Breast Cancer Stage at Diagnosis in a Nigerian Hospital: Trend over a Decade

BACKGROUND

Breast cancer outcomes are poor in Nigeria, partly due to late-stage diagnosis. To assess the impact of past and present interventions, a review of an institutional data base was performed to determine the trend with respect to stage at diagnosis over a decade.

METHODS

A retrospective analysis of an institutional data base was performed over a decade. The review period was divided into segments (2013-2015, 2016-2018 and 2019-2022). The latter period (2019-2022), corresponds to a time of more intense community interventions aimed at promoting early diagnosis and treatment around the locality of the teaching hospital. The stage at diagnosis within these periods were compared. The relationship between stage and sociodemographic variables (age, religion, marital status, menopausal status, and level of education) was assessed.

RESULTS

There were 910 patients, 144 within the first period (2013-2015), 318 in the second (2016-2018) and 454 in the third period (2019-2022). The majority presented with stage 3 disease (73.8%). There was a significant decline in the proportion of metastatic cases and a concomitant increase in early cases in the latter part of the review. The proportion of metastatic cases reduced from 23.6% (2013-2015), to 15.7% (2016-2018) and 9.3% (2019-2022) (p=0.001). Level of education was significantly associated with stage (p=0.001).

CONCLUSION

This study shows a trend towards downstaging of breast cancer in our locality. This trend corresponds to the period of more intense community interventions, justifying the need to further interrogate the direct impact of each of the interventions. This will provide a firm basis for sustaining or improving on current efforts to achieve more robust gains.

A Prospective, Observational Cost Comparison of Laparoscopic and Open Appendicectomy in Three Tertiary Hospitals in Nigeria

BACKGROUND

The clinical benefits of laparoscopic appendicectomy are well recognized over open appendicectomy. However, laparoscopic procedures are not frequently conducted in many low-and middle-income countries (LMICs) for several reasons, including perceived higher costs. The aim of this study was to assess the feasibility and cost of laparoscopic appendicectomy compared to open appendicectomy in Nigeria.

METHODS

A multicenter, prospective, cohort study among patients undergoing appendicectomy was conducted at three tertiary hospitals in Nigeria. Data were collected from October 2020 to February 2022 and analyses compared the average healthcare costs at 30 days after surgery. Quantile regression was conducted to identify variables that had an impact on the costs, reported in Nigerian Naira (Naira) and US dollars ($), with standard deviations (SD).

FINDINGS

This study included 105 patients, of which 39 had laparoscopic appendicectomy and 66 had open appendicectomy. The average healthcare cost of laparoscopic appendicectomy (147,562 Naira (SD: 97,130) or $355 (SD: 234)) was higher than open appendicectomy (113,556 Naira (SD: 88,559) or $273 (SD: 213)). The average time for return to work was shorter with laparoscopic than open appendicectomy (mean: 8 days vs. 14 days). At the average daily income of $5.06, laparoscopic appendicectomy was associated with 9778 Naira or $24 cost savings in return to work. Further, 5.1% of laparoscopic appendicectomy patients had surgical site infections compared to 22.7% for open appendicectomy. Regression analysis results showed that laparoscopic appendicectomy was associated with $14 higher costs than open appendicectomy, albeit non-significant (p = 0.53).

INTERPRETATION

Despite selection bias in this real-world study, laparoscopic appendicectomy was associated with a slightly higher overall cost, a lower societal cost, a lower infection rate, and a faster return to work, compared to open appendicectomy. It is technically and financially feasible, and its provision in Nigeria should be expanded.

Reducing the environmental impact of surgery on a global scale: systematic review and co-prioritization with healthcare workers in 132 countries

BACKGROUND

Healthcare cannot achieve net-zero carbon without addressing operating theatres. The aim of this study was to prioritize feasible interventions to reduce the environmental impact of operating theatres.

METHODS

This study adopted a four-phase Delphi consensus co-prioritization methodology. In phase 1, a systematic review of published interventions and global consultation of perioperative healthcare professionals were used to longlist interventions. In phase 2, iterative thematic analysis consolidated comparable interventions into a shortlist. In phase 3, the shortlist was co-prioritized based on patient and clinician views on acceptability, feasibility, and safety. In phase 4, ranked lists of interventions were presented by their relevance to high-income countries and low-middle-income countries.

RESULTS

In phase 1, 43 interventions were identified, which had low uptake in practice according to 3042 professionals globally. In phase 2, a shortlist of 15 intervention domains was generated. In phase 3, interventions were deemed acceptable for more than 90 per cent of patients except for reducing general anaesthesia (84 per cent) and re-sterilization of 'single-use' consumables (86 per cent). In phase 4, the top three shortlisted interventions for high-income countries were: introducing recycling; reducing use of anaesthetic gases; and appropriate clinical waste processing. In phase 4, the top three shortlisted interventions for low-middle-income countries were: introducing reusable surgical devices; reducing use of consumables; and reducing the use of general anaesthesia.

CONCLUSION

This is a step toward environmentally sustainable operating environments with actionable interventions applicable to both high- and low-middle-income countries.

A service evaluation of joint working across sectors to promote self-administration of subcutaneous systemic anti-cancer therapy in breast cancer patients

Introduction

Trastuzumab(T) is a humanized monoclonal antibody used in the treatment of HER2-positive breast cancer and is available as a subcutaneous(sc) formulation thereby allowing short and convenient administration. A lack of trained nurses to administer T at home and/or train patients at home to self-administer, together with challenges in maintaining cold-chain delivery have impeded uptake of home administration.1,2 In order to support patients’ ability to self-administer T at home, we have implemented an educational programme that includes nurse-led training, education material, support apps and follow-up telephone clinics. Home delivery of pre-filled syringes was enabled in collaboration with commercial providers for aseptics and logistic.

Aim

The aim of this service evaluation was to evaluate the utility of this programme from the patients’ perspective and to assess patient satisfaction and impact on quality of life (QOL).

Methods

A previously validated Self-Injection Assessment Questionnaire (SIAQ)3 was modified to assess patient satisfaction, perceptions and impact of the programme. Patients who had agreed to enrol on the ‘self-administration’ scheme, were asked to complete the questionnaire at baseline, at the third training session and at the second self-administered dose. Approval from a Research Ethics Committee is not required for this service evaluation.

Results

All 14 patients offered the questionnaire responded to all questions. The median age was 58 years old (age range 43-76), 11 patients were Caucasian, 2 were Asian and one was African/Caribbean. The average distance from their home address to hospital was 10.1 miles (range 4-19). Following completion of the one-to-one nurse training there was an improvement in patient confidence to self-administer sc. T. No differences in ‘feeling in control of their treatment’ or ‘satisfaction of attending hospital appointments’ were noted. Of the 11 patients who reached the self-administration stage, 10 reported that they felt ‘very confident’ and 8 reported that it was ‘very easy’ to give themselves the injection. All patients rated themselves ‘very satisfied’ with self-administration and reported that the nurse training programme helped them to be more confident. 10 patients reported that the App and written information was useful as well as the pre- and post- administration telephone clinics. All patients reported that the self-administration programme had a positive impact on their QOL by reducing the number of hospital visits. In the first 4 months of self-administration each patient reduced their hospital attendance by an average of 8 appointments (median=8) equating to 10 hours of time that would have been spent at hospital.

Discussion/Conclusion

The subcutaneous T self-administration programme was well received by patients. The nurse training sessions and supportive materials enabled patients to feel more confident about self-administration with no reported incidents or adverse events. This led to fewer hospital visits and improved QOL. This programme was critically dependent on the services of a commercial compounder and homecare provider, emphasizing the importance of joint working between the NHS and commercial sector. Evaluation of this programme will continue and will include other agents, including Phesgo® (sc trastuzumab and pertuzumab) which have more patients and will improve the reliability of the results.

References

1. Tjalma, W., Huizing, M., Papadimitriou, K. The smooth and bumpy road of trastuzumab administration: from intravenous (IV) in a hospital to subcutaneous (SC) at home. Facts Views Vis Obgyn, 2017;9(1):51-55.

2. Grady, PA, Gough, LL. Self-management: a comprehensive approach to management of chronic conditions. American Journal of Public Health 2014; 104(8):e25-31. doi:10.2105/AJPH.2014.302041

3. Keininger D, Coteur G. Assessment of self-injection experience in patients with rheumatoid arthritis: psychometric validation of the Self-Injection Assessment Questionnaire (SIAQ). Health Qual Life Outcomes. 2011;9:2. doi:10.1186/1477-7525-9-2

Association of lipid profile biomarkers with breast cancer by molecular subtype: analysis of the MEND study

There is conflicting evidence on the role of lipid biomarkers in breast cancer (BC), and no study to our knowledge has examined this association among African women. We estimated odds ratios (ORs) and 95% confidence intervals (95% CI) for the association of lipid biomarkers-total cholesterol, high-density lipoprotein (HDL), low-density lipoprotein (LDL), and triglycerides-with odds of BC overall and by subtype (Luminal A, Luminal B, HER2-enriched and triple-negative or TNBC) for 296 newly diagnosed BC cases and 116 healthy controls in Nigeria. Each unit standard deviation (SD) increase in triglycerides was associated with 39% increased odds of BC in fully adjusted models (aOR: 1.39; 95% CI: 1.03, 1.86). Among post-menopausal women, higher total cholesterol (aOR: 1.65; 95% CI: 1.06, 2.57), LDL cholesterol (aOR: 1.59; 95% CI: 1.04, 2.41), and triglycerides (aOR: 1.91; 95% CI: 1.21, 3.01) were associated with increased odds of BC. Additionally, each unit SD increase in LDL was associated with 64% increased odds of Luminal B BC (aOR 1.64; 95% CI: 1.06, 2.55). Clinically low HDL was associated with 2.7 times increased odds of TNBC (aOR 2.67; 95% CI: 1.10, 6.49). Among post-menopausal women, higher LDL cholesterol and triglycerides were significantly associated with increased odds of Luminal B BC and HER2 BC, respectively. In conclusion, low HDL and high LDL are associated with increased odds of TN and Luminal B BC, respectively, among African women. Future prospective studies can definitively characterize this association and inform clinical approaches targeting HDL as a BC prevention strategy.

Use of energy device in general surgical operations: impact on peri-operative outcomes

BACKGROUND

The introduction of energy devices has significantly expanded the scope of surgical expedition. The LigaSure™ vessel sealing system is a bipolar electrosurgical device, recently introduced to our practice. Its impact on peri-operative outcomes in a variety of major operations was evaluated in this study.

METHODS

A retrospective review of operations performed following the adoption of the LigaSure™ vessel sealing device was carried out. Five categories of operations were evaluated (Thyroidectomies, Gastrectomies, Colectomies, Pancreaticoduodenectomies, and Anterior/Abdomino-perineal resection [A/APR of the rectum). Peri-operative outcomes (duration of operation, intra-operative blood loss, blood transfusion rates) were compared with a cohort of similar operations performed using conventional techniques. Data analysis and comparisons were done on a subgroup basis.

RESULTS

A total of 117 operations were performed using the LigaSure™ device with thyroidectomies being the most common (66/117-56.4%). Compared to cases done using conventional techniques of suture and knot with electrocautery (120 cases), the use of LigaSure™ was associated with a significant reduction in operation time in all categories of operations. Intraoperative blood loss was also lower in all categories of cases, but this was only statistically significant following A/APR and Thyroidectomies. Generally, there was a trend towards a reduction in blood transfusion rates.

CONCLUSIONS

The use of energy devices for surgical operations is feasible in a resource-limited setting. It has the potential of improving outcomes.

Metabolic Syndrome and Risk of Breast Cancer by Molecular Subtype: Analysis of the MEND Study

Metabolic syndrome is a cluster of biological irregularities that is a known risk factor for cardiovascular disease, stroke, and diabetes. In a case-control study of 555 West African women, we observed that metabolic syndrome was strongly associated with breast cancer and the aggressive triple-negative molecular subtype, highlighting a need for clinical and lifestyle interventions targeting metabolic syndrome to reduce breast cancer risk in this population.

Association of body composition with odds of breast cancer by molecular subtype: analysis of the Mechanisms for Established and Novel Risk Factors for Breast Cancer in Nigerian Women (MEND) study

BACKGROUND

The association between obesity and breast cancer (BC) has been extensively studied among US, European and Asian study populations, with often conflicting evidence. However, despite the increasing prevalence of obesity and associated conditions in Africa, the continent with the highest age-standardized BC mortality rate globally, few studies have evaluated this association, and none has examined in relation to molecular subtypes among African women. The current analysis examines the association between body composition, defined by body mass index (BMI), height, and weight, and BC by molecular subtype among African women.

METHODS

We estimated odds ratios (ORs) and 95% confidence intervals (95% CI) for the association between measures of body composition and BC and molecular subtypes among 419 histologically confirmed cases of BC and 286 healthy controls from the Mechanisms for Established and Novel Risk Factors for Breast Cancer in Women of Nigerian Descent (MEND) case-control study.

RESULTS

Higher BMI (aOR: 0.79; 95% CI: 0.67, 0.95) and weight (aOR: 0.83; 95% CI: 0.69, 0.98) were associated with reduced odds of BC in adjusted models, while height was associated with non-statistically significant increased odds of BC (aOR: 1.07, 95% CI: 0.90, 1.28). In pre/peri-menopausal, but not post-menopausal women, both higher BMI and weight were significantly associated with reduced odds of BC. Further, higher BMI was associated with reduced odds of Luminal A, Luminal B, and HER2-enriched BC among pre/peri-menopausal women, and reduced odds of triple-negative BC among post-menopausal women.

CONCLUSIONS

Higher BMI and weight were associated with reduced odds of BC overall and by molecular subtype among West African women. Larger studies of women of African descent are needed to definitively characterize these associations and inform cancer prevention strategies.

Association of high-sensitivity C-reactive protein and odds of breast cancer by molecular subtype: analysis of the MEND study

Breast cancer (BC) in Nigeria is characterized by disproportionately aggressive molecular subtypes. C-reactive protein (CRP) is associated with risk and aggressiveness for several types of cancer. We examined the association of high-sensitivity CRP (hsCRP) with odds of BC by molecular subtype among Nigerian women. Among 296 newly diagnosed BC cases and 259 healthy controls, multivariable logistic regression models were used to estimate adjusted odds ratios (aOR) and 95% confidence intervals (CI) for the association between hsCRP and odds of BC overall and by molecular subtype (luminal A, luminal B, HER2-enriched and triple-negative or TNBC). High hsCRP (> 3 mg/L) was observed in 57% of cases and 31% of controls and was associated with 4 times the odds of BC (aOR: 4.43; 95% CI: 2.56, 7.66) after adjusting for socio-demographic, reproductive, and clinical variables. This association persisted regardless of menopausal status and body mass index (BMI) category. High hsCRP was associated with increased odds of TNBC (aOR: 3.32; 95% CI: 1.07, 10.35), luminal A BC (aOR: 4.03; 95% CI: 1.29, 12.64), and HER2-enriched BC (aOR: 6.27; 95% CI: 1.69, 23.25). Future studies are necessary in this population to further evaluate a potential role for CRP as a predictive biomarker for BC.

Contemporary management of breast cancer in Nigeria: Insights from an institutional database

High-quality data are needed to guide interventions aimed at improving breast cancer outcomes in sub-Saharan Africa. We present data from an institutional breast cancer database to create a framework for cancer policy and development in Nigeria. An institutional database was queried for consecutive patients diagnosed with breast cancer between January 2010 and December 2018. Sociodemographic, diagnostic, histopathologic, treatment and outcome variables were analyzed. Of 607 patients, there were 597 females with a mean age of 49.8 ± 12.2 years. Most patients presented with a palpable mass (97%) and advanced disease (80.2% ≥ Stage III). Immunohistochemistry was performed on 21.6% (131/607) of specimens. Forty percent were estrogen receptor positive, 32.8% were positive for HER-2 and 43.5% were triple negative. Surgery was performed on 49.9% (303/607) of patients, while 72% received chemotherapy and 7.9% had radiotherapy. At a median follow-up period of 20.5 months, the overall survival was 43.6% (95% CI -37.7 to 49.5). Among patients with resectable disease, 18.8% (57/303) experienced a recurrence. Survival was significantly better for early-stage disease (I and II) compared to late-stage disease (III or IV) (78.6% vs 33.3%, P < .001). Receipt of adjuvant radiotherapy after systemic chemotherapy was associated with improved survival in patients with locally advanced disease (68.5%, CI -46.3 to 86 vs 51%, CI 38.6 to 61.9, P < .001). This large cohort highlights the dual burden of advanced disease and inadequate access to comprehensive breast cancer care in Nigeria. There is a significant potential for improving outcomes by promoting early diagnosis and facilitating access to multimodality treatment.

Global variation in postoperative mortality and complications after cancer surgery: a multicentre, prospective cohort study in 82 countries

BACKGROUND

80% of individuals with cancer will require a surgical procedure, yet little comparative data exist on early outcomes in low-income and middle-income countries (LMICs). We compared postoperative outcomes in breast, colorectal, and gastric cancer surgery in hospitals worldwide, focusing on the effect of disease stage and complications on postoperative mortality.

METHODS

This was a multicentre, international prospective cohort study of consecutive adult patients undergoing surgery for primary breast, colorectal, or gastric cancer requiring a skin incision done under general or neuraxial anaesthesia. The primary outcome was death or major complication within 30 days of surgery. Multilevel logistic regression determined relationships within three-level nested models of patients within hospitals and countries. Hospital-level infrastructure effects were explored with three-way mediation analyses. This study was registered with ClinicalTrials.gov, NCT03471494.

FINDINGS

Between April 1, 2018, and Jan 31, 2019, we enrolled 15 958 patients from 428 hospitals in 82 countries (high income 9106 patients, 31 countries; upper-middle income 2721 patients, 23 countries; or lower-middle income 4131 patients, 28 countries). Patients in LMICs presented with more advanced disease compared with patients in high-income countries. 30-day mortality was higher for gastric cancer in low-income or lower-middle-income countries (adjusted odds ratio 3·72, 95% CI 1·70-8·16) and for colorectal cancer in low-income or lower-middle-income countries (4·59, 2·39-8·80) and upper-middle-income countries (2·06, 1·11-3·83). No difference in 30-day mortality was seen in breast cancer. The proportion of patients who died after a major complication was greatest in low-income or lower-middle-income countries (6·15, 3·26-11·59) and upper-middle-income countries (3·89, 2·08-7·29). Postoperative death after complications was partly explained by patient factors (60%) and partly by hospital or country (40%). The absence of consistently available postoperative care facilities was associated with seven to 10 more deaths per 100 major complications in LMICs. Cancer stage alone explained little of the early variation in mortality or postoperative complications.

INTERPRETATION

Higher levels of mortality after cancer surgery in LMICs was not fully explained by later presentation of disease. The capacity to rescue patients from surgical complications is a tangible opportunity for meaningful intervention. Early death after cancer surgery might be reduced by policies focusing on strengthening perioperative care systems to detect and intervene in common complications.

FUNDING

National Institute for Health Research Global Health Research Unit.

Geospatial access predicts cancer stage at presentation and outcomes for patients with breast cancer in southwest Nigeria: A population-based study

BACKGROUND

The majority of women in Nigeria present with advanced-stage breast cancer. To address the role of geospatial access, we constructed a geographic information-system-based model to evaluate the relationship between modeled travel time, stage at presentation, and overall survival among patients with breast cancer in Nigeria.

METHODS

Consecutive patients were identified from a single-institution, prospective breast cancer database (May 2009-January 2019). Patients were geographically located, and travel time to the hospital was generated using a cost-distance model that utilized open-source data. The relationships between travel time, stage at presentation, and overall survival were evaluated with logistic regression and survival analyses. Models were adjusted for age, level of education, and socioeconomic status.

RESULTS

From 635 patients, 609 were successfully geographically located. The median age of the cohort was 49 years (interquartile range [IQR], 40-58 years); 84% presented with ≥stage III disease. Overall, 46.5% underwent surgery; 70.8% received systemic chemotherapy. The median estimated travel time for the cohort was 45 minutes (IQR, 7.9-79.3 minutes). Patients in the highest travel-time quintile had a 2.8-fold increase in the odds of presenting with stage III or IV disease relative to patients in the lowest travel-time quintile (P = .006). Travel time ≥30 minutes was associated with an increased risk of death (HR, 1.65; P = .004).

CONCLUSIONS

Geospatial access to a tertiary care facility is independently associated with stage at presentation and overall survival among patients with breast cancer in Nigeria. Addressing disparities in access will be essential to ensure the development of an equitable health policy.

Collaborative Molecular Epidemiology Study of Metabolic Dysregulation, DNA Methylation, and Breast Cancer Risk Among Nigerian Women: MEND Study Objectives and Design

PURPOSE

To elucidate the role of metabolic dysregulation and associated DNA methylation changes on breast cancer risk and aggressive subtypes among Nigerian women. We describe the design and methods of a collaborative molecular epidemiology study of breast cancer in Nigerian hospitals.

METHODS

The Mechanisms for Novel and Established Risk Factors for Breast Cancer in Women of Nigerian Descent (MEND) study was designed as a matched case-control study of 350 patients, age 18 to 75 years, with newly diagnosed, treatment-naïve breast cancer and 350 age-matched healthy controls from surrounding geographic areas. Patients with breast cancer seen for initial diagnosis at four large tertiary hospitals in southwest Nigeria and one affiliated private hospital were recruited. Healthy female controls were selected from a cohort of 4,000 healthy women recruited as part of the Human Heredity and Health (H3) in Africa Chronic Kidney Disease Case-Control Study in Nigeria. Tumor and adjacent normal tissue, and blood and saliva samples were collected for molecular and epigenetic assays.

RESULTS

Although recruitment is ongoing, a total of 416 patients have been recruited to date, with tumor and blood samples obtained from at least 310 patients. Data on age-matched (± 6 months) controls have also been obtained and harmonized. Lipid assays for 350 pathologically verified cases and 350 age-matched controls is underway, and pathologic characterization of tumors (including immunohistochemistry for subtyping) is ongoing. Data on DNA methylation for tumors and adjacent normal tissue are expected by the end of the study period.

CONCLUSION

The MEND study will provide a unique, high-quality source of data to evaluate the contribution of metabolic dysregulation such as obesity, diabetes, hypertension, and metabolic syndrome to the biology of breast cancer among Nigerian women and foster collaborative studies relevant for women of African descent globally.

Safety and feasibility of early postmastectomy discharge and home drain care in a low resource setting

BACKGROUND

Early postmastectomy discharge with a drain in place is standard practice in most developed countries. Its feasibility has not been evaluated in low resource settings like Nigeria.

METHODS

Consenting patients undergoing mastectomy were discharged on the third postoperative day and assessed as outpatients for wound complications as well as their experience at home. Wound outcomes were compared with patients who had traditional long stay.

RESULTS

Forty-five of the 58 patients who had a mastectomy during the study period participated in the early discharge program (77.6%). Of these, four patients (8.9%) had drain malfunction, seroma occurred in eight patients (17.8%), eight patients (17.8%) had wound infection, and six patients (13.3%) had flap necrosis. There was no readmission. Compared with long stay patients, postoperative stay was significantly shorter (3 vs 11 days; P < 0.01) with significant cost savings, while complication rates were not statistically different. All the patients in the early discharge group were confident operating their drains and preferred early discharge. Being around relatives, reduced cost, and fear of the hospital environment were common reasons cited for their preference.

CONCLUSION

Our results support the implementation of an early postmastectomy discharge program in a low resource setting.

Stages of delay in oral cancer care evaluated at a tertiary health centre

BACKGROUND

To examine the stages of delay in presentation and management of oral cancer patients at University College Hospital Ibadan and compare findings with previous studies.

METHODS

A 20-year retrospective analysis of the delay stages among oral cancer patients that utilized patient's biodata and clinical data.

RESULT

169 oral cancer cases consisting of 127 carcinomas, 25 sarcomas and 17 lymphomas were analyzed. There was significant difference in the mean evolution time (ET) according to histological type (oral carcinoma = 282.8 +/- 414, oral sarcomas = 219.2 +/- 247.3 and oral lymphomas 105.5 +/- 115 days; p = 0.001). Patient's delay was more than professional delay for all cancer types (65.9%, 59.1% and 60.1% for carcinomas, sarcomas and lymphomas respectively). There was a significant difference in the mean ET of the early stage cancers compared with the late stage cancers (mean = 137.2 +/- 99 and 266.4 +/- 355; p = 0.010).

CONCLUSION

A combination of patients and professional delay negatively influenced the management of oral cancer patients but the patient's delay formed the bulk of this combination in our center.

Evidence for a role for a Plasmodium falciparum homologue of Sec31p in the export of proteins to the surface of malaria parasite-infected erythrocytes

The malaria parasite, Plasmodium falciparum, spends part of its life cycle inside the enucleated erythrocytes of its human host. The parasite modifies the cytoplasm and plasma membrane of its host cell by exporting proteins beyond the confines of its own plasma membrane. We have previously provided evidence that a plasmodial homologue of the COPII protein, Sar1p, is involved in the trafficking of proteins across the erythrocyte cytoplasm. We have now characterised an additional plasmodial COPII protein homologue, namely Sec31p. Recombinant proteins corresponding to the WD-40 and the intervening domains of the PfSec31p sequence were used to raise antibodies. The affinity-purified antisera recognised a protein with an apparent relative molecular mass of 1.6×105 on western blots of malaria parasite-infected erythrocytes but not on blots of uninfected erythrocytes. PfSec31p was shown to be largely insoluble in nonionic detergent, suggesting cytoskeletal attachment. Confocal immunofluorescence microscopy of malaria parasite-infected erythrocytes was used to show that PfSec31p is partly located within the parasite and partly exported to structures outside the parasite in the erythrocyte cytoplasm. We have also shown that PfSec31p and PfSar1p occupy overlapping locations. Furthermore, the location of PfSec31p overlaps that of the cytoadherence-mediating protein PfEMP1. These data support the suggestion that the malaria parasite establishes a vesicle-mediated trafficking pathway outside the boundaries of its own plasma membrane – a novel paradigm in eukaryotic biology.

Mycoflora of post-harvest maize and wheat grains and the implication of their contamination by molds

Thirteen fungi including toxigenic Aspergillus nidulans and A. clavatus were isolated from the grains. The isolated fungi grew well at 25-30 degrees C. A. clavatus and A. nidulans were grown in liquid maize yeast extract medium and wheat yeast extract medium. Both fungi produced amylases on the two media and on the basal medium at 30 degrees C. During incubation more total reducing sugars were detected in maize grains than in wheat while non-reducing sugars were detected than reducing sugars in both grains. A. clavatus showed highest amylase activities at 25-30 degrees C and at a pH 7-8 while 30 degrees C and pH 6.0 were the optimum conditions for highest amylase activities of A. nidulans. During incubation with both fungi a decrease in the protein and carbohydrate contents of both grains was recorded while more fat was accumulated in the grains.