microbeMASST: a taxonomically informed mass spectrometry search tool for microbial metabolomics data

microbeMASST, a taxonomically informed mass spectrometry (MS) search tool, tackles limited microbial metabolite annotation in untargeted metabolomics experiments. Leveraging a curated database of >60,000 microbial monocultures, users can search known and unknown MS/MS spectra and link them to their respective microbial producers via MS/MS fragmentation patterns. Identification of microbe-derived metabolites and relative producers without a priori knowledge will vastly enhance the understanding of microorganisms' role in ecology and human health.

The thrombin generation capability of the Chacma baboon (Papio ursinus): implications for haemostatic disease models

Baboon models are often used to investigate haemostatic diseases, such as acquired thrombotic thrombocytopenic purpura or bacterial sepsis-induced disseminated intravascular coagulation, and their potential treatment with novel drugs. Thrombin generation is vital for these models, and an important potential therapeutic target. We investigated the thrombin generation profile of the Chacma baboon (Papio ursinus - a common pre-clinical model) including the effects of sex and ABO blood group. Thrombin generation curves, lag times, peak heights, times-to-peak, velocity indexes and Endogenous Thrombin Potentials (ETPs) of 40 adult Chacma baboons were assessed and compared with normal human plasma, using a low concentration of tissue factor (1 pM) and phospholipids. Reference intervals were calculated, and results compared between O and non-O ABO blood groups, and between males and females. Lag times of all baboons fell within the human reference interval. Most animals (n = 32; 80%) had times-to-peak above, and velocity indexes and peak heights markedly below (n = 27; 68%) the human range. However, 97.5% of baboons had an ETP above the human reference interval, indicating greater overall thrombin generation. ABO blood group had no effect, but males (n = 14; 35%) had less potent thrombin generation than females (n = 26; 65%), with significantly longer lag times (p = 0.0475), lower peak thrombin concentrations (p = 0.0203), and lower ETPs (p = 0.0238). Chacma baboons have greater overall endogenous thrombin generation potentials than humans, which is even more prominent in females. This should be considered when designing future baboon model experiments involving the haemostatic system, or when evaluating novel therapies in these animals.

A Taxonomically-informed Mass Spectrometry Search Tool for Microbial Metabolomics Data

MicrobeMASST, a taxonomically-informed mass spectrometry (MS) search tool, tackles limited microbial metabolite annotation in untargeted metabolomics experiments. Leveraging a curated database of >60,000 microbial monocultures, users can search known and unknown MS/MS spectra and link them to their respective microbial producers via MS/MS fragmentation patterns. Identification of microbial-derived metabolites and relative producers, without a priori knowledge, will vastly enhance the understanding of microorganisms' role in ecology and human health.

Prophylaxis is the new standard of care in patients with haemophilia

Randomised controlled clinical trial evidence on prophylaxis as optimal care for patients with haemophilia was generated more than a decade ago. However, this knowledge has not translated into clinical practice in South Africa (SA) owing to many barriers to prophylaxis. These include the high treatment burden imposed by prophylaxis (frequent injections two to four times a week), the need for intravenous access to administer replacement clotting factor therapies, and the higher volume of clotting factor required compared with episodic treatment. The recently introduced non-factor therapies in haemophilia care have addressed many of these barriers. For example, emicizumab, which is currently the only globally approved non-factor therapy, can be administered subcutaneously less frequently (weekly, fortnightly or every 4 weeks) and has led to global adoption of prophylaxis as the standard of care in haemophilia by the bleeding disorders community. Haemophilia A is the most prevalent clotting factor deficiency in SA, with >2 000 people diagnosed to date. However, only a few of these patients are currently on prophylaxis. In this 'In Practice' article, we review the rationale for prophylaxis, outline its goals and benefits, and provide evidence-based guidance on which haemophilia patients should be prioritised for emicizumab prophylaxis. This consensus guidance facilitates the adoption of prophylaxis as a national policy and the new standard of care in haemophilia in SA.

The effects of streptokinase in a Chacma baboon (Papio ursinus) model of acquired thrombotic thrombocytopenic purpura

TTP is a life-threatening disorder with limited pharmaceutical treatment options. Recently, the potential of streptokinase in the treatment of acquired TTP was demonstrated in humans in vitro, and in vivo in a mouse model. We aimed to determine the in vitro and in vivo effects of streptokinase in an established Papio ursinus model of acquired TTP. In vitro: VWF activities & multimer patterns and thromboelastograms were assessed with increasing concentrations of streptokinase. In vivo: After induction of TTP, escalating streptokinase doses (ranging from 50,000 to 900,000 IU) were administered, and the effects of streptokinase assessed on peripheral blood counts, fibrinolysis, VWF activities & multimer patterns and thromboelastograms. In an extension of the study, high-dose streptokinase (1,500,000-3,000,000 IU) was administered to another baboon. After spiking, fibrinolysis with loss of large VWF multimers was observed at [2200 IU/mL]-roughly equivalent to 1,500,000 IU. However, administration of escalating intravenous streptokinase doses had no in vivo effect on the TTP phenotype, and in vivo increases in plasmin activity were mild when compared with baseline, even at high doses. Minimal effect on VWF multimer patterns was observed but only at doses ≥ 1500,000 IU. Streptokinase is not effective in resolving TTP in a Papio ursinus model of TTP, possibly due to limited activation of the baboon fibrinolytic system. Modifications to this model, the use of alternative higher animal models, or alternative thrombolytics, should be considered to establish proof-of-concept.

Multi-targeted directed ligands for Alzheimer's disease: design of novel lead coumarin conjugates

Alzheimer's Disease (AD) is a neurodegenerative disease characterized by central nervous system insults with progressive cognitive (memory, attention) and non-cognitive (anxiety, depression) impairments. Pathophysiological events affect predominantly cholinergic neuronal loss and dysfunctions of the dopaminergic system. The aim of the current study was to design multi-targeted directed lead structures based on the coumarin scaffold with inhibitory properties at two key enzymes in disease relevant systems, i.e. acetylcholinesterase (AChE) and monoamine oxidase B (MAO-B). Conventional and microwave synthetic methods were utilized to synthesize coumarin scaffold-based novel morpholino, piperidino, thiophene and erucic acid conjugates. Biological assays indicated that the coumarin-morpholine ether conjugate BPR 10 was the most potent hMAO-B inhibitor. The coumarin-piperidine conjugates BPR 13 and BPR 12 were the most potent inhibitors of eeAChE at 100 μM and 1 μM, respectively. Molecular modelling studies were conducted with Accelrys^® Discovery Studio^® V3.1.1 utilising the published hMAO-B (2V61) and hAChE (4EY7) crystal structures. Compound BPR 10 occupies both the entrance and substrate cavities of the active site of MAO-B. BPR 13 resides in both the peripheral anionic site (PAS) and the catalytic anionic site (CAS) of hAChE. This study demonstrated that the coumarin scaffold serves as a promising pharmacophore for MTDLs design.

Endoscopy-based management decreases the risk of postoperative recurrences in Crohn’s disease

AIM: To investigate whether an endoscopy-based management could prevent the long-term risk of postoperative recurrence.

METHODS: From the pathology department database, we retrospectively retrieved the data of all the patients operated on for Crohn’s disease (CD) in our center (1986-2015). Endoscopy-based management was defined as systematic postoperative colonoscopy (median time after surgery = 9.5 mo) in patients with no clinical postoperative recurrence at the time of endoscopy.

RESULTS: From 205 patients who underwent surgery, 161 patients (follow-up > 6 mo) were included. Endoscopic postoperative recurrence occurred in 67.6%, 79.7%, and 95.5% of the patients, respectively 5, 10 and 20 years after surgery. The rate of clinical postoperative recurrence was 61.4%, 75.9%, and 92.5% at 5, 10 and 20 years, respectively. The rate of surgical postoperative recurrence was 19.0%, 38.9% and 64.7%, respectively, 5, 10 and 20 years after surgery. In multivariate analysis, previous intestinal resection, prior exposure to anti-TNF therapy before surgery, and fistulizing phenotype (B3) were postoperative risk factors. Previous perianal abscess/fistula (other perianal lesions excluded), were predictive of only symptomatic recurrence. In multivariate analysis, an endoscopy-based management (n = 49/161) prevented clinical (HR = 0.4, 95%CI: 0.25-0.66, P < 0.001) and surgical postoperative recurrence (HR = 0.30, 95%CI: 0.13-0.70, P = 0.006).

CONCLUSION: Endoscopy-based management should be recommended in all CD patients within the first year after surgery as it highly decreases the long-term risk of clinical recurrence and reoperation.

ICARUSS, the Integrated Care for the Reduction of Secondary Stroke trial: rationale and design of a randomized controlled trial of a multimodal intervention to prevent recurrent stroke in patients with a recent cerebrovascular event, ACTRN = 12611000264987

BACKGROUND

The majority of strokes, both ischaemic and haemorrhagic, are attributable to a relatively small number of risk factors which are readily manageable in primary care setting. Implementation of best-practice recommendations for risk factor management is calculated to reduce stroke recurrence by around 80%. However, risk factor management in stroke survivors has generally been poor at primary care level. A model of care that supports long-term effective risk factor management is needed.

AIM

To determine whether the model of Integrated Care for the Reduction of Recurrent Stroke (ICARUSS) will, through promotion of implementation of best-practice recommendations for risk factor management reduce the combined incidence of stroke, myocardial infarction and vascular death in patients with recent stroke or transient ischaemic attack (TIA) of the brain or eye.

DESIGN

A prospective, Australian, multicentre, randomized controlled trial.

SETTING

Academic stroke units in Melbourne, Perth and the John Hunter Hospital, New South Wales.

SUBJECTS

1000 stroke survivors recruited as from March 2007 with a recent (<3 months) stroke (ischaemic or haemorrhagic) or a TIA (brain or eye).

RANDOMIZATION

Randomization and data collection are performed by means of a central computer generated telephone system (IVRS).

INTERVENTION

Exposure to the ICARUSS model of integrated care or usual care.

PRIMARY OUTCOME

The composite of stroke, MI or death from any vascular cause, whichever occurs first.

SECONDARY OUTCOMES

Risk factor management in the community, depression, quality of life, disability and dementia.

STATISTICAL POWER

With 1000 patients followed up for a median of one-year, with a recurrence rate of 7-10% per year in patients exposed to usual care, the study will have at least 80% power to detect a significant reduction in primary end-points

CONCLUSION

The ICARUSS study aims to recruit and follow up patients between 2007 and 2013 and demonstrate the effectiveness of exposure to the ICARUSS model in stroke survivors to reduce recurrent stroke or vascular events and promote the implementation of best practice risk factor management at primary care level.

Rift valley Fever in Kruger national park: do buffalo play a role in the inter-epidemic circulation of virus?

Rift Valley fever (RVF) is a zoonotic mosquito-borne virus disease of livestock and wild ruminants that has been identified as a risk for international spread. Typically, the disease occurs in geographically limited outbreaks associated with high rainfall events and can cause massive losses of livestock. It is unclear how RVF virus persists during inter-epidemic periods but cryptic cycling of the virus in wildlife populations may play a role. We investigated the role that free-living African buffalo (Syncerus caffer caffer) might play in inter-epidemic circulation of the virus and looked for geographic, age and sex patterns of Rift Valley fever virus (RVFV) infection in African buffalo. Buffalo serum samples were collected (n = 1615) in Kruger National Park (KNP), South Africa, during a period of 1996-2007 and tested for antibodies to RVF. We found that older animals were more likely to be seropositive for anti-RVFV antibody than younger animals, but sex was not correlated with the likelihood of being anti-RVFV antibody positive. We also found geographic variation within KNP; herds in the south were more likely to have acquired anti-RVFV antibody than herds farther north - which could be driven by host or vector ecology. In all years of the study between 1996 and 2007, we found young buffalo (under 2 years of age) that were seropositive for anti-RVFV antibody, with prevalence ranging between 0 and 27% each year, indicating probable circulation. In addition, we also conducted a 4-year longitudinal study on 227 initially RVFV seronegative buffalo to look for evidence of seroconversion outside known RVF outbreaks within our study period (2008-2012). In the longitudinal study, we found five individuals that seroconverted from anti-RVFV antibody negative to anti-RVFV antibody positive, outside of any detected outbreak. Overall, our results provide evidence of long-term undetected circulation of RVFV in the buffalo population.

Use of the passive lower lingual arch in the management of anterior mandibular crowding in the mixed dentition

Leeway space preservation in the mixed dentition is a well-documented method of space management. In the mandibular arch it may be saved for utilisation in the correction of minor anterior crowding by the placement of a passive lower lingual arch (LLA) during the transition from the mixed dentition to the permanent dentition.

[Management of stroke in sub-Saharan Africa: current issues]

In sub-Saharan Africa, stroke is likely to present an increasingly important public health problem with a larger relative share of overall morbidity and mortality. Overall, sub-Saharan Health Care is characterized by a lack of human resources, lack of facilities for special investigations, and especially an absence of specific programs addressing the prevention of cardiovascular conditions. Current data on the epidemiology of stroke in sub-Saharan Africa, although sparse and fragmentary, indicate a comparatively high incidence of cerebral hemorrhage associated with high blood pressure, while ischemic stroke in black Africans still appears to be related primarily to small artery disease, HIV infection, and sickle cell disease. With urbanization, the role of large-vessel atherosclerosis is increasing. It is thus essential to coordinate government funding, health care professionals and development agencies to address this rising health problem. Access to health care needs to be better structured, and screening programs should be developed in order to identify and treat vascular risk factors. Improved training of health care professionals is also required in the areas of prevention, diagnosis and management of stroke. Implementation of best-practice recommendations for the management of stroke adapted to the specificities and resources of African countries would help rationalize the scarce resources currently available.

Guideline for the management of chronic obstructive pulmonary disease--2011 update

OBJECTIVE

To revise the South African Guideline for the Management of Chronic Obstructive Pulmonary Disease (COPD) based on emerging research that has informed updated recommendations.

KEY POINTS

(1) Smoking is the major cause of COPD, but exposure to biomass fuels and tuberculosis are important additional factors. (2) Spirometry is essential for the diagnosis and staging of COPD. (3) COPD is either undiagnosed or diagnosed too late, so limiting the benefit of therapeutic interventions; performing spirometry in at-risk individuals will help to establish an early diagnosis. (4) Oral corticosteroids are no longer recommended for maintenance treatment of COPD. (5) A therapeutic trial of oral corticosteroids to distinguish corticosteroid responders from non-responders is no longer recommended. (6) Primary and secondary prevention are the most cost-effective strategies in COPD. Smoking cessation as well as avoidance of other forms of pollution can prevent disease in susceptible individuals and ameliorate progression. Bronchodilators are the mainstay of pharmacotherapy, relieving dyspnoea and improving quality of life. (7) Inhaled corticosteroids are recommended in patients with frequent exacerbations and have a synergistic effect with bronchodilators in improving lung function, quality of life and exacerbation frequency. (8) Acute exacerbations of COPD significantly affect morbidity, health care units and mortality. (9) Antibiotics are only indicated for purulent exacerbations of chronic bronchitis. (10) COPD patients should be encouraged to engage in an active lifestyle and participate in rehabilitation programmes.

OPTIONS

Treatment recommendations are based on the following: annual updates of the Global Obstructive Lung Disease (GOLD), initiative, that provide an evidence-based comprehensive review of management; independent evaluation of the level of evidence in support of some of the new treatment trends; and consideration of factors that influence COPD management in South Africa, including lung co-morbidity and drug availability and cost.

OUTCOME

Holistic management utilising pharmacological and nonpharmacological options are put in perspective.

EVIDENCE

Working groups of clinicians and clinical researchers following detailed literature review, particularly of studies performed in South Africa, and the GOLD guidelines. BENEFITS, HARMS AND COSTS. The guideline pays particular attention to cost-effectiveness in South Africa, and promotes the initial use of less costly options. It promotes smoking cessation and selection of treatment based on objective evidence of benefit. It also rejects a nihilistic or punitive approach, even in those who are unable to break the smoking addiction.

RECOMMENDATIONS

These include primary and secondary prevention; early diagnosis, staging of severity, use of bronchodilators and other forms of treatment, rehabilitation, and treatment of complications. Advice is provided on the management of acute exacerbations and the approach to air travel, prescribing long-term oxygen and lung surgery including lung volume reduction surgery.

VALIDATION

The COPD Working Group comprised experienced pulmonologists representing all university departments in South Africa and some from private practice, and general practitioners. Most contributed to the development of the previous version of the South African guideline. GUIDELINE SPONSOR: The meeting of the Working Group of the South African Thoracic Society was sponsored by an unrestricted educational grant from Boehringer Ingelheim and Glaxo-Smith-Kline.

First Report of Aster Yellows Phytoplasma in Grapevines in South Africa

For many years phytoplasma diseases have caused serious losses in most of the major grape-growing regions of the world, except South Africa, where a mixed phytoplasma infection was first reported in 2006 (1). During the early growing season of 2006, symptoms consistent with phytoplasma disease were observed in vineyards in the Olifants River Valley. Symptoms included yellowing of leaves, incomplete lignification of shoots, shortening of internodes, and the abortion of growth tips and immature bunches. Symptomatic shoots and leaves from grapevine cultivars (Merlot, Shiraz, Cabernet Sauvignon, Ruby Cabernet, Pinotage, Corinth, Chardonnay, Columbar, Chenin blanc, Sauvignon blanc, Sultana, and Regal) were collected during the early growing season (November) of 2006, 2007, and 2008. Total DNA was extracted from 32 of these samples (from single plants in the same vineyards over the 3 years) with the Invisorb Spin Plant Mini Kit (Invitek, Berlin, Germany) and tested by nested PCR using two universal primer pairs, P1/P7 and R16F2n/R16R2 (3). The first round of PCR of the 2006 samples yielded 1.8-kb fragments for 17 of the samples, while the nested PCR yielded an additional seven positive samples, confirming the necessity of nested PCR for reliable diagnosis. A similar trend was observed in the 2007 and 2008 PCR test results. All asymptomatic plants, which were included as negative controls, and water controls were negative by nested PCR. Twenty-four 1,245-bp amplicons, generated by nested PCR, were excised from gels, purified with a NucleoSpin Extract II Kit (Macherey-Nagel, Düren, Germany) and directly sequenced. Sequence data was compiled with the BioEdit Version 7.0.4.1 sequence alignment editor software (2), aligned using ClustalW Version 1.4 (4), and a consensus sequence was generated (GenBank Accession No. GQ365729). A BLAST search of the NCBI GenBank database using the individual sequences revealed high sequence identities (≥99%) with the aster yellows phytoplasma group (16SrI) and specifically with the subgroup 16SrI-B. In a comparison of the sequences of the 1.2-kb PCR fragments of 24 local samples with each other, sequence identities of ~99% were observed. These results clearly illustrate that all vines screened were infected with the same phytoplasma. Single nucleotide differences observed between different isolates may indicate the presence of closely related sequence variants of this phytoplasma. Aster yellows occurs worldwide and has been reported to infect grapevine–South Africa can now be added to this list. During the three seasons of our study, the area in which symptomatic vineyards were observed increased significantly, indicating spread by a biological vector. Moreover, infected vineyards were noticed in two other South African grape-growing regions. In contrast to the previous report, which reported a mixed infection of phytoplasmas of groups 16SrXII-A and 16SrII-B (1), PCR screening and sequencing of more than 40 individual samples from these areas confirmed these all to be infected with aster yellows phytoplasma only. To our knowledge, this is the first report of the detection and identification of an aster yellows phytoplasma causing grapevine yellows disease in South Africa.

References: (1) S. Botti and A. Bertaccini. Plant Dis. 90:1360, 2006. (2) T. A. Hall. Nucleic Acids. Symp. Ser. 41:95, 1999. (3) I.-M. Lee et al. Phytopathology 83:834, 1993. (4) J. D. Thompson et al. Nucleic Acids Res. 22:4673, 1994.

Integrated care improves risk-factor modification after stroke: initial results of the Integrated Care for the Reduction of Secondary Stroke model

OBJECTIVE

Despite evidence demonstrating that risk-factor management is effective in reducing recurrent cerebrovascular disease, there are very few structured care programmes for stroke survivors. The aim was to implement and evaluate an integrated care programme in stroke.

METHODS

186 patients with stroke were randomised to either the treatment (integrated care) or control (usual care) group and were followed up over 12 months. The Integrated Care for the Reduction of Secondary Stroke (ICARUSS) model of integrated care involved collaboration between a specialist stroke service, a hospital coordinator and a patient's general practitioner. The primary aim was to promote the management of vascular risk factors through ongoing patient contact and education.

RESULTS

In the 12 months poststroke, systolic blood pressure (sBP) decreased in the treatment group but increased in controls. The group difference was significant, and remained so when age, sex, disability and sBP at discharge were accounted for (p = 0.04). Treatment patients also exhibited better modification of body mass index (p = 0.007) and number of walks taken (p<0.001) than controls. Rankin scores indicated significantly reduced disability in treatment patients relative to controls in the year poststroke (p = 0.003).

CONCLUSIONS

Through an integrated system of education, advice and support to both patient and GP, the ICARUSS model was effective in modifying a variety of vascular risk factors and therefore should decrease the likelihood or recurrent stroke or vascular event.

Regenerate: assessing the feasibility of a strength-training program to enhance the physical and mental health of chronic post stroke patients with depression

OBJECTIVE

The Regenerate pilot study explored whether a 10-week, community-based progressive resistance training (PRT) program could reduce depressive symptoms in depressed chronic stroke survivors.

METHODS

Participants were screened for depressive status using the PHQ-9 and confirmed by psychiatric assessment. Eligible people (n = 45) were randomised to PRT or a waiting-list comparison group. The PRT program included two high intensity sessions/week for 10 weeks at a community-based gymnasium. Depressive status, physical and mental health and quality of life were measured at baseline, 10 weeks and 6 months. Muscle strength was assessed using 1 repetition maximum (1-RM) for upper and lower limbs.

RESULTS

The participants' median age was 69 years: 27 were male. The intervention group had lower depression scores than the comparison group at all time points. At 6-month follow-up, there was a trend for PRT participants to be more likely to be no longer depressed than the comparison group, but the difference was not significant after adjusting for baseline scores. There were modest improvements in health and wellbeing over time, but many scores were lower than reported in non-depressed people. Intervention participants demonstrated significant improvements in strength. Program adherence was good: on average 75% of the 10-week program was completed.

CONCLUSIONS

The intervention appeared to be feasible within a community-based setting. To optimize stroke recovery and improve the quality of life of stroke survivors, health professionals should continue to focus on helping survivors' mental health recovery as well their physical rehabilitation.

Emergency percutaneous tracheostomy

We present a case of acute upper airway obstruction secondary to angio-oedema. The patient underwent emergency percutaneous tracheotomy. Other options available for emergency surgical airway are discussed.

27BIRTH OF AFRICA'S FIRST NUCLEAR-TRANSFERRED ANIMAL PRODUCED WITH HANDMADE CLONING

Cloning technology has the potential to stimulate the development of the animal biotechnology industry in southern Africa, as well as provide conservationists with an additional tool to possibly assist with conserving critically endangered wildlife species sometime in the future. The aim of this study was to determine whether cloning could produce blastocysts and possibly live progeny in a field-type laboratory without micromanipulators and CO2 incubator. Approx. 1×1-cm ear skin notches were surgically removed from a physically immobilized 9-year-old Holstein cow, a former South African milk production record holder. The tissues were placed into physiological saline and transported to the laboratory at 4°C within 2h, cleaned with chlorohexidine gluconate and sliced finely in Minimal Essential Medium supplemented with 10% fetal calf serum. The resultant tissue explants were treated as previously described (Bartels et al., 2003 Theriogenology 59, 387) and actively growing fibroblast cultures were made available for the nuclear transfer process. Bovine oocytes from slaughterhouse-derived ovaries were collected and matured for 21h in modified TCM-199 medium supplemented with 15% cattle serum, 10IUmL−1 eCG and 15IUmL−1 hCG. Nuclear transfer was performed using the HMC technique (Vajta et al., 2003 Biol. Reprod. 68, 571–578). At 21h after the start of maturation, cumulus cells and zonae pellucidae were removed and oocytes were randomly bisected by hand. Cytoplasts were selected using Hoechst staining and a fluorescent microscope. After a two-step fusion, reconstructed embryos were activated with calcium ionophore and dimethylaminopurine. Culture was performed in SOFaaci medium supplemented with 5% cattle serum using WOWs (Vajta et al., Mol. Reprod. Dev. 50, 185–191). All incubations including culture of donor cells were performed in the submarine incubator system (SIS; Vajta et al., 1997 Theriogenology 48, 1379–1385). In two consecutive experiments, 6 blastocysts were produced from 52 reconstructed embryos. On Day 7, 5 blastocysts were selected for transfer into 3 previously synchronized recipients. All three recipients became pregnant, but two of the recipients aborted at six and seven months, respectively. Post-mortem examination on the first aborted fetus did not reveal any identifiable etiology, but coincided with 6 abortions from natural pregnancies during a heat wave, while the organism Brucella abortis was isolated from the second aborted fetus. The third pregnancy went to term, and a healthy calf, weighing 27kg, was delivered by Caesarean section. The three-month-old calf is being raised by a surrogate Jersey cow under standard dairy conditions and is expected to join the dairy in eighteen months’ time. The birth of ‘Futhi’, meaning ‘replicate’ in Zulu, is Africa’s first cloned animal and signifies an important milestone in the development of animal biotechnology in Africa.

Ischemic heart disease in black South African stroke patients

BACKGROUND AND PURPOSE

Stroke patients in western countries frequently have coronary artery disease (CAD). In black Africans, CAD has been reported as being rare in both stroke patients and the general population. In this study, an attempt has been made to determine the prevalence of CAD in a black South African stroke population.

METHODS

The prevalence of CAD was determined by indicators identified through a series of 5 observational studies in black patients diagnosed with stroke. CAD indicators included (1) bedside diagnosis in 741 patients; (2) resting ECG in 555 consecutively admitted patients; (3) a combination of clinical examination, cardiac ultrasound, radionuclide scintigraphy, and multigated blood pool studies in 102 consecutively admitted patients; (4) thallium scintigraphy in 60 patients; and (5) necropsy in 23 patients.

RESULTS

On bedside questioning, only 0.7% complained of previous angina. There was no history given of myocardial infarction (MI), but documentation of this was found in the clinical notes of 0.7% of the patients. In the resting ECG study, evidence of myocardial ischemia was present in 14.6% and MI in 2.1%. In the combined study, cardiac ischemia was documented on ECG in 12.7% of patients and evidence of previous MI in 5.8%. Cardiac scintigraphic studies revealed changes of myocardial ischemia in 31.7% and MI in 13.3% of the 60 patients studied. Four (17.4%) of 23 patients in the necropsy study had histological evidence of previous MI, and 50% of all patients had evidence of >50% atherosclerotic stenosis in 1, 2, or 3 coronary arteries.

CONCLUSIONS

The prevalence of CAD in black African stroke patients is significantly higher than has been documented in the general nonstroke black population as well as in stroke patients. Black stroke patients may have a risk for CAD similar to that of their white counterparts.

[Microinvasive ductal carcinoma of the breast. Role of axillary lymph node dissection]

The role of axillary lymph node dissection for microinvasive ductal carcinoma in situ of the breast was analyzed in a series of 60 consecutive cases. Forty-four cases were subclinical mammographically-detected carcinomas revealed by the clusters of microcalcifications. Although pathologists differ in their criteria for microinvasion, the maximal size considered in this retrospective study was 2 mm. Axillary lymph node involvement was found in 3 cases (i.e. 5%) which harbored poor histologic features: comedocarcinoma subtype, high nuclear grade, and size of the ductal carcinoma in situ greater than 3 cm, requiring total mastectomy. While there is no need for axillary dissection in women with pure ductal carcinoma in situ, the management is quite different in proven microinvasion. Owing to the weakness of prognostic information given by cellular, biochemical and molecular features, instead of lymph node status, axillary dissection is still recommended in microinvasive ductal carcinoma in situ.

Hyperhomocysteinaemia in black patients with cerebral thrombosis

Hyperhomocysteinemia is regarded as a risk factor for stroke but its pathogenetic role has not yet been established in Black patients. We studied 24 Black patients admitted with cerebral thrombosis, and compared them with age- and sex-matched apparently healthy controls from the same community. Total homocysteine (tHcy) (free homocysteine, protein-bound homocysteine, the disulfide homocystine and the mixed disulfide homocysteine-cysteine) concentration was 10.91 (4.95-23.05) mumol/l in the stroke patients and 8.73 (3.95-15.10) mumol/l in controls (p = 0.031). This difference could not be explained by differences in vitamin B12, vitamin B6 or folate status. A subgroup of nine stroke patients with hypercreatininaemia (> 90 mumol/l, 75% of control concentrations) had significantly higher plasma tHcy concentrations [median (range) 9.10 (5.40-15.10) mumol/l] compared with controls [8.65 (3.96-13.89) mumol/l] (p = 0.002). Plasma tHcy concentrations of stroke patients with normal serum creatinine concentrations were not significantly different to those of controls. Hyperhomocysteinemia in Black patients with stroke may be partially caused by renal insufficiency. Therefore, while hyperhomocysteinemia may increase the risk of stroke, it is unlikely to be a primary initiating factor.

SUNCT syndrome. Atypical temporal patterns

New clinical features of the SUNCT syndrome are described in a series of 3 men (mean age of 65 years, range 56 to 80). The mean age at the onset of symptoms was 55 years (range 39 to 77). Although in all patients the great majority of attacks were typical, on a few occasions unusual features of the painful attacks were either reported or witnessed by the investigators. We have classified these clinical phenomena as (1) low-grade background pain or discomfort, and (2) relatively long-lasting attacks. Neither neurological examination nor neuroimaging studies revealed structural lesions as responsible for the atypical features. The fact that these atypical attacks occurred in the usual symptomatic area and were accompanied by the usual ipsilateral autonomic signs, suggests that they are an integral part of the clinical picture of SUNCT. The possibility that another, concurrent headache was responsible for the unusual attacks is considered unlikely. These clinical phenomena should, accordingly, provisionally be considered as additional but rare clinical features of the SUNCT syndrome.

Cervical intraspinal lipoma in a pregnant patient

Tetraparesis developing in a female, during pregnancy, was found to be due to an intradural cervical lipoma, associated with a subcutaneous lipoma at the same level in the midline posteriorly. Sub-total removal produced a return to near normal function with the patient being fully ambulant 7 months later.

Flunarizine--effective add-on therapy in reading epilepsy

Since it was first described in 1956, reading epilepsy, an uncommon disorder, has engendered great interest among neurologists, the reason being that it is probably one of the most complex of the sensory-evoked reflex epilepsies and one in which the mechanism of seizure production is as yet unresolved. Unfortunately, it often defies the standard medications useful in the treatment of other forms of epilepsy. A patient with typical reading epilepsy, preceded by jaw-jerking, is described in this report. An additional feature of this case is the presence of a stutter from early childhood. Therapy with phenytoin, carbamazepine and sodium valproate failed to provide satisfactory control. Flunarizine, as add-on therapy to sodium valproate, produced an excellent therapeutic response.

The MEDUNSA Stroke Data Bank. An analysis of 304 patients seen between 1986 and 1987

Stroke is a major cause of mortality and morbidity in black Africans. The MEDUNSA Stroke Data Bank (MSDB) was established in 1984. Its goal is to gather data on all aspects of cerebrovascular disease in South African blacks, and it is supported by modern investigative techniques such as computed tomography (utilised in 82.2% of cases). The majority of the patients (71.2%) had cerebral infarction. Certain features, such as the importance of hypertension and increasing age as risk factors, were found to be similar to Western stroke populations; also, probable or definite cardiac source for cerebral embolism was present in 46% of the patients. In contrast, however, other features, such as transient ischaemic attacks, peripheral vascular disease, coronary artery disease and lacunar strokes, occurred far less frequently than is reported in Western patients. It is hoped that the MSDB will lead to a better understanding of cerebrovascular disease in blacks and possibly to in-depth comparative studies of the ubiquitous problem of atherosclerosis.

Human T-lymphotropic virus type I-associated myelopathy. A case report

Tropical spastic paraparesis (TSP) has been reported from various parts of the world for several decades. Recently reports have emerged from Japan and also countries in tropical zones associating endemic TSP with abnormally high titres of antibodies to human T-lymphotropic virus type I (HTLV-I). Data indicate that this lymphotropic retrovirus is neuropathogenic, either by direct invasion or via immunopathological mechanisms. A South African man is described who met the diagnostic criteria of TSP. Both serum and cerebrospinal fluid were antibody-positive for HTLV-I. It is possible that HTLV-I infection may be implicated in the 'myelopathies of undetermined cause' that form a substantial subgroup of spinal cord disease occurring in black South Africans.

Neurocysticercosis in 578 black epileptic patients

In a study of 578 epileptic patients at the Ga-Rankuwa Hospital, 281 had abnormal computed tomography (CT) of the brain (48.6%), and in 162 (average age 32 years) there was evidence of cysticercosis (57.6%). In 68 of the infected patients (41.9%) active cysts were seen on CT. Neurocysticercosis, either active or inactive, was thus implicated in 28% of this group of epileptic patients, which emphasises the importance of this disease in the causation of epilepsy in the black population of South Africa.

Genetic linkage between Huntington disease and the D4S10 locus in South African families: further evidence against non-allelic heterogeneity

A study of genetic linkage between Huntington disease (HD) and the D4S10 locus (G8) has been undertaken in 10 South African (SA) families originating from the black, white and mixed acestry population groups. Allele frequencies at the D4S10 locus have been established in the non-Caucasoid population groups. There are significant differences in the allele frequencies at the D4S10 locus between the various SA populations. Clearly, information about population-specific frequencies for all polymorphisms is essential prior to the implementation of predictive testing in different population groups. Linkage has been demonstrated within this mixed group of HD families in SA using the HindIII, EcoRI and MspI polymorphisms, detected by G8. A maximum lod score of 8.14 at a recombination fraction of 0.00 (confidence limit 0-0.058) has been calculated using a combined haplotype of the HindIII and MspI polymorphisms. Taking into account the diverse ethnic backgrounds of the different SA population groups in this investigation, the data obtained from the study provide further evidence that there is probably only a single HD locus.

Hemicrania continua in a black patient--the importance of the non-continuous stage

A 52-year-old black female for 19 years had severe intermittent unilateral headaches that demonstrated the "clustering" phenomenon. She was initially diagnosed as having episodic cluster headache. Response to lithium carbonate, ergotamine and courses of corticosteroids was, however, only partial. In December 1989 the headache pattern changed and she developed severe unilateral hemicranial headache that was continuous and non-remitting. This responded immediately and persistently to oral indomethacin. A diagnosis of hemicrania continua (HC) was made. The initial intermittent headache syndrome appears to have been the pre-continuous stage of hemicrania continua, and not episodic cluster headache as previously supposed. The pre-continuous phase of hemicrania continua may thus masquerade as episodic cluster headache by reason of its intermittency and "clustering". In this case, the intermittent stage was protracted. This stage may, conceivably, even be a permanent one. To our knowledge, this is the first report of hemicrania continua in a black African.

Glue sniffing: A description of social, psychological and neuropsychological factors in a group of South African ‘street children’

Twenty-two black South African boys who had histories of prolonged glue sniffing, but who were currently not abusing solvents, were evaluated by means of neuropsychological and neurological procedures. On the neuropsychological procedures the group demonstrated multiple deficits which included visual-spatial difficulties, visual scanning problems, language deficiencies, motor incoordination, memory deficits, and attention and concentration problems. The neurological examination showed that two boys had cerebellar signs. Nine of the recorded electroencephalograms were found to be abnormal. The backgrounds and personality profiles of the group together with the circumstances which led to their glue-sniffing activities are discussed.

Cysticercal meningitis--a pernicious form of neurocysticercosis which responds poorly to praziquantel

Chronic cysticercal meningitis was diagnosed in 6 of 260 cases of neurocysticercosis. Clinical features usually associated with meningitis, such as fever, cranial nerve palsies and nuchal rigidity, were absent and the diagnosis was reached because of persistently abnormal cerebrospinal fluid (CSF) associated with active neurocysticercosis on computed tomography. Other causes of chronic meningitis were excluded. Hydrocephalus, either obstructive or communicating, was present in all 6 patients. The results of medical treatment with praziquantel were poor and there was no improvement either clinically or in the CSF. Severe clinical sequelae, such as dementia, blindness and gait ataxia, were common despite protracted medical treatment and ventriculoperitoneal shunting.

Schistosomiasis of the spinal cord--underdiagnosed in South Africa?

Schistosomiasis is endemic in many areas of South Africa, particularly the northern and eastern Transvaal. At Ga-Rankuwa Hospital in the northern Transvaal, 30 km north-west of Pretoria, spinal cord disease is common. In a substantial proportion of these cases no obvious cause for the condition can be found. In an attempt to draw attention to schistosomiasis as a possibly underdiagnosed cause of spinal cord disease, 3 cases of schistosomiasis of the spinal cord seen over a period of 3 years are reported. These 3 patients had histological evidence of spinal schistosomiasis. Because myelography of the spinal cord is often non-contributory in schistosomal involvement, it is suggested that patients with 'myelopathy of unknown origin' who come from an endemic area be given a therapeutic trial of praziquantel, especially if the serological findings are positive for schistosomiasis and the lower cord is involved.

Use of indium-111-labelled platelets in black stroke patients. A pilot study

Human blood platelets labelled with indium-111 oxine have been shown to accumulate on damaged vascular surfaces and abnormal platelet deposition has been demonstrated in the carotid arteries of white stroke patients. Gamma scintigraphy of the carotid and cerebral arteries of 5 black stroke patients and 5 age- and sex-matched controls using 111In-labelled platelets showed no abnormal accumulation indicative of carotid artery disease.