Application of Morphometric and Stereological Techniques on Analysis and Modelling of the Avian Lung

For a long time, biology was a qualitative (descriptive) science. The investigations failed to fully explicate the functional designs of whole organisms and their constituent parts. About half a century ago, at an interdisciplinary meeting which was held in Feldberg (Germany), the International Society of Stereology (ISS) was formed. Mathematicians, statisticians and physical and biological scientists combined their skills to create a new scientific discipline of stereology that allowed for reliable and reproducible quantitation of structural entities of composite physical and biological materials and extrapolation of measurements made on two‐dimensional profiles/images to their three‐dimensional forms. With time, novel bias‐free sampling and quantitation techniques have been developed and tested. Presently, there is no justification for totally descriptive biological studies. Numerous books, publications, computer programmes and applications and dedicated microscopes exist for cost‐effective analysis. Within the relatively short time, it has been in existence, the ISS has actively advanced stereology which is now applied by scientists all over the world in various biological disciplines. Only basic understanding of mathematics, geometry and statistics is needed to do good stereology. Here, analysis of the avian (bird) lung is given to show the versatility and robustness of stereological techniques in analysing biological structures

ANTIINFLAMMATORY PROPERTIES OF DICHLOROMETHANE: METHANOLIC LEAF EXTRACTS OF CAESALPINIA VOLKENSII AND MAYTENUS OBSCURA IN ANIMAL MODELS

Objective: Inflammation is the reaction to injury of the living tissues. Conventional medication of inflammation is expensive and arguably associated with various severe adverse effects hence the need to develop herbal agents that are effective as alternative. Caesalpinia volkensii and Maytenus obscura are plants that grow in Mbeere County of Eastern region of Kenya. This study was designed to evaluate the anti-inflammatory activity of C. volkensii and M. obscura plants. Methods: Experimental animals were divided in to four groups; normal group, diseased negative control group, diseased reference group and diseased experimental groups. Inflammation was inducted into the mice using carrageenan. The experimental groups were treated with leaf extracts of the plants at concentration of 50 mg/kg, 100 mg/kg and 150 mg/kg. Anti-inflammatory activities in rats were compared with diclofenac (15 mg/kg) as the standard conventional drug. Results: The leaf extracts of C. volkensii reduced the paw edema by between 6.50%-13.42% while the extracts of M. obscura reduced it by between 4.94%-22.36%. Diclofenac reduced the paw edema by between 4.11%-10.47%. Conclusion: The phytochemical screening results showed that the extracts of C. volkensii had flavonoids, steroids and phenolics while the leaf extracts M. obscura had phenolics, terpenoids and saponins. Flavonoids, saponins and phenolics have been associated with anti-inflammatory activities. Therefore, the study has established that the DCM: methanolic leaf extracts of Caesalpinia volkensii and Maytenus obscura are effective in management of inflammation

Impact of Plasmodium falciparum infection on haematological parameters in children living in Western Kenya

<p>Abstract</p> <p>Background</p> <p>Malaria is the commonest cause of childhood morbidity in Western Kenya with varied heamatological consequences. The t study sought to elucidate the haemotological changes in children infected with malaria and their impact on improved diagnosis and therapy of childhood malaria.</p> <p>Methods</p> <p>Haematological parameters in 961 children, including 523 malaria-infected and 438 non-malaria infected, living in Kisumu West District, an area of malaria holoendemic transmission in Western Kenya were evaluated.</p> <p>Results</p> <p>The following parameters were significantly lower in malaria-infected children; platelets, lymphocytes, eosinophils, red blood cell count and haemoglobin (Hb), while absolute monocyte and neutrophil counts, and mean platelet volume (MPV) were higher in comparison to non-malaria infected children. Children with platelet counts of <150,000/uL were 13.8 times (odds ratio) more likely to have malaria. Thrombocytopaenia was present in 49% of malaria-infected children and was associated with high parasitaemia levels, lower age, low Hb levels, increased MPV and platelet aggregate flag. Platelet aggregates were more frequent in malaria-infected children (25% vs. 4%, p<0.0001) and associated with thrombocytopaenia rather than malaria status.</p> <p>Conclusion</p> <p>Children infected with <it>Plasmodium falciparum</it> malaria exhibited important changes in some haematological parameters with low platelet count and haemoglobin concentration being the two most important predictors of malaria infection in children in our study area. When used in combination with other clinical and microscopy, these parameters could improve malaria diagnosis in sub-patent cases.</p

<i>Trypanosoma brucei rhodesiense</i> transmitted by a single tsetse fly bite in vervet monkeys as a model of human African trypanosomiasis

Sleeping sickness is caused by a species of trypanosome blood parasite that is transmitted by tsetse flies. To understand better how infection with this parasite leads to disease, we provide here the most detailed description yet of the course of infection and disease onset in vervet monkeys. One infected tsetse fly was allowed to feed on each host individual, and in all cases infections were successful. The characteristics of infection and disease were similar in all hosts, but the rate of progression varied considerably. Parasites were first detected in the blood 4-10 days after infection, showing that migration of parasites from the site of fly bite was very rapid. Anaemia was a key feature of disease, with a reduction in the numbers and average size of red blood cells and associated decline in numbers of platelets and white blood cells. One to six weeks after infection, parasites were observed in the cerebrospinal fluid (CSF), indicating that they had moved from the blood into the brain; this was associated with a white cell infiltration. This study shows that fly-transmitted infection in vervets accurately mimics human disease and provides a robust model to understand better how sleeping sickness develops

Investigation of Prader-Willi-like Phenotype using a Whole Genome Array

IntroductionPrader-Willi syndrome (PWS) is characterised byobesity, short stature, small hands and feet, neonatalhypotonia with difficulty in feeding at birth,hypogonadism and eye problems. At about two years ofage the feeding difficulties with poor suck are graduallyreplaced by hyperphagia and obsession with food,leading to the obesity. In addition to developmentaldelay which is manifested by short stature, small handsand feet, growth hormone deficiency andhypogenitalism/hypogonadism, there are alsobehavioural characteristics including learningdisabilities, temper tantrums, aggression, repetitivespeech, obsessive compulsive behaviour, sleep disorderand skin picking (Cassidy and Driscoll, 2009). Thisdisparate collection of symptoms led Holm et al (1993)to define the major and minor characteristics whichallowed a clinical diagnosis of this the most commongenetic form of obesity. Consensus diagnostic criteriawere defined and weighted scores in which the majorcriteria were awarded one point and the minor criteriahalf a point calculated. A score of 8 or more is clinicallydiagnostic for PWS.The majority of people with PWS have a paternallyderived deletion of approximately 5-7Mb in 15q11-q13,others have maternal disomy of chromosome 15(UPD15mat) and a minority have a defect of theimprinting centre located in exon 1 of the SNRPN genewhich leads to a maternal imprint on the paternallyderived chromosome. Any of these abnormalities willresult in loss of the paternal contribution to the Prader-Willi syndrome critical region (PWSCR), demonstratedby loss of a paternally derived unmethylated band at theimprinting centre and a lack of expression of the SNRPNgene. Although these do not differentiate between thedifferent genetic types of PWS they are diagnostic forthe syndrome (Cassidy and Driscoll, 2009; Ramsden etal, 2010; Zeschnigk et al, 1997).Within 15q11-q13 the complex imprintedSNURF/SNRPN gene hosts several untranslated snoRNAgenes located within intronic sequences. The finding ofa microdeletion involving SNORD116 in a boy with PWSled to the identification of this snoRNA as the candidategene for the syndrome (Sahoo et al, 2008).In the course of a large study of PWS in the UK(Whittington et al, 2001; Soni et al, 2007) three peoplewere identified who fulfilled the criteria for a clinicaldiagnosis of the syndrome but not the geneticlaboratory diagnostic criteria.The Affymetrix Cytogenetics Whole-Genome 2.7M arraywhile providing high resolution whole genome coveragereliably detects changes in copy number. Deletionsand/or duplications present in all three participants ifinvolved in annotated genes could potentiallycontribute to the Prader-Willi-like phenotype.Candidate genes can subsequently be evaluated toestimate their transcription levels and compared withthose shown by people with PWS and with unaffectedindividuals

Genomic surveillance of SARS-COV-2 reveals diverse circulating variant lineages in Nairobi and Kiambu Counties, Kenya

Genomic surveillance and identification of COVID-19 outbreaks are important in understanding the genetic diversity, phylogeny, and lineages of SARS-CoV-2. Genomic surveillance provides insights into circulating infections, and the robustness and design of vaccines and other infection control approaches. We sequenced 57 SARS-CoV-2 isolates from a Kenyan clinical population, of which 55 passed quality checks using the Ultrafast Sample placement on the Existing tRee (UShER) workflow. Phylo-genome-temporal analyses across two regions in Kenya (Nairobi and Kiambu County) revealed that B.1.1.7 (Alpha; n = 32, 56.1%) and B.1 (n = 9, 15.8%) were the predominant lineages, exhibiting low Ct values (5-31) suggesting high infectivity, and variant mutations across the two regions. Lineages B.1.617.2, B.1.1, A.23.1, A.2.5.1, B.1.596, A, and B.1.405 were also detected across sampling sites within target populations. The lineages and genetic isolates were traced back to China (A), Costa Rica (A.2.5.1), Europe (B.1, B.1.1, A.23.1), the USA (B.1.405, B.1.596), South Africa (B.1.617.2), and the United Kingdom (B.1.1.7), indicating multiple introduction events. This study represents one of the genomic SARS-CoV-2 epidemiology studies in the Nairobi metropolitan area, and describes the importance of continued surveillance for pandemic control

Hypothermia amongst neonatal admissions in Kenya: a retrospective cohort study assessing prevalence, trends, associated factors, and its relationship with all-cause neonatal mortality

BackgroundReports on hypothermia from high-burden countries like Kenya amongst sick newborns often include few centers or relatively small sample sizes.ObjectivesThis study endeavored to describe: (i) the burden of hypothermia on admission across 21 newborn units in Kenya, (ii) any trend in prevalence of hypothermia over time, (iii) factors associated with hypothermia at admission, and (iv) hypothermia's association with inpatient neonatal mortality.MethodsA retrospective cohort study was conducted from January 2020 to March 2023, focusing on small and sick newborns admitted in 21 NBUs. The primary and secondary outcome measures were the prevalence of hypothermia at admission and mortality during the index admission, respectively. An ordinal logistic regression model was used to estimate the relationship between selected factors and the outcomes cold stress (36.0°C–36.4°C) and hypothermia (&lt;36.0°C). Factors associated with neonatal mortality, including hypothermia defined as body temperature below 36.0°C, were also explored using logistic regression.ResultsA total of 58,804 newborns from newborn units in 21 study hospitals were included in the analysis. Out of these, 47,999 (82%) had their admission temperature recorded and 8,391 (17.5%) had hypothermia. Hypothermia prevalence decreased over the study period while admission temperature documentation increased. Significant associations were found between low birthweight and very low (0–3) APGAR scores with hypothermia at admission. Odds of hypothermia reduced as ambient temperature and month of participation in the Clinical Information Network (a collaborative learning health platform for healthcare improvement) increased. Hypothermia at admission was associated with 35% (OR 1.35, 95% CI 1.22, 1.50) increase in odds of neonatal inpatient death.ConclusionsA substantial proportion of newborns are admitted with hypothermia, indicating a breakdown in warm chain protocols after birth and intra-hospital transport that increases odds of mortality. Urgent implementation of rigorous warm chain protocols, particularly for low-birth-weight babies, is crucial to protect these vulnerable newborns from the detrimental effects of hypothermia

Comparative molecular developmental aspects of the mammalian- and the avian lungs, and the insectan tracheal system by branching morphogenesis: recent advances and future directions

Abstract Gas exchangers fundamentally form by branching morphogenesis (BM), a mechanistically profoundly complex process which derives from coherent expression and regulation of multiple genes that direct cell-to-cell interactions, differentiation, and movements by signaling of various molecular morphogenetic cues at specific times and particular places in the developing organ. Coordinated expression of growth-instructing factors determines sizes and sites where bifurcation occurs, by how much a part elongates before it divides, and the angle at which branching occurs. BM is essentially induced by dualities of factors where through feedback- or feed forward loops agonists/antagonists are activated or repressed. The intricate transactions between the development orchestrating molecular factors determine the ultimate phenotype. From the primeval time when the transformation of unicellular organisms to multicellular ones occurred by systematic accretion of cells, BM has been perpetually conserved. Canonical signalling, transcriptional pathways, and other instructive molecular factors are commonly employed within and across species, tissues, and stages of development. While much still remain to be elucidated and some of what has been reported corroborated and reconciled with rest of existing data, notable progress has in recent times been made in understanding the mechanism of BM. By identifying and characterizing the morphogenetic drivers, and markers and their regulatory dynamics, the elemental underpinnings of BM have been more precisely explained. Broadening these insights will allow more effective diagnostic and therapeutic interventions of developmental abnormalities and pathologies in pre- and postnatal lungs. Conservation of the molecular factors which are involved in the development of the lung (and other branched organs) is a classic example of nature’s astuteness in economically utilizing finite resources. Once purposefully formed, well-tested and tried ways and means are adopted, preserved, and widely used to engineer the most optimal phenotypes. The material and time costs of developing utterly new instruments and routines with every drastic biological change (e.g. adaptation and speciation) are circumvented. This should assure the best possible structures and therefore functions, ensuring survival and evolutionary success.</p