Combined impacts of future land-use and climate stressors on water resources and quality in groundwater and surface waterbodies of the upper Thames river basin, UK.

It is widely acknowledged that waterbodies are becoming increasingly affected by a wide range of drivers of change arising from human activity. To illustrate how this can be quantified a linked modelling approach was applied in the Thames river basin in southern UK. Changes to river flows, water temperature, river and reservoir quality were predicted under three contrasting future "storylines"; one an extension of present day rates of economic development, the others representing more extreme and less sustainable visions. Modelling revealed that lower baseflow conditions will arise under all storylines. For the less extreme storyline river water quality is likely to deteriorate but reservoir quality will improve slightly. The two more extreme futures could not be supported by current management strategies to meet water demand. To satisfy these scenarios, transfer of river water from outside the Thames river basin would be necessary. Consequently, some improvement over present day water quality in the river may be seen, and for most indicators conditions would be better than in the less extreme storyline. However, because phosphorus concentrations will rise, the invoked changes in water demand management would not be of a form suitable to prevent a marked deterioration in reservoir water quality.

Predictive value of assessment of different modalities in the diagnosis of infantile cholestasis.

This study investigated the relative accuracy and roles of abdominal ultrasonography, hepatobiliary scintigraphy and liver biopsy in the diagnosis of infantile cholestasis. A total of 50 infants (27 females) aged 1 - 12 months were classified into those with intrahepatic causes of cholestasis (n = 22) and those with extrahepatic causes (n = 28). Cholestasis is caused by a wide range of conditions and diagnosis requires meticulous history taking, thorough clinical examination and many laboratory tests. The most common cause of intrahepatic cholestasis was found to be idiopathic neonatal hepatitis (54.5%), followed by infectious hepatitis (9.1%), metabolic liver diseases (9.1%), intrahepatic biliary atresia (9.1%) and Alagille syndrome (4.5%). The most common cause of extrahepatic cholestasis was extrahepatic biliary atresia (96.4%). The incidence of choledochal cyst was low (3.6%). The cornerstone of the diagnosis of infantile cholestasis was found to be liver biopsy, which was associated with a high degree of accuracy.

Detection of circulating schistosome antigens in serum and urine of schistosomiasis patients and assessment of cure by a monoclonal antibody.

From a panel of monoclonal antibodies (MAb), an IgM monoclonal antibody (7F1/6B) reactive with repetitive epitopes on S. mansoni soluble egg antigen was selected. This MAb was employed both as antigen capture and detection antibody in a sandwich ELISA and had a detection limit < 1 ng S. mansoni SEA/mi. Serum and urine samples were collected from rural students who had S. mansoni (169 subjects) or mixed S. mansoni and S. haematobium (64 subjects) infections. Samples were collected before and at 4, 8 and 12 weeks after praziquantel therapy. Circulating schistosome antigens (CSA) were demonstrated in 90% of sera and 97% of urine samples of S. mansoni group and in 91% of sera and 100% of urine samples of mixed infection group. All sera from 29 uninfected individuals, 30 patients with other parasites and 70% of 55 S. haematobium-infected subjects were negative in this assay. CSA level in serum and urine samples correlated positively with the number of S. mansoni eggs/g stool in both groups. A significant reduction in CSA level was observed in serum and urine samples after praziquantel therapy. By 12 weeks post-treatment, negativity was 98% in sera and 97% in urine of S. mansoni-infected group and 98% in sera and 91% in urine of mixed infection group. The data demonstrate that the use of MAb 7F1/6B for the detection of CSA provides a sensitive method for immunodiagnosis of schistosomiasis and monitoring of cure.

Assessment of cure in schistosomiasis patients after chemotherapy with praziquantel by quantitation of circulating anodic antigen (CAA) in urine.

The kinetics of circulating anodic antigen (CAA) levels in urine were studied in Egyptian male patients infected with Schistosoma mansoni or with both S. mansoni and S. haematobium, before treatment, and at one, three and six weeks after chemotherapy. A quantitative enzyme-linked immunosorbent assay (ELISA) demonstrated CAA in 82% of the serum and 89% of the urine samples from these 28 patients. To evaluate the possibility of circadian variability in urine CAA levels, samples were examined in 15 patients at four intervals during a 24-hour period. No significant differences in CAA titers were observed. Seventeen patients were subsequently treated with praziquantel and followed for six weeks. CAA titers in serum and urine decreased significantly one week after therapy. Thereafter, the profile of CAA titer in urine continued to show a parallel but delayed decline compared to that in serum. While all serum CAA titers became negative three to six weeks after treatment, urine titers were negative in 47% at three weeks and 69% at six weeks. The remaining positive patients had low titers. A significant quantitative correlation in CAA titer was found between serum and urine before and after treatment. Seventeen Egyptian control subjects with no active schistosome infection were negative for CAA in both serum and urine. Our results confirm that the CAA urine assay could be used as a sensitive and non-invasive method to diagnose the disease, and indicate that the assay can be used to monitor efficacy of schistosome chemotherapy.