The dynamics of adult neurogenesis in human hippocampus

The phenomenon of adult neurogenesis is now an accepted occurrence in mammals and also in humans. At least two discrete places house stem cells for generation of neurons in adult brain. These are olfactory system and the hippocampus. In animals, newly generated neurons have been directly or indirectly demonstrated to generate a significant amount of new neurons to have a functional role. However, the data in humans on the extent of this process is still scanty and such as difficult to comprehend its functional role in humans. This paper explores the available data on as extent of adult hippocampal neurogenesis in humans and makes comparison to animal data

Characterising cancer burden and quality of care at two palliative care clinics in Malawi

Background: This paper describes cancer burden and compares characteristics of cancer patients enrolled at 2 palliative care facilities of contrasting resources and geographical locations in Malawi. It also assesses the extent of differences in service delivery and the impact these might have on outcomes.Methods: Data on all cancer patients registered between October 2010 and October 2015 at Tiyanjane Clinic (at Queen Elizabeth Central Hospital, Blantyre) and Mzuzu Central Hospital (MCH) palliative care clinics were extracted and analysed. Key informant in-depth interviews were carried out at both sites. Thematic analysis was used for qualitative data and Excel 2010 and Stata 12 were used for analysis of quantitative data.Results: Quantitative: There were 1362 and 633 cancer patients at Tiyanjane and MCH, respectively. Overall, females predominated over males (55.8% vs 42.8%); however, Tiyanjane had more males (52.2% vs 45.8%), which was contrary to Mzuzu (77.4% females vs 22.6% males). The 35- to 54-year age group was predominant at both Tiyanjane (43.1%) and Mzuzu (40.1%). Overall, the most common cancers were Kaposi’s sarcoma (26.9%), cervical cancer (26.8%), oesophageal cancer (14.2%), hepatocellular carcinoma (4.9%), and bladder cancer (3.0%). Histologically confirmed diagnoses accounted for 13% of cases at Tiyanjane, whereas all patients from MCH were diagnosed clinically.Qualitative: Palliative care services were free of charge at both facilities, and owing to the expansion of services to district hospitals, the workload at central hospitals had been reduced. Between the 2 sites, there were differences in follow-up procedures, drug availabilities, as well as human resource capacity, with Mzuzu palliative care facility facing more extensive challenges.Conclusions: The characteristics of patients seen at each site varied according to services available. Quality of care was assessed as superior at Tiyanjane, demonstrating the importance of multiple stakeholder involvement in the delivery of palliative care services

ABO blood group phenotypes influence parity specific immunity to Plasmodium falciparum malaria in Malawian women

Background: Blood group O has been significantly associated with increased placental malaria infection in primiparae and reduced risk of infection in multiparae in the Gambia, an area with markedly seasonal malaria transmission. This study analyses the association between ABO blood group phenotypes in relation to placental malaria pathology and birth outcomes in southern Malawi, an area with perennial malaria transmission. Methods: A cross- sectional study of 647 mother/ child pairs delivering in Montfort Hospital, Chikwawa District between February- June 2004 and January- July 2005 was undertaken. Maternal peripheral and cord blood samples were obtained at delivery. Placental tissue was obtained and malaria histology classified as active, past or no malaria infection. Birth anthropometry was recorded. ABO blood group was measured by agglutination. Results: In primiparae, blood group O was significantly associated with increased risk of active placental infection ( OR 2.18, 95% CI 1.15 - 4.6, p = 0.02) and an increased foetal- placental weight ratio compared to non- O phenotypes ( 5.68 versus 5.45, p = 0.03) In multiparae blood group O was significantly associated with less frequent active placental infection ( OR 0.59, 95% CI 0.36 - 0.98, p = 0.04), and a higher newborn ponderal index compared to non- O phenotypes ( 2.65 versus 2.55, p = 0.007). In multivariate regression parity was independently associated with increased risk of placental malaria ( active andpast infection) in primiparae with blood group O ( p = 0.034) and reduced risk in multiparae with the same phenotype ( p = 0.015). Conclusion: Parity related susceptibility to placental malaria is associated with the mothers ABO phenotype. This interaction influences foetal and placental growth and could be an important modifying factor for pregnancy outcomes. The biological explanation could relate to sialic acid dependent placental membrane differences which vary with ABO blood group

The systemic pathology of cerebral malaria in African children

Pediatric cerebral malaria carries a high mortality rate in sub-Saharan Africa. We present our systematic analysis of the descriptive and quantitative histopathology of all organs sampled from a series of 103 autopsies performed between 1996 and 2010 in Blantyre, Malawi on pediatric cerebral malaria patients and control patients (without coma, or without malaria infection) who were clinically well characterized prior to death. We found brain swelling in all cerebral malaria patients and the majority of controls. The histopathology in patients with sequestration of parasites in the brain demonstrated two patterns: (a) the “classic” appearance (i.e., ring hemorrhages, dense sequestration, and extra-erythrocytic pigment) which was associated with evidence of systemic activation of coagulation and (b) the “sequestration only” appearance associated with shorter duration of illness and higher total burden of parasites in all organs including the spleen. Sequestration of parasites was most intense in the gastrointestinal tract in all parasitemic patients (those with cerebral malarial and those without)

High Cancer Burden Among Antiretroviral Therapy Users in Malawi: a Record Linkage Study of Observational HIV Cohorts and Cancer Registry Data.

Background With antiretroviral therapy (ART), AIDS-defining cancer incidence has declined and non-AIDS defining cancers are now more frequent among HIV-infected populations in high-income countries. In sub-Saharan Africa, limited epidemiological data describe cancer burden among ART users. Methods We used probabilistic algorithms to link cases from the population-based cancer registry with electronic medical records supporting ART delivery in the Malawi's two largest HIV cohorts, Lighthouse Trust (LT; 2007-2010) and Queen Elizabeth Central Hospital (QECH; 2000-2010). Age-adjusted cancer incidence rates (IR) and 95% confidence intervals were estimated by cancer site, early versus late incidence periods (4 -24 and >24 months after ART start), and WHO stage among naïve ART initiators enrolled for at least 90 days. Results We identified 4,346 cancers among 28,576 persons. Most people initiated ART at advanced WHO stage (LT stage 3/4: 55%; QECH stage 3/4: 66%); 12% of patients had prevalent malignancies at ART initiation, which were predominantly AIDS-defining eligibility criteria for initiating ART. Kaposi sarcoma (KS) had the highest IR (634.7 per 100,000 person-years), followed by cervical cancer (36.6). KS incidence was highest during the early period 4-24 months after ART initiation. Non-AIDS defining cancers (NADC) accounted for 6% of new cancers. Conclusions Under historical ART guidelines, NADC were observed at low rates, and were eclipsed by high KS and cervical cancer burden. Cancer burden among Malawian ART users does not yet mirror high-income countries. Integrated cancer screening and management in HIV clinics, especially for KS and cervical cancer, remain important priorities in the current Malawi context

Distribution of variations in anatomy of the circle of Willis: results of a cadaveric study of the Malawian population and review of literature

Introduction the circle of Willis is an anatomical structure of clinical importance particularly in the evaluation of neurovascular diseases. Individuals show considerable variations in the anatomical configuration of the circle of Willis. A cross-sectional study was conducted to determine the distribution of morphological variations of the circle of Willis in Malawians and compare with other ethnic groups. Methods brains were collected from twenty-four recently deceased black Malawians during autopsy at Queen Elizabeth Central Hospital, a referral teaching hospital in Blantyre, Malawi and fixed in 10% buffered formalin. Digital images of the interpeduncular region (exposing the circle of Willis) were taken with an 18.4 megapixels camera from the base of the brain. Whole-circle and segmental parameters of the circle of Willis were assessed using the Osiris computer programme and classified based on a 22-type classification scheme. Results the following morphological variations were observed: hypoplasia, aplasia, asymmetry and accessory vessels. Typical circle of Willis was seen in 26% of the cases. Only six of the original twenty-two types were observed. Consistent with most previous studies, types 1, 3, 4, 6, 8 and 9 were common while types 10-22 were rare. Three variants not previously described in the original scheme (unilateral PcoA aplasia, AcoA duplication, and PcoA aplasia with contralateral PcoA hypoplasia) were observed in this study. Conclusion anatomical variations of the circle of Willis in Malawians seem to be distributed in similar frequencies and patterns as in other more-diverse populations. Circle of Willis variants with potential predilection for atherogenesis and aneurysm formation exist in the Malawian population. These should be considered in clinical practice

Anatomical variations and morphometric properties of the circulus arteriosus cerebri in a cadaveric Malawian population

Background: Knowledge of the anatomy of the circulus arteriosus cerebri (CAC) is important in understanding its role as an arterial anastomotic structure involved in collateral perfusion and equalisation of pressure, and may explain observed variations in neurovascular disease prevalences across populations. This study was aimed at understanding the anatomical configuration and morphometric properties of the CAC in Malawian population. Materials and methods: Brains were collected from 24 recently-deceased black Malawian human cadavers during medico-legal autopsies. Photographs of the CACs were taken using a camera placed at a 30 cm height from the base of the brain. Whole-circle properties and segmental vessel parameters were analysed using the OSIRIS computer programme, paying attention to completeness, typicality, symmetry, and segmental vessel diameters and lengths. Results: The complete-circle configuration was found in 69.57% of the CACs. Of these, 37.5% were typical, representing an overall typicality prevalence of 26.09%. Vessel asymmetry was observed in 30.43% of cases. There were 7 cases of vessel aplasia and 12 cases of vessel hypoplasia. The posterior communicating artery (PcoA) was the most variable (with 12 variations), widest (7.67 mm) and longest (27.7 mm) vessel while the anterior communicating artery (AcoA) was the shortest (0.78 mm). Both the AcoA and the PcoA were the narrowest vessels (0.67 mm) in this study. CAC variations in Malawian populations appeared to be similar to those observed in diverse populations. Conclusions: Anatomical variations of the CAC exist in Malawian population and should be taken into consideration in clinical practice

Oesophageal cancer and Kaposi’s Sarcoma in Malawi: a comparative analysis

Given that oesophageal cancer (OC) is common in Malawi and its outcome is so dismal, would it be pragmatic to promptly mitigate the effects of smoking, alcohol and aflatoxins rather than seek a higher degree of local evidence for their role in OC? We retrospectively analysed a total of 13,217 OC and Kaposi’s sarcoma (KS) cases as recorded in the Malawi National Cancer Registry from 1985 to February, 2006. We found no OC clustering to suggest a role for culturally variable habits like smoking, alcohol, maize use and maize storage in the country. It may be that drinking and eating hot foods physically damages the oesophageal mucosa, this is in line with work recently reported from Asia. We also found that OC numbers have risen in line with KS (and HIV) suggesting a link between these conditions

Burden of cancer in Malawi; common types, incidence and trends: National population-based cancer registry

Abstract Background Cancer is a leading cause of morbidity and mortality worldwide with a majority of cases and deaths occurring in developing countries. While cancer of the lung, breast, colorectum, stomach and prostate are the most common types of cancer globally, in east and southern Africa these are less common and comprehensive data to inform policies are lacking. Methods Nationwide cancer registry was conducted between September and October 2010 in Malawi. New cancer cases registered from 2007 to 2010 were identified from hospital and clinic registers of 81 out of 84 health facilities providing cancer diagnosis, treatment or palliative care services. Demographic and cancer data were extracted from registers and case notes using a standard form. Results A total of 18,946 new cases of cancer were registered in Malawi from 2007-2010. Of these 55.9% were females, 7.2% were children aged less than 15 years, 76.5% were adults aged 15-59 years and 16.4% were elderly aged 60 years or more. Only 17.9% of the cases had histologically verified diagnosis, 33.2% were diagnosed clinically and 49.6% based on clinical and some investigations. Amongst females, cancer of the cervix was the commonest accounting for 45.4% of all cases followed by Kaposi sarcoma (21.1%), cancer of the oesophagus (8.2%), breast (4.6%) and non-Hodgkin lymphoma (4.1%). In males, Kaposi sarcoma was the most frequent (50.7%) then cancer of oesophagus (16.9%), non-Hodgkin lymphoma (7.8), prostate (4.0%) and urinary bladder (3.7%). Age-standardised incidence rate per 100,000 population for all types of cancer in males increased from 31 in 1999-2002 to 56 in 2007-2010. In females it increased from 29 to 69. Kaposi sarcoma and cancer of the oesophagus, cervical cancer and Kaposi sarcoma were the main causes for the increased incidence in males and females respectively. It was estimated that, annually at least 8,151 new cases of cancer (all types) occur in Malawi. Conclusions This study provided data on common types and trends of cancer that could be used to focus prevention, treatment and control interventions in the context of limited resources. The problem of under-reporting and misdiagnosis of cancer cases has been highlighted.</p