Adapting international clinical trials during COVID-19 and beyond

BACKGROUND

The COVID-19 pandemic and resulting restrictions, particularly travel restrictions, have had significant impact on the conduct of global clinical trials. Our clinical trials programme, which relied on in-person visits for training, monitoring and capacity building across nine low- and middle-income countries, had to adapt to those unprecedented operational challenges. We report the adaptation of our working model with a focus on the operational areas of training, monitoring and cross-site collaboration.

THE NEW WORKING MODEL

Adaptations include changing training strategies from in-person site visits with three or four team members to a multi-pronged virtual approach, with generic online training for good clinical practice, the development of a library of study-specific training videos, and interactive virtual training sessions, including practical laboratory-focused training sessions. We also report changes from in-person monitoring to remote monitoring as well as the development of a more localized network of clinical trial monitors to support hybrid models with in-person and remote monitoring depending on identified risks at each site. We established a virtual network across different trial and study sites with the objective to further build capacity for good clinical practice-compliant antimalarial trials and foster cross-country and cross-study site collaboration.

CONCLUSION

The forced adaptation of these new strategies has come with advantages that we did not envisage initially. This includes improved, more frequent engagement through the established network with opportunities for increased south-to-south support and a substantially reduced carbon footprint and budget savings. Our new approach is challenging for study sites with limited prior experience but this can be overcome with hybrid models. Capacity building for laboratory-based work remains difficult using a virtual environment. The changes to our working model are likely to last, even after the end of the pandemic, providing a more sustainable and equitable approach to our research.

Screening for infectious maternal morbidity - knowledge, attitudes and perceptions among healthcare providers and managers in Malawi: a qualitative study

BACKGROUND

Maternal morbidity and mortality related to infection is an international public health concern, but detection and assessment is often difficult as part of routine maternity care in many low- and middle-income countries due to lack of easily accessible diagnostics. Front-line healthcare providers are key for the early identification and management of the unwell woman who may have infection. We sought to investigate the knowledge, attitudes, and perceptions of the use of screening tools to detect infectious maternal morbidity during and after pregnancy as part of routine antenatal and postnatal care. Enabling factors, barriers, and potential management options for the use of early warning scores were explored.

METHODS

Key informant interviews (n = 10) and two focus group discussions (n = 14) were conducted with healthcare providers and managers (total = 24) working in one large tertiary public hospital in Blantyre, Malawi. Transcribed interviews were coded by topic and then grouped into categories. Thematic framework analysis was undertaken to identify emerging themes.

RESULTS

Most healthcare providers are aware of the importance of the early detection of infection and would seek to better identify women with infection if resources were available to do so. In current practice, an early warning score was used in the high dependency unit only. Routine screening was not in place in the antenatal or postnatal departments. Barriers to implementing routine screening included lack of trained staff and time, lack of thermometers, and difficulties with the interpretation of the early warning scores. A locally adapted early warning screening tool was considered an enabler to implementing routine screening for infectious morbidity. Local ownership and clinical leadership were considered essential for successful and sustainable implementation for clinical change.

CONCLUSIONS

Although healthcare providers considered infection during and after pregnancy and childbirth a danger sign and significant morbidity, standardised screening for infectious maternal morbidity was not part of routine antenatal or postnatal care. The establishment of such a service requires the availability of free and easy to access rapid diagnostic testing, training in interpretation of results, as well as affordable targeted treatment. The implementation of early warning scores and processes developed in high-income countries need careful consideration and validation when applied to women accessing care in low resource settings.

Community-based participatory health research: principles and practice

Community-based participatory research (CBPR) is a collaborative approach to research that aims to improve the health of marginalized communities and reduce health disparities. It starts with a topic of concern for the community and involves iterative cycles of action and reflection to initiate change. Community members are involved as partners and trained as peer researchers to take an active role in the research process. Processes of capacity building and empowerment play a prominent role. As a general principle, participatory research does not primarily focus on health problems, but pays at least equal attention to the resources and capacities of communities. It places a strong focus on developing trust and reciprocity in research relationships.

Regarding methodology, various empirical research methods are used in CBPR study designs, including qualitative, quantitative, mixed-methods and arts-based methods. Arts-based methods such as photovoice, digital storytelling, mapping and drawings facilitate the expression of lived experience, including sensitive aspects, through creative verbal and non-verbal means. These methods expand the available means of expression and as such are highly valuable in research fields where verbal communication is challenged by language barriers and diverse cultural backgrounds as well as sensitive topics and experiences. Participatory health research has been conducted with diverse migrant and refugee groups internationally. Due to legal and other reasons, refugees may be limited in their capacities for participation. The presentation will discuss the strengths and limitations of CBPR including structural obstacles to equitable partnerships.

Menstrual cup use, leakage, acceptability, safety, and availability: a systematic review and meta-analysis

BACKGROUND

Girls and women need effective, safe, and affordable menstrual products. Single-use products are regularly selected by agencies for resource-poor settings; the menstrual cup is a less known alternative. We reviewed international studies on menstrual cup leakage, acceptability, and safety and explored menstrual cup availability to inform programmes.

METHODS

In this systematic review and meta-analysis, we searched PubMed, Cochrane Library, Web of Science, Popline, Cinahl, Global Health database, Emerald, Google Scholar, Science.gov, and WorldWideScience from database inception to May 14, 2019, for quantitative or qualitative studies published in English on experiences and leakage associated with menstrual cups, and adverse event reports. We also screened the Manufacturer and User Facility Device Experience database from the US Food and Drug Administration for events related to menstrual cups. To be eligible for inclusion, the material needed to have information on leakage, acceptability, or safety of menstrual cups. The main outcome of interest was menstrual blood leakage when using a menstrual cup. Safety outcomes of interest included serious adverse events; vaginal abrasions and effects on vaginal microflora; effects on the reproductive, digestive, or urinary tract; and safety in poor sanitary conditions. Findings were tabulated or combined by use of forest plots (random-effects meta-analysis). We also did preliminary estimates on costs and environmental savings potentially associated with cups. This systematic review is registered on PROSPERO, number CRD42016047845.

FINDINGS

Of 436 records identified, 43 studies were eligible for analysis (3319 participants). Most studies reported on vaginal cups (27 [63%] vaginal cups, five [12%] cervical cups, and 11 [25%] mixed types of cups or unknown) and 15 were from low-income and middle-income countries. 22 studies were included in qualitative or quantitative syntheses, of which only three were of moderate-to-high quality. Four studies made a direct comparison between menstrual cups and usual products for the main outcome of leakage and reported leakage was similar or lower for menstrual cups than for disposable pads or tampons (n=293). In all qualitative studies, the adoption of the menstrual cup required a familiarisation phase over several menstrual cycles and peer support improved uptake (two studies in developing countries). In 13 studies, 73% (pooled estimate: n=1144; 95% CI 59-84, I2=96%) of participants wished to continue use of the menstrual cup at study completion. Use of the menstrual cup showed no adverse effects on the vaginal flora (four studies, 507 women). We identified five women who reported severe pain or vaginal wounds, six reports of allergies or rashes, nine of urinary tract complaints (three with hydronephrosis), and five of toxic shock syndrome after use of the menstrual cup. Dislodgement of an intrauterine device was reported in 13 women who used the menstrual cup (eight in case reports, and five in one study) between 1 week and 13 months of insertion of the intrauterine device. Professional assistance to aid removal of menstrual cup was reported among 47 cervical cup users and two vaginal cup users. We identified 199 brands of menstrual cup, and availability in 99 countries with prices ranging US$0·72-46·72 (median $23·3, 145 brands).

INTERPRETATION

Our review indicates that menstrual cups are a safe option for menstruation management and are being used internationally. Good quality studies in this field are needed. Further studies are needed on cost-effectiveness and environmental effect comparing different menstrual products.

FUNDING

UK Medical Research Council, Department for International Development, and Wellcome Trust.

The assessment of gestational age: a comparison of different methods from a malaria pregnancy cohort in sub-Saharan Africa

BACKGROUND

Determining gestational age in resource-poor settings is challenging because of limited availability of ultrasound technology and late first presentation to antenatal clinic. Last menstrual period (LMP), symphysio-pubis fundal height (SFH) and Ballard Score (BS) at delivery are therefore often used. We assessed the accuracy of LMP, SFH, and BS to estimate gestational age at delivery and preterm birth compared to ultrasound (US) using a large dataset derived from a randomized controlled trial in pregnant malaria patients in four African countries.

METHODS

Mean and median gestational age for US, LMP, SFH and BS were calculated for the entire study population and stratified by country. Correlation coefficients were calculated using Pearson's rho, and Bland Altman plots were used to calculate mean differences in findings with 95% limit of agreements. Sensitivity, specificity, positive predictive value and negative predictive value were calculated considering US as reference method to identify term and preterm babies.

RESULTS

A total of 1630 women with P. falciparum infection and a gestational age > 24 weeks determined by ultrasound at enrolment were included in the analysis. The mean gestational age at delivery using US was 38.7 weeks (95%CI: 38.6-38.8), by LMP, 38.4 weeks (95%CI: 38.0-38.9), by SFH, 38.3 weeks (95%CI: 38.2-38.5), and by BS 38.0 weeks (95%CI: 37.9-38.1) (p < 0.001). Correlation between US and any of the other three methods was poor to moderate. Sensitivity and specificity to determine prematurity were 0.63 (95%CI 0.50-0.75) and 0.72 (95%CI, 0.66-0.76) for LMP, 0.80 (95%CI 0.74-0.85) and 0.74 (95%CI 0.72-0.76) for SFH and 0.42 (95%CI 0.35-0.49) and 0.77 (95%CI 0.74-0.79) for BS.

CONCLUSIONS

In settings with limited access to ultrasound, and in women who had been treated with P. falciparum malaria, SFH may be the most useful antenatal tool to date a pregnancy when women present first in second and third trimester. The Ballard postnatal maturation assessment has a limited role and lacks precision. Improving ultrasound facilities and skills, and early attendance, together with the development of new technologies such as automated image analysis and new postnatal methods to assess gestational age, are essential for the study and management of preterm birth in low-income settings.

Risk factors and pregnancy outcomes associated with placental malaria in a prospective cohort of Papua New Guinean women

Background

Plasmodium falciparum in pregnancy results in substantial poor health outcomes for both mother and child, particularly in young, primigravid mothers who are at greatest risk of placental malaria (PM) infection. Complications of PM include maternal anaemia, low birth weight and preterm delivery, which contribute to maternal and infant morbidity and mortality in coastal Papua New Guinea (PNG).

Methods

Placental biopsies were examined from 1451 pregnant women who were enrolled in a malaria prevention study at 14–26 weeks gestation. Clinical and demographic information were collected at first antenatal clinic visits and women were followed until delivery. Placental biopsies were collected and examined for PM using histology. The presence of infected erythrocytes and/or the malaria pigment in monocytes or fibrin was used to determine the type of placental infection.

Results

Of 1451 placentas examined, PM infection was detected in 269 (18.5%), of which 54 (3.7%) were acute, 55 (3.8%) chronic, and 160 (11.0%) were past infections. Risk factors for PM included residing in rural areas (adjusted odds ratio (AOR) 3.65, 95% CI 1.76–7.51; p ≤ 0.001), being primigravid (AOR 2.45, 95% CI 1.26–4.77; p = 0.008) and having symptomatic malaria during pregnancy (AOR 2.05, 95% CI 1.16–3.62; p = 0.013). After adjustment for covariates, compared to uninfected women, acute infections (AOR 1.97, 95% CI 0.98–3.95; p = 0.056) were associated with low birth weight babies, whereas chronic infections were associated with preterm delivery (AOR 3.92, 95% CI 1.64–9.38; p = 0.002) and anaemia (AOR 2.22, 95% CI 1.02–4.84; p = 0.045).

Conclusions

Among pregnant PNG women receiving at least one dose of intermittent preventive treatment in pregnancy and using insecticide-treated bed nets, active PM infections were associated with adverse outcomes. Improved malaria prevention is required to optimize pregnancy outcomes.

Evidence for enzootic circulation of Rift Valley fever virus among livestock in Cameroon

Rift Valley fever virus (RVFV) is an arthropod-borne pathogen, causing serious epidemics in Africa and the Arabian Peninsula. In Cameroon serological data indicate the presence of RVFV, but active circulation of RVFV, causing clinical infections has not been proven yet. For this purpose we carried out a serological and molecular study on a total of 1953 randomly selected serum samples of small ruminants and cattle, which were collected in years 2013 and 2014 in Cameroon. In a first step, sera were screened serologically using a variety of assay formats to reveal RVFV specific antibodies. At the second stage, seropositive specimen were assessed for acute RVFV infections via IgM-specific ELISA and quantitative real-time RT-PCR. Our data show a significant difference in the antibody prevalence in cattle (13.5% [95% confidence interval: 11.4-15.7]) and small ruminants (3.4% [95% confidence interval: 2.3-4.7]), with indications for annual fluctuations and significant regional differences of seropositivity. One small ruminant and three bovines were eventually found to be positive in IgM ELISA and indications for viremia were found in one bovine by RVFV genome detection using quantitative real-time RT-PCR. The results of this study therefore corroborate the presence of acute RVFV-infection and its circulation in Cameroon.

Decreasing malaria prevalence and its potential consequences for immunity in pregnant women

BACKGROUND

As malaria control is intensified, pregnant women may be less exposed to malaria, thus affecting the acquisition of protective antibody.

METHODS

Plasma samples were collected from Malawian and Papua New Guinean (PNG) pregnant women enrolled over 7-year periods, during which malaria prevalence fell by over two thirds. Immunoglobulin G (IgG) levels to schizont extract, merozoite antigens, and VAR2CSA-DBL5ε were measured by enzyme-linked immunosorbent assay (ELISA). Levels of IgG to variant surface antigens of infected erythrocytes (IEs) and merozoites and levels of opsonizing IgG to IEs were measured by flow cytometry.

RESULTS

In both settings, levels of antibodies in pregnant women to recombinant antigens and to intact IEs but not of opsonizing antibodies decreased over time. After adjustment for coverage with insecticide-treated bed nets (ITNs), these differences disappeared in the Malawian cohort, whereas in the PNG cohort, time was independently associated with a decrease in several antibody responses measured by ELISA.

CONCLUSIONS

The impact of falling parasite prevalence on anti-Plasmodium falciparum serological indicators in pregnant women varies by setting. Increased ITN coverage may affect development of antibodies to recombinant antigens, but levels of opsonizing IgG remained stable over time. Opsonizing IgG against placental-binding IEs may persist, thus offering longer-lasting protection against malaria during pregnancy.

Travellers as sentinels: Assaying the worldwide distribution of polymorphisms associated with artemisinin combination therapy resistance in Plasmodium falciparum using malaria cases imported into Scotland

There is growing evidence that Plasmodium falciparum parasites in southeastern Asia have developed resistance to artemisinin combination therapy. The resistance phenotype has recently been shown to be associated with four single nucleotide polymorphisms in the parasite's genome. We assessed the prevalence of two of these single nucleotide polymorphisms in P. falciparum parasites imported into Scotland between 2009 and 2012, and in additional field samples from six countries in southeastern Asia. We analysed 28 samples from 11 African countries, and 25 samples from nine countries in Asia/southeastern Asia/Oceania. Single nucleotide polymorphisms associated with artemisinin combination therapy resistance were not observed outside Thailand and Cambodia.

Abstract P4-06-20: The Role of Aktl in RhoC GTPase-Mediated Inflammatory Breast Cancer Invasion

Inflammatory breast cancer (IBC) is a highly aggressive form of locally advanced breast cancer, distinguished from other types of breast cancer by clinical, pathologic, and molecular features. It is clinically distinguished by rapid onset of primary skin changes, including redness of the skin, nipple retraction, and peau d’ aurange. Inflammatory breast cancer accounts for approximately 6-9% of new breast cancers in the United States annually and although the number of women affected by IBC is relatively modest, the overall the 5- and 10-year disease-free survival rates are less than 45% and 20%, respectively, making IBC the most lethal form of breast cancer. Evidence has suggested a role for the phosphoinositide 3-kinase/Akt (Protein Kinase B) signaling pathway in cellular motility, invasion, and metastasis. Recent evidence has shown activation of Akt2 (PKBβ) in breast cancer and its involvement in metastasis. However, the opposite appears to be true in inflammatory breast cancer (IBC), where Akt1 is involved in cellular motility and invasion. We have demonstrated a role for RhoC in conferring a highly invasive phenotype to IBC cells and are suggesting here that Akt1 phosphorylation of RhoC leads to cellular invasion. Farnesyltransferase inhibitors (FTIs) interfere with GTPase farnesylation and activity and we have shown that FTI treatment of SUM149 IBC cells leads to inhibition of the RhoC GTPase-induced invasive phenotype of IBC. RhoC is not a direct target of FTI action, however, its relative, RhoB, is a putative FTI target. It has been shown that FTI inhibition of farnesylated RhoB (fRhoB) leads to an accumulation of geranylgeranylated RhoB (ggRhoB) in the cell, which can interfere with GTPase signals and mimics the effects of FTI in IBC cells. RhoB GTPase, particularly ggRhoB, is an intracellular trafficking protein that regulates cellular localization of Akt1, thus affecting its activation. In this present study our primary objective was to examine the role of Akt1 and RhoC phosphorylation in IBC cell invasion as well as the localization of these various molecules within IBC cells upon FTI treatment. The SUM149 inflammatory breast cancer cell line overexpresses RhoC, lacks the PTEN gene, and consequently expresses a constitutively active Akt. Using the SUM149 cell line, we demonstrate that RhoC is a reputed substrate for Akt phosphorylation. We are able to decrease phospho-RhoC levels and inhibit SUM149 cellular invasion through inhibiting Akt1 activation with commercially available Akt inhibitors and siAkt1. Through immunofluorescence and protein localization experiments we are able to see a shift of phosphorylated Akt1 from the cell cytoplasm to the nucleus upon FTI treatment. We also observe accumulation of ggRhoB over time with localization of Akt1 away from the plasma membrane. These results suggest that Akt, specifically Akt1, phosphorylation of RhoC in inflammatory breast cancer cells is required for cellular invasion. We are also able to suggest that FTI treatment of IBC cells leads to increased ggRhoB levels, which may lead to changes in localization of proteins that will affect RhoC GTPase and the metastatic IBC phenotype.

Citation Information: Cancer Res 2010;70(24 Suppl):Abstract nr P4-06-20.

Maternal morbidity and mortality in peri-urban Kenya--assessing progress in improving maternal healthcare

OBJECTIVE

Improving quality of maternal healthcare delivery is pivotal to reversing the trend of maternal health in developing countries and consequently, achieving the 5th millennium goal of reducing maternal mortality and improving universal access to reproductive health. Periodic facility-based reviews of maternal morbidity and mortality are crucial to improving quality of care delivered.

METHODS

This retrospective study was conducted in PCEA Kikuyu Hospital, Kenya. Data on sociodemographics, recorded antenatal care activities, maternal morbidities and deaths were elicited from case notes of all pregnancies and births over a 2 year period and subsequently analyzed.

RESULTS

There were 1716 deliveries during the period. 1405 (91%) of the women booked for antenatal care; 1068 (57.3%) had at least 3 visits before delivery. 842 (45.9%) were either untested for Human Immunodeficiency Virus or their results were not documented; 55 (3%) tested positive. The caesarean section rate was 27.4% (n=470); PMTCT (Prevention of Mother to Child Transmission) constituted 1.6% (10) of the indications. Urinary tract infection was the commonest maternal illness in pregnancy (14.5%, n=270), however, it was not found to be associated with any adverse outcome. Genital tract trauma was the commonest morbidity suffered by the women during delivery (90.6%, n=800). Psychological disorders constituted 5.3% (7) of reported postpartum complications. There were 2 maternal deaths out of 1673 live births, giving a maternal mortality ratio of 119.55 per 100,000 live births. The deaths resulted from septic abortion and eclampsia.

CONCLUSION

Urinary tract infection is an important cause of maternal illness during pregnancy. Routine screening is recommended. PMTCT needs further consolidation to increase the number of screened women and ensure those who need interventions like caesarean sections get access to them. Diagnosis and management of psychological disorders in pregnancy remain unsatisfactory. Further studies to identify the true burden of these conditions are needed.

Vasopressin in Cerebrospinal Fluid (CSF) and Plasma of Conscious Rabbits - Circadian Variations

Determination of AVP in the CSF and plasma of conscious, freely moving and normally hydrated rabbits yielded in the CSF a value three times higher than in plasma, while revealing opposite rhythmic daily patterns for both compartments.

International network for capacity building for the control of emerging viral vector-borne zoonotic diseases: ARBO-ZOONET

Arboviruses are arthropod-borne viruses, which include West Nile fever virus (WNFV), a mosquito-borne virus, Rift Valley fever virus (RVFV), a mosquito-borne virus, and Crimean-Congo haemorrhagic fever virus (CCHFV), a tick-borne virus. These arthropod-borne viruses can cause disease in different domestic and wild animals and in humans, posing a threat to public health because of their epidemic and zoonotic potential. In recent decades, the geographical distribution of these diseases has expanded. Outbreaks of WNF have already occurred in Europe, especially in the Mediterranean basin. Moreover, CCHF is endemic in many European countries and serious outbreaks have occurred, particularly in the Balkans, Turkey and Southern Federal Districts of Russia. In 2000, RVF was reported for the first time outside the African continent, with cases being confirmed in Saudi Arabia and Yemen. This spread was probably caused by ruminant trade and highlights that there is a threat of expansion of the virus into other parts of Asia and Europe. In the light of global warming and globalisation of trade and travel, public interest in emerging zoonotic diseases has increased. This is especially evident regarding the geographical spread of vector-borne diseases. A multi-disciplinary approach is now imperative, and groups need to collaborate in an integrated manner that includes vector control, vaccination programmes, improved therapy strategies, diagnostic tools and surveillance, public awareness, capacity building and improvement of infrastructure in endemic regions.

International network for capacity building for the control of emerging viral vector-borne zoonotic diseases: ARBO-ZOONET

Arboviruses are arthropod-borne viruses, which include West Nile fever virus (WNFV), a mosquito-borne virus, Rift Valley fever virus (RVFV), a mosquito-borne virus, and Crimean-Congo haemorrhagic fever virus (CCHFV), a tick-borne virus. These arthropod-borne viruses can cause disease in different domestic and wild animals and in humans, posing a threat to public health because of their epidemic and zoonotic potential. In recent decades, the geographical distribution of these diseases has expanded. Outbreaks of WNF have already occurred in Europe, especially in the Mediterranean basin. Moreover, CCHF is endemic in many European countries and serious outbreaks have occurred, particularly in the Balkans, Turkey and Southern Federal Districts of Russia. In 2000, RVF was reported for the first time outside the African continent, with cases being confirmed in Saudi Arabia and Yemen. This spread was probably caused by ruminant trade and highlights that there is a threat of expansion of the virus into other parts of Asia and Europe. In the light of global warming and globalisation of trade and travel, public interest in emerging zoonotic diseases has increased. This is especially evident regarding the geographical spread of vector-borne diseases. A multi-disciplinary approach is now imperative, and groups need to collaborate in an integrated manner that includes vector control, vaccination programmes, improved therapy strategies, diagnostic tools and surveillance, public awareness, capacity building and improvement of infrastructure in endemic regions.

INNO-206, the (6-maleimidocaproyl hydrazone derivative of doxorubicin), shows superior antitumor efficacy compared to doxorubicin in different tumor xenograft models and in an orthotopic pancreas carcinoma model

The (6-maleimidocaproyl)hydrazone derivative of doxorubicin (INNO-206) is an albumin-binding prodrug of doxorubicin with acid-sensitive properties that is being assessed clinically. The prodrug binds rapidly to circulating serum albumin and releases doxorubicin selectively at the tumor site. This novel mechanism may provide enhanced antitumor activity of doxorubicin while improving the overall toxicity profile. Preclinically, INNO-206 has shown superior activity over doxorubicin in a murine renal cell carcinoma model and in breast carcinoma xenograft models. In this work, we compared the antitumor activity of INNO-206 and doxorubicin at their respective maximum tolerated doses in three additional xenograft models (breast carcinoma 3366, ovarian carcinoma A2780, and small cell lung cancer H209) as well as in an orthotopic pancreas carcinoma model (AsPC-1). INNO-206 showed more potent antitumor efficacy than free doxorubicin in all tumor models and is thus a promising clinical candidate for treating a broad range of solid tumors.

Failure to detect Plasmodium vivax in West and Central Africa by PCR species typing

Background

Plasmodium vivax is estimated to affect 75 million people annually. It is reportedly absent, however, from west and central Africa due to the high prevalence of the Duffy negative phenotype in the indigenous populations. Despite this, non-African travellers consistently return to their own countries with P. vivax malaria after visiting this region. An attempt was made, therefore, to detect the presence of P. vivax parasites in blood samples collected from the indigenous populations of west and central Africa.

Methods

Parasite species typing (for all four human malaria parasites) was carried out by PCR on 2,588 blood samples collected from individuals from nine African malaria-endemic countries.

Results

Most infections (98.5%) were Plasmodium falciparum, Plasmodium malariae was identified in 8.5% of all infections, and Plasmodium ovale in 3.9%. The prevalence of both parasites varied greatly by country. Only one case of P. vivax was detected from Sao Tome, an island off the west coast of Africa, confirming the scarcity of this parasite in Africa.

Conclusion

The prevalence of P. vivax in local populations in sub-Saharan Africa is very low, despite the frequent identification of this parasite in non-African travellers.

Development and evaluation of a loop-mediated isothermal amplification method for diagnosis of tropical theileriosis

A loop-mediated isothermal amplification (LAMP) assay was developed and evaluated for diagnosis of tropical theileriosis. A set of six primers was designed based on the unique gene of Theileria annulata (Theileria annulata strain Ankara hypothetical protein (GeneDB TA04795). The protocol for the reaction was setup and the specificity and sensitivity of the assay were established. The specificity experiment showed that LAMP primers amplified T. annulata DNA successfully, while no amplification was seen for Theileria parva, Theileria mutans, Theileria sergenti, Theileria sinensis, Babesia bovis as well as bovine genomic DNA and water control. When the sensitivity of LAMP assay was compared with that of conventional PCR a 10-fold higher sensitivity was found, with a detection limit of 10 pg/microl of genomic DNA isolated from a T. annulata-infected cell line. The LAMP product was confirmed by restriction digestion and staining with SYBR Green I. Furthermore, the LAMP assay was applied for the diagnosis of T. annulata in field samples and compared with reverse line blot (RLB), demonstrating that results of the LAMP assay corresponded to those of RLB. These results indicate that the LAMP assay is rapid and simple to run, cost-effective, sensitive and specific and has potential usefulness for application in epidemiological studies on T. annulata infection of cattle.

Prevalence of Brucella abortus antibodies in serum of Holstein cattle in Cameroon

Holstein cattle of a small scale dairy production systems were screened for Brucella abortus antibodies in 21 villages in Cameroon by ELISA. Results show a general seroprevalence of 8.4% in Holstein cattle. Of the 192 cows tested, 14 were infected giving a within-sex seroprevalence of 7.3% while 6/74 bulls were infected with a seroprevalence of 8%. There was no evidence (P=0.11) of differences in seroprevalence between age groups although animals above one year and below three years accounted for nearly half of the infected animals. 64% of infected animals were found in three locations (P=0.015): Kutaba (32%), Bamendankwe (16%) and Finge (16%). A specific control programme should be organized at these locations. Measures should be taken to ensure the eradication of the disease within the population and sound control measures adopted to avoid a further spread of the disease to larger cattle populations. Infected animals should be slaughtered systematically. All farmers should be advised to boil milk before consumption. Vaccination against Brucella abortus should be instituted and use of artificial insemination propagated. In order to ensure a productive and healthy population of Holstein cows within the dairy production scheme, regular Brucella testing should be instituted.

Simian immunodeficiency virus vector pseudotypes differ in transduction efficiency and target cell specificity in brain

Lentiviral vectors have proven to be promising tools for transduction of brain cells in vivo and in vitro. In this study, we have examined the central nervous system (CNS) transduction efficiencies and patterns of a self-inactivating simian immunodeficiency virus (SIVmac)-derived lentiviral vector pseudotyped with glycoproteins from the vesicular stomatitis virus (VSV-G), the amphotropic murine leukemia virus (MLV4070Aenv), the lymphocytic choriomeningitis virus (LCMV-GP), the Ross River virus (RRV-GP) and the rabies virus (RV-G). All glycoproteins were efficiently incorporated into SIV virions, allowing efficient transduction of neuronal cell lines as well as of primary dissociated mouse brain cell cultures. After injection of highly concentrated vector stocks into the striatum of adult mice, quantitative analyses revealed high transduction efficiency with VSV-G pseudotypes, while LCMV-GP and RV-G pseudotypes exhibited moderate transduction efficiencies. MLV4070Aenv and RRV-GP pseudotypes, however, showed only weak levels of transduction after stereotactic injection into the brain. Regarding cell tropism in vivo, VSV-G-pseudotyped SIV vectors transduced neuronal as well as glial cells, whereas all other pseudotypes preferentially transduced neuroglial cells. In addition, we analyzed the influence of the central polypurine tract (cPPT) in context of the VSV-G-pseudotyped SIV transfer vector for infection of brain cells. Deletion of the cPPT sequence from the transfer vector decreased the in vivo transduction efficiency by fourfold, and, more importantly, this modification changed the transduction pattern, since these vectors were no longer able to infect neuronal cells in vivo. Vector injection into the brain did elicit a humoral immune response in the injected hemisphere; however, no gross signs of inflammation could be detected. Analysis of the biodistribution of the vector revealed that, besides the injected brain region, no vector-specific sequences could be detected in any of the organs evaluated. These data indicate SIV vectors as efficient gene delivery vehicles for the treatment of neurodegenerative diseases.

The International Atomic Energy Agency (IAEA) experience in the development of validation systems leading to the OIE certification of diagnostic assays

For the past 15 years, the International Atomic Energy Agency (IAEA) has had a major interest in helping its member states to diagnose livestock diseases through the development and validation of diagnostic tests for trans-boundary animal diseases. In November, 2007, an IAEA consultants meeting attended by experts, OIE members and producers reviewed the OIE process for the recognition of tests to date. Conclusions concerning the application procedure were tabled by the general meeting and then specific producer recommendations were made. Both are shown below, along with conclusions regarding referencing in general. Some of the points brought up suggest major changes in the idea of trade prescription and test status.

Aspects of kit validation for tests used for the diagnosis and surveillance of livestock diseases: producer and end-user responsibilities

The Joint Food and Agriculture Organization/International Atomic Energy Agency (IAEA) Division of Nuclear Techniques in Food and Agriculture, based at the IAEA in Vienna, Austria, has extensive experience in helping to develop and validate assays and has provided strong support in developing World Organisation for Animal Health (OIE) norms. This paper will focus on enzyme-linked immunosorbent assay and polymerase chain reaction as the major technologies exploited in diagnosis and surveillance. Problems involving the terminology and factors in kit production, supply and validation are examined, in particular emphasising the importance of robustness and ruggedness of tests. The authors discuss the responsibilities of the various stakeholders (producers, distributors, users, and national/international organisations) in achieving quality controlled data to solve diagnostic and surveillance problems. The roles of internal quality control (internal proficiency testing) and external quality assurance (external proficiency testing) as well as aids to solving problems with kits are examined.

Early visual recovery after excimer laser surgery for myopia: the Melbourne OmniMed results

BACKGROUND AND OBJECTIVE

Although the refractive outcome can change for months after photorefractive keratectomy (PRK), early visual results are of particular importance during pre-operative counseling of prospective PRK candidates. The expected vision in the first week post-operatively, following 6.0 mm or larger zone photoablation for myopia with the Summit OmniMed (Apex) laser, has not been analyzed in the literature to date. This study is intended to provide an indication of the early visual acuity that may be experienced by a patient undergoing PRK for myopia.

PATIENTS AND METHODS

The visual acuity recorded for 123 consecutive patients, (79 low myopes [-1.00 to -5.90 diopters (D)], 44 high extreme myopes [-6.00 to -19.00 D]), one week after they had undergone PRK, was analyzed. All patients included in the study had undergone PRK with the Summit OmniMed (Apex) excimer laser, leaving small degrees of astigmatism uncorrected.

RESULTS

One week after PRK, uncorrected visual acuity was better for low myopes than high myopes. Of the low myopes, 83.0% were 20/40 or better compared with high myopes of whom 61.4% were 20/40 or better.

CONCLUSION

Patients can be counseled that functional vision will be present in the period immediately after re-epithelialization.

Dopamine infusion in patients with hepatic encephalopathy: plasma levels and haemodynamic changes

During a constant infusion of dopamine (DA 4.5 micrograms/kg/min), the plasma levels of DA reached at 30 min of infusion were 81 +/- 6.9 ng/ml and 71.6 +/- 14.8 ng/ml in patients with hepatic encephalopathy (HE) and control patients, respectively. In both groups of patients, the plasma levels of DA did not change between 30 and 60 min of continuous DA infusion. The DA infusion was associated with an increase of arterial blood pressure, heart rate and cardiac index. In the patients with HE, the increase in cardiac index was directly correlated with the plasma level of DA (r = 0.843, p less than 0.01). The present results clearly demonstrate that in HE circulating DA does not accumulate during continuous infusion of DA. They further provide evidence that the increase in circulating catecholamines in HE reflects increased release from the sympatho-adrenal system.

Malignant endovascular papillary angioendothelioma (Dabska tumor). A case report and review of the literature

Malignant endovascular papillary angioendothelioma is a rare vascular tumor of childhood that was first defined by Dabska in 1969. Microscopically, this tumor is composed of anastomosing vascular channels, some of which contain papillary projections or tuft-like structures sometimes resembling renal glomeruli. Although cases have been reported with metastases to regional lymph nodes, the long term prognosis for patients with these tumors is generally good. We have studied this tumor by light and electron microscopy as well as immunohistochemical techniques in a 10-year-old boy. A review of the literature on this rare entity is presented.

Preservation of incretin activity after removal of gastric inhibitory polypeptide (GIP) from rat gut extracts by immunoadsorption

The action of watery rat gut extracts on glucose-induced insulin release in anaesthetized rats was examined before and after removal of GIP by immunoadsorption. Infusions of GIP-containing rat gut extracts nearly doubled the insulin release induced by intravenous glucose (1 g X kg -1 X h -1). Peak insulin secretion was 98 +/- 11 mU/l (mean +/- SEM) after intravenous glucose and increased to 178 +/- 16 mU/l following infusion of glucose plus gut extract (p less than 0.005). After injection of GIP antiserum in sufficient amounts to neutralize the GIP activity in the gut extract preparation, the additional insulin release due to the gut extract was reduced by only 30%. After complete removal of GIP from gut extracts by immuno-absorption, more than 50% of the incretin effect remained. These data suggest that the insulinotropic activity of rat gut extracts can only be partially related to GIP. The existence of additional insulinotropic gut factors which may also be released following oral glucose is postulated.

[Self-control of blood sugar (author's transl)]

Nine well-trained insulin-dependent diabetics checked their blood sugar using a test strip (Haemo-Glukotest 20-800) and three reflectometers (Reflomat, Dextrometer, Glucosemeter) in order to compare the accuracy of the three instruments with that of the test strip. 227 single checks were carried out, and the blood sugar was checked by means of the hexokinase method. The correlation of the four methods with the hexokinase method was comparable: Reflomat r = 0.95, Dextrometer r = 0.94, Haemo-Glukotest 20-800 r = 0.93, Glucosemeter r = 0.91. Classification of the results into various measuring ranges yielded a comparable accuracy of all four methods between 40 and 250 mg/dl; above 250 mg/dl, there was a considerable decrease in accuracy even of the reflectometers. Hence, the reflectometers do not offer any significant advantages over the visual Haemo-Glukotest 20-800 readings as far as self-control of blood sugar by the diabetic is concerned.