Subacute Combined Degeneration of the Spinal Cord

We report a case of a 79-year-old gentleman presenting with numbness of both hands. A magnetic resonance imaging of the cervical spine demonstrated features suggestive of subacute combined degeneration of the spinal cord which was further supported by a low serum vitamin B12. This is a reversible condition if early diagnosis can be made and vitamin B12 therapy promptly given. Delayed treatment can result in irreversible neurological impairment.

Alpha-2 adrenergic stimulation triggers Achilles tenocyte hypercellularity: Comparison between two model systems

The histopathology of tendons with painful tendinopathy is often tendinosis, a fibrosis-like condition of unclear pathogenesis characterized by tissue changes including hypercellularity. The primary tendon cells (tenocytes) have been shown to express adrenoreceptors (mainly alpha-2A) as well as markers of catecholamine production, particularly in tendinosis. It is known that adrenergic stimulation can induce proliferation in other cells. The present study investigated the effects of an exogenously administered alpha-2 adrenergic agonist in an established in vivo Achilles tendinosis model (rabbit) and also in an in vitro human tendon cell culture model. The catecholamine producing enzyme tyrosine hydroxylase and the alpha-2A-adrenoreceptor (α_2A AR) were expressed by tenocytes, and alpha-2 adrenergic stimulation had a proliferative effect on these cells, in both models. The proliferation was inhibited by administration of an α_2A AR antagonist, and the in vitro model further showed that the proliferative alpha-2A effect was mediated via a mitogenic cell signaling pathway involving phosphorylation of extracellular-signal-regulated kinases 1 and 2. The results indicate that catecholamines produced by tenocytes in tendinosis might contribute to the proliferative nature of the pathology through stimulation of the α_2A AR, pointing to a novel target for future therapies. The study furthermore shows that animal models are not necessarily required for all aspects of this research.

Mechanical force modulates scleraxis expression in bioartificial tendons

Following tendon injury, cartilage, bone and fat metaplasia are often observed, making the optimization of tenocyte differentiation an important clinical goal. In this study we examined the effect of static and cyclic mechanical loading on the expression of genes which play a role in tenocyte differentiation and function, namely scleraxis (Scx) and Type I collagen (Col1a1), and determined the effect of varying mechanical parameters including (1) static vs dynamic load, (2) increasing strain magnitude, (3) inclusion of 10 s rest periods, and (4) increasing cycle number. Cyclic loading resulted in a greater increase of tenocyte gene expression than static loading over 3 weeks in culture. Increasing strain levels potentiated the induction of tenocyte genes. The insertion of a 10 s rest periods further enhanced tenocyte gene expression, as did increasing repetition numbers. These results suggest that mechanical signaling exerts an important influence on the expression of genes which play a role in determining the tendon phenotype. Further work is required to confirm and extend these findings in primary cells such as resident tendon progenitor/stem cells, in order to provide an improved understanding of biology from which optimized rehabilitation programs can be developed.

Depressive symptoms and behavioural health risks in young women attending an urban sexual health clinic

BACKGROUND

Adolescence is a time of increased health risk behaviours and depressive symptoms and disorders. Most young people with depressive disorders, however, are not under the care of specialist child and adolescent mental health services, and there is increasing interest in identifying alternative appropriate settings which are acceptable for young people and may attract those at high risk for depressive disorders.

AIM

To assess depressive and behavioural health risks in attendees to a sexual health clinic (SHC) for young people.

METHOD

Cross-sectional controlled study of women attending a SHC and school attendees, using questionnaires on depressive symptoms and mental health problems, sexual activity and substance use.

RESULTS

115/178 attendees 14-19 years old completed questionnaires. In the comparison between 66 women aged 16-18 years and 49 socio-demographically group-matched school controls, SHC attendees reported higher levels of sexual activity and substance use. They were significantly more at risk for depression (20/65 or 30% vs. 4/46 or 8%; chi(2)P < 0.01) on the Beck Depression Inventory, for emotional (12/66 or 18% vs. 1/49 or 2%; chi(2)P < 0.01), hyperactivity (11/66 or 16% vs. 2/46 or 4%; chi(2)P < 0.05) and conduct (8/66 or 12% vs. 0/49; chi(2)P < 0.05) problems on the Strengths and Difficulties Questionnaire. High depressive scores were significantly associated with a history of self-harm, earlier alcohol use and having tried cannabis, but not with sexual risk behaviours. Earlier age at first sexual intercourse was linked to higher sexual and substance use risks.

CONCLUSION

We have found high levels of depressive symptoms among attendees to a SHC for young people, which seem an appropriate setting for screening and providing guidance for depression and other health risk behaviours.

Idiopathic inflammatory demyelinating disorders after acute transverse myelitis

Acute transverse myelitis (ATM) is commonly para-infectious. Recurrent ATM occurs in connective tissue diseases (CTD), infective myelitis and idiopathic inflammatory demyelinating disorders (IIDD) including multiple sclerosis (MS) and neuromyelitis optica (NMO). Previous studies might include NMO and idiopathic recurrent transverse myelitis (IRTM) as MS. The aim was to study the outcome of patients after a first attack of idiopathic ATM. Idiopathic ATM patients over a 6-year period were retrospectively studied. Known causes of myelopathy were excluded. Among 32 patients studied, 20 (63%) had single ATM attack upon follow up for 39-93 months, three developed recurrent ATM related to CTD (two systemic lupus erythematosus and one anti-Ro antibody positive) and nine (28.1%) developed recurrent neuroinflammation compatible with IIDD. Among IIDD patients, three had NMO, two restricted variant of NMO, three IRTM and one classical MS. NMO, its variant and IRTM had mean spinal MRI abnormality of 3.7, 2.1 and 3.9 vertebral segments respectively while non-recurrent ATM had 1.6 vertebral segments. Four (80%) of the five patients with NMO or its variant had poor neurological prognosis versus only one (5%) of non-recurrent ATM patients. IRTM patients had advanced mean onset age, 62 years vs. 43 years for non-recurrent ATM patients. In IIDD patients presenting with ATM as first attack of neuroinflammation, NMO and its variant (56%) were most frequent, then IRTM (33%), with classical MS (11%) the rarest. As long-term treatments for NMO are different from MS, early recognition of NMO and its variant is important for prevention of serious neurological deficits.

BACH1 is a DNA repair protein supporting BRCA1 damage response

The link between defects in BRCA1 and breast cancer development may be best understood by deciphering the role of associated proteins. BRCA1 associated C-terminal helicase (BACH1) interacts directly with the BRCA1 C-terminal BRCT repeats, which are important for BRCA1 DNA repair and are mutated in the majority of BRCA1 familial cancers. Thus, BACH1 is a likely candidate for mediating BRCA1 DNA repair and tumor suppression functions. Although previous evidence using overexpression of a dominant negative BACH1 has suggested that BACH1 is involved in BRCA1-DNA repair function, our results using BACH1 deficient cells provide direct evidence for involvement of BACH1 in DNA repair as well as for localizing BRCA1. Following DNA damage BACH1 is modified by phosphorylation, displays a BRCA1-like nuclear foci pattern and colocalizes with gamma-H2AX. Given that the BACH1/BRCA1 complex is unaltered by DNA damage and the intensity of BRCA1 foci is diminished in BACH1 deficient cells, BACH1 may serve to not only facilitate DNA repair, but also maintain BRCA1 in DNA damage foci.

An epidemiological study of motor neuron disease in Hong Kong

Worldwide, the incidence of motor neuron disease (MND) has been increasing steadily over recent decades. We reported a follow-up epidemiology study of MND in this locality. We identified the subjects from the computer database of the government hospital system between 1 January 1997 and 31 January 2002 by searching the ICD code starting from 335.xx. Every retrieved case or their records were reviewed and validated by neurologist(s) of the responsible regional hospitals which the patients attended. One hundred and twenty cases from seven regional hospitals (serving 48.05% of the HKSAR population) were identified, validated and confirmed to be MND or related diseases. Ninety-eight new cases were diagnosed during the study period. Average age of onset was 58.76 years; SD 14.12 (28-89) years. Male to female ratio was 1.72:1. Peak age of onset was 60-64 years without sex difference. The adjusted incidence rate was 0.60/100,000/year. The adjusted point prevalence at the prevalence date (31 January 2001) was 3.04/100,000. Despite the incidence and prevalence of MND among Hong Kong Chinese, it remained low compared to worldwide figures, and our data suggested a significant rise of MND or related disease in the last decade. A territory-wide prospective epidemiological study is indicated.

Association of novel single nucleotide polymorphisms in the calcium channel alpha 1 subunit gene (Ca(v)1.1) and thyrotoxic periodic paralysis

Thyrotoxic (hypokalemic) periodic paralysis (TPP) is a frequent complication of thyrotoxicosis among Chinese men. To determine the genetic association of TPP, we studied 97 male TPP patients, 77 Graves' disease patients without TPP, and 100 normal male subjects. Mutations of the voltage-dependent calcium channel (Ca(v)1.1), sodium channel (Na(v)1.4), and potassium channel (K(v)3.4), and association of the microsatellite markers on chromosome 1 in the region of the Na/K-ATPase subunits alpha1, alpha2, and beta1 were studied. None of the TPP patients carried the known mutations in Ca(v)1.1, Na(v)1.4, and K(v)3.4 genes. There was no association of TPP with the microsatellite markers that mapped to 1p13, 1q21-23, and 1q22-25. We detected 12 single nucleotide polymorphisms (SNPs) in Ca(v)1.1 in our population, of which three were novel. Significant differences in the SNP genotype distribution between TPP compared with Graves' disease controls and normal controls were seen at the 5' flanking region nucleotide (nt) -476 (P = 0.02), intron 2 nt 57 (P < 0.01), and intron 26 nt 67 (P < 0.001). Because these SNPs lie at or near the thyroid hormone responsive element, it is possible that they may affect the binding affinity of the thyroid hormone responsive element and modulate the stimulation of thyroid hormone on the Ca(v)1.1 gene.

Body part asymmetry in partial seizure

Clinically differentiating between localisation related and generalised epilepsy is important because it carries significant implications for planning diagnostic management strategy. Asymmetry of body parts such as toes, popliteal crease levels, thumbs, cubital crease levels, and forehead and facial structures, are common in patients with localisation related epilepsy syndromes. We retrospectively studied 337 patients with seizure disorders. Body part asymmetry was routinely documented. Fifty-six were excluded because of non-epileptic seizures, pure psychiatric disorders, non-epileptic neurological disorders, brain tumours and strokes. The relationship between clinically detectable body asymmetry (BA) and the electro-anatomic characteristics of their epilepsy was explored. Body asymmetry was found in 88 out of 282 cases, in which 64 (73.5%) suffered from localisation related epilepsy. Among localisation related epilepsy, BA were found in 41.5% (n=64/154) of patients. In contrast, only 18.75% (n=24/128) of patients with generalised seizure disorders showed similar findings (P<0.0001). Among patients with partial onset seizures, lateralisation of BA was concordant with their seizure origin in 75.9% (n=41/54) and discordant in 24.1% (n=13/54). Investigation results of 10 partial epilepsy cases were non-lateralising at the time of study. Peak age of onset of concordant case was 0-5 years old while discordant group was 6-15 years old. We conclude that BA in patients with seizure disorder is a useful clue to diagnosis of localisation related seizure and may provide clues for lateralising seizure origin in partial onset seizures.

A prevalence study of epilepsy in Hong Kong

OBJECTIVES

To examine epidemiological data on epilepsy for the Hong Kong west region. DESIGN. Descriptive study.

SETTING

Epilepsy clinic, university teaching hospital, Hong Kong.

PATIENTS AND METHODS

The epilepsy clinic of Queen Mary Hospital manages the majority of adult patients (aged 15 years or older) with chronic seizure disorders resident in the Hong Kong west area with an adult population of 475,900. All patients underwent electroencephalography examination and each subject was independently assessed by two epileptologists for diagnosis and classified according to the International League Against Epilepsy recommendations.

RESULTS

Seven hundred and thirty-six patients (female, 42.9%; male, 57.1%; mean age, 40.8 years; standard deviation, 13.6 years) with epilepsy were enrolled in the study. The prevalence rate of active epilepsy in the population 15 years or older was estimated at 1.54 per 1000 on 1 January 2002. Two hundred and eighty-five (38.7%) patients had idiopathic epilepsy syndromes, 100 (13.6%) had cryptogenic epilepsy, and 285 (38.7%) had a remote symptomatic aetiology. Seizure type was partial in 408 (55.4%) patients and generalised in 285 (38.7%). Thirty-one (4.2%) patients had a positive family history. Idiopathic generalised epilepsy syndromes described as common in the literature, such as juvenile myoclonic epilepsy and childhood absence epilepsy, were infrequently seen at 0.68% and 0.95% of cases, respectively.

CONCLUSIONS

This study provides baseline data for epilepsy service development and research in Hong Kong. The prevalence rate of active epilepsy in this Chinese, adult population was low compared with that reported in other developed countries. Further population-based epidemiological research is indicated to confirm the prevalence of seizure disorders in this locality.

Tuberculous meningitis with tuberculomata presenting as postpartum pyrexia of unknown origin

A35-year-old Chinese woman had primary infertility as a result of bilateral fallopian tube blockage. She had had uterine fibroids resected 3 years previously. Her precious pregnancy via in-vitro fertilization was complicated by premature rupture of amniotic membrane at 18 weeks' gestation. Two doses of betamethasone 12 mg were given at 29 weeks' gestation, and fetal bradycardia was noted on the next day. A baby girl was delivered by emergency caesarean section. The patient had a high swinging fever following the delivery. Extensive investigations for postpartum pyrexia were normal or negative. She was given courses of broad-spectrum antibiotics for 4 weeks before she developed mental dullness and right partial ptosis. On the next day, she became disorientated with left hemiplegia. Examination also revealed left-sided neglect, dysphasia, conjugate gaze deviation to the right, and left homonymous hemianopia. Computed tomography (CT) of the brain revealed a left temporal hypodense area (Figure 1a). Lumbar puncture revealed the following CSF findings: opening pressure of 34 cmH2O, protein level of 3.8 g/litre, glucose level of 2.1 mM (serum 6.4 mM), cell count of 30 × 106/litre (56% lymphocytes, 40% neutrophils, 4% monocytes), and red cell count of 11 × 106/litre. Other CSF tests were negative.

Lateral temporal hyperperfusion in postictal psychosis assessed by 99mTc-HMPAO SPECT

Postictal psychosis is a rare complication of epileptic seizure characterized by reversible psychotic symptoms after flurries of seizure attack. It has been attributed to a phenomenon similar to Todd's paralysis without definitive proof. We studied regional cerebral blood flow (rCBF) of six patients with postictal psychosis by (99m)Tc-HMPAO SPECT scan. Baseline rCBF was compared with the rCBF during postictal psychosis. An asymmetry index (ASI) was calculated as 200 x [(ipsilateral ROI count density - contralateral ROI count density)/(ipsilateral ROI count density + contralateral ROI count density)] %. Significant differences could be found between ASIs during postictal psychosis and interictal state SPECT scan over the lateral temporal neocortex region (P = 0.017). Although hyperperfusion abnormality in SPECT can be found in Todd's paralysis, such findings are more commonly found in cerebral hyperactivity conditions. Taking into account the clinical characteristics of postictal psychosis, namely a preceding lucid interval and crescendo-decrescendo clinical course, these may be an alternative psychopathogenic mechanism for the development of postictal psychosis.

Folding and assembly of the Escherichia coli succinyl-CoA synthetase heterotetramer without participation of molecular chaperones

Succinyl-CoA synthetase of Escherichia coli (alpha 2B2 subunit structure) has been shown to fold and assemble without participation by molecular chaperones. Renaturation experiments showed that purified bacterial chaperone GroEL has no effect on the folding and assembly of the active tetrameric enzyme. When isolated 35S-labeled alpha or beta subunits were incubated with GroEL in the absence of ATP, there was no complex formation between the subunits and GroEL. These in vitro results were confirmed by in vivo analysis of the folding and assembly of newly synthesized succinyl-CoA synthetase subunits. When expression of the subunits was induced in E. coli strains that bear GroEL or GroES temperature-sensitive mutations, the assembly of active succinyl-CoA synthetase was not affected as the temperature was raised to 43 degrees C. These and other observations are discussed that indicate that folding and assembly of succinyl-CoA synthetase may be independent of assistance by any chaperone.

Road rage: a psychiatric phenomenon?

BACKGROUND

Road rage is a concept recently popularised by the press. An association with psychiatric illness is implied from reports of such drivers being "mad". Previous literature has demonstrated a link between road traffic accidents and mental illness. This study examines the relationship between road rage and psychiatric morbidity. It aims to estimate the prevalence of road rage by self-report and elucidate demographic and psychiatric factors associated with road rage.

METHOD

This is a cross-sectional study of attendees at general practice clinics that examines self-reported road rage and psychiatric morbidity. Assessment was based on the total score on the Clinical Interview Schedule (revised version; CIS-R), Aggression Questionnaire, Screening Test for Comorbid Personality Disorders, Alcohol Use Disorders Identification Test and Life Events Schedule.

RESULTS

Fifty-three percent of 131 subjects reported a recent incident of road rage. Perpetrator and victim groups differed from controls. Perpetrators had increased aggression scores and psychiatric morbidity. There was a strong association with male sex and illicit drug use, and a strong negative association with driving experience. A weaker association was found with youth. Victims showed increased psychiatric morbidity and were more likely than perpetrators to seek help for emotional problems. Life events stress, social class, alcohol use and personality disorder had no significant effect.

CONCLUSION

There is an association between road rage and psychiatric morbidity.

Assessment of enterotoxin production by Yersinia enterocolitica and identification of a novel heat-stable enterotoxin produced by a noninvasive Y. enterocolitica strain isolated from clinical material

Twenty-eight clinical isolates of Yersinia enterocolitica were investigated for their abilities to produce heat-stable enterotoxin (YST). All 21 invasive strains (serogroup O3 biotype 4) carried the previously described gene for YST (yst), with toxin detectable in culture supernatants from 20 strains. One of seven noninvasive, biotype 1A strains also had enterotoxic activity, despite failure to hybridize with a probe for yst. The toxin produced by this noninvasive (serogroup O6) strain resembled YST in terms of molecular size, heat stability, and solubility in methanol. It differed from YST, however, with respect to regulation of its production by temperature and its mechanism of action, which did not appear to involve cyclic GMP.

Traumatic hyphaema. Outcome and management

The files of 206 patients who had sustained a hyphaema as a result of a contusion injury and had been admitted to Sydney Eye Hospital between January 1979 and December 1981 were reviewed. Most hyphaemas were small (189 or 91.7 per cent), occupying less than one-third of the volume of the anterior chamber. Fifteen patients had a secondary haemorrhage while in hospital and nine of these had a small hyphaema.

Prevalence of gestational diabetes and macrosomic newborns in a Mexican population

Prevalence of gestational diabetes was investigated in 693 pregnant patients between the 24th and 28th wk of gestation. A glucose screening test (GST) was performed with a 50-g glucose load, followed by a blood sample 1 h later. Patients with glucose levels greater than 140 mg/dl 1 h after the GST were scheduled for a full oral glucose tolerance test (OGTT). One hundred seven patients had an abnormal GST, and 30 patients (4.3%) were diagnosed as having gestational diabetes mellitus (GDM). The percentage of GDM increased significantly when glucose levels were greater than 180 mg/dl to a maximum of 84.61% when glucose levels were greater than 200 mg/dl. Also, patient age was directly related to GDM, which increased in incidence to 20% when patients greater than 26 yr had an abnormal GST. After delivery, newborn weights were compared between those born to mothers with GDM (n = 30) and those born to mothers with an abnormal GST (n = 77). Patients with an abnormal GST and normal OGTT had 12 (15.58%) macrosomic and 2 premature newborns. However, patients with GDM had 5 (16.66%) macrosomic and no premature newborns. Patients with a normal GST had 7.33% of the macrosomic newborns. There was no perinatal mortality in newborns of GDM mothers; only 1 of the 5 macrosomic newborns presented transient hypoglycemia. Evaluation of 26 GDM patients was possible after delivery, disclosing 3 (11.53%) with non-insulin-dependent diabetes mellitus and 5 (19.23%) with impaired glucose tolerance. These results showed 4.3% undetected GDM in our population and no differences in the proportion of macrosomic newborns between those born to mothers with GDM and those born to mothers with an abnormal GST.

Management of external gastrointestinal fistulas with glucose and lipids

Thirty-one patients with 35 external gastrointestinal fistulas were initially managed conservatively with total parenteral nutrition. Patients received the centrally infused glucose system or the peripherally infused lipid system, or both systems, in sequence. Eighteen of the fistulas closed spontaneously, and nine patients died. Eleven of the 15 fistulas managed exclusively with the lipid system closed spontaneously. The results of this retrospective study attest, in general, to the value of total parenteral nutrition and, in particular, to the value of the lipid system which appears equally effective, at least in a subset of patients with fistulas.

Parenteral nutrition with lipids

Total parenteral nutrition with a peripherally administered fat emulsion as the major calorie source appears to be efficacious and safe. Such a regimen complements rather than replaces the glucose system an an important adjunct in patient therapy. The lipid system obviates the necessity for central venous administration, the major disadvantage of the glucose system, while the latter provides a greater caloric density.

Spironolactone and acute mountain sickness

Thirteen adults trekking in Nepal in 1974 to altitudes between 4,300 m and 5,500 m remained free from acute mountain sickness while taking spironolactone as a prophylactic measure. Two years previously five of these adults trekking at similar altitudes, but without treatment, had suffered from acute mountain sickness. The regime used was spironolactone in a dosage of 25 mg three times a day for two days preceding and during the periods spent at altitudes above 3,000 m.