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The Cowpea (Vigna unguiculata L. Walp), is arguably commonly cultivated legume crop within sub-Saharan African region. However, regardless of the continuous increase in cultivated area for cowpea, production is significantly low. One of the most apparent biotic hindrances to cowpea yield is Meloidogyne incognita's infection. Application of synthetic nematicides is an efficient way of managing M. incognita on cowpea. However, the consideration for human and environmental safety has prompted research into innumerable substitutes inclusive of plant-mediated nanoparticles. In this study, probable nematicidal action of Borreria verticillata (L.) G. Mey. mediated nanoparticles obtained from copper, iron and zinc was assessed on M. incognita. The likely impact of each nanoparticle (NP) on quality of harvested cowpea seeds was equally evaluated. Copper, zinc and iron nanoparticles showed maximum absorbance at 308, 318 and 304 nm, respectively. Fourier-transform infrared (FTIR) spectra demonstrated notable bands attesting to B. verticillata secondary metabolites as reducing agents in the formation of NPs (4.85–50 nm). CuNPs at 100 ppm significantly increased cowpea yield by 339.8% with reference to untreated cowpea plants, while reduction in number of nematode egg mass, juvenile population in cowpea roots per 200 cc of soil was achieved with Cu and Zn NPs relative to the standard carbofuran. Oil absorption capacity was higher in Cu and Zn NPs treated seeds, bulk density was uniformly high in Cu, Zn and Fe NPs compared with untreated control seeds. No significant difference in physical characteristics of NP treated cowpea seeds. This study corroborates previous reports regarding the efficacy of some green plants serving as reducing agents in the biosynthesis of metal NPs. B. verticillata has proved potent in this regard particularly in our current study. The NPs obtained displayed qualities of a suitable substitute for synthetic nematicides in the prospect of M. incognita management, without any inconsistency in cowpea food functionality. [ABSTRACT FROM AUTHOR]

Type 2 Diabetes mellitus (T2DM) is one of the oldest known chronic diseases, characterized by elevated fasting blood sugar (FBS). T2DM is a metabolic disorder that can distort the activities of multiple physiological systems, including the reproductive system. Although different drugs have been designed for managing this disorder, these drugs have been reported to have negative side effects. Hence, this study was designed to explore the possible synergistic effect of vitamin D and exercise on T2DM-induced testicular dysfunction. Thirty-six male Wistar rats were randomized into six (6) groups: control, diabetes untreated, diabetes treated with 1000 IU/kg of vitamin D, diabetes treated with 5 min/day of physical exercise, diabetes treated with vitamin D and exercise, diabetes treated with 180 mg/kg of metformin. T2DM induction led to a significant increase in FBS, lactate, and lactate dehydrogenase, and was reversed by vitamin D supplementation and exercise. Also, vitamin D and exercise synergistically blunted T2DM-induced oxido-inflammatory response evidenced by a significant decrease in testicular malondialdehyde, interleukin 1β, interleukin 6, and tumor necrosis factor alpha, and an increase in superoxide dismutase, catalase, glutathione peroxidase, and interleukin 10. These events were associated with a decrease in T2DM-induced increase in XO, UA, and Nf-κb and an increase in T2DM-induced decrease in Nrf2. Also, vitamin D and EX reversed the observed impairment in sperm quality and testicular histology following T2DM-induction. This study revealed the synergistic effect of vitamin D and exercise on T2DM-induced testicular dysfunction. [ABSTRACT FROM AUTHOR]

Copper, iron and zinc nanoparticles (NPs) were synthesized with aqueous extract of Tridax procumbens. The NPs were characterized with UV–Vis, Fourier-transform infrared (FTIR), transmission electron microscopy (TEM), selected area electron diffraction (SAED) and energy-dispersive X-ray spectroscopy (EDX). The maximum absorbance for Cu, Fe and Zn NPs occurred at 300, 318 and 306 nm respectively. Prominent bands on the FTIR spectra established that phyto-compounds in T. procumbens extract are creditable for the reduction and stabilizing process to produce particles ranging from 2.98–100 nm. The nanoparticles were evaluated for their nematicidal activities in field trials on cabbage plants in comparison with the standard nematicide carbofuran. Potent nematicidal activity was notably displayed by the NPs at 100 ppm on Meloidogyne incognita population in 200 cc of soil, number of eggs and gall index. Significantly higher yield was recorded in cabbage plants treated with T. procumbens CuNP contrary to other NPs and untreated cabbage plants. CuNPs can be applied in M. incognita management in place of synthetic nematicides for sustainable cabbage production. [ABSTRACT FROM AUTHOR]

The Two Weeks in the World research project has resulted in a dataset of 3087 clinically relevant bacterial genomes with pertaining metadata, collected from 59 diagnostic units in 35 countries around the world during 2020. A relational database is available with metadata and summary data from selected bioinformatic analysis, such as species prediction and identification of acquired resistance genes. [ABSTRACT FROM AUTHOR]

Acinetobacter baumannii is an opportunistic pathogen that is mostly associated with hospital-acquired infections. The rapid emergence of multi- and pan-drug-resistant Acinetobacter strains poses an increasing challenge in hospitals. Phage therapy offers one treatment option for infections caused by A. baumannii. We isolated three phages from Beninese hospital wastewater – fBenAci001, fBenAci002, and fBenAci003 – that infected clinical A. baumannii strains from Finnish patients. Phylogenetic analysis showed that these phages resemble phages of the genus Friunavirus, family Autographiviridae. The isolated phages meet the requirements set for phages used for phage therapy. However, they were found to have a narrow host range, which may limit their therapeutic use. [ABSTRACT FROM AUTHOR]

Caffeine is globally consumed as a stimulant in beverages. It is also ingested in purified forms as power and tablets. Concerns have been raised about the potential consequences of intrauterine and early life caffeine exposure on brain health. This study modeled caffeine exposure during pregnancy and early postanal life until puberty, and the potential consequences. Caffeine powder was dissolved in distilled water. Thirty-two (n = 32) pregnant mice (Mus musculus) (dams) were divided into four groups- A, B, C and D. Group A animals served as a control, receiving placebo. Caffeine doses in mg/kg body weight were administered as follows: Group B, 10 mg/kg; Group C, 50 mg/kg; Group D, 120 mg/kg. Prenatal caffeine exposure [phase I] lasted throughout pregnancy. Half the number of offspring (pups) were sacrificed at birth; the rest were recruited into phase II and the experiment continued till day 35, marking puberty. Brain samples were processed following sacrifice. γ-aminobutyric acid (GABA), acetylcholine (ACh), and serotonin (5Ht) neurotransmitters were assayed in homogenates to evaluate functional neurochemistry. Anxiety and memory as neurobehavioural attributes were observed using the elevated plus and Barnes' mazes respectively. Continuous caffeine exposure produced positive effects on short and long-term memory parameters; the pattern interestingly was irregular and appeared more effective with the lowest experimental dose. Anxiety test results showed no attributable significant aberrations. Caffeine exposure persistently altered the neurochemistry of selected neurotransmitters including ACh and 5Ht, including when exposure lasted only during pregnancy. ACh significantly increased in group BC+ to 0.3475μgg-1 relative to control's 0.2508μgg-1; pre-and continuous postnatal exposure in Group B increased 5Ht to 0.2203 μgg-1 and 0.2213 μgg-1 respectively relative to control's 0.1863 μgg-1. From the current investigation, caffeine exposure in pregnancy had persistent effects on brain functional attributes including neurotransmitters activities, memory and anxiety. Caffeine in moderate doses affected memory positively but produced negative effects at the higher dosage including increased anxiety tendencies. [ABSTRACT FROM AUTHOR]

This work investigates the chemical compositions of Polyalthia longifolia Thw. seed oil with the associated antioxidant, anti-inflammatory, anti-parasite and cytotoxicity potentials. The oil of P. longifolia seed obtained by soxhlet extraction was trans-esterified and the fatty acid profile characterized using gas chromatography mass spectrometry (GC–MS). The antioxidant activity was evaluated using DPPH and ABTS assays. The anti-bacterial and anti-fungi properties of the oil were determine on clinical isolates of the organisms using agar diffusion method. The anti-inflammatory activities, cytotoxicity and anti-parasite potential were evaluated using lipooxygenase, mammalian cell and Toxoplasma gondii assays respectively. P. longifolia seed was observed to contain oleic (30.31%), linoleic acid (19.27%) and palmitic acid (15.11%) as the major fatty acids with low proportion of tricosylic acid (6.10) and stearic acid (5.56%). The oil had significant anti-lipooxygenase activity (IC50 = 0.70 ± 0.02 µg/mL) comparable to indomethacin (IC50 = 0.53 ± 0.07 µg/mL). The DPPH (IC50 = 55.91 ± 31.18 µg/mL) and ABTS (IC50 = 16.89 ± 15.50 µg/mL) antioxidant activity of the oil was lower to the ascorbic acid (IC50 = 0.34 ± 0.04 and 0.54 ± 0.04 µg/mL). The oil also showed activities against all the tested bacteria and fungi. The highest inhibition was recorded against S. aureus (17 ± 1 mm) at concentration 200 mg/mL. Further, the oils showed strong potential to restrict growth of Toxoplasma gondii in vitro, but the parasite growth inhibition was mildly abated in the presence of α-tocopherol. The seed oil of the underutilized P. longifolia possesses essential fatty acids which could be responsible for the numerous biological potentials which include anti-lipooxygenase, antioxidant, anti-inflammatory, anti-parasite, anti-microbial and cytotoxic activities. The incorporation of the natural oil into pharmaceuticals or cosmetics may enhance antioxidant, anti-inflammatory, antimicrobial and cytotoxicity potential of such products. [ABSTRACT FROM AUTHOR]

The original article can be found online at https://doi.org/10.1007/s10658-023-02792-y.Correction: European Journal of Plant Pathologyhttps://doi.org/ https://doi.org/10.1007/s10658-023-02792-yThis erratum is published as several author corrections were overlooked during proofing.Original article has been updated.By Oluwatoyin Fabiyi; Agbaje Lateef; Evariste Bosco Gueguim-Kana; Lorika Selomi Beukes; Ntombozuko Matyumza; Tesleem Bello and Gabriel OlatunjiReported by Author; Author; Author; Author; Author; Author; Author [Extracted from the article]

Objective Ethiopia is home to an increasingly large refugee population. Reproductive health care is a critical issue for these groups because refugee women are at high risk for unmet family planning needs. Efforts to expand contraceptive use, particularly long acting reversible contraceptive (LARC) methods are currently underway in several Ethiopian refugee camps. Despite availability of LARC methods, few refugee women opt to use them. The purpose of this study was to explore how culture influences contraceptive attitudes and behaviors, particularly towards LARC methods, among Ethiopia's refugee populations. Methods Focus group discussions and individual interviews were conducted with Eritrean and Somali refugees living in Ethiopia. The qualitative data was analyzed to identify important themes highlighting the relationship between cultural values and contraceptive attitudes and behaviors. Results Childbearing was highly valued among participants in both study groups. Eritreans reported desire to limit family size and attributed this to constraints related to refugee status. Somalis used cultural and religious faith to deal with economic scarcity and were less likely to feel the need to adapt contraceptive behaviors to reduce family size. Participants held overall positive views of the contraceptive implant. Attitudes toward the intrauterine device (IUD) were overwhelmingly negative due to its long-acting nature. Conclusions Culture, religion and refugee status form a complex interplay with family planning attitudes and behaviors among Eritrean and Somali refugees. For these populations, the three-year implant appears to be a more acceptable contraceptive method than the longer-acting IUD because it is in line with their reproductive plans. [ABSTRACT FROM AUTHOR]

Urban space administration is a branch of public administration designated for ordering, re-ordering, regulating and controlling urban systems and urban land uses for the purpose of human comfort, convenience, urban aesthetic or city's branding and economic and environmental sustainability. Urban space administration is not new in Nigeria; it dated back to precolonial periods when city management was vested in kings and a team of advisers including the local priests. The advent of colonial government introduced paper-assisted urban administration which continued after independence. The 1976 local government reforms and the subsequent fragmentations of states to many local government resulted in multiplicity of admirations and agencies governing urban areas in Nigeria. The results are manifested in blighted condition and pockets of slums in all Nigeria cities. The paper examined trends in urban administration in Nigeria and advanced two approaches to solving multifarious urban problems in Nigeria. The approaches include devolution of urban administration powers to local authorities and deployment of geospatial technology tools for urban system administrators ( Knaap et al 1998). The paper further suggested recommendations for bridging the digital shortfall in the applications of modern technologies to city administration in Nigeria. [ABSTRACT FROM AUTHOR]

This project developed and studied The Source, an alternate reality game (ARG) designed to foster interest and knowledge related to science, technology, engineering, and math (STEM) among youth from populations underrepresented in STEM fields. ARGs are multiplayer games that engage participants across several media such as shared websites, social media, personal communications, and real-world settings to complete activities and collaborate with team members. The Source was a five-week summer program with 144 participants from Chicago aged 13 to 18 years. The Source incorporated six socio-contextual factors derived from three frameworks: Chang's (ERIC Digest, 2002) recommendations for engaging underrepresented populations in STEM careers, Lave and Wenger's (Cambridge University Press, 1991) situated learning model, and Barron's (Human Development, 49(4); 193-224, 2006) learning ecology perspective. These factors aligned with the program's aims of promoting (1) social community and peer support, (2) collaboration and teamwork, (3) real-world relevance and investigative learning, (4) mentoring and exposure to STEM professionals, (5) hands-on activities to foster transferable skill building, and (6) interface with technology. This paper presents results from 10 focus groups and 10 individual interviews conducted with a subset of the 144 youth participants who completed the game. It describes how these six factors were realized through The Source and uses them as a lens for considering how The Source functioned pedagogically. Qualitative findings describe youth's perception of The Source's potential influence on STEM interest, engagement, and identity formation. Despite limitations, study results indicate that underrepresented youth can engage in an immersive, narrative, and game-based experience as a potential mechanism for piquing and developing STEM interest and skills, particularly among underrepresented youth. [ABSTRACT FROM AUTHOR]

Objective To explore nativity differences and the role of attitudes, social norms, and behavioral control perceptions surrounding breastfeeding initiation and duration among middle-class African-American (AA) and African-born (AB) mothers in the US. Methods Semi-structured individual interviews were conducted with 20 middle-class AA and AB mothers in central Ohio from December 2012 to February 2013. Interview questions were developed based on the Theory of Planned Behavior (TPB). Interviews were analyzed for salient themes by TPB constructs. Differences in themes were examined by nativity status. Results All study participants had initiated breastfeeding or bottle-feeding with expressed breast milk, noting the benefits it conferred as well as the persuasive encouragement they received from others. Persistent encouragement was often cited as a factor for sustaining breastfeeding. More AA mothers had discontinued breastfeeding by the time of the interview, which was often attributed to health, lactation, and work challenges. Inconsistent support from health providers, dissuasive remarks from others, ambivalent breastfeeding attitudes, and diminished family support led some mothers to begin formula supplementation. Analysis of maternal narratives revealed nativity differences across sources of encouragement. Specifically, important sources of encouragement were health providers for AA mothers and family, friends, partners and culture for AB mothers. Only AB mothers expressed concerns about difficulty they encountered with breastfeeding due to the lack of proximal family support. Conclusions Findings reveal that both groups of mothers may be susceptible to unsupportive breastfeeding norms in the US and also highlight the need for intervention in health care settings and workplaces to improve AA women's breastfeeding rates. [ABSTRACT FROM AUTHOR]

Parkinson's disease has long been described to be a product of dopamine and (or) melanin loss in the substanstia nigra (SN). Although most studies have focused on dopaminergic neurons, it is important to consider the role of pigment cells in the etiology of the disease and to create an in vitro live cell model for studies involving pigmented adrenergic cells of the SN in Parkinsonism. The Melanocytes share specific features with the pigmented adrenergic neurons as both cells are pigmented, contain adrenergic receptors and have cellular processes. Although the melanocyte cellular processes are relatively short and observable only when stimulated appropriately by epinephrine and other factors or molecules. This study employs the manipulation of N-Methyl-D-Aspartate Receptor (NMDA-R), a major receptor in neuronal development, in the process formation pattern of the melanocyte in order to create a suitable model to depict cellular process elongation and shortening in pigmented adrenergic cells. NMDA-R is an important glutamate receptor implicated in neurogenesis, neuronal migration, maturation and cell death, thus we investigated the role of NMDA-R potentiation by glutamate/KCN and its inhibition by ketamine in the behavior of fish scale melanocytes in vitro. This is aimed at establishing the regulatory role of NMDA-R in this cell type (melanocytes isolated form Tilapia) in a similar manner to what is observable in the mammalian neurons. In vitro live cell culture was prepared in modified Ringer's solution following which the cells were treated as follows; Control, Glutamate, Ketamine, Glutamate + Ketamine, KCN + Ketamine and KCN. The culture was maintained for 10 min and the changes were captured in 3D-Time frame at 0, 5 and 10 min for the control and 5, 7 and 10 min for each of the treatment category. Glutamate treatment caused formation of short cellular processes localized directly on the cell body while ketamine treatment (inhibition of NMDA-R) facilitated elongation of secondary cellular processes (highly branched) from primary major processes (Less branched); co-incubation of glutamate and ketamine induced short and highly branched process formation. Cyanide toxicity induced degeneration and reduction of cell size while co-treatment of cyanide and ketamine gave changes similar to that observed in glutamate-ketamine co-incubation. NMDA-R is present in the melanocytes. Activation of the receptor reduced elongation process, while inhibition of the receptor facilitated cell process elongation and branching. This confirms that like pigmented adrenergic cells of the nervous system, this cell contains NMDA-R and this receptor also regulates cell process elongation. The study also showed that inhibition of NMDA-R in melanocytes gave opposite outcomes to the role of the receptor in developing neurons; a function that is protective in adult neurons. [ABSTRACT FROM AUTHOR]

Glia activation and neuroinflamation are major factors implicated in the aetiology of most neurodegenerative diseases (NDDs). Several agents and toxins have been known to be capable of inducing glia activation an inflammatory response; most of which are active substances that can cause oxidative stress by inducing production of reactive oxygen species (ROS). Neurogenesis on the other hand involves metabolic and structural interaction between neurogenic and glia cells of the periventricular zone (PVZ); a region around the third ventricle. This study investigates glia activation ( GFAP), cell proliferation ( Ki-67) and neuronal metabolism ( NSE) during neurogenesis and oxidative stress by comparing protein expression in the PVZ against that of the parietal cortex. Adult Wistar Rats were treated with normal saline and 20 mg/Kg KCN for 7 days. The tissue sections were processed for immunohistochemistry to demonstrate glia cells (anti Rat-GFAP), cell proliferation (anti Rat-Ki-67) and neuronal metabolism (anti Rat-NSE) using the antigen retrieval method. The sections from Rats treated with cyanide showed evidence of neurodegeneration both in the PVZ and cortex. The distribution of glia cells (GFAP), Neuron specific Enolase (NSE) and Ki-67 increased with cyanide treatment, although the increases were more pronounced in the neurogenic cell area (PVZ) when compared to the cortex. This suggests the close link between neuronal metabolism and glia activation both in neurogenesis and oxidative stress. [ABSTRACT FROM AUTHOR]

This study investigated weathering effects on polyvinyl chloride (PVC) based wood plastic composites (WPC), with a focus on the color and structure that is attributed to the material composition. It is directed towards quantifying the main chemical modifications, such as carbonyl and vinyl groups which are formed during weathering. These composites were subjected to three weathering regimes: exterior, accelerated xenon-arc, and accelerated UVA. The change in color was monitored using colorimetry. Fourier transform infrared spectroscopy was used to identify and quantify the chemical modifications (carbonyl formation and vinyl propagation) due to weathering. Additionally, scanning electron microscopy was employed to observe the physical morphological changes that occurred. The results showed that exterior and accelerated xenon-arc and UVA weathering regimes increased the degree of lightness, total color change, carbonyl concentration, and wood loss on the surfaces of the weathered composites. The increased carbonyl concentration during weathering implied that degradation had occurred by oxidation process. Also, oxidation and lignin (from the wood) degradation influenced the color (lightness) of PVC based WPC upon weathering. [ABSTRACT FROM AUTHOR]

The effects of weathering on the constituents of wood and polymer matrix behavior in wood plastic composites (WPCs) were investigated. WPCs were produced from pine, extractives-free pine, and pine holocellulose fibers (60%) together with HDPE (40%). These composites were subjected to xenon-arc accelerated and outside weathering for a total of 1200 h and 120 days, respectively. The color and chemical changes that occurred on the surface of the WPCs were analyzed using a set of analytical techniques. For pine and extractive-free pine filled composites, the results showed that the total color change, lightness, and oxidation increased, while the lignin content decreased. In addition, the weight average molecular weight ( Mw) and number average molecular weight ( Mn) of extracted HDPE decreased with an increase in exposure time of the composites. However, HDPE crystallinity increased with longer exposure time. Lightness of holocellulose-based WPC changed the least while the change in its HDPE crystallinity was not significant compared to the other composite types. Therefore, holocellulose-based WPC may be preferred for applications where color stability is of high priority. [ABSTRACT FROM AUTHOR]

The article presents the case studies of Johannesburg, South Africa and Ibadan, Nigeria on the recent trends in urban space partitioning due to the increased crime rate. The positive effects of road closures such as community development, local governance and security are discussed. The negative effects such as mobility and traffic jams are discussed. The usage of CCTV and alarm systems technologies with participation of residents in associations is suggested for neighbourhood protection.

The purpose of this study was to test the reliability of the Well-being and Diabetes Treatment Satisfaction Questionnaires among clinic patients with type 2 diabetes as well as determine the clinical correlates of these measures. A cross-sectional survey was conducted using the Well-being Questionnaire and the Diabetes Treatment Satisfaction Questionnaire. Other demographic and clinical indices of age, sex, body mass index, disease duration and blood glucose levels were also recorded. 83 responses were analysed. Subjects were aged between 25 and 75 years, mean 55.5 ± 11.1 years. 50.6% were males while 49.4% were females. Mean diabetes duration was 4.9 ± 6.5 years. 67 (80.7%) were receiving oral agents and dietary modification while 16 (19.3%) were on insulin therapy. The internal consistency for responses to the well-being subscales and treatment satisfaction scale produced satisfactory α coefficients ranging from 0.73 to 0.88 and 0.74 respectively. Inter-item correlations were ranged between 0.19 and 0.45 for depression subscale; 0.22–0.78 for anxiety subscale; 0.33–0.58 for energy subscale; 0.33–0.79 for positive well-being subscale; and -0.22 to 0.79 for the treatment satisfaction scale. Item-total correlations ranged between 0.39 and 0.87 across the two scales: well-being (0.59–0.87) and treatment satisfaction (0.39–0.78). Mean scale scores were similar in both insulin and oral hypoglycaemic drug treated patients. Positive well-being was higher in males 13.4 ± 4.1 vs. 11.5 ± 4.3 in females p = 0.04. None of the well-being subscale scores, or treatment satisfaction correlated with age, disease duration, body mass index or glycaemic control. The well-being and treatment satisfaction scales are reliable instruments for the measurement of diabetes specific quality of life and treatment satisfaction in Nigerians although they were originally designed and developed among a UK population. It is hoped that our data would provide the basis for future comparisons and improving diabetes care. [ABSTRACT FROM AUTHOR]

Discusses a survey of the attitudes and practices regarding school health education of 600 secondary school teachers and 120 secondary school administrators in Oyo State, Nigeria. Lack of resources and curriculum time devoted to health education; Belief of the survey participants in the importance of health education; Variety of reasons for teaching health in the schools; Methods; Results; More.

Seven isolates of West Nile virus and an additional isolate tentatively identified at the outset as West Nile virus, were compared by Casals' modified haemagglutination inhibition technique. Two of the isolates were nearly identical; a second set of five isolates cross-reacted among themselves within a wide range and differed from the first two; the last isolate was significantly different from the others. [ABSTRACT FROM AUTHOR]

Orungo virus was studied in cell culture and mice by light and electron microscopy. The virus developed in the cytoplasm of infected cells in mouse brain and cell culture in association with a specific viral granular matrix and accompanying filaments. Virus particle size was 63 nm with a core diameter of 34 nm. Most particles were released from infected cells by lysis, but some budded through membranes and assumed a 'pseudoenvelope'. In its morphology and mode of morphogenesis, Orungo virus was indistinguishable from other described orbiviruses. [ABSTRACT FROM AUTHOR]

Wild-caught shrews ( Crocidura sp.), the only known wildlife host of the rabiesrelated agent Mokola virus, were given various dose levels of Mokola virus by different routes (subcutaneous, intramuscular, and oral), and then were examined for recovery of virus, presence of histopathologic lesions, and ability to transmit virus by bite to laboratory mice. Thirteen shrews, given virus by each of the routes, showed evidence of having become infected. Eleven of these became ill and yielded virus from multiple tissues, in which lesions were observed. Of the two infected shrews that remained asymptomatic, both showed histopathologic lesions and one also yielded virus, while the other was virus-negative (only brain was tested) but transmitted virus to a mouse. Four of the shrews that were virus-positive also transmitted the virus to mice. Thirty other inoculated shrews, as well as control shrews, did not yield virus and failed either to show lesions compatible with Mokola virus infection or to transmit virus. [ABSTRACT FROM AUTHOR]

Using the method of constant column length and unpurified and unconcentrated virus, the sedimentation constants of the infectious and hemagglutinating (HA) units of ECHO virus 19 were determined. The two were very close with an average value of 157 ±7.6 S units. The distributions of the infectivity, HA and complement-fixing antigen (CF) of the virus in CsCl equilibrium density gradients were studied. An infectivity peak was found at a density of 1.34 g/ml.; two bands of HA activity were noted at densities of 1.34 g/ml. and 1.29 g/ml. Eighty to 90% of the HA activity was located at the 1.34 g/ml. density and 12-20% at the lower density (1.29 g/ml.). Electron micrographs show that ECHO virus 19 has a diameter size of 28 ±5 mμ. Particles negatively stained with PTA show the presence of complete virus at the 1.34 g/ml. density with evidence of polyhedral structure while those isolated from the 1.29 g/ml. density band lack such a structure and are considered to be incomplete particles. [ABSTRACT FROM AUTHOR]

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