Entry characteristics and performance in a Masters module in Tropical Medicine: a 5-year analysis.

OBJECTIVES: Postgraduate courses can contribute to better-qualified personnel in resource-limited settings. We aimed to identify how entry characteristics of applicants predict performance in order to provide support measures early. METHODS: We describe demographic data and end-of-module examination marks of medical doctors who enrolled in a first semester module of two one-year MSc programmes between 2010 and 2014. We used t-tests and one-way anova to compare, and post hoc tests to locate differences of mean marks between categories of entry characteristics in univariate analysis. After exclusion of collinear variables, multiple regression examined the effect of several characteristics in multivariable analysis. RESULTS: Eighty-nine students (47% male) with a mean age of 32 (SD 6.4) years who received their medical degree in the UK (19%), other European (22%), African (35%) or other countries (24%) attended the 3-months module. Their mean mark was 69.1% (SD 10.9). Medical graduates from UK universities achieved significantly higher mean marks than graduates from other countries. Students' age was significantly negatively correlated with the module mark. In multiple linear regression, place of medical degree (ß = -0.44, P < 0.001) and time since graduation (ß = -0.28, P = 0.007) were strongest predictors of performance, explaining 32% of the variation of mean marks. CONCLUSION: Students' performance substantially differs based on their entry criteria in this 1st semester module. Non-UK graduates and mature students might benefit from early support.

Duplex-forming oligocarbamates with tunable nonbonding sites.

In biopolymers such as proteins and nucleic acids, monomer sequence encodes for highly specific intra- and intermolecular interactions that direct self-assembly into complex architectures with high fidelity. This remarkable structural control translates into precise control over the properties of the biopolymer. Polymer scientists have sought to achieve similarly precise control over the structure and function of synthetic assemblies. A common strategy for achieving this goal has been to exploit existing biopolymers, known to associate with specific geometries and stoichiometries, for the assembly of synthetic building blocks. However, such systems are neither scalable nor amenable to the relatively harsh conditions required by various materials science applications, particularly those involving non-aqueous environments. To overcome these limitations, we have synthesized sequence-defined oligocarbamates (SeDOCs) that assemble into duplexes through complementary hydrogen bonds between thymine (T) and diaminotriazine (D) pendant groups. The SeDOC platform makes it simple to incorporate non-hydrogen-bonding sites into an oligomer's array of recognition motifs, thereby enabling an investigation into this unexplored handle for controlling the hybridization of complementary ligands. We successfully synthesized monovalent, divalent, and trivalent SeDOCs and characterized their self-assembly via diffusion ordered spectroscopy, 1H-NMR titration, and isothermal titration calorimetry. Our findings reveal that the binding strength of monovalent oligomers with complementary pendant groups is entropically driven and independent of monomer sequence. The results further show that the hybridization of multivalent oligomers is cooperative, that their binding enthalpy (ΔH) and entropy (TΔS) depend on monomer sequence, and that sequence-dependent changes in ΔH and TΔS occur in tandem to minimize the overall change in binding free energy.

Synthetically encoded complementary oligomers.

Creating the next generation of advanced materials will require controlling molecular architecture to a degree typically achieved only in biopolymers. Sequence-defined polymers take inspiration from biology by using chain length and monomer sequence as handles for tuning structure and function. These sequence-defined polymers can assemble into discrete structures, such as molecular duplexes, via reversible interactions between functional groups. Selectivity can be attained by tuning the monomer sequence, thereby creating the need for chemical platforms that can produce sequence-defined polymers at scale. Developing sequence-defined polymers that are specific for their complementary sequence and achieve their desired binding strengths is critical for producing increasingly complex structures for new functional materials. In this Review Article, we discuss synthetic platforms that produce sequence-defined, duplex-forming oligomers of varying length, strength and association mode, and highlight several analytical techniques used to characterize their hybridization.

Characteristics of adults and children diagnosed with tuberculosis in Lilongwe, Malawi: findings from an integrated HIV/TB clinic.

OBJECTIVES: To describe initial registration characteristics of adult and paediatric TB patients at a large, public, integrated TB and HIV clinic in Lilongwe, Malawi, between January 2008 and December 2010. METHODS: Routine data on patient with TB category and TB type, stratified by HIV and ART status, were used to explore differences in proportions among TB only, TB/HIV co-infected patients not on ART and TB/HIV co-infected patients on ART using chi-square tests. Trends over time illustrate strengths and weaknesses of integrated service provision. RESULTS: Among 10 143 adults, HIV ascertainment and ART uptake were high and increased over time. The proportion of relapse was highest among those on ART (5%). The proportion of smear-positive pulmonary TB (PTB) was highest among HIV-negative patients with TB (34.9%); extra-pulmonary TB (EPTB) was lowest among TB only (16.2%). Among 338 children <15 years, EPTB and smear-positive PTB were more common among TB-only patients. Time trends showed significant increases in the proportion of adults with smear-positive PTB and the proportion of adults already on ART before starting TB treatment. However, some co-infected patients still delay ART initiation. CONCLUSIONS: HIV ascertainment and ART uptake among co-infected patients are successful and improving over time. However, delays in ART initiation indicate some weakness linking TB/HIV patients into ART during TB follow-up care. Improved TB diagnostics and screening efforts, especially for paediatric patients, may help improve quality care for co-infected patients. These results may aid efforts to prioritise TB and HIV prevention, education and treatment campaigns for specific populations.

A mixed-methods study on evaluating an updated, francophone version of ETAT+ training in Madagascar.

Background: Madagascar needs major efforts to achieve the UN Sustainable Development Goals, despite the considerable reduction of child mortality during past years. In this context, implementation of emergency triage assessment and treatment (ETAT) plays an important role. In recent years, ETAT training activities rarely took place in Madagascar. To strengthen ETAT in Madagascar, a pilot training course was conducted in December 2019 at the University Hospital Mahajanga. Objectives: This study aims to evaluate if the ETAT+ pilot training content matches clinical needs in Madagascar and whether participants achieved their learning objectives. Methods: In this cross-sectional mixed-methods study, a 41-item questionnaire was used at the end of the ETAT+ training to evaluate their learning experience from the 12 participants (paediatricians, physicians, nurses and midwives). Six weeks after the training, guided interviews were conducted among five participants to describe how training content could be transferred into clinical practice in five health facilities. Results: Results suggest that this pilot project designed to contribute to the re-establishment of ETAT in Madagascar meets participants' needs and is adapted to clinical realities in terms of transmitted knowledge, skills and competencies. However, results also show that considerable multi-disciplinary efforts are needed to advance ETAT+ implementation in Madagascar. Conclusion: Implementation processes of ETAT training programmes need re-evaluation to assure their validity to contribute to quality of care improvements efficiently. Further operational research is required to evaluate sustainable, innovative implementation strategies adapted to contexts in Madagascar. Contributions of the study: This study aims to evaluate an updated Malagasy version of the Emergency Triage Assessment and Treatment Plus (ETAT+). The training met the participants' needs and was adapted to the clinical realities in Madagascar relating to transmitted knowledge, skills and competencies.

Integrated tuberculosis and HIV care in a resource-limited setting: experience from the Martin Preuss centre, Malawi.

OBJECTIVES: To describe the development and operation of integrated tuberculosis (TB) and HIV care at the Martin Preuss Centre, a multipartner organization bringing together governmental and non-governmental providers of HIV and TB services in Lilongwe, Malawi. METHODS: We used a case study approach to describe the integrated TB/HIV service and to illustrate successes and challenges faced by service providers. We quantified effective TB and HIV integration using indicators defined by the World Health Organization. RESULTS: The custom-designed building facilitates patient flow and infection control, and other important elements include coordinated leadership; joint staff training and meetings; and data systems prompting coordinated care. Some integrated services have worked well from the outset, such as promoting HIV testing among patients with TB (96% of patients with TB had documented HIV status in 2009). Other aspects of integrated care have been more challenging, for example achieving high uptake of antiretroviral therapy among HIV-positive TB patients and combining data from paper and electronic systems. Good TB treatment outcomes (>85% cure or completion) have been achieved among both HIV-positive and HIV-negative individuals. CONCLUSIONS: High-quality integrated services for TB and HIV care can be provided in a resource-limited setting. Lessons learned may be valuable for service providers in other settings of high HIV and TB prevalence.

Second-line treatment in the Malawi antiretroviral programme: high early mortality, but good outcomes in survivors, despite extensive drug resistance at baseline.

OBJECTIVES: The Malawi antiretroviral therapy (ART) programme uses the public health approach to identify ART failure. Advanced disease progression may occur before switching to second-line ART. We report outcomes for patients evaluated and initiated on second-line treatment in Malawi. METHODS: Patients meeting Malawi immunological or clinical criteria for ART failure in two large urban ART clinics were evaluated for virological failure (viral load >400 HIV-1 RNA copies/mL) and, if failure was confirmed, initiated on second-line ART (zidovudine/lamivudine/tenofovir/lopinavir/ritonavir). Patients were seen monthly and laboratory evaluations were performed quarterly and as needed. We performed logistic regression modelling to identify factors associated with mortality, mortality or new HIV illnesses, and virological suppression at 12 months. RESULTS: Of the 109 patients with confirmed virological failure, five patients died prior to initiation, three declined switching and 101 patients initiated second-line treatment. Over 12 months, 10 additional patients died, 34 patients experienced 45 HIV-related events, and 19 patients experienced grade 3 or 4 toxicities. Among survivors, 85.2% had HIV-1 RNA<400 copies/mL at 12 months. While power to distinguish differences was limited, response rates were similar regardless of baseline resistance level. The median CD4 count increase was 142 cells/microL. World Health Organization clinical failure at baseline [odds ratio (OR) 3.47; 95% confidence interval (CI) 1.14-10.59] and body mass index <18.5 (OR 4.43; 95% CI 1.15-17.12) were risk factors for death. Baseline CD4 count <50 cells/microL was associated with increased risk for death or morbidity at 12 months (OR 2.57; 95% CI 1.01-6.52). CONCLUSIONS: Second-line treatment in Malawi was associated with substantial mortality, morbidity and toxicity but, among survivors, virological outcomes were favourable.

Peripheral neuropathy in HIV-positive patients at an antiretroviral clinic in Lilongwe, Malawi.

Peripheral neuropathy (PN) is common in the setting of antiretroviral (ARV) programmes in resource-limited settings and poses significant challenges in assessment and management. A retrospective analysis was undertaken of prevalence and management of PN in a cohort of 3341 patients on highly active antiretroviral therapy. A first line ARV regimen containing stavudine (D4T) is used for clinically eligible patients. Amitriptyline is prescribed for symptom relief and in cases of persistent or escalating symptoms zidovudine (AZT) is substituted for D4T. Leg pain or numbness was reported in 1173 patients (35%). However, only 428 (13%) were given a diagnosis of PN, 228 (7%) were prescribed amitriptyline and 200 (6%) were switched to AZT. A recent pharmokinetic study in this population showed a high Cmax of D4T with the generic combination triomune (D4T 40 mg). This could account for the high prevalence of PN. The optimum time for switch to a non-D4T containing regimen is unknown.

Health-related quality of life in segmental dystonia is improved by bilateral pallidal stimulation.

In contrast to generalized dystonia, reports on the effectiveness of pallidal stimulation on quality of life in patients with segmental dystonia are sparse to date. In ten patients with idiopathic segmental dystonia we prospectively evaluated the effect of pallidal stimulation on quality of life using the SF-36 questionnaire. Parallel to the improvement of motor scores, total SF-36 scores and physical and mental health subscores improved significantly at follow-up to a mean of 17 months postoperatively. Thus, pallidal stimulation should be recognized as a promising treatment option in patients with segmental dystonia.

Deep brain stimulation for dystonia: outcome at long-term follow-up.

OBJECTIVE: Deep brain stimulation (DBS) has emerged as a useful therapeutic option for patients with insufficient benefit from conservative treatment. METHODS: Nine patients with chronic DBS who suffered from cervical dystonia (4), generalized dystonia (2), hemidystonia (1), paroxysmal dystonia (1) and Meige syndrome (1) were available for formal follow-up at three years postoperatively, and beyond up to 10 years. All patients had undergone pallidal stimulation except one patient with paroxysmal dystonia who underwent thalamic stimulation. RESULTS: Maintained improvement was seen in all patients with pallidal stimulation up to 10 years after surgery except in one patient who had a relative loss of benefit in dystonia ratings but continued to have improved disability scores. After nine years of chronic thalamic stimulation there was a mild loss of efficacy which was regained when the target was changed to the pallidum in the patient with paroxysmal dystonia. There were no major complications related to surgery or to chronic stimulation. Pacemakers had to be replaced within 1.5 to 2 years, in general. CONCLUSION: DBS maintains marked long-term symptomatic and functional improvement in the majority of patients with dystonia.

A novel HER2 gene body enhancer contributes to HER2 expression.

The transcriptional regulation of the human epidermal growth factor receptor-2 (HER2) contributes to an enhanced HER2 expression in HER2-positive breast cancers with HER2 gene amplification and HER2-low or HER2-negative breast cancers following radiotherapy or endocrine therapy, and this drives tumorigenesis and the resistance to therapy. Epigenetic mechanisms are critical for transcription regulation, however, such mechanisms in the transcription regulation of HER2 are limited to the involvement of tri-methylated histone 3 lysine 4 (H3K4me3) and acetylated histone 3 lysine 9 (H3K9ac) at the HER2 promoter region. Here, we report the identification of a novel enhancer in the HER2 3' gene body, which we have termed HER2 gene body enhancer (HGE). The HGE starts from the 3' end of intron 19 and extends into intron 22, possesses enhancer histone modification marks in specific cells and enhances the transcriptional activity of the HER2 promoters. We also found that TFAP2C, a known regulator of HER2, binds to HGE and is required for its enhancer function and that DNA methylation in the HGE region inhibits the histone modifications characterizing enhancer and is inversely correlated with HER2 expression in breast cancer samples. The identification of this novel enhancer sheds a light on the roles of epigenetic mechanisms in HER2 transcription, in both HER2-positive breast cancer samples and individuals with HER2-low or HER2-negative breast cancers undergoing radiotherapy or endocrine therapy.

AP2alpha alters the transcriptional activity and stability of p53.

AP2alpha and p53 form nuclear complexes that establish a functional partnership, which regulates the expression of certain genes involved in cell growth and metastasis. The growth effects of AP2alpha are mediated through p21WAF1/CIP1 and the ability for AP2alpha to coactivate p21 requires p53. Herein, we have localized the AP2-binding region of p53 to amino acids 305-375. Analysis of 26 distinct p53 alleles established a correlation between AP2alpha binding and transcriptional coactivation. The L350P point mutation was the only nonbinding allele that retained normal transcriptional activity by reporter assay. Although both wild-type and L350P alleles facilitated binding of AP2alpha to the p21 promoter, the L350P allele was significantly reduced in its ability to induce the endogenous p21 gene, demonstrating a striking difference in activity comparing reporter assays with activation of endogenous p53 target genes. Interestingly, expression of AP2 in the absence of radiation repressed p53-mediated induction of p21 and this effect was explained by a reduction in p53 stability induced by AP2alpha overexpression. We conclude that AP2alpha has competing effects on p53 activity through coactivation and decreased stability. These findings may provide a mechanism to account for the discrepancies reported for the association between AP2 and p21 expression in tumor tissue.

Patterns of reoccurrence of segmental dystonia after discontinuation of deep brain stimulation.

The pattern of reoccurrence of symptoms after discontinuation of deep brain stimulation (DBS) has not been systematically studied in dystonia. Eight patients (mean age (SD) 53.8 (14.4) years) with segmental dystonia at a mean follow-up of 11.3 (4.2) months were studied after implantation of bilateral DBS electrodes in the internal globus pallidus using a standard video protocol and clinical rating scales, immediately and at 2 and 4 h after switching off DBS. Dystonic signs returned sequentially, with a rapid worsening of phasic and a slower worsening of tonic dystonic components. In all patients, phasic dystonic features appeared within a few minutes, whereas the tonic elements of dystonia reoccurred with a more variable delay. Differential clinical effects when withdrawing DBS might reflect its influence on different pathophysiological mechanisms in dystonia.

Outcomes of tuberculosis patients who start antiretroviral therapy under routine programme conditions in Malawi.

SETTING: Public sector facilities in Malawi providing antiretroviral therapy (ART) to human immunodeficiency virus (HIV) positive patients, including those with tuberculosis (TB). OBJECTIVES: To compare 6-month and 12-month cohort treatment outcomes of HIV-positive TB patients and HIV-positive non-TB patients treated with ART. DESIGN: Retrospective data collection using ART patient master cards and ART patient registers. RESULTS: Between July and September 2005, 7905 patients started ART, 6967 with a non-TB diagnosis and 938 with a diagnosis of active TB. 6-month cohort outcomes of non-TB and TB patients censored on 31 March 2006 showed significantly more TB patients alive and on ART (77%) compared with non-TB patients (71%) (P < 0.001). Between January and March 2005, 4580 patients started ART, 4179 with a non-TB diagnosis and 401 with a diagnosis of active TB. 12-month cohort outcomes of non-TB and TB patients censored on 31 March 2006 showed significantly more TB patients alive and on ART (74%) compared with non-TB patients (66%) (P < 0.001). Other outcomes of default and transfer out were also significantly less frequent in TB compared with non-TB patients. CONCLUSION: HIV-positive TB patients on ART in Malawi have generally good treatment outcomes, and more patients need to access this HIV treatment.

Transcriptional regulation of estrogen receptor in breast carcinomas.

An important transcriptional regulatory element of the estrogen receptor (ER) gene that binds a protein expressed in ER-positive breast carcinomas has been identified. Using a transient expression assay, we identified a 75-bp region of the 5' untranslated leader of the ER gene which augments expression from the ER promoter. This region contains two binding sites for a protein, estrogen receptor factor 1 (ERF-1), which is expressed in ER-positive breast carcinomas. A concatenated ERF-1 binding site probe identified a 30,000-Da protein. Low-level ERF-1 expression was detected in normal human mammary epithelial cells. Abundant ERF-1 expression was also found in endometrial carcinoma cell lines that express the ER-positive phenotype. These results indicate that ERF-1 expression represents a common mechanism of ER regulation in hormonally responsive carcinomas.

Adenovirus E1A-mediated negative control of genes activated during F9 differentiation.

The phenotype of a differentiated cell results from the expression of a unique set of genes in that cell. The differentiation of F9 teratocarcinoma cells in response to retinoic acid and cyclic AMP is an excellent example of this process, as the appearance of several gene products during the course of the differentiation process has been documented. In principle, the activation of gene expression could be due to the appearance of positive-acting factors, the loss of negative-acting factors, or a combination of both. Since F9 cells have been shown to express a cellular E1A analog whereas differentiated F9 cells do not, and it is known that the viral E1A gene exerts a negative effect on transcription of both viral and cellular genes, we determined whether the cellular genes activated during F9 cell differentiation are subject to E1A negative control. We found that infection of differentiated F9 cells with wild-type adenovirus resulted in a decline in the levels of collagen type IV mRNA and plasminogen activator mRNA, both of which are induced by differentiation. At least for the collagen gene, this phenomenon appears to involve a transcriptional repression.

Extracellular matrix 1 (ECM1) regulates the actin cytoskeletal architecture of aggressive breast cancer cells in part via S100A4 and Rho-family GTPases.

ECM1 overexpression is an independent predictor of poor prognosis in primary breast carcinomas, however the mechanisms by which ECM1 affects tumor progression have not been completely elucidated. ECM1 was silenced in the triple-negative breast cancer cell lines Hs578T and MDAMB231 using siRNA and the cells were evaluated for changes in morphology, migration, invasion and adhesion. Actin cytoskeleton alterations were evaluated by fluorescent staining and levels of activated Rho GTPases by pull down assays. ECM1 downregulation led to significantly diminished cell migration (p = 0.0005 for Hs578T and p = 0.02 for MDAMB231) and cell adhesion (p < 0.001 for Hs578T and p = 0.01 for MDAMB231). Cell invasion (matrigel) was reduced only in the Hs578T cells (p < 0.01). Silencing decreased the expression of the prometastatic molecules S100A4 and TGFßR2 in both cell lines and CD44 in Hs578T cells. ECM1-silenced cells also exhibited alterations in cell shape and showed bundles of F-actin across the cell (stress fibers) whereas NT-siRNA treated cells showed peripheral membrane ruffling. Downregulation of ECM1 was also associated with an increased F/G actin ratio, when compared to the cells transfected with NT siRNA (p < 0.001 for Hs578T and p < 0.00035 for MDAMB231) and a concomitant decline of activated Rho A in the Hs578T cells. Re-expression of S100A4 in ECM1-silenced cells rescued the phenotype in the Hs578T cells but not the MDAMB231 cells. We conclude that ECM1 is a key player in the metastatic process and regulates the actin cytoskeletal architecture of aggressive breast cancer cells at least in part via alterations in S100A4 and Rho A.

Chronic spinal cord stimulation in medically intractable orthostatic tremor.

BACKGROUND: Orthostatic tremor with its sense of unsteadiness when standing may have a devastating effect on affected persons. Currently, there are no other treatment options in those who do not respond or who do not tolerate medical treatment. OBJECTIVES: To report on a pilot study on spinal cord stimulation in medically intractable orthostatic tremor. METHODS: Chronic spinal cord stimulation (SCS) was performed in two patients with medically-intractable orthostatic tremor via quadripolar plate electrodes implanted at the lower thoracic spine. The electrodes were connected to implantable pulse generators. RESULTS: Subjective and objective improvement of unsteadiness was achieved within a frequency range of 50 to 150 Hz, and occurred in the presence of stimulation-induced paraesthesia. With optimized stimulation settings polygraphic electromyelogram (EMG) recordings continued to show the typical 14-16 Hz EMG activity. The beneficial effect of SCS was maintained at long-term follow-up. CONCLUSIONS: The results of this pilot study indicate that SCS may be an option in patients with otherwise intractable orthostatic tremor.

AP2alpha and AP2gamma: a comparison of binding site specificity and trans-activation of the estrogen receptor promoter and single site promoter constructs.

The AP2 transcription factors exhibit a high degree of homology in the DNA binding and dimerization domains. In this study, we methodically compared the binding specificity of AP2alpha and AP2gamma using PCR-assisted binding site selection and competitive gel shift assay and determined that the consensus binding site for both factors is(G)/(C)CCNN(A/)C(/G)(G)/(A)G(G/)C(/T.)The use of single site promoter constructs with either a high or low affinity site demonstrated a direct relationship between site affinity and transcriptional activation. Overexpression of AP2alpha and AP2gamma resulted in the activation of a low affinity binding site construct to levels comparable to those seen with a high affinity site construct at lower amounts of protein expression. Both AP2alpha and AP2gamma were able to trans-activate the cloned human estrogen receptor alpha promoter in ER-negative MDA-MB-231 cells through high affinity AP2 sites in the untranslated leader sequence. This provides a functional mechanism to explain the correlation between AP2 activity and estrogen receptor expression in breast cancer. Since there is overexpression of AP2 factors in breast cancer compared to normal breast epithelium, our results suggest that increased factor expression may activate a set of target genes containing lower affinity binding sites that would normally not be expressed in normal breast epithelium.