJECTIVE; With the increasing use of biologics in patients with inflammatory bowel disease, the Hong Kong IBD Society developed a set of consensus statements intended to serve as local recommendations for clinicians about the appropriate use of biologics for treating inflammatory bowel disease.

PARTICIPANTS

The consensus meeting was held on 9 July 2011 in Hong Kong. Draft consensus statements were developed by core members of the Hong Kong IBD Society, including local gastroenterologists and colorectal surgeons experienced in managing patients with inflammatory bowel disease.

EVIDENCE

Published literature and conference proceedings on the use of biologics in management of inflammatory bowel disease, and guidelines and consensus issued by different international and regional societies on recommendations for biologics in inflammatory bowel disease patients were reviewed.

CONSENSUS PROCESS

Four core members of the consensus group drafted 19 consensus statements through the modified Delphi process. The statements were first circulated among a clinical expert panel of 15 members for review and comments, and were finalised at the consensus meeting through a voting session. A consensus statement was accepted if at least 80% of the participants voted "accepted completely or "accepted with some reservation".

CONCLUSIONS

Nineteen consensus statements about inflammatory bowel disease were generated by the clinical expert panel meeting. The statements were divided into four parts which covered: (1) epidemiology of the disease in Hong Kong; (2) treatment of the disease with biologics; (3) screening and contra-indications pertaining to biologics; and (4) patient monitoring after use of biologics. The current statements are the first to describe the appropriate use of biologics in the management of inflammatory bowel disease in Hong Kong, with an aim to provide guidance for local clinical practice.

Prevalence and diversity of Synergistetes taxa in periodontal health and disease

BACKGROUND AND OBJECTIVE

Members of the phylum Synergistetes have previously been identified within periodontitis subgingival plaque and are considered putative periodontopathogens. This study compared the diversity of subginigval Synergistetes in a cohort of subjects with periodontitis (n = 10) vs. periodontitis-free controls (n = 10).

MATERIAL AND METHODS

Pooled subgingival plaque samples from all deep periodontal pockets or all sulci were collected from the periodontitis and periodontitis-free subjects, respectively. Bacterial 16S rRNA genes were PCR-amplified from purified subgingival plaque DNA using a Synergistetes 'selective' primer set. PCR products were cloned and sequenced to analyze the prevalence and diversity of Synergistetes operational taxonomic units (OTUs) present in plaque samples of both subject groups.

RESULTS

A total of 1030 non-chimeric 16S rRNA clones were obtained, of which 162 corresponded to members of the phylum Synergistetes. A significantly larger number of Synergistetes clones were obtained from periodontitis subgingival plaque than from periodontitis-free controls (25.4% vs. 5.9%, p < 0.001). All Synergistetes clones corresponded to cluster A oral Synergistetes, and fell into 31 OTUs (99% sequence identity cut-off). Twenty-nine Synergistetes OTUs were detected in the periodontitis group while eight were detected in the periodontitis-free group (p < 0.001). Five Synergistetes OTUs; including one OTU corresponding to the recently-characterized species Fretibacterium fastidiosum, were more prevalent in the periodontitis subjects (p < 0.05).

CONCLUSION

OTUs belonging to oral Synergistetes cluster A were more readily detectable and were more diverse in subgingival plaque from periodontitis subjects compared with periodontitis-free controls. Specific Synergistetes OTUs appear to be associated with periodontitis.

A pale Chinese boy with recurrent painful digital swelling

Thalassaemia is the most common haemoglobinopathy in the Chinese population. However, recurrent painful digital swelling is not a typical manifestation of this well-known hereditary condition. We describe a case of co-inheritance of beta-thalassaemia and sickle cell trait in a Chinese family and a child who suffered from sickle cell/beta-thalassaemia with recurrent dactylitis. This report highlights awareness of this rare condition in the Chinese population, since acute manifestations can be life-threatening and mimic other emergency conditions. Prompt management can prevent further complications and avoid unnecessary interventions due to delay in diagnosis. A detailed family history and examination of the patient's peripheral blood smear is crucial to reach a correct diagnosis.

Genetic polymorphism studies in periodontitis and Fcγ receptors

Periodontitis is a complex chronic subgingival plaque-induced inflammatory disease influenced by multiple factors, including genetics, behavior and the environment. Many genetic association studies have been conducted in periodontology. One of the most extensively investigated gene families is the Fcγ receptor gene family, which plays a key role in regulating host immune responses to bacteria. Unlike other genetic polymorphisms reported in periodontology, most Fcγ receptor polymorphisms reported not only have established biological functions but are reported to associate with other autoimmune diseases, such as rheumatoid arthritis and systemic lupus erythematosus. There are, however, few recent reviews summarizing the association of this gene family with periodontitis. This article critically reviews the current understanding of genetic polymorphism studies in periodontitis, then summarizes the research status of Fcγ receptor polymorphisms and periodontitis and also of other genes involved in the regulatory network of Fcγ receptors, with special reference to their anticipated biological roles. Moreover, some possible future research directions in the related area are discussed.

SNPs of Fc-gamma receptor genes and chronic periodontitis

Genetic polymorphisms of host defense genes might increase risk for periodontitis. This case-control study investigated whether 102 single-nucleotide polymorphisms (SNPs) in Fc gamma receptor (FCGR) genes are associated with chronic periodontitis. Cases were 190 Hong Kong Chinese patients with severe chronic periodontitis, and there were 169 periodontitis-free individuals as controls. Genotype CC and allele C of rs445509 (p < 0.0001, OR = 0.30) of FCGR3A were significantly more prevalent among control individuals than among cases, after adjustment for age, sex, and smoking. Smoking was significantly associated with chronic periodontitis (p = 0.003, OR = 3.35). Within the limitations of this study, SNP rs445509 of FCGR3A seem to be negatively associated, while smoking was positively associated, with severe chronic periodontitis among Hong Kong Chinese.

The Asia-Pacific consensus on ulcerative colitis

Inflammatory bowel disease (IBD) is increasing in many parts of the Asia-Pacific region. There is a need to improve the awareness of IBD and develop diagnostic and management recommendations relevant to the region. This evidence-based consensus focuses on the definition, epidemiology and management of ulcerative colitis (UC) in Asia. A multi-disciplinary group developed the consensus statements, reviewed the relevant literature, and voted on them anonymously using the Delphi method. The finalized statements were reviewed to determine the level of consensus, evidence quality and strength of recommendation. Infectious colitis must be excluded prior to diagnosing UC. Typical histology and macroscopic extent of the disease seen in the West is found in the Asia-Pacific region. Ulcerative colitis is increasing in many parts of Asia with gender distribution and age of diagnosis similar to the West. Extra-intestinal manifestations including primary sclerosing cholangitis are rarer than in the West. Clinical stratification of disease severity guides management. In Japan, leukocytapheresis is a treatment option. Access to biologic agents remains limited due to high cost and concern over opportunistic infections. The high endemic rates of hepatitis B virus infection require stringent screening before initiating immune-suppressive agents. Vaccination and prophylactic therapies should be initiated on a case-by-case basis and in accordance with local practice. Colorectal cancer complicates chronic colitis. A recent increase in UC is reported in the Asia-Pacific region. These consensus statements aim to improve the recognition of UC and assist clinicians in its management with particular relevance to the region.