Process optimization of the mechanical properties of AISI 1020 steel quenched using maize-stover ash potash solution

The process parameter optimization of maize-stover ash potash (MSAP) as a quenching medium for heat treatment of AISI-1020 steel was conducted in this study to improve the mechanical properties of steel after carburization and quenching. The optimization process utilized Taguchi L9(32) orthogonal array method to determine the individual Signal to Noise (S/N) ratio and Analysis of Variance (ANOVA). A multi-response weighted analysis technique was applied to derive combined quality responses of the heat treated test pieces. The result shows that the optimal factor level of MSAP solution strength was achieved at AM1BM1, which offered 57.6 HRC hardness, 39 J toughness and 1971 N/mm2 tensile strength as improved mechanical properties for the heat treated steel. Keywords: Optimization, MSAP, quenching, Taguchi, ANOV

Extraction, Maceration and Assessment of Potential toxicity of Crude Ethanol Leaf-Extract and Fractions of Naucleadiderrichii

Naucleadiderrichii is widely used in folk medicine in the treatment of infectious diseases inMada District, Gusau, Zamfara State, Nigeria and other parts of Africa. This study deals with the extraction, maceration and evaluation of the level of toxicity in crude ethanol leaf-extract and other fractions of the crude using Artemiasalina(brine shrimp) model. The crude leaf-extract (Nd-CETE), was extracted using absolute ethanol, while the fractions (Nd-PETF, Nd-CHLF and Nd-EAF) of the crude were obtained through maceration using solvents of varying polarity gradient (petroleum ether, chloroform and ethyl acetate). The lethality of the Brine shrimp nauplii was in a concentration dependent fashion, with increasing lethality due to increase in concentration of the crude extract/fractions. The Lethality ofcrude extract and those of fractions were based on Meyerʼs index of toxicity. Fractions of petroleum ether and Chloroform were found to be non-toxicity withLC50 3,239.09 and 1,574.60 µg/mLrespectively, while the crude ethanolleaf-extract (Nd-CETE) and ethyl acetate fraction (Nd-EAF) demonstrated high levels of toxicity in Artemiasalina with LC50342.90 and 578.08 µg/mL respectively, which signify toxicity in a brine shrimp model. The study concludes that, the crude leaf-extract and ethyl acetate fraction of Naucleadiderrichiipossesses cytotoxic behavior, suggesting the presence of potential bioactive chemical components. Further in vivo and cell lines cytotoxicity test is recommended to substantiate these findings

Toxicity Study and Anticonvulsant Effect of Ethanol Leaf Extract of Piliostigma thonningii Milne-Redhead (Fabaceae)

Background: Piliostigma thonningii (Schumach) Milne-Redhead [Fabaceae] is a plant widely used locally for the treatment and management of several ailments which include epilepsy in Northeastern Nigeria.Objectives: This study aimed at evaluation of the toxicity and anticonvulsant effect of ethanol leaf extract of Piliostigma thonningii in rats and mice with a view to determining the efficacy of the plant as an anticonvulsant drug.Methods: Fresh leaves of Piliostigma thonningii were air-dried, pulverized and extracted using soxhlet extraction apparatus. Acute toxicity study was carried out by Lorke’s method and the anticonvulsant activity of the ethanol leaf extract was carried using pentylenetetrazole and strychnine-induced convulsion model on Wistar strain albino rats and mice respectively.Result: The soxhlet extraction yielded 21.04% w/w of extract after being concentrated. The oral and intraperitoneal LD50 were ≥ 5000 mg/kg implying that the extract is relatively safe according to literatures. Anticonvulsant effect of the ethanol leaf extract using pentylenetetrazole (PTZ), revealed the ability of the extract to confer protection on rats treated with doses of 200, 400 and 600 mg/Kg bd. wt. by exerting 60%, 80% and 80% protection on rat against PTZ induced convulsion respectively in a dose dependent manner as well as protected 20%, 60% and 80% of mice against death induced by strychnine when treated with 100, 200 and 400 mg/kg of ethanol extract.Conclusion: The ethanol leaf extract of Piliostigma thonningii was able to provide anticonvulsant effect and is relatively safe for consumption as medicine

Clinical Presentation of a Complex Neurodevelopmental Disorder Caused by Mutations in ADNP

BACKGROUND: In genome-wide screening studies for de novo mutations underlying autism and intellectual disability, mutations in the ADNP gene are consistently reported among the most frequent. ADNP mutations have been identified in children with autism spectrum disorder comorbid with intellectual disability, distinctive facial features, and deficits in multiple organ systems. However, a comprehensive clinical description of the Helsmoortel-Van der Aa syndrome is lacking.METHODS: We identified a worldwide cohort of 78 individuals with likely disruptive mutations in ADNP from January 2014 to October 2016 through systematic literature search, by contacting collaborators, and through direct interaction with parents. Clinicians filled in a structured questionnaire on genetic and clinical findings to enable correlations between genotype and phenotype. Clinical photographs and specialist reports were gathered. Parents were interviewed to complement the written questionnaires.RESULTS: We report on the detailed clinical characterization of a large cohort of individuals with an ADNP mutation and demonstrate a distinctive combination of clinical features, including mild to severe intellectual disability, autism, severe speech and motor delay, and common facial characteristics. Brain abnormalities, behavioral problems, sleep disturbance, epilepsy, hypotonia, visual problems, congenital heart defects, gastrointestinal problems, short stature, and hormonal deficiencies are common comorbidities. Strikingly, individuals with the recurrent p.Tyr719* mutation were more severely affected.CONCLUSIONS: This overview defines the full clinical spectrum of individuals with ADNP mutations, a specific autism subtype. We show that individuals with mutations in ADNP have many overlapping clinical features that are distinctive from those of other autism and/or intellectual disability syndromes. In addition, our data show preliminary evidence of a correlation between genotype and phenotype.Genetics of disease, diagnosis and treatmen

The ASOS Surgical Risk Calculator: development and validation of a tool for identifying African surgical patients at risk of severe postoperative complications

Background: The African Surgical Outcomes Study (ASOS) showed that surgical patients in Africa have a mortality twice the global average. Existing risk assessment tools are not valid for use in this population because the pattern of risk for poor outcomes differs from high-income countries. The objective of this study was to derive and validate a simple, preoperative risk stratification tool to identify African surgical patients at risk for in-hospital postoperative mortality and severe complications. Methods: ASOS was a 7-day prospective cohort study of adult patients undergoing surgery in Africa. The ASOS Surgical Risk Calculator was constructed with a multivariable logistic regression model for the outcome of in-hospital mortality and severe postoperative complications. The following preoperative risk factors were entered into the model; age, sex, smoking status, ASA physical status, preoperative chronic comorbid conditions, indication for surgery, urgency, severity, and type of surgery. Results: The model was derived from 8799 patients from 168 African hospitals. The composite outcome of severe postoperative complications and death occurred in 423/8799 (4.8%) patients. The ASOS Surgical Risk Calculator includes the following risk factors: age, ASA physical status, indication for surgery, urgency, severity, and type of surgery. The model showed good discrimination with an area under the receiver operating characteristic curve of 0.805 and good calibration with c-statistic corrected for optimism of 0.784. Conclusions: This simple preoperative risk calculator could be used to identify high-risk surgical patients in African hospitals and facilitate increased postoperative surveillance. © 2018 British Journal of Anaesthesia. Published by Elsevier Ltd. All rights reserved.Medical Research Council of South Africa gran

Safety of hospital discharge before return of bowel function after elective colorectal surgery

Background: Ileus is common after colorectal surgery and is associated with an increased risk of postoperative complications. Identifying features of normal bowel recovery and the appropriateness for hospital discharge is challenging. This study explored the safety of hospital discharge before the return of bowel function. Methods: A prospective, multicentre cohort study was undertaken across an international collaborative network. Adult patients undergoing elective colorectal resection between January and April 2018 were included. The main outcome of interest was readmission to hospital within 30 days of surgery. The impact of discharge timing according to the return of bowel function was explored using multivariable regression analysis. Other outcomes were postoperative complications within 30 days of surgery, measured using the Clavien\u2013Dindo classification system. Results: A total of 3288 patients were included in the analysis, of whom 301 (9\ub72 per cent) were discharged before the return of bowel function. The median duration of hospital stay for patients discharged before and after return of bowel function was 5 (i.q.r. 4\u20137) and 7 (6\u20138) days respectively (P < 0\ub7001). There were no significant differences in rates of readmission between these groups (6\ub76 versus 8\ub70 per cent; P = 0\ub7499), and this remained the case after multivariable adjustment for baseline differences (odds ratio 0\ub790, 95 per cent c.i. 0\ub755 to 1\ub746; P = 0\ub7659). Rates of postoperative complications were also similar in those discharged before versus after return of bowel function (minor: 34\ub77 versus 39\ub75 per cent; major 3\ub73 versus 3\ub74 per cent; P = 0\ub7110). Conclusion: Discharge before return of bowel function after elective colorectal surgery appears to be safe in appropriately selected patients