Equine trypanosomosis in the Central River Division of The Gambia: a study of veterinary gate-clinic consultation records

The objective of this study was to provide epidemiological information of equine trypanosomosis in the Central River Division (CRD) of The Gambia. Therefore, 2285 consultations records of equines, admitted in a gate-clinic at Sololo in CRD, were studied retrospectively. The data were recorded in the period between September 1995 and July 2002 and comprised consultations of 2113 horses and 172 donkeys. 'Trypanosome infection' was the most frequently diagnosed condition and accounted for 61% of the cases. Horses were more frequently diagnosed with trypanosome infections than donkeys (p<0.001), with an occurrence of 63% compared to 43% in donkeys. In both horses and donkeys, trypanosome infections were mainly due to Trypanosoma congolense (64%) and T. vivax (32%). There was no difference observed in the occurrence of trypanosome infections in male or female donkeys (p=0.585), but there were more female (67.8%) horses observed with trypanosome infections than male horses (60.7%; p=0.003). There was no difference observed in the occurrence of trypanosome infections in donkeys older or younger than 1 year (p=0.130), but more older horses (63.2% >1 year) were observed with trypanosome infections than young horses (54.5% <1 year; p=0.033). The number of donkeys and horses with trypanosome infections decreased during the rainy season (June-September). The majority of equines that were admitted with trypanosome infections were severely anaemic. The average packed cell volume (PCV) declined with increasing parasitaemia (p=0.006). Seventy-four percent of the farmers' predictions of trypanosome infections in their equines were confirmed by darkground-microscopy. That proved that farmers had a fairly accurate knowledge of the diseases affecting their equines. The treatments executed at the gate-clinic were generally effective. The few (0.4%) relapses of the T. vivax infections that were previously treated with diminazene aceturate in this study were not sufficient to prove drug resistance. The study showed that the analysis of consultation records at a gate-clinic can provide complementary information to conventional epidemiological studies in the same research area.

Susceptibility of West African Dwarf goats and WAD×Saanen crosses to experimental infection with Trypanosoma congolense

West African Dwarf goats (WADs) and their Saanen crosses were experimentally infected with Trypanosoma congolense. No significant differences were found between trypanosome parasitaemia and antibody response of the crossbred and WAD goats. Neither the WAD goats nor the Saanen crosses were able to control the drop in PCV following trypanosome infection. The level of anaemia caused by the trypanosome infection was similar in the two breeds during the trial. Based on these findings, no difference in tolerance or susceptibility to T. congolense could be demonstrated between the WAD goats and their Saanen crosses. Although the weight of all goats increased during the trial, the crosses gained significantly more weight than the WAD goats. The trypanosome infection reduced the growth rate of both breeds, but this reduction was not statistically significant. Crossbreeding trypanotolerant WADs with trypanosusceptible Saanen goats might, therefore, be an effective means of increasing productivity.

Cord blood banking: volume reduction using "Procord" Terumo filter

Cryopreserved cord blood (CB) banking, space storage, and ABO major incompatibility transfusion as well as potential progenitor cell loss during processing, are the subjects of this study. We evaluate processing of fresh and thawed CB on "Procord" (Terumo Corp., Japan). On 16 freshed CBs, mean NC, CD34, CFU-GM yields were, respectively, 54% (SD +/- 20), 75% (SD +/- 25), and 171% (SD +/- 168) in a final volume of 20 ml. Final product was enriched in mononuclear cells (mean 69% granulocytes depletion) with reproducible erythrocyte and platelet depletions means of 97% (SD +/- 1.5) and 93% (SD +/- 8). On seven previous whole frozen CB units, Procord gave comparable red blood cell (98%) depletion with 53% (SD +/- 30) mean CD34 recovery. Procord is an efficient method for erythrocyte depletion of CB, and recoveries of NC and progenitor cells are comparable to those obtained with similar processing. Nevertheless, as all existing methods, it is associated with cell and progenitor cell loss.

Health and productivity of traditionally managed Djallonke sheep and West African dwarf goats under high and moderate trypanosomosis risk

Trypanosome infections, packed red cell volume levels (PCV), body weight and nematode faecal egg counts of village-based small ruminants were monitored in two areas in The Gambia with either moderate or high trypanosomosis risk for 24 and 30 months respectively. Outflows from the flock and new-born animals were recorded and data on housing and management were compiled. Reported mortality rates were higher in goats than in sheep, but for both species highest in the moderate risk area. The peak of trypanosome infections lagged the peak of tsetse densities by 1-3 months in both areas. Trypanosoma vivax was the predominant species found in the infected animals, followed by T. congolense. Trypanosome prevalence was, in general, higher in sheep than in goats but only significantly higher during Year 1 in the moderate risk area. Trypanosome infection reduced the PCV level significantly and seasonal effects indicated significantly lower PCV levels during the rains. Trypanosome infection significantly depressed weight gain in both species at periods where infection rates were highest. In both species considerably lower weight gains were observed during the rainy season. Abortion rates were higher in goats than in sheep in both study sites, and highest in the high-risk site. Trypanosome infection in ewes in the high risk area increased lamb mortality significantly but had no effect on birth weights, nor on growth rates up to 4 months. Offspring mortality up to 4 months was generally high at both sites. Trypanosome infection in the dam between 3.5 to 7 months post parturition significantly increased parturition interval in both species. Peak faecal egg output occurred at the end of the rainy season and was highest for both species in the moderate risk site. Poor grazing management was found responsible for a seasonal nutritional constraint. Based on these results, these breeds of sheep and goats can be considered as trypanotolerant since they are able to remain productive under high and moderate levels of trypanosome challenge. Nevertheless, trypanosomosis affected their health and production level as shown by reduced PCV levels, depressed weight gains, longer parturition intervals and higher lamb mortality. In addition, during the rains, helminth infections and poor management leading to nutritional constraints had also a negative impact on health and production and therefore influenced the innate resilience to trypanosomosis in those indigenous breeds. Adaptations in management may have an equal impact as certain disease control measures to improve biological and economical returns from small ruminants in tsetse infested rural areas.

Effects of Trypanosoma congolense infection and diet on puberty, age at first lambing and haematology changes in Djallonké ewe lambs

The interactions between T. congolense infection and nutritional supplements on onset of puberty and age at first lambing were observed in 24 young Djallonké ewes. As experimental design, a randomised complete block design was used with four treatment combinations, of which two were kept on a restricted diet (L), the remainder on an unrestricted diet (H) and half of each nutritional group being infected with T. congolense (LI and HI), the remainder serving as controls (LC and HC). Infection with T. congolense took place at an average age of 6 months and 15 days. Mortality due to trypanosome infection was zero and clinical symptoms were not obvious. Intensity of parasitaemia and packed cell volume (PCV) drop following trypanosome infection were similar in both infected groups (HI and LI). High dietary supplementation resulted temporarily in a better haematopoietic response following trypanosome infection, measured as a macrocytic anaemia. Dry matter intake (DMI) was significantly depressed in the HI group immediately following infection. Trypanosome infection had a negative effect on live weight gain during the chronic phase, with the difference being most obvious in the HI group (interaction diet x infection; p< or =0.05). Whereas trypanosome infection had no significant effect, high supplementary feeding significantly reduced the age at first cycling. Age at first lambing was similarly reduced by the diet. Trypanosome infection tended (p< or =0.09) to delay age at first lambing with a mean difference of 31.5+/-22.4 days between infected and controls. Interactions between diet and infection for age at first cycling/lambing were not significant, indicating these effects were just additive. Neither birth weights nor growth rates of offspring born to the experimental animals were significantly affected by previous trypanosome infection, nor by the diet of the dam. In contrast, lamb mortality up to 3 months of age was significantly increased by infection of the dam and most losses arose in group LI. In conclusion, the effects of trypanosome infection on puberty and age at first lambing were indirectly mediated through depression of growth rates. Nutritional supplementation enabled a better erythropoietic response to T. congolense infection and better offspring survival rates but resulted in more depressed weight gains. The results however clearly indicated the delaying effect of insufficient feeding on onset of puberty and reproductive performance in young Djallonké sheep.

Haematological changes and antibody response in trypanotolerant sheep and goats following experimental Trypanosoma congolense infection

Ten West African Dwarf (WAD) female goats and twelve Djallonké ewes were artificially infected with a West African strain of Trypanosoma congolense and monitored during 36 weeks over an acute phase (weeks 0-12) and chronic phase (weeks 13-36) to evaluate their haematological and immunological response. Parasitaemia, packed cell volume, red blood cells, haemoglobin, white blood cells and trypanosomal antibodies were assessed. Mean corpuscular volume and mean corpuscular haemoglobin concentration were calculated. The infected animals showed a persistent parasitaemia together with a chronic anaemia and significantly lower packed cell volume, red blood cell count and haemoglobin. The infected sheep developed a macrocytic, hypochromic anaemia during the acute phase changing to normocytic, hypochromic during the chronic phase, whereas, the infected goats developed a normocytic, normochromic anaemia during the acute phase and normocytic, hypochromic during the chronic phase. A significant increase in WBC counts was observed only in the infected sheep during the chronic phase. Trypanosomal antibody titres were significantly higher in the infected sheep than in the infected goats. Both species are regarded as trypanotolerant but Djallonké sheep mount a better haematopoietic and immunological response to infection with T. congolense than WAD goats.

Oxygen carrying capacity and oxygen supply rate of artificial oxygen carrier, Neo Red Cell (NRC)

Neo Red Cell (NRC), which is the liposome encapsulated hemolysate, has been developed as an artificial oxygen carrier. Oxygen carrying capacity and oxygen supply rate of NRC were estimated by continuous measurement of dissolved oxygen concentration in a spinner vessel. Oxygen carrying capacity of the medium was risen by adding NRC. The oxygen supply rate of the NRC medium containing hepatocytes was determined by the oxygen consumption rate of hepatocytes. The addition of NRC gave no effect on the oxygen transfer rate from gas phase to liquid phase (or kL a value) of the solution in the spinner vessel. The rate of oxygen absorption to NRC was limited by the oxygen transfer rate from gas phase to liquid phase in the spinner vessel. These results indicate that the oxygen supply from NRC may sustain the high-density culture of mammalian cells.

Cationic uncouplers of oxidative phosphorylation are inducers of mitochondrial permeability transition

To determine whether cationic uncouplers of oxidative phosphorylation induce permeability transition in mitochondria, the effects of the divalent cationic sulfhydryl cross-linker copper-o-phenanthroline (Cu(OP)2) and the cyanine dye tri-S-C4(5) on rat liver mitochondria were examined. Like Ca2+, they accelerated mitochondrial respiration with succinate and induced mitochondrial swelling when inorganic phosphate (Pi) was present in the incubation medium. The acceleration of respiration and swelling were inhibited by the SH-reagent N-ethylmaleimide, and by the specific permeability transition inhibitor cyclosporin A (CsA). In addition, these cations, like Ca2+, induced release of ADP entrapped in the mitochondrial matrix space, and the morphological change of mitochondria induced by these cations was essentially the same as that induced by Ca2+. It is concluded that the uncoupling actions of Cu(OP)2 and tri-S-C4(5) are due to induction of permeability transition in the inner mitochondrial membrane.

Effects of Trypanosoma congolense and nutritional supplements on establishment and outcome of pregnancy in trypanotolerant Djallonké ewes

Interactions between Trypanosoma congolense and nutritional statue were studied in 42 ewes, bred at the peak of parasitaemia after synchronisation of oestrus. As experimental design a randomised block design was used with four treatment combinations (2 x 2 factors), of which two were on restricted diet (L), the remainder on an unrestricted diet (H) and half of each nutritional group infected with T. congolense (LI, HI) remainder serving as controls (LC, HC). Severity of parasitaemia was not influenced by supplementation and mortality rates were higher in the HI and LC groups, but these differences were found not significant. Progesterone levels during the synchronised cycle were significantly lower in the infected groups. Levels of pregnant specific protein B (PSPB) in pregnant sheep at days 21 and 26 and were not significantly affected by nutrition or infection, despite the tendency of a decrease in infected groups. T. congolense clearly affected establishment of pregnancy, as shown by lower rates of pregnancy and extended intervals between breeding and confirmation of pregnancy, nor was there any benefit of nutritional supplementation. Mean progesterone concentration during pregnancy, in those ewes which lambed, was not different between groups. The effect of the T. congolense infection on the outcome of pregnancy was not clear with the LI and HC performing well and poor pregnancy outcomes on groups HI and LC, although differences in litter size might explain these anomalies. It is concluded that the most pronounced effect of T. congolense was a negative influence on establishment of pregnancy, with nutritional supplementation unable to overcome this effect but having a beneficial influence on maintenance and successful outcome of pregnancy. However, individual exceptions indicate that some ewes cope better with the negative effects of infection and poor nutrition.

Abattoir survey of sheep and goats in The Gambia

An abattoir survey of sheep and goats was carried out in The Gambia for one year. A total of 1248 goats and 438 sheep, predominantly young females, were slaughtered and sampled. Sixty per cent of the females of both species were pregnant. There were no significant differences between the dressing percentages of different breeds and age groups. Sex and stage of pregnancy had a significant influence on carcase yields in both species. In goats the highest carcase yields were obtained during the early dry season. Most of the animals were clinically healthy and there were few pathological findings postmortem. In both species, there was a seasonal fluctuation of packed cell volume (PCV), with a minimum during the rains, and although the prevalence of trypanosomiasis was low it reduced the PCV. Faecal egg counts of Trichostrongylidae were highest during the rainy season and goats had higher faecal egg and coccidial oocyst counts than sheep. In sheep, a breed difference was observed for PCV and an age difference for egg excretion. The peak or higher rates of egg excretion occurred during the rains in both species. The immune status against peste des petits ruminants was significantly lower in goats (39 per cent) than in sheep (49.5 per cent). Antibodies against bluetongue virus were found in 62.6 per cent of goats and 55.8 per cent of sheep.

The interaction of Trypanosoma congolense and Haemonchus contortus in Djallonké sheep

The interaction between Trypanosoma congolense and Haemonchus contortus was studied in 5 groups of 8 Djallonké sheep. Two groups received a single infection with either H. contortus or T. congolense, and 2 groups were infected with T. congolense followed by H. contortus (TH) or vice versa (HT). One group was kept as uninfected controls. Mortality due to infection was observed only in the dual infection groups. In the TH group, the effects were more acute whereas in the HT group they were more chronic. No significant differences in weight gain could be demonstrated between infected and control groups. Djallonké sheep are able to withstand a single infection with either T. congolense or H. contortus, which confirms their trypanotolerant nature and provides preliminary indication of resistance against helminth infections. However, when exposed to successive infections with both parasites, some of the animals lose this tolerance.

Long-term effects of an experimental infection with Trypanosoma congolense on reproductive performance of trypanotolerant Djallonké ewes and west African dwarf does

Ten West African Dwarf (WAD) does and 12 Djallonké ewes were artificially infected with a West African strain of Trypanosoma congolense and observed over two years. The infected animals showed a chronic anaemia together with a persistent parasitaemia but very low mortality and increase in body weights was not significantly different from the control. In the infected sheep significant differences were found in offspring production at three and five months due to a higher mortality among the lambs. The infected goats had more abortions and stillbirths and period to first kidding, total number of parturitions, production at birth, one, three and five months were significantly different from the controls. A productivity index was calculated and revealed that a chronic T congolense infection significantly decreases the productivity of WAD goats during two years whereas in Djallonké sheep, the loss in productivity is recovered after one year. Although both species are regarded as trypanotolerant, the Djallonké sheep show a better tolerance to a chronic T congolense infection that the WAD goats.

Cytoplasmic calcium levels and membrane fluidity of platelets in contact with polyether-polyamide multiblock-copolymer surfaces

Cytoplasmic calcium levels and the membrane fluidity of rabbit platelets stored in mini blood bags of crystalline-amorphous microstructured polymers (polyether-polyamide multiblock-copolymers) were studied. Fluorescent dye (Fura 2 or 1,6-diphenyl-1,3,5-hexatriene)-loaded platelet suspensions were stored at 37 degrees C for 1 h in the blood bags, and metabolic changes in the platelets during storage were evaluated by the fluorescent spectroscopic technique. The surfaces of poly(vinyl chloride) and polyolefin elastomers, which are used for commercially available blood bags, enhanced the progress of platelet metabolism; i.e., there was a dramatic decrease in membrane fluidity and an increase in [Ca2+]i. Furthermore, the decrease in membrane fluidity was observed prior to the increase in [Ca2+]i. These results suggest that the decrease in membrane fluidity of platelets in contact with polymer surfaces can be the dominant stage in the activation of these platelets. In contrast, the surfaces of polyether-polyamide multiblock-copolymers exhibited few changes in either membrane fluidity or [Ca2+]i levels. These results suggest that the platelets in contact with the crystalline-amorphous microstructured copolymer surfaces can be inert and inactivated in terms of the prevention of a decrease in membrane fluidity.

Susceptibility to different tick genera in Gambian N'Dama and Gobra zebu cattle exposed to naturally occurring tick infestations

Tick collection on one side of the body and whole tail was performed weekly over one year on 11 Gambian N'Dama (Bos taurus) and 11 Gobra zebu (Bos indicus) cattle to assess breed susceptibility to naturally occurring ticks. Enzyme-linked immunosorbant assay was also performed to assess the serological prevalence of Anaplasma marginale antigen and Babesia bigemina antibody. Packed red cell volume was measured and liveweight gain was recorded. Significantly higher numbers of Amblyomma variegatum (P < 0.002) and Hyalomma spp. (P < 0.001) were found on Gobra zebu than on N'Dama cattle. The serological prevalence of A. marginale antigen was significantly (P < 0.001) lower in N'Dama breed, whilst no difference in the serological prevalence of B. bigemina antibody was found between N'Dama and Gobra cattle. Packed red cell volume was negatively affected by A. marginale infection in both breeds, but to a lesser extent in N'Dama cattle. Liveweight gain was significantly (P < 0.003) higher in N'Dama in comparison with Gobra cattle during the period of abundance of A. variegatum and Hyalomma spp. adults. The significantly lower burdens of A. variegatum and Hyalomma spp. ticks in Gambian N'Dama in comparison with Gobra zebu cattle confirms previous findings. It also shows a more deleterious effect of ticks and tick-borne diseases on animal production and health in Gobra zebu than in N'Dama cattle. The presence of a tick resistant trait in N'Dama cattle is suggested.

A comparison of the susceptibility of Djallonké sheep and West African Dwarf goats to experimental infection with two different strains of Trypanosoma congolense

Two cloned strains of Trypanosoma congolense, of West and East African origin, were used to infect by intradermal inoculation two groups of young adult female Djallonké sheep and West African Dwarf goats. For a 3 month period post-infection, packed red cell volume (PCV), parasitaemia, body weight and clinical parameters were followed to evaluate their trypanotolerant nature and to control the pathogenicity of the two strains of T. congolense. Although the West African strain of T. congolense was more pathogenic than the East African strain, it seemed that the Djallonké sheep and the West African Dwarf goats, despite high levels of parasitaemia and a concomitant drop in PCV, showed a high degree of trypanotolerance, as reflected by zero mortality and an increase in body weight during 12 weeks of observation.

A comparison of field tick infestation on N'Dama, Zebu and N'Dama x Zebu crossbred cattle

Tick burdens, estimated from cumulative tick counts, were determined on N'Dama, Zebu and F1 N'Dama x Zebu crossbred cattle. N'Dama showed significantly fewer ticks than the Zebu and F1 cattle (P < 0.001). A previous trypanosomosis infection did not affect tick burdens on the three genotypes. Amblyomma variegatum had a prevalence of 84.8% and Hyalomma spp. 15.2%, with the ratio similar on all cattle breeds. Trypanosomosis infection increased the serological prevalence of Anaplasma marginale in Zebu and F1 cattle but not in N'Dama cattle. These observations supported the view that N'Dama cattle are less susceptible to tick attachment than Zebu cattle.

Plasma-depleted platelet concentrates prepared with a new washing solution

In certain clinical situations, complete removal of the plasma proteins from the platelet concentrates (PCs) is necessary by washing prior to transfusion. A simple electrolyte solution with a pH of 6.5 was developed for washing PCs. The platelet-rich plasma collected with acid-citrate-dextrose solution by apheresis in a 0.6-liter polyolefin bag was centrifuged. After removal of the supernatant plasma from pelleted platelet buttons, 200 ml of a washing solution consisting of 90 mM NaCl, 5 mM KCl, 3 mM MgCl2, 17 mM NaH2PO4, 8 mM Na2HPO4, 23 mM Na acetate, 17 mM Na3 citrate, 23.5 mM glucose, 2 mM adenine, 0.1% dextran, and 28.8 mM maltose (pH 6.5) was added to the pelleted platelet button. Steam sterilization of the solution was carried out under nitrogen to avoid caramelization of glucose. After resuspension of the pelleted platelet button with a washing solution and a second centrifugation, Seto additive solution (Seto sol, pH 7.4) was introduced into the bag to resuspend the platelet buttons for storage for 3 days at 22 degrees C. All of these procedures were completed within 3 h using a sterile docking device. In washed PCs, 99.1% of the plasma was removed and platelet recovery was 96%. The washed PCs were compared for 3 days with plasma-poor PCs consisting of 11% plasma and 89% Seto solution. There were no significant differences in percent hypotonic shock response, aggregation, energy metabolism, and morphology of platelets between the two groups during 3 days, except for significant swelling of 3-day-old platelets in washed PCs.(ABSTRACT TRUNCATED AT 250 WORDS)

A comparative study of gastrointestinal nematode egg output in N'Dama, Zebu and N'Dama x Zebu crossbred cattle

Strongyle faecal egg output was estimated in N'Dama, Zebu and N'Dama x Zebu crossbred (F1) cattle. N'Dama cattle showed a significantly lower prevalence of strongyle infection, as measured by faecal egg output, than F1 (P < 0.01) and Zebu (P < 0.001) cattle. In strongyle-infected animals, mean egg output was also significantly lower in N'Damas (P < 0.03) than in Zebus. A previous trypanosomiasis infection did not affect the results. The presence of a natural resistance trait to strongyle infection in N'Dama cattle is postulated.

Are free radicals involved in Ca(2+)-induced membrane damage of mitochondria?

Ca(2+)-Induced membrane damage of energized mitochondria has been proposed to be due to lipid peroxidation induced by Ca2+. To examine this possibility, we studied the effects of the radical scavenger, 3,5-di-tert-butyl-4-hydroxytoluene (BHT), and its derivative, 3,5-di-tert-butyl-4-methoxytoluene (MeO-BHT), on membrane damage of respiring mitochondria induced by Ca2+ in the presence of inorganic phosphate. Both compounds inhibited Ca(2+)-induced damage almost completely at 20 microM, and their effects were identical, although MeO-BHT had no radical scavenging ability. These results indicate that the protective effects of BHT and MeO-BHT are not due to their radical scavenging ability. Thus, free radicals are concluded not to be involved in Ca(2+)-induced membrane damage of mitochondria.

Comparative studies on N'Dama and zebu cattle following repeated infections with Trypanosoma congolense

Twenty N'Dama and eight zebu cattle were inoculated intradermally with bloodstream forms of a cloned strain of Trypanosoma congolense originating from East Africa. All inoculated cattle became parasitaemic. Zebus showed consistently higher levels of parasitaemia and lower packed red cell volume (PCV) percentages than did N'Damas. Three of the eight zebus required treatment when high numbers of trypanosomes were present in the blood and PCV values dropped below 15 per cent. None of the N'Dama cattle needed treatment. Statistical analysis was performed on the data to assess the variability of parasitaemia and PCV levels before and during infection of the N'Dama cattle. The variation in PCV values was large between individuals during the early stages of the disease and diminished as infection continued. After trypanocidal drug treatment and a recovery period of 14 months, the same animals were inoculated intradermally with T congolense bloodstream forms isolated and cloned in The Gambia. Differences in susceptibility to the ensuing disease were apparent when comparing N'Dama and zebu cattle. Five zebu cattle needed trypanocidal drug treatment, while none of the N'Damas needed drug intervention. Ranking the 20 infected N'Damas according to average PCV levels revealed that the animals responded similarly to both infections.

First autoclave-sterilized platelet-additive solution containing glucose with a physiological pH for the preparation of plasma-poor platelet concentrates

The glucose-free platelet-additive solution (termed AR solution), developed by Adams and Rock [Transfusion 1988;28:217-220], was modified by adding glucose as an energy substrate for platelets and maltose to prevent platelet lysis and by replacing sodium gluconate with sodium phosphate for better pH maintenance. The new platelet-additive solution (termed Seto solution) contained 90 mM NaCl, 5 mM KCl, 3 mM MgCl2, 17 mM tri-sodium citrate, 4.9 mM NaH2PO4, 20.1 mM Na2HPO4, 23 mM sodium acetate, 28.8 mM maltose, and 23.5 mM glucose with a pH of 7.4. The solution was sterilized by autoclaving in plastic bags in nitrogen to prevent glucose caramelization at high pH. Plasma-poor platelet concentrates prepared by adding Seto solution to the pelleted platelet buttons were stored in a LE-2 polyolefin bag at 22 degrees C with constant agitation for 5 days. The platelets suspended in Seto solution maintained oxygen consumption at a rate of 1.1 nmol/min/10(9) platelets after 5-day storage, with glucose consumption and lactate production rates of 0.5 +/- 0.2 and 1.2 +/- 0.2 nmol/min/10(9) platelets, respectively. This resulted in a final mean pH of 7.0. Those suspended in AR solution ceased glycolysis within 3 days because residual plasma glucose had been consumed. This was associated with decreases in percent hypotonic shock response and aggregation induced by adenosine diphosphate and collagen. Lactate dehydrogenase discharge in AR solution was 5 and 8 times higher at day 3 and day 5, respectively, than that of Seto solution. Morphologically, there were no ballooned platelets after storage in Seto solution.(ABSTRACT TRUNCATED AT 250 WORDS)

Comparison of sesame cake and cottonseed as supplementary sources of protein to weaned N'Dama bull calves in The Gambia

The potential for increased productivity of N'Dama cattle in response to small supplementary inputs of proteinaceous by-products has been shown to be substantial under village husbandry conditions in The Gambia. Young N'Dama bulls were used to compare sesame cake with cottonseed as sources of supplementary protein during the wet and early dry seasons of 1987. They were fed 0, 40, 80 or 160 g crude protein/day in these forms for four months. Supplementation significantly increased growth rate from 169 g/d in controls to means of 272 and 271 g/d for those given sesame cake and cottonseed respectively; there were no significant differences among the supplemented groups. During the four months of the dry season immediately after supplementation ceased all previously supplemented groups grew significantly more rapidly than the controls (at least P less than 0.05), indicating a substantial carry over effect of the supplements. Over this period the mean gain of the groups previously given sesame cake exceeded that of those that had received cottonseed (217 cf. 158 g/d; P less than 0.01). The economic benefits of these responses were substantial.

Protective effect of the plasticizer di(2-ethylhexyl) phthalate against damage of the mitochondrial membrane induced by calcium: possible participation of the adenine nucleotide translocator

The effect of di(2-ethylhexyl) phthalate (DEHP) on the response of isolated rat liver mitochondria to Ca2+ was investigated. DEHP was found to inhibit more than 60% of the auto-accelerating release of respiration induced by 100 microM Ca2+, being maximally inhibitory at 40 microM. Prior addition of DEHP also partially inhibited Ca2+-induced swelling of the mitochondrial matrix. However, DEHP did not change the net rate of Ca2+ uptake measured by the steady-state infusion method. DEHP also reduced the rate of adenine nucleotide exchange across the mitochondrial membrane. Another alkyl phthalate and alkyl citrates had similar effects on Ca2+-induced membrane damage, but their potencies depended on the lengths of their alkyl chains. These results suggest that the effects of DEHP and other alkyl esters on mitochondrial functions are mainly based on their actions on membrane lipids surrounding adenine nucleotide translocator (AdNT), resulting in alteration of the interaction between these phospholipids and AdNT, and consequent modification of the state of the protein.

A new polyvinylchloride blood bag plasticized with less-leachable phthalate ester analogue, di-n-decyl phthalate, for storage of platelets

To compare changes in platelets stored in the new di-n-decyl phthalate (DnDP)-plasticized polyvinyl chloride (PVC) bag with those in a di-(2-ethylhexyl) phthalate (DEHP)-plasticized PVC bag, single-donor apheresis platelet concentrates (PCs), 133 +/- 11 x 10(7) platelets per ml (n = 7), were stored with 94 +/- 3 ml of plasma in a new 1-liter bag with a surface area of 44 +/- 7.1 cm2 per 10(10) platelets. Oxygen and carbon dioxide gas diffusion properties of PVC-DnDP films were respectively, 1.6 and 2 times those of standard PVC-DEHP films. The amounts of DnDP leaked into the plasma of PCs were low at 0.58 +/- 0.06 mg per bag after 5-day storage, which is about one-eightieth the amount of DEHP leaked. The pH of PCs in PVC-DnDP bags amounted to 6.99 +/- 0.03 after 5-day storage, with glycolysis accelerated somewhat in the new bags. However, the platelet oxygen consumption was no different from that in the PVC-DEHP bags. Platelet aggregation and responses to hypotonic shock were significantly better in the new bags at the end of storage. Shape changes of platelets into spherical forms with dendrites were more frequently observed in PVC-DnDP bags than in PVC-DEHP bags. The study indicated that platelets stored in the new DnDP-plasticized PVC bags have retained aggregation and responses to hypotonic shock more than platelets in the PVC-DEHP bags, but spherical forms and anaerobic metabolism increased in the new bags.

Effect of the plasticizer di-(2-ethylhexyl)phthalate on oxidative phosphorylation in rat liver mitochondria: modification of the function of the adenine nucleotide translocator

The effect of di-(2-ethylhexyl)phthalate (DEHP) on oxidative phosphorylation of isolated rat liver mitochondria was investigated. DEHP at concentrations of 20-1000 microM had no effect on state 4 respiration, but at 40 microM, DEHP decreased the rate of state 3 respiration by about 20%. Although DEHP had no effect on electron transport through the respiratory chain, it decreased the rate of adenosine triphosphate (ATP) synthesis. Its inhibition of ATP synthesis showed a similar concentration dependence to that of state 3 respiration. Furthermore, DEHP at 40 microM inhibited the uptake of [3H]adenosine diphosphate into mitochondria. DEHP also retarded the action of cationic uncoupling agents, which are known to modify the 29000-dalton protein involved in adenine nucleotide exchange. These results suggest that DEHP affects the activity of adenine nucleotide exchange and consequently partially decreases the rate of state 3 respiration. The action of DEHP on the 29000-dalton protein involves a protective effect against mitochondrial damage induced by hydrophobic cations or heavy metal cations.

Management of a perforated endotracheal tube during orthognathic surgery

Oral and maxillofacial procedures require nasotracheal intubation that often obscures the anesthesiologist's direct vision of the surgical field. Premature extubation of a damaged endotracheal tube frequently requires replacement and poses a potential risk to the patient. This case illustrates a technique for replacing a damaged endotracheal tube using a nasogastric tube inserted within the damaged tube to suction secretions, insufflate oxygen, and serve as a guide for placement of a new endotracheal tube.

Incidence of pregnancy, changes in menstrual pattern, and recovery of endometrial function after discontinuation of medroxyprogesterone acetate therapy

The incidence of pregnancy, recovery of endometrial function, and changes in menstrual pattern were studied in 62 women who had received two or more intramuscular injections (150 mg) of medroxyprogesterone acetate (Depo-Provera) every three months and oral diethylstilbestrol (1 mg) daily for seven days every month. Immediately after discontinuing this therapy, 71% of the patients had regular menstrual cycles, 10% had irregular cycles, and 19% had amenorrhea. All the patients had regular cycles by the end of one year except one women who was probably menopausal. The average time required to conceive after stopping therapy was 9.3 months, range, 3 to 21 months). Conception was definitely delayed as shown by endometrial biopsies and the incidence of pregnancy. Within six months, 25% of the patients conceived and within one year, 69% conceived. By two years, four had not conceived. The percentage of pregnancies seemed to decrease with increased patient age.