P–557 Trophectoderm biopsy technique and rate of mosaicism in human blastocysts

Study question

Do different trophectoderm biopsy techniques affect mosaicism rate in human blastocysts?

Summary answer

No statistical significance was found between biopsy techniques and mosaicism rate. However, an increase in mosaicism rate was observed when the flicking technique was used.

What is known already

Mosaicism is defined as two or more distinct cell lines within an embryo. Recent advances in Next Generation Sequencing (NGS) technology with an increased sensitivity allows a higher accuracy in quantification of mosaic levels in biopsied cells. The incidence of mosaicism is widely debated as there are many attributing technical and biological factors. Since, trophectoderm biopsy is a technically challenging process, it is crucial to ensure that the both biopsied cells and blastocyst suffers minimal damage during biopsy.

Study design, size, duration

This is a prospective study involving 222 patients (age range= 18–44, mean age= 31.5) who underwent IVF cycles in Alpha IVF, Malaysia from March 2019 to August 2019. Six hundred and sixty-eight (668) of the blastocysts were biopsied on Day 5 (Group 1) while 177 blastocysts were biopsied on Day 6 (Group 2). The blastocysts in these groups were further categorised into their corresponding biopsy techniques: (A) laser+pulling; (B) laser+flicking; (C) flicking only.

Participants/materials, setting, methods

Blastocysts which were at least fair graded (Gardner, 1999) were biopsied and vitrified (Cryotec, Japan). The number of biopsied cells ranged from 5 to 10 cells. All biopsied trophectoderm samples were subjected to Preimplantation Genetic Testing for Aneuploidy (PGT-A) with Next Generation Sequencing (NGS) (Ion Torrent, USA). Chromosomal mosaicism analysis was done using ReproSeq Mosaic PGS w1.1 workflow. Trophectoderm biopsied sample which were tested to have 20% to 80% aneuploid cells were reported as mosaic.

Main results and the role of chance

In Group 1, the mosaicism rates for biopsy technique A, B and C were 23.3% (104/446), 28.2% (58/206) and 37.5% (6/16) respectively. In Group 2, the mosaicism rates for biopsy technique A, B and C were 14.6% (7/48), 19.5% (23/118) and 27.3% (3/11) respectively. There were no significant differences (p > 0.05) in mosaicism rates between all study groups and subgroups.

Limitations, reasons for caution

Although no statistical significance was found between trophectoderm biopsy techniques and the prevalence of mosaicism, there is a trend of an increase in mosaicism rate when the flicking technique was used. Therefore, further studies with a larger sample size should be undertaken.

Wider implications of the findings: Our study demonstrates a trend in the decrease of mosaicism rate when laser pulses was used to loosen the cell junction of targeted cells. Hence, in place of the flicking method alone, laser pulses should be applied during trophectoderm biopsy if our findings are confirmed in a larger controlled study.

Trial registration number

Not applicable

P–148 Effect of additional laser assisted drilling (LAD) during trophectoderm (TE) biopsy on mosaicism rate

Study question

Does applying additional LAD during TE biopsy cause higher mosaicism rate in blastocysts?

Summary answer

Applying LAD during TE biopsy to create additional zona opening will produce more mosaic blastocysts.

What is known already

In Alpha IVF, laser assisted hatching (LAH) was done on day3 after ICSI for all pre-implantation genetic testing for aneuploidy (PGT-A) cycles. TE biopsy techniques used were laser+pulling (L+P), laser+flicking (L+F) and flicking only (F). At the time of biopsy, an extra step of creating additinonal artificial opening by LAD may be required when (a) blastocyst has very little herniated cells; (b) inner cell mass (ICM) is at the hatching point or biopsy site. Our internal study showed that biopsy using different techniques (L+P, L+F and F) does not affect mosaicism rate.

Study design, size, duration

This prospective study was designed to evaluate the effect of additional LAD during TE biopsy on the mosaicism rate. This study was conducted between 11th March–19th August 2019. Four hundred forty-three (443) patients had undergone oocyte retrieval and blastocyst culture after intracytoplasmic injection (ICSI) was done. A total of 824 hatching blastocyst (BG5) and fully hatched blastocyst (BG6) with at least a Grade A or Grade B TE (Gardner’s grading) were included in this study.

Participants/materials, setting, methods

LAH was done on day3 post-ICSI while biopsy was done on day5 and/or day6 for PGT-A. Laser pulse length used during LAH and biopsy was fixed at 400ms. The biopsied blastocysts were classified into 3 groups: (A) BG6 (n = 79), (B) BG5 without additional LAD during biopsy (n = 713) and (C) BG5 with additional LAD (n = 32). The number of biopsied cells ranged from 5–10 cells. Biopsied cells were tested using Next Generation Sequencing (Ion Torrent, USA).

Main results and the role of chance

The mosaicism rates for Group A, B and C were 19.0% (15/79), 23.4% (167/713) and 39.5% (15/38) respectively. Mosaicism rates of Group A and B were comparable (p = 0.4807), whilst Group C had significant higher mosaicism rate compared to Group A and B (p = 0.0238 and p = 0.0319 respectively). The mean age of Group A, B and C were 31.1, 31.4 and 27.1 respectively. The mean age between these 3 groups were not statistically significant (A vs B, p = 0.0713; A vs C, p = 0.06727; and B vs C, p = 0.4408).

Limitations, reasons for caution

Additional LAD during TE biopsy maybe be a confounding variable which affects the mosaicism rate. Moreover, the increase in mosaicism rate could be due to other unknown factors. A larger sample size is needed to confirm the results.

Wider implications of the findings: Based on our study, additional LAD during TE biopsy is not recommended as this may increase mosaicism rate. Biopsy should be done when the blastocyst has more herniated cell or when the ICM leaves the hatching point/biopsy site.

Trial registration number

Not applicable

Maintaining breast cancer care in the face of COVID-19

The battle of COVID-19 is currently at different levels of intensity in each country and even each city. The authors have prepared succinct recommendations regarding the care of patients with breast cancer, divided into phases that can easily be adapted to each units' needs and resources, and stepped up or stepped down according to escalating and de-escalating circumstances. The structure can also be transposed easily to different cancer types, enabling continued provision of best standards of care despite unprecedented stressors. Surgery must go on.

Family medicine vocational training and career satisfaction in Hong Kong

BACKGROUND

Postgraduate vocational training in family medicine (FM) is essential for physicians to build capacity and develop quality primary care. Inadequate standards in training and curriculum development can contribute to poor recruitment and retention of doctors in primary care. This study aimed to investigate: 1) the satisfaction level of doctors regarding vocational training in family medicine and associated demographics; and 2) the satisfaction level of doctors regarding their family medicine career and associated factors.

METHOD

This is a cross sectional study of all family medicine physicians across all government-funded primary care clinics (GOPCs). The study questionnaire consisted of items from a standardized and validated physician survey named the Physician Worklife Survey (PWS) (Konrad et al., Med Care, 1999). We selected three scales (7 items) relating to global job satisfaction, global career satisfaction and global specialty (family medicine) satisfaction with additional items on training and demographics. All significant variables in bivariate analyses were further examined using stepwise logistic regression.

RESULTS

Out of 424 eligible family medicine physicians, 368 physicians successfully completed the questionnaire. The response rate was 86.8%. Most participants were male (52.6%), were aged between 35 and 44 years (55.5%), were FM specialists (42.4%), graduated locally (86.2%), and had postgraduate qualifications. Eighty-two percent (82%) of participants were satisfied with their training. Having autonomy and protected time for training were associated with satisfaction with FM training. Satisfaction with family medicine as a career was correlated with physicians' satisfaction with their current job. Doctors who did not enroll in training (p < 0.001) and physicians who were older (p = 0.023) were significantly less satisfied. Stepwise multivariate regression showed that doctors who subjectively believed their training as "broad and in depth' had higher career satisfaction (p < 0.001).

CONCLUSION

Overall, the satisfaction level of physicians on current family medicine training in Hong Kong was high. Having autonomy and protected time for training is associated with higher training satisfaction levels. Perceiving FM training as "broad and in-depth" is associated with higher family medicine career satisfaction.

Spinal cord stimulation for chronic non-cancer pain: a review of current evidence and practice

Spinal cord stimulation provides analgesia through electrical stimulation of the dorsal column of the spinal cord via electrode leads placed into the epidural space. In traditional tonic stimulation, a painful sensation is replaced with paraesthesia. Spinal cord stimulation is effective in reducing neuropathic pain, enhancing function, and improving quality of life in different chronic pain conditions. Currently, there is most evidence to support its use for failed back surgery syndrome when multidisciplinary conventional management is unsuccessful. Temporary trial leads are inserted in carefully selected patients to test their responsiveness prior to permanent implantation. Newer neuromodulation modalities are now available. These include burst stimulation, high-frequency stimulation, and dorsal root ganglion stimulation. Results are encouraging to date, and they may provide superior analgesia and cover for deficiencies of traditional tonic stimulation. Although complications are not uncommon, they are rarely life threatening or permanently disabling. Nonetheless, device removal is occasionally needed.

Ductal carcinoma in-situ arising within benign phyllodes tumours

Ductal carcinoma in situ arising within a benign phyllodes tumour is a rare neoplasm of the breast. We present a case of a 19-year-old woman who had a right breast lump for six months with the above diagnosis together with a mini-review of the literature. Ultrasound revealed a 5-cm breast lump and core biopsy revealed ductal carcinoma in situ. She underwent wide local excision of the breast lump with clear margins. Final histology confirmed ductal carcinoma in situ within a fibroepithelial lesion consistent with a benign phyllodes tumour. To our knowledge, this is the youngest case of ductal carcinoma in situ arising in a phyllodes tumour to have been reported so far.

Hepatic Portal Venous Gas in a Patient with Penetrating Injuries

Hepatic portal venous gas (HPVG) refers to the branching area of low attenuation extending to within 2 cm of the liver capsule in computed tomography scan. The most common causes of HPVG are mesenteric ischaemia in adults and necrotising enterocolitis in infants. HPVG in trauma patients is mostly reported in cases of blunt abdominal trauma. We present a deceased patient who had chest and abdominal wall penetrating injuries with concomitant hypovolemic shock. A computed tomography scan revealed HPVG and pulmonary artery air emboli. The mechanism of the presentation of HPVG in this patient and the possible cause of death would be discussed. (Hong Kong j.emerg.med. 2013;20:382-384)

A Case of Acute Calcific Tendinitis of the Hand: An Uncommon Condition that is Easily Overlooked and Misdiagnosed

Acute calcific tendinitis of the hand is uncommon, yet it has a high rate of misdiagnosis as it resembles other conditions such as fractures, inflammatory and infectious causes that give rise to pain and swelling in the hand. We present a case of acute calcific tendinitis in a middle age woman affecting the extensor pollicis longus to raise awareness of this uncommon, but easily treatable cause of pain and swelling. This case was first diagnosed as septic arthritis of the interphalangeal joint of the thumb. Correct diagnosis was made after careful review of history, physical examination findings, laboratory results and radiographs. (Hong Kong j. emerg.med. 2015;22:316-319)

Association between dietary fibre intake with cancer and all-cause mortality among 15 740 adults: the National Health and Nutrition Examination Survey III

BACKGROUND

Few prospective studies have examined the longitudinal associations of total dietary fibre intake and water insoluble and soluble fibres with cancer and all-cause mortality. The present study aimed to examine these associations.

METHODS

We studied the effects of total dietary fibre intake and water insoluble and soluble fibres on cancer and all-cause mortality, using data from 15 740 adult participants [mean (SD) age: 44.53 (19.22) years, 46.60% male] in the National Health and Nutrition Examination Survey (NHANES) III, 1988-1994, who had completed a 24-h dietary recall. Death certificate data were obtained up to 2006. Participants had been followed for 13.74 years on average. Cox regression was used to estimate the hazard ratios (HRs) of total dietary, insoluble and soluble fibres on cancer and all-cause mortality, with the first quartile as the reference group, adjusted for demographics, lifestyle and dietary factors.

RESULTS

Relative to those in the first quartile of total fibre intake, only the third quartile was associated with all-cause mortality, with an adjusted HR of 0.87 [95% confidence interval (CI) = 0.79, 0.97, P = 0.021], and cancer mortality, with an adjusted HR of 0.77 (95% CI = 0.61, 0.99, P = 0.05). The third quartile of insoluble fibre intake was associated with cancer mortality, with an adjusted HR of 0.76 (95% CI = 0.60, 0.96, P = 0.023), and colorectal-anal cancer mortality (in grouped data as provided for public use), with an adjusted HR of 0.42 (95% CI = 0.19, 0.91, P = 0.03).

CONCLUSIONS

Dietary fibre showed protective benefits in terms of mortality risk. Investigating the mechanisms and components of dietary fibres underlying the different protective benefits remains an important consideration for research on fibre-mortality risk.

Effect of laser treatment on the attachment and viability of mesenchymal stem cell responses on shape memory NiTi alloy

The objectives of this study were to investigate the effect of laser-induced surface features on the morphology, attachment and viability of mesenchymal stem cells (MSCs) at different periods of time, and to evaluate the biocompatibility of different zones: laser-melted zone (MZ), heat-affected zone (HAZ) and base metal (BM) in laser-treated NiTi alloy. The surface morphology and composition were studied by scanning electron microscope (SEM) and X-ray photoemission spectroscopy (XPS), respectively. The cell morphology was examined by SEM while the cell counting and viability measurements were done by hemocytometer and 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide (MTT) colorimetric assay. The results indicated that the laser-induced surface features, such as surface roughening, presence of anisotropic dendritic pattern and complete surface Ni oxidation were beneficial to improve the biocompatibility of NiTi as evidenced by the highest cell attachment (4 days of culture) and viability (7 days of culture) found in the MZ. The biocompatibility of the MZ was the best, followed by the BM with the HAZ being the worst. The defective and porous oxide layer as well as the coarse grained structure might attribute to the inferior cell attachment (4 days of culture) and viability (7 days of culture) on the HAZ compared with the BM which has similar surface morphology.

Psychology of earthquake-induced stress cardiomyopathy, myocardial infarction and non-cardiac chest pain

AIMS

To compare psychological factors in patients presenting to hospital with earthquake-induced stress cardiomyopathy, myocardial infarction (MI) and non-cardiac chest pain. We hypothesised that patients with stress cardiomyopathy and non-cardiac chest pain would be more psychologically vulnerable than those with MI.

METHODS

Cardiology admitting staff in the week following the September 2010 Christchurch earthquake prospectively identified patients with earthquake-precipitated chest pain. Males were excluded. All consenting women met diagnostic criteria for one of the three conditions. Patients underwent a semistructured interview with a senior clinical psychologist who was blind to the cardiac diagnosis. Premorbid psychological factors, experience of the earthquake and psychological response were assessed using a range of validated tools.

RESULTS

Seventeen women were included in the study, six with stress cardiomyopathy, five with MI and six with non-cardiac chest pain. Earthquake experiences were notably similar across the groups. Patients with non-cardiac chest pain scored high on the hospital anxiety and depression scale, the health anxiety questionnaire, the Eysenck neuroticism scale and the Impact of Event scale. Women with stress cardiomyopathy scored as the most psychologically robust. Depression and extroversion scores were the same across groups.

CONCLUSION

Our hypothesis was incorrect. Women with non-cardiac chest pain following an earthquake have higher anxiety and neuroticism scores than women with either MI or stress cardiomyopathy. Stress cardiomyopathy following an earthquake is not specific to psychologically vulnerable women. The psychology of natural disaster-induced stress cardiomyopathy may differ from that of sporadic cases.

Perceptions of coronary heart disease: the development and psychometric testing of a measurement scale

Individuals' perceptions of coronary heart disease (CHD) have implications for the ways in which they respond to the disease, process risks, make decisions, and take action to reduce CHD risks. This study aimed to develop and evaluate the psychometric properties of the perceptions of coronary heart disease scale (PCS) among a Hong Kong Chinese population. A cross-sectional study was conducted using a convenient sample (n = 232) of participants recruited from a variety of catchments including public domains, a cardiac unit, and a cardiac rehabilitation and prevention center. Exploratory factor analysis identified a nine-item, two-factor model that accounted for 52.5% of the total explained variance. The two factors were the perceived risk (five items) and perceived seriousness (four items) of CHD. The PCS demonstrated good content validity; acceptable total, and subscale internal consistency (.73, .61 - .81); and significant contrast-group differences with higher levels of CHD perceptions among males (p = .002), younger participants (p < .001), and those with higher educational levels (p < .001), suggesting excellent construct validity. The newly developed PCS demonstrates acceptable psychometric properties as a short measurement scale, which supports its use in future research. Future validation of this scale is warranted.

Differences in perceptions of coronary disease among Hong Kong Chinese: implications for the societal readiness in disease prevention

Perceptions of coronary heart disease (CHD) influence individual health behavior, which is central to preventing the disease. Not enough is known about the demographic differences in perceptions of CHD among Chinese communities. This study examined these differences in the perceived seriousness and risk of CHD among Hong Kong Chinese. A self-developed questionnaire was administered to a convenient sample (n = 236). Significant differences were identified in the perceived seriousness and risk of CHD between younger and older age groups (p < 0.001) and groups with lower and higher education levels (p < 0.001), but not between genders (p > 0.05). Over 50% of participants expressed greater concern about infectious disease than about CHD, while two-thirds to over half of female, older, and less educated participants were more concerned about stroke. This study highlighted populations with lower levels of CHD perception that need increased public education. The findings have implications for the societal readiness to establishing ongoing public healthcare strategies to increase awareness of CHD.

Systemic blood pressure, arterial stiffness and pulse waveform analysis at altitude

OBJECTIVES

Systemic arterial pressure rises on acute exposure to high altitude and changes in blood pressure (BP) and endothelial function may be important in the pathogenesis of clinical syndromes occurring at high altitude.

METHODS

Arterial BP, stiffness (SI) and tone (RI) were studied over 11 days in 17 subjects (three having mild hypertension) ascending to 3,450m and 4,770m using a non-invasive, finger photoplethysmography technique.

RESULTS

At 3,450m BP rose from mean 131/75 mmHg (SD 23/12) to 145/86 (23/12) and was maintained at this level (p < 0.001). SI did not change significantly from 8.5 m/sec (2.5) to 9.7 (3.2). RI fell during the first day at 3,450m from 74.4% (7.9) to 70.5% (13.8) (NS p > 0.05) and to 69.9% (12.0) (p < 0.02) at 4,770m but then reverted to baseline. Changes in SI and RI did not relate to changes in blood pressure. Changes in both arterial stiffness and tone were similar in those who developed AMS compared with those who did not. Baseline SI tended to be higher in the three subjects with hypertension 11.1m/sec (SD 2.7)) compared with the normotensives 8.3 m/sec (SD 2.7) (NS) and baseline RI lower 74.7% (7.0) compared with the normotensives 76.5% (8.5) (NS). Changes in SI and RI at altitude in the hypertensive subjects were similar to the non-hypertensive subjects.

CONCLUSIONS

We conclude that acute exposure temporarily affected endothelial function as measured by a change in vascular tone but this did not predict the development of AMS. The rise in arterial BP was not related to changes in arterial stiffness or tone.

Translation of myelin basic protein mRNA in oligodendrocytes is regulated by integrin activation and hnRNP-K

α6β1-integrin interacts with hnRNP-K, an mRNA-binding protein, during oligodendrocyte differentiation to promote translation of MBP mRNA and myelin synthesis.

Myelination in the central nervous system provides a unique example of how cells establish asymmetry. The myelinating cell, the oligodendrocyte, extends processes to and wraps multiple axons of different diameter, keeping the number of wraps proportional to the axon diameter. Local regulation of protein synthesis represents one mechanism used to control the different requirements for myelin sheath at each axo–glia interaction. Prior work has established that β1-integrins are involved in the axoglial interactions that initiate myelination. Here, we show that integrin activation regulates translation of a key sheath protein, myelin basic protein (MBP), by reversing the inhibitory effect of the mRNA 3′UTR. During oligodendrocyte differentiation and myelination α6β1-integrin interacts with hnRNP-K, an mRNA-binding protein, which binds to MBP mRNA and translocates from the nucleus to the myelin sheath. Furthermore, knockdown of hnRNP-K inhibits MBP protein synthesis during myelination. Together, these results identify a novel pathway by which axoglial adhesion molecules coordinate MBP synthesis with myelin sheath formation.

Serial changes in the expression of breast cancer-related proteins in response to neoadjuvant chemotherapy

BACKGROUND

Tumour expression of cyclooxygenase-2 (COX-2), epidermal growth factor receptor (EGFR), erythroblastic leukaemia viral oncogene homologue-2 (ErbB2), Ki-67 and p53 in breast cancer are associated with poorer outcomes. We investigated in vivo changes of these proteins with neoadjuvant chemotherapy.

PATIENTS AND METHODS

Four core biopsies were taken from 100 breast cancer patients at baseline, during and upon completion of neoadjuvant chemotherapy. Immunohistochemical expression of these proteins were evaluated and correlated with clinicopathological features, clinical response and progression-free survival (PFS).

RESULTS

There was a statistically significant change from positivity to negativity in COX-2 expression with chemotherapy (P = 0.002), predominantly in clinical responders (P = 0.002). COX-2-positive tumours that remained positive had shorter PFS than those that turned negative. Estrogen receptor (ER)+ and COX-2+ tumours at baseline that remained COX-2+ fared worse than those that became COX-2 negative (PFS 27 versus 52 months, P = 0.002). No significant changes in IHC expression were observed for ER, progesterone receptor, ErbB2, EGFR, p53 or Ki67.

CONCLUSIONS

Chemotherapy induced change in COX-2 expression from positivity to negativity predominantly among clinical responders and is associated with longer PFS. Interaction between COX-2 and ER was observed, suggesting that some hormone receptor-positive patients may benefit from combining COX-2 inhibition with hormonal therapy.

Oxidation of Elemental Sulfur to Sulfite by Thiobacillus thiooxidans Cells

Thiobacillus thiooxidans cells oxidized elemental sulfur to sulfite, with 1 mol of O(2) consumption per mol of sulfur oxidized to sulfite, when the oxidation of sulfite was inhibited with 2-n-heptyl-4-hydroxyquinoline N-oxide.

Usage of a fixed dose of radioactive iodine for the treatment of hyperthyroidism: one-year outcome in a regional hospital in Hong Kong

OBJECTIVES

To evaluate the efficacy of a fixed dose of radioactive iodine (131-I) in the treatment of thyrotoxicosis, and to identify risk factors associated with treatment failure.

DESIGN

Retrospective study.

SETTING

Thyroid Clinic of a regional hospital in Hong Kong.

PATIENTS

Patients receiving their first dose of radioactive iodine for the treatment of thyrotoxicosis during the inclusive period September 1999 to August 2004.

MAIN OUTCOME MEASURES

Relapse rate and time to relapse.

RESULTS

A total of 113 patients received a fixed dose of 5 mCi (185 MBq), 6 mCi (222 MBq), 8 mCi (296 MBq), and 10 mCi (370 MBq) 131-I in a proportion of 1:6:71:35. At 1 year, 42 (37%) of the patients had relapsed, of which 69% received a second 131-I dose. The median time to relapse after first receiving 131-I was 4 months. At 1 year, the remaining 71 (63%) of the patients were successfully treated; 46 (41%) were euthyroid, and 25 (22%) had became permanently hypothyroid. Basal free thyroxine level and goitre size were significantly associated with a relapse rate after a single dose of 131-I; larger goitres showed a trend towards high rates of relapse. Patients pretreated with propylthiouracil had a higher rate of relapse during the first year after radioactive iodine than those pretreated with carbimazole, but the difference was not significant when combined with other pretreatment variables.

CONCLUSIONS

A single fixed dose of radioactive iodine is a simple, safe, and effective treatment for hyperthyroidism. High basal free thyroxine concentration and large goitre size are associated with higher chance of relapse. Higher radioiodine doses may be considered to improve the cure rate.

Foreign body aspiration in Hong Kong Chinese children

OBJECTIVES

To describe and compare the demographic, clinical, radiological, and bronchoscopy features and outcomes of children with foreign body aspiration in early- and late-diagnosis groups, to report the reasons for delay in diagnoses, and to determine what objects are commonly aspirated.

DESIGN

Retrospective study.

SETTING

Department of Paediatrics, Queen Elizabeth Hospital, Hong Kong.

PATIENTS

All children younger than the age of 18 years with foreign body aspiration admitted to the study hospital from 1 January 1993 to 31 May 2006.

RESULTS

Sixteen (59%) of the patients were categorised into the early-diagnosis group (correctly diagnosed foreign body aspiration<7 days of symptom onset) and 11 (41%) into the late-diagnosis group (correctly diagnosed>or=7 days after symptom onset). The common clinical manifestations of foreign body aspiration were persistent cough (100%) and history of choking (74%). Most children (82%) in the late-diagnosis group and 25% in early-diagnosis group (P=0.004) were misdiagnosed as respiratory infections and asthma. Intrabronchial granulation was more common in the late-diagnosis group (13% vs 55%, P=0.033). Peanuts and watermelon seeds accounted for 85% of the aspirations; 63% of the foreign body aspirations occurred around the Chinese New Year festival.

CONCLUSION

Foreign body aspiration is difficult to diagnose in children. Misdiagnosis as asthma and respiratory infection can delay treatment and result in intrabronchial granuloma. We therefore suggest early bronchoscopy in suspicious cases. Parents should be cautious when giving peanuts and watermelon seeds to their children.

Bilateral femoral nerve compression and compartment syndrome resulting from influenza A-induced rhabdomyolysis: a case report

Bilateral femoral nerve compression neuropathy caused by primary iliopsoas muscle pathology is rare. We report a case of extensive compartment syndrome of the right arm and both legs associated with bilateral femoral nerve palsy resulting from severe muscle swelling secondary to influenza A infection. Our objective is to alert physicians to the possible development of compartment syndrome in patients with influenza and severe myalgia. We also reviewed the literature on the pathophysiology and management of femoral nerve compression neuropathy.

Cystoid macular oedema and changes in retinal thickness after phacoemulsification with optical coherence tomography

AIMS

To study the incidence of cystoid macular oedema and changes in retinal thickness after phacoemulsification with optical coherence tomography (OCT).

METHODS

In all, 131 eyes of 131 patients were studied at the ophthalmology clinic at Tung Wah Eastern Hospital from September 2001 to October 2002. All the patients had clinical assessment and OCT preoperatively and at weeks 2, 4, and 8 postoperatively. The incidence of postoperative cystoid macular oedema (CMO) was evaluated. The foveal thickness (FT) and central 1 mm retinal thickness (CT) at different time intervals were analysed.

RESULTS

Four (3.05%) patients developed CMO after phacoemulsification, which was evident clinically and tomographically. Fluorescein angiogram confirmed leakage in all cases. For other patients, the mean preoperative FT was 189.36 +/- 26.83 microm. The mean FT, were 175.74 +/- 26.79 microm, 180.25 +/- 27.13 microm, 176.58 +/- 26.45 microm at 2 weeks, 4 weeks, and 8 weeks postoperatively, respectively. The preoperative FT was significantly thicker than those in the postoperative period. The same trend was noted for CT.

CONCLUSION

OCT is useful for detecting and confirming clinical CMO after cataract surgery; however, its use in detecting subtle changes in retinal thickness is limited by the normal variation in retinal thickness. The measurement of retinal thickness with OCT may also be affected by the status of the lens.

Prevalence study of cerebral palsy in Hong Kong children

OBJECTIVES

To investigate the prevalence of cerebral palsy in local children aged 6 to 12 years and to evaluate service utilisation by those children who attend mainstream schools.

DESIGN

Cross-sectional survey.

SETTING

Mainstream primary schools and special needs schools in Hong Kong.

PARTICIPANTS

Headmasters or headmistresses of special needs schools, and various organisations that provide services to children with cerebral palsy in the school year September 2003 to June 2004.

MAIN OUTCOME MEASURES

Prevalence of cerebral palsy and support services used by children with cerebral palsy who attend a mainstream school.

RESULTS

Of 435 572 children, 578 with cerebral palsy were identified. The overall point prevalence was 1.3 per 1000 children. The age-specific prevalence rate varied from 1.04 to 1.50 per 1000 children. Approximately 38% of children with cerebral palsy attended a mainstream school. Among those studying in special needs schools, 96% attended a school for the physically handicapped or a school for the severely mentally handicapped. Among 219 children with cerebral palsy in mainstream schools, 57 (26%) received educational support, and 134 (61%) received out-patient therapy support. Only 12% received both supporting services. No educational or therapeutic support was received by 26% of children.

CONCLUSIONS

Compared with overseas data, the low prevalence of cerebral palsy detected in local children in this investigation may be due to the differences in study design or a genuinely low prevalence. Setting up a cerebral palsy registry could help monitor the local prevalence of this childhood disability more accurately, thereby providing more reliable information for planning support services for this subgroup of children.

Effect of exercise on cerebral perfusion in humans at high altitude

The effects of submaximal and maximal exercise on cerebral perfusion were assessed using a portable, recumbent cycle ergometer in nine unacclimatized subjects ascending to 5,260 m. At 150 m, mean (SD) cerebral oxygenation (rSo2%) increased during submaximal exercise from 68.4 (SD 2.1) to 70.9 (SD 3.8) ( P < 0.0001) and at maximal oxygen uptake (V̇o2 max) to 69.8 (SD 3.1) ( P < 0.02). In contrast, at each of the high altitudes studied, rSo2 was reduced during submaximal exercise from 66.2 (SD 2.5) to 62.6 (SD 2.1) at 3,610 m ( P < 0.0001), 63.0 (SD 2.1) to 58.9 (SD 2.1) at 4,750 m ( P < 0.0001), and 62.4 (SD 3.6) to 61.2 (SD 3.9) at 5,260 m ( P < 0.01), and at V̇o2 max to 61.2 (SD 3.3) at 3,610 m ( P < 0.0001), to 59.4 (SD 2.6) at 4,750 m ( P < 0.0001), and to 58.0 (SD 3.0) at 5,260 m ( P < 0.0001). Cerebrovascular resistance tended to fall during submaximal exercise ( P = not significant) and rise at V̇o2 max, following the changes in arterial oxygen saturation and end-tidal CO2. Cerebral oxygen delivery was maintained during submaximal exercise at 150 m with a nonsignificant fall at V̇o2 max, but at high altitude peaked at 30% of V̇o2 max and then fell progressively at higher levels of exercise. The fall in rSo2 and oxygen delivery during exercise may limit exercise at altitude and is likely to contribute to the problems of acute mountain sickness and high-altitude cerebral edema.

Long-term ursodeoxycholic acid therapy for primary biliary cirrhosis: a follow-up to 12 years

BACKGROUND

It is uncertain whether ursodeoxycholic acid therapy slows down the progression of primary biliary cirrhosis, according to two meta-analyses. However, the randomized trials evaluated had only a median of 24 months of follow-up.

AIM

To evaluate long-term ursodeoxycholic acid therapy in primary biliary cirrhosis.

METHODS

We evaluated 209 consecutive primary biliary cirrhosis patients, 69 compliant with ursodeoxycholic acid and 140 untreated [mean follow-up 5.79 (s.d. = 4.73) and 4.87 (s.d. = 5.21) years, respectively] with onset of all complications documented. Comparison was made following adjustment for baseline differences according to Cox modelling, Mayo and Royal Free prognostic models.

RESULTS

Bilirubin and alkaline phosphatase concentrations improved with ursodeoxycholic acid (at 36 months, P = 0.007 and 0.018, respectively). Unadjusted Kaplan-Meier analysis showed benefit (P = 0.028), as 44 (31%) untreated and 15 (22%) ursodeoxycholic acid patients died or had liver transplantation. However, there was no difference when adjusted by Cox modelling (P = 0.267), Mayo (P = 0.698) and Royal Free models (P = 0.559). New pruritus or fatigue or other complications were not different, either before or after adjustment for baseline characteristics.

CONCLUSIONS

Long-term ursodeoxycholic acid therapy did not alter disease progression in primary biliary cirrhosis patients despite a significant improvement in serum bilirubin and alkaline phosphatase consistent with, and similar to, those seen in ursodeoxycholic acid cohorts in randomized trials.

Evaluation of two real-time polymerase chain reaction pathogen detection kits for Salmonella spp. in food

AIMS

To evaluate the LightCycler Salmonella Detection Kit and the TaqMan Salmonella Gold Detection and Quantitation Kit for the real-time PCR detection of Salmonella in various food samples.

METHODS AND RESULTS

Ready-to-eat foods and raw food samples were artificially contaminated with Salmonella serotypes. In the specificity test, bacterial DNA extracted from sample pre-enrichment culture was analysed with the detection kits performed respectively on the LightCycler Instrument or the ABI Prism 7000 Sequence Detection System. No false-positive or false-negative results were obtained, although the LightCycler system generated invalid PCR results on two occasions. In the sensitivity test using the LightCycler system, Salmonella could be detected in pre-enrichment cultures of 25-g samples inoculated with as low as 1.5 x 10(3) CFU (depending on food type), and false-negative results were obtained for samples with low inoculum levels.

CONCLUSIONS

Two commercial kits for real-time PCR detection of Salmonella were evaluated.

SIGNIFICANCE AND IMPACT OF THE STUDY

Evaluation using more food types and matrices, and foods that contain low number of Salmonella or high number of other competing bacteria, is needed before adopting the real-time PCR technique for routine food tests.

The management of superior dislocation of the patella with interlocking osteophytes--an update on a rare problem

The superior dislocation of the patella with interlocking osteophytes is a rare condition. A review of the English literature revealed only 12 reported cases. The purpose of reviewing these case reports is to highlight the unusual presentation and the injury mechanism in 2 of our patients, and to present our treatment algorithm. Closed reduction with manipulation of the patella, with or without anaesthesia, was performed without difficulty. We recommend an intermediate step of trying a regional nerve block before proceeding to general anaesthesia. Our patients had full range-of-motion after reduction and they were symptom-free after 3 years of follow-up. There were no recurrent dislocations in our patients.

Breast milk substitutes in Hong Kong

OBJECTIVE

In 1981 the World Health Assembly (WHA) adopted the International Code of Marketing of Breast Milk Substitutes (the Code) to support breastfeeding. Despite improving trends, Hong Kong has low rates of breastfeeding compared to other developed countries.

METHODS

We surveyed companies marketing breast milk substitutes in Hong Kong to determine self-reported adherence to the Code. Companies were informed that individual responses would not be published and seven of nine companies responded to the questionnaire.

RESULTS

The majority of respondents promoted infant and follow-on formula in hospitals and provided free supplies of infant formula to hospitals. Follow-on formula and weaning foods were promoted in shops and to the general public and free samples were given to mothers reflecting a belief that, despite WHA resolutions, follow-on formula is not a breast milk substitute.

CONCLUSIONS

Transnational companies should follow the Code and subsequent WHA resolutions equally in all countries.

Consensus statement on iodine deficiency disorders in Hong Kong

This article reviews the available data on the study of iodine deficiency disorders in Hong Kong and to discuss the approach towards preventing such disorders in Hong Kong. The importance of iodine and iodine deficiency disorders is described, and the available data on the dietary iodine intake and urinary iodine concentration in different populations of Hong Kong are summarised and discussed. Dietary iodine insufficiency among pregnant women in Hong Kong is associated with maternal goitrogenesis and hypothyroxinaemia as well as neonatal hypothyroidism. Borderline iodine deficiency exists in the expectant mothers in Hong Kong. Women of reproductive age, and pregnant and lactating women should be made aware and educated to have an adequate iodine intake, such as iodised salt, as an interim measure. A steering group involving all stakeholders should be formed to advise on the strategy of ensuring adequate iodine intake, including universal iodisation of salt in Hong Kong. Continuous surveillance of iodine status in the Hong Kong population is necessary.

Clinical significance and management of cervical atypical glandular cells of undetermined significance

OBJECTIVES

To assess the clinical significance of a cervical cytological diagnosis of atypical glandular cells of undetermined significance and to formulate the most appropriate management guidelines for patients with such a diagnosis.

DESIGN

Retrospective study.

SETTING

Regional hospital, Hong Kong.

PATIENTS

Seventy-two patients with diagnoses of atypical glandular cells of undetermined significance who were managed in a colposcopy clinic between January 1998 and December 1999.

MAIN OUTCOME MEASURES

Age, cytological diagnoses of atypical glandular cells of undetermined significance and its subtypes, method of evaluation, final diagnosis, and outcome after 2 years.

RESULTS

Atypical glandular cells of undetermined significance were diagnosed in 83 (0.4%) of 21 854 cervical smear samples taken during the 2-year study period. Follow-up data were available from 72 patients, whose mean age was 43 years (range, 22-69 years). Forty-three percent of these patients had significant diseases of the genital tract. Patients with the subtype diagnosis of atypical glandular cells of undetermined significance-favour neoplasia had the worst outcome, with 90% of patients having significant disease, followed by patients with atypical glandular cells of undetermined significance "not otherwise specified" (43%), and atypical glandular cells of undetermined significance-favour reactive (8%).

CONCLUSION

Patients with atypical glandular cells of undetermined significance should be investigated early and thoroughly, because many of them will have premalignant or malignant disease.

Traveling through the cancer trajectory: social support perceived by women with gynecologic cancer in Hong Kong

A qualitative research design was selected to gather data on the experiences of social support for Chinese women with gynecologic cancer. Eighteen women were recruited and interviewed at an oncology unit of a teaching hospital in Hong Kong. Content analysis of the interview data showed Chinese women with gynecologic cancer placed enormous emphasis on their human relationships. Family members were especially significant to them although not all identified their family relations as satisfactory or helpful. Their social network comprised 4 major sources, including family and friends, work and colleagues, health professionals, and religion and spiritual beliefs. Each network offered significant reciprocal relations, authoritative relations, or entrusting relations. The positive appraisal of the support function was linked to the Chinese value of food, work ethics, the Confucian and religious philosophy, whereas negative aspects of support, such as the stress of maintaining relationships and inadequate information, conjoined with the Chinese suppression of emotion and the busyness of health professionals. Future studies, including social relations as a determinant, should ensure a broad and multifunctional view of social support and acknowledge the cultural influences on the perspective of support.

Dark and bright photovoltaic spatial solitons in photorefractive crystals with positive refractive-index perturbation

We have demonstrated, for what is believed to be the first time, that in a photorefractive crystal with positive refractive-index perturbation a two-dimensional dark or bright photovoltaic spatial soliton can be formed in the same crystal by a signal beam and a background beam of different wavelengths. We discuss the conditions on the effective Glass constants and the absorption coefficients of the background and signal beams in determining the formation of the spatial soliton.

Incidence and clinical significance of inducible atrial tachycardia in patients with atrioventricular nodal reentrant tachycardia

INTRODUCTION

The purpose of this prospective study was to determine the prevalence and clinical significance of inducible atrial tachycardia in patients undergoing slow pathway ablation for AV nodal reentrant tachycardia who did not have clinically documented episodes of atrial tachycardia.

METHODS AND RESULTS

Twenty-seven (15%) of 176 consecutive patients who underwent slow pathway ablation for AV nodal reentrant tachycardia were found to have inducible atrial tachycardia with a mean cycle length of 351+/-95 msec. The atrial tachycardia was sustained in 7 (26%) of 27 patients and was isoproterenol dependent in 20 patients (74%). The atrial tachycardia was not ablated or treated with medications, and the patients were followed for 9.7+/-5.8 months. Six (22%) of the 27 patients experienced recurrent palpitations during follow-up. In one patient each, the palpitations were found to be due to sustained atrial tachycardia, nonsustained atrial tachycardia, recurrence of AV nodal reentrant tachycardia, paroxysmal atrial fibrillation, sinus tachycardia, and frequent atrial premature depolarizations. Thus, only 2 (7%) of 27 patients with inducible atrial tachycardia later developed symptoms attributable to atrial tachycardia.

CONCLUSION

Atrial tachycardia may be induced by atrial pacing in 15% of patients with AV nodal reentrant tachycardia. Because the vast majority of patients do not experience symptomatic atrial tachycardia during follow-up, treatment for atrial tachycardia should be deferred and limited to the occasional patient who later develops symptomatic atrial tachycardia.

Fulminant viral hepatitis: molecular and cellular basis, and clinical implications

Fulminant hepatic failure is defined by the sudden onset of severe liver injury accompanied by hepatic encephalopathy in an individual who previously had no evidence of liver disease. This disease causes multiple organ failure and is associated with a high mortality. The most frequently recognised cause of fulminant or subfulminant hepatic failure is viral hepatitis. Data are now emerging to support the hypothesis that, irrespective of the aetiology of fulminant hepatic failure, the host's immune response (including production of proinflammatory cytokines and mediators) contributes to microcirculatory disturbances that result in hypoxic injury and cell death (apoptosis). Impairment of the scavenger function of the reticuloendothelial cell system further contributes to reduced hepatic blood flow and ischaemic necrosis. An increased understanding of the molecular pathogenesis of fulminant hepatic failure now enables new molecular therapeutic modalities to be tested. Given the complexity of this multi-dimensional disorder, the challenge is to provide a rational basis for treatment. This might include enhancement or suppression of immune responsiveness by manipulation of endogenous cytokine synthesis or by cytokine administration and, at the same time, use of strategies to increase hepatic regeneration.

Fatigue patterns in Chinese patients receiving chemotherapy

A descriptive study was conducted to explore the patterns, risk factors and experience of fatigue in Chinese cancer patients receiving chemotherapy. Forty-two adult patients from an out-patient clinic of a university hospital in Hong Kong participated in the study. They were asked to complete a diary over a period of 2 weeks from the beginning of their chemotherapy cycle. The diary incorporated a 10cm horizontal visual analogue scale (VAS) for measuring fatigue intensity and a marked space next to the VAS for recording body temperature. Further, the Chinese version of the fatigue subscale of the Profile of Mood States was completed before the chemotherapy session, at the end of the first week post-treatment and at the end of the second week. Sociodemographic, physiological and disease/treatment-related information was obtained from the medical records. A semi-structured, open-ended interview was conducted with 18 of these patients. Most Chinese cancer patients (73.8%-90.5%) receiving chemotherapy in this study experienced fatigue. The peak level of fatigue was reported at day 3 post-treatment and it was more evident in the evenings. Female patients, patients with stage I cancer and those with nasopharyngeal carcinoma reported higher levels of fatigue (P<0.05). No relationship was found between body weight and fatigue, and some association existed between febrile illness and fatigue (P<0.001). Qualitative data affirmed the pattern of fatigue intensity and various descriptions about the experience and coping techniques of fatigue were found. Individualized and repeated assessment of patients with fatigue, as well as correcting the treatable factors that contribute to fatigue are suggested.

Osteopenia in adolescent idiopathic scoliosis: a histomorphometric study

STUDY DESIGN

Bone biopsies from iliac crest and spinous process of adolescent idiopathic scoliosis patients were obtained intraoperatively for histology and histomorphometric analysis.

OBJECTIVES

To study the histologic features of cancellous bone and to correlate the histomorphometric variables with preoperative bone mineral density in patients with adolescent idiopathic scoliosis.

SUMMARY OF BACKGROUND DATA

Low bone mineral density has been reported in adolescent idiopathic scoliosis. However, there is limited information about the histopathologic changes.

METHODS

Undecalcified and decalcified bone specimens from iliac crest and spinous process of adolescent idiopathic scoliosis patients obtained intraoperatively were stained with Goldner and hematoxylin & eosin stain, respectively. Results were correlated with bone mineral density of the lumbar spine (L2-L4) and proximal femur measured before surgery.

RESULTS

Bone histology showed significant less osteocyte count in the trabecular bone characterized with smooth and continuous borders in patients with adolescent idiopathic scoliosis. Histomorphometry confirmed the lower static parameters. The results correlated well with the decreased bone mineral density.

CONCLUSION

Bone biopsy study suggested disturbance of bone turnover in patients with adolescent idiopathic scoliosis. The abnormal metabolism might contribute to the low bone mineral density and play an important role in the etiology and pathogenesis of adolescent idiopathic scoliosis.

The impact of fatigue on Chinese cancer patients in Hong Kong

Fatigue is probably the most common symptom affecting sufferers of cancer and cancer treatments. The aim of this study was to gain an initial understanding of the impact of fatigue on Chinese cancer patients in Hong Kong. Twenty-two chemotherapy patients and 15 radiotherapy patients completed semi-structured interviews by the end of the 2nd week after commencement of their treatment. Chemotherapy patients reported greater severity of fatigue than did radiotherapy patients. Six themes emerged from the study's qualitative data that illustrated the impact of fatigue on patients' lives. These themes were: work and role functioning, daily routines, social life, mental ability, emotional status, and appetite and oral intake. The findings are discussed within the Chinese cultural context, and the need for regular assessment of fatigue in cancer patients is suggested.

Experience of palliative home care according to caregivers' and patients' ages in Hong Kong Chinese people

PURPOSE/OBJECTIVES

To identify the relationship between family caregivers' reported difficulty in managing caregiver tasks and ages of caregivers and patients.

DESIGN

Cross-sectional, descriptive survey.

SETTING

A hospice homecare program in Hong Kong.

SAMPLE

Twenty-nine Chinese family caregivers who had experienced at least weekly caregiving responsibility for more than two months and were able to read and understand Chinese.

METHODS

Respondents completed a caregiver task inventory. Four homecare nurses assisted in the distribution and collection of questionnaires.

MAIN RESEARCH VARIABLES

Caregiver tasks and age and patient age.

FINDINGS

Caregivers' age was negatively correlated with reported difficulty in overall tasks and in interpersonal ties. The patients' age was negatively correlated with reported difficulty in direct care to patients, intrapersonal tasks, and overall tasks.

CONCLUSIONS

The younger the caregiver, the more difficulty he or she experienced in the caregiving role, particularly in the maintenance of social and family ties. Caregivers of younger patients experienced more difficulty in most aspects of caregiving tasks. More research with a larger sample size is required to fully investigate the effect of age on the family caregiving experience and the validity of the caregiver task inventory.

IMPLICATIONS FOR NURSING PRACTICE

Nursing support and preparation to younger caregivers and caregivers of younger patients are suggested in the practice of palliative home care.

Measurement of the internal lasing intensity distribution of a dye-doped pendant drop

The lasing intensity distribution made inside a circular resonator formed by a dye-doped pendant drop was measured by addition of polymer particles to the dye solution to enhance the elastic-scattered light of the lasing inside the pendant drop. A theory that connects wave and ray pictures in dealing with the cavity resonance is used to calculate the internal intensity distribution. The experimental and theoretical results are in good agreement for sufficiently large densities of scattering particles, such that the cavity mode efficiency phi is approximately 1 for all resonant modes.