Functional outcome after selective dorsal rhizotomy: a retrospective case control study

PURPOSE

This study examines long-term benefit on functional outcomes and quality of life after selective dorsal rhizotomy (SDR) in children with spastic diplegia in Hong Kong.

METHOD

This is a case control study. Individuals with spastic diplegia who were at 6 to 12 years post-SDR were recruited. Age, gender, cognition, and Gross Motor Function Classification System level-matched individuals with spastic diplegia who had not undergone SDR were recruited as controls. Outcome measures included physical level, functional level, physiological level, and quality of life. All data were compared by independent t-test.

RESULTS

Individuals post-SDR (n = 15) demonstrated a significantly better range of ankle dorsiflexion in knee extension by - 5.7 ± 10.9° than the control group (n = 12). No other significant differences were observed.

CONCLUSION

SDR is a safe, one-off procedure and provides long-term reduction in spasticity with no major complications. With the heterogeneity, we did not demonstrate between-group differences in long-term functional outcomes.

Translation and validation of Cerebral Palsy Quality of Life Questionnaire-Teen in Hong Kong Chinese population [CP QoL-Teen (HK)]

Cerebral palsy (CP) is an early onset, non-progressive, neuromotor disorder. Adolescence is the transition from childhood to adulthood when changes in physical and emotional aspects and self-perception occur further imposing an impact to quality of life (QoL) in individuals with CP. Cerebral Palsy Quality of Life (CP QoL) Teen is a questionnaire examining different domains of QoL for adolescents with CP. This study is aimed at translating and validating self-report and proxy-report CP QoL-Teen (HK). Prior approval of translation has been obtained. Forward and backward translations were performed following standardized translation procedures. Participants and their caregivers were asked to complete self-report and proxy-report CP QoL-Teen (HK), and Child Health Questionnaire (CHQ). Internal consistency and test-retest reliability were assessed by Cronbach's alpha and intraclass correlation coefficient (ICC), respectively. Concurrent validity was evaluated by Spearman's rank correlation between subscales of CP QoL-Teen (HK) and CHQ as well as expanded and revised version of Gross Motor Function Classification System (GMFCS-E&R). Ninety-six participants completed the study. Of these, twenty participants completed CP QoL-Teen (HK) twice. Cronbach's α of CP QoL-Teen (HK) ranged from 0.84 to 0.95 suggesting excellent internal consistency. Moderate to excellent test-retest reliability were demonstrated in all subscales of CP QoL-Teen (HK) (self-report: ICC = 0.46-0.8; proxy-report: ICC = 0.40-0.72, p < 0.05). Weak to moderate association between subscales of CP QoL-Teen (HK) and CHQ (self-report: rs = 0.24-0.61; proxy-report: rs = - 0.41-0.60) was reported.

CONCLUSION

This study showed that CP QoL-Teen (HK) has good psychometric properties. It is a valid and reliable tool to assess quality of life of adolescents with CP.

WHAT IS KNOWN

• Cerebral Palsy Quality of life-Teen (CP QoL-Teen) is a validated tool with strong psychometric properties and clinical utility in gauging the QoL in adolescents with CP during their transition from childhood to adulthood when changes in physical and emotional aspects and self-perception occur. Yet, a locally validated tool is lacking in measuring the QoL for adolescents with CP in Hong Kong.

WHAT IS NEW

• The Chinese translated version CP QoL-Teen (HK) is a valid and reliable tool to assess quality of life of adolescents with CP tailoring to the local cultural and social background with good psychometric properties being demonstrated.

A cross-sectional assessment of food practices, physical activity levels, and stress levels in middle age and older adults' during the COVID-19 pandemic

Aim

This cross-sectional study examined how the COVID-19 pandemic impacted the food practices, physical activity (PA) levels, and stress levels of aging adults ages 40 years and older from seven states. It also explored to what extent the COVID-19 outcomes were affected by the social determinants of health (SDH).

Subject and methods

Respondents (n = 1250) completed an online survey. Descriptive statistics were used to analyze the sociodemographic attributes and COVID-19 responses while the multiple llinear regression (MLR) test evaluated to what extent the SDH variables measured were associated with the reported COVID-19 impacts food practices, PA levels, and stress levels.

Results

Respondents were mostly White (75.9%), married (58.7%), age 60 years and older (61.8%), with a high school education or higher (97.4%). Most of the respondents (85.8%) live in areas that respondents perceived as supportive of health and well-being opportunities for older adults. Nearly one-half of the respondents reported maintaining their pre-pandemic grocery shopping/food buying frequency (44.7%) and PA levels (48.1%). However, 48.6% reported being "somewhat or very stressed" due to the pandemic. Findings revealed that the COVID-19 impacts on food-buying, PA levels, and stress levels were significantly influenced by age, gender, race, education, location, community, nutritional risk, quality of life, food security, and income (p < 0.05).

Conclusion

These findings provide valuable information as we continue to confront the impact the COVID-19 pandemic has had on the health and well-being of aging adults. We can use this information to inform future public health programming interventions and opportunities.

Virtual Delivery of Fresh Conversations, a SNAP-Ed Program: Participant Perceived Impact and Satisfaction

This four-month study evaluated the virtual delivery of Fresh Conversations (FC). Participants were community-residing Iowans ages 60+ years. They were placed in one of four meeting groups based on location and participant preference: Zoom™, Adobe Connect^®, group-based Zoom™ meeting, and teleconference. Participants were invited to complete a post-meeting online survey. Data analyses were completed using data from the first survey completed by each participant (n = 115). Descriptive statistics assessed response frequencies for all questions. Chi-Square and Mann-Whitney U tests assessed the differences between groups. Overall, participants were "satisfied/very satisfied" (72.1%), learned something new (85.2%), and intended to make behavior change (79.1%); no differences were detected by the group for satisfaction or reported impacts. Only 24.3% reported technical difficulties; the Adobe Connect^® group reported the most difficulties (p = .004). These findings suggest virtual delivery of FC is well-received and perceived to be effective by participants.

396 A 6-Month Audit of Initial Diabetic Foot Assessment and Documentation for Patients Undergoing Major Lower Limb Amputations in An Orthopaedics Ward

Aim

To determine if adequate diabetic foot assessment and documentation were done at the Orthopaedics ward for patients undergoing a below-knee amputation (BKA) or above-knee amputation (AKA).

Method

Retrospective data from August 2019 to January 2020 were taken from paper documentation and e-records from the Orthopaedics ward and operation theatre. Diabetic foot assessments were based on the ASEANPlus guidelines for diabetic foot wounds which included foot inspection (for dermatological or musculoskeletal abnormalities), vascular (palpation of dorsalis pedis and posterior tibial pulses, ABSI measurement) and neurological assessments (testing of sensation and ankle reflexes). The assessments were deemed “adequate” or “inadequate” based on the information found on documentation.

Results

Only 67/81 data pieces were available for analysis (AKA=26, BKA=41), with an average age of 60 years. Inspection of the foot was most adequately assessed and documented (100%), followed by vascular and neurological assessment. For vascular assessment, palpation of pulses was done in 94% cases, and ABSI was performed in 76%. For neurological assessment, assessment of sensation was performed in 55%, while ankle reflexes were only assessed and documented in 25% cases.

Conclusions

Overall, the local practice had poor documentation of diabetic foot assessment, especially in vascular and neurological assessments. Possible reasons for poor practice include lack of guidance for incoming junior doctors starting their Orthopaedics rotation, and subsequently, the lack of skills and confidence in performing said assessments. Measures that could be done to improve the quality of practice include teaching key examinations to junior staff and having closer monitoring of notes documentation during ward rounds.

Altered Fibrinolysis in DVT: Influence of Site of Sampling

Alteration of the fibrinolytic system is considered to be important in the development of deep venous thrombosis (DVT). Using specific assays for tissue plasminogen activator (t-PA) activity, t-PA inhibitor (PAI) and t-PA antigen, we measured these activities in 16 women who developed DVT during their pregnancies. A group of 24 healthy females of comparable age was studied as controls. PAI was increased in 87% of these patients compared to the healthy controls. In some of these patients a defect in release of t-PA from vascular endothelium was found as well. The site at which blood was sampled for analysis appeared to be an important criterion in the ex vivo assessment of functional t-PA reserve and PAI levels, though relatively less so for the latter measurement. The unaffected lower limbs, relative to the unaffected upper limbs, showed an increase in PAI and a demonstrable decrease in t-PA release, both representing increased risk factors for rethrombosis. The affected lower limbs showed similar but more accentuated changes in these parameters.

Willingness for deceased organ donation under different legislative systems in Hong Kong: population-based cross-sectional survey

INTRODUCTION

Under the current opt-in system, the deceased organ donation rate remains low in Hong Kong. An opt-out system and an opt-in system combined with organ allocation priority (ie, priority to donors as transplant recipients) have been proposed to encourage willingness among the general population towards deceased organ donation. This study aimed to compare willingness, and its determinants, across these three legislative systems.

METHODS

A random telephone survey of Hong Kong permanent residents aged ≥18 years was conducted between August and October 2016 using an anonymous questionnaire. Willingness towards deceased organ donation was compared between the legislative systems with McNemar's test. Determinants of willingness were tested by logistic regression.

RESULTS

The proportion of those willing to consider deceased organ donation under the current opt-in system would significantly increase after combining it with allocation priority (64.5% vs 73.4%; P=0.018). "Fairness or reciprocity" was the major reported reason underlying the increase. In contrast, willingness would decrease after introducing the opt-out system (60.1%), although not significantly (P=0.336). The reduction might be attributable to a "belief of being forced to donate". Under the allocation priority system, reduced willingness to donate was associated with advanced age, lower educational attainment, and lower monthly household income. Under the opt-out system, reduced willingness was associated with being married, having a lower household income, and distrust of local government.

CONCLUSIONS

An opt-in system with allocation priority could induce willingness to donate, whereas an opt-out system may reduce willingness. The findings have implications for policy-making and promotion of organ donation.

Severe Hypertension and Bradycardia Secondary to Midodrine Overdose

The objective of this case is to describe the pharmacokinetics and toxicity of midodrine in overdose. A 20 year old female ingested up to 350 mg midodrine while recovering in hospital from another overdose. She developed vomiting and severe hypertension (blood pressure [BP], 210/100 mmHg). Remarkable findings included a heart rate with a range of 43-60 beats/min, spontaneous respirations (20 breaths/min), and oxygen saturations of >95 % on FiO2 25 %, and a GS of 8. She was admitted to intensive care and had a normal non-contrast CT brain. She was treated with a glyceryl trinitrate patch (5 mg) and observed for 36 h with subsequent BP reduction to 124/81 mmHg and improved in conscious state. Midodrine and desglymidodrine concentrations were measured with liquid chromatography tandem mass spectrometry and were detected with 2-h post-ingestion at concentrations of 158.4 and 169.7 ng/mL, respectively. The parent drug concentrations rapidly decreased with an elimination of half-life of 1.6 h, and the metabolite initially increased and then decreased. The peak in blood pressure appeared to coincide with peak metabolite concentrations. Midodrine in overdose can potentially cause severe hypertension and reflex bradycardia but given its short half-life treatment with vasodilator agents and supportive care is sufficient.

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

OBJECTIVES

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

METHODS

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

RESULTS

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

CONCLUSIONS

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

Calculation of energy recovery and greenhouse gas emission reduction from palm oil mill effluent treatment by an anaerobic granular-sludge process

Conventional aerobic and low-rate anaerobic processes such as pond and open-tank systems have been widely used in wastewater treatment. In order to improve treatment efficacy and to avoid greenhouse gas emissions, conventional treatment can be upgraded to a high performance anaerobic granular-sludge system. The anaerobic granular-sludge systems are designed to capture the biogas produced, rendering a potential for claims of carbon credits under the Kyoto Protocol for reducing emissions of greenhouse gases. Certified Emission Reductions (CERs) would be issued, which can be exchanged between businesses or bought and sold in international markets at the prevailing market prices. As the advanced anaerobic granular systems are capable of handling high organic loadings concomitant with high strength wastewater and short hydraulic retention time, they render more carbon credits than other conventional anaerobic systems. In addition to efficient waste degradation, the carbon credits can be used to generate revenue and to finance the project. This paper presents a scenario on emission avoidance based on a methane recovery and utilization project. An example analysis on emission reduction and an overview of the global emission market are also outlined.

Clinics in diagnostic imaging (129). Posterior cruciate ligament ganglion cyst

Ganglion cysts arising from the posterior cruciate ligament (PCL) of the knee are rare. We describe a 21-year-old Chinese woman who presented with right knee pain following a twisting injury six months prior. Her pain was exacerbated by squatting, although her range of knee motion was full. Magnetic resonance imaging showed a lobulated, well-defined, T1-hypointense and T2-hyperintense, septated cystic mass arising from the posterior aspect of the PCL. The diagnosis of a PCL ganglion cyst was confirmed by computed tomography-guided aspiration of the cyst. Due to persistent mild knee pain, the patient eventually underwent arthroscopic decompression of the ganglion cyst. The clinical features, diagnosis and management of PCL ganglion cysts are discussed.

Emergent properties in optically bound matter

Sub-micron particles have been observed to spontaneously form regular two-dimensional structures in counterpropagating evanescent laser fields. We show that collective properties of large numbers of optically-trapped particles can be qualitatively different to the properties of small numbers. This is demonstrated both with a computer model and with experimental results. As the number of particles in the structure is increased, optical binding forces can be sufficiently large to overcome the optical landscape imposed by the interference fringes of the laser beams and impose a different, competing structure.

Dorsal dislocation of the metacarpophalangeal joint of the thumb: a case report

Dorsal dislocation of the metacarpophalangeal joint of the thumb is uncommon. We report the case of a 15-year-old patient with a complex dislocation of the left thumb who underwent open reduction after several attempts at closed reduction failed. At 2-month follow-up, full range of movement was regained; strength and pinch grip were comparable to that of the uninjured hand. The patient defaulted subsequent follow-up.

Clinicopathologic significance of bcl-2 expression in the surgical treatment of oral tongue carcinoma

AIM

There is still controversy on the incidence of positive expression of bcl-2 and its prognostic significance for oral tongue carcinoma patients who are treated by surgery. The present study aims at resolving the controversy on the clinicopathologic significance of bcl-2 in a well selected group of patients who satisfy the recruitment criteria: (1) oral tongue carcinoma, (2) squamous cell carcinoma, (3) primary surgical treatment.

METHOD

Bcl-2 expression was studied by immunohistochemistry on glossectomy specimens of 73 patients. The expression of bcl-2 was correlated with clinicopathologic data.

RESULTS

Of the 73 tumours, 11% had positive expression of bcl-2. Bcl-2 expression was not significantly correlated with tumour grade, stage, nodal metastasis and survival.

CONCLUSION

Bcl-2 expression played a minor role in oral tongue carcinoma. It had no significant correlation with tumour grade, stage and nodal metastasis. It also had no prognostic value on survival for patients who were treated by primary surgery.

Survival of infants with spina bifida: a population study, 1979-94

This study aimed to investigate the survival of infants born with spina bifida between 1979 and 1994 from the population-based Metropolitan Atlanta Congenital Defects Program (MACDP) and to identify clinical and demographic factors associated with survival. Survival status was obtained from MACDP records and the National Death Index. Survival rates were calculated using the Kaplan-Meier method. Risk factors potentially associated with survival were examined by the log-rank test. We assessed the independent effect of risk factors using the Cox proportional hazards model. Overall, 78.4% of children with spina bifida survived during the study period. Of the 235 infants born with spina bifida, 87.2% survived the first year of life. Survival to age 1 for the 1979-83, 1984-88 and 1989-94 birth cohorts was 82.7%, 88.5% and 91.0% respectively. In multivariable analysis, factors associated with increased mortality were low birthweight (<2500 g) (vs. > or =2500g, relative risk (RR) 2.3 [95% CI 1.1, 4.9]) and high lesions (vs. low lesions, RR 3.4 [95% CI 1.6, 7.1]). This study suggests a continuous improvement in survival among children born with spina bifida in Atlanta. Demographic and clinical factors are associated with length of survival. This information is useful for both clinicians and families who need to plan for the long-term care of these children.

Impact of folic acid fortification of the US food supply on the occurrence of neural tube defects

CONTEXT

Daily consumption of 400 microg of folic acid before conception and during early pregnancy dramatically reduces the occurrence of neural tube defects (NTDs). Before food fortification, however, only an estimated 29% of US reproductive-aged women were taking a supplement containing 400 microg of folic acid daily. The US Food and Drug Administration authorized addition of folic acid to enriched grain products in March 1996, with compliance mandatory by January 1998.

OBJECTIVE

To evaluate the impact of food fortification with folic acid on NTD birth prevalence.

DESIGN, SETTING, AND POPULATION

National study of birth certificate data for live births to women in 45 US states and Washington, DC, between January 1990 and December 1999.

MAIN OUTCOME MEASURE

Birth certificate reports of spina bifida and anencephaly before fortification (October 1995 through December 1996) compared with after mandatory fortification (October 1998 through December 1999).

RESULTS

The birth prevalence of NTDs reported on birth certificates decreased from 37.8 per 100 000 live births before fortification to 30.5 per 100 000 live births conceived after mandatory folic acid fortification, representing a 19% decline (prevalence ratio [PR], 0.81; 95% confidence interval [CI], 0.75-0.87). During the same period, NTD birth prevalence declined from 53.4 per 100 000 to 46.5 per 100 000 (PR, 0.87; 95% CI, 0.64-1.18) for women who received only third-trimester or no prenatal care.

CONCLUSIONS

A 19% reduction in NTD birth prevalence occurred following folic acid fortification of the US food supply. However, factors other than fortification may have contributed to this decline.

Epidemiology of headache in Hong Kong primary-level schoolchildren: questionnaire study

OBJECTIVE

To collect and analyse epidemiological data on childhood headache in the Hong Kong community.

DESIGN

Questionnaire study.

SETTING

Three primary schools, Hong Kong.

PARTICIPANTS

Two thousand, one hundred and twenty pupils from 2156 replied to the questionnaire survey. One hundred and twenty-four pupils who were identified to have suspected recurrent headache were invited to a follow-up medical consultation.

MAIN OUTCOME MEASURES

Age-groups and prevalence of tension-type and migraine headache, using the diagnostic criteria of the International Headache Society.

RESULTS

The overall prevalence of headache in the 2120 respondents was 2.8%. The prevalence of tension-type headache, migraine, probable migraine, and unclassified headache were 1.2%, 0.5%, 0.7%, and 0.5%, respectively. The age-specific prevalence of headache from the age of 6 to 13 years showed a steadily increasing trend from childhood to the early teens.

CONCLUSION

Headache is a common complaint for children, although it may be underrecognised. Further study will be beneficial for providing better management of headache in this population.

Visual field plasticity in a female with right occipital cortical dysplasia

Brain plasticity refers to its ability to recover after damage. Visual field plasticity is not well recognized. We report a 12-year-old female who first presented with recurrent seizures and was subsequently found to have a large, right occipital cortical dysplasia on magnetic resonance imaging. Her visual field by Goldmann perimetry was totally normal. Visual-evoked potential studies revealed the left hemifield P100 response was detected maximally at the right temporal and parietal regions. A weak but reproducible right hemifield P100 response was located at the right medial skull base. Functional magnetic resonance imaging with flashlight stimulation revealed cerebral activity mainly at the right posterior temporal and parietal lobes and left occipital lobe. These studies suggested that the left hemifield function was located at the right posterior temporal and parietal lobes. The left occipital lobe may also have been reorganized, with a P100 vector pointing out from its inferiomedial base. We reviewed other related reported cases. We believe that visual-evoked potential studies and visual functional magnetic resonance imaging should be performed more liberally for recognition of visual field plasticity.

General method for HPLC purification and sequencing of selected dsDNA gene fragments from complex PCRs generated during gene expression profiling

Gene expression profiling using an AFLP-based technique generates a large number of gene fragments that require identification by sequencing. The DNA fragments vary in length from about 50-500 bp. Ion-pair reversed-phase HPLC can be used to purify selected double-stranded DNA fragments that represent differentially expressed genes. The gene fragments are sequenced directly after vacuum drying of the collected HPLC fractions.

Prevention of neural-tube defects with folic acid in China. China-U.S. Collaborative Project for Neural Tube Defect Prevention

BACKGROUND AND METHODS

Periconceptional administration of folic acid can reduce a woman's risk of having a fetus or infant with a neural-tube defect. As part of a public health campaign conducted from 1993 to 1995 in an area of China with high rates of neural-tube defects (the northern region) and one with low rates (the southern region), we evaluated the outcomes of pregnancy in women who were asked to take a pill containing 400 microg of folic acid alone daily from the time of their premarital examination until the end of their first trimester of pregnancy.

RESULTS

Among the fetuses or infants of 130,142 women who took folic acid at any time before or during pregnancy and 117,689 women who had not taken folic acid, we identified 102 and 173, respectively, with neural-tube defects. Among the fetuses or infants of women who registered before their last menstrual period and who did not take any folic acid, the rates of neural-tube defects were 4.8 per 1000 pregnancies of at least 20 weeks' gestation in the northern region and 1.0 per 1000 in the southern region. Among the fetuses or infants of the women with periconceptional use of folic acid, the rates were 1.0 per 1000 in the northern region and 0.6 per 1000 in the southern region. The greatest reduction in risk occurred among the fetuses or infants of a subgroup of women in the northern region with periconceptional use who took folic acid pills more than 80 percent of the time (reduction in risk, 85 percent as compared with the fetuses or infants of women who registered before their last menstrual period and who took no folic acid; 95 percent confidence interval, 62 to 94 percent) [corrected]. In the southern region the reduction in risk among the fetuses or infants of women with periconceptional use of folic acid was also significant (reduction in risk, 41 percent; 95 percent confidence interval, 3 to 64 percent).

CONCLUSIONS

Periconceptional intake of 400 microg of folic acid daily can reduce the risk of neural-tube defects in areas with high rates of these defects and in areas with low rates.

Nausea during pregnancy and congenital heart defects: a population-based case-control study

The authors investigated the possible association between a mother's nausea during pregnancy and her child's risk for a congenital heart defect using data from the population-based Atlanta Birth Defects Case-Control Study conducted in 1982-1983. Case infants (n = 998) had nonsyndromic congenital heart defects and control infants (n = 3,029) had no congenital defects. Nausea during pregnancy (NP) was graded in eight levels of "severity" based on its onset, frequency, and duration. Level 1, the most severe NP, was associated with a lower risk for a congenital heart defect in the child (odds ratio (OR) = 0.81, 95% confidence interval (CI) 0.67-0.99) compared with no nausea. The lower risk tended to disappear with less severe levels of nausea, and the trend was statistically significant. Overall, early NP (levels 1 to 4 combined) with use of antinausea medication, particularly Bendectin (doxylamine, dicyclomine (dropped from the formulation in 1976), pyridoxine (vitamin B6)), was associated with a lower risk for congenital heart defects compared with: 1) absence of nausea (OR = 0.67, 95% CI 0.50-0.92), and 2) nausea without medication use (OR = 0.70, 95% CI 0.50-0.94). The results suggest that pregnancy hormones and factors or, alternatively, a component of Bendectin (most probably pyridoxine) may be important for normal heart development. These findings outline potential areas for future research on and prevention of congenital heart defects.

Association between allele 1 of T102C polymorphism, 5-hydroxytryptamine 2a receptor gene and schizophrenia in Chinese males in Singapore

The T102C polymorphism at the 5-hydroxytryptamine 2a receptor (5HTR2a) gene was studied in 101 Chinese male schizophrenics and 103 controls. Genotyping revealed a predominance of allele 1 among schizophrenics. This is in contrast to previous reports in Caucasians and Japanese which showed an association of allele 2 of this polymorphism with schizophrenia.

From maximum surgical blood ordering schedule to unlimited computer crossmatching: evolution of blood transfusion for surgical patients at a tertiary hospital in Hong Kong

The maximum surgical blood ordering schedule (MSBOS) was developed to permit efficient use of blood stocks and reduce blood wastage due to outdating. Success of the MSBOS required full cooperation between surgeons, anaesthetists, blood bankers and house officers. However, clinical staff sometimes disregarded the system or distrusted the ability of the laboratory to provide blood in an emergency. This led to frustration and wastage of laboratory staff effort. We developed a computer crossmatch system that could overcome the shortcomings of the MSBOS. The advantages of this system are reported.

Cranial computed tomography in children with acute lymphoblastic leukemia after prophylactic treatment with cranial radiation therapy and intrathecal methotrexate

BACKGROUND AND METHODS

Thirty-one children with acute lymphoblastic leukemia (ALL) who had received cranial radiation therapy (CrRT) and five concomitant doses of intrathecal methotrexate (IT MTX) for central nervous system prophylaxis (CNSP) and who had an event-free survival exceeding 5 years had cranial computed tomography (Cr CT) examination. The fractional dose for 21 of them was 1.5 Gy. The interval between the completion of CNSP and the time of Cr CT ranged from 5 to 8.5 years, with a median of 5 years 2 months.

RESULTS

Unlike the previous reports in the literature that 9-77% of children with ALL who had received Cr RT 18 Gy and IT MTX as CNSP had CT scan abnormalities, in this study no patient had CT scan abnormalities.

CONCLUSIONS

Our results might be attributable to the fractional dose of Cr RT being adequate, the IT chemotherapy being suitable, and the systemic chemotherapy not being intensive.

Parosteal osteosarcoma: a case report

Parosteal osteosarcoma is a low-grade malignant tumor arising from the periosteum. It involves mainly adults of third to sixth decades and the favorite site is the posterior aspect of distal femoral metaphysis. Microscopically, it is composed of woven to lamellar bone trabeculae within spindle cell stroma. We present a case of parosteal osteosarcoma that has very well-formed lamellar bone trabeculae and fat marrow under microscopic examination. Without the help of radiologic study, it is impossible to make the diagnosis of parosteal osteosarcoma.

Renal osteodystrophy

The term "renal osteodystrophy" is used to include skeletal disorders of patients with chronic renal failure: osteitis fibrosa, osteomalacia, osteosclerosis, osteoporosis and the frequently associated extraskeletal calcifications. It is the chronic glomerular disease with phosphate retention and resultant hyperphosphatemia on one hand and deficient 1,25 (OH)2 D3 and resultant hypocalcemia on the other to induce secondary hyperparathyroidism. The three most common causes of chronic renal failure in our patients are chronic glomerulonephritis, diabetic nephropathy, hypertensive nephropathy in decreasing frequency, polycystic renal disease occurs in five patients. Other miscellaneous causes include nephrotic syndrome, chronic pyelonephritis, systemic lupus erythematosus, periarteritis nodosa, interstitial nephritis and renal stones. The bone changes are similar in primary and secondary hyperparathyroidism and the incidence of brown tumor is about 3% in the former and 1.5 to 1.7% in the latter. We present one among the 94 dialyzed patients who has long-standing severe chronic renal failure from polycystic kidney disease and develops brown tumor in the mid ulna after 7 years on maintenance hemodialysis. The incidence of brown tumor in our series is about 1.1%. Because of increased longevity of the dialyzed patients, brown tumor from secondary hyperparathyroidism is now more commonly observed. Hyperphosphatemia with serum calcium-phosphate products exceeding plasma solubility of 60 to 75 mg/dl may induce soft tissue and vascular calcification. This explains the much higher incidence of soft tissue calcification in secondary than primary hyperparathyroidism; two of our patients with generalized Monckeberg's type arterial calcification and multiple periarticular calcifications in five patients have been observed.(ABSTRACT TRUNCATED AT 250 WORDS)

Effect of blood transfusion on acid base, glucose and electrolyte status in very low birth weight infants

The effect of citrate phosphate dextrose (CPD) blood transfusion on the acid base, glucose and electrolyte status of VLBW infants was studied in infants aged 1-7, 8-20 and greater than 20 days; a 4th group composed of infants greater than 20 days subjected to a second transfusion was also studied. All the infants remained clinically well during and after the transfusion. Only the infants in the group 1-7 days experienced a significant fall in ionic Ca and PO2. No significant change in all the other parameters studied was observed. In the other groups of infants studied, the changes observed were not significant, and became less with increasing age and repeat transfusion. VLBW infants apparently tolerate CPD blood transfusion well.

Detection of tumour antigens in sera of patients with hepatocellular carcinoma using monoclonal antibodies

A total of 70 serum samples taken from patients with hepatocellular carcinoma (HCC), acute viral hepatitis and cirrhosis and normal individuals were tested in a binding inhibition immunofluorescence assay using 5 mouse monoclonal antibodies (2G9, 3H11, 3H12, 1C7, 3H5) specific for hepatoma cells. Seven out of the 30 HCC sera (23.3%) inhibited the binding of one of these antibodies, 3H11. This detection of antigen 3H11 or antigens of similar structure in HCC sera was significantly more frequent than in control sera (1/40 = 2.5%) (Fisher's exact test, p = 0.009; df = 1, relative risk calculated by the odds ratio in a 2 x 2 table = 12.0). The presence of this antigen was unrelated to the hepatitis B surface antigen and alphafetoprotein status. Thus it would be of value particularly for the detection of hepatitis B negative or alphafetoprotein negative liver cancers.

Immunogenicity and safety of low doses of recombinant yeast-derived hepatitis B vaccine

The immunogenicity and safety of recombinant yeast-derived hepatitis B vaccine given in doses of 0.6 microgram, 1.25 microgram, 2.5 micrograms and 5.0 micrograms were studied in 4 comparable groups of children aged 1-12 years. All children received three doses of vaccine at time 0, 1 month and 5 months. Immunogenicity appeared to be satisfactory in all 4 groups of children. In the early phase of the study, a dose-response relationship was observed but there was no significant difference in the geometric mean titre among all 4 groups for any period studied. Antibody levels peaked at 9 months, declining thereafter. The geometric mean titre one year after the first vaccine dose was not significantly lower than that at the peak (9 months) in any individual group studied. The second year geometric mean titre was similar in all 4 groups and lower than that of the first year. Sero-conversion with antibody titres greater than or equal to 10 mIU/ml was 100% in the 5.0 micrograms group and greater than 90% in the other 3 groups. There were no adverse reactions of any significance. The immunogenicity of recombinant yeast-derived hepatitis B vaccine was found to be adequate even at as low a dosage as 0.6 microgram when administered in a 3-dose regimen.

The prevalence of hepatitis B virus markers in dental personnel in Singapore

A seroepidemiological survey of the prevalence of hepatitis B virus (HBV) markers was conducted in a group of 693 dental personnel in Singapore where HBV infection is endemic. The overall prevalence of HBsAg (4.5%) and anti-HBc (29%) was no higher than that in the general population. However, dentists had a significantly higher HBsAg prevalence (11.4%) compared with that in the general population (4.2%) (P less than 0.01) and of other categories of dental personnel (3.1%) (P less than 0.001). Similarly, the anti-HBc prevalence of the dentists (45.6%) was significantly higher than that of the general population (29.7%) (P less than 0.01) and of other categories of dental personnel (25.7%) (P less than 0.0001). It appears that dentists in the endemic area have a definite occupational risk of acquiring HBV infection.

Altered fibrinolysis in DVT: influence of site of sampling

Alteration of the fibrinolytic system is considered to be important in the development of deep venous thrombosis (DVT). Using specific assays for tissue plasminogen activator (t-PA) activity, t-PA inhibitor (PAI) and t-PA antigen, we measured these activities in 16 women who developed DVT during their pregnancies. A group of 24 healthy females of comparable age was studied as controls. PAI was increased in 87% of these patients compared to the healthy controls. In some of these patients a defect in release of t-PA from vascular endothelium was found as well. The site at which blood was sampled for analysis appeared to be an important criterion in the ex vivo assessment of functional t-PA reserve and PAI levels, though relatively less so for the latter measurement. The unaffected lower limbs, relative to the unaffected upper limbs, showed an increase in PAI and a demonstrable decrease in t-PA release, both representing increased risk factors for rethrombosis. The affected lower limbs showed similar but more accentuated changes in these parameters.

Effect of recombinant gamma interferon on hepatocellular carcinoma cell lines

The effects of recombinant gamma interferon (rIFN-gamma) were tested on 4 different hepatocellular carcinoma (HCC) cell lines PLC/PRF/5, HepG2, Hep3B and SK-Hep1. Exposure of these HCC cells to 100/ml of rIFN-gamma induced high levels of major histocompatibility complex (MHC) class I expression on their membrane, but not class II antigens. The enhancement of class I antigen synthesis occurs without a corresponding increase in synthesis of HBsAg by HBV genome positive PLC/PRF/5 and Hep3B cells. A 5 log dose of rIFN-gamma also did not trigger the integrated HBV genome into active replication as indicated by a lack of HBcAg and HBeAg synthesis. These results point to a possible role for the use of rIFN-gamma to enhance tumour cell recognition by the host immune system via the increased MHC class I expression.

Prostaglandin synthesis and its inhibition by cyclic AMP and forskolin in postpartum follicles of the guppy (Poecilia reticulata)

Prostaglandin synthesis in vitro and its inhibition by dibutyryl cyclic AMP and forskolin were examined in postpartum follicles of the guppy. The follicles were cultured for up to 72h under chemically-defined conditions, and the synthesis of prostaglandins was determined by radioimmunoassay. The results show unequivocally that the ovarian follicles devoid of embryos can synthesize PGE and PGF from both endogenous precursors as well as added arachidonic acid. That this could be inhibited by indomethacin is indicative of active synthesis rather than release of preformed prostaglandins. Dibutyryl cAMP and forskolin also inhibited prostaglandin synthesis in a dose-dependent manner, as did 3-isobutyl-l-methylxanthine. A similar effect was also evident in vitellogenic oocytes surrounded by follicle layers at the yolk-globule stage of development. While the physiological significance of this action of the cyclic nucleotide remains uncertain at this stage, it is hypothesized that it could explain the non-occurrence of ovulation in this viviparous fish soon after final oocyte maturation.

The prevalence of antibody to hepatitis A virus in Singapore

Sera collected from 1, 630 healthy children and adults aged between six months and 55 years during the period 1984 to 1985 were tested for hepatitis A virus (HAV) immunoglobulin G antibody by enzyme immunoassay. The over all antibody prevalence rate was 31.8%. It increased from 0% in children under five years old to 15.5% in adolescents and young adults (15 to 24 years) and reached the highest level of 88.2% in adults over 55 years of age. No statistically significant differences in the overall prevalence by sex and ethnic group were observed. None of the 938 samples tested for HAV immunoglobin M antibody was positive. Compared with the data in 1975, the survey showed that the level of exposure of Singapore children to HAV was declining as the result of vast socio-economic progress made during the past decade.

Growth, biochemical and haematological status of very low birth weight premature infants

Very low birth weight (less than 1500 g) premature (less than 33/52) infants were studied while fed on Alprem for the first 10 weeks of life. After initial weight loss due to inadequate intake, weight gain was satisfactory and steady. The need for sodium and potassium exceeded the amount supplied in the milk only in the initial period. However, the serum calcium and phosphate levels were slightly decreased especially in the later period of the study, accompanied by marked elevation in alkaline phosphatase values. Alprem appears to be able to sustain adequate growth in small prematures though early sodium and potassium, and late calcium and phosphate supplements seem necessary.

Immunocytochemical localization of testosterone in human hepatocellular carcinoma

A study of 10 hepatoma patients was carried out for the detection and localization of oestrogen, progesterone, testosterone, and their corresponding binding sites in liver tumour cells using immunoperoxidase and immunofluorescent techniques on histopathological sections and cultured monolayers. None of the hepatomas was positive for progesterone and its receptor; one was positive for oestrogen and its receptor; five were positive for testosterone and its receptor. Oestrogen, testosterone and their respective receptors localized predominantly to the cytoplasm of hepatoma cells. The results obtained in this investigation reveal an association between testosterone and human liver cancer which may be useful in the selection and monitoring of liver cancer patients to future hormonal therapy.