Optimization of dual slot antenna using floating metallic sleeve for microwave ablation.

Backward heating reduction is vital in power distribution optimization in microwave thermal ablation. In this study, we optimized dual slot antenna to yield reduction in backward heating pattern along the antenna shaft with the application of floating metallic sleeve. Finite element methods were used to generate the electromagnetic (EM) field and thermal distribution in liver tissue. The position of the sleeve from the tip of the probe (z = 0 mm) was varied within the range 14 ≤ z ≤ 22 mm while sleeve length was varied within 16 ≤ z ≤ 48 mm at 2 mm interval using operating frequency of 2.45 GHz. The best optimized design has reflection coefficient of -20.87 dB and axial ratio of 0.41 when the sleeve position was at 17 mm and sleeve length was 18 mm. Experimental validation shows that inclusion of a floating metallic sleeve on dual slot antenna for hepatic microwave ablation averagely increased ablation diameter and aspect ratio by 17.8% and 33.9% respectively and decreased ablation length by 11.2%. Reduction in backward heating and increase in power deposition into liver tissue could be achieved by using this antenna to provide greater efficiency and localization of specific absorption rate in delivering microwave energy for hepatic ablation.

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.

Factors influencing extract of Hibiscus sabdariffa staining of rat testes.

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.

Assessing the risk of birth defects associated with exposure to fixed-dose combined antituberculous agents during pregnancy in rats.

Due to the risks of disease progression and transmission to the newborn, treatment of tuberculosis is often pursued during pregnancy and fixed-dose combined antituberculous agents have been found to be beneficial. Unfortunately, there is paucity of data on the safety of the fixed-dose combined antituberculous drugs during pregnancy. This study intends to assess the teratogenic effect of fixed-dose combined antituberculous drugs on the organogenesis stage of fetal development and also investigate the possible roles of vitamin C in modulating the teratogenic effects of these agents on the fetus using animal model. Pregnant rats were divided into 3 groups with 12 animals per group: group 1 received distilled water (10 mL/kg) orally; group 2 received 51.4 mg/kg/day of fixed-dose combined antituberculous agents orally; group 3 received 51.4 mg/kg/day of fixed-dose combined antituberculous agents plus vitamin C (10 mg/kg/day) orally. Six rats in each group were randomly selected and sacrificed on day 20 by cervical dislocation prior to day 21 of gestation, and the foetuses were harvested through abdominal incision for physical examination. Blood samples were collected from the 1st filial rats of the remaining six animals for biochemical and hematological examination. The liver, kidney, heart, and brain of all the sacrificed animals were used for histopathological examination. There were significant (P ≤ 0.05) low birth weights of the foetuses of the animals that were treated with fixed-dose combined antituberculous agents. The haematological parameters also revealed a reduction in the platelets counts and neutrophiles at the first filial generation. Significant (P ≤ 0.05) elevations in the levels of aspartate aminotransferase (AST) and alkaline phosphatase (ALP) in the foetuses of the animals treated with fixed-dose combined antituberculous agents were also observed. However, the combination of vitamin C with fixed-dose combined antituberculous agents significantly (P ≤ 0.05) reduced the level of AST. Fixed-dose combined antituberculous agents have teratogenic potential as shown in low birth weight and mild liver damage in the first filial of the treated animals. As much as it is imminent to treat TB patients in pregnancy, there is need to always exercise caution and clinically weigh the risk-benefit ratio.

Palliative effect of Pausinystallia macroceras on testicular ischemic reperfusion injury in Wistar rats: a histological study / Efecto paliativo de Pausinystallia macroceras sobre la lesión testicular por isquemia-reperfusión en ratas Wistar: un estudio histológico

Testicular torsion is a disorder involving the scrotum that results in a compromise of its blood supply. The aim was to investigate the effect of Pausinystallia macroceras (PM) on testicular histology following torsion-detortion at different time intervals ranging from 1 to 4 hours 65 mature male Wister rats allotted randomly into seven groups (A to G; E& F further divided into 4-subgroups). Each group/subgroup comprised 5 rats. Testis maintained in the torted position (T) for 1, 2, 3 and 4 hours in Groups A (AT1+PM), B (BT2+PM), C (CT3+PM) and D (DT4+PM). Group E subgroups (E1+PM, E2+PM, E3+PM, E4+PM -) were sham operated, without torsion served as the sham control. Group F subgroups (F1T1, F2T2, F3T3 and F4T4) were torted as in A. All animals (except groups F & G) treated with PM extract (0.1 g/kg.b.w/day) for 56 days. Group G rats (normal control). Testes processed for histological studies. In AT1+PM showed preserved seminiferous tubules. BT2+PM, revealed varying number of necrosed and apoptotic seminiferous tubules. Group CT3+PM rats were similar to BT2+PM although with a slightly higher proportion of seminiferous tubules had undergone necrosis. In DT4+PM, sections showed few viable spermatozoa within the seminiferous tubules. When compared to the torted group F; showed extensive areas of seminiferous tubular necrosis (F3T3) as well as damage to the interstitium; while in F4T4 there were no viable testicular tissues seen. In conclusion, PM significantly prevented the cellular changes and cell death observed especially in group AT1+PM and BT2+PM.

La torsión testicular es un trastorno que involucra el escroto resultando en un compromiso del suministro sanguíneo. El objetivo fue investigar el efecto de Pausinystallia macroceras (PM) en la histología testicular tras torsión-detorsión a intervalos de tiempo diferentes que van desde 1 a 4 horas en 65 ratas macho Wistar maduras, asignando aleatoriamente en siete grupos (desde A a G, mientras que E y F se dividieron en 4 subgrupos). Cada grupo/subgrupo estuvo compuesto por 5 ratas. Los testículos se mantuvieron en posición torsionada (T) durante 1, 2, 3 y 4 horas en los grupos A (AT1 + PM), B (BT2 + PM), C (CT3 + PM) y D (DT4 + PM). El grupo E, subgrupos (E1 + PM, E2 + PM + PM E3, E4 + PM) fueron operados por modelo sham sin torsión, que sirvió de control. El grupo F, subgrupos (F1T1, F2T2, F3T3 y F4T4) fueron torsionados como en A. Todos los animales (excepto los grupos F y G) fueron tratados con extracto de AM (0,1 g/kg peso corporal/día) durante 56 días. El grupo G fueron ratas control (control normal). Los testículos fueron procesados para el estudio histológico. En AT1 + PM se observó preservación de los túbulos seminíferos. BT2 + PM, reveló un número variable de túbulos seminíferos con necrosis y apoptosis. El grupo de ratas CT3 + PM fue similar a BT2 + PM, aunque un porcentaje ligeramente superior de los túbulos seminíferos mostraron necrosis. En DT4 + PM, los cortes mostraron pocos espermatozoides viables dentro de los túbulos seminíferos. En comparación con el grupo F torsionado mostró extensas áreas de necrosis tubular (F3T3), así como daños en el intersticio; mientras que en F4T4 no hubo tejido testicular viable. En conclusión, PM previno significativamente cambios celulares y la muerte celular observada, especialmente en el grupo AT1 + PM y BT2 + PM.

The antifertility effect of amodiaquine hydrochloride.

BACKGROUND: A number of antimalarial compounds and herbs have been reported to possess antifertility actions. Amodiaquine (AQ) belongs to the same class of drugs as chloroquine. Chloroquine has been reported to disrupt the oestrus cycle, block ovulation and consequently reduce fertility. OBJECTIVE: This study was carried out to investigate the effect of the administration of amodiaquine hydrochloride (AQ.HCl) on fertility in the adult cyclic Sprague-Dawley rats. METHODS: Thirty cycling female albino rats of Sprague-Dawley strain weighing 120 g were used in this experiment. They were divided into six experimental groups. Groups 1A, 1B and 1C- received peroral (p.o.) 6 mg/kg bw of AQ.HCl, 12 mg/kg bw of AQ.HCl and distilled water for 28 days respectively to determine the effect of AQ.HCl on the oestrous cycle. Groups 2A, 2B and 2C- received a single dose p.o. of 6 mg/kg bw of AQ.HCl, 12 mg/kg bw of AQ.HCl and distilled water at 9 a.m. on proestrus respectively to determine the effect of AQ.HCl on ovulation and the serum concentrations of follicle stimulating hormone (FSH), luteinizing hormone (LH) and prolatin (PRL). RESULTS: AQ.HCl disrupted the oestrous cycle by producing a significant (p < 0.05) increase in the diestrus phase and a reduction in the other phases when compared with the control. A significant reduction (p < 0.05) in the number of ova shed on estrus was observed however, there was no significant difference in the serum concentrations of FSH, LH and PRL when compared with the control. CONCLUSION: Oral administration of AQ.HCl distrupts the oestrous cycle and ovulation by increasing the frequency of the diestrus phase and reducing the number of ova released at ovulation respectively. These events may negatively affect fertility in females of reproductive age.

Effects of garcinia kola seed extract on ovulation, oestrous cycle and foetal development in cyclic female sprague-dawley rats.

The effects of Garcinia kola (G. kola) seed extract on oestrous cycle, ovulation and foetal development were studied in adult female Sprague-Dawley (S-D) rats. Cyclic female rats weighing 150 to 200 g were divided into three experimental groups and a control group. Group 1 was fed with 200 mg/kg body weight of the extract on proestrous. Group 2 received 200 mg/kg body weight of the extract daily for six weeks, while group 3, consisted of pregnant rats which received the same dose of the extract on days 1-5, 7-9 (th), 13 (th), and 14 (th), day of gestation. In groups 1 and 2, vaginal lavage was taken daily to monitor the oestrous cycle and ovulation. In group 3, gestational parameters monitored were number of total implants, resorption and dead foetuses. Live foetuses were weighed and examined for external malformation and variation. The results showed that the oestrous cycle was altered for the first two weeks after commencement of extract but returned to normal from the third week. This was indicated by the irregular pattern of oestrous with a prolonged dioestrus observed in the treated rats. Ovulation was partially blocked as shown by the reduced number of ova observed in the oviduct from the treated rats compared with control [P < 0.05]. There was a significant decrease in the weight of foetuses from the treated rats [P < 0.05]; while foetuses from pregnant rats (7 %) which received treatment for the first five days of gestation, had malformed left upper limb. Results suggest that G. kola seed at 200 mg/kg body weight administered alters oestrous cycle in rats, partly inhibits ovulation and may produce duration dependent teratogenicity in foetal rats.