Statistical modeling of Si-based refractory compounds of bamboo leaf and alumina reinforced Al-Si-Mg alloy hybrid composites.

Wear properties of Al-Mg-Si alloy matrix hybrid composites made with Si-based refractory compounds (SBRC) derived from bamboo leaf ash (BLA) as complimentary reinforcement with alumina have been studied. The experimental result indicate that optimum wear loss was obtained at higher sliding speed. The wear rate of the composites increased with an increase in BLA wt. %, with the composites having 4%SBRC from BLA + 6% alumina (B4) showing the least wear loss for the different sliding speeds and wear loads considered. With increasing BLA weight percent, the composites' wear mechanism was mostly abrasive wear. Numerical optimization results using central composite design (CCD) reveal that at a wear load of 587.014N, sliding speed of 310.053 rpm and B4 hybrid filler composition level respectively, minimum responses in wear rate (0.572mm2/min), specific wear rate (0.212cm2/g.cm3) and wear loss (0.120 g) would be obtained for the developed AA6063 based hybrid composite. Perturbation plots indicate that the sliding speed have more impact on wear loss, while wear load have significant impact on the wear rate and specific wear rate.

Achieving effective interlayer bonding of PLA parts during the material extrusion process with enhanced mechanical properties.

The additive manufacturing technique of material extrusion has challenge of excessive process defects and not achieving the desired mechanical properties. The industry is trying to develop certification to better control variations in mechanical attributes. The current study is a progress towards understanding the evolution of processing defects and the correlation of mechanical behavior with the process parameters. Modeling of the 3D printing process parameters such as layer thickness, printing speed, and printing temperature is carried out through L27 orthogonal array using Taguchi approach. In addition, CRITIC embedded WASPAS is adopted to optimize the parts' mechanical attributes and overcome the defects. Flexural and tensile poly-lactic acid specimens are printed according to ASTM standards D790 and D638, respectively, and thoroughly analyzed based on the surface morphological analysis to characterize defects. The parametric significance analysis is carried out to explore process science where the layer thickness, print speed, and temperature significantly control the quality and strength of the parts. Mathematical optimization results based on composite desirability show that layer thickness of 0.1 mm, printing speed of 60 mm/s, and printing temperature of 200 °C produce significantly desirable results. The validation experiments yielded the maximum flexural strength of 78.52 MPa, the maximum ultimate tensile strength of 45.52 MPa, and maximum impact strength of 6.21 kJ/m2. It is established that multiple fused layers restricted the propagation of cracks with minimum thickness due to enhanced diffusion between the layers.

On the analyses of carbon atom diffused into grey cast iron during carburisation process.

The study employed Fick's second law of diffusion to discover some unknown aspect of carbon diffusion in grey cast iron during carburisation process. Emphasis on the experiments and theoretical modelling were established for better accomplishments. Pulverised palm kernel and eggshell additives of 70 (wt.%) and 30 (wt.%) according to the Voige law of mixture was considered as a continuous medium without considering the atomic nature of the mixture. Furthermore, a kinetic approach was described where a physical model of the substrate immersed in the carbon mixture was established while diffusion equations were modelled to establish the mechanism of carbon diffusion during carburisation. Initial composition and concentration of diffused atom remained constant which are 2.68 and 6.67% carbon. While the carburizing time used varied from 60 min, 90 min, 120 min, 150 min, 180 min and 210 min respectively at constant carburising temperature of 900° The results revealed varying composition gradient of carbon atom ranging from 5.4%, 5.42%, 5.44%, 5.46%, 5.51%, and 5.65 compared to the initial carbon content of 2.68%. The concentration of carbon atom on the substrate surface at varying time implies that the process was non-steady state diffusion which verified Fick's second law of diffusion. Hence, the composition achieved is a function of boundary conditions such as time position and temperature. This novel study will enhance the understanding of heat treat treatment of metals such that their applications in the industry will be numerous.

Phase 2 Assessment of a New Functional Pain Scale by Comparing It to Traditional Pain Scales.

Background Assessment of pain has always been subjective and is commonly assessed using a numeric pain scale (NPS) or Wong-Baker faces scale. The pain intensity score is not standardized and relies on individuals' past experiences. The disadvantage of using such pain assessment scales and treating the numbers can lead to overdosing on analgesics leading to unwanted side effects. The Robert Packer Hospital/Functional Pain Scale (RPH/FPS) was developed as a tool for the objective assessment of pain and its impact on a patient's function.  Aim The study aimed to validate the RPH/FPS scale against NPS and Wong-Baker faces scale in medical, surgical, and trauma patients. The patients' were also asked to rank the scales as one (1) being the most preferred to three (3) being the least preferred. Design This prospective, observational cohort study compares the two most common pain scales, the NPS and the Wong-Baker Faces, to the RPH/FPS. Methods Spearman correlation was used to test for correlation between the three scales, and Wilcoxon rank-sum test was used to compare means between the RPH/FPS and NPS. The study participants were also asked to rate their preferences for the scales by rating the most preferred of the three scales as one (1) and the least preferred number three (3).  Results The RPH/FPS had a strong correlation with both the NPS and Wong-Baker Faces scales (RPH/FPS vs. NPS R=0.69, p<0.001: RPH-FPS vs. Wong-Baker Faces R=0.69, P<0.001). As for preferences, the RPH/FPS was ranked first on 36.9% of the surveys followed by NPS on 35.9%, and the Wong-Baker Faces on 22.3%. There were 4.9% of the surveys missing the preference rankings. Conclusion The results validate the RPH/FPS scale against the NPS and Wong-Baker Faces scales. This gives the clinicians a tool for objective assessment of pain and its effect on the recovery process, thereby minimizing the observed disconnect that sometimes happens between the reported pain intensity level and the providers' observation of the patient.

Retraction: Phase 2 Assessment of a New Functional Pain Scale by Comparing It to Traditional Pain Scales.

[This retracts the article DOI: 10.7759/cureus.24522.].

Analysis of serum placental growth factor levels in preeclamptic and normotensive pregnant women in Lagos, Nigeria: a worthwhile screening tool?

The clinical usefulness of serum placental growth factor (PlGF) as a predictive biomarker of preeclampsia is currently being examined. However, there are still conflicting results in the literature. We assessed the association between maternal low PlGF levels and the occurrence and severity of preeclampsia. This was an analytical cross-sectional study conducted among 60 women with preeclampsia, and an equal number of matched normotensive pregnant women. PlGF concentrations were analysed using the ELISA method. Bivariate and multivariate analysis was used to test for the association between low maternal PlGF levels and the occurrence of preeclampsia and its severity. Statistical significance was reported at p < .05. The study showed that having a low maternal PlGF level (Adjusted OR 14.23; 95%CI 8.06, 29.71) together with being primigravid (Adjusted OR 3.97; 95%CI 1.03, 6.18) and having an unbooked pregnancy (Adjusted OR 8.07; 95%CI 2.06, 19.40) were independently associated with preeclampsia. We established an association between low maternal PlGF levels and preeclampsia, but no similar association with severe preeclampsia. The use of PlGF as a potential predictive marker and a reliable screening tool may have a profound implication on the prevention of preeclampsia and the subsequent reduction in its associated morbidity and mortality.Impact statementWhat is already known on this subject? The utility of serum placental growth factor (PlGF) as a predictive biomarker of preeclampsia is currently being examined, however, there are conflicting results of its clinical usefulness in the literature.What do the results of this study add? This study that assessed the association between maternal low PlGF levels and the occurrence and severity of preeclampsia showed that having a low maternal PlGF level together with being primigravid and having an unbooked pregnancy were independently associated with the occurrence of preeclampsia. However, we were unable to establish any significant relationship between maternal PlGF and the severity of preeclampsia.What are the implications of these findings for clinical practice and/or further research? We opined that the use of PlGF as a potential predictive marker and a reliable screening tool may have a profound clinical implication on the prevention and reduction in the associated morbidity and mortality of preeclampsia. However, there is an urgent need for more robust longitudinal studies to define the regulation of placental vascular development and the clinical usefulness of maternal serum PlGF and other placental biomarkers as potential screening tools for preeclampsia among black African women.

Optimization of selected casting parameters on the mechanical behaviour of Al 6061/glass powder composites.

Aluminum alloy and its composites have versatile applications and can be produced via a cost-effective stir casting technique. However, stir casting is faced with some challenges including segregation, occurrence of intermetallic phases, agglomeration, and inducement of residual stress. In view of minimizing these defects, casting should be done applying optimal parameters that will yield the desired outcome. The present study focused on the optimization of stirring parameters of temperature, speed, and time in the production of Al 6061/glass powder composite. Evaluated responses are tensile strength, compressive strength, impact strength, and hardness. The results showed that the process parameters had statistical significance on all properties at 95 % confidence level. Combined interactions of these parameters also presented significant effects on the property responses. Optimum setting for process factors as regards tensile strength were evaluated to be 600 °C, 400 rpm, and 30 min for temperature, speed, and time, respectively. For compressive strength, it is 600 °C, 500 rpm, and 30 min; for hardness, the optimum settings are 700 °C, 400 rpm, and 30 min, while in the case of impact strength, the optimum settings are 500 °C, 400 rpm, and 30 min respectively. Optimization of the combined characteristics was obtained at the optimum conditions of 500 °C, 400 rpm, and 30 min for stirring temperature, speed, and time. Moreso, the significance of the parameters on the composite in descending order is temperature, time, and speed.

Mechanical and optimization studies of polypropylene hybrid biocomposites.

Towards developing a polymeric matrix characterized by high strength to cost ratio, polypropylene (PP) was hybridized with low-cost particulate snail shell (PSS) and kenaf fiber (KF) via compression moulding at 180 °C and 0.2 MPa. The developed composites were grouped into three and labeled as mix 2, 4, and 10. Each group entailed the blend of 5, 10, 20, and 30 wt% KF with 2, 4, 10 wt% PSS respectively. From the results, it is observed that the hardness value was enhanced by the blend of 5 to 30 wt% KF and 2, 4, and 10 wt% PSS. However, 2 wt% PSS mix with 5 to 30 wt% KF resulted in progressive improvement in impact, compressive, flexural, and tensile strengths values. The 4 wt% PSS yielded consecutive increase in impact, compressive and flexural strength when combined with 5 and 10 wt% KF. However, it was observed that subsequent addition of 20 and 30 wt% KF led to a marginal reduction in the strength values. The tensile strength attained optimum value when 4 wt% PSS was commixed with 30 wt% KF. Conversely, the combinations of 10 wt% PSS with 5, 10, 20, and 30 wt% KF had no significant improvement to the mechanical properties of PSS/KF-bio-PP composite (except for hardness) siring strength decrease. Taguchi optimization revealed that the collage of 4 wt% PSS and 10 wt% KF presented optimum mix for hybrid bio-PP composite.

Investigation of the effects of pretreatment on the elemental composition of ash derived from selected Nigerian lignocellulosic biomass.

Lignocellulosic biomass is an important source of renewable energy and a potential replacement for fossil fuels. In this work, the X-ray fluorescence (XRF) method was used to analyze the elemental composition of raw and pretreated lignocellulosic biomass of cassava peels, corn cobs, rice husks, sugarcane bagasse, yam peels, and mixtures of cassava peels and yam peels, corn cobs and rice husks and all five biomass samples combined. The influence of particle size on elemental properties was investigated by screening the selected biomass into two size fractions, of an average of 300 and 435 µm, respectively. The total concentration of Mg, Al, Si, P, S, Cl, Ca, Ti, Cr, Mn, Fe, Co, Cu, Zn, Sn, Ni, Br, Mo, Ba, Hg, and Pb were determined for each of the biomass samples before and after the different pretreatments adopted in this study. From the results of the analysis, there was a significant reduction in the concentration of calcium in all the analyzed biomass after the alkaline pretreatment with rice husks biomass having the lowest concentration of 66 ppm after the alkaline pretreatment. The sulfur content of the acid pretreated biomass increased considerably which is likely due to the sulfuric acid used for the acid pretreatment. The fact that a mixture of biomass feedstock affects the properties of the biomass after pretreatment was validated in the mixed biomass of cassava peels and yam peels biomass as an example. The concentration of Mg in the mixed biomass was 1441 ppm but was 200 ppm and 353 ppm in individual cassava peels and yam peels respectively. The results of this study demonstrated that pretreated mixtures of biomass have varied elemental compositions, which could be an important factor affecting downstream processes, especially if a hybrid feedstock is used in a large-scale application.

Optimization studies of stir casting parameters and mechanical properties of TiO2 reinforced Al 7075 composite using response surface methodology.

Stir casting is a common metallurgical route in the casting of aluminum composites. Series of work done in this aspect considered the development of the composites with fixed stir casting parameters without applying an optimization approach. These parameters affect the microstructure and performance of the composites. The study is focused on the optimization of the stir casting parameters in the production of Al 7075 reinforced with TiO2 microparticles for performance improvement. Three stir casting parameters of stirring temperature, speed, and time were varied and optimized using the central composite design technique of the response surface method. Properties evaluated were ultimate tensile strength, hardness, impact strength, elastic modulus, and compressive strength. ANOVA results showed that the three stir casting parameters had a significant impact on the property responses. Five quadratic models were established for the properties linking them to the factors. The models were confirmed to be statistically significant at a confidence level of 95% and variations were observed to be < 5%. The interaction profile of the parameters as per response surface was analyzed. Contour plots associated with each interaction gave different ranges of stirring parameters in which each property can be maximized. Simultaneous optimization of the properties using Minitab 19 software showcased 779.3 °C, 574.2 rpm, and 22.5 min as the optimal stir casting parameters for temperature, speed and time respectively.

Chrysophyllum albidum fruit ethanol extract ameliorates hyperglycaemia and elevated blood pressure in streptozotocin-induced diabetic rats through modulation of oxidative stress, NF-κB and PPAR-γ.

Oxidative stress and inflammation arising from hyperglycaemia have been identified as important targets in mitigating hyperglycaemia-induced organ dysfunction in diabetics. Chrysophyllum albidum fruit is commonly consumed as fruit snacks because of its beneficial effects in diabetes management. This study aim to evaluate the protective mechanisms of Chrysophyllum albidum fruit extract (CAFE) in streptozotocin-induced rats involving attenuation of oxidative stress, nuclear factor-kappa B (NF-κB) and peroxisome proliferator-activated receptor-gamma (PPAR-γ). CAFE was investigated for in vitro antioxidant and alpha amylase inhibitory activity. Male Wistar rats were made diabetic by single intraperitoneal injection of streptozotocin (60 mg/kg). The rats were then treated with CAFE (100 and 200 mg/kg) and pioglitazone (10 mg/kg) for two weeks. Fasting blood sugar (FBS), blood pressure parameters, lipid profile, oxidative stress parameters, NF-κB and PPAR-γ were determined. The extract showed antioxidant and alpha amylase inhibitory activities. CAFE significantly reduced STZ-induced hyperglycaemia after 7 and 14 days of treatment. CAFE also reduced STZ-induced elevation of diastolic blood pressure and mean arterial pressure and as well reduced atherogenic index in diabetic rats. It significantly decreased lipid peroxidation but increased the enzymatic and non-enzymatic antioxidant markers in the plasma, liver, kidney and pancreas. The immunohistochemical analysis revealed that CAFE significantly decreased hepatic and renal tissues NF-κB while increasing PPAR-γ gene expressions. The results of this study collectively showed the protective effect of Chrysophyllum albidum fruit extract in streptozotocin-induced diabetic rats via modulation of oxidative stress and NF-κB/ PPAR-γ expressions.

Hybridization of Selected Nigerian Lignocellulosic Biomass Feedstocks for Bioethanol Production: Modeling and Optimization of Pretreatment and Fermentation Process Parameters Using Response Surface Methodology.

In this study, hybridized feedstocks (mixtures of biomass) of cassava peels plus yam peels, as well as corn cobs plus rice husks biomass, were optimized using the response surface methodology centered on the statistical design of experiments (DOE) of the Box-Behnken design (BBD), to produce bioethanol. The feedstocks were locally sourced, hybridized (mixed), pretreated, and fermented before being distilled in a UOP3CC continuous distillation column. The BBD was applied using a 3-level, 3-factor process variables using pH, time, and particle size, and indicated as X1, X2, and X3, respectively. The bioethanol yield from the two hybridized biomass feedstocks was predicted by the developed quadratic polynomial models from BBD. For the hybridized biomass mixture of cassava peels plus yam peels, the optimal condition was statistically predicted as pH 5.00, fermentation time of 120.00 hours, and particle size of 362.5 microns, the predicted bioethanol yield under the optimal condition was 115.75 mL per 1500 g of hybridized biomass and the average volume of bioethanol obtained was 125.00 mL per 1500 g of biomass, which is within the projected range of the model equation, same applies to rice husks plus corn cobs hybridized biomass, but with a better prospect for bioethanol production.

Fabrication and characterization of keratin starch biocomposite film from chicken feather waste and ginger starch.

The disposal of chicken feather through burning or burying is not environmentally compliant due to the accompanying release of greenhouse gas and underground water contamination. Thus, the transformation of this bio-waste into a bio-composite film is considered not only a sustainable strategy for disposal of this solid wastes but also an attractive alternative to developing an efficient nanostructured biomaterial from renewable bio resource. In the present study keratin extracted from chicken feather waste in combination with ginger starch were fabricated into a bio-composite film. The fabricated bio-composite films were characterized, using different analytical techniques. The physicochemical characteristics of ginger starch showed a moisture content of 33.8%, pH of 6.21, amylose and amylopectin contents of 39.1% and 60.9%, respectively. The hydration capacity of the starch was 132.2% while its gelatinization temperature was 65.7 °C. Physical attributes of the bio-composite film, such as surface smoothness and tensile strength increased significantly (p < 0.05) with increasing keratin content, while its transparency and solubility showed significant (p < 0.05) decrease with increasing keratin level. The various blends of the bio-composite films decayed by over 50% of the original mass after 12 days of complete burial in soil. Based on the results obtained in this study, the addition of keratin to starch bio-composite showed remarkable improvement in mechanical properties, such as tensile strength and surface smoothness. The bio-composite film exhibited appropriate stability in water, although future study should be carried out to evaluate its thermal stability. Nonetheless, the fabricated keratin-starch bio-composite showed desirable characteristics that could be optimized for industrial applications.

Experimental evaluation of bamboo fiber/particulate coconut shell hybrid PVC composite.

Bamboo fibers (BF) treated in 1.3 Molar NaOH and particulate coconut shell (PCS) sieved to - 45 µm were incorporated into polyvinyl chloride (PVC) matrix towards improving the properties of PVC composite for ceiling boards and insulating pipes which sags and degrade with time needing improvement in properties. The process was carried out via compression moulding applying 0.2 kPa pressure and carried out at a temperature of 170 °C. Composites developed were grouped according to their composition. Groups A, B, C, and D were infused with 2, 4, 6 and 8 wt% PCS at constant amount, respectively. Each group was intermixed with a varying proportions of BF (0-30 wt% at 5% interval). Tests carried out on the samples produced revealed that the yield strength, modulus of elasticity, flexural strength, modulus of rupture were enhanced with increasing BF proportion from 0 to 30 wt% BF at 2 wt% constant PCS input. Thermal and electrical properties trended downward as the fiber content reduced even as the hardness was enhanced with PCS/BF intermix which was also reflected in the wear loss index. Impact strength was highest on the infix of 4 wt% PCS and 15 wt% BF. Compressive strength was better boasted with increasing fiber and PCS amount but 8 wt% PCS amounted to depreciation in trend. It was generally observed that PCS performed optimally at 2 wt% incorporation while beyond that resulted in lowering of strength. Blending of the two variable inputs; 0-30 wt% BF and 2 wt% PCS presented better enhancement in properties.

Influence of alkaline modification on selected properties of banana fiber paperbricks.

In a bid to develop paper bricks as alternative masonry units, unmodified banana fibers (UMBF) and alkaline (1 Molar aqueous sodium hydroxide) modified banana fibers (AMBF), fine sand, and ordinary Portland cement were blended with waste paper pulp. The fibers were introduced in varying proportions of 0, 0.5, 1.0 1.5, 2.0, and 2.5 wt% (by weight of the pulp) and curing was done for 28 and 56 days. Properties such as water and moisture absorption, compressive, flexural, and splitting tensile strengths, thermal conductivity, and specific heat capacity were appraised. The outcome of the examinations carried out revealed that water absorption rose with fiber loading while AMBF reinforced samples absorbed lesser water volume than UMBF reinforced samples; a feat occasioned by alkaline treatment of banana fiber. Moisture absorption increased with paper bricks doped with UMBF, while in the case of AMBF-paper bricks, property value was noted to depreciate with increment in AMBF proportion. Fiber loading resulted in improvement of compressive, flexural, and splitting tensile strengths and it was noted that AMBF reinforced samples performed better. The result of the thermal test showed that incorporation of UMBF led to depreciation in thermal conductivity while AMBF infusion in the bricks initiated increment in value. Opposite behaviour was observed for specific heat capacity as UMBF enhanced heat capacity while AMBF led to depreciation. Experimental trend analysis carried out indicates that curing length and alkaline modification of fiber were effective in maximizing the properties of paperbricks for masonry construction.

Effect of Surface Modification on the Properties of Polypropylene Matrix Reinforced with Coir Fibre and Yam Peel Particulate.

Polypropylene composites reinforced with coir fibre and yam peel particulate were produced using compression moulding machine. Treated and untreated coir fibres were used; 1.5 M NaOH was used for the treated coir fibres. Yam peel was grouped into two, treated and untreated; the treated was modified using 1 M solution of NaOH and HCl in the proportion of 30% and 70%, respectively. The yam peel which was sun-dried for 14 days was pulverized and sieved to -45 µm. Samples were developed using treated and untreated reinforcements (TCF/YPP and UCF/YPP) at constant coir fibre proportion (15%) and varied amount of yam peel particulate (2, 4, 6, and 8 wt.%). The hybrid composite samples developed were probed for mechanical properties and thermal and wear behaviour. The level of particles agglomeration at the fibre-matrix interface was examined using scanning electron microscope. The results show that sample reinforced with treated 4 wt.% coir fibre and yam peel particulate had optimum mechanical properties. However, the thermal conductivity of composite samples increased with fibre addition. All composite samples developed had better resistance to abrasion when compared to the control sample.

Spinal Malignant Peripheral Nerve Sheath Tumours in Nigerians.

BACKGROUND: Spinal Malignant peripheral nerve sheath tumours (MPNSTs) are very rare aggressive tumours with poor prognosis. Little is known about these tumours in sub-saharan Africa. OBJECTIVES: This study aims to evaluate the clinical profile and outcome of management of these tumours in a resource limited country. METHODS: We retrospectively analysed data from the records of patients who had surgery for spinal MPNSTs at our center between January 2004 and December 2018. RESULTS: There were four patients in this study (M:F= 1:1). The ages ranged from 27-53 years with a mean of 43.25 ± 11.84 years. The tumour was located in the thoracic region in 2 of the patients (50%), the lumbar region in one (25%) and thoracolumbar in the 4th patient. Three patients (75%) presented with back pain while limb weakness, sensory deficit and sphincteric dysfunction were present in all patients at presentation. The duration of symptoms were 2 months in 2 patients (50%) and 3 months in the other 2. None of the patients had neurofibromatosis. Gross total tumour excision was achieved in 2 patients (50%) and subtotal resection in the other 2. The tumours were high grade in three patients (75%) and low grade in one. Two patients had adjuvant radiotherapy. Two of the patients were dead within 6 months of the diagnosis, another one within 18 months while one patient is still alive 3 years after. CONCLUSIONS: MPNSTs are very rare in our practice. Most of the tumours were high grade tumours and ran an aggressive course.

Experimental determination of the effects of pretreatment on selected Nigerian lignocellulosic biomass in bioethanol production.

In the present study, five lignocellulosic biomass namely, corn cobs (Zea mays), rice husks (Oryza sativa), cassava peels (Manihot esculenta), sugar cane bagasse (Saccharum officinarum), and white yam peels (Dioscorea rotundata) of two mesh sizes of 300 and 425 microns and a combination of some and all of the biomass were pretreated using combined hydrothermal and acid-based, combined hydrothermal and alkali-based and hydrothermal only processes. The raw and pretreated biomass were also characterized by Fourier transform infrared spectroscopy (FT-IR), Brunauer-Emmett-Teller (BET), X-Ray diffraction (XRD), and Scanning electron microscopy (SEM) to determine the effects of the various pretreatments on the biomass being studied. The cellulose values of the raw biomass range from 25.8 wt% for cassava peels biomass to 40.0 wt% for sugar cane bagasse. The values of the cellulose content increased slightly with the pretreatment, ranging from 33.2 to 43.8 wt%. The results of the analysis indicate that the hydrothermal and alkaline-based pretreatment shows more severity on the different biomass being studied as seen from the pore characteristics results of corn cobs + rice husks biomass, which also shows that the combination of feedstocks can effectively improve the properties of the biomass in the bioethanol production process. The FTIR analysis also showed that the crystalline cellulose present in all the biomass was converted to the amorphous form after the pretreatment processes. The pore characteristics for mixed corn cobs and rice husks biomass have the highest specific surface area and pore volume of 1837 m2/g and 0.5570 cc/g respectively.

Antihypertensive effect of Phragmanthera incana (Schum) Balle on NG-nitro-L-Arginine methyl ester (L-NAME) induced hypertensive rats.

ETHNOPHARMACOLOGICAL RELEVANCE: Phragmanthera incana (Schum) Balle is a member of the African mistletoes that has been reported to be used in ethnomedicine for the treatment of hypertension. AIM: The aim of this study was to investigate the antihypertensive effect of Phragmanthera incana leaf ethanol extract (PILEE) in NG-nitro-L-arginine methyl ester (L-NAME)-induced hypertensive rats. MATERIALS AND METHODS: Phytochemical analysis of PILEE was determined using the Gas chromatography - Mass spectrophotometry (GC-MS) method. Antihypertensive activity was investigated in rats that received PILEE (50, 100 and 200 mg/kg) or captopril (40 mg/kg) daily for 28 days together with oral administration of L-NAME (40 mg/kg). Blood pressure parameters were measured on day 7, 14, 21 and 28. Blood was obtained for determination of serum nitrite, interleukin-6 (IL-6) and tumor necrosis factor, TNF-α. The heart, liver and kidneys were used to determine oxidative stress indices (malondialdehyde, reduced glutathione and catalase). The cardiac tissue was processed for histopathological changes. RESULTS: The GC-MS profiling of PILEE identified 20 compounds namely fatty acid esters. Administration of PILEE (50, 100 and 200 mg/kg) dose dependently and significantly reduced systolic blood pressure and mean arterial pressure in hypertensive rats. PILEE administration significantly (p < 0.05) reversed elevated IL-6 and TNF-α in hypertensive rats. PILEE demonstrated antioxidant activity by attenuating L-NAME-induced elevated malondialdehyde and depletion of reduced glutathione and catalase activity in rat tissues. PILEE treatment demonstrated cardioprotective effect in L-NAME-induced cardiac hyperplasia and necrosis in rats. CONCLUSION: It can be concluded that Phragmanthera incana leaf ethanol extract possess antihypertensive, antioxidant and anti-inflammatory properties, suggesting a protective role in cardiovascular diseases.

Pericallosal artery aneurysm - Case report, literature review and management outcome.

INTRODUCTION: Pericallosal artery aneurysms are rare. Very few cases of this vascular anomaly have been published from West Africa. We report the first case of a ruptured pericallosal artery (PCA) aneurysm managed in a Nigerian neurosurgical facility, with the aim to add to the limited documentation on vascular brain lesions in our sub-region. The management outcome of the index patient and a literature review on these unusual aneurysms were also discussed. CASE REPORT: A middle-aged known hypertensive woman who presented with clinical features of a WFNS grade I subarachnoid hemorrhage (SAH). A plain cranial computerized tomography (CT) scan revealed SAH, a supracallosal intracerebral hematoma and intraventricular hemorrhage. Cranial computerized tomography angiography (CTA) showed a small right pericallosal artery aneurysm, which was treated (with clipping via an interhemispheric approach) in a resource-constrained neurosurgical facility. The patient has remained well over a six-year follow-up period. DISCUSSION: PCA aneurysms have a high tendency to bleed compared with other supratentorial intracranial aneurysms in spite of their small size. Microsurgical approach, although difficult, is an effective treatment option for these rare aneurysms. CONCLUSION: Surgical clipping remains a safe and useful treatment option for pericallosal artery aneurysms in a low-resource neurosurgical facility.