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    MEDIATION OF HEXOSE TRANSPORT BY THE LIVER CELL MEMBRANE
    (1980-04) IBU, JOHN ODO
    1. Transport of D-glucose, D-galactose and D-fructose across the liver cell membrane was studied using an in situ rat isolated liver perfusion technique. 2. A bench-top liver perfusion apparatus which maintains the liver temperature constant for several hours of perfusion is described. This apparatus has the advantages that it is simple, cheap, and effective. 3. The perfusion medium used was Krebs bicarbonate buffer to which were added washed bovine erythrocytes and bovine albumin. This medium was found to meet the requirements for a viable liver perfusion. 4. Stringent viability criteria were adopted and livers which failed these criteria were rejected. Electron microscopic studies of perfused and unperfused livers were undertaken as adjunct to viability assessment of these livers. 5. The suitability of radioactively labelled sucrose as an extracellular reference material in a double indicator dilution technique in the perfused rat liver was investigated. 6. The hepatocellular transport of each of D-glucose, D-galactose and D-fructose was saturable. All the three hexoses showed mutual competition. The single pass extraction values for the hexoses were consistently different such that D-glucose>>D-galactose»D-fructose»»L-glucose. 7. D-glucose transport is by far greater than L-glucose transport suggesting stereospecificity of glucose transport mechanism, confirming the finding of the only previous study (WILLIAMS et al, 1968). 8. Both phlorizin and phloretin inhibited uptake of these hexoses. Of these two phloretin was by far the better inhibitor, a finding suggesting that the hepatic uptake of these sugars is analogous to known passive (e.g. human erythrocyte) rather than active (e.g. e.nterocyte) types of hexose transport. 9. Some dissaccharides were found to inhibit the uptake of these hexoses. Lactose inhibited the uptake of all three hexoses. Maltose inhibited uptake on D-glucose and D-fructose only (it had no effect on D-galactose uptake). Sucrose had no effect on any of the three hexoses. 10. Galactose transport was found to be temperature dependent. On an Arrhenius plot there was a discontinuity of this temperature dependence suggesting a transition temperature of about 31 C. A relatively high activation energy (67 Kj mole at 37°C) was calculated from these findings. 11. It was concluded, on the basis of the findings of saturability, competition, stereospecificity and greater chemical inhibition of hexose transport by phloretin than phlorizin, that these hexoses are transported across the liver cell membrane by a facilitated diffusion (carrier mediated) transport mechanism similar to that existing in human erythrocytes. On the basis of dissacharide effects, it was inferred that the D-galactose carrier mechanism is distinct at the external surface of the membrane from the D-glucose/fructose carrier mechanism. This implies an asymmetry between the external and internal carrier sites, the latter probably being common to all three hexoses whereas the former is distinct. An architecture for these carrier sites in the liver cell membrane is proposed
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    SYNTACTIC COMPLEXITY AND SENTENCE DECODING
    (1981-06) ALIYU, JOSEPH SUNDAY
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    BOVINE FETAL LUNG DEVELOPMENT
    (1985) HAMBOLU, JOSEPH OLAJIDE
    Fetal lung tissue obtained from abattoirs was examined histochemically using alpha-napthyl butyrate (nonspecific method), to defect the presence of pulmonary alveolar macrophages (PAM). Esterasepositive alveolar macrophages, which appear in the alveolar septa and lumina were first seen at 240 days of gestation. These macrophages were identified by the presence of numerous diffuse intensely red-stained granules in the cytoplasm. Macrophages at 240 days were 15.88 ± 1.67 Urn (S.E.) (N=30) in size and in most cells the esterase-positive granules were sparsely distributed in the cytoplasm. Only four out of eight lungs examined at 240 days were positive for alveolar macrophages. However, all the lungs (N=10) examined from 250=day-old fetuses contained esterase-positive macrophages, which were distributed both in the alveolar septa and alveolar spaces. Compared to macrophages of the 240-day fetuses, those at 250 days were signi ficantly larger, 16.91 ± 1.33 μm (S.E.) (N=30) (P<0.05). Type II pneumocytes and T lymphocytes were not confused with PAM because in all lungs, T lymphocytes contained a single, small, esterase-positive granule compared with the numerous diffuse esterase-positive granules in PAM while type II pneumocytes reacted negatively to nonspecific esterase stain during lung development. The time of appearance of alveolar macrophages coincides with the first appearance of surfactant at the alveolar surface-lining layer which suggests that macrophages could be involved with the clearing of excess surfactant being produced.
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    HAEMATOLOGY OF EXPERIMENTAL CONTAGIOUS CAPRINE PLEUROPNEUMONIA
    (1985-08) ALAFIATAYO, RUTH ABIMBOLA
    The haematological picture of contagious caprine pleuropneumonia (CCPP) induced in Savannah Brown (SB) goats using the virulent Smith's strain of Mycoplasma mycoides subsp capri was determined. In the first animal experiment, 10 adult SB goats were each inoculated intranasally with a total of 2.6 x 107 organisms contained in 5ml broth culture; 5 goats serving as controls received 5ml sterile broth intranasally, while another 4 goats were kept as stand-by to replace any goat that died of CCPP. The following haematologic parameters were determined 2 weeks and 1 week pre-inoculation, on day of inoculation (day 0), 3 days, 7 days, 11 days, 2 weeks, 3 weeks, 4 weeks, 6 weeks, 7 weeks, 8 weeks, 9 weeks 10 weeks, 12 weeks, 14 weeks, and 17 weeks postinoculation: Packed Cell Volume (PCV), Haemoglobin concentration (Hb), Total Red and White Blood Cell Counts (RBC and WBC), relative and absolute differential counts and total protein level. Some goats survived infection for only 1 week and this first study was terminated 17 weeks post-inoculation, providing data on both acute and chronic stages of CCPP,, In a repeat animal experiment, 6 SB goats received 1.0 x 101 0 organisms intranasally each, also in 5ml broth culture, and 4 goats received 5ml sterile broth culture as control. Unfortunatelyall infected goats died per-acutely or acutely within 7 days, such that the chronic blood picture could not be assessed, but these goats provided blood picture of a typical severe CCPP. Clinical signs of disease were observed and post mortem examination was carried out on all animals that died and on those killed at the termination of each study. Mycoplasma re-isolation attempts were made from the trachea and lungs of each goat, and lung sections were prepared routinely for histopathologic examinations. In animal experiment I, all infected goats showed elevated body temperature, coughing, inappetance, typical pleuritic sound on auscultation, and 3 died at 5 and 6 days post-inoculation. In animal experiment II, all infected goats showed similar clinical signs that were more marked and they died within 7 days post-inoculation, some as early as 48 hours post-inoculation. A mycoplasma confirmed by the growth-inhibition test as M. mycoides subsp. capri was isolated, from the trachea and lungs of all goats that died per-acutely or acutely, and from three goats killed 17 weeks post-inoculation. No mycoplasma was isolated from any control goat. Gross lesions observed in goats that died were of classical CCPP. They included heavy fibrinous deposits on lung and thoracic cage, pleural adhesions to pericardium and thorax, severe pericarditis and hydropericadium (about 30mls) and hydrothorax (about 200mls), darkened consolidation of all lobes of the right lung and the ventral side of the left diaphragmatic lobe, enlargement of the bronchial and mediastinal lymph nodes. Histologically, there was cellular infilteration of the alveoli, bronchioles and bronchi. Cells were mainly neutrophils, but there were some lymphocytes and plasma cells. A lot of fibrin strands infilterated the alveoli, bronchioles and the interlobular septae. There was vascular congestion, and dilation of the lymphatic vessels. The haematologic parameters were subjected to statistical analysis using the student t-test. Values of P 0.05 were considered significant. During the acute stage of infection, the mean values of total WBC counts, neutrophils and bands were higher in the infected goats than in control goats (P 0.05). This indicates a leukocytosis and neutrophilia with a regenerative left shift. During later stages, the values gradually returned to normal level, i.e. comparable to values from control goats or preinoculation data. On the other hand, PCV, Hb, RBC counts, and also total blood protein values were not significantly affected during CCPP (P>0.05). It is concluded that acute CCPP results in leukocytosis and neutrophilia with a regenerative left shift, but PCV, Hb, RBC and total protein values are not significantly affected. Moreover, the Smith's strain of M. mycoides subsp. capri is confirmed to be very highly pathogenic to Savannah Brown goats of Nigeria.
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    POSTNATAL DEVELOPMENT OF THE REPRODUCTIVE TRACT OF RED SOKOTO BUCKS
    (1986-05) BENJAMIN, NWABUEZE MARIRE
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    TYPHOID FEVER IN ZARIA.
    (1987-11) AKOH, J. A.
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    PHYTOCHEMICAL AND BIOLOGICAL INVESTIGATIONS ON GARDENIA SRUBESCENS STAFF & HUTCH
    (1988-01) HUSSAIN, M. MUSHARRAF
    G a r d e n i a erubescens Stapf & Hutch. (Rubiaceae) is l o c a l l y used for the t r e a t m e n t of gonorrhoea, impotence and s i m i l a r o t h e r a i l m e n t s . Phytochemical i n v e s t i g a t i on on the root l e d to the i s o l a t i o n of v a n i l l i c a c i d , d i o c t yl p h t h a l a t e , p - s i t o s t e r o l and D-raannitol i n c l u d i n g some u n i d e n t i f i e d compounds d e s i g n a t e d as CER1, CER2M, CER3, CAC, AGFM3, AGFM11, WB2 and a crude m i x t u r e of s a p o n i n s . An u n i d e n t i f i e d a l k a l o i d and an u n i d e n t i f i e d f l a v o n o i d pigment i n t r a c e q u a n t i t i e s have a l s o been i s o l a t e d . Stem b a r k and stem wood a l s o y i e l d e d s i m i l a r compounds. Mannitol has been found to be the major compound in a l l t h e p a r t s i n v e s t i g a t e d ( l e a f 5%, stem b a r k 3.4%, whole root 1.8%, stem wood 0.4% and f r u i t 0.25%). The sugars l i b e r a t ed upon h y d r o l y s i s of saponins were i d e n t i f i e d as g l u c o s e, a r a b i n o s e , xylose and g l u c u r o n i c a c i d . Glucose and f r u c t o se were d e t e c t e d as f r e e s u g a r s in the p l a n t. The crude s a p o n i n s , methanolic and w a t e r e x t r a c t s and some of the i s o l a t e d compounds were s c r e e n e d for v a r i o us b i o l o g i c a l a c t i v i t i e s using i n t a c t animals and i s o l a t ed t i s s u e s . The water e x t r a c t of the stem b a r k and aqueous s o l u t i o n of the i s o l a t e d mannitol produced mild d i u r e s i s in r a t s when given o r a l l y . The methanolic and water e x t r a c ts showed no in v i t r o a n t i b a c t e r i a l e f f e c t . The m e t h a n o l ic e x t r a c t and crude saponin s were shown to p o s s e s s low h a e m o l y t i c a c t i v i t y. The crude saponins c o n t r a c t e d the r a t u t e r u s , whereas t h e methanolic and water e x t r a c t s caused s l i g h t c o n t r a c t i o ns v i i a t higher c o n c e n t r a t i o n s ( 4 - 8 r a g / m l ) o n l y . Methyl v e r a t r a t e and compound CAC e f f e c t i v e l y a n t a g o n i s e d t he c o n t r a c t i l e e f f e c t s produced on the u t e r u s by a c e t y l c h o l i ne (40 - 80 ng/ml) and oxytocin (0,02 - 0,04 ng/ml) in a c o n c e n t r a t i o n - d e p e n d e n t and r e v e r s i b l e manner. Methyl v e r a t r a t e , crude s a p o n i n s , and m e t h a n o l i c and water e x t r a c ts a l l r e v e r s i b l y i n h i b i t e d the normal spontaneous c o n t r a c t i o ns produced by r a b b i t ileum in a dose-dependent manner. The r e s p o n s e s of r a b b i t ileum to a c e t y l c h o l i n e (80 ng/ml) were b l o c k e d c o n c e n t r a t i o n - d e p e n d e n t l y by methyl v e r a t r a t e. The crude s a p o n i n s , methyl v e r a t r a t e , compound CAC and m e t h a n o l i c e x t r a c t s i g n i f i c a n t l y i n h i b i t e d g r o s s b e h a v i o u rs of young mice and c h i c k s and caused dose-dependent s e d a t i o n. None of them produced any hypnosis in mice, although the crude saponins p o t e n t i a t e d the d u r a t i o n of t h e i r p e n t o b a r b i t o n e - induced s l e e p . The crude s a p o n i n s , b e t a - s i t o s t e r o l , methyl v e r a t r a t e and compound CAC slowed down i s o l a t e d p e r f u s ed r a b b i t h e a r t. The crude saponins and methanolic e x t r a c t showed no a n t i c o n v u l s a n t e f f e c t s in mice . T h e s e e x t r a c t s produced a l i t t le c o n t r a c t i l e e f f e c t on the frog r e c t u s abdominis muscle b ut d i d not produce any o b s e r v a b l e e f f e c t s on r a t v a s , The crude saponins e f f e c t i v e l y reduced the a n t i p s y c h o t i c behaviour in c h i c k s induced by apomorphine in a dose-dependent manner. The crude saponins and m e t h a n o l i c e x t r a c t produced d o s e - dependent a n a l g e s i a and c a t a l e p s y in a d u l t r a t s . They a l so reduced the blood p r e s s u r e of a n a e s t h e t i s e d c a t s . The Median L e t h a l Doses ( i n t r a p e r i t o n e a l ) of t he m e t h a n o l i c e x t r a c t and crude saponins were found to be 550 mg/kg and 119 mg/kg r e s p e c t i v e l y.
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    DRACUNCULIASIS IN SI X VILLAGES OF DAWAKIN-KUDU LOCAL GOVERNMENT AREA KANO STATE
    (1992-11) MUSA, MUSTAPHA DOGAR
    A s u r v e y of d r a c u n c u l l a s l s was c o n d u c t e d a mo ng humans and a n i m a l s In s i x v l l l a a e s of Dawaki n Kudu d i s t r i c t o f D a w a k i n - K u d u L o c a l G o v e r n m e n t A r e a , Kano 5 t a t e b e t w e en A p r l I , 1 9 9 0 to F e b u a r y , 1 9 9 1 . An o v e r a l l p r e v a l e n c e of 75 p e r s o n s p e r 100 0 ( 7 . 5 % ) was r e c o r d e d , w i t h G u n a k a v i l l a ge h a v i n q the h i g h e s t p r e v a l e n c e of 2 3 7 p e r s o n s per 1000 ( 2 3 . 7 % ) w h i l e F a g o j l had t h e l o w e s t , 7 p e r s o n s p e r 1000 ( 0 . 7 % ) . G r o u p of v i l l a g e s w i t h h a n d p u m p s has l o w e r p r e v a l e n c e , 4 8 p e r s o n s p e r 1 0 0 0 ( 4 . 8 % ) t h a n the q r o u p of vi l l a g e s w i t h o ut h a n d p u m p s w i t h a p r e v a l e n c e of 115 p e r s o n s p e r 1 0 0 0 ( 1 1 . 5 % . The a s s o c i a t i o n b e t w e e n l a c k of handpump and g u i n e a w o rm I n f e c t i o n was h i q h I y s i g n i f i c a n t ( P < 0 . 0 0 1 ) . The age s p e c i f i c p r e v a l e n c e I n the s i x v i l l a g es r e v e a l e d a n I n i t i a l I n c r e a s e o f I n f e c t i o n w i t h a g e r e a c h l nq a p e a k at t h e 3 r d a n d 4 t h d e c a d e of l i f e . The h i g h e s t p r e - v a l e n c e of 90 p e r s o n s p e r 100 0 ( 9 . 0 % ) was f o u n d a mong t he 2 0 - 2 9 y e a r a q e g r o u p . The d i f f e r e n c e In a s s o c i a t i o n was f o u n d t o be h l q h l y s i g n i f i c a n t ( P < 0 . 0 2 ) . T h e r e w e r e more c a s e s of g u l n e a w o r m a mo n g f a r me r s t h a n any o t h e r o c c u p a t i o n al g r o u p s I n a l l the v i l l a g e s . About 5 1 8 p e r s o n s p e r 1 0 00 ( 5 1 . 8 % ) w e r e f o u n d t o be p r e v i o u s l y I n f e c t e d n a l l the v i l - l a q e s . Of t h e 8 8 0 c u r r e n t c a s e s , 5 0 9 ( 5 7 . 8 % ) w e r e r e c u r r e n t c a s e s w h i l e 371 ( 4 2 . 2 % ) we r e h a v i n g t h e I n f e c t on f o r the f I r s t ti me . - V t I I — U s e r s of " R u g u z a I " / W e I I h a v e the h i g h e s t p r e v a l e n ce o f 3 2 8 p e r s o n s p e r 1 0 0 0 ( 3 2 . 8 % ) w h i l e t h e l o w e s t p r e v a l e n ce of 11 p e r s o n s p e r 100 0 ( 1 . 1 % ) was f o u n d a mong u s e r s of w e l l . T h o s e who d e p e n d e d ori " R u g u z a l " In c o m b i n a t i o n w i t h o t h er w a t e r s o u r c e s h a v e hi g h e r p o o l e d p r e v a l e n c e of 150 p e r s o ns p e r 1 0 0 0 ( 1 5 % ) t h a n t h o s e who d e p e n d e d on p o n d or h a n d p u m p In c o m b i n a t i o n w i t h o t h e r s o u r c e s w i t h a p o o l e d p r e v a l e n c e of 7 0 p e r s o n s p e r 1 0 0 0 ( 7 . 0 % ). Of the 8 8 0 I n f e c t e d I n d i v i d u a l s , 3 4 5 ( 3 9 . 2 % ) had o n l y one wor m e m e r g l n g w h i l e a b o u t 7 9 3 ( 9 0 . 1 % ) h a d the w o r m e m e r g l n g f r o m t h e l o w e r l i m b s . Of t h e 3 1 , 7 2 2 a n i m a l s e x a m i n e d o n ly 2 ( 0 . 0 0 6 % ) a n i m a l s w e r e f o u n d to be I n f e c t e d . About 2 1 , 5 9 5 m a n - d a y s w e r e l o s t due to gu i ne a w o rm Infection I n t h e s i x v i l l a g e s . When t h i s was t r a n s l a t e d I n t o the amount p a i d t o h i r e d l a b o u r i t a m o u n t e d t o n i n e h u n d r e d and s e v e n ty o n e t h o u s a n d s e v e n h u n d r e d and s e v e n t y f i v e N a i r a (N971,775). Of t h e 8 8 0 I n f e c t e d I n d i v i d u a l s , 1 7 ( 1 . 9 % ) w e r e d i s a b l e d . Of t h e 8 8 0 I n f e c t e d p e r s o n s , 4 6 4 ( 5 2 . 7 % ) w e r e a w a r e of the mode o f t r a n s m i s s i o n of t h e d i s e a s e . Very f e w of the I n f e c t e d persons d e p e n d e d o n W e s t e r n m e d i c i n e m a j o r i t y 788 ( 8 9 . 5 % ) d e p e n d e d on t r a d i t i o n a l m e d i c i n e . Of t h e 1 , 4 2 1 h o u s e h o l d s v / I s l t e d 1 , 3 5 7 ( 9 5 . 5 % ) n e v e r f i l t e r e d t h e i r d r l n k l n q w a t e r w h i l e none of t h em c a r e d t o b o l l the w a t e r b e f o r e d r l n k l n q . H o w e v e r , all h o u s e - h o l d s a g r e e d t h a t t h e y h a v e b e e n I n f o r m e d t o dc s o
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    INTERACTIONS OF QUININE AND SEROTONERGIC AGENTS IN PENTOBARBITONE - INDUCED SLEEP IN RATS
    (1994-04) MODUPE, BADEJOGBIN OLUYOMI
    The interactions between quinine serutuninergic agents on the EEG, EMG changes and behavioural sleep induced by pentobarbitone were studied in rats. All drugs were injected i ntr aper i tonealy. The sedative-hypnotic effect of pentobarbitone (5-30mg./kg) was found to be dependent on dose, with hypnosis being attained by the higher dose range (15-30mg/kg) . High dose (25mg/kg) of pentobarbitone synchronised the F C O C and BSRF of the control EEG in the slow wave sleep (SW3) stage with particular depression of the RF arid the EMG. When administered singly and in high doses (12-64mg/kg), 5- hydroxytryptophan (5-HTP) and quinine (5-50mg/kg) respectively showed sedative effects that were dose- dependent. High dose (20mg/kg) of Quinine sychronised the resting EEG and Initially briefly stimulated, though eventually predominantly depressed the EMG, suggesting a mechanism similar to that of the general CNS depressants. Low dose (0.1mg/kg) of quinine did not sedate but activated the entire resting state or control EEG and EMG. These were evident as faster, lower amplitude, asynchronous, mixed frequencies voltages and slightly increased multiple motor-unit voltages respectively. On sleep induced by pentobarbitone,5-Hydroxytryptophan 5-HTP (8-32mg/kg) and high doses (20-50mg/kg) of quinine respectively caused a potentiation that was marked by prolonged ix duration uT pentobarbitone-induced bleep. On the EEG and EMG patterns under pentobarbitone (25mg/kg), quinine 20mg/kg Increased the wave amplitude of the FC and OC with profound slowing of the BSRF and further reduction of muscle activity (muscle relaxation). Low doses (0.05 and 0.1 rug/kg) of quinine delayed the onset of sleep induced by pentobarbitone by 64% and 36% and shortened the duration respectively by 23% and 20%, the EEG arid EMG activities were also activited. A high dose (25mg/kg) of quinine potentiated 5-HTP-induced prolongation of pentobarbitone sleep by 23% while low dose (0.05mg/kg) of quinine decreased it by 40%. P-Chlorophenylalanine ((PCPA), 300mg/ky) reduced the duration of pentobarbitone sleep and antagonised the potentiation of pentobarbitone sleep by quinine. Ketanserin (2.5mg/kg) not only potentiated pentobarbitone sleep but enhanced significantly the potentiation of pentobarbitone sleep by 5-HTP (16mg/kg) as well as by quinine (25mg/kg). Methysergide (8mg/kg), an antagonist of both 5-HT1 , and 5- HT; receptors and a partial agonist of 5-HT, receptor partially antagonised the potentiating effect of high dose of quinine on pentobarbitone sleep. The present data show that depending on the dose, quinine has both excitatory and inhibitory effects on the state of condousness and that serotoninergic mechanism(s) may under the its effect on the state of sleep in rats.
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    A COMPARATIVE STUDY OF THE EFFECTS OF GONADECTOMY AND TAMOXIFEN TREATMENT ON ACID GASTRIC SECRETION IN ALBINO RATS
    (1995-03) ETTARH, REMAKE RENNER
    The effects of gonadectomy and tamoxifen administration on basal and histamine-stimulated gastric acid secretion in male and females rats were studied. The effects on body and stomach weights were also studied. Gonadectomy was performed 30 days prior to gastric acid secretion estimation, and tamoxifen was administered subcutaneously for 30 days before gastric acid secretion estimation. Gastric acid output was determined by the continuous perfusion methoi of Ghosh and Schild (1958). Both basal and histamine-stimu1ated gastric acid secretion in 14 castrated male rats were not significantly difference from those in 14 tamoxifen-treated nale rats (P > 0.001). Similarly, there was no significant difference between basal and histaminestimulated gastric acid secretion in 14 ovariectomized rats, and 14 tamoxifen-treated female rats (p > 0.001). Basal and histamine-Stimulated gastric Acid outputs were significantly reduced in tamoxifen-treated male rats ( P < 0.001), bolow the values obtained from 12 control male rats. This effect increased as the duration of treatment was increased. In female rats, basal and histamine-stimulated gastric acid secretion both Increased following tamoxifen administration, above the value for 12 control female rat3 (P < 0.001). This response also increased with increase in the duration of tamoxifen administration. Castrated male rat3 and tamoxifen-treated male rats both gained significantly less weight than control male rats (P<0.001). Ovariectomized rats gained significantly more weight than control female rats (P < 0.001). Tamoxifen-treated female rats gained no weight throughout the period of treatment. Stomach weights were not significantly different (P > 0.001) in either gonadectomized or tamoxifen-trsated male and female rats. The effect of tamoxifen on gastric acid secretion in male rats is likely due to its antiandrogenic effect, while the result observed in female rats may be due to its antagonism of oestrogen. The results suggest that the susceptibility of males and females to peptic ulceration is not greater following tamoxifen administration than it is after castration or ovariectomy.