Annual Research & Review in Biology

Several studies on the adverse effects of methotrexate have been reported, especially its implication in the degeneration of spermatogenesis, reduced sperm count and ultimate male infertility. As an antagonist, methotrexate (MTX) uses folic acid to obstruct the production of some biomolecules involved in synthesis of DNA, RNA and protein. It is used in the treatment of cancer and other diseases such as psoriasis, and rheumatism. Reports have also revealed that the expression of Bone Morphogenetic Protein (BMP8a) promotes spermatogenesis and fertility through the induction and activation of signaling sets of transcription factors, SMAD1/5/8. Hence, the expressions of these proteins and role of apoptosis are crucial to understand the mechanism involved in Methotrexate-induced infertility. In view of this, albino mice (Swiss strain) were randomly sorted to four groups. Group I served as control while groups II, III & IV (n=5) were treated with 5, 10 and 20mg/kg/day of Methotrexate (IP) respectively. Expressions of BMP8A and SMADs 1/ 5/ 8 were done by PCR and Western blotting techniques. Germ cell apoptosis was measured by flow cytometry and immunohistochemistry techniques. Ultrastructural changes were assessed in leydig cells as well as sertoli cells. The results of this study reveal a down-regulation of BMP8A and SMAD1/5/8 proteins in a dose-dependent pattern. Induction of apoptosis was also confirmed by the expression of primary apoptotic Bax antibody. The sertoli cells which play their major roles of nourishing and protecting the development of sperm cells were severely impaired too. These findings suggest that the function of BMP8A and SMAD1/5/8 proteins in promoting proliferation and differentiation of spermatogonia was severely disrupted following methotrexate exposure. Caution should therefore be taken when administering this drug.

Introduction: Urinary tract infection is a major reason for hospital visits and a common clinical condition encountered by clinicians. The causative agents of urinary tract infection and their resistant pattern vary globally. The aim of this study was to highlight the profile of pathogens associated with urinary tract infections in our locality. The objective was to investigate the resistant pattern of these microbial isolates from patients with urinary tract infection and offer recommendations for effective treatment.

Materials and methods: We retrospectively analyzed the urine culture and antimicrobial sensitivity reports of patients with suspected urinary tract infection at the University of Calabar Teaching Hospital, Calabar, Nigeria, from September 2019 to August 2020. Methicillin resistance was detected by disk diffusion method using 30 µg cefoxitin disk. Production of Extended spectrum beta lactamases was detected by the Combination disk and the double-disk synergy method.

Results: Of 979 urine culture and sensitivity reports, 306 (31.26%) were positive for microbial growth. Two microbial isolates each were recovered from urine samples of 5 patients giving a total number of 311 isolates from 306 patients. 45.75% of positive results were in males. The predominant isolate was Escherichia coli (n=97, 31.19%). Extended Spectrum Beta Lactamases (ESBL) producing strains comprised 10.08% (10/238) of Gram-negative group of organisms, while 47.39% (145/306) of all bacterial isolates in our study were multi drug resistant (MDR). 14.29% (6/42) of S. aureus isolates were methicillin resistant S. aureus, while 33.33% (2/6) of methicillin resistant S. aureus (MRSA) were multi drug resistant.

Conclusion: Urinary tract infection caused by antimicrobial resistant organisms is common among studied patients. This emphasizes the need for urine culture and sensitivity tests in the management of urinary tract infection.

Objective: The effects of 6-MSITC on cell cycle progression were investigated in quiescent mouse epidermal JB6 cells.

Background: 6-Methylsulfinylhexyl isothiocyanate (6-MSITC) derived from wasabi (Wasabia japonica) has been reported to prevent tumor development in vivo.

Material and methods: Treatment with epidermal growth factor (EGF) to quiescent JB6 cells, which were serum-starved for 36 h, promoted cell cycle progression from the G₀/G₁ phase to the S phase. Effects of pretreatment with 6-MSITC on cell cycle progression were estimated by flowcytometry and real-time RT-PCR.

Results: Pretreatment with 6-MSITC at 0.25-1.0 μg/ml prior to the growth stimulation with EGF significantly inhibited cell cycle progression. Pretreatment with 6-MSITC inhibited the gene expression of DNA synthesis-related proteins cyclin A2, dumbbell former 4, and proliferating cell nuclear antigen.

Conclusion: These results showed that 6-MSITC inhibits cell cycle progression in quiescent cells, accompanied by the inhibition of gene expression of DNA synthesis proteins.

Polygonatum humile Fisch is commonly called Sookjuk in Korea. The roots of P. humile are typically used in traditional medicine as an anti-rheumatic, demulcent, and sedative agent. The aim of this study was to evaluate the potential of the P. humile extracts to treat depression. Mice were administered P. humile water extract (PH) and were subjected to the forced swim test (FST), tail suspension test (TST), and open-field test (OFT). The levels of brain monoamines including serotonin (5-HT), norepinephrine, and dopamine were evaluated. In addition, the PH antidepressant-like effects were studied based on the regulation of 5-HT-mediated Ca²⁺ and extracellular signal-regulated kinase 1/2 (ERK1/2) in human 1321N1 cells stably expressing the 5-HT subunit 6 receptor (5-HT₆). In FST and TST, PH (300 mg/kg) significantly reduced the immobility time without changing the locomotor activity in mice. In addition, PH enhanced the level of 5-HT in the mice brain. The results further indicated an inhibitory activity of PH on both   the 5-HT₆ receptor expression level and the 5-HT₆ receptor dependent downstream signal   pathway ERK1/2.These findings indicated antidepressant-like effects of PH  as evidenced by decreased immobility time in mice through a 5-HT₆ receptor antagonistic mechanism.

Fungi play vital roles as decomposers. White rot fungi are an eco-physiological group that degrades wood by the secretion of specialized extracellular enzymes including lignin-modifying enzymes. There is growing interest in the use of extracellular enzymes for bioremediation. This study determined the Lignin Modifying Enzymes (LMEs) associated with two species of mushroom, Pleurotus ostreatus and Lentinus squarrosulus. The qualitative study was conducted using agar medium substituted with chromogenic substances to determine the production of LMEs by the species. The appearance of colour change and clearance due to reaction with chromogenic substrates were used to determine LMEs production by the fungi. The results showed that Pleurotus ostreatus and Lentinus squarrosulus tested positive by the appearance of light brown colouration, reddish-brown colouration and discolouration of media for overall polyphenol oxidase, Laccase and Peroxidase activity, respectively. The study showed that the species studied are candidates for large scale production of LMEs that can be utilized as an eco-friendly solution for bioremediation of contaminated sites.

Cucurbits are group of plants which belonged in the Cucurbitaceae family and constitute one of the most important vegetables for human consumption throughout the world. A survey conducted between January to March 2021 across major cucurbit-growing area in Cross River State revealed wide spread virus infection of these crops, surveyed plants showed mosaic, mottle and leaf deformation symptoms. This research was aimed at identifying viruses infecting some cucurbits in the study areas. Twenty four samples showing virus like symptoms were collected and tested against ACP-ELISA and RT-PCR. Result obtained from ACP-ELISA showed that 20 out of 24 samples collected tested positive to universal potyvirus antisera, the gene sequence analysis revealed that samples were predominantly infected with Algerian watermelon mosaic virus representing 40% of total viruses detected followed by Morroccan watermelon mosaic virus representing 15% of total viruses detected followed by Papaya ringspot virus, Zucchini tigre mosaic virus, Watermelon mosaic virus and Soybean mosaic virus representing 10% each for total viruses detected and finally Potato virus Y representing 5% of total virus detected. This survey is an accurate and timely detection and will form the basis for mitigating yield losses resulting from virus infection on cucurbits. This is the first report of wide scale detection of viruses infecting cucurbits in Nigeria.

Aim: Amelioration effect of soil amendment on growth and yield of Vigna unguiculata L. grown in acidic and alkaline soils.

Study Design: The study was conducted in a randomized complete block design with five replicates.

Place and Duration of Study: Department of Botany, University of Calabar, Nigeria, between May and September, 2017.

Methodology: Composite soils from two locations Akamkpa (pH 4.0) and Odukpani (pH 9.0) were collected, mixed thoroughly with organic manure (OM) and agricultural lime (AL) singly and in combination, allowed to stay three weeks for proper blending before V. unguiculata seeds were sown. On seedlings germination, amelioration effect of soil amendment on growth and yield of cowpea grown in acidic and alkaline soils was studied at different periods of growth.

Results: Results revealed significant (P=0.05) increase in leaf area, plant height, number of leaves, leaf fresh and leaf dry weight, relative growth rate, net assimilation rate and leaf area ratio of V. unguiculata grown in acidic and alkaline soils treated with OM and AL. Pod length, number of pods plant^-1, number of seeds pod^-1, number of seeds plant^-1, weight of 100 seeds increased significantly. Organic manure used singly and in combination was more effective in ameliorating soil pH effect than AL. Vigna unguiculata performed better in treated and untreated alkaline than in acidic soils. Least plant height for V. unguiculata grown in untreated alkaline soil at 12 weeks after sowing WAS was 60.22±0.16^a cm and highest 119.63E2±.35^g cm for plants grown in soil treated with AL₁+OM₁. Least number of seeds plant^-1 for plants grown in untreated acidic soil at 12 WAS was 90.60±0.02^a and the highest 139.18E2±0.02^e for plants grown in soil treated with AL₁+OM₁.

Conclusion: An improvement in growth and seed yield of V. unguiculata grown in acidic and alkaline soils is feasible through the use of organic manure and agricultural lime.

The article derives the probability for lethal recessive alleles in the case of recessive disadvantage or advantage. It is shown that recessive advantage of a lethal gene can be detected by the ratio of heterozygotes and homozygotes. This demonstrates that higher IQ of certain ethnic groups cannot be explained by recessive advantage of lethal genes. The article shows that lethal genes can survive in the population if some lineages of families have much more children than the average.

Background and Aims: The sylviculture of Pterocarpus erinaceus is still in its infancy due to lack of information on its biology. The aim of this study is to investigate its mycorrhizal status in order to better address its sylviculture.

Place and Duration of Study: The study was performed on the field from May 2019 to December 2020 and data were analyzed at the laboratory from January to March 2021.

Methodology: The frequency and intensity of mycorrhization were determined under a microscope after staining with trypan blue of fine roots collected at a depth of 20 cm under adult plants at 5 sites, 3 in the Guinean zone and 2 in the Sudanian zone in Togo. The spore density was obtained on soil samples taken at the same depth under the same trees.

Results: Results indicate, without significant differences (P value = 0.166) among sites, and show that P. erinaceus is frequently mycorrhized (88% to 94%). However, there were significant differences (P value = 0.001) in spore densities between sites located in the Sudanian zone (16.53 ± 1.25 and 10.66 ± 0.71 spores per gram of soil – SPGS – respectively for the Fazao-Malfakassa and Oti-Kéran-Mandouri) and those located in the Guinean zone (4.54 ± 0.3, 2.93 ± 0.43 and 3.76 ± 1.01 SPGS respectively at Abdoulaye, Hahomegbe and Togodo). There are significant differences between mycorrhization intensities Togodo which has a mycorhization intensity of 33.52 ± 2.54   and other sites. The redundancy analysis carried out by taking into account substrates’  chemical characteristics shows that spore density remains low when phosphorus and nitrogen are important in the rhizosphere whereas the intensity of mycorhizations is low when PH_KCl is high.

Conclusion: This study provided evidence of mycorrhizal symbiosis in Pterocarpus erinaceus whether in the Sudanian or Guinean zone. Chemical quality of the growing substrate has an influence on parameters of mychorization. Further studies should therefore allow an assessment of the degree of dependence of this species with respect to the possible benefits associated with this symbiosis.

Background: Cinnamomum cassia stem bark is used traditionally for the treatment of digestive disorders, diabetes and to alleviate symptoms of cold or flu.

Aim: The present study evaluated biochemical and haematological changes in male albino rats after exposure to the stem bark ethanolic extract of Cinnamomum cassia (SBECC).

Study Design: An experimental study which lasted for 19 days.

Place and Duration of Study: Department of Medical Laboratory Sciences and Animal House, College of Medicine, University of Nigeria, Enugu Campus, between April 2019 and August 2019.

Methodology: Twenty (20) rats weighing 130-170 g were used. Graded doses (100, 200 and 400mg/kg body weight) of the SBECC were orally administered to the animals in groups B, C and D respectively, once daily for 18 days. Group A served as the normal control and received only the vehicle (5ml/kg of 0.25N sodium carbonate). On Day 19, body weights of the rats were measured and blood samples obtained via retro-orbital puncture, were placed into plain tubes and tri-potassium ethylene diamine tetra-acetic acid (K₃EDTA) containers for biochemical and haematological studies respectively.

Results:  Weight gain was observed in all treatment groups and control. The highest and lowest percentage weight gain was observed in Group C (51%) and Group B (33%) respectively. All the doses of the extract significantly decreased serum cholesterol levels when compared to the control (P<0.05). Treatment with 400mg/kg SBECC (Group D) significantly increased serum Alkaline phosphatase (224.00±12.88iu/l) and creatinine levels (85.60±7.40) when compared to the control (140.00±26.47 and 63.60±7.60 respectively) (P<0.05), whereas treatment with 200mg/kg SBECC significantly increased urea and creatinine levels (P<0.05). No significant changes were observed in the haematological parameters of the treated rats compared to the control.

Conclusion: Sub-acute oral administration of Cinnamomum cassia stem bark extract at doses lower than 500 mg/kg may not exert toxic effects on haematological parameters but can alter some serum biochemical parameters in rats.