Plant-based nanoparticles targeting malaria management.

Malaria is one of the most devastating diseases across the globe, particularly in low-income countries in Sub-Saharan Africa. The increasing incidence of malaria morbidity is mainly due to the shortcomings of preventative measures such as the lack of vaccines and inappropriate control over the parasite vector. Additionally, high mortality rates arise from therapeutic failures due to poor patient adherence and drug resistance development. Although the causative pathogen (Plasmodium spp.) is an intracellular parasite, the recommended antimalarial drugs show large volumes of distribution and low-to no-specificity towards the host cell. This leads to severe side effects that hamper patient compliance and promote the emergence of drug-resistant strains. Recent research efforts are promising to enable the discovery of new antimalarial agents; however, the lack of efficient means to achieve targeted delivery remains a concern, given the risk of further resistance development. New strategies based on green nanotechnologies are a promising avenue for malaria management due to their potential to eliminate malaria vectors (Anopheles sp.) and to encapsulate existing and emerging antimalarial agents and deliver them to different target sites. In this review we summarized studies on the use of plant-derived nanoparticles as cost-effective preventative measures against malaria parasites, starting from the vector stage. We also reviewed plant-based nanoengineering strategies to target malaria parasites, and further discussed the site-specific delivery of natural products using ligand-decorated nanoparticles that act through receptors on the host cells or malaria parasites. The exploration of traditionally established plant medicines, surface-engineered nanoparticles and the molecular targets of parasite/host cells may provide valuable insights for future discovery of antimalarial drugs and open new avenues for advancing science toward the goal of malaria eradication.

Exploring association between MBL2 gene polymorphisms and the occurrence of clinical blackwater fever through a case-control study in Congolese children.

BACKGROUND: Blackwater fever (BWF), one of the most severe and life-threatening forms of falciparum malaria, is characterized by acute massive intravascular haemolysis, often leading to acute renal failure. Thus far, the genetics of the underlying susceptibility to develop BWF is not fully elucidated. Deficiency in the MBL protein, an important component of the innate immune system, has previously been suggested to be a susceptibility factor for the development of severe malaria. This study aimed to evaluate the association between MBL2 gene polymorphisms, known to affect the MBL protein level/activity, and the occurrence of BWF among Congolese children. METHODS: This is a case-control study. Cases were patients with BWF, whereas controls, matched for gender and age, had uncomplicated malaria (UM). Dried blood spot was collected for genotyping. RESULTS: A total of 129 children were screened, including 43 BWF and 86 UM. The common allele in BWF and UM was A, with a frequency of 76.7 and 61.0%, respectively (OR: 2.67 (0.87-829) and p = 0.079). The frequency of the C allele was 18.6 and 29.1% in BWF and UM groups, respectively, with p = 0.858. Not a single D allele was encountered. Genotype AA was at higher risk for BWF whereas genotypes A0 (AB and AC) were over-represented in UM group (OR: 0.21 (0.06-0.78)) with p = 0.019. Nine haplotypes were observed in this study: 3 high MBL expression haplotypes and 6 low MBL expression haplotype. One new haplotype HYPC was observed in this study. None of these haplotypes was significantly associated with BWF. CONCLUSION: This pilot study is a preliminary research on MBL2 gene and infectious diseases in DRC. The study results show a higher risk for BWF in AA. This suggests that future studies on BWF should further investigate the contribution of a strong immune response to the occurrence of BWF.

Protein phase separation and determinants of in cell crystallization.

Liquid-liquid phase separation (LLPS) in cells is known as a complex physicochemical process causing the formation of membrane-less organelles (MLOs). Cells have well-defined different membrane-surrounded organelles like mitochondria, endoplasmic reticulum, lysosomes, peroxisomes, etc., however, on demand they can create MLOs as stress granules, nucleoli and P bodies to cover vital functions and regulatory activities. However, the mechanism of intracellular molecule assembly into functional compartments within a living cell remains till now not fully understood. in vitro and in vivo investigations unveiled that MLOs emerge after preceding liquid-liquid, liquid-gel, liquid-semi-crystalline, or liquid-crystalline phase separations. Liquid-liquid and liquid-gel MLOs form the majority of cellular phase separation events, while the occurrence of micro-sized crystals in cells was only rarely observed, however can be considered as a result of a preceding protein phase separation event. In vivo, also known and termed as in cellulo crystals, are reported since 1853. In some cases, they have been linked to vital cellular functions, such as storage and detoxification. However, the occurrence of in cellulo crystals is also associated to diseases like cataract, hemoglobin C diseases, etc. Therefore, better knowledge about the involved molecular processes will support drug discovery investigations to cure diseases related to in cellulo crystallization. We summarize physical and chemical determinants known today required for phase separation initiation and formation and in cellulo crystal growth. In recent years it has been demonstrated that LLPS plays a crucial role in cell compartmentalization and formation of MLOs. Here we discuss potential mechanisms and potential crowding agents involved in protein phase separation and in cellulo crystallization.

Drug use in the management of uncomplicated malaria in public health facilities in the Democratic Republic of the Congo.

BACKGROUND: Malaria the first causes of death from parasitic infection worldwide. Interventions to reduce the burden of malaria have produced a tremendous drop in malaria morbidity and mortality. However, progress is slower in DRC, which shares with Nigeria 39% of deaths related to malaria globally. Inappropriate use of drugs may be one of the factors of this below-average performance. The aim of this study was to describe the use of drugs in the management of uncomplicated malaria in public health facilities in DRC. METHODS: A drug use study was carried out in DRC from January to March 2014. In each of the former 11 provinces of DRC, one Rural Health Centre, one Urban Health Centre and one General Hospital were selected. In each of them, 100 patient's files containing prescription of anti-malarials from January to December 2013 were randomly selected. Among them, all of the files with diagnosis of uncomplicated malaria were included in this study. Prescribed anti-malarials, co-prescribed drugs and their indications were collected. Descriptive analyses were performed. RESULTS: A total of 2300 files out of 3300 (69.7%) concerned uncomplicated malaria and were included in analysis. Malaria treatment was initiated after a positive RDT or microscopy in 51.5% of cases, upon suspicion without requesting biological confirmation in 37% and despite negative results in 11%. Twenty-nine (29) different treatment regimens were used. The drugs recommended by the National Malaria Control Programme were used in 54.3% of cases (artesunate-amodiaquine 37.4% or artemether-lumefantrine 16.9%). The second most used anti-malarial was quinine (32.4%). Apart from anti-malarials, an average of 3.1 drugs per patient were prescribed, among which antibiotics (67.9%), analgesics and non-steroidal anti-inflammatory (NSAIDs) (all abbreviations to be explicated on first use) (70.6%), vitamins (29.1%), anaemia drugs, including blood transfusion (9.1%) and corticosteroids (5.7%), In 51.4% of cases there was no indication for the concomitant medication. CONCLUSION: Management of uncomplicated malaria in DRC is characterized by a low adherence to treatment policy, numerous treatment regimens, and abundant concomitant medication potentially harmful to the patient. This may contribute to the low performance of DRC in malaria control. Determinant of this irrational use of drugs need to be assessed in order to formulate and implement efficient corrective measures.

Success factors for implementing and sustaining a mature electronic medical record in a low-resource setting: a case study of iSanté in Haiti.

Electronic health information systems, including electronic medical records (EMRs), have the potential to improve access to information and quality of care, among other things. Success factors and challenges for novel EMR implementations in low-resource settings have increasingly been studied, although less is known about maturing systems and sustainability. One systematic review identified seven categories of implementation success factors: ethical, financial, functionality, organizational, political, technical and training. This case study applies this framework to iSanté, Haiti's national EMR in use in more than 100 sites and housing records for more than 750 000 patients. The author group, consisting of representatives of different agencies within the Haitian Ministry of Health (MSPP), funding partner the Centers for Disease Control and Prevention (CDC) Haiti, and implementing partner the International Training and Education Center for Health (I-TECH), identify successes and lessons learned according to the seven identified categories, and propose an additional cross-cutting category, sustainability. Factors important for long-term implementation success of complex information systems are balancing investments in hardware and software infrastructure upkeep, user capacity and data quality control; designing and building a system within the context of the greater eHealth ecosystem with a plan for interoperability and data exchange; establishing system governance and strong leadership to support local system ownership and planning for system financing to ensure sustainability. Lessons learned from 10 years of implementation of the iSanté EMR system are relevant to sustainability of a full range of increasingly interrelated information systems (e.g. for laboratory, supply chain, pharmacy and human resources) in the health sector in low-resource settings.

Prevalence and determinants of microalbuminuria in children suffering from sickle cell anemia in steady state.

BACKGROUND: Sickle cell anemia (SCA) is considered a major risk factor for renal complications. The main goal of this study was to determine the frequency of macroalbuminuria and microalbuminuria in Congolese children <18 years of age suffering from Sickle cell anemia and to identify associated factors. METHODS: The cross-sectional study was completed in 150 hemoglobin-SS children (77 boys and 73 girls). Microalbuminuria was defined by a urine albumin:creatinine ratio of 30-299 mg/g. RESULTS: The mean age of this group was 8.8 ± 4.3 years (range 2-18). Microalbuminuria was found in 27 children (18%). In multivariate logistic regression, only age emerged as a determinant of microalbuminuria odds ratio 1.11 (95% confidence interval 1.00-1.22); P = 0.042]. CONCLUSIONS: In our series, only age was a major determinant of the occurrence of microalbuminuria. These results confirm the need for early screening of microalbuminuria in Congolese children suffering from Sickle cell anemia in a context where access to renal and bone marrow transplant is nonexistent.

African trypanosomes and brain infection - the unsolved question.

African trypanosomes induce sleeping sickness. The parasites are transmitted during the blood meal of a tsetse fly and appear primarily in blood and lymph vessels, before they enter the central nervous system. During the latter stage, trypanosomes induce a deregulation of sleep-wake cycles and some additional neurological disorders. Historically, it was assumed that trypanosomes cross the blood-brain barrier and settle somewhere between the brain cells. The brain, however, is a strictly controlled and immune-privileged area that is completely surrounded by a dense barrier that covers the blood vessels: this is the blood-brain barrier. It is known that some immune cells are able to cross this barrier, but this requires a sophisticated mechanism and highly specific cell-cell interactions that have not been observed for trypanosomes within the mammalian host. Interestingly, trypanosomes injected directly into the brain parenchyma did not induce an infection. Likewise, after an intraperitoneal infection of rats, Trypanosoma brucei brucei was not observed within the brain, but appeared readily within the cerebrospinal fluid (CSF) and the meninges. Therefore, the parasite did not cross the blood-brain barrier, but the blood-CSF barrier, which is formed by the choroid plexus, i.e. the part of the ventricles where CSF is produced from blood. While there is no question that trypanosomes are able to invade the brain to induce a deadly encephalopathy, controversy exists about the pathway involved. This review lists experimental results that support crossing of the blood-brain barrier and of the blood-CSF barrier and discuss the implications that either pathway would have on infection progress and on the survival strategy of the parasite. For reasons discussed below, we prefer the latter pathway and suggest the existence of an additional distinct meningeal stage, from which trypanosomes could invade the brain via the Virchow-Robin space thereby bypassing the blood-brain barrier. We also consider healthy carriers, i.e. people living symptomless with the disease for up to several decades, and discuss implications the proposed meningeal stage would have for new anti-trypanosomal drug development. Considering the re-infection of blood, a process called relapse, we discuss the likely involvement of the newly described glymphatic connection between the meningeal space and the lymphatic system, that seems also be important for other infectious diseases.

Presence of species within the Anopheles gambiae complex in the Democratic Republic of Congo.

BACKGROUND: Anopheles gambiae s.l. is the primary vector of malaria in the Democratic Republic of Congo, however, there is little data on the species from this complex present in the country. METHODS: This paper presents the species collected (as determined by PCR) between 2004 and 2011 in 16 locations across the country. RESULTS AND CONCLUSIONS: The two species from the An. gambiae complex that were detected were An. coluzzii and An. gambiae s.s. An. gambiae s.s. was predominant in eastern DRC, whereas An. coluzzii was the main species found in several locations in Bandundu. The species were also found in sympatry in several locations (Kinshasa, Kisangani, Lodja). These results provide a basis for future work, which is needed to accurately describe the distribution of the An. gambiae complex species in DRC.

Falciparum malaria molecular drug resistance in the Democratic Republic of Congo: a systematic review.

BACKGROUND: Malaria cases were estimated to 207 million in 2013. One of the problems of malaria control is the emergence and spread of Plasmodium falciparum strains that become resistant to almost all drugs available. Monitoring drug resistance is essential for early detection and subsequent prevention of the spread of drug resistance by timely changes of treatment policy. This review was performed to gather all data available on P. falciparum molecular resistance in DR Congo, as baseline for future assessments. METHODS: The search for this review was undertaken using the electronic databases PubMed and Google Scholar using the terms "malaria", "Congo", "resistance", "molecular", "antimalarial", "efficacy". Articles were classified based on year of collecting, year of publication, sample size and characteristics, molecular markers analysed and polymorphisms detected. RESULTS: Thirteen articles were included and five genes have been analysed in these studies: pfcrt, pfdhps, pfdhfr, pfmdr1 and K13-propeller. The majority of studies included were not representative of the whole country. CONCLUSION: This systematic review demonstrates the lack of molecular resistance studies in DRC. Only 13 studies were identified in almost 15 years. The MOH must implement a national surveillance system for monitoring malaria drug resistance and this surveillance should be conducted frequently and country-representative.

Severe malaria in children: A descriptive report from Kinshasa, the Democratic Republic of Congo.

The decline of susceptibility of Plasmodium falciparum to chloroquine and sulfadoxine-pyrimethamine resulted in the change of drug policy. This policy has probably changed the facies of the severe form of malaria. A prospective study was conducted in Kinshasa, the Democratic Republic of Congo. Data on children aged ≤13 years, diagnosed with severe malaria were analyzed. In total, 378 children were included with an overall median age of 8 years (age range: 1-13 years). Dark urine was seen in 25.1% of cases. Metabolic acidosis (85.2%), hypoglycemia (62.2%) and hemoglobin ≤5 g/dl (39.1%) were the common laboratories features. Severe malaria anemia, cerebral malaria and Blackwater fever (BWF) were found in 39.1, 30.1 and 25.4%, respectively. Mortality rate was 4%. BWF emerges as a frequent form of severe malaria in our midst. Availing artemisin-based combination treatments in the health care system is a priority to reduce the incidence of BWF in our environment.

Malaria epidemic outbreaks in the Democratic Republic of Congo, part I: cross-sectional survey in Mweka District.

Background: A series of outbreaks of fever has previously been reported in the DR Congo. The occurrence of similar outbreaks in Mweka district presented the opportunity to investigate these occurrences. Materials and Methods: Health facilities and communities were visited. Permission was obtained to access to health records and a questionnaire was competed in the community. Blood samples for malaria, salmonellosis, Chikungunya, dengue and filovirus testing were obtained both in health facilities and the communities. Capture of mosquitoes and larvae in breeding sites was done and used bednets were collected. Excel, SPSS and Stats Direct were used for analyses of epidemiological data and malaria case management, with the Chi-square test and Fisher's Exact test used for assessing relationships resulting from contingency table analyses. Results: An increase in the number of malaria cases beyond the expected number for the study period was observed in the two health districts located in the savannah zone (p<0.05) and in one health centre among sixteen located in the forest zone (p<0.05). In the health facilities and households visited (653 people), 141 persons had fever of which 82.2% was attributed to Plasmodium falciparum malaria. An incidence of 5.87% was recorded in the first half of 2013. Hundred and sixty patients (6.9%) died among 2,304 admitted for severe malaria in the three referral hospitals, 118 of them were children of under five years old. PCR testing of the blood samples obtained during home visits revealed malaria parasites in 63 (73.3%) of the 86 analysed samples. The test was negative for other parasites and bacteria and one dengue virus case was detected. Anopheles gambiae from Mweka were found to be resistant to permethrin using the WHO susceptibility test, with a knock down rate of ≤ 50% and mortality of ≤ 30%. Conclusion: These investigations confirmed epidemic outbreaks in Mweka District caused by malaria with a high mortality rate in children below five years of age.

Black water fever associated with acute renal failure among Congolese children in Kinshasa.

Acute renal failure (ARF) is reported in some severe forms of malaria such as black water fever (BWF). It is associated with a high mortality rate and can be managed effectively with adequate renal replacement. A prospective survey of children with dark urine after a malarial infection with Plasmodium falciparum was coupled with a chart review study of patients managed in the past 11 years in the Pediatrics' Kinshasa University Hospital. Eighty-nine cases of ARF were identified, but data from only 63 patients were available, of whom 44 (69.8%) had severe malaria (39 with BWF and 5 with cerebral malaria). The mean age of the patients was 8.2±1.73 years. Of the 39 cases of BWF, an association with quinine ingestion was observed in 32 children (82%). Urea and creatinine levels were elevated in all cases (135.4±88.2 and 3.83±2.81 mg/dL, respectively). Oligo-anuria was observed in 44.4%, severe metabolic acidosis (bicarbonate<15 mEq/L) in 61.5% and hyponatremia (<130 mEq/L) in 33.3%. Peritoneal dialysis was required in 36 patients, including 20 with BWF. The remaining patients were managed with conservative treatment. Twenty-eight children (44.4%), including 20 on dialysis, fully recovered and 14 died (22.2%), including eight cases of BWF. Our study suggests that ARF is commonly associated with BWF in Congolese children. Elevated urea and creatinine and severe metabolic acidosis were observed more often than other clinical/metabolic disturbances. Severe renal impairment remains a significant complication with a high mortality rate in low-resource settings.

Blackwater fever in Congolese children: a report of clinical, laboratory features and risk factors.

BACKGROUND: Blackwater fever (BWF) is one of the severe forms of malaria. This complication was first described among non-immune European expatriates in the malaria endemic areas. Recently, resurgence of this form of malaria has been reported among the indigenous populations. The objective of this study was to investigate the risk factors among BWF patients. METHODS: A case-control study was conducted between in four hospitals located in Kinshasa, Democratic Republic of Congo from January 2010 to December 2011. One hundred and twenty nine children were recruited with 43 (cases) and 86 (control). RESULTS: No significant difference in the gender and age distribution was observed between the case and control). The sex-ratio male to female in the case group and control group was respectively 1:1.0 and 1:1.1. The mean age was 8.62 years (SD = 3.84) in patients with haemoglobinuria and 8.55 years (SD = 3.77) in the control group. No difference in frequency of co-infection with Plasmodium falciparum and Plasmodium malariae was observed between the two groups. Significant differences in haemoglobin, haematocrit, creatinine, urea and platelets levels were observed between the two groups (p < 0.001), but not for blood group and lactate dehydrogenase (LDH) level. Majority of the BWF cases occurred during the rainy season (88.4%). Treatment with quinine (95.3%) was significantly associated with cases (p < 0.001). Seven (16.2%) of the haemoglobinuric children developed acute renal failure. CONCLUSION: Rainy season, low parasitaemia and quinine ingestion were the major risk factors significantly associated with haemoglobinuria. Acute renal failure was observed as the major complication of BWF.

Acute renal failure in Congolese children: a tertiary institution experience.

AIM: Published data on acute renal failure in children from the Democratic Republic of Congo are rare. The objective of this study was to review clinical manifestations, aetiologies and outcome in hospitalized children with acute renal failure. METHODS: A retrospective study at Pediatric Nephrology Unit of University Hospital of Kinshasa was carried out. RESULTS: Fifty-six children with acute renal failure were eligible. There were 31 boys (55.4%) and 25 girls (44.6%) with a sex ratio of 1.24. The median age was 6.7 years (range 1-13 years). Fever (80.3%), oligo-anuria (73.2%), jaundice (67.9%) were the common clinical presentation. Blackwater fever (42.8%) was the leading cause of Acute Renal Failure. The incidence of severe dehydration because of gastroenteritis was low (5.3%). Around 12.5% of patients' misused herbal plants. Acute Peritoneal Dialysis was indicated in 15/56 children and only performed in four patients. Fourteen children (25%) died. CONCLUSION: A wide spectrum of features was seen in hospitalized Acute Renal Failure children and limited access to Acute Peritoneal Dialysis remained an important mortality risk factor.