Coronavirus disease 2019 in kidney transplant recipients: a systematic review and meta-analysis

Introduction

The clinical presentation and outcomes of coronavirus disease 2019 (COVID-19) in kidney transplant recipients (KTRs) have not been well studied.

Methods

We performed a meta-analysis to examine the presenting features, outcomes and the effect of treatment on outcomes of KTRs with COVID-19. Database search was performed up to 5 September 2020 through PubMed, Embase, Web of Science, Scopus and CENTRAL.

Results

Overall, 23 studies (1,373 patients) were included in the review and meta-analysis. The most common presenting symptoms included fever (74.0%, 95% confidence interval [CI] 65.3-81.1), cough (63.3%, 95% CI 56.5-69.6) and dyspnoea (47.5%, 95% CI 39.6-55.6). Pooled rates of mortality and critical illness were 21.1% (95% CI 15.3-28.4) and 27.7% (95% CI 21.5-34.8), respectively. Acute kidney injury occurred in 38.9% (95% CI 30.6-48.1) and dialysis was required in 12.4% (95% CI 8.3-18.0) of the cases.

Conclusion

Kidney transplant recipients with COVID-19 have a similar clinical presentation as the general population, but they have higher morbidity and mortality. It is uncertain whether high-dose corticosteroid or hydroxychloroquine reduces the risks of mortality in KTRs with COVID-19.

P–547 Single-cell RNA sequencing identifies molecular regulations associated with poor maturation performance on rescue in vitro matured oocytes

Study question

What is the transcriptome signature associated with rescuein vitro matured (rIVM) oocytes?

Summary answer

GATA–1/CREB1/WNT signaling axis was repressed in rIVM oocytes of poor quality.

What is known already

rIVM aims to produce mature oocytes (MII) for in vitro fertilization (IVF) through IVM of immature oocytes collected from stimulated ovaries. It is less popular due to limited success rate in infertility treatment. Genetic aberrations, cellular stress, and the absence of cumulus cell support in oocytes could account for the failure of rIVM.

Study design, size, duration

We applied single-cell RNA sequencing (scRNA-seq) to capture the transcriptomes of human in vivo (IVO) oocytes (n = 10) from 7 donors and rIVM oocytes (n = 10) from 10 donors, followed by studying the maternal age effect and ovarian responses on rIVM oocyte transcriptomes.

Participants/materials, setting, methods

Human oocytes were collected from donors aged 28–41 years with a body mass index of < 30. RNA extraction, cDNA generation, library construction and sequencing were performed in one preparation. scRNA-seq data were then processed and analyzed. Selected genes in therIVM vs. IVO comparison were validated by quantitative real-time PCR.

Main results and the role of chance

The transcriptome profiles of rIVM/IVO showed distinctive differences. A total of 1559 differentially expressed genes (DEGs, genes with at least two-fold change and adjusted p < 0.05) were found to be enriched in metabolic processes, biosynthesis, and oxidative phosphorylation. Among these DEGs, we identified a repression of WNT/β-catenin signaling in rIVM when compared with IVO oocytes. We found that estradiol level exhibited a significant age-independent correlation with the IVO mature oocyte ratio (MII ratio). rIVM oocytes with higher MII ratio showed over-represented cellular processes such as anti-apoptosis. To further identify targets that contribute to the poor outcomes of rIVM, we compared oocytes collected from young donors with high MII ratio versus donors of advanced maternal age and revealed CREB1was an important regulator in rIVM. Our study identified GATA–1/CREB1/WNT signaling was repressed in both rIVM condition and rIVM oocytes of low-quality.

Limitations, reasons for caution

In the rIVM oocytes of high- and low-quality comparison, the number of samples was limited after data filtering with stringent selection criteria. For the oocyte stage identification, we were unable to predict the presence of oocyte spindle so polar body extrusion was the only indicator.

Wider implications of the findings: This study showed that GATA–1/CREB1/WNT signaling and antioxidant actions were repressed in rIVM condition and was further downregulated in rIVM oocytes of low-quality, providing us the foundation of subsequent follow-up research on human subjects.

Trial registration number

Not applicable

Single-cell RNA sequencing identifies molecular targets associated with poor in vitro maturation performance of oocytes collected from ovarian stimulation

STUDY QUESTION

What is the transcriptome signature associated with poor performance of rescue IVM (rIVM) oocytes and how can we rejuvenate them?

SUMMARY ANSWER

The GATA-1/CREB1/WNT signalling axis was repressed in rIVM oocytes, particularly those of poor quality; restoration of this axis may produce more usable rIVM oocytes.

WHAT IS KNOWN ALREADY

rIVM aims to produce mature oocytes (MII) for IVF through IVM of immature oocytes collected from stimulated ovaries. It is not popular due to limited success rate in infertility treatment. Genetic aberrations, cellular stress and the absence of cumulus cell support in oocytes could account for the failure of rIVM.

STUDY DESIGN, SIZE, DURATION

We applied single-cell RNA sequencing (scRNA-seq) to capture the transcriptomes of human in vivo oocytes (IVO) (n = 10) from 7 donors and rIVM oocytes (n = 10) from 10 donors. The effects of maternal age and ovarian responses on rIVM oocyte transcriptomes were also studied. In parallel, we studied the effect of gallic acid on the maturation rate of mouse oocytes cultured in IVM medium with (n = 84) and without (n = 85) gallic acid.

PARTICIPANTS/MATERIALS, SETTING, METHODS

Human oocytes were collected from donors aged 28-41 years with a body mass index of <30. RNA extraction, cDNA generation, library construction and sequencing were performed in one preparation. scRNA-seq data were then processed and analysed. Selected genes in the rIVM versus IVO comparison were validated by quantitative real-time PCR. For the gallic acid study, we collected immature oocytes from 5-month-old mice and studied the effect of 10-μM gallic acid on their maturation rate.

MAIN RESULTS AND THE ROLE OF CHANCE

The transcriptome profiles of rIVM/IVO oocytes showed distinctive differences. A total of 1559 differentially expressed genes (DEGs, genes with at least 2-fold change and adjusted P < 0.05) were found to be enriched in metabolic processes, biosynthesis and oxidative phosphorylation. Among these DEGs, we identified a repression of WNT/β-catenin signalling in rIVM when compared with IVO oocytes. We found that oestradiol levels exhibited a significant age-independent correlation with the IVO mature oocyte ratio (MII ratio) for each donor. rIVM oocytes from women with a high MII ratio were found to have over-represented cellular processes such as anti-apoptosis. To further identify targets that contribute to the poor clinical outcomes of rIVM, we compared oocytes collected from young donors with a high MII ratio with oocytes from donors of advanced maternal age and lower MII ratio, and revealed that CREB1 is an important regulator. Thus, our study identified that GATA-1/CREB1/WNT signalling was repressed in both rIVM oocytes versus IVO oocytes and in rIVM oocytes of lower versus higher quality. Consequently we investigated gallic acid, as a potential antioxidant substrate in human rIVM medium, and found that it increased the mouse oocyte maturation rate by 31.1%.

LARGE SCALE DATA

Raw data from this study can be accessed through GSE158539.

LIMITATIONS, REASONS FOR CAUTION

In the rIVM oocytes of the high- and low-quality comparison, the number of samples was limited after data filtering with stringent selection criteria. For the oocyte stage identification, we were unable to predict the presence of oocyte spindle, so polar body extrusion was the only indicator.

WIDER IMPLICATIONS OF THE FINDINGS

This study showed that GATA-1/CREB1/WNT signalling was repressed in rIVM oocytes compared with IVO oocytes and was further downregulated in low-quality rIVM oocytes, providing us the foundation of subsequent follow-up research on human oocytes and raising safety concerns about the clinical use of rescued oocytes.

STUDY FUNDING/COMPETING INTEREST(S)

This work was supported by the Collaborative Research Fund, Research Grants Council, C4054-16G, and Research Committee Funding (Research Sustainability of Major RGC Funding Schemes), The Chinese University of Hong Kong. The authors have no conflicts of interest to declare.

Assessment of risk factors contributing to carcass bruising in fed cattle at commercial slaughter facilities

Cattle injuries can occur during transportation due to vehicle design, transport conditions, and loading or unloading procedures and lead to carcass bruising and economic loss due to decreased carcass value. The objectives of this study were to determine whether a relationship exists between trauma incurred during unloading and prevalence of carcass bruising in finished beef cattle at commercial slaughter facilities and determine related risk factors which contribute to both trauma and carcass bruising. Breed (classified as either Holstein cattle or beef breeds), sex, distance traveled, and trailer type (“fat/feeder combination” vs. “fat” trailer) were considered risk factors which may contribute to traumatic event prevalence. When carcass bruise prevalence within each lot was used as the dependent variable, breed, sex, distance traveled, traumatic event prevalence, ribeye area, fat thickness, yield grade, and average carcass weight were considered potential risk factors. Carcass bruises were categorized by location and size, according to the Harvest Audit Program Carcass Bruise Scoring System. Traumatic events were observed while cattle exited trailers onto the unloading docks, and were categorized by location on the animal. Average traumatic event prevalence per lot was 20.4% (± 1.11%). Average carcass bruise prevalence by lot was 68.2% (± 1.15%). There was an interaction between breed and trailer type when multiple linear regression was used to explore variables contributing to traumatic events observed at unloading (P ≤ 0.05). Traumatic events were not associated with prevalence of carcass bruising, while average carcass weight and breed were associated with carcass bruising prevalence. Carcass bruising was more prevalent in Holstein cattle than in cattle which were predominantly beef breeds (P ≤ 0.01). Average carcass weight was negatively associated with carcass bruise prevalence (P ≤ 0.05). The association between traumatic events at unloading and carcass bruising is not significant when multiple variables are considered, indicating that bruising may occur at numerous other points prior to and during the transportation process, including loading and transport, and that other variables can contribute to carcass bruise prevalence. These areas should be explored to determine all potential causes of bruising in beef carcasses, and to help implement prevention practices.

Association of CD247 with systemic lupus erythematosus in Asian populations

OBJECTIVE

Systemic lupus erythematosus (SLE) is a prototypic autoimmune disease with complex genetic inheritance. CD247 (CD3Z, TCRZ) plays a vital role in antigen recognition and signal transduction in antigen-specific immune responses, and is known to be involved in SLE pathogenesis. Weak disease association was reported for genetic variants in this gene in Caucasian studies for SLE, Crohn's disease and systemic sclerosis, but its role as a genetic risk factor was never firmly established.

METHODS

In this study, using a collection of 612 SLE patients and 2193 controls of Chinese ethnicity living in Hong Kong in a genome-wide study, single nucleotide polymorphisms (SNPs) in and around CD247 were identified as being associated with SLE. The two most significant SNPs in this locus were selected for further replication using TaqMan genotyping assay in 3339 Asian patients from Hong Kong, Mainland China, and Thailand, as well as 4737 ethnically and geographically matched controls.

RESULTS

The association of CD247 with SLE in Asian populations was confirmed (rs704853: odds ratio [OR] = 0. 81, p = 2.47 × 10(-7); rs858543: OR = 1.10, p = 0.0048). Patient-only analysis suggested that rs704853 is also linked to oral ulcers, hematologic disorders and anti-double-stranded DNA (dsDNA) antibody production.

CONCLUSION

A significant association between variants in CD247 and SLE was demonstrated in Asian populations. Understanding the involvement of CD247 in SLE may shed new light on disease mechanisms and development of new treatment paradigms.

Demonstration of ignition radiation temperatures in indirect-drive inertial confinement fusion hohlraums

We demonstrate the hohlraum radiation temperature and symmetry required for ignition-scale inertial confinement fusion capsule implosions. Cryogenic gas-filled hohlraums with 2.2 mm-diameter capsules are heated with unprecedented laser energies of 1.2 MJ delivered by 192 ultraviolet laser beams on the National Ignition Facility. Laser backscatter measurements show that these hohlraums absorb 87% to 91% of the incident laser power resulting in peak radiation temperatures of T(RAD)=300 eV and a symmetric implosion to a 100 μm diameter hot core.

D-serine regulation: a possible therapeutic approach for central nervous diseases and chronic pain

D-Serine, an endogenous modulator of NMDA receptors has been shown to play a vital role in many neuropsychiatric functions such as learning, memory, nociception and implicated in pathological conditions like schizophrenia and Alzheimer's disease. We propose possible therapeutic approaches for some CNS diseases and chronic pain, targeting the D-serine levels by manipulating its uptake, biosynthesis and metabolism.

Association of BANK1 and TNFSF4 with systemic lupus erythematosus in Hong Kong Chinese

Systemic lupus erythematosus (SLE) is a prototypic autoimmune disease with complex genetic inheritance. Recently, single nucleotide polymorphisms (SNPs) in BANK1 and TNFSF4 have been shown to be associated with SLE in Caucasian populations, but it is not known whether they are also involved in the disease in other ethnic groups. Recent data from our genome-wide association study (GWAS) for 314 SLE cases and 920 controls collected in Hong Kong identified SNPs in and around BANK1 and TNFSF4 to be associated with SLE risk. On the basis of the results of the reported studies and our GWAS, SNPs were selected for further genotyping in 949 SLE patients (overlapping with the 314 cases in our GWAS) and non-overlapping 1042 healthy controls. We confirmed the associations of BANK1 and TNFSF4 with SLE in Chinese (BANK1, rs3733197, odds ratio (OR)=0.84, P=0.021; BANK1, rs17266594, OR=0.61, P=4.67 x 10(-9); TNFSF4, rs844648, OR=1.22, P=2.47 x 10(-3); TNFSF4, rs2205960, OR=1.30, P=2.41 x 10(-4)). Another SNP located in intron 1 of BANK1, rs4522865, was separately replicated by Sequenom in 360 cases and 360 controls and was also confirmed to be associated with SLE (OR=0.725, P=2.93 x 10(-3)). Logistic regression analysis showed that rs3733197 (A383T in ankyrin domain) and rs17266594 (a branch point-site SNP) from BANK1 had independent contributions towards the disease association (P=0.037 and 6.63 x 10(-8), respectively). In TNFSF4, rs2205960 was associated with SLE independently from the effect of rs844648 (P=6.26 x 10(-3)), but not vice versa (P=0.55). These findings suggest that multiple independent genetic variants may be present within the gene locus, which exert their effects on SLE pathogenesis through different mechanisms.

Risk factors and mortality predictors of hepatic veno-occlusive disease after pediatric hematopoietic stem cell transplantation

A cohort of 138 children with 144 hematopoietic stem cell transplantation (HSCT) performed in 1997-2006 were analyzed to evaluate risk factors and mortality predictors of hepatic veno-occlusive disease (VOD). Nineteen patients (13.2%) developed VOD (nine boys, median age 3.5 years) at 1-21 days after HSCT (median 13 days). Age < or =2 years at transplant (odds ratio (OR)=5.25, P=0.011), BU-CY conditioning (OR=5.16, P=0.001), thalassemia major (OR=3.97, P=0.015), platelet engraftment beyond day +21 (OR=8.67, P=0.025) were univariate risk factors for VOD. The first two remained significant in multivariate regression. Seven patients (36.8%) with VOD died, at a median of 44 days post transplant (range, 30-421 days). The 5-year survival was 62%. All surviving patients had normal liver function on follow-up at 0.5-9 years. Patients with VOD had higher 100-day mortality (16.3 vs 9.6%, P=0.024). Mortality predictors included donors other than autologous or matched sibling (hazard ratio (HR)=23.6, P=0.006), hepatic and cutaneous GVHD (HR=8.15, P=0.038), maximal weight gain >9% (HR=6.81, P=0.023), pleural effusion, intensive care unit admission, peak bilirubin >300 micromol l(-1) (HR=13.6, P=0.016), day +21 bilirubin >200 micromol l(-1) (HR=33.9, P=0.001), and rise of bilirubin >15 micromol l(-1) per day within the first week (HR=19.8, P=0.006). Mortality was substantially higher if >3 predictors were present (HR=33.9, P=0.001). Meticulous monitoring in high-risk patients and early treatment should be considered before VOD progresses beyond salvage.

Nocistatin attenuated the nociceptin induced c-Fos expression in the mouse hippocampus

Nocistatin and nociceptin/orphaninFQ (N/OFQ) are the two new peptides which may have roles in nociception, memory, anxiety, and other biological functions. Nocistatin acts as a functional antagonist to N/OFQ in several functions, but their neuro-anatomical sites of interaction are unknown. We investigated the effect of combined intracerebroventricular (i.c.v.) injection of nocistatin with N/OFQ, on N/OFQ induced c-Fos expression in the mouse hippocampus, using c-Fos immunohistochemistry. We found that co-injection of nocistatin with N/OFQ significantly attenuated N/OFQ induced c-Fos expression in the hippocampus.

Anti-cyclic citrullinated peptide: diagnostic and prognostic values in juvenile idiopathic arthritis and rheumatoid arthritis in a Chinese population

OBJECTIVE

The incidence and clinical significance of anti-cyclic citrullinated peptide (CCP) antibodies in a cohort of Chinese patients with juvenile idiopathic arthritis (JIA) and adults with rheumatoid arthritis (RA) were studied.

METHODS

Anti-CCP antibodies were determined by enzyme-linked immunosorbent assay (ELISA) in 59 patients with JIA, 129 adult RA patients, 48 children with diseases other than JIA, 68 adult patients with rheumatic diseases other than RA, and 60 normal adults. Associations between anti-CCP antibodies and clinical and laboratory parameters were determined by Fisher's exact test.

RESULTS

Six of 59 (10.2%) patients with JIA and 71 of 129 (55%) patients with RA were positive for anti-CCP. Four of five RF-positive JIA patients and two of 54 RF-negative JIA patients were positive (p<0.001). One paediatric patient with allergy (0.9%) and two adult patients with rheumatic diseases other than RA (2.3%) were positive. All healthy controls were negative for anti-CCP. The specificity was 99.1% for JIA and 98.4% for RA. The sensitivity was 10.2% for JIA and 55% for RA. Positive predictive values were 85.7% for JIA and 97.3% for RA and negative predictive values were 66.9% for JIA and 68.5% for RA.

CONCLUSION

The anti-CCP antibody assay is a valuable tool for the diagnosis of RA and a subset of JIA in Chinese patients. It could be a useful predictive test for joint erosion in JIA of the polyarticular RF-positive subset and may be influential in the choice of the best therapeutic strategy in patients with recent-onset arthritis.

The teaching of anaesthesia in Singapore

This article describes the development of undergraduate and postgraduate anaesthesia teaching and training in Singapore. Anaesthesia teaching has evolved from art and apprenticeship to become systematic, scientific and evidence-based, while retaining an emphasis on hands-on practical training. Simulator training provides unique advantages, which the University Department of Anaesthesia has utilised in integrated medical student teaching.

Use of midazolam and ketamine as sedation for children undergoing minor operative procedures

OBJECTIVES

We used intravenous midazolam and ketamine for children undergoing minor operative procedures with satisfactory results. We aimed to further evaluate its efficacy and adverse effects in pediatric ward setting.

METHODS

This was a prospective study of all children undergoing minor operations with sedation in our pediatric general and oncology wards from July 1998 to June 1999. The procedures included lumber puncture+/-intrathecal chemotherapy, bone marrow aspiration+/-trephine biopsy, central venous catheter removal, skin biopsy, or their combination. All sedation procedures were started with midazolam 0.1 mg/kg and ketamine 1 mg/kg; they were increased gradually to 0.4 and 4 mg/kg, respectively, if necessary. Heart rate and SaO2 were continuously monitored.

RESULTS

Altogether, 369 minor operations were performed in 112 patients (male:female=2:1, median age 6 years, range 5 months-17 years). All achieved adequate sedation, with 96% within 30 s and 75% required just the starting dose. Younger children required a higher dosage (p=0.003 for midazolam, p<0.001 for ketamine). The median recovery time was 87 min, with no association with age, sex, or dosage of sedation, but was longer in patients having hallucination (p=0.001). Adverse effects included tachycardia (27.9%), increased secretion (17.6%), agitation (13.6%), nausea and vomiting (9.2%), hallucination (8.7%), desaturation (8.4%), and cataleptic reaction (0.8%). All desaturation episodes were transient and responded to oxygen supplement alone. None developed bronchospasm or convulsion. Some adverse effects were dose-related. Half of the children who received 0.3 mg/kg midazolam developed desaturation.

CONCLUSIONS

Intravenous midazolam-ketamine can provide rapid, effective, and safe sedation for children undergoing minor operations in ward setting. Adverse effects are mild. Midazolam above 0.3 mg/kg should be used with caution.

Primary immunodeficiency in Hong Kong and the use of genetic analysis for diagnosis

OBJECTIVES

To review the management of primary immunodeficiency and discuss recent advances in genetic analysis.

DESIGN

Retrospective study.

SETTING

University teaching hospital, Hong Kong.

PATIENTS

Children diagnosed with primary immunodeficiency and followed up in the immunology clinic during the period 1988 to 2003.

MAIN OUTCOME MEASURES

Demographic data, co-morbidities and treatment of patients, outcome and complications; identification of disease by genetic mutations.

RESULTS

Medical records of a total of 117 patients (72 male, 45 female) diagnosed with primary immunodeficiency in the Department of Paediatrics and Adolescent Medicine, Queen Mary Hospital, Hong Kong during the past 15 years (1988-2003) were reviewed. All patients were followed up in the immunology clinic. Some patients had been referred from the private sector or other hospitals for immunological workup. Six categories of primary immunodeficiency were identified: predominantly humoral defect (n=50), predominantly cellular defect (n=22), combined humoral and cellular defect (n=5), phagocytic defect (n=18), complement disorders (n=4), and others (n=18). Although infection was the underlying cause of most co-morbidities and mortality, autoimmune (n=7) and allergic (n=23) manifestations were common. In addition, three patients developed lymphoma. Recent advances in the genetic diagnosis of several types of primary immunodeficiency were also reviewed: X-linked Wiskott-Aldrich syndrome, X-linked chronic granulomatous disease, X-linked agammaglobulinaemia, X-linked lymphoproliferative syndrome, leukocyte adhesion disease type I, and X-linked hyperimmunoglobulin M syndrome. This provides an invaluable means of understanding the molecular basis of primary immunodeficiency and has important clinical applications.

CONCLUSIONS

Co-morbidities like autoimmune disease and allergic disease are common in patients with primary immunodeficiency and should be carefully evaluated. Likewise, a diagnosis of primary immunodeficiency should be considered when evaluating patients with these conditions. Rapid progress in the field of molecular genetics will enable definite and early diagnosis, and more importantly, potential curative therapy to be administered.

Effects of isoflurane and propofol on cortical somatosensory evoked potentials during comparable depth of anaesthesia as guided by bispectral index

BACKGROUND

The aim of this study was to determine if propofol caused less suppression of cortical somatosensory evoked potentials (SSEPs) during spine surgery compared with isoflurane during comparable depth of anaesthesia as guided by bispectral index (BIS) measurements.

METHODS

This was a randomized controlled trial of propofol and isoflurane involving 60 patients undergoing elective spine surgery. BIS monitoring was used to guide a consistent and comparable depth of anaesthesia, the index was maintained at between 40 and 50 during anaesthesia. The cortical SSEP P40-N50 peak-to-peak amplitude and latency time to the P40 peak were measured before induction of anaesthesia, after induction of anaesthesia, at the start of skin incision, at the start of pedicle screw insertion and at the start of rod insertion, by a neurophysiologist blinded to drug allocation.

RESULTS

Both propofol and isoflurane decreased SSEP amplitude and increased latency during the course of anaesthesia. After achieving a comparable depth of anaesthesia, the SSEP amplitude was significantly lower with isoflurane, 1.5 (1.0) vs 2.4 (1.4) muV (P=0.005). Latency was significantly longer with isoflurane, 39.5 (3.9) vs 37.3 (3.1) ms (P=0.024). Isoflurane was associated with greater variability of SSEP amplitude during the course of anaesthesia and surgery, coefficient of variation 35.4 (18.0) vs 21.2 (10.2)% (P=0.008).

CONCLUSIONS

Propofol anaesthesia caused less suppression of the cortical SSEP, with better preservation of SSEP amplitude, and less variability at an equivalent depth of anaesthesia.

Antirecipient helper and cytotoxic T-cell frequencies in bone marrow transplantation

We assayed helper T-lymphocyte precursor frequencies (HTLPf), interferon (IFN)-gamma-producing cell frequencies (IFN-gammaPf) and CTL precursor frequencies (CTLPf) to see if they could predict the severity of acute graft-versus-host disease (aGVHD) and disease relapse after transplantation. In all, 48 bone marrow transplantation (BMT) patients and their HLA-identical sibling (n=29) or matched unrelated donors (MUD) (n=19) were recruited. HTLPf, IFN-gammaPf and CTLPf were measured using a limiting dilution assay (LDA). Patients were followed prospectively to assess the severity of aGVHD and the status of the primary disease after BMT. High (>5 x 10(-6)) HTLPf, CTLPf and IFN-gammaPf were significantly associated with the occurrence and severity of aGVHD in patients who received transplants from HLA-identical sibling. Among patients receiving BMT from MUD, HTLPf and CTLPf, but not IFN-gammaPf, were associated with aGVHD. Five patients had disease relapse post-BMT and the risk was not significantly associated with HTLPf, CTLPf or IFN-gammaPf. Patients with high (>5 x 10(-6)) HTLPf, IFN-gammaPf or CTLPf before BMT are at higher risk of developing aGVHD after transplantation from both matched sibling donors and MUD. Whether these parameters can predict disease relapse would have to be investigated with a larger cohort of patients.

Klebsiella infection in patients with thalassemia

Klebsiella infection has previously been reported in a few patients with transfusion-dependent thalassemia. The incidence and clinical spectrum of this infection in our cohort of patients were reviewed retrospectively. Among 160 patients observed for 12 years, there were 15 episodes of Klebsiella infection that occurred in 12 patients (7.5%), resulting in an incidence of 0.78 infections per 100 patient-years. The clinical spectrum included sinusitis (4 cases), intracranial infection (5 cases), septicemia (4 cases), and abscesses of the liver, lung, kidney, and parotid gland (1 case each). Three patients had recurrent infections involving different sites, 2 (16%) died of fulminant septicemia, and 3 (25%) had significant permanent neurological deficits. The antibiotic susceptibility pattern for the isolates was similar to the pattern for isolates recovered in the community. With regard to predisposing factors, iron overload and liver function derangement were found to be significant on univariate analysis (P=.046 and P=.049, respectively) but insignificant on multivariate analysis. Klebsiella infection was a serious and frequently encountered complication in our patients with transfusion-dependent thalassemia, resulting in high mortality and morbidity rates.

Teaching first-year medical students physiology: does the human patient simulator allow for more effective teaching?

BACKGROUND

Although the Human Patient Simulator (HPS) is an effective teaching tool in many medical fields, literature supporting its use in the teaching of physiology to medical students is lacking. This study investigated the effectiveness of HPS-based teaching of cardiovascular physiology to first-year medical students.

METHODS

Two hundred and ten first-year medical students were scheduled to our HPS laboratory with the purpose of demonstrating "physiology in action". Students were divided into groups of 19-25 each, and attended a lecture followed by a HPS session. Using a theatre-type simulator complete with mannequin, anaesthesia machine and monitors (METI, Sarasota FL), the scenarios of hypovolaemia, sepsis, and cardiac failure were run to demonstrate the physiological changes that occur with changes in preload, afterload, and cardiac contractility. Each student was given a true/false test before, and again after the HPS session, followed by a survey of their learning experience.

RESULTS

There was marked improvement in test scores after the HPS session (82.1% vs. 64.6%, P < 0.001). Most of the students felt that HPS was a better teaching tool (94.5%) and raised more questions (76.5%) than lectures. They wanted more topics to be taught this way (96%), as they could apply and re-enforce textbook knowledge, and visualise real-time changes. However, they felt that their experience could have been enhanced with more time and smaller groups.

DISCUSSION

HPS is an excellent teaching tool as it stimulates student curiosity and makes knowledge acquisition and understanding easier. It is highly desirable to be incorporated into the teaching of physiology.

Alterations of frizzled (FzE3) and secreted frizzled related protein (hsFRP) expression in gastric cancer

Wnt signaling pathway is important for development and carcinogenesis. Alterations of this pathway, such as mutations in adenomatous polyposis coli (APC) gene and activation mutations of beta-catenin, would result in stabilization of beta-catenin and subsequent translocation to nucleus where genes are transcribed. Recently, a receptor of Wnt, FzE3 was found to be up-regulated in esophageal carcinoma while a non-receptor antagonist of Wnt, secreted frizzled related protein (hsFRP) was found to be down-regulated in some cancer. These findings suggested that FzE3 is a potential oncogene while hsFRP is a potential tumor suppressor gene. We aimed to investigate whether FzE3 and hsFRP were altered in gastric cancer. Twelve cases of gastric cancer, including 7 cases of intestinal type, 4 cases of diffuse type and I case of mixed type, were studied. FzE3 and hsFRP mRNAs were expressed in most of the paired normal gastric tissues. FzE3 was over-expressed in 9 cases (75%) of gastric carcinoma tissues while hsFRP was down-regulated in 2 cases (16%). Beta-catenin nuclear staining was identified in 3 cases (27%) and cyclin D1 was expressed in 5 cases (41%) of cancer samples. All these cases were associated with either up-regulation of FzE3 or down-regulation of hsFRP. Our results suggested that alterations of FzE3 or hsFRP were frequent in gastric cancer. These provide alternative mechanisms leading to activation of Wnt signaling pathway in gastric carcinogenesis.

IRF-1-mediated CAS expression enhances interferon-gamma-induced apoptosis of HT-29 colon adenocarcinoma cells

The expression of CAS is reported to be upregulated in a variety of human tumor cells, and such expression correlates with the development of tumors. CAS also plays a role in apoptosis. We investigated whether CAS expression affects the susceptibility of tumor cells to IFN-gamma-induced apoptosis. Our data show that IFN-gamma treatment induces CAS expression in HT-29 tumor cells. IFN-gamma-induced gene expression is primarily mediated by the transcriptional factor, IRF-1. Our data show that IRF-1 mediates IFN-gamma-induced CAS expression. Transfection of HT-29 cells with CAS expression vector did not induce apoptosis of cells; nevertheless, CAS overexpression greatly enhanced IFN-gamma-induced apoptosis of cells. CPP32 is regarded as one of the central apoptosis executioner molecules. CAS overexpression enhances IFN-gamma-induced CPP32 expression. These results indicate that tumor cells highly expressing CAS may be more susceptible to apoptosis induced by reagents that are capable of inducing CAS expression. Thus, CAS may be a target for the elimination of tumors.

Adenomatous polyposis coli gene mutation and decreased wild-type p53 protein expression in oral submucous fibrosis: a preliminary investigation

OBJECTIVE

The purpose of this study was to identify the adenomatous polyposis coli (APC) tumor suppressor gene mutation and level of wild-type p53 protein expression in patients with oral submucous fibrosis (OSF).

STUDY DESIGN

Cells from OSF and control subjects were cultured in Dulbecco modified Eagle medium with 10% fetal bovine serum at 37 degrees C. Genomic DNA was extracted from cultured cells and used as a template for polymerase chain reaction amplification of the APC tumor suppressor gene. The presence of wild-type p53 protein in cell lysates of cultured cells was analyzed by Western blot. Data were analyzed by the sign test for nonparametric samples and by analysis of variance.

RESULTS

The results showed that the APC gene of explant cultured cells from OSF patients (8/8) had a CGA-to-GGA transition mutation at codon 498 that resulted in an Arg-to-Gly missense mutation (P <.01). All (8/8) normal HGF cultures revealed expression of the wild-type APC protein. Cells cultured from 7 of 8 OSF patients were also found to have a single nucleotide deletion at nucleotide 1494 that resulted in creating a stop codon (TGA) at codon 504 (P <.01). This created a premature signal for the endpoint of translation and thus resulted in the generation of a truncated protein product that encodes a polypeptide of 503 amino acid residue. It was found that wild- type p53 protein in human gingival fibroblast cell cultures was significantly higher than in OSF cells (P <.01).

CONCLUSION

Alterations of the APC and wild-type p53 tumor suppressor genes in OSF may imply a risk for progression to oral cancer.

Inverse association between cyclooxygenase-2 overexpression and microsatellite instability in gastric cancer

This study examined the association between cyclooxygenase-2 (COX-2) overexpression and microsatellite instability (MSI) in gastric cancer. COX-2 expression was assessed by immunohistochemistry and scored in a semi-quantitative manner whereas MSI status was characterized by nine microsatellite markers. The clinicopathological features of cancers including survival data were analyzed. Of the 109 gastric cancers studied, COX-2 overexpression and high level of MSI (MSI-H) was detected in 64.2 and 22.0% cases respectively. Gastric tumors with MSI-H phenotypes had significantly lower level of COX-2 expression levels when compared to MSI-L and MSS tumors (P=0.002). Moreover, COX-2 overexpression was associated with tumor invasion beyond submucosa (P=0.045) and there was a trend favoring better survival in gastric cancers without COX-2 overexpression (P=0.07). The results from this study suggest that gastric cancer with microsatellite instability or COX-2 overexpression present with diverse clinicopathological features.

Concurrent hypermethylation of multiple tumor-related genes in gastric carcinoma and adjacent normal tissues

BACKGROUND

Transcriptional silencing by CpG-island hypermethylation now is believed to be an important mechanism of tumorigenesis. To date, studies on CpG-island hypermethylation in gastric carcinoma and adjacent normal tissues are few.

METHODS

The authors examined 5 gastric carcinoma cell lines, 26 frozen gastric carcinoma tissues and their adjacent nontumor area for concurrent CpG-island hypermethylation in 6 tumor-related genes (p15, p16, E-cadherin, GST-pi, hMLH1, and VHL) by methylation-specific polymerase chain reaction. Nontumorous gastric tissues from 10 gastritis patients were used as controls.

RESULTS

Hypermethylation was not detected in any tissue taken from gastritis patients but was identified in all 5 cell lines and in 24 (92.3%) gastric carcinoma patients. CpG-island methylation in tumor-related genes also was detected in 7 out of the 25 adjacent normal tissues from cancer patients. Hypermethylation of E-cadherin, p15, and p16 were detected more frequently than GST-pi and hMLH1, whereas aberrant methylation of VHL was not detected. Concurrent hypermethylation in 2 or more tumor-related genes was detected in 3 out of the 5 gastric carcinoma cell lines, 22 (84.6%) tumor samples, and 5 (20%) adjacent gastric tissues. Eighteen (69.2%) tumor samples showed hypermethylation in >or= 3 genes.

CONCLUSIONS

The current study showed that concurrent hypermethylation of multiple tumor-related genes is detected frequently in gastric carcinoma and adjacent normal tissues. Study findings suggested that a mechanism that leads to dysregulation in CpG-island methylation is likely to be involved in the early gastric carcinogenesis process.

Concurrent hypermethylation of multiple tumor-related genes in gastric carcinoma and adjacent normal tissues

BACKGROUND

Transcriptional silencing by CpG-island hypermethylation now is believed to be an important mechanism of tumorigenesis. To date, studies on CpG-island hypermethylation in gastric carcinoma and adjacent normal tissues are few.

METHODS

The authors examined 5 gastric carcinoma cell lines, 26 frozen gastric carcinoma tissues and their adjacent nontumor area for concurrent CpG-island hypermethylation in 6 tumor-related genes (p15, p16, E-cadherin, GST-pi, hMLH1, and VHL) by methylation-specific polymerase chain reaction. Nontumorous gastric tissues from 10 gastritis patients were used as controls.

RESULTS

Hypermethylation was not detected in any tissue taken from gastritis patients but was identified in all 5 cell lines and in 24 (92.3%) gastric carcinoma patients. CpG-island methylation in tumor-related genes also was detected in 7 out of the 25 adjacent normal tissues from cancer patients. Hypermethylation of E-cadherin, p15, and p16 were detected more frequently than GST-pi and hMLH1, whereas aberrant methylation of VHL was not detected. Concurrent hypermethylation in 2 or more tumor-related genes was detected in 3 out of the 5 gastric carcinoma cell lines, 22 (84.6%) tumor samples, and 5 (20%) adjacent gastric tissues. Eighteen (69.2%) tumor samples showed hypermethylation in >or= 3 genes.

CONCLUSIONS

The current study showed that concurrent hypermethylation of multiple tumor-related genes is detected frequently in gastric carcinoma and adjacent normal tissues. Study findings suggested that a mechanism that leads to dysregulation in CpG-island methylation is likely to be involved in the early gastric carcinogenesis process.

Concurrent hypermethylation of multiple tumor-related genes in gastric carcinoma and adjacent normal tissues

BACKGROUND

Transcriptional silencing by CpG-island hypermethylation now is believed to be an important mechanism of tumorigenesis. To date, studies on CpG-island hypermethylation in gastric carcinoma and adjacent normal tissues are few.

METHODS

The authors examined 5 gastric carcinoma cell lines, 26 frozen gastric carcinoma tissues and their adjacent nontumor area for concurrent CpG-island hypermethylation in 6 tumor-related genes (p15, p16, E-cadherin, GST-pi, hMLH1, and VHL) by methylation-specific polymerase chain reaction. Nontumorous gastric tissues from 10 gastritis patients were used as controls.

RESULTS

Hypermethylation was not detected in any tissue taken from gastritis patients but was identified in all 5 cell lines and in 24 (92.3%) gastric carcinoma patients. CpG-island methylation in tumor-related genes also was detected in 7 out of the 25 adjacent normal tissues from cancer patients. Hypermethylation of E-cadherin, p15, and p16 were detected more frequently than GST-pi and hMLH1, whereas aberrant methylation of VHL was not detected. Concurrent hypermethylation in 2 or more tumor-related genes was detected in 3 out of the 5 gastric carcinoma cell lines, 22 (84.6%) tumor samples, and 5 (20%) adjacent gastric tissues. Eighteen (69.2%) tumor samples showed hypermethylation in >or= 3 genes.

CONCLUSIONS

The current study showed that concurrent hypermethylation of multiple tumor-related genes is detected frequently in gastric carcinoma and adjacent normal tissues. Study findings suggested that a mechanism that leads to dysregulation in CpG-island methylation is likely to be involved in the early gastric carcinogenesis process.

Two novel quantitative trait loci on mouse chromosomes 6 and 4 independently and synergistically regulate plasma apoB levels

An elevated plasma apolipoprotein B (apoB) level is a strong predictor of atherosclerosis and coronary heart disease. Epidemiologic and family linkage studies have suggested a genetic basis for the wide variations of plasma apoB levels in the general population. Using a human apoB transgenic (HuBTg) mouse model, we have previously shown that hepatic apoB-100 secretion is a major determinant of the high and low plasma human apoB levels in HuBTg mice of the C57BL/6 (B6) and 129/Sv (129) strains, respectively. In the present article, we present the identification of two novel quantitative trait loci (QTL) as major regulators of plasma human apoB levels in the F(2) and N(2) (backcrossed) offspring (n = 572) derived from crosses between the B6 and 129 mouse strains. These loci were designated ApoB regulator genes (Abrg), because the gene products are likely to be involved in the regulation of plasma apoB levels either directly or indirectly. The first locus, designated Abrg1, was mapped to chromosome 6 in 8-week-old male and female mice with a combined logarithm of odds ratio (LOD) score of 14 at the D6Mit55 marker ( approximately 45.9 cM). Abrg1 contributed approximately 35% of the genetic variance. The second locus, designated Abrg2, was mapped to chromosome 4 with an LOD score of 8.6 in 8-week-old male mice but an LOD score of only 2.0 in 8-week-old female mice at the D4Mit27 marker ( approximately 35 cM). Abrg2 contributed approximately 26% of the genetic variance. Epistasis between Abrg1 and Abrg2 was detected and accounted for approximately 12% of the genetic variance. The combination of these two QTL has major effects (>70%) on the regulation of plasma human apoB levels in the tested population. In summary, we have identified two novel loci that have a major role in the regulation of plasma apoB levels and are likely to regulate the secretory pathway of apoB. The human orthologs for the Abrg loci are strong candidates for human disorders characterized by altered plasma apoB levels, such as FCHL and familial hypobetalipoproteinemia.

Somatic beta-catenin mutation in gastric carcinoma--an infrequent event that is not specific for microsatellite instability

We screened 90 cases of gastric carcinoma (GCA) samples for beta-catenin exon 3 mutation and assessed its possible relationship with microsatellite instability (MSI). Three mutations were detected in two samples, including a single mutation in an intestinal type and double mutations in a diffuse type GCA. One of the mutations found in the diffuse type GCA sample was a non-sense mutation at codon 68 (CAG-->TAG). This novel mutation was predicted to disrupt the binding of beta-catenin to alpha-catenin and may be related to the diffuse type morphology. The other two mutations were missense mutations involved or related to the GSK-3beta phosphorylation site, which have been reported previously. No MSI can be demonstrated in the two cases with beta-catenin mutation. Our results suggested that beta-catenin mutation was infrequent in GCA and appeared not specific for MSI.

Expression and cellular localization of COX-1 and -2 in Helicobacter pylori gastritis

BACKGROUND

There are conflicting reports on the expression of cyclooxygenase in Helicobacter pylori infection.

AIM

To evaluate the expression of COX-1 and COX-2 in H. pylori gastritis at messenger RNA (mRNA) and protein levels.

METHODS

Endoscopic gastric biopsies were obtained from patients with non-ulcer dyspepsia. The levels of COX-1 and COX-2 mRNA were compared between H. pylori-infected and uninfected specimens using reverse transcription-polymerase chain reaction. The immunohistochemical findings were correlated with the cellular localization of cyclooxygenase mRNA using in situ hybridization.

RESULTS

A total of 40 H. pylori-infected and 40 uninfected specimens were studied. mRNA of COX-2 but not COX-1 was elevated in H. pylori-infected mucosa. COX-1 was localized to the mononuclear inflammatory, endothelial and smooth muscle cells in the lamina propria. COX-2 was barely detectable in uninfected mucosa but was strongly expressed in the foveolar and glandular epithelia in H. pylori gastritis.

CONCLUSION

Cyclooxygenase-1 is expressed in the mononuclear inflammatory, endothelial and smooth muscle cells in the lamina propria irrespective of the H. pylori status. By contrast, H. pylori induces COX-2 expression in the foveolar and glandular epithelia.

Association between cyclo-oxygenase-2 overexpression and missense p53 mutations in gastric cancer

Wild-type p53 competitively binds to the promoter region of COX-2 in vitro and inhibits its transcription. We examined the association between p53 mutation and COX-2 expression in gastric cancer. COX-2 over-expression was seen in 19 (48.7%) cases. These tumours had more lymph-node metastasis (P = 0.048) and tended to have a poorer survival (P = 0.07). Missense mutations of p53 were detected in 20 (51.3%) patients and had a significantly stronger COX-2 expression than tumours without p53 mutation (P = 0.016). Our results suggest a link between p53 mutation and COX-2 overexpression in gastric cancer.

Up-regulation of cyclooxygenase-1 and -2 in human gastric ulcer

BACKGROUND

The expression of cyclooxygenase (COX) in human gastric ulcers is unknown.

AIM

To study the expression and cellular localization of cyclooxygenase in human gastric ulcers.

METHODS

A total of 38 surgical gastric ulcer specimens were studied; 20 were Helicobacter pylori-positive and 18 were associated with NSAID use. Twenty non-ulcerated, histologically normal gastric specimens were used as controls. The cellular localization of COX-1 and COX-2 were determined by immunohistochemistry and double immunofluorescence. Cyclooxygenase messenger RNA (mRNA) was measured by reverse transcription-polymerase chain reaction and localized by in situ hybridization.

RESULTS

In control specimens, COX-1 was detected in stromal cells in the lamina propria. There was focal and weak immunostaining for COX-2 in the foveolar epithelium. At the ulcer edge, COX-1 was significantly increased in lamina propria cells whereas COX-2 was strongly expressed in the hyperplastic foveolar epithelium in H. pylori- and non-steroidal anti-inflammatory drugs (NSAID)-associated ulcers. At the ulcer base, there was strong expression of COX-1 and COX-2 in myofibroblasts, macrophages and endothelial cells in the granulation tissue, irrespective of H. pylori status or NSAID use. Messenger RNA of COX-1 and COX-2 were demonstrated by reverse transcription-polymerase chain reaction. Double immunofluorescence and in situ hybridization confirmed the cellular localization of cyclooxygenase at protein and mRNA levels, respectively.

CONCLUSION

Both COX-1 and COX-2 are up-regulated in human gastric ulcers.

Detection of microchimerism by PCR is a function of amplification strategy

BACKGROUND

Suitable detection methods are needed to support larger studies of microchimerism and the allogeneic exposures that may be etiologically related to it.

STUDY DESIGN AND METHODS

A twotier PCR strategy for microchimerism detection was developed on the basis of the observation that assay sensitivity for the detection of microchimerism depends on the specificity with which primer pairs recognize sequences unique to the minor population. First, specimens are tested to determine the host HLA class II genotype by using a locus-specific PCR strategy with low sensitivity for microchimerism. Then, a sequence-specific PCR analysis having high sensitivity for detection of microchimerism is applied to detect and quantitate the minor population. Locus-specific, group-specific, and sequence-specific amplification strategies for the detection of distinct minor WBC populations prepared ex vivo were compared. In addition, 39 clinical samples from patients with known transfusion-associated microchimerism and 20 umbilical cord blood (CB) specimens containing maternal WBCs were studied.

RESULTS

Locus-specific amplification detected 17 (94%) of 18 cases in which microchimerism was present at 10 percent, but only 1 of 51 cases with microchimerism < or = 1 percent. Group-specific amplification detected all 63 cases with minor populations present at > or = 0.10 percent, but only 16 of 21 cases at the 0.01 percent level. Sequence-specific amplification detected 100 percent of cases down to the 0.01 percent level. When applied to clinical samples, locus-specific amplification reliably identified the major population but proved insensitive to low-level minor populations.

CONCLUSIONS

For the detection of microchimerism, assay sensitivity is a function of amplification strategy. These results suggest a simple approach to population screening for microchimerism: the background population of WBCs is typed by a locus-specific method, while minor population(s) can then be sought by using one or several sequence-specific amplifications.

Use of sedation in dentistry

Fear and avoidance of dental treatment are major deterrents to oral health. Sedation can be used to control both the patient's fear and anxiety so that proper dental care can be provided for these patients. The purpose of this article is to discuss the use of sedation in dentistry and to provide a recommendation on the requirements and medico-legal aspects of sedation for the practitioner interested in incorporating sedation into their practice.

Transcriptional repression by Drosophila methyl-CpG-binding proteins

C methylation at genomic CpG dinucleotides has been implicated in the regulation of a number of genetic activities during vertebrate cell differentiation and embryo development. The methylated CpG could induce chromatin condensation through the recruitment of histone deacetylase (HDAC)-containing complexes by methyl-CpG-binding proteins. These proteins consist of the methylated-DNA binding domain (MBD). Unexpectedly, however, several studies have identified MBD-containing proteins encoded by genes of Drosophila melanogaster, an invertebrate species supposed to be void of detectable m(5)CpG. We now report the genomic structure of a Drosophila gene, dMBD2/3, that codes for two MBD-containing, alternatively spliced, and developmentally regulated isoforms of proteins, dMBD2/3 and dMBD2/3Delta. Interestingly, in vitro binding experiments showed that as was the case for vertebrate MBD proteins, dMBD2/3Delta could preferentially recognize m(5)CpG-containing DNA through its MBD. Furthermore, dMBD2/3Delta as well as one of its orthologs in mouse, MBD2b, could function in human cells as a transcriptional corepressor or repressor. The activities of HDACs appeared to be dispensable for transcriptional repression by dMBD2/3Delta. Finally, dMBD2/3Delta also could repress transcription effectively in transfected Drosophila cells. The surprisingly similar structures and characteristics of the MBD proteins as well as DNA cytosine (C-5) methyltransferase-related proteins in Drosophila and vertebrates suggest interesting scenarios for their roles in eukaryotic cellular functions.

Molecular cloning, characterization, and expression of a cDNA coding Copper/Zinc superoxide dismutase from black porgy

A full-length complementary DNA (cDNA) clone encoding a putative copper/zinc superoxide dismutase (Cu/Zn-SOD) was amplified by a Polymerase Chain Reaction (PCR) based technique from cDNA synthesized from black porgy, Acanthopagrus schlegeli, mRNA. Nucleotide sequence analysis of this cDNA clone revealed that it comprised a complete open reading frame coding for 154 amino acid residues. The deduced amino acid sequence showed slightly higher identity (72.8-78.1%) with shark and swordfish Cu/Zn-SOD than with Cu/Zn-SOD from mammalian (68.1-70.7%) and plant (55.5-56.5%) sources. The residues required for coordinating copper and zinc are conserved as they are among all reported Cu/Zn-SOD sequences. The deduced amino acid sequence lacks mitochondria targeting sequence, which suggests that the black porgy cDNA clone encodes a cytosolic Cu/Zn-SOD. The coding region of Cu/Zn-SOD from black porgy was introduced into an expression vector, pET-20b(+), and transformed into Escherichia coli AD494(DE3)pLysS. A predominant achromatic zone was detected by activity staining of native PAGE. This indicates that the Cu/Zn-SOD cDNA clone can express active Cu/Zn-SOD enzyme in E. coli.

Interaction of Helicobacter pylori eradication and non-steroidal anti-inflammatory drugs on gastric epithelial apoptosis and proliferation: implications on ulcerogenesis

BACKGROUND

Apoptosis is associated with loss of gastric mucosal integrity and may play an important role in ulcer development.

AIM

To examine how Helicobacter pylori and NSAIDs interact to effect apoptosis and proliferation of the gastric mucosa.

METHODS

Patients presenting with musculoskeletal pain requiring NSAID treatment and without previous exposure to NSAID or pre-existing ulcers were recruited. Patients were divided into three groups: (A) H. pylori-infected; (B) H. pylori-eradicated; and (C) non-infected patients. They were given naproxen for 8 weeks. Patients with non-ulcer dyspepsia and H. pylori infection who were given anti-Helicobacter therapy were recruited as controls (D). Endoscopy was performed at baseline and 8-weeks after receiving naproxen. Gastric antral biopsies were obtained to assess apoptosis by terminal uridine deoxynucleotidyl nick end-labelling (TUNEL) and proliferation by Ki67 immunostaining.

RESULTS

A total of 55 patients were studied. H. pylori-positive patients had a higher apoptosis and proliferation index at baseline than non-infected patients (P < 0.0001), and eradication of H. pylori resulted in a significant reduction in these parameters. The NSAID induced apoptosis in non-infected subjects (P=0.03) whilst apoptosis was reduced in H. pylori-positive patients receiving NSAID (P=0.02). After 8 weeks of NSAID, post-treatment apoptosis was significantly higher in patients with persistent H. pylori infection than in non-infected patients (P=0.01).

CONCLUSIONS

Eradication of H. pylori prior to NSAID therapy significantly reduces the level of apoptosis in the gastric mucosa, which may contribute to maintaining mucosa integrity and preventing ulcer development.

One-codon alternative splicing of the CpG MTase Dnmt1 transcript in mouse somatic cells

The genomic methylation patterns in the mammalian somatic cells are presumably maintained by a single enzyme, dnmt1. In mouse, this DNA (cytosine-5)-methyltransferase, or CpG MTase, is encoded by the Dnmt1 gene. We now present evidence that in different tissues and cell types, the primary transcript of mouse dnmt1 is alternatively spliced to generate two poly-(A) RNAs of approximately similar abundance. This alternative splicing most likely originates from the existence of two tandemly arranged acceptor sites separated by only 3 nt. The two Dnmt1 mRNAs thus encode two CpG MTases differing by two amino acids. We discuss the implications of the discovery of two dnmt1 isozymes, instead of one enzyme as previously thought, in the somatic cells of both mouse and human.

An assessment of the effects on coagulation of midtrimester and final-trimester amniotic fluid on whole blood by Thrombelastograph analysis

The Thrombelastograph((R)) test (TEG; Haemoscope Corporation, Skokie, IL) was used to assess the effects of midtrimester and final-trimester amniotic fluid (AF) on whole blood coagulation. Different volumes of midtrimester and final-trimester AF were added to whole blood from nonpregnant volunteers in a series of TEG tests. The addition of both midtrimester and final-trimester AF resulted in significant decreases in reaction time (P < 0.001) and time from reaction to a fixed level of clot firmness (P < 0.05) and significant increases in angle (P < 0.05) and coagulation index (P < 0.05) values. This reflects accelerated clot initiation and propagation. There was no significant change in the maximal amplitude or % lysis at 30 and 60 min with the addition of either midtrimester or final-trimester AF. There was no significant difference between the effects of midtrimester and final-trimester AF on whole blood TEG. TEG may be an additional useful tool in the treatment of coagulopathy in AF embolism.

IMPLICATIONS

We used the Thrombelastograph((R)) test (Haemoscope Corporation, Skokie, IL) to assess the effects of midtrimester and final-trimester amniotic fluid (AF) on whole blood coagulation. Results demonstrate that AF accelerates clot initiation and propagation. The Thrombelastograph((R)) test may be useful in assessing coagulopathy in patients with AF embolism.

Acupuncture and chronic pain management

INTRODUCTION

Although acupuncture has been widely used to treat a variety of pain conditions, convincing scientific evidence for its efficacy is lacking. Earlier randomised controlled trials attempted to follow a double-blind, placebo-controlled model. This approach has encountered many problems such as the virtual impossibility of blinding the acupuncturist and the uncertainties inherent in choosing control acupuncture points. The objective of this review is to assess if acupuncture is an effective treatment for chronic pain. In addition, a number of key methodological issues that arise in the controlled evaluation of acupuncture will be discussed.

METHODS

This review is based on the result of previous reviews, meta-analyses and consensus conference. The search was performed with MEDLINE (from 1966), EMBASE (from 1980) and Cochrane library (1999, volume 1). Only randomised trials of acupuncture (involved needling) for subjects with chronic pain published in English were included.

RESULTS

Basic science research has demonstrated convincingly that at least in the context of acute pain, acupuncture's effects are related to the release of a variety of natural opioids. Acupuncture has been shown to be effective for postoperative dental pain. There are reasonable studies showing relief of pain with acupuncture on diverse pain conditions such as menstrual cramps, tennis elbow, low back pain and fibromyalgia. This suggests that acupuncture may have a more general effect on pain. However, there are also studies which provide equivocal results because of design, sample size and other factors. The issue is further complicated by inherent difficulties in the use of appropriate controls, such as placebo and sham acupuncture groups.

CONCLUSION

As most of the studies were of poor methodological quality, there is a need for further high quality randomised controlled trials. Future studies should also have larger sample sizes, use a valid acupuncture treatment, and have both a short-term and long-term follow-up.

Incidence of and breed-related risk factors for gastric dilatation-volvulus in dogs

OBJECTIVE

To compare incidence of and breed-related risk factors for gastric dilatation-volvulus (GDV) among 11 dog breeds (Akita, Bloodhound, Collie, Great Dane, Irish Setter, Irish Wolfhound, Newfoundland, Rottweiler, Saint Bernard, Standard Poodle, and Weimaraner).

DESIGN

Prospective cohort study.

ANIMALS

1,914 dogs.

PROCEDURE

Owners of dogs that did not have a history of GDV were recruited at dog shows, and the dog's length and height and depth and width of the thorax and abdomen were measured. Information concerning the dogs' medical history, genetic background, personality, and diet was obtained from owners, and owners were contacted by mail and telephone at approximately 1-year intervals to determine whether dogs had developed GDV or died. Incidence of GDV based on the number of dog-years at risk was calculated for each breed, and breed-related risk factors were identified.

RESULTS AND CLINICAL RELEVANCE

Incidence of GDV for the 7 large (23 to 45 kg [50 to 99 lb]) and 4 giant (> 45 kg [> 99 lb]) breeds was 23 and 26 cases/1,000 dog-years at risk, respectively. Of the 105 dogs that developed GDV, 30 (28.6%) died. Incidence of GDV increased with increasing age. Cumulative incidence of GDV was 5.7% for all breeds. The only breed-specific characteristic significantly associated with a decreased incidence of GDV was an owner-perceived personality trait of happiness.

The effect of propofol on human gastric and colonic muscle contractions

Although propofol is widely used for sedation in the intensive care unit, there are limited data on its effects on gastrointestinal motility. For that reason, we studied the in vitro effects of propofol on human gastric and colonic smooth muscle. Grossly normal human gastric and colonic muscle strips were mounted in an organ bath set-up for isometric contraction and stimulated by acetylcholine (Ach), using a cumulative dose schedule in the absence or presence of different concentrations of propofol [1.7 x 10(-6) M (0.3 microg/mL) to 4.4 x 10(-4) M (78 microg/mL)]. Ach led to concentration-dependent contraction of both gastric and colonic muscle strips, whereas propofol, at a concentration 6.7 x 10(-6) M (1.2 microg/mL) and above, significantly depressed Ach-induced contraction in a concentration-dependent manner for both smooth muscle preparations. In addition, propofol, at a concentration 2.7 x 10(-5)M (4.8 microg/mL) and above, depressed spontaneous contractile activity of both smooth muscle preparations. Fat emulsion 10% (Intralipid), the solvent for propofol, had no effect on either the spontaneous activity or the Ach-induced contraction of gastric and colonic smooth muscles.

IMPLICATIONS

The success of enteral feeding requires a normal gastrointestinal motility. We found that, at clinically relevant concentrations, propofol impaired gastrointestinal contractile activity. Further investigations are required to determine the clinical significance of this change.

The effect of propofol on human gastric and colonic muscle contractions

Although propofol is widely used for sedation in the intensive care unit, there are limited data on its effects on gastrointestinal motility. For that reason, we studied the in vitro effects of propofol on human gastric and colonic smooth muscle. Grossly normal human gastric and colonic muscle strips were mounted in an organ bath set-up for isometric contraction and stimulated by acetylcholine (Ach), using a cumulative dose schedule in the absence or presence of different concentrations of propofol [1.7 x 10(-6) M (0.3 microg/mL) to 4.4 x 10(-4) M (78 microg/mL)]. Ach led to concentration-dependent contraction of both gastric and colonic muscle strips, whereas propofol, at a concentration 6.7 x 10(-6) M (1.2 microg/mL) and above, significantly depressed Ach-induced contraction in a concentration-dependent manner for both smooth muscle preparations. In addition, propofol, at a concentration 2.7 x 10(-5)M (4.8 microg/mL) and above, depressed spontaneous contractile activity of both smooth muscle preparations. Fat emulsion 10% (Intralipid), the solvent for propofol, had no effect on either the spontaneous activity or the Ach-induced contraction of gastric and colonic smooth muscles.

IMPLICATIONS

The success of enteral feeding requires a normal gastrointestinal motility. We found that, at clinically relevant concentrations, propofol impaired gastrointestinal contractile activity. Further investigations are required to determine the clinical significance of this change.

Two major forms of DNA (cytosine-5) methyltransferase in human somatic tissues

Thus far, only one major form of vertebrate DNA (cytosine-5) methyltransferase (CpG MTase, EC 2.1.1.37) has been identified, cloned, and extensively studied. This enzyme, dnmt1, has been hypothesized to be responsible for most of the maintenance as well as the de novo methylation activities occurring in the somatic cells of vertebrates. We now report the discovery of another abundant species of CpG MTase in various types of human cell lines and somatic tissues. Interestingly, the mRNA encoding this CpG MTase results from alternative splicing of the primary transcript from the Dnmt1 gene, which incorporates in-frame an additional 48 nt between exons 4 and 5. Furthermore, this 48-nt exon sequence is derived from the first, or the most upstream, copy of a set of seven different Alu repeats located in intron 4. The ratios of expression of this mRNA to the expression of the previously known, shorter Dnmt1 mRNA species, as estimated by semiquantitative reverse transcription-PCR analysis, range from two-thirds to three-sevenths. This alternative splicing scheme of the Dnmt1 transcript seems to be conserved in the higher primates. We suggest that the originally described and the recently discovered forms of CpG MTase be named dnmt1-a and dnmt1-b, respectively. The evolutionary and biological implications of this finding are discussed in relation to the cellular functions of the CpG residues and the CpG MTases.

Influence of temperature, pH and naloxone on the antinociceptive activity of Channa striatus (haruan) extracts in mice

We have previously shown that extracts from the snakehead fish, Channa striatus (haruan), have antinociceptive activity on their own, and enhance morphine antinociception. In furtherance of that study, we investigated the effects of temperature, pH and naloxone on the antinociceptive effects of haruan extracts in the mouse abdominal constriction test. The effects of temperature were only studied on mucus extracts since the fillet extract is prepared at high temperature under pressure. There was a general loss of inhibitory activity from 88.4% at 0 degrees C to 61.1% at 80-100 degrees C, though this was only significant at 80 degrees C. The effects of pH were studied on both extracts. Lowering the mucus extract pH to 6.0 (unadjusted pH 7.4) did not significantly affect its activity, while raising it to 8.0 attenuated its activity. Similarly, pH changes had no effect on the fillet extract except at pH 8.0 which produced apparently lower antinociception. Pretreatment with naloxone (4 mg/kg) had no significant effect on the inhibitory effects of either extract in the abdominal constriction test. These results suggest that the active ingredient(s) of these extracts is (are) relatively stable over a wide range of temperature and between pH 6.0 and 8.0. That would be consistent with the possibility of a glycoprotein, polypeptide or polysaccharide.