Improved CaP Nanoparticles for Nucleic Acid and Protein Delivery to Neural Primary Cultures and Stem Cells

Efficiently delivering exogenous materials into primary neurons and neural stem cells (NSCs) has long been a challenge in neurobiology. Existing methods have struggled with complex protocols, unreliable reproducibility, high immunogenicity, and cytotoxicity, causing a huge conundrum and hindering in-depth analyses. Here, we establish a cutting-edge method for transfecting primary neurons and NSCs, named teleofection, by a two-step process to enhance the formation of biocompatible calcium phosphate (CaP) nanoparticles. Teleofection enables both nucleic acid and protein transfection into primary neurons and NSCs, eliminating the need for specialized skills and equipment. It can easily fine-tune transfection efficiency by adjusting the incubation time and nanoparticle quantity, catering to various experimental requirements. Teleofection's versatility allows for the delivery of different cargos into the same cell culture, whether simultaneously or sequentially. This flexibility proves invaluable for long-term studies, enabling the monitoring of neural development and synapse plasticity. Moreover, teleofection ensures the consistent and robust expression of delivered genes, facilitating molecular and biochemical investigations. Teleofection represents a significant advancement in neurobiology, which has promise to transcend the limitations of current gene delivery methods. It offers a user-friendly, cost-effective, and reproducible approach for researchers, potentially revolutionizing our understanding of brain function and development.

Identification and characterisation of de novo germline structural variants in two commercial pig lines using trio-based whole genome sequencing

BACKGROUND

De novo mutations arising in the germline are a source of genetic variation and their discovery broadens our understanding of genetic disorders and evolutionary patterns. Although the number of de novo single nucleotide variants (dnSNVs) has been studied in a number of species, relatively little is known about the occurrence of de novo structural variants (dnSVs). In this study, we investigated 37 deeply sequenced pig trios from two commercial lines to identify dnSVs present in the offspring. The identified dnSVs were characterised by identifying their parent of origin, their functional annotations and characterizing sequence homology at the breakpoints.

RESULTS

We identified four swine germline dnSVs, all located in intronic regions of protein-coding genes. Our conservative, first estimate of the swine germline dnSV rate is 0.108 (95% CI 0.038-0.255) per generation (one dnSV per nine offspring), detected using short-read sequencing. Two detected dnSVs are clusters of mutations. Mutation cluster 1 contains a de novo duplication, a dnSNV and a de novo deletion. Mutation cluster 2 contains a de novo deletion and three de novo duplications, of which one is inverted. Mutation cluster 2 is 25 kb in size, whereas mutation cluster 1 (197 bp) and the other two individual dnSVs (64 and 573 bp) are smaller. Only mutation cluster 2 could be phased and is located on the paternal haplotype. Mutation cluster 2 originates from both micro-homology as well as non-homology mutation mechanisms, where mutation cluster 1 and the other two dnSVs are caused by mutation mechanisms lacking sequence homology. The 64 bp deletion and mutation cluster 1 were validated through PCR. Lastly, the 64 bp deletion and the 573 bp duplication were validated in sequenced offspring of probands with three generations of sequence data.

CONCLUSIONS

Our estimate of 0.108 dnSVs per generation in the swine germline is conservative, due to our small sample size and restricted possibilities of dnSV detection from short-read sequencing. The current study highlights the complexity of dnSVs and shows the potential of breeding programs for pigs and livestock species in general, to provide a suitable population structure for identification and characterisation of dnSVs.

Efficacy of Silkworm Pupae Extract on Muscle Strength and Mass in Middle-Aged and Older Individuals: A Randomized, Double-Blind, Placebo-Controlled Trial

OBJECTIVES

We investigated the efficacy and safety of silkworm pupae extract (SWP) consumption for 12 weeks on muscle mass and strength in middle-aged and older individuals with relatively low skeletal muscle mass who do regular low-intensity exercise.

DESIGN

A randomized double-blinded placebo-controlled trial.

PARTICIPANTS

The study was conducted with 54 participants with relatively low skeletal muscle mass (SMM) (64.4 ± 6.1 years; body mass index, 23.8 ± 2.4 kg/m2).

INTERVENTION AND MEASUREMENTS

Participants were randomly assigned to one of two groups: 1000 mg of SWP/day plus regular exercise (SWP group, n=27) or placebo plus regular exercise (placebo group, n=27). All participants were required to engage in 30-60 minutes/day of walking for ≥3 days/week for 12 weeks. The primary outcome was knee extension/flexion strength (Nm), measured at the velocity of 60°/s. Secondary outcomes included body composition, biomarkers (creatine kinase and creatinine), handgrip strength, and quality of life questionnaire.

RESULTS

Both the intention-to-treat (ITT) and per-protocol (PP) analyses revealed no significant impact of SWP on knee strength compared to the placebo group over 12 weeks. On the other hand, the SWP group had significantly greater increases in right-handgrip strength by 1.94 kg (95% CI: 0.08-3.79; p = 0.041) and left-handgrip strength by 1.83 kg (0.25-3.41; p = 0.024) compared to the placebo group in the ITT population, after 12 weeks. Moreover, in the PP population, the SWP group revealed an even greater increase in right-handgrip strength by 2.07 kg (0.15-3. 98; p = 0.035) and left-handgrip strength by 2.21 kg (0.60-3.83; p = 0.008) for the 12-week period. However, this study resulted in a failure to detect significant differences in the body composition, biomarkers, quality of life questionnaire, physical activity, and caloric intake between the groups. None of the participants in the SWP group experienced any significant adverse events. In the placebo group, two participants experienced urticaria and allergic side effects, leading to their withdrawal from the study and two exhibited elevated levels of liver enzyme and increased diastolic blood pressure, respectively at 12 weeks.

CONCLUSION

SWP, in addition to low-intensity exercise, may enhance handgrip strengths in middle-aged and older adults with relatively lower SMM. Future studies need to use a large sample size over longer periods to validate our findings. This trial was registered at clinicaltrials.gov as NCT04994054.

SOX9+ enthesis cells are associated with spinal ankylosis in ankylosing spondylitis

OBJECTIVE

Although cartilage degeneration and invasion of the subchondral bone plate in entheseal lesion has been considered to consequently lead bony ankylosis in ankylosing spondylitis (AS), no evident mechanisms are known.

DESIGN

To identify histopathological and physiological changes in enthesitis-related ankylosis in AS, we performed molecular characterization of transcription factors and surface markers, and transcriptome analysis with human tissues. Entheseal tissue containing subchondral bone was obtained from the facet joints of 9 patients with AS and 10 disease controls, and assessed by using differential staining techniques. Enthesis cells were isolated, characterized, stimulated with TNF and/or IL-17A, and analysed by cell-based experimental tools.

RESULTS

We found diffusely distributed granular tissue and cartilage in the subchondral bone in AS. Co-expression of SOX9, a specific transcription factor in cartilage, and matrix metalloproteinase 13 (MMP13) was found in the granular tissues within the subchondral bone from AS patients. Intriguingly, SOX9 expression was significantly higher in AS enthesis cells than controls and correlated with TNFR1 and IL-17RA expressions, which is important for high reactivity to TNF and IL-17A cytokines. Co-stimulation by TNF and IL-17A resulted in accelerated mineralization/calcification features, and increased OCN expression in AS enthesis cells. Furthermore, SOX9 overexpression in enthesis leads to promoting mineralization feature by TNF and IL-17A stimuli. Finally, OCN expression is elevated in the destructive enthesis of advanced AS.

CONCLUSION

These findings provide insight into the links between inflammation and the mineralization of entheseal tissue as the initiation of spinal ankylosis, emphasizing the importance of SOX9⁺ enthesis cells.

Effect of the use of earplugs and eye masks on the quality of sleep after major abdominal surgery: a randomised controlled trial

Significant sleep disturbance can occur following major abdominal surgery. We aimed to evaluate the effectiveness of earplugs and eye masks in improving sleep quality and patient satisfaction, reducing nursing demands and in the incidence of delirium in patients after major abdominal surgery. We conducted a randomised controlled trial in 100 patients undergoing major abdominal surgery. We randomly allocated participants to sleep with or without earplugs and eye masks on postoperative days 1-3. The primary outcome measure was sleep quality as measured by the Richards-Campbell Sleep Questionnaire. Secondary outcomes were patient satisfaction, frequency of nursing demand and incidence of delirium measured by the Neelon and Champagne Confusion Scale. Median (IQR [range]) sleep scores were 64 (38-74 [0-100] and 60 (44-82 [18-100]) for the control and intervention groups, respectively (p = 0.310). Age and Pittsburgh Sleep Quality Index scores were found to be significant factors affecting sleep quality. There were no differences in patient satisfaction, reduction in frequency of nursing demands or incidence of delirium on postoperative days 1-3 after major abdominal surgery. The compliance rate in the intervention group was 60-65%. This study has demonstrated that the use of earplugs and eye masks did not contribute to improvements in sleep quality. Of note, sleep quality was moderate, with higher age and worse baseline sleep quality contributing to worse sleep scores. More studies are needed to investigate interventions to improve sleep quality after major abdominal surgery.

Hyperpolyploidization of hepatocyte initiates preneoplastic lesion formation in the liver

Hepatocellular carcinoma (HCC) is the most predominant primary malignancy in the liver. Genotoxic and genetic models have revealed that HCC cells are derived from hepatocytes, but where the critical region for tumor foci emergence is and how this transformation occurs are still unclear. Here, hyperpolyploidization of hepatocytes around the centrilobular (CL) region is demonstrated to be closely linked with the development of HCC cells after diethylnitrosamine treatment. We identify the CL region as a dominant lobule for accumulation of hyperpolyploid hepatocytes and preneoplastic tumor foci formation. We also demonstrate that upregulation of Aurkb plays a critical role in promoting hyperpolyploidization. Increase of AURKB phosphorylation is detected on the midbody during cytokinesis, causing abscission failure and hyperpolyploidization. Pharmacological inhibition of AURKB dramatically reduces nucleus size and tumor foci number surrounding the CL region in diethylnitrosamine-treated liver. Our work reveals an intimate molecular link between pathological hyperpolyploidy of CL hepatocytes and transformation into HCC cells.

Dual-Specificity Phosphatase 15 (DUSP15) Modulates Notch Signaling by Enhancing the Stability of Notch Protein

Dual-specificity phosphatases (DUSPs) comprise a unique group of enzymes that dephosphorylate signaling proteins at both phospho-serine/threonine and phospho-tyrosine residues. Since Notch signaling is an essential pathway for neuronal cell fate determination and development that is also upregulated in Alzheimer's disease tissues, we sought to explore whether and how DUSPs may impact Notch processing. Our results show that overexpression of DUSP15 concomitantly and dose-dependently increased the steady-state levels of recombinant Notch (extracellular domain-truncated Notch, NotchΔE) protein and its cleaved product, Notch intracellular domain (NICD). The overall ratio of NotchΔE to NICD was unchanged by overexpression of DUSP15, suggesting that the effect is independent of γ-secretase. Interestingly, overexpression of DUSP15 also dose-dependently increased phosphorylated ERK1/2. Phosphorylated ERK1/2 is known to be positively correlated with Notch protein level, and we found that DUSP15-mediated regulation of Notch was dependent on ERK1/2 activity. Together, our findings reveal the existence of a previously unidentified DUSP15-ERK1/2-Notch signaling axis, which could potentially play a role in neuronal differentiation and neurological disease.

Let-7 derived from endometrial extracellular vesicles is an important inducer of embryonic diapause in mice

Embryonic diapause is a maternally controlled phenomenon. The molecule controlling the onset of the phenomenon is unknown. We demonstrated that overexpression of microRNA let-7a or incubation with let-7g-enriched extracellular vesicles from endometrial epithelial cells prolonged the in vitro survival of mouse blastocysts, which developed into live pups after having been transferred to foster mothers. Similar to in vivo dormant blastocysts, let-7-induced dormant blastocysts exhibited low level of proliferation, apoptosis, and nutrient metabolism. Let-7 suppressed c-myc/mTORC1 and mTORC2 signaling to induce embryonic diapause. It also inhibited ODC1 expression reducing biosynthesis of polyamines, which are known to reactivate dormant embryos. Furthermore, the overexpression of let-7 blocked trophoblast differentiation and implantation potential of human embryo surrogates, and prolonged survival of human blastocysts in vitro, supporting the idea that embryonic diapause was an evolutionary conserved phenomenon. In conclusion, let-7 is the main factor inducing embryonic diapause.

Phosphatidylinositol-4-phosphate 5-kinase type 1α attenuates Aβ production by promoting non-amyloidogenic processing of amyloid precursor protein

Alzheimer's disease (AD) is characterized by a chronic decline in cognitive function and is pathologically typified by cerebral deposition of amyloid-β peptide (Aβ). The production of Aβ is mediated by sequential proteolysis of amyloid precursor protein (APP) by β- and γ-secretases, and has been implicated as the essential determinant of AD pathology. Previous studies have demonstrated that the level of phosphatidylinositol-4,5-bisphosphate [PI(4,5)P2] in the membrane may potentially modulate Aβ production. Given that PI(4,5)P2 is produced by type 1 phosphatidylinositol-4-phosphate 5-kinases (PIP5Ks), we sought to determine whether the level of PIP5K type Iα (PIP5K1A) can affect production of Aβ by modulating the lipid composition of the membrane. Using a HEK-derived cell line that constitutively expresses yellow fluorescent protein-tagged APP (APP-YFP), we demonstrated that overexpression of PIP5K1A results in significant enhancement of non-amyloidogenic APP processing and a concomitant suppression of the amyloidogenic pathway, leading to a marked decrease in secreted Aβ. Consistently, cells overexpressing PIP5K1A exhibited a significant redistribution of APP-YFP from endosomal compartments to the cell surface. Our findings suggest that PIP5K1A may play a critical role in governing Aβ production by modulating membrane distribution of APP, and as such, the pathway may be a valuable therapeutic target for AD.

Association of antimicrobial resistance and gut microbiota composition in human and non-human primates at an urban ecotourism site

Background

The rise of nature-based ecotourism in the past decade has introduced unprecedented challenges in managing the increasing interaction between humans and animals. The potential transmission of antibiotic resistant microbes between humans and non-human primate populations is a concern due to their genetic similarity. Malaysia is well known for hotspots of wildlife diversity where non-human primates like monkeys and orangutans have become popular tourist attractions. In this study, we assessed the prevalence of antimicrobial resistant Staphylococcus aureus, Enterococcus species, and other Enterobacteriaceae in the faeces of human (HS) and two non-human primates (NHP) in Malaysia, the Long-tailed macaque (Macaca fascicularis, MF) and Silvered leaf monkey (Trachypithecus cristatus, TC). In addition, the faecal bacterial composition was profiled to evaluate the potential association between antibiotic resistant profiles and composition of gut microbiota.

Results

We tested the isolated bacteria using a selection of antibiotics. The results showed that both the number of antibiotic resistant strains and resistance level were higher in humans than NHPs. Overall, the composition of gut microbiome and pattern of antibiotic resistance showed that there was higher similarity between MF and TC, the two NHPs, than with HS. In addition, samples with higher levels of antibiotic resistance showed lower bacterial richness. Homo sapiens had the lowest bacterial diversity and yet it had higher abundance of Bacteroides. In contrast, NHPs displayed higher bacterial richness and greater prevalence of Firmicutes such as Ruminococceae and Oscillospira.

Conclusion

Higher antibiotic susceptibility in NHPs is likely related to low direct exposure to antibiotics. The lack of resistance may also suggest limited antimicrobial resistance transmission between humans and NHP. Nonetheless, continued monitoring over a long period will help mitigate the risk of anthropozoonosis and zooanthroponosis.

Genetic profiles of transcriptomic clusters of childhood asthma determine specific severe subtype

BACKGROUND

Previous studies have defined transcriptomic subtypes of adult asthma using samples of induced sputum and bronchial epithelium; however, those procedures are not readily applicable in the clinic, especially for childhood asthma.

OBJECTIVE

We aim to dissect the transcriptomic clusters of childhood asthma using highly variably expressed genes of peripheral blood mononuclear cells (PBMC) among patients.

METHODS

Gene expression of PBMC from 133 asthmatic children and 11 healthy controls was measured with Illumina microarrays. We applied the k-means clustering algorithm of 2048 genes to assign asthmatic children into clusters. Genes with differential expression between asthma clusters and healthy controls were used to investigate whether they could identify severe asthma of children and adults.

RESULTS

We identified 3 asthma clusters with distinct inflammatory profiles in peripheral blood. Cluster 1 had the highest eosinophil count. Cluster 2 showed lower counts of both eosinophils and neutrophils. Cluster 3 had the highest neutrophil count and the poorest treatment control. Compared with other patients, Cluster 3 exhibited a unique gene expression pattern which was associated with changes in the glucocorticoid signalling and activation of the T helper 1/T helper 17 (T_H 1/T_H 17) immune pathways. In the validation studies, an 84-gene signature could identify severe asthma in children on leucocytes, as well as severe asthma in adults on CD8⁺ T cells.

CONCLUSIONS AND CLINICAL RELEVANCE

Gene expression profiling of PBMC is useful for the identification of T_H 1/T_H 17-mediated asthma with poor treatment control. PBMC and CD8⁺ T cells could be important targets for the investigation and identification of severe asthma.

Molecular detection of human adenovirus among hospitalized patients with lower respiratory tract infection in Hospital Sungai Buloh, Malaysia

Human adenovirus (HAdV) is one of the common pathogens that are responsible for a wide variety of infectious diseases. There are about 54 different adenovirus serotypes that are responsible for respiratory infections in humans. The prevalence of lower respiratory tract infection (LRTI) - associated with HAdV varies throughout different regions. The prevalence of HAdV in Malaysia is rarely investigated and reported despite severity of infection worldwide. This study was undertaken to identify the HAdV types associated with lower respiratory tract infection (LRTI) in Hospital Sungai Buloh, Malaysia between April 2013 until January 2014, a total of 210 specimens were collected from patients hospitalized with LRTI. Human adenovirus was detected using polymerase chain reaction (PCR). The positive products were sequenced and phylogenetic analysis of the virus was performed. Eighteen of 210 specimens (8.57%) were positive with HAdV infection. Based on the phylogenetic analysis study, HAdV-7 strains were the most common serotype with 11 cases, followed by HAdV-1, HAdV-2 and HAdV-4 with 2 cases each and one case of HAdV-5. The HAdV strains in this study were closely related to strains in Singapore and India. In this study, HAdV infection from LRTI patients in Hospital Sungai Buloh Malaysia were caused by different types of adenovirus mainly HAdV-7. This study will become a reference for further epidemiological study in this country.

Rapid adiposity growth increases risks of new-onset asthma and airway inflammation in children

BACKGROUND/OBJECTIVES

We aim to (1) examine the influence of long-term adiposity status/short-term adiposity changes on asthma with high or low fractional exhaled nitric oxide (Fe_NO), and (2) to determine the differences in long-term adiposity status/short-term adiposity changes on atopy, airway inflammation and pulmonary function.

SUBJECTS/METHODS

We recruited 2450 fourth- to sixth-grade children from the nationwide Taiwan Children Health Study. Data regarding various adiposity indicators, atopic status, pulmonary function tests and asthma outcomes were collected annually. New-onset asthma was stratified by airway inflammation status using Fe_NO. The generalized estimating equation was used for analyzing longitudinal relationships between long-term adiposity status/short-term adiposity changes and new-onset asthma. Individual adiposity growth slopes were obtained using a hierarchical linear model to establish the relationships between short-term adiposity changes and asthma among children with high airway inflammation.

RESULTS

We found long-term adiposity status predicted childhood asthma with low Fe_NO, whereas short-term adiposity changes may increase risks of childhood asthma with high Fe_NO. Long-term adiposity status reduced pulmonary function, whereas short-term adiposity increase were associated with atopic diseases and airway inflammation.

CONCLUSIONS

Obesity-induced asthma could be mediated by high or low airway inflammation, depending on the velocity of increase in adiposity. Rapid adiposity growth may increase risks of childhood asthma and airway inflammation.

Hyperglycemia impedes definitive endoderm differentiation of human embryonic stem cells by modulating histone methylation patterns

Exposure to maternal diabetes during fetal growth is a risk factor for the development of type II diabetes (T2D) in later life. Discovery of the mechanisms involved in this association should provide valuable background for therapeutic treatments. Early embryogenesis involves epigenetic changes including histone modifications. The bivalent histone methylation marks H3K4me3 and H3K27me3 are important for regulating key developmental genes during early fetal pancreas specification. We hypothesized that maternal hyperglycemia disrupted early pancreas development through changes in histone bivalency. A human embryonic stem cell line (VAL3) was used as the cell model for studying the effects of hyperglycemia upon differentiation into definitive endoderm (DE), an early stage of the pancreatic lineage. Hyperglycemic conditions significantly down-regulated the expression levels of DE markers SOX17, FOXA2, CXCR4 and EOMES during differentiation. This was associated with retention of the repressive histone methylation mark H3K27me3 on their promoters under hyperglycemic conditions. The disruption of histone methylation patterns was observed as early as the mesendoderm stage, with Wnt/β-catenin signaling being suppressed during hyperglycemia. Treatment with Wnt/β-catenin signaling activator CHIR-99021 restored the expression levels and chromatin methylation status of DE markers, even in a hyperglycemic environment. The disruption of DE development was also found in mouse embryos at day 7.5 post coitum from diabetic mothers. Furthermore, disruption of DE differentiation in VAL3 cells led to subsequent impairment in pancreatic progenitor formation. Thus, early exposure to hyperglycemic conditions hinders DE development with a possible relationship to the later impairment of pancreas specification.

Health impacts of Facebook usage and mobile texting among undergraduate dental students: it's time to understand the difference between usage and an excessive use

BACKGROUND

Facebook and mobile texting are prevalent in the lives of almost every student. However, little is known about the relationship between Facebook usage or mobile texting and their impacts on health amongst undergraduate dental students. In this study, excessive Facebook use and excessive mobile texting were studied as they relate to impacts on health.

MATERIALS AND METHODS

A cross-sectional study was conducted at a private university in Malaysia. A total of 188 undergraduate dental students were interviewed using a pre-tested and self-rated questionnaire. Data collected from participants were analysed using SPSS version 18.0. Chi-square test, Fisher's exact test and multiple logistic regression analyses were applied to study the relationship between explanatory variables and excessive Facebook use and excessive mobile texting.

RESULTS

The prevalence of excessive Facebook use and excessive mobile texting amongst undergraduate dental students was found to be 33.2% and 33.0%, respectively. According to a multivariate analysis, texting habits, such as the presence of daytime sleepiness after texting late at night (aOR = 2.682, 95% CI = 1.142-6.301) and the presence of anxious feelings if students failed to receive a timely response (aOR = 3.819, 95% CI = 1.580-9.230), were determined to be significant predictors of excessive mobile texting. Excessive Facebook use was found to be significantly related to three variables as follows: fewer numbers of close friends (aOR = 2.275, 95% CI = 1.057-4.898), the checking of updates on the Facebook walls of their friends (aOR = 2.582, 95% CI = 1.189-5.605) and the absence of active and vigorous feelings during Facebook use (aOR = 3.401, 95% CI = 1.233-9.434).

CONCLUSIONS

Approximately one-third of undergraduate dental students in this study experienced excessive Facebook use and/or excessive mobile texting. Health education and promotion should be instituted to create awareness, whilst students should be advised to practise self-control with respect to both mobile texting and Facebook usage.

The Forkhead box transcription factor FOXM1 is required for the maintenance of cell proliferation and protection against oxidative stress in human embryonic stem cells

Human embryonic stem cells (hESCs) exhibit unique cell cycle structure, self-renewal and pluripotency. The Forkhead box transcription factor M1 (FOXM1) is critically required for the maintenance of pluripotency in mouse embryonic stem cells and mouse embryonal carcinoma cells, but its role in hESCs remains unclear. Here, we show that FOXM1 expression was enriched in undifferentiated hESCs and was regulated in a cell cycle-dependent manner with peak levels detected at the G2/M phase. Expression of FOXM1 did not correlate with OCT4 and NANOG during in vitro differentiation of hESCs. Importantly, knockdown of FOXM1 expression led to aberrant cell cycle distribution with impairment in mitotic progression but showed no profound effect on the undifferentiated state. Interestingly, FOXM1 depletion sensitized hESCs to oxidative stress. Moreover, genome-wide analysis of FOXM1 targets by ChIP-seq identified genes important for M phase including CCNB1 and CDK1, which were subsequently confirmed by ChIP and RNA interference analyses. Further peak set comparison against a differentiating hESC line and a cancer cell line revealed a substantial difference in the genomic binding profile of FOXM1 in hESCs. Taken together, our findings provide the first evidence to support FOXM1 as an important regulator of cell cycle progression and defense against oxidative stress in hESCs.

Prevalence of Psychiatric Morbidity in Chinese Subjects with Knee Osteoarthritis in a Hong Kong Orthopaedic Clinic

OBJECTIVES

To identify the prevalence and associated factors of psychiatric morbidities and to evaluate the effectiveness of the Hospital Anxiety and Depression Scale (HADS) in screening for psychiatric morbidity in patients with knee osteoarthritis in a local orthopaedic clinic.

METHODS

A cross-sectional study was conducted from October 2013 to June 2014 to examine patients with knee osteoarthritis at a specialist orthopaedic clinic. They were evaluated for psychiatric diagnoses using the Structured Clinical Interview for the DSM-IV Axis I Disorders (SCID-I). Socio-demographic and clinical characteristics were compared between patients with and without psychiatric morbidity. Patients were also assessed using the HADS with accuracy compared with the psychiatric diagnoses made by the SCID-I.

RESULTS

Of the 115 patients, 39% had current psychiatric disorders. Logistic regression analysis revealed that limitation of physical activity, perceived absence of confidant, a history of psychiatric illness, and follow-up in orthopaedic clinic for ≥ 5 years were independent factors associated with psychiatric disorders.

CONCLUSIONS

The prevalence of psychiatric morbidity in patients with knee osteoarthritis was significant. Recognition of independent associated factors can aid in early identification and intervention in patients who are at risk of developing psychiatric morbidity. The HADS is a useful means to screen for psychiatric morbidity in these patients.

Is locking plate fixation a better option than casting for distal radius fracture in elderly people?

OBJECTIVES

To compare the outcomes of locking plate fixation versus casting for displaced distal radius fracture with unstable fracture pattern in active Chinese elderly people.

DESIGN

Historical cohort study.

SETTING

Orthopaedic ward and clinic at Tseung Kwan O Hospital, Hong Kong.

PATIENTS

Between 1 May 2010 and 31 October 2013, 57 Chinese elderly people aged 61 to 80 years were treated either operatively with locking plate fixation (n=26) or conservatively with cast immobilisation (n=31) for unstable displaced distal radius fracture.

MAIN OUTCOME MEASURES

Clinical, radiological, and functional outcomes were assessed at 9 to 12 months after treatment.

RESULTS

The functional outcome (based on the quick Disabilities of the Arm, Shoulder and Hand score) was significantly better in the locking plate fixation group than in the cast immobilisation group, while clinical and radiological outcomes were comparable with those in other similar studies.

CONCLUSIONS

Locking plate fixation resulted in better functional outcome for displaced distal radius fracture with unstable fracture pattern in active Chinese elderly people aged 61 to 80 years. Further prospective study with long-term follow-up is recommended.

Role of high resolution ultrasound in ulnar nerve neuropathy

AIM

This study was conducted to measure the cross sectional area (CSA) of the ulnar nerve (UN) in the cubital tunnel and to evaluate the role of high-resolution ultrasonography in the diagnosis of ulnar nerve neuropathy (UNN).

MATERIALS AND METHODS

This was a cross sectional study with 64 arms from 32 patients (34 neuropathic, 30 nonneuropathic). Diagnosis was confirmed by nerve conduction study and electromyography. The ulnar nerves were evaluated with 15MHz small footprint linear array transducer. The ulnar nerve CSA was measured at three levels with arm extended: at medial epicondyle (ME), 5cm proximal and 5cm distal to ME. Results from the neuropathic and nonneuropathic arms were compared. Independent T-tests and Pearson correlation tests were used. P value of less than 0.05 was considered significant.

RESULTS

Mean CSA values for the UN at levels 5cm proximal to ME, ME and 5cm distal to ME were 0.055, 0.109, 0.045 cm(2) respectively in the neuropathic group and 0.049, 0.075, 0.042 cm2 respectively in the non-neuropathic group. The CSA of the UN at the ME level was significantly larger in the neuropathic group, with p value of 0.005. However, there was no statistical difference between the groups at 5cm proximal and distal to the ME, with p values of 0.10 and 0.35 respectively.

CONCLUSION

There is significant difference in CSA values of the UN at ME between the neuropathic and non-neuropathic groups with mean CSA value above the predetermined 0.10cm(2) cut-off point. High-resolution ultrasonography is therefore useful to diagnose and follow up cases of elbow UNN.

A case of acute kidney injury by near-drowning

Acute kidney injury following immersion or near-drowning is rarely described and no data from Malaysia have been found. We report a case of acute kidney injury following a near-drowning event. A 20-year-old man who recovered from near-drowning in a swimming pool 5 days earlier presented to our clinic with abdominal pain, anorexia, nausea and polyuria. Dipstick urinalysis showed a trace of blood. The serum creatinine level was 10-fold higher than the normal range. A bedside ultrasound showed features suggestive of acute tubular necrosis. He is then referred to the hospital with the diagnosis of acute kidney injury with the possibility of acute tubular necrosis secondary to near-drowning. We suggest that any patient presenting after immersion or near-drowning to be should assessed for potential acute kidney injury.

Gender difference of childhood overweight and obesity in predicting the risk of incident asthma: a systematic review and meta-analysis

The aims of our meta-analysis were (i) to quantify the predictability of childhood overweight and obesity on the risk of incident asthma; and (ii) to evaluate the gender difference on this relationship. The selection criteria included prospective cohort paediatric studies which use age- and sex-specific body mass index (BMI) as a measure of childhood overweight and the primary outcome of incident asthma. A total of 1,027 studies were initially identified through online database searches, and finally 6 studies met the inclusion criteria. The combined result of reported relative risk from the 6 included studies revealed that overweight children conferred increased risks of incident asthma as compared with non-overweight children (relative risk, 1.19; 95% confidence interval [CI], 1.03-1.37). The relationship was further elevated for obesity vs. non-obesity (relative risk, 2.02; 95% CI, 1.16-3.50). A dose-responsiveness of elevated BMI on asthma incidence was observed (P for trend, 0.004). Obese boys had a significantly larger effect than obese girls (relative risk, boys: 2.47; 95% CI, 1.57-3.87; girls: 1.25; 95% CI, 0.51-3.03), with significant dose-dependent effect. Proposed mechanisms of gender difference could be through pulmonary mechanics, sleep disordered breathing and leptin. Further research might be needed to better understand the exact mechanism of gender difference on the obesity-asthma relationship.

Study of transforming growth factor alpha for the maintenance of human embryonic stem cells

Human embryonic stem cells (hESCs) have great potential for regenerative medicine as they have self-regenerative and pluripotent properties. Feeder cells or their conditioned medium are required for the maintenance of hESC in the undifferentiated state. Feeder cells have been postulated to produce growth factors and extracellular molecules for maintaining hESC in culture. The present study has aimed at identifying these molecules. The gene expression of supportive feeder cells, namely human foreskin fibroblast (hFF-1) and non-supportive human lung fibroblast (WI-38) was analyzed by microarray and 445 genes were found to be differentially expressed. Gene ontology analysis showed that 20.9% and 15.5% of the products of these genes belonged to the extracellular region and regulation of transcription activity, respectively. After validation of selected differentially expressed genes in both human and mouse feeder cells, transforming growth factor α (TGFα) was chosen for functional study. The results demonstrated that knockdown or protein neutralization of TGFα in hFF-1 led to increased expression of early differentiation markers and lower attachment rates of hESC. More importantly, TGFα maintained pluripotent gene expression levels, attachment rates and pluripotency by the in vitro differentiation of H9 under non-supportive conditions. TGFα treatment activated the p44/42 MAPK pathway but not the PI3K/Akt pathway. In addition, TGFα treatment increased the expression of pluripotent markers, NANOG and SSEA-3 but had no effects on the proliferation of hESCs. This study of the functional role of TGFα provides insights for the development of clinical grade hESCs for therapeutic applications.

Enhanced 355-nm generation using a simple method to compensate for walk-off loss

We theoretically and experimentally investigated a novel walk-off-compensation method for efficient ultraviolet beam generation. Through theoretical investigation, we described in detail how the power of a generated UV beam can be enhanced by the method; thus, we obtained a brief expression for the output power which has a prediction error of about 30%. In addition, we found that the beam quality can also be enhanced using this method. Through experiments using an alpha barium borate crystal as a walk-off compensator, we found that the power of the generated ultraviolet beam increased 1.9 times.

Factors affecting the impact of olfactory loss on the quality of life and emotional coping ability

BACKGROUND

Olfactory impaired patients have decreased quality of life and may need to develop a coping ability for the olfactory loss. This study investigated how factors like olfactory function, disease duration, etiology, age, and gender affect patients` quality of life and emotional ability to cope.

METHODS

Four hundred and thirteen consecutive patients with the chief complaint of olfactory dysfunction were evaluated. The Questionnaire of Olfactory Disorders (QOD) included negative statements (QOD-NS) that indicated the impact on the quality of life, and positive statements (QOD-PS) reflecting the emotional coping ability. Relations between studied factors and QOD-NS or QOD-PS were analyzed.

RESULTS

Poorer olfaction and younger age correlated with increased QOD-NS scores, whereas longer disease duration and older age correlated with increased QOD-PS scores. Females had poorer coping than males. QOD-PS scores were inversely related to QOD-NS scores.

CONCLUSIONS

The impact of olfactory loss is more significantly felt by younger patients with poorer olfaction. Older patients or those with longer disease duration develop better emotional coping abilities so as to reduce the impact on quality of life. It may be helpful for the patients with olfactory loss to develop emotional coping as early as possible to decrease the olfactory impact.

Filaggrin polymorphism P478S, IgE level, and atopic phenotypes

BACKGROUND

Whether environmental exposures may modulate the effect of the skin barrier gene on atopic dermatitis (AD) remains to be elucidated.

OBJECTIVES

To determine whether filaggrin (FLG) variants can serve as a predictor for atopic disorders in Chinese individuals and if allergen exposures may modify the effect of FLG variants on AD by total IgE levels.

METHODS

In total, 116 children aged 2-5years with AD and 212 control subjects were analysed for the FLG variants using DNA sequencing. Multiple logistic regression models were performed to estimate the association among FLG polymorphisms and atopic phenotypes. Serum total IgE level, standing for the degree of allergen exposures, was later stratified to determine the effects of FLG polymorphisms on AD.

RESULTS

A significant difference in genotype frequency was found among AD cases and controls in FLG P478S polymorphism. FLG P478S GG genotype significantly increased the risk of AD [odds ratio (OR) 4·60, 95% confidence interval (CI) 1·88-11·24]. In addition, among subjects with AD, GG genotypes also significantly increased the risk of developing asthma (OR 4·68, 95% CI 1·37-16·03). Further, a similar result was obtained for allergic rhinitis (OR 3·23, 95% CI 1·01-10·30). Interestingly, the P478S GG genotype was significantly related to AD (OR 5·67, 95% CI 1·93-16·60) in children with IgE level ≥100 kU L(-1) . However, the association was not evident when IgE level was < 100 kU L(-1) .

CONCLUSIONS

Our results suggest that the FLG P478S polymorphism may confer susceptibility to the development of AD among Chinese individuals and may be modified by IgE levels.

Pituitary adenylate cyclase-activating polypeptide-immunoreactive cells in the ageing gerbil hippocampus

In the present study, we investigated age-related changes in pituitary adenylate cyclase-activating polypeptide (PACAP) immunoreactivity and its protein levels in the gerbil hippocampus at various ages using immunohistochemistry and western blot analysis. In the post-natal month 1 (PM 1) group, PACAP-immunoreactive cells were found in all hippocampal subregions. The number of PACAP-immunoreactive cells was decreased in the PM 3 group and was still more decreased in the PM 6 and 12 groups. Thereafter, in the PM 18 and 24 groups, PACAP-immunoreactive cells were significantly increased again. However, in the mossy fibre zone, PACAP immunostaining was very strong in the adult group, especially in the PM 6 group. In addition, PACAP protein level was highest at PM 6, showing a slight decrease at PM 24. These results indicate that PACAP-immunoreactive cells are lowest in the adult stage and highest in the aged stage. However, PACAP immunoreactivity in the mossy fibre zone and PACAP protein level in the hippocampus are highest in the adult stage.

Nationwide periodic health examinations promote early treatment of hypertension, diabetes and hyperlipidemia in adults: experience from Taiwan

OBJECTIVES

To investigate the effectiveness of nationwide periodic health examinations in promoting early treatment of hypertension, diabetes and hyperlipidemia in adults aged ≥40 years.

STUDY DESIGN

Seven-year, retrospective, cohort study.

METHODS

Based on a large and representative claims dataset in Taiwan, cohort analysis was undertaken among three disease-free cohorts for hypertension, diabetes and hyperlipidemia (n = 26,661, 29,872 and 30,712 subjects, respectively) in 2000. Each cohort was observed from January 2001 to December 2007. Logistic regression, Cox proportional hazards analysis and the extended Cox model with counting process were employed in data analysis. Covariates such as age, gender, level of premium, beneficiary category, comorbidities and geographic factors were adjusted at baseline.

RESULTS

For the hypertension, diabetes and hyperlipidemia cohorts, those who had ever used the preventive service between 1998 and 2000 had higher probabilities of being treated as new patients for these target diseases; the hazard ratios were 1.65, 1.32 and 1.57, respectively. Using the extended Cox model, associations for use of each service with treatment within a 1-year follow-up period between 2001 and 2007 were 1.68, 2.41 and 3.48.

CONCLUSIONS

In adults who were initially disease-free, those who used the preventive service had higher probabilities of early treatment of these target diseases. These findings indicate the effectiveness of nationwide periodic health examinations.

Microtubule associated protein 2 and choline acetyltransferase immunoreactivity in the lumbar spinal cord of young adult and aged dogs

German Shepherds are a good model for research about aging and neurological disorders such as lumbosacral spinal canal stenosis. We compared neurons, glia and cholinergic neurons in the ventral horn of the lumbar spinal cord (L(3)) between adult (1-2 years old) and aged (10-12 years old) groups. Any pathological findings were not found by hematoxylin and eosin staining and neurological examination, and the number of NeuN (a marker for neurons)-positive neurons were similar in both groups. Microtubule-associated protein 2 (MAP2) immunoreactive dendrites in the aged dog were decreased without any change in β-tubulin protein level. Glial fibrillary acidic protein (a marker for astrocytes) and ionized calcium-binding adapter molecule 1 (a marker for microglia) immunoreactivity were not significantly changed in both groups. The number of ChAT immunoreactive neurons was decreased; however, its protein level was not significantly changed in the aged group. These results suggest that numbers of ventral horn neurons are not changed, but cholinergic neurons may change in aged dogs compared to adult dogs.

Silver Nitrate Stain Masquerading as an Avulsion Fracture of the Finger

We report a case of silver nitrate stain on the finger that masqueraded as an avulsion fracture on radiograph. Radiopacity in the proximal phalanx was demonstrated on radiograph after topical silver nitrate was applied to achieve haemostasis to a bleeding laceration on that area. The radiopacity was initially diagnosed as an avulsion fracture. The correct diagnosis of radiopacity corresponding to silver nitrate application was confirmed by correlation of physical examination with radiographic finding. The lesion spontaneously resolved with conservative management. The importance of correlating the clinical site of silver nitrate application with radiographic finding for accurate diagnosis and avoidance of unnecessary surgical intervention is emphasized.

Glutathione S-transferase, incense burning and asthma in children

Incense burning is a popular practice in many family homes and temples. However, little is known about the effects of indoor incense burning and genetic polymorphisms on asthma. This study evaluated the effects of indoor incense burning and glutathione S-transferase (GST) genetic polymorphisms on asthma and wheeze. In 2007, 3,764 seventh-grade schoolchildren (mean±sd age 12.42±0.65 yrs) were evaluated using a standard questionnaire for information about respiratory symptoms and environmental exposures. Multiple logistic regressions were performed to assess the association between GST polymorphisms and incense burning frequency on asthma and wheeze, after adjusting for potential confounders. The frequency of incense burning at home was associated with increased risk of current asthma (p=0.05), medication use (p=0.03) and exercise wheeze (p=0.001). GST1 (GSTT1) null genotypes were associated with current asthma (OR 1.43, 95% CI 1.00-2.04) and medication use (OR 1.46, 95% CI 1.01-2.22). GSTT1 showed a significant interactive effect with incense burning on current asthma, current wheeze and nocturnal wheeze. The frequency of incense burning was associated with increased risk of current asthma, medication use, lifetime wheeze, nocturnal wheeze and exercise wheeze in an exposure-response manner among children with GSTT1 null genotype (p<0.05). Incense burning is a risk factor for asthma and wheezing, especially in GSTT1 genetically susceptible children.

Mode tailoring in a ridge-type periodically poled lithium niobate waveguide

We present a simple and powerful method for mode generation and transformation in a ridge-type periodically poled lithium niobate (PPLN) waveguide by the use of second-order nonlinear effect and local-temperature-control technique. We show that a Hermite-Gaussian (HG) mode wave (among HG(00) to HG(22)) can be selectively generated via the quasi-phase-matching (QPM) nonlinear process in a PPLN waveguide by tuning the wavelength of fundamental wave or the temperature of the waveguide. As well, it is demonstrated that HG mode can be transformed into Laguerre-Gaussian (LG) one via combination of HG modes which are simultaneously generated in a single PPLN waveguide with local-temperature-control technique.

A linearly-polarized Nd:YVO4/KTP microchip green laser

We described the principle and the fabrication of a Nd:YVO(4)/KTP microchip for the linearly-polarized green laser and verified its availability by manufacturing and characterizing the green laser using the microchip. Under the driving condition having the modulation frequency of 60 Hz and the duty ratio of 25%, the laser showed the stable linear polarization, the maximum average power of 37 mW, yielding the high electrical-to-optical efficiency of 10.9%.

Characteristics of a multi-mode interference device based on Ti:LiNbO3 channel waveguide

We have analyzed the multi-mode interference effect depending on the wavelength and the polarization states of input beam in a multi-mode Ti:LiNbO(3) waveguide at about 1300 nm region. The transmitted optical signal of a Ti:LiNbO(3) waveguide shows the periodic oscillation as a function of input wavelength. The measured average periodicity of the oscillation in TM and TE polarization beams were about 18 nm and 48 nm, respectively. Actually, the periodicity is determined by the refractive index difference between the two modes (fundamental and first modes). Therefore, we have explained the experimental results with the theoretical calculations which are derived from a quasi-analytical technique based on the effective-refractive- index method and the equation of coupling length determined by the mode phase factor in the multi-mode waveguide.

Wavelength filtering characteristics of Solc filter based on Ti:PPLN channel waveguide

We have analyzed the Solc filtering characteristics in a periodically poled Ti:LiNbO3 (Ti:PPLN) multimode waveguide. The single- and dual-wavelength filtering were achieved under the optimized guiding condition for the TEM(00)-like mode and two mode (TEM(00)- and TEM(01)-like mode), respectively. The full width at half-maximum of the filter was about 0.21 nm at both guiding conditions. We found that the origin of two peaks of the dual-wavelength Solc filter in the two-mode guiding condition is the different effective refractive index between the TEM(00)- and TEM(01)-like modes. The wavelength difference of two peaks is about 0.8 nm at room temperature.

Low loss high mesa optical waveguides based on InGaAsP/InP heterostructures

Low loss high mesa optical waveguides were fabricated on InGaAsP/InP heterostructures by utilizing inductively-coupled-plasma reactive ion etching (ICP-RIE) and electron beam lithography technique. The fabrication process was optimized by measuring sidewall roughness of deep-etched waveguides. Atomic force microscope loaded with carbon nanotude was used to obtain three-dimensional image of the etched sidewall of waveguides. The obtained statistical information such as rms roughness and correlation length was used to theoretically calculate scattering loss of waveguides. Several waveguides with different number of sharp bends and the length were fabricated and their propagation losses were measured by modified Fabry-Perot method. The measured propagation losses were compared with theoretically calculated losses.

Effect of cordycepin on Hantaan virus 76-118 infection of primary human embryonic pulmonary fibroblasts--characterization of apoptotic effects

The cDNA microarray technique was used to study gene epression in human embryonic pulmonary fibroblasts (HEPF) infected with Hantaan virus (HTNV) under the influence of cordycepin (Cor), an inhibitor of post-transcriptional pre-mRNA polyadenylation. Four apoptotic genes, the insulin-like growth factor binding protein 1, NFkB inhibitor alpha, caspase-3 and NFkB1 were up-regulated in both infected and uninfected Cor-treated cells and two cell cycle-associated genes, CDC-like kinase and beta-induced transforming growth factor were up-regulated in Cor-untreated cells but down-regulated in Cor-treated cells. Cell morphology examination, quantitative RT-PCR, and immunofluorescence (IF) test suggested that following the Cor treatment the HTNV infection took place, but late viral gene expression was slightly reduced. Three parameters, namely caspase-3 activity, annexin V binding, and cell cycle were used to detect apoptosis. The results suggested that the induction of apoptosis in HEPF by HTNV started at 6 hrs post infection (p.i.). Following the Cor treatment, however, the caspase-3 activity began to increase at 24 hrs p.i. Thus it is suggested that inhibition of de novo late viral protein synthesis by Cor changes the apoptosis pathway and cell cycle by delaying caspase-3 gene expression and by up/down-regulating of expression of other apoptotic and cell cycle-associated genes. This implicates that HTNV can induce apoptosis in HEPF even without de novo viral protein synthesis and with a reduced and slowed viral maturation.

Demonstration of different modes of cell death upon herpes simplex virus 1 infection in different types of oral cells

The effects of Herpes simplex virus 1 (HSV-1) infection on five different types of oral cancerous cells (neck metastasis of gingival carcinoma (GNM) cells and tongue squamous cells of carcinoma (TSCCa) and non-cancerous cells (buccal mucosal fibroblasts (BF), gingival fibroblasts (GF), oral submucosal fibrosis cells (OSF)) and one type of non-oral cancerous cells (KB cells) were investigated. In HSV-1-infected cells the cell viability, CPE, viral antigens accumulation, caspase-3 activity, annexin V binding and DNA fragmentation were estimated. Three different forms or pathways of cell death were considered: apoptosis (the presence or rise of caspase-3 activity, DNA fragmentation and annexin V binding), slow cell death (the presence or rise of DNA fragmentation, the absence or decline of caspase-3 activity and annexin V binding), and necrosis (the absence of decline of caspase-3 activity, DNA fragmentation and annexin V binding). The viability of all cell types, except for KB cells, was reduced by the infection. CPE and viral antigens data demonstrated that all six types of cells could be infected with HSV-1. Upon HSV-1 infection there occurred (i) a classical apoptosis in GF cells, (ii) apoptosis in the early phase of infection and necrosis in the late phase of infection in GNM and TSCCa cells, (iii) slow cell death followed by necrosis in BF and OSF cells (however, these cells showed a different type of CPE), (iv) a classical slow cell death in KB cells. It is hypothesized that HSV-1 infection has a potential to induce several distinct pathways leading to cell death or several forms of cell death. Moreover, more than one pathway may be involved in the death of particular cell type. As HSV-1 was demonstrated to infect different oral and non-oral cells and cause different pathways or forms of cell death, the safety of using HSV-1 as a vector for gene therapy should be re-considered.

Embryotrophic factor-3 from human oviductal cells enhances proliferation, suppresses apoptosis and stimulates the expression of the β1 subunit of sodium–potassium ATPase in mouse embryos

BACKGROUND

Embrytrophic factor-3 (ETF-3) from human oviductal cells enhanced the development of mouse preimplantation embryos. This report studied the embryotrophic mechanisms of the molecule.

METHODS AND RESULTS

Mouse embryos were incubated with ETF-3 for 24 h at different stages of development. ETF-3 treatment between 96 and 120 h post-HCG increased the cell count of blastocysts, whilst treatment between 72 and 96 h post-HCG enhanced the expansion and hatching of the blastocysts. ETF-3 increased the cell number of the embryos by suppressing apoptosis and increasing proliferation as determined by TUNEL and bromodeoxyuridine uptake assays, respectively. Real-time quantitative PCR showed that the in vivo developed and ETF-3-treated blastocysts had a significantly higher mRNA copy number of Na/K-ATPase-beta1, but not of hepsin, than that of blastocysts cultured in medium alone. The former gene was associated with cavitation of blastocysts while the latter was related to hatching of blastocyst. The beneficial effect of ETF-3 on blastocyst hatching was also seen when ETF-3-supplemented commercially available sequential culture medium for human embryo culture was used to culture mouse embryos.

CONCLUSIONS

ETF-3 improves embryo development by enhancing proliferation, suppressing apoptosis and stimulating expression of genes related to blastocyst cavitation. Supplementating human embryo culture medium with ETF-3 may improve the success rate in clinical assisted reproduction.

Peritonsillar infections: local experience

INTRODUCTION

The disease pattern and management of peritonsillar infections in Singapore General Hospital are studied. Other objectives are to determine if a seasonal variation exists and to examine the role of routine bacterial cultures and interval tonsillectomy.

METHODS

This is a retrospective review of the management and outcome of patients with peritonsillar infections who were admitted acutely to Singapore General Hospital over a three-year period.

RESULTS

Of 185 patients studied, 151 (81.6 percent) had peritonsillar abscess or quinsy and 34 (18.4 percent) had peritonsillar cellulitis. There were 139 males and 46 females, with a racial predisposition among Malays (p value is less than 0.0005). There may be a seasonal variation with a bi-annual trend, though no correlation with upper respiration tract infections was noted. Treatment consisted mainly of incision and drainage (66 percent) or needle aspiration (34 percent). No significant difference in the length of stay was noted in patients receiving penicillin alone, penicillin with metronidazole, or broad-spectrum antibiotics (p value is equal to 0.062). Fourteen (7.6 percent) patients had recurrences, all of which occurred after the first month. Two patients (1 percent) had bilateral quinsy.

CONCLUSION

Peritonsillar infections remain a common admitting diagnosis to the Otolaryngology department. A single episode of infection should no longer be an indication for tonsillectomy as the incidence of recurrence is low.

Climate, traffic-related air pollutants and allergic rhinitis prevalence in middle-school children in Taiwan

The prevalence of allergic rhinitis, a common respiratory disorder, may be rapidly increasing. Epidemiological studies, however, indicate little about its association with climatic factors and air pollution. The relationship between traffic-related air pollutants and allergic rhinitis in middle-school students was therefore investigated. In a nationwide survey of middle-school students in Taiwan conducted in 1995/1996, the lifetime prevalence of physician-diagnosed allergic rhinitis and typical symptoms of allergic rhinitis were compared with air-monitoring station data on temperature, relative humidity, sulphur dioxide (SO2), nitrogen oxides (NOx), ozone (O3), carbon monoxide (CO) and particulate matter with a 50% cut-off aerodynamic diameter of 10 microm (PM10). A total of 331,686 nonsmoking children attended schools located within 2 km of 55 stations. Mean (range) annual exposures were: CO 853 (381-1,610) parts per billion (ppb), NOx 35.1 (10.2-72.4) ppb, SO2 7.57 (0.88-21.2) ppb, PM10 69.2 (40.1-116.2) microg x m(-3), O3 21.3 (12.4-34.1) ppb, temperature 22.9 (19.6-25.1) degrees C, and relative humidity 76.2 (64.8-86.2)%. The prevalence of physician-diagnosed allergic rhinitis was 28.6 and 19.5% in males and females, respectively, with prevalence of questionnaire-determined allergic rhinitis 42.4 and 34.0%. After adjustment for age, parental education and history of atopic eczema, physician-diagnosed allergic rhinitis was found to be associated with higher nonsummer (September-May) warmth and traffic-related air pollutants, including CO, NOx and O3. Questionnaire-determined allergic rhinitis correlated only with traffic-related air pollutants. Nonsummer warmth and traffic-related air pollution, probably mediated through exposure to common allergens such as dust mites, are possible risk factors for allergic rhinitis in middle-school-aged children.

Embryotrophic factor-3 from human oviductal cells affects the messenger RNA expression of mouse blastocyst

Our previous results showed that embryotrophic factor-3 (ETF-3) from human oviductal cells increased the size and hatching rate of mouse blastocysts in vitro. The present study investigated the production of ETF-3 by an immortalized human oviductal cell line (OE-E6/E7) and the effects of ETF-3 on the mRNA expression of mouse embryos. The ETF-3 was purified from primary oviductal cell conditioned media using sequential liquid chromatographic systems, and antiserum against ETF-3 was raised. The ETF-3-supplemented Chatot-Ziomek-Bavister medium was used to culture Day 1 MF1 x BALB/c mouse embryos for 4 days. The ETF-3 treatment significantly enhanced the mouse embryo blastulation and hatching rate. The antiserum, at concentrations of 0.03-3%, abolished the embryotrophic effect of ETF-3. Positive ETF-3 immunoreactivity was detected in the primary oviductal cells, OE-E6/E7, and blastocysts derived from ETF-3 treatment. Vero cells (African Green Monkey kidney cell line), fibroblasts, and embryos cultured in control medium did not possess ETF-3 immunoreactivity. The mRNA expression patterns of the treated embryos were studied at the blastocyst stage by mRNA differential display reverse transcription-polymerase chain reaction (DDRT-PCR). The DDRT-PCR showed that some of the mRNAs were differentially expressed after ETF-3 treatment. Twelve of the differentially expressed mRNAs that had high homology with cDNA sequences in the GenBank were selected for further characterization. The differential expression of seven of these mRNAs (ezrin, heat shock 70-kDa protein, cytochrome c oxidase subunit VIIa-L precursor, proteinase-activated receptor 2, eukaryotic translation initiation factor 2beta, cullin 1, and proliferating cell nuclear antigen) was confirmed by semiquantitative RT-PCR. In conclusion, immortalized oviductal cells produce ETF-3, which influences mRNA expression of mouse blastocyst.

The proteins of synaptic vesicle membranes are affected during ageing of rat brain

Low molecular weight GTP-binding proteins are molecular switches that are believed to play pivotal roles in cell growth, differentiation, cytoskeletal organization, and vesicular trafficking. Rab proteins are key players in the regulation of vesicular transport, while Rho family members control actin-dependent cell functions, i.e. the regulation of cytoskeletal organization in response to extracelluar growth factors and in dendritic neuron development. In this study, we have examined the regulation of small GTP-binding proteins that are implicated in neurosecretion and differentiation of neuron during ageing processes. Comparison of small GTP-binding proteins from the synaptosome and crude synaptic vesicles (LP2 membranes) of 2 months and 20 months old rat brain respectively showed no difference in the level of Rab family proteins (Rab3A and Rab5A). However, Rho family proteins such as RhoA and Cdc42 were elevated in LP2 membranes of the aged brain. The dissociation of Rab3A by Ca2+/calmodulin (CaM) from SV membranes was not changed during aging. Ca2+/CaM stimulated phosphorylation of the 22 and 55-kDa proteins in SV membranes from the aged rat brain, and inhibited phosporylation of 30-kDa proteins. GTPgammaS inhibited phosphorylation of the 100-kDa proteins and stimulated phosphorylation of the 70 kDa in LP2 membranes from both the young and aged rat brains, whereas GDPbetaS caused just the opposite reaction. These results suggest that protein phosphorylation and regulation of Rho family GTPases in rat brain appears to be altered during ageing processes.

Formation of protoberberine-type alkaloids by the tubers of somatic embryo-derived plants of Corydalis yanhusuo

The effects of 0.5 - 5 mg/l abscisic acid [ABA], 0.5 - 10 mg/l (2RS,3RS)-1-(4-chlorophenyl)-4,4-dimethyl-2-(1,2,4-triazol-1-yl)pentan-3-ol [paclobutrazol] and 0.5 - 2 mg/l alpha-cyclopropyl-alpha-(4-methoxyphenyl)-5-pyrimidinemethanol [ancymidol], 0.5 - 5 mg/l gibberellic acid [GA(3)] and 15 - 100 mg/l polyethylene glycol [PEG] 4000 supplemented in half-strength Murashige and Skoog's (MS) medium on the production of the two major protoberberine-type alkaloids (D,L-tetrahydropalmatine and D-corydaline) by the tubers of somatic embryo-derived plants of Corydalis yanhusuo were examined. Somatic embryo derived plants were also maintained for 6 months on half-strength MS medium containing 0.1 mg/l GA(3) or 0.5 mg/l paclobutrazol. The alkaloid contents were determined by high performance liquid chromatography (HPLC). The analysis revealed that the contents of D,L-tetrahydropalmatine and D-corydaline in the tubers of somatic embryo-derived plants were higher than the marketed crude drug and varied with growth regulator/PEG-4000 treatment and the age of the plant.

Image display for collision avoidance of radiation therapy: treatment planning

Patient treatment in a medical linear accelerator is characterized by many angular and translational movements of the gantry and couch. The direction and orientation of each treatment beam is specified by a set of gantry, turntable, and collimator angles. It is possible that some selected treatment field configurations will result in gantry/couch or gantry/patient collisions that remain undetected during the treatment planning process. In this work, a digital camera has been used to record all the workable gantry/ patient set-up images, and a Windows programming language is used to edit and display these images on a personal computer for the treatment planner to screen the treatment plans. These graphical displays enable the planner to be aware of any potential collision hazards by an actual visualization of each selected gantry/turntable or gantry/patient angle configuration.

Construction of single-chain interleukin-12 DNA plasmid to treat airway hyperresponsiveness in an animal model of asthma

Allergic asthma is strongly associated with the airway inflammation caused by the dysregulated production of cytokines secreted by the allergen-specific type-2 T helper (Th2) cells. Interleukin (IL)-12 is a heterodimeric cytokine, which strongly promotes the differentiation of naive CD4(+) T cells to the type-1 T helper (Th1) phenotype and suppresses the expression of Th2 cytokines. Therefore, immunotherapy with IL-12 has been suggested as a possible therapy for asthma. In previous studies, we developed a murine model of airway inflammation based on the purified, house dust-mite allergen Der p 1 (Dermatophagodies pteronyssinus) as a clinically relevant allergen. We hypothesized that the expression of IL-12 in the airway may represent an effective therapy for allergic airway diseases. In this study, we investigate whether the local transfer of the IL-12 gene to respiratory tissues modifies allergic inflammation and airway hyper-responsiveness (AHR) in our disease model. To enhance the in vivo delivery of the IL-12 gene, we expressed the murine single-chain IL-12 protein from a nonviral vector to which the two IL-12 subunits (p35 and p40) were linked by a 14- to 18-amino-acid linker. One of these single-chain IL-12s, containing an 18 amino-acid polypeptide linker, was stably expressed and had a high level of biological activity comparable to that of native IL-12 in vitro. In mice with Der p 1-induced asthma, the local administration of this IL-12 fusion gene into the lungs significantly prevented the development of AHR, abrogated airway eosinophilia, and inhibited type-2 cytokine production. These findings indicate that the local transfer of the single-chain IL-12 gene is effective in modulating pulmonary allergic responses and may be a convenient method for future applications of DNA vaccination.