Race and Antibiotic Use for Children Hospitalized With Acute Respiratory Infections

We sought to evaluate whether children hospitalized with acute respiratory infections experienced differences in antibiotic use by race and ethnicity. We found that likelihood of broad-spectrum antibiotic receipt differed across racial and ethnic groups. Future work should confirm this finding, evaluate causes, and ensure equitable antibiotic use.

Multiomics reveals glutathione metabolism as a driver of bimodality during stem cell aging

With age, skeletal muscle stem cells (MuSCs) activate out of quiescence more slowly and with increased death, leading to defective muscle repair. To explore the molecular underpinnings of these defects, we combined multiomics, single-cell measurements, and functional testing of MuSCs from young and old mice. The multiomics approach allowed us to assess which changes are causal, which are compensatory, and which are simply correlative. We identified glutathione (GSH) metabolism as perturbed in old MuSCs, with both causal and compensatory components. Contrary to young MuSCs, old MuSCs exhibit a population dichotomy composed of GSHhigh cells (comparable with young MuSCs) and GSHlow cells with impaired functionality. Mechanistically, we show that antagonism between NRF2 and NF-κB maintains this bimodality. Experimental manipulation of GSH levels altered the functional dichotomy of aged MuSCs. These findings identify a novel mechanism of stem cell aging and highlight glutathione metabolism as an accessible target for reversing MuSC aging.

Plasmodium knowlesi circumsporozoite protein: genetic characterisation and predicted antigenicity of the central repeat region

Circumsporozoite protein (CSP) central repeat region is one of the main target regions of the RTS,S/AS01 vaccine for falciparum infection as it consists of immunodominant B cell epitopes. However, there is a lack of study for P. knowlesi CSP central repeat region. This study aims to characterise the CSP repeat motifs of P. knowlesi isolates in Peninsular Malaysia. CSP repeat motifs of 64 P. knowlesi isolates were identified using Rapid Automatic Detection and Alignment of Repeats (RADAR). Antigenicity of the repeat motifs and linear B cell epitopes were predicted using VaxiJen 2.0, BepiPred-2.0 and BCPred, respectively. A total of 35 dominant repeat motifs were identified. The repeat motif "AGQPQAQGDGANAGQPQAQGDGAN" has the highest repeat frequency (n=15) and antigenicity index of 1.7986. All the repeat regions were predicted as B cell epitopes. In silico approaches revealed that all repeat motifs were antigenic and consisted of B cell epitopes which could be designed as knowlesi malaria vaccine.

Fasting induces a highly resilient deep quiescent state in muscle stem cells via ketone body signaling

Short-term fasting is beneficial for the regeneration of multiple tissue types. However, the effects of fasting on muscle regeneration are largely unknown. Here, we report that fasting slows muscle repair both immediately after the conclusion of fasting as well as after multiple days of refeeding. We show that ketosis, either endogenously produced during fasting or a ketogenic diet or exogenously administered, promotes a deep quiescent state in muscle stem cells (MuSCs). Although deep quiescent MuSCs are less poised to activate, slowing muscle regeneration, they have markedly improved survival when facing sources of cellular stress. Furthermore, we show that ketone bodies, specifically β-hydroxybutyrate, directly promote MuSC deep quiescence via a nonmetabolic mechanism. We show that β-hydroxybutyrate functions as an HDAC inhibitor within MuSCs, leading to acetylation and activation of an HDAC1 target protein p53. Finally, we demonstrate that p53 activation contributes to the deep quiescence and enhanced resilience observed during fasting.

The curious case of missing heartbeats

Paroxysmal atrioventricular block (AVB) is a poorly defined and easily missed bradyarrhythmia, which can potentially lead to sudden cardiac death. It is under-recognised due to its abrupt onset and unpredictability. We describe a case that had paroxysmal AVB post-coronary angioplasty and highlight the mechanism as well as the management of this rare condition.

Textbook outcome following oesophagectomy for cancer: international cohort study

Background

Textbook outcome has been proposed as a tool for the assessment of oncological surgical care. However, an international assessment in patients undergoing oesophagectomy for oesophageal cancer has not been reported. This study aimed to assess textbook outcome in an international setting.

Methods

Patients undergoing curative resection for oesophageal cancer were identified from the international Oesophagogastric Anastomosis Audit (OGAA) from April 2018 to December 2018. Textbook outcome was defined as the percentage of patients who underwent a complete tumour resection with at least 15 lymph nodes in the resected specimen and an uneventful postoperative course, without hospital readmission. A multivariable binary logistic regression model was used to identify factors independently associated with textbook outcome, and results are presented as odds ratio (OR) and 95 per cent confidence intervals (95 per cent c.i.).

Results

Of 2159 patients with oesophageal cancer, 39.7 per cent achieved a textbook outcome. The outcome parameter ‘no major postoperative complication’ had the greatest negative impact on a textbook outcome for patients with oesophageal cancer, compared to other textbook outcome parameters. Multivariable analysis identified male gender and increasing Charlson comorbidity index with a significantly lower likelihood of textbook outcome. Presence of 24-hour on-call rota for oesophageal surgeons (OR 2.05, 95 per cent c.i. 1.30 to 3.22; P = 0.002) and radiology (OR 1.54, 95 per cent c.i. 1.05 to 2.24; P = 0.027), total minimally invasive oesophagectomies (OR 1.63, 95 per cent c.i. 1.27 to 2.08; P < 0.001), and chest anastomosis above azygous (OR 2.17, 95 per cent c.i. 1.58 to 2.98; P < 0.001) were independently associated with a significantly increased likelihood of textbook outcome.

Conclusion

Textbook outcome is achieved in less than 40 per cent of patients having oesophagectomy for cancer. Improvements in centralization, hospital resources, access to minimal access surgery, and adoption of newer techniques for improving lymph node yield could improve textbook outcome.

Textbook outcome following oesophagectomy for cancer: international cohort study

BACKGROUND

Textbook outcome has been proposed as a tool for the assessment of oncological surgical care. However, an international assessment in patients undergoing oesophagectomy for oesophageal cancer has not been reported. This study aimed to assess textbook outcome in an international setting.

METHODS

Patients undergoing curative resection for oesophageal cancer were identified from the international Oesophagogastric Anastomosis Audit (OGAA) from April 2018 to December 2018. Textbook outcome was defined as the percentage of patients who underwent a complete tumour resection with at least 15 lymph nodes in the resected specimen and an uneventful postoperative course, without hospital readmission. A multivariable binary logistic regression model was used to identify factors independently associated with textbook outcome, and results are presented as odds ratio (OR) and 95 per cent confidence intervals (95 per cent c.i.).

RESULTS

Of 2159 patients with oesophageal cancer, 39.7 per cent achieved a textbook outcome. The outcome parameter 'no major postoperative complication' had the greatest negative impact on a textbook outcome for patients with oesophageal cancer, compared to other textbook outcome parameters. Multivariable analysis identified male gender and increasing Charlson comorbidity index with a significantly lower likelihood of textbook outcome. Presence of 24-hour on-call rota for oesophageal surgeons (OR 2.05, 95 per cent c.i. 1.30 to 3.22; P = 0.002) and radiology (OR 1.54, 95 per cent c.i. 1.05 to 2.24; P = 0.027), total minimally invasive oesophagectomies (OR 1.63, 95 per cent c.i. 1.27 to 2.08; P < 0.001), and chest anastomosis above azygous (OR 2.17, 95 per cent c.i. 1.58 to 2.98; P < 0.001) were independently associated with a significantly increased likelihood of textbook outcome.

CONCLUSION

Textbook outcome is achieved in less than 40 per cent of patients having oesophagectomy for cancer. Improvements in centralization, hospital resources, access to minimal access surgery, and adoption of newer techniques for improving lymph node yield could improve textbook outcome.

The impact of the COVID-19 pandemic on transcatheter aortic valve implantation (TAVI) service: a United Kingdom tertiary centre experience

Background/Introduction

Untreated, symptomatic, severe aortic stenosis carries significant mortality and morbidity. Timely intervention is pivotal to ensure patient safety. The COVID-19 pandemic created unprecedented challenges to the UK's National Health Service (NHS), resulting in the deferral of all elective work, including TAVI services from March 2020.

Purpose

To evaluate clinical outcomes and time delays in patients undergoing TAVI during the pandemic period compared to an age and risk factor-matched cohort of patients prior to COVID-19. We hypothesized that there were significant time delays, more emergency procedures and related adverse outcomes in patients who underwent TAVI during the pandemic period.

Methods

We analysed prospectively collected data (patient characteristics, procedural details, complications and in-hospital outcomes) of 210 consecutive patients who underwent TAVI between March 2019 and February 2021 in a tertiary centre in the UK (The centre serves for a population of 2.5 million and provided in-patient treatment for 5590 COVID-positive patients over a 12 month period). We compared time-lags from an initial referral to outpatient review, CT aortograms, valve implantation and 30-day mortality between patients who underwent TAVI between March 2019 and Feburary 2020 (N=134) and those who underwent TAVI between March 2020 and February 2021 (COVID Group=76).

Results

The mean age of the cohort was 81.4±6.6 years and majority were females (51%) and were in moderate risk category (EuroSCORE II=4.55±5.5). Of the total cohort, 4 (5.3%) patients acquired COVID-19 pneumonia during the hospital stay. The age, cardiovascular comorbidities and risk scores were comparable between the control group and the COVID cohort. (Table 1). There were no significant differences in procedural complications in the control group compared to the COVID-19 group (Table 1). The median waiting time from referral to TAVI clinic was significantly shorter in the COVID-19 group (33 (8–66) vs. 51 (17–89) days (P=0.04)) and there was no significant difference in time delays for CT aortogram, MDT or TAVI procedure between the two groups. The median length of stay (2 (2–4) vs 2.5 (2–9) days) and 30 day mortality (1.4% vs 5.3%) was comparable between the two groups (Table 1).

Conclusion

Contrary to our hypothesis, our analysis demonstrated that there were no significant time delays, excess complications or mortality in TAVI procedures during the COVID-19 pandemic period despite the excess burden imposed on our local health services. More importantly, very few TAVI patients acquired COVID-19 infection during in-hospital stay. This is likely due to prompt identification of innovative ways of re-configuring an existing local patient pathway, by the TAVI team, to deliver safe and uninterrupted TAVI services during this unprecedented pandemic setting.

Funding Acknowledgement

Type of funding sources: None. Figure 1. Referral times

Clinical outcomes up-to 10 years of asymptomatic incidental aortic dissections and large aortic aneurysms detected on computer tomography aortography (CTA) prior to transcatheter aortic valve implantation (TAVI)

Background/Introduction

Computer tomography aortography (CTA) is performed routinely to aid planning of transcatheter aortic valve implantation (TAVI). Incidental findings are common, and may influence the decision to proceed with TAVI. The safety and long term outcomes of performing TAVI in patients with previously undiagnosed incidental CT findings of aortic dissections and large aortic aneurysms is currently unknown.

Purpose

To establish the frequency of incidental aortic dissections and large aortic aneurysms prior to TAVI, and subsequent clinical outcomes of patients. We hypothesize that transfemoral access is safe in patients with incidental finding of aortic dissection and large aortic aneurysms.

Methods

This was a retrospective study of 628 sequential TAVI patients in a large, UK tertiary centre between January 2010 and September 2020. Patients were evaluated in 3 groups as per pre-TAVI CTA: incidental aortic dissections, aortic aneurysm &gt;4cm and all others (control group). Endpoints were procedural success, peri-procedural major bleeding and/or vascular complications and/or CVA, length of hospital stay, 30-day and 1-year mortality.

Results

2.9% of patients (n=18) had incidental aortic dissection, of which 66.7% (n=12) were male, with a mean age of 86.7±4.4. 3.8% of patients (n=24) had aortic aneurysms &gt;4 cm. 83.3% (n=20) of them were male and the mean age was 82.8±5.4. Transfemoral approach was favoured in 77.8% of patients in the dissection group and 83.3% of patients in the aneurysm group versus 93.3% in the control group. Procedural characteristics are summarised in Table 1. Vascular access complications, stroke, bleeding and length of hospital stay were comparable between all 3 groups (Table 1). Patients with dissection and large aneurysm had similar success rate of valve implantation compared to the control group (88.9% and 87.5% vs 97.1%, p=0.452). 30-day mortality in the dissection group was higher than the other 2 groups (21.1% vs 0% and 5.6%, p=0.004). Log-rank analysis revealed a higher incidence of MACE in the dissection group over 24 months compared to the other two groups (Figure 1).

Conclusion

A transfemoral approach appears to be a safe choice in patients with incidental findings of aortic dissection or aortic aneurysms &gt;4cm, given no significant difference in terms of valve implant success, vascular injury, major bleeding or unplanned surgical repair. However, patients with stable previous aortic dissections have a significantly higher 30-day mortality and overall lower survival rate over 24 months. This important observation needs to be further investigated in a larger-scale, long-term follow up study, and may in future influence TAVI treatment planning.

Funding Acknowledgement

Type of funding sources: None. Figure 1. Survival curve

Complications of Sub-microscopic Plasmodium vivax Malaria among Orang Asli in Pos Lenjang, Kuala Lipis

In recent years, increasing cases of Plasmodium vivax complications had been reported all over the world. This former benign Plasmodium species is now recognized to be one of the human malaria parasites that can produce severe disease. In this article, we report two cases of sub-microscopic P. vivax malaria confirmed by PCR. Both patients were asymptomatic before treatment. They showed unusual presentations few days after initiation of antimalarial treatment. Both patients had subsequently completed antimalarial treatment and recovered completely.

Wilms tumour with poor response to pre-operative chemotherapy: A report of 2 cases

INTRODUCTION

Majority of Wilms tumour (WT) responds well to pre-operative chemotherapy. In Malaysia, incidence of WT is rare with only two cases reported per one million populations yearly. This case report is to highlight on the awareness of WT in an Asian population and highlight two cases and challenges faced after pre-operative chemotherapy.

CASE REPORT

In this case series, we report on two cases of WT which had poor response to pre-operative chemotherapy. Both cases underwent surgery after pre-operative chemotherapy and recovery was uneventful during a two-year follow-up.

DISCUSSION

Both patients had chemotherapy prior planned surgery, but had unfortunate poor tumour response. The tumour progressed in size which required a radical nephrectomy. The histology report for the first case had more than 60% blastemal cells remaining despite giving pre-operative chemotherapy with no focal anaplasia. This showed poor response to chemotherapy evidenced by the high number of blastemal cells. The second case was a stromal type WT which is known for poor response and may lead to enhancement of growth and maturation induced by chemotherapy. These were the possible reason of poor response of WT in these two cases.

Positive-Parity Linear-Chain Molecular Band in ^{16}C

An inelastic excitation and cluster-decay experiment ^{2}H(^{16}C,^{4}He+^{12}Be or ^{6}He+^{10}Be)^{2}H was carried out to investigate the linear-chain clustering structure in neutron-rich ^{16}C. For the first time, decay paths from the ^{16}C resonances to various states of the final nuclei were determined, thanks to the well-resolved Q-value spectra obtained from the threefold coincident measurement. The close-threshold resonance at 16.5 MeV is assigned as the J^{π}=0^{+} band head of the predicted positive-parity linear-chain molecular band with (3/2_{π}^{-})^{2}(1/2_{σ}^{-})^{2} configuration, according to the associated angular correlation and decay analysis. Other members of this band were found at 17.3, 19.4, and 21.6 MeV based on their selective decay properties, being consistent with the theoretical predictions. Another intriguing high-lying state was observed at 27.2 MeV which decays almost exclusively to ^{6}He+^{10}Be(∼6  MeV) final channel, corresponding well to another predicted linear-chain structure with the pure σ-bond configuration.

Intrauterine contraceptive device embedded in bladder wall with calculus formation removed successfully with open surgery

An Intrauterine contraceptive devices (IUCD) is commonly inserted by the primary health care physician. It can migrate into pelvic or abdominal organs. When a pregnancy occurs following an insertion of an IUCD, there should be a high suspicion of uterine perforation or possible migration. A radiograph can be done in the primary health care clinic to search for a missing IUCD. Early referral to the urology service is warranted when a patient presents with recurrent urinary tract infections. Removal of an intravesical IUCD can be managed with cystoscopy, laparoscopy or open surgery. Herein, we report a case of IUCD migration into the bladder. This case will highlight the importance of proper technique, careful insertion and the role of ultrasound.

Caecal Volvulus after a dental procedure - not just constipation!

Caecal volvulus has been reported to be associated with various abdominal and pelvic pathologies. Its signs and symptoms are usually non-specific and maybe overlooked in favour of benign causes, such as constipation. A high degree of suspicion is required for prompt diagnosis. Herein, we report on an unusual case of caecal volvulus after a dental procedure that was managed initially as constipation.

An ANGPTL4-ceramide-protein kinase Cζ axis mediates chronic glucocorticoid exposure-induced hepatic steatosis and hypertriglyceridemia in mice

Chronic or excess glucocorticoid exposure causes lipid disorders such as hypertriglyceridemia and hepatic steatosis. Angptl4 (angiopoietin-like 4), a primary target gene of the glucocorticoid receptor in hepatocytes and adipocytes, is required for hypertriglyceridemia and hepatic steatosis induced by the synthetic glucocorticoid dexamethasone. Angptl4 has also been shown to be required for dexamethasone-induced hepatic ceramide production. Here, we further examined the role of ceramide-mediated signaling in hepatic dyslipidemia caused by chronic glucocorticoid exposure. Using a stable isotope-labeling technique, we found that dexamethasone treatment induced the rate of hepatic de novo lipogenesis and triglyceride synthesis. These dexamethasone responses were compromised in Angptl4-null mice (Angptl4^-/-). Treating mice with myriocin, an inhibitor of the rate-controlling enzyme of de novo ceramide synthesis, serine palmitoyltransferase long-chain base subunit 1 (SPTLC1)/SPTLC2, decreased dexamethasone-induced plasma and liver triglyceride levels in WT but not Angptl4^-/- mice. We noted similar results in mice infected with adeno-associated virus-expressing small hairpin RNAs targeting Sptlc2. Protein phosphatase 2 phosphatase activator (PP2A) and protein kinase Cζ (PKCζ) are two known downstream effectors of ceramides. We found here that mice treated with an inhibitor of PKCζ, 2-acetyl-1,3-cyclopentanedione (ACPD), had lower levels of dexamethasone-induced triglyceride accumulation in plasma and liver. However, small hairpin RNA-mediated targeting of the catalytic PP2A subunit (Ppp2ca) had no effect on dexamethasone responses on plasma and liver triglyceride levels. Overall, our results indicate that chronic dexamethasone treatment induces an ANGPTL4-ceramide-PKCζ axis that activates hepatic de novo lipogenesis and triglyceride synthesis, resulting in lipid disorders.

External validation of a modified trauma and injury severity score model in major trauma injury

BACKGROUND

The establishment of an accurate prognostic model in major trauma patients is important mainly because this group of patients will benefit the most. Clinical prediction models must be validated internally and externally on a regular basis to ensure the prediction is accurate and current. This study aims to externally validate two prediction models, the Trauma and Injury Severity Score model developed using the Major Trauma Outcome Study in North America (MTOS-TRISS model), and the NTrD-TRISS model, which is a refined MTOS-TRISS model with coefficients derived from the Malaysian National Trauma Database (NTrD), by regarding mortality as the outcome measurement.

METHOD

This retrospective study included patients with major trauma injuries reported to a trauma centre of Hospital Sultanah Aminah over a 6-year period from 2011 and 2017. Model validation was examined using the measures of discrimination and calibration. Discrimination was assessed using the area under the receiver operating characteristic curve (AUC) and 95% confidence interval (CI). The Hosmer-Lemeshow (H-L) goodness-of-fit test was used to examine calibration capabilities. The predictive validity of both MTOS-TRISS and NTrD-TRISS models were further evaluated by incorporating parameters such as the New Injury Severity Scale and the Injury Severity Score.

RESULTS

Total patients of 3788 (3434 blunt and 354 penetrating injuries) with average age of 37 years (standard deviation of 16 years) were included in this study. All MTOS-TRISS and NTrD-TRISS models examined in this study showed adequate discriminative ability with AUCs ranged from 0.86 to 0.89 for patients with blunt trauma mechanism and 0.89 to 0.99 for patients with penetrating trauma mechanism. The H-L goodness-of-fit test indicated the NTrD-TRISS model calibrated as good as the MTOS-TRISS model for patients with blunt trauma mechanism.

CONCLUSION

For patients with blunt trauma mechanism, both the MTOS-TRISS and NTrD-TRISS models showed good discrimination and calibration performances. Discrimination performance for the NTrD-TRISS model was revealed to be as good as the MTOS-TRISS model specifically for patients with penetrating trauma mechanism. Overall, this validation study has ascertained the discrimination and calibration performances of the NTrD-TRISS model to be as good as the MTOS-TRISS model particularly for patients with blunt trauma mechanism.

[National experts consensus on tracheotomy and intubation for burn patients (2018 version)]

Airway edema, stenosis, obstruction and even asphyxia are easy to occur in patients with extensive burn, deep burn of head, face, and neck area, inhalation injuries, etc., which threaten life. Timely tracheotomy and intubation is an important treatment measure, but lack of knowledge and improper handling in some hospitals resulted in airway obstruction. The technique of percutaneous tracheotomy and intubation provides convenience for emergency treatment of critical burns and mass burn. The Chinese Geriatrics Society organized some experts in China to discuss the indications, timing, methods, extubation, and precautions of tracheotomy and intubation for burn patients. The national experts consensus on tracheotomy and intubation for burn patients (2018 version) was written to provide a reference standard for clinical treatment.

[National experts consensus on tracheotomy and intubation for burn patients (2018 version)]

Airway edema, stenosis, obstruction and even asphyxia are easy to occur in patients with extensive burn, deep burn of head, face, and neck area, inhalation injuries, etc., which threaten life. Timely tracheotomy and intubation is an important treatment measure, but lack of knowledge and improper handling in some hospitals resulted in airway obstruction. The technique of percutaneous tracheotomy and intubation provides convenience for emergency treatment of critical burns and mass burn. The Burn and Trauma Branch of Chinese Geriatrics Society organized some experts in China to discuss the indications, timing, methods, extubation, and precautions of tracheotomy and intubation for burn patients. The national experts consensus on tracheotomy and intubation for burn patients (2018 version) was written to provide a reference standard for clinical treatment.

Orbital decompression for thyroid eye disease: methods, outcomes, and complications

PurposeTo determine the safety and effectiveness of orbital decompression for thyroid eye disease (TED) in our unit. To put this in the context of previously published literature.Patients and methodsA retrospective case review of all patients undergoing orbital decompression for TED under the care of one orbital surgeon (SMS) between January 2009 and December 2015. A systematic literature review of orbital decompression for TED.ResultsWithin the reviewed period, 93 orbits of 55 patients underwent decompression surgery for TED. There were 61 lateral (single) wall decompressions, 17 medial one-and-a-half wall, 11 two-and-a-half wall, 2 balanced two wall, and 2 orbital fat only decompressions. For the lateral (single) wall decompressions, mean reduction in exophthalmometry (95% confidence interval (CI) was 4.2 mm (3.7-4.8), for the medial one-and-a-half walls it was 2.9 mm (2.1-3.7), and for the two-and-a-half walls it was 7.6 mm (5.8-9.4). The most common complications were temporary postoperative numbness (29% of lateral decompressions, 17% of other bony decompressions, OR 0.50, 95% CI 0.12-2.11) and new postoperative diplopia (9% of lateral decompressions, 39% of other bony decompressions, OR 6.8, 95% CI 1. 5-30.9). Systematic literature searching showed reduction in exophthalmometry for lateral wall surgery of 3.6-4.8 mm, with new diplopia 0-38% and postoperative numbness 12-50%. For other bony decompressions, reduction in exophthalmometry was 2.5-8.0 mm with new diplopia 0-45% and postoperative numbness up to 52%.ConclusionDiffering approaches to orbital decompression exist. If the correct type of surgery is chosen, then safe, adequate surgical outcomes can be achieved.

Cloning of three genes involved in the flavonoid metabolic pathway and their expression during insect resistance in Pinus massoniana Lamb

Pinus massoniana Lamb. is an important timber and turpentine-producing tree species in China. Dendrolimus punctatus and Dasychira axutha are leaf-eating pests that have harmful effects on P. massoniana production. Few studies have focused on the molecular mechanisms underlying pest resistance in P. massoniana. Based on sequencing analysis of the transcriptomes of insect-resistant P. massoniana, three key genes involved in the flavonoid metabolic pathway were identified in the present study (PmF3H, PmF3'5'H, and PmC4H). Structural domain analysis showed that the PmF3H gene contains typical binding sites for the 2OG-Fe (II) oxygenase superfamily, while PmF3'5'H and PmC4H both contain the cytochrome P450 structural domain, which is specific for P450 enzymes. Phylogenetic analysis showed that each of the three P. massoniana genes, and the homologous genes in gymnosperms, clustered into a group. Expression of these three genes was highest in the stems, and was higher in the insect-resistant P. massoniana varieties than in the controls. The extent of the increased expression in the insect-resistant P. massoniana varieties indicated that these three genes are involved in defense mechanisms against pests in this species. In the insect-resistant varieties, rapid induction of PmF3H increased the levels of PmF3'5'H and PmC4H expression. The enhanced anti-pest capability of the insect-resistant varieties could be related to temperature and humidity. In addition, these results suggest that these three genes maycontribute to the change in flower color during female cone development.

Anyplex II HPV28 detection and Anyplex II HPV HR detection assays are highly concordant with other commercial assays for detection of high-risk HPV genotypes in women with high grade cervical abnormalities

PURPOSE

to evaluate the performance of Anyplex II HPV28 and HPV HR Detection assays against the EuroArray HPV, Cobas 4800 HPV (Cobas), HPV Amplicor (Amp), Linear Array HPV (LA) and Hybrid Capture 2 (HC2) in detection of high-risk HPV (HR-HPV) from liquid-based cervical cytology samples.

METHODS

cervical specimens from 404 women undergoing management of high-grade cytological abnormality were evaluated by Anyplex II HPV28 and HPV HR Detection assays for detection of HR-HPV genotypes and prediction of histologically-confirmed cervical intraepithelial neoplasia grade 2 or higher (≥CIN2). The results were compared to EuroArray, HC2, Cobas, Amp, and LA.

RESULTS

specimens were evaluated from 404 women with an average age of 30 years, including 336 with a histological diagnosis of ≥ CIN2 and 68 with ≤ CIN1. Concordance of HR-HPV detection between Anyplex II HPV28 and other genotyping assays was 94.79 % (κ = 0.84; EuroArray) and 97.27 % (κ = 0.91; LA); and between Anyplex II HPV HR and other HR-HPV detection assays was 86.35 % (κ = 0.62; HC2), 96.03 % (κ = 0.87; Cobas) and 96.77 % (κ = 0.89; Amp). Using HR-HPV detection for prediction of ≥ CIN2 by Anyplex II HPV28 and HPV HR, sensitivity (90.18, 95 % CI 86.48-93.14; 90.77, 95 % CI 87.16-93.65) and specificity (both 67.16, 95 % CI 54.60-78.15) were not significantly different to the other HPV assays tested, with one exception. Both Anyplex assays had significantly higher sensitivity than HC2 (p < 0.0001), with a specificity of 96 % (p > 0.05) of HC2 in this high-risk population.

CONCLUSIONS

both Anyplex II HPV detection assays were concordant with other commercial assays for HR-HPV detection, with comparable sensitivity and specificity for ≥ CIN2 detection.

Compression and flexural strength of bone cement mixed with blood

PURPOSE

To assess the compression and flexural strength of bone cement mixed with 0 ml, 1 ml, or 2 ml of blood.

METHODS

High viscosity polymethyl methacrylate (PMMA) loaded with or without gentamicin was used. Blood was collected from total knee arthroplasty patients. In the same operating room, one pack of cement each was mixed with 0 ml (control), 1 ml, or 2 ml of blood for 1 minute during the dough phase. The dough was extruded into cylindrical and rectangular moulds for 20 minutes of setting, and then cured in phosphate buffered saline at 37±1ºC for 7 days. The samples were visually inspected for fractures and areas of weakness, and then scanned using microcomputed tomography. 48 gentamicin-loaded and 59 non-gentamicin-loaded samples mixed with 0 ml (control), 1 ml, or 2 ml of blood were randomised for flexural and compression strength testing; each group had at least 6 samples.

RESULTS

In samples loaded with or without gentamicin, the flexural and compressive strength was highest in controls, followed by samples mixed with 1 ml or 2 ml of blood. In samples mixed with 2 ml of blood, the flexural strength fell below the standard of 50 MPa. In samples mixed with 2 ml of blood and all gentamicin-loaded samples, the compressive strength fell below the standard of 70 MPa. Microcomputed tomography revealed areas of voids and pores indicating the presence of laminations and partitions within.

CONCLUSION

The biomechanical strength of PMMA contaminated with blood may decrease. Precautions such as saline lavage, pack drying the bone, change of gloves, and prompt insertion of the implant should be taken to prevent blood from contaminating bone cement.

EUROarray human papillomavirus (HPV) assay is highly concordant with other commercial assays for detection of high-risk HPV genotypes in women with high grade cervical abnormalities

The purpose of this study was to evaluate the performance of the EUROIMMUN EUROArray HPV genotyping assay against the Roche Cobas 4800, Roche HPV Amplicor, Roche Linear Array and Qiagen Hybrid Capture 2 assays in the detection of high-risk HPV (HR-HPV) from liquid based cervical cytology samples collected from women undergoing follow-up for abnormal cervical cytology results. Cervical specimens from 404 women undergoing management of high-grade cytological abnormality were evaluated by EUROarray HPV for detection of HR-HPV genotypes and prediction of histologically-confirmed cervical intraepithelial neoplasia grade 2 or higher (≥CIN2). The results were compared to Hybrid Capture 2, Cobas 4800 HPV, Amplicor and Linear Array HPV. Positivity for 14 HR-HPV types was 80.0 % for EUROarray (95 % CI; 75.7-83.8 %). Agreement (κ, 95 % CI) between the EUROarray and other HPV tests for detection of HR-HPV was good to very good [Hybrid Capture κ = 0.62 (0.54-0.71); Cobas κ = 0.81 (0.74-0.88); Amplicor κ = 0.68 (0.60-0.77); Linear Array κ = 0.77 (0.70-0.85)]. For detection of HR-HPV, agreement with EUROarray was 87.90 % (Hybrid Capture), 93.58 % (Cobas), 92.84 % (Amplicor) and 92.59 % (Linear Array). Detection of HR-HPV was not significantly different between EUROarray and any other test (p < 0.001). EUROarray was concordant with other assays evaluated for detection of high-risk HPV and showed sensitivity and specificity for detection of ≥ CIN2 of 86 % and 71 %, respectively.

Does pathological fracture affect the rate of local recurrence in patients with a giant cell tumour of bone?: a meta-analysis

We investigated whether the presence of a pathological fracture increased the risk of local recurrence in patients with a giant cell tumour (GCT) of bone. We also assessed if curettage is still an appropriate form of treatment in the presence of a pathological fracture. We conducted a comprehensive review and meta-analysis of papers which reported outcomes in patients with a GCT with and without a pathological fracture at presentation. We computed the odds ratio (OR) of local recurrence in those with and without a pathological fracture. We selected 19 eligible papers for final analysis. This included 3215 patients, of whom 580 (18.0%) had a pathological fracture. The pooled OR for local recurrence between patients with and without a pathological fracture was 1.05 (95% confidence interval (CI) 0.66 to 1.67, p = 0.854). Amongst the subgroup of patients who were treated with curettage, the pooled OR for local recurrence was 1.23 (95% CI 0.75 to 2.01, p = 0.417). A post hoc sample size calculation showed adequate power for both comparisons. There is no difference in local recurrence rates between patients who have a GCT of bone with and without a pathological fracture at the time of presentation. The presence of a pathological fracture should not preclude the decision to perform curettage as carefully selected patients who undergo curettage can have similar outcomes in terms of local recurrence to those without such a fracture.

Restoring the anatomical tibial slope and limb axis may maximise post-operative flexion in posterior-stabilised total knee replacements

The optimal management of the tibial slope in achieving a high flexion angle in posterior-stabilised (PS) total knee replacement (TKR) is not well understood, and most studies evaluating the posterior tibial slope have been conducted on cruciate-retaining TKRs. We analysed pre- and post-operative tibial slope differences, pre- and post-operative coronal knee alignment and post-operative maximum flexion angle in 167 patients undergoing 209 TKRs. The mean pre-operative posterior tibial slope was 8.6° (1.3° to 17°) and post-operatively it was 8.0° (0.1° to 16.7°). Multiple linear regression analysis showed that the absolute difference between pre- and post-operative tibial slope (p < 0.001), post-operative coronal alignment (p = 0.02) and pre-operative range of movement (p < 0.001) predicted post-operative flexion. The variance of change in tibial slope became larger as the post-operative maximum flexion angle decreased. The odds ratio of having a post-operative flexion angle < 100° was 17.6 if the slope change was > 2°. Our data suggest that recreation of the anatomical tibial slope appears to improve maximum flexion after posterior-stabilised TKR, provided coronal alignment has been restored.

Characterisation of TNF block haplotypes affecting the production of TNF and LTA

Polymorphisms in the central major histocompatibility complex (MHC) (particularly TNF and adjacent genes) associate with several immunopathological diseases and with susceptibility to pneumonia. The MHC is characterised by strong linkage disequilibrium (LD), so identification of loci affecting disease must be based on haplotypes. We have defined 31 tumour necrosis factor (TNF) block haplotypes (denoted FV1-31) in Caucasians, Asians and Australian Aboriginals. This study correlates the carriage of TNF block haplotypes with TNF and lymphotoxin alpha (LTA) protein production by peripheral blood mononuclear cells from 205 healthy Caucasian subjects, following in vitro stimulation with Streptococcus pneumoniae (S. pneumoniae; gram-positive bacteria), Escherichia coli (E. coli; gram-negative bacteria) or TNF over 4, 8 and 24 h. Fifteen haplotypes were present at >1%, accounting for 94.5% of the cohort. The haplotypes were grouped into five families based on common alleles. Following stimulation, cells from carriers of the FV10 haplotype (family 2) produced less LTA compared with non-FV10 carriers. Carriers of the FV18 haplotype (family 4) produced more LTA than other donors. Induction of TNF by S. pneumoniae following 24 h stimulation was also greater in donors with FV18. The FV18 haplotype associated with the 44.1 MHC ancestral haplotype (HLA-A2, -C5, -B44, -DRB1*0401 and -DQB1*0301) that has few disease associations. FV16 occurred in the 8.1 MHC haplotype (HLA-A2, B8, DR3) that is associated with multiple immunopathological diseases. FV16 did not affect TNF or LTA levels. The findings suggest that many genetic variations critical in vivo are not effectively modelled by short-term cultures.

Deafness due to haemorrhagic labyrinthitis and a review of relapses in Streptococcus suis meningitis

Deafness is a common and often permanent neurological sequel of Streptococcus (S.) suis meningitis. Suppurative labyrinthitis, rather than direct auditory nerve infection, has been found to be the site responsible for deafness. Neuroimaging is important to localise the site involved in hearing loss and to assess the feasibility of a cochlear implantation. S. suis is very sensitive to penicillin. Although a relapse of S. suis meningitis is uncommon, it can occur despite an adequate duration of appropriate antibiotic therapy. We describe a patient with S. suis meningitis, who developed permanent deafness from haemorrhagic labyrinthitis, as shown on magnetic resonance imaging. She suffered a relapse despite a seven-week course of intravenous antibiotics. A review on six cases of relapse reported in the literature shows that relapses occurred despite two to four weeks of antibiotics being administered to the patients. The clinical implications and treatment of relapse are discussed.

Measurement of semivolatile carbonaceous aerosols and its implications: a review

Measurement of carbonaceous aerosols is complicated by positive and negative artifacts. An organic denuder with high efficiency for removing gaseous organics is an effective approach to eliminate the positive artifact, and it is a precondition for the accurate determination of SVOC by an adsorbent backup filter. Evaluations of different configurations of the organic denuder, and SVOC determined by different denuder-based samplers, both integrated and semi-continuous, are reviewed. A new equation for determination of the denuder efficiency is estimated, considering the efficiency of removing both the gaseous organics that could be adsorbed by the quartz and the gaseous passing through the quartz that could be subsequently adsorbed by the backup adsorbent filter. The origin of OC on the backup quartz filter, behind either quartz or Teflon filter, is quantitatively evaluated by the denuder-based method based on the data published. The backup-OC is shown to be dominated by either gaseous organics passing through the front filter or the evaporated particulate organic carbon depending on the sampling environment.

Singapore general practitioners' awareness of atypical features in early Parkinson's disease

INTRODUCTION

Parkinson's disease (PD) accounts for 75 percent of cases with parkinsonism. 25 percent of parkinsonian patients have alternative and possibly treatable conditions. Early intervention of these conditions lies in the physician's awareness and recognition of atypical features in patients presenting with parkinsonism. This survey studies Singapore general practitioners' (GPs) ability to identify atypical features and alternative diagnoses in patients suspected of having early PD.

METHODS

41 out of 57 GPs attending a local symposium participated in a written questionnaire which had the following outcome measures: the ability to identify neurological features that are atypical in early-stage PD; and the awareness of alternative parkinsonian conditions, other than PD.

RESULTS

The mean age of the GPs was 56.0 years (standard deviation [SD] 10.4 years), with 36 males and five females. A mean of 1.6 PD patients were under the care of each GP. Only 33 percent (SD 16 percent) of GPs were aware of atypical features in early PD. If the early atypical feature was one that may occur in late-stage PD, the GPs' awareness was even lower at 19 percent (SD 14 percent). 32 percent of GPs were unable to provide any alternative diagnosis to parkinsonism.

CONCLUSION

This survey suggests a poor level of awareness among Singapore GPs on the identification and presence of alternative parkinsonian conditions. Continuing medical education programmes on PD should emphasise on the diagnostic approach to patients with parkinsonism and the impact of missing the diagnosis of treatable parkinsonian conditions.

Seasonal variation of the particle size distribution of n-alkanes and polycyclic aromatic hydrocarbons (PAHs) in urban aerosol of Guangzhou, China

Seasonal aerosol samples have been collected by Andersen Hi-Vol pumping system equipped with a five stage cascade impactor and a backup filter (size range: 10-7.2 microm, 7.2-3.0 microm, 3.0-1.5 microm, 1.5-0.95 microm, 0.95-0.49 microm, <or=0.49 microm) in the Liwan district, Guangzhou. n-Alkanes were measured using gas chromatography and PAHs were measured using gas chromatography/mass spectrometry analysis. The bimodal log-normal distributions of n-alkanes and semi-volatile PAHs were found, while for non-volatile PAHs that was unimodal, so much as the mode of semi-volatile PAHs was similar with that of the particles. The n-alkanes and PAHs were preferably associated with fine particles. C (max) (carbon number maximum) (C(22)-C(26)), CPI (carbon preference index) (1.12-1.21), U/R (unresolved to resolved components ratio) (7.42-10.7), wax% (0.9-3.12%) and the diagnostic ratios for PAHs revealed that vehicular emission was the major source of these organic compounds during the study periods, while the contribution of epicuticular waxes emitted by terrestrial plants was minor. CPI(2) (values for petrogenic hydrocarbons), CPI(3) (values for biogenic n-alkanes) and wax% revealed that the natural preferentially accumulated in the larger aerosol while the anthropogenic in the smaller. In addition, the different MMDs (mass median diameters) for n-alkanes and PAHs were observed in different seasons. The MMDs for n-alkanes and PAHs were higher in autumn/winter than those in spring/summer. The seasonal effect was related to the hydrocarbon content in the individual particulate fractions, showing a preferential association of n-alkanes and PAHs with larger particles in the autumn/winter season.

Cloned piglets born after nuclear transplantation of embryonic blastomeres into porcine oocytes matured in vivo

Nuclear transplantation in the pig is more difficult than in other domestic animals and only one embryonic nuclear transplantation (NT) pig has been born to date. In this study, reconstituted porcine embryos were produced by electrofusion of blastomeres from in vivo four-cell embryos to enucleated in vivo or in vitro matured (IVM) oocytes. Nuclear transfer using cumulus cells as nuclear donors was also conducted. When blastomeres were used as donors, the electrofusion rate was significantly higher in oocytes matured in vivo (91.5%) than in those matured in vitro (66.1%) (p < 0.01). After fusion, the NT embryos reconstituted from in vivo matured oocytes developed to blastocysts at a rate of 10.3% after culture in rabbit oviducts for up to 5 days, while only 5.9% of the NT embryos reconstructed from in vitro matured oocytes developed to blastocyst stage. Electrofusion rate of cumulus cell nuclei with enucleated IVM oocytes was lower (47.6%) and only 1.5% (2/136) of the reconstituted eggs developed in vitro to morula stage, and 1.9% developed to blastocysts when cultured in the ligated rabbit oviducts. Transfer of 94 embryos reconstructed by blastomere NT with in vivo matured oocytes to five synchronous recipients resulted in the birth of two cloned piglets. No piglet was born following transfer to two recipients of embryos (n = 39) derived from NT with in vitro matured oocytes. The results demonstrate that in vivo matured oocytes are better recipients than those matured in vitro for pig cloning.

Paraneoplastic progressive supranuclear palsy syndrome in a patient with B-cell lymphoma

An important component in the diagnosis of atypical parkinsonian disorders is the exclusion of secondary causes. Paraneoplastic causes of parkinsonism are extremely rare. We describe a case which presented initially as probable progressive supranuclear palsy (PSP) but on follow-up displayed a rapidly progressive course, unexplained fever, peripheral neuropathy and an abnormal CSF. We highlight the difficulties faced in formulating a diagnosis for this unusual case prior to the discovery of an occult B-cell lymphoma, and discuss its relevance in the exclusion criteria for PSP. A paraneoplastic cause should be considered if disease progression is unusually rapid.

Studies of the cell cycle of in vitro cultured skin fibroblasts in goats: work in progress

The effect of serum starvation and olomoucine treatment on the cell cycle and apoptosis of goat skin fibroblasts cultured in vitro is reported in this paper. The cells were obtained from the ear of a female goat 1.5 years of age. Analysis of cell cycle distribution by fluorescence-activated cell sorting (FACS) showed that 3.4, 60.8 and 15.1% of normally cycling cells were at G1, G0 and S phase, respectively. Serum starvation for 1, 3 and 5 days arrested 70.1, 70.2 and 83.4% cells, respectively, at G0/G1 phase. Seventy-eight percent of confluent cells were at G0/G1 stage, but in contrast to the serum starved group, this high percentage of G0/G1 cells was mainly associated with G1 cells. Of cells not deprived of serum, 73.6% were arrested at G1/G0 when treated with 100 microM olomoucine for 9 h compared to 85.5% of cells that had been starved of serum for 2 days (co-inhibition) (P<0.01). After co-inhibition, 45% of cells entered S phase when re-cultured in normal medium for 5 h, indicating that the inhibition was reversible. Under normal culture conditions, 1.2% of cells underwent apoptosis. Serum starvation for 1, 2, 3, 5 and 10 days caused apoptosis in 1.7, 3.9, 4.5, 11.7 and 90.3% of cells, respectively. Treatment with 100 microM olomoucine for 9h did not increase the number of apoptotic cells significantly (1.9%, P>0.05). When cells were co-inhibited, 4.1% of cells underwent apoptosis. In conclusion, although serum withdrawal for 5 days or more effectively arrested cells at G0/G1 stages, it increased apoptosis of cells significantly. However, co-inhibition by serum withdrawal and olomoucine treatment was found to be an appropriate treatment to obtain more healthy G0/G1 cells based on the low percentage of apoptotic cells after treatment.

Effects of pregnant mare serum gonadotropin (eCG) on follicle development and granulosa-cell apoptosis in the pig

The effect of eCG on follicular development and granulosa-cell apoptosis in sexually mature and immature gilts and on granulosa-cell apoptosis in vitro were studied. The sexually mature gilts were treated with eCG on Day 11 of the estrous cycle, and effects were analyzed at different times after treatment with untreated animals at corresponding stages of the cycle as controls. Apoptosis was determined by terminal deoxynucleotidyl transferase-mediated dUTP nick end labeling (TUNEL), hematoxylin and eosin staining, and DNA ladder. The proportion of apoptotic cells in atretic follicles (39%) was significantly higher (P<0.01) than that in healthy follicles (9%). At 24h after eCG treatment in mature gilts, the total number of follicles visible on the ovarian surface (57 per ovary), the number of small (<3mm) follicles (31.5 per ovary) and the number of medium-sized (3-5mm) follicles (23 per ovary) were significantly higher (P<0.05) than those of control animals (28, 20 and 6.5 per ovary, respectively), and declined gradually thereafter to below the level of control animals. The number of large (>or=5mm) follicles began to show a marked increase at 72h after eCG (8.5 versus 2.5, P<0.05). At 24h after eCG treatment, the proportions of apoptotic cells in small (7.2%) and medium-sized follicles (7.4%) were markedly lower (P<0.01) than those in controls (21.5 and 21%, respectively) and increased gradually thereafter to approach the level in controls. The percentage of apoptotic cells in large follicles (10% at 24h post-eCG) did not change significantly. Before eCG treatment, there were markedly fewer follicles of all types on ovaries of immature gilts than of mature gilts (9 versus 25 per ovary) and the proportion of apoptotic cells in small and medium follicles was high (25 and 34%, respectively). After eCG treatment, the changes in follicle number and proportion of apoptotic cells in the immature gilts followed a similar pattern to that of the mature gilts. Equine chorion gonadotropin inhibited apoptosis of granulosa cells cultured either in vitro or in intact follicles in a dose-dependent manner. Thus, follicular atresia in the pig, as in other animals, was characterized by apoptosis of large numbers of granulosa cells, and eCG promoted follicular development by inhibition of granulosa-cell apoptosis.

In vitro spontaneous parthenogenetic activation of golden hamster oocytes

Parthenogenetic activation is a major hurdle to be cleared for the examination of the human sperm chromosome after intracytoplasmic injection (ICSI) into golden hamster oocytes. Various factors that affect spontaneous activation of hamster oocytes were, therefore, investigated in this study. We collected cumulus-oocyte complexes (COC) from the oviducts of superovulated females and washed them thoroughly with Ca2+-containing or Ca2+-free TALP-HEPES medium (handling media). We cultured oocytes with intact cumulus or those without cumulus (removed by previous hyaluronidase treatment) in Ca2+-containing or -free m-TALP-3 for 6 or 12 h before examining for their activation. Among the oocytes recovered 17 h post-hCG, 92-94% were parthenogenetically activated by 6 h of in vitro culture. Activation rate in the oocytes collected at 13.5 h post-hCG (53%) was significantly (P < 0.05) lower than that in the oocytes collected 17 h post-hCG (92%), indicating that the spontaneous activation rate increased as the oocytes became older. Both cumulus-intact and cumulus-free oocytes had similar (P > 0.05) activation rates when cultured in vitro, suggesting that hyaluronidase treatment had no effect on the rate of oocyte activation. Omission of Ca2+ from the handling medium also had no effect on the activation of the oocytes. The rate of spontaneous activation of the oocytes cultured in calcium-free medium for 6 (9%) and 12 h (16%) was significantly (P < 0.01) lower than that (94%) of the control oocytes cultured in Ca2+-containing medium, implying a positive influence of Ca2+ on in vitro activation of hamster oocytes. When we cultured the oocytes first in calcium-free medium for 6 h, and then in calcium-containing medium for 6 h, 94% were activated, which is comparable to the rate for oocytes continuously cultured in Ca2+-containing medium. This indicates that the inhibition of hamster oocyte activation in Ca2+-free medium is reversible and can be used to control spontaneous activation of golden hamster oocytes.

Polymerized Liposome Assemblies: Bifunctional Macromolecular Selectin Inhibitors Mimicking Physiological Selectin Ligands

Monomeric sialyl Lewis(X) (sLe(x)) and sLe(x)-like oligosaccharides are minimal structures capable of supporting selectin binding in vitro. However, their weak binding interactions do not correlate with the high-affinity binding interactions witnessed in vivo. The polyvalent display of carbohydrate groups found on cell surface glycoprotein structures may contribute to the enhanced binding strength of selectin-mediated adhesion. Detailed biochemical analyses of physiological selectin ligands have revealed a complicated composition of molecules that bind to the selectins in vivo and suggest that there are other requirements for tight binding beyond simple carbohydrate multimerization. In an effort to mimic the high-affinity binding, polyvalent scaffolds that contain multicomponent displays of selectin-binding ligands have been synthesized. Here, we demonstrate that the presentation of additional anionic functional groups in the form of sulfate esters, on a polymerized liposome surface containing a multimeric array of sLe(x)-like oligosaccharides, generates a highly potent, bifunctional macromolecular assembly. This assembly inhibits L-, E-, and P-selectin binding to GlyCAM-1, a physiological ligand better than sLe(x)-like liposomes without additional anionic charge. These multivalent arrays are 4 orders of magnitude better than the monovalent carbohydrate. Liposomes displaying 3'-sulfo Lewis(X)-like oligosaccharides, on the other hand, show slight loss of binding with introduction of additional anionic functional groups for E- and P-selectin and negligible change for L-selectin. The ability to rapidly and systematically vary the composition of these assemblies is a distinguishing feature of this methodology and may be applied to the study of other systems where composite binding determinants are important for high-affinity binding.

Familial autoimmune myasthenia gravis

Familial Autoimmune Myasthenia Gravis (FAMG) is rarely reported. We present a mother and son with late-onset mild to moderate ocular disease, low acetylcholine receptor antibody titre and the absence of a thymoma. Both responded well to low doses of anticholinesterase. HLA typing revealed that they did not share the usual HLA antigens or haplotypes with that previously reported in Caucasian and Chinese sporadic Myasthenia Gravis. Chinese FAMG may be associated with HLA antigens different from that of sporadic MG.

Wernicke's encephalopathy in patients with hyperemesis gravidarum

Our two patients presented with Wernicke's Encephalopathy (WE) resulting from prolonged hyperemesis gravidarum. This is an unusual cause of WE, a potentially fatal medical emergency due to thiamine deficiency. We discuss the clinical settings, presentation, diagnosis, neurophysiological and radiological findings, treatment and outcome of WE in these two cases and the neuropathologic correlation of this condition. We stress upon the importance of early diagnosis and prompt treatment of WE.

The bZIP-like motif of hnRNP C directs the nuclear accumulation of pre-mRNA and lethality in yeast

The hnRNP C protein tetramer cooperatively binds 230 nt increments of pre-mRNA in vitro in a salt-resistant manner and is located along the length of vertebrate transcripts in vivo. Based on these and other findings it has been suggested that hnRNP C functions as a chaperonin to maintain long lengths of RNA topologically single-stranded and accessible to splicing factors. We report here that human C protein is lethal when expressed in the yeast Saccharomyces cerevisiae. Through a series of fluorescent immunolocalization studies, lethality was observed to be associated with the rapid nuclear accumulation of both C protein and yeast pre-mRNA. Studies using various protein constructs and the two hybrid assay reveal that these events are dependent on the basic 40 residue high-affinity RNA binding domain and its contiguous leucine zipper-like motif (the bZLM, residues 140-214). Additionally, equilibrium binding studies have shown that the bZLM is the determinant of C protein's salt-resistant RNA binding mode. Taken together, these findings further distinguish the bZIP-like domain as the major determinant of C protein's high-affinity interaction with RNA, oligomerization, and its highly cooperative RNA binding activity. Finally, these findings indicate that yeast and vertebrates may possess a conserved mechanism for general import of RNP although a true homolog to vertebrate C protein appears not to exist in yeast. Lethality is likely due to the absence in yeast of specific mechanisms for the removal of human C protein from nascent transcripts.

Interaction of lidocaine with the cardiac sodium channel: effects of low extracellular pH are consistent with an external blocking site

Brief extracellular application of millimolar concentrations of lidocaine affected sodium currents recorded in isolated rat ventricular myocytes in two ways: 1) a reduction of the maximum current consistent with a channel blocking action, and 2) a negative shift in the voltage dependence of inactivation consistent with an interaction with the inactivated state of the channel. Both effects occurred very rapidly (<< 1 s). Decreasing extracellular pH to 6.4 increased the potency for channel block (EC50 1.8 +/- 0.2 mM at pH 7.4 and 0.8 +/- 0.1 mM at pH 6.5) and decreased the potency to shift inactivation (V(1/2) shift -42 mV by 1 mM lidocaine at pH 7.4 and -12.6 mV at pH 6.5). Channel block was slightly less at +90 mV compared to -40 mV at either pH (not statistically significant). The increase in potency for block at decreased extracellular pH, while intracellular pH is buffered, and the lack of voltage dependence of block, suggest that the charged form of lidocaine can block the channel by interacting with a site near the extracellular mouth, although alternative explanations are discussed.

Leukemia inhibitory factor, leukemia inhibitory factor receptor, and glycoprotein 130 in rhesus monkey uterus during menstrual cycle and early pregnancy

This goal of this study was to examine immunohistochemical distribution of leukemia inhibitory factor (LIF), LIF receptor (LIFR), and glycoprotein (gp) 130 in rhesus monkey uterus during the menstrual cycle and early pregnancy. Pregnancy rate was significantly reduced in the control group from 66.7% (12 of 18) to 22.2% (4 of 18) with an injection of goat anti-human recombinant LIF immunoglobulin G into the uterine lumen on Day 8 of pregnancy. LIF was mainly localized in glandular and luminal epithelium. LIF immunostaining during the luteal phase was stronger than it was during the proliferative phase. LIF staining gradually increased from Day 3 of pregnancy and reached its highest level on Day 9. LIFR was mainly localized in the glandular and luminal epithelium. LIFR staining during the luteal phase was stronger than it was during the proliferative phase. LIFR staining began to increase from Day 3 of pregnancy and reached a high level on Days 9 and 11. Gp130, a signal-transducing receptor component of LIF, was mainly localized in the glandular epithelium. A high level of gp130 was found on Days 16 and 20 of menstrual cycle, and from Days 5 to 11 of pregnancy. These results suggest that LIF may play an important role in monkey implantation, as it does in mice.

Effect of age on immunocytochemical staining characteristics of adenohypophyseal cells in Mongolian pony mares and stallions

OBJECTIVE

To determine the effect of age on immunocytochemical staining characteristics of adenohypophyseal cells of Mongolian pony mares and stallions.

ANIMALS

35 Mongolian ponies.

PROCEDURE

Pituitary glands from 1- to 22-year-old horses of both sexes were collected at a commercial slaughterhouse in China and allocated into 7 groups according to age and sex: prepubertal stallions (n = 5; 1 to 2 years old), young stallions (6; 3 to 7 years old), middle-aged stallions (4; 10 to 12 years old), old stallions (5; 15 to 22 years old), young mares (3; 3 to 7 years old), middle-aged mares (5; 10 to 12 years old), and old mares (7; 15 to 22 years old). Pituitary glands were processed for microscopy, and sections were immunocytochemically stained for various pituitary hormones. The percentages and cell areas of 6 types of adenohypophyseal cells were determined by use of morphometry.

RESULTS

Age-related alterations in adenohypophyseal cells were detected in horses > 15 years old. Percentage of somatotrophs decreased with age regardless of sex, and percentage of lactotrophs increased with age in stallions. In old mares, percentage of follicle-stimulating hormone cells increased, whereas cell area of follicle-stimulating hormone and luteinizing hormone cells decreased. Differences between sexes for percentage of somatotrophs and lactotrophs, and cell area of follicle-stimulating hormone and luteinizing hormone cells were not evident in old horses.

CONCLUSIONS AND CLINICAL RELEVANCE

Differences among percentages and cell areas of pituitary cell types in old horses may be associated with degeneration of the sex organs.

Does preservative-free lignocaine 1% for hydrodissection reduce pain during phacoemulsification?

PURPOSE

To compare preservative-free 1% lignocaine with balanced salt solution (BSS) in alleviating pain during hydrodissection in phacoemulsification cataract surgery.

SETTING

West Norwich Hospital, Norfolk, United Kingdom.

METHODS

This prospective double-masked trial comprised 68 patients having day-case phacoemulsification cataract surgery. Patients were randomly divided into 2 groups, receiving either BSS or lignocaine 1% solution for hydrodissection during routine uneventful phacoemulsification using topical anesthesia. The level of intraoperative pain was scored on a scale of 0 (no pain) to 10 (severe pain), and the scores between the 2 groups were compared.

RESULTS

Of the 68 patients, 33 (49%) received BSS and 35 (51%), lignocaine 1% solution. A pain score greater than 2 was considered clinically significant; 28 patients (85%) in the BSS group and 25 (71%) in the lignocaine 1% group scored 2 or less. The chi-square and Mann-Whitney tests found no significant difference between the BSS and lignocaine 1% groups (P = .30 and P = .432, respectively).

CONCLUSION

There was no significant difference in the pain scores in patients who received BSS or lignocaine 1% solution. Thus, we conclude that hydrodissecting with lignocaine 1% solution does not provide added pain relief during phacoemulsification.

Nuclear matrix-like filaments and fibrogranular complexes form through the rearrangement of specific nuclear ribonucleoproteins

The behavior of nuclear pre-mRNA-binding proteins after their nuclease and/or salt-induced release from RNA was investigated. After RNase digestion or salt extraction, two proteins that initially exist as tetramers (A2)(3)B1 in isolated heterogeneous nuclear ribonucleoprotein (hnRNP) complexes quantitatively reassociated to form regular helical filaments ranging in length from 100 nm to >10 microm. In highly magnified preparations prepared for scanning transmission electron microscopy, single filaments have diameters near 18 nm. In conventional negatively stained preparations viewed at low magnification, the diameters of the thinnest filaments range from 7 to 10 nm. At protein concentrations of >0.1 mg/ml, the filaments rapidly aggregated to form thicker filamentous networks that look like the fibrogranular structures termed the "nuclear matrix." Like the residual material seen in nuclear matrix preparations, the hnRNP filaments were insoluble in 2 M NaCl. Filament formation is associated with, and may be dependent on, disulfide bridge formation between the hnRNP proteins. The reducing agent 2-mercaptoethanol significantly attenuates filament assembly, and the residual material that forms is ultrastructurally distinct from the 7- to 10-nm fibers. In addition to the protein rearrangement leading to filament formation, nearly one-third of the protein present in chromatin-clarified nuclear extracts was converted to salt-insoluble material within 1 min of digestion with RNase. These observations are consistent with the possibility that the residual material termed the nuclear matrix may be enriched in, if not formed by, denatured proteins that function in pre-mRNA packaging, processing, and transport.

Phacoemulsification cataract surgery: is routine review necessary on the first post-operative day?

PURPOSE

To determine the value of routine review on the first post-operative day following phacoemulsification cataract surgery.

METHODS

A prospective study was performed of 238 consecutive patients who underwent phacoemulsification cataract surgery. Local anaesthesia was used for 97% of patients and surgery was performed as a day-case procedure for 93% of patients. The findings at the first day post-operative review were analysed separately for patients who had undergone uncomplicated surgery and patients who had suffered an intraoperative complication. Four patients were excluded because of incomplete data collection.

RESULTS

A total of 227 patients underwent uncomplicated phacoemulsification cataract surgery. Thirteen (5.7%, 95% confidence interval (CI) 3.1-9.6%) of these were found to have post-operative complications at their first day review which comprised corneal oedema (4.4%, 95% CI 2.1-8.0%), raised intraocular pressure > or = 30 mmHg (1.3%, 95% CI 0.3-3.8%), hyphaema (0.9%, 95% CI 0.1-3.1%), corneal abrasion (0.4%, 95% CI 0.0-2.4%) and anterior uveitis (0.4%, 95% CI 0.0-2.4%). These findings led to the standard post-operative management being altered for 5 (2.2%) patients. Intraoperative complications occurred in 7 (2.9%) patients during phacoemulsification cataract surgery. Five (71%) of these patients had post-operative complications at their first day review.

CONCLUSIONS

Routine review on the first post-operative day following uncomplicated phacoemulsification cataract surgery could safely be withdrawn. A single post-operative review at 1-2 weeks after surgery would then be required, supplemented by patient-initiated post-operative review in the interim.