Abraham A.A. Osinubi

Antiovulatory and anti-implantation potential of the methanolic extract of seeds of Abrus precatorius in the rat.

OBJECTIVE To investigate the effect of the methanolic extract of seeds of Abrus precatorius on the estrous cycle, ovulation, and implantation of fetuses in Sprague-Dawley rats. METHODS Cyclic female rats were randomly classified into 4 groups (A through D). Treated rats in group A had daily vaginal smears for a total of 64 consecutive days while being fed A precatorius extract for the first 32 of those days. Treated rats in group B received a single oral dose of the extract on the day of proestrus and were killed the following morning so that shed ova could be counted. Treated rats in group C received A precatorius extract from postcoital day 1 to 10 and were killed on day 12 to assess for anti-implantation effect, whereas the treated dams in group D received the extract from the 6th to the 19th day of gestation. The control animals in all 4 groups received an equal volume of distilled water. RESULTS The methanolic extract of A precatorius caused a reversible disruption in the estrous cycle of the regularly cyclic rats and completely blocked ovulation in all the treated rats. Despite successful mating of the female rats with male rats of proven fertility, uterine dissection on postcoital day 12 revealed neither implantation nor resorption sites in all the animals treated with A precatorius. The extract of A precatorius caused a decrease in mean body weight, mean crown-rump length, and mean tail length of fetuses of the treated rats. CONCLUSION There is a need to continue the search for new antifertility agents that have minimal side effects and widespread acceptability in addition to being reversible, affordable, and accessible. In this study, methanolic extract of A precatorius seeds caused reversible alterations in the estrous cycle pattern and completely blocked ovulation in Sprague-Dawley rats. In addition, the extract demonstrated anti-implantation activity and the potential to affect gross fetal morphometry in rats.

Curcuma Longa: Staining Effect on Histomorphology of the Testis

Curcuma Longa: Staining Effect on Histomorphology of the Testis Background: The use of non-allergic, non-toxic and eco-friendly natural dyes has become a matter of significant importance due to the increased environmental awareness in order to avoid some hazardous synthetic dyes. Method: The ethanolic extract of Curcuma longa was diluted using 1% acetic acid in 70% ethanol to a concentration of 0.2 g/ml. It was used to stain histological sections of the testes for 15 minutes. Curcuma longa was also used as a counter stain for Haematoxylin. Phytochemical constituents were investigated. Results: The Curcuma longa dye distinctly stained the seminiferous epithelium and interstitium yellow. Curcuma longa provided a good counter stain for Haematoxylin, taking up the acidic staining characteristics with Haematoxylin staining the basic staining characteristics. Phytochemical screening revealed the presence of saponins, alkaloids, tannins and flavonoids. Conclusion:Curcuma longa has good potential for use as a counter stain for Haematoxylin in the staining of tissues in lieu of Eosin.

A Paradigm Shift in Medical, Dental, Nursing, Physiotherapy and Pharmacy Education: From Traditional Method of Teaching to Case-Based Method of Learning- A Review

Background: The most commonly used pedagogy in Nigeria and most other countries is the didactic method of teaching. This method is useful for covering underlying concepts, principles and systems. The traditional method of teaching places the burden of promoting learning fully on the teacher, unless it is integrated with other techniques such as problembased learning and case-based learning (CBL). However, the advantages of CBL over the traditional method of teaching have not been adequately evaluated and this also reflects on the dearth of available literature in this area. Aim: The purpose of this paper is to critically evaluate, analyze and synthesize the available literature evidence base about CBL in order to highlight its merits/benefits, barriers and possible shortcomings so as to guide Medical Colleges and Faculties of Pharmacy in Nigeria in taking a decision on whether or not to begin to explore the possibility of introducing CBL in their medical, dental, physiotherapy, nursing and pharmacy curricula. Methods: The study was literature-based. The review was focused on CBL for both preclinical and clinical health professional programmes including Medicine, Dentistry, Physiotherapy, Nursing and Pharmacy. Papers were required to have outcome data on Review Article Annual Research &Review in Biology, 4(13): 2053-2072, 2014 2054 effectiveness. The search covered the period from January 1990 to December 2013 and the following databases: MEDLINE, EMBASE, Cochrane Library, International Education Research Database, Web of Knowledge (WoK) and ERIC (Educational Resources Information Center) database. Results: The traditional modes of teaching of science and medical subjects focus mainly on the transmission of content by disciplinary experts. By nature, these teaching processes by themselves are not effective at equipping the students in the areas of communication, critical thinking, creativity, self-directed and collaborative learning. CBL adequately addresses most of these deficiencies in pedagogy. In their effort to find solutions and reach decisions through discussion, learners sort out factual data, apply analytic tools, articulate issues, reflect on their relevant experiences, and draw inferences they can relate to new situations that are often not given within the scope of a lecture but that could be very vital in professional practice. In the process, they acquire substantive knowledge, become innovative and develop analytic, collaborative and communication skills. Conclusion: Colleges and faculties of Medicine and Pharmacy should consider the inclusion of CBL in their curricula for the teaching of medicine, dentistry, physiotherapy, nursing, pharmacy and other allied programmes.

Histomorphometric studies of the effects of Telfairia occidentalis on alcohol-induced gonado-toxicity in male rats

Background Available evidence suggests that 50% of couples with infertility are male related. Over 40% of these males consume alcohol which has been reported to be a reproductive toxicant causing depletions in the epithelium of seminiferous tubules hence reducing sperm counts and sperm morphology. Objective To determine the effects of aqueous leaf extract of Telfairia occidentalis on alcohol-induced cyto-architectural changes in the testis. Methods Aqueous leaf extract of Telfairia occidentalis (T. occidentalis) was administered by gastric gavage at a dose of 250 mg/kg and 500 mg/kg body weight daily, while 2 g/kg body weight of ethanol at 30% v/v was administered daily to mature male Sprague–Dawley rats. The experiment was in 2 phases. Phase 1 had groups A1–F1 and lasted for 4 weeks while phase 2 had groups A2–F2 and lasted 8 weeks. Parameters tested include: testicular histology, relative volume density, sperm parameters, malondialdehyde (MDA), superoxide dismutase (SOD) and reduced glutathione. Results In both phases, there were depletions in the seminiferous epithelium, decreased sperm quality and increased MDA and SOD in animals that received alcohol only compared to control. Likewise, a significant increase of seminiferous epithelium of animals that received respective doses of 250 mg/kg and 500 mg/kg of T. occidentalis only compared to control. Animals that received T. occidentalis and alcohol simultaneously had a significant increase in seminiferous epithelium and sperm quality with decreased MDA level. Conclusion T. occidentalis attenuated the deleterious effects of alcohol to the cyto-architecture of the testis, protected the seminiferous epithelium, reduced oxidative stress and promoted spermatogenesis.

Staining effect of Hibiscus sabdariffa extract on sperm cell morphology of Sprague–Dawley rats

Abstract There is increasing awareness among people towards natural products. Due to their non-toxic properties, low pollution, and lower side effects, natural dyes are used in many day-to-day products. Although the African continent possesses plentiful plant resources, only a small amount has been exploited so far. This study evaluated the use of Hibiscus sabdariffa as a stain to evaluate sperm morphology. Following liquefaction, 10 μl of semen was spread onto glass slides and allowed to air-dry at room temperature. The smear was fixed for 15 minutes in methanol. The sperm morphology was analyzed by staining 10 slides of the smears with eosin (control) and the ethanolic extract of Hibiscus sabdariffa dye was used to stain the sperm cells. The smears were air-dried and viewed at magnification of ×400. Phytochemical and chromatographic analyses were carried out. The sperm cells were stained in shades of reddish brown. Preliminary phytochemical screening of Hibiscus sabdariffa revealed that it contains alkaloids, saponins, flavonoids, and tannins. Hibiscus sabdariffa has potential for use as a stain for study of sperm morphology.

Histological changes and testicular dysfunction in severely burned rats.

Histological Changes and Testicular Dysfunction in Severely Burned Rats Background: The immediate and early sequelae of burns such as vascular collapse and wound sepsis have been extensively studied. Some studies now show that burns cause significant changes in most body systems including the male reproductive system. Only few studies have addressed the reproductive consequences of burns in the male however. Objective: To delineate histologic changes induced in rat testes exposed to major burns. Setting: Medical School Anatomy department. Design: Experimental animal study. Materials & Methods: We induced 3rd degree burns in Wistar rats equivalent to 40% of total body surface area and observed them over several weeks. They were sacrificed at 8 and 16 weeks. Main Outcome Measures: Epididymal sperm parameters, serum FSH, LH and testosterone (T) were measured. A semi-quantitative evaluation of histo-pathological changes in the testis was also carried out. Results: Burns caused significant reduction in all sperm parameters (p<0.05). FSH, LH and T were also significantly reduced at 8weeks. By 16 weeks however, only T was still reduced. The key histologic change was germ cell atrophy. In cases with chronic wounds, sloughing left only basal cells such as spermatogonia and Sertoli cells in many tubules. Conclusion: Burns impair spermatogenesis and damages testicular histology in rats.

Effect of the juice of lime (Citrus aurantifolia) on estrous cycle and ovulation of Sprague-Dawley rats.

OBJECTIVE To determine the effect of lime juice on the estrous cycle and ovulation of cyclic female rats. METHODS Twenty-five adult female Sprague-Dawley rats were used. The study was divided into 2 experiments (I and II). In experiment I, 15 rats were randomly subclassified into 3 groups (Ia, Ib, and Ic) of 5 rats each. The estrous cycles of the rats were studied for the first 16 days to establish cyclicity, after which lime juice was administered by gastric gavage for the next 24 days. Rats in group Ia received 1 mL of undiluted lime juice, rats in group Ib received 1 mL of 50% diluted lime juice, and rats in group Ic (control animals) received only distilled water. In experiment II, 10 female rats were used and were categorized into 2 groups (IIa and IIb), with 5 rats in each group. Rats in group IIa received 1 mL of undiluted lime juice during the morning of proestrus, and those in group IIb received only distilled water on the day of proestrus. The rats were killed the next day with use of chloroform anesthesia. The upper parts of the oviducts were excised and examined under the light microscope for assessment of the number of ova shed. RESULTS There was an irregular pattern in all phases of the estrous cycle of 100% of the rats given undiluted lime juice and in 80% of those given 50% diluted lime juice. There was a significant (P = .001) reduction in the number of ova shed in rats administered undiluted lime juice in comparison with the control animals. Ovulation was partially blocked, as shown by the reduced number of ova observed in the oviducts from the rats given undiluted lime juice (5.10 +/- 2.37) in comparison with the control rats (12.70 +/- 1.14). CONCLUSION In rats, lime juice causes irregularity of the estrous cycle, partially blocks ovulation, and may possibly compromise fertility.

A comparison of the anti-diabetic potential of d-ribose-l-cysteine with insulin, and oral hypoglycaemic agents on pregnant rats

Graphical abstract

Quinine inhibits ovulation and produces oxidative stress in the ovary of cyclic Sprague-Dawley rats

Background Quinine has been reported to possess anti-spermatogenic activities. Objectives This study was carried out to determine the effect of quinine on ovarian function in Sprague-Dawley rats. Methods Twenty rats with regular 4-days oestrous cycle divided into 4 groups (N=5) were used. Group I received quinine at 30 mg/kg body weight by gavage for 28 days after which they were sacrificed. The ovaries were excised for biochemical oxidation of glutathione peroxidase (GSH), superoxide dismutase (SOD), catalase and malondialdehyde (MDA). Group II received single dose quinine at 30 mg/kg body weight at 0900 hrs on day of proestrus. Blood was obtained at 1800 hrs for hormonal assay of FSH and LH. The animals were sacrificed the next morning on estrus: oviducts were examined for ova count. Groups III and IV served as controls. Results Quinine treated rats recorded zero number of ova compared to control. Serum concentration of LH reduced significantly in the quinine treated group compared to the control. Furthermore, quinine significantly decreased the oxidant status of GSH, SOD and catalase and significantly increased MDA levels in the ovary compared to the control group. Conclusion Quinine completely blocks ovulation, suppresses LH surge, and produces oxidative stress in the ovary.

Factors influencing extract of Hibiscus sabdariffa staining of rat testes

Abstract Some plant extracts can be used in biology and medicine to reveal or identify cellular components and tissues. We investigated the effects of time and concentration on staining of histological sections of rat testes by an acidified extract of Hibiscus sabdariffa. An ethanolic extract of H. sabdariffa was diluted using 1% acetic acid in 70% ethanol to stain histological sections of testes at concentrations of 0.2, 0.1 and 0.05 g/ml for 5, 10, 15, 30, 45 and 60 min. The sections of testes were stained deep red. The staining efficiency of H. sabdariffa was greater at a high concentration and required less time to achieve optimal staining. H. sabdariffa is a strongly basic dye that can be used for various diagnostic purposes. Staining time and concentration must be considered to achieve optimal results.