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Initial characterizations of live-Salmonella-containing early (LSEP) and late phagosomes (LSLP) in macrophages show that both phagosomes retain Rab5 and EEA1. In addition, LSEP specifically contain transferrin receptor whereas LSLP possess relatively more rabaptin-5. In contrast to LSLP, late-Salmonella-containing vacuoles in epithelial cells show significantly reduced levels of Rab5 and EEA1. Subsequent results demonstrate that both phagosomes efficiently fuse with early endosomes (EE). In contrast to LSEP, fusion between LSLP and EE is insensitive to ATPγS treatment. Furthermore, LSLP fuses with EE in absence of NEM-sensitive fusion factor (NSF) as well as in the presence of NSF:D1EQ mutant demonstrating that LSLP fusion with EE is NSF independent.

A large number of oil wells in Kuwait were damaged and ignited by the retreating Iraqi troops during the 1991 Gulf War. The resulting spillage of huge volumes of crude oil on the surface gave rise to oil lakes and crude oil–impregnated soil. Moreover, products of crude oil combustion had spread over a large tract of the ground surface, causing widespread contamination of soil. Hydrocarbon contamination of ground water by the infiltrating runoff water carrying the contaminants from the surface soil to the water table and/or through direct contact with the crude oil leaking through the damaged casing in the subsurface was feared. This preliminary study was carried out to investigate the extent and nature of this possible contamination of ground water. The results indicate that the shallow fresh water lenses present under the Umm Al-Aish water field and in the southeastern parts of the Raudhatain water field in North Kuwait were affected by hydrocarbon pollution. Standard methods like the determination of the contents of the total petroleum hydrocarbon by the Fourier transform infrared method and 16 polyaromatic hydrocarbons using the gas chromatography-mass spectrometry method did not work well, possibly due to the environmental degradation of the crude oil over time. The fluorescence methods and the total organic carbon and total organic matter gave better indications of the intensity and the extent of ground water pollution. The brackish water fields of South and Central Kuwait were, however, free of any indications of hydrocarbon contamination.

Recent studies have shown that phagosome maturation depends on the balance between pro-inflammatory and anti-inflammatory cytokines, indicating that cytokine modulates phagosome maturation. However, the mechanism of cytokine-mediated modulation of intracellular trafficking remains to be elucidated. Here, we have shown that treatment of macrophages with IL-6 specifically induce the expression of Rab5 through the activation of extracellular signal-regulated kinase, whereas IL-12 exclusively upregulate the expression of Rab7 through the activation of p38 MAPK. We have cloned the 5′-flanking regions of the rab5c or rab7 into the promoterless reporter vector. Our results have shown that cells transfected with rab5c chimera are transactivated by IL-6, and IL-12 specifically transactivates cells containing rab7 chimera. Moreover, our results also show that IL-12 induces lysosomal transport, whereas IL-6 stimulates the fusion between early compartments in macrophages and accordingly modulates Salmonella trafficking and survival in macrophages. This is the first demonstration showing that cytokine differentially regulates endocytic trafficking by controlling the expression of appropriate Rab GTPase, and provides insight into the mechanism of cytokine-mediated regulation of intracellular trafficking.

A conjugate of the antineoplastic drug daunomycin (DNM) with maleylated bovine serum albumin (MBSA-DNM) was taken up with high efficiency by a multidrug resistant variant, JD100, of the murine-macrophage tumour cell line, J774A.1, through the scavenger receptors resulting in cessation of DNA synthesis. In contrast, free DNM at similar concentrations did not affect the incorporation of [3H]thymidine by these cells. These results suggest that receptor-mediated intracellular delivery of antineoplastic drugs could be a viable and new approach for overcoming the problem of multidrug resistance in chemotherapy of neoplastic diseases.

The transmissivity (T) distribution in the Dammam Formation aquifer within the State of Kuwait was investigated. It was found that up to 29% of the spatial variation in the log10 T values could be explained by a multiple linear relation with the coordinates of the observation site, whereby the log10 T showed a decreasing trend towards north and east. The deviations of the log10 T from the first degree trend were kriged using the semivariogram constructed on the basis of the available T data. The resulting values were added to the logio T values estimated from the linear relation with the coordinates, to derive the most likely values of log10 T at prespecified points. The technique provides estimates of transmissivity in areas away from the existing water fields. The T distribution with respect to the structure of the Dammam Formation was also investigated. The hypothesis that the transmissivity of the Dammam Formation was higher on the structural highs could not be substantiated, mostly because not enough data were available from such areas.

Injection of water and subsequent withdrawal were carried out in three existing water wells (SU-10, C-105, and SU-135A) in Kuwait. The objective of the study was to assess the technical feasibility of artificial recharge in the carbonate Dammam Formation and the clastic Kuwait Group aquifers. In the absence of any pretreatment of injection water and measures for maintenance of line pressure, clogging from suspended solids and air entrapment occurred in all three experiments. It was, however, possible to inject for one month in Wells SU-10 and C-105 where injection took place in the Dammam aquifer. In Well SU-135A, where the Kuwait Group aquifer was the target for injection, clogging became so severe that the injection experiment had to be abandoned. The injection/withdrawal data were analyzed with the help of a multi-aquifer flow model and a transport model. The models took into account the effects of crossflow within the boreholes on the distribution of intake and discharge rates for different aquifers, and hence, on the recovery efficiency. The experiments suggested that the artificial recharge of the Dammam and the Kuwait Group aquifers was technically feasible. The problem of clogging was, however, more severe for the Kuwait Group.

Kuwait is an arid country with no surface water and very limited resources of useable ground water. These ground-water reserves have been heavily exploited since the 1960s, which has led to substantial decline in the potentiometric surface of the aquifers. A regional numerical model, calibrated under both steady and unsteady-state conditions, has been used to investigate the hydrodynamic impacts of different ground-water management options on the potentiometry of the aquifers. The results indicate that there is a real danger of either dewatering the aquifers, or deteriorating water quality by upconing and sea-water intrusion, if the present trend of increasing withdrawal rates continues unchecked. In fact, the study suggests that even if the withdrawals are completely stopped in the near future, the aquifers will not be restored to their pre-1960 conditions by the year 2010. Artificial recharge of the aquifers will have, however, beneficial effects on the potentiometric surfaces and should be considered.

The residential areas of Kuwait City have been affected by a rise in the subsurface-water level in recent years, causing waterlogging and flooding of the basements of buildings. To study this phenomenon, and to ascertain its causes, a numerical aquifer simulation model was developed. The aquifer model showed that, over the period 1961-1985, the net yearly addition to the aquifer storage due to the contribution from man-made sources like sewage systems, irrigation, and water distribution networks, ranged from 8,300 to 10,100 m3 d−1, causing a subsurface-water-level rise of about 5 m locally, resulting in high water-table conditions. A maximum local rise in the water table of 2.5 m was predicted between the end of 1985 and 1990, if no remedial actions are undertaken. Preventive methods to reduce or eliminate recharge from man-made activities would help control the water-level rise and even lower the water table in affected areas. Remedial measures to lower and maintain the subsurface-water level at acceptable depths would entail the withdrawal of significant quantities of ground water.

A FORTRAN program was developed to obtain the transmissivity, storage coefficient, and leakage factor for a leaky confined aquifer from pumping test data. The automated method computes the aquifer parameters faster and without bias when compared with the manual curvematching methods commonly used. Aquifer parameters obtained from published pumping test data using the software compare closely with those estimated by manual curve-matching methods. The automated method cannot, however, detect the presence of recharge/discharge boundaries within the area of investigation or large deviations of data due to errors in data collection or data recording.

This paper presents a comparative study of inelastic interactions of proton-Emulsion, 12C-Emulsion and 24Mg-Emulsion at 4.5 GeV/c per nucleon. The multiplicity distribution and their correlations have been studied. A strong correlation between 〈ns〉 and nh in case of 24Mg-Emulsion and 12C-Emulsion is observed which is not so in the case of proton-Emulsion interaction. It is also observed that 〈ns〉 increases with the increase of the projectile mass. The angular distribution of the target fragments in 24Mg-Emulsion and 12C-Emulsion interactions show massive forward collimations. Comparison is also made in the pseudorapidity distributions of 24Mg-Emulsion, 12C-Emulsion and proton-Emulsion interactions. The result shows many interesting features. Eine vergleichende Studie der Proton-Emulsion-Schwerionen-Emulsionwechselwirkung bei 4,5 GeV/c pro Nucleon Die inelastischen Wechselwirkungen von Protonen, 12C- und 24Mg-Ionen mit Emulsionen werden verglichen. Dazu wird die Multiplizitatsverteilung und ihre Korrelationen untersucht. Es kann gezeigt werden, das die Zahl der Schauerpartikel im Falle der 12C-, 24Mg-Emulsionwechselwirkungen fest zur Zahl der hochionisierenden Partikel korreliert ist und mit der Projektilmasse wachst. Die Schwerionenexperimente zeigen eine vorwarts collimierte, raumliche Verteilung der Targetfragmente. Die Pscudorapiditatsverteilung wird in allen Experimenten untersucht.

Values of transmissivity and storage commonly are derived for a nonleaky confined aquifer by manual curve matching of pumping-test data. Automatic matching of pumping-test data with the Theis type curve is possible using the method of least squares, provided the Cooper-Jacob approximation of the well function W(u) is considered. A FORTRAN program was developed to carry out this automated matching. Results derived from published data show that the method gives parameters close to the ones derived by the standard method of manual curve matching.