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Hydrogeologist EurGeol Jose Martins Carvalho (BSc, PhD, DSc) gave his last lecture at the School of Engineering of Polytechnic of Porto in January 2014, bringing to a formal close an outstanding career in multidisciplinary hydrogeology teaching and practice (in Europe, Africa, Middle-East, Asia, South America) and in applied research. Nowadays, he is Emeritus Professor of the Polytechnic of Porto and Consultant Hydrogeologist. He has had a career spanning 50 years in military hydrogeology, exploration hydrogeology, environmental hydrogeology, groundwater engineering, hydrogeotechnics, urban water supply, water resources management and geothermics. This brief note aims to present the key milestones in his multifaceted professional career, acting as a geologist, a professor and a researcher of groundwater science. The essence of his long career over the last five decades was to promote the practice, teaching and research of hydrogeology to solve social problems and challenges via an environmental, sustainable and ethical approach. In his own words: “Water is a unique resource: a drop can save a life, in war and peace”.

The aac(6')-Ib-cr gene has been described in plasmids from CTX-M-15-producing Escherichia coli in the worldwide ST131 lineage, but has not been systematically sought in other quinolone-resistant strains in the UK. A rise in quinolone resistance in bacteraemia isolates in the UK preceded the increased prevalence of CTX-M-producing strains. This study aimed to describe the presence of plasmid-encoded quinolone resistance genes in historical and current strains of E. coli not producing extended-spectrum beta-lactamases (ESBLs).Ciprofloxacin-resistant, non-ESBL-producing E. coli isolates included nationally distributed isolates from the BSAC UK bacteraemia surveillance programme between 2001 and 2005, urinary isolates from a regional project in 2000 and local strains in 2006. The aac(6')-Ib-cr gene was detected using PCR followed by restriction fragment length polymorphism analysis. Multiplex PCR was used to detect qnr genes. Isolates with aac(6')-Ib-cr were assessed for aminoglycoside susceptibilities and were serotyped.The prevalence of the aac(6')-Ib-cr gene was 3% and 9% in current local urinary and historic national bacteraemia quinolone-resistant non-ESBL-producing E. coli, respectively. Of 521 regional urinary E. coli isolates from 2000, 14 were norfloxacin-resistant, none of which carried the aac(6')-Ib-cr gene. National positive bacteraemia isolates from 2001/2 were type O102-ST405 and, in 2004/5, types O1-ST645 and O25-ST131. Positive local urinary isolates from 2006 included serotypes O1 and O25.In the UK, aac(6')-Ib-cr occurs in E. coli in the absence of CTX-M-15, but with a restricted serotype distribution. Its presence in widespread bacteraemia isolates of a single type from 2001 to 2002, prior to the spread of CTX-M-15 in Britain, might suggest a lineage from which plasmid recombination occurred in man or other species.

Objectives: Catheter blockage by crystalline Proteus mirabilis biofilm is a common complication in patients undergoing long-term indwelling bladder catheterisation. Previously we have shown that inflating the retention balloons of all-silicone catheters with triclosan solutions prevents the encrustation process. The aim of the present work was to examine whether this strategy is effective in latex-based catheters. Methods: Laboratory bladder models were fitted with catheters and the retention balloons inflated with water or various concentrations of triclosan. The urine was inoculated with Pr. mirabilis and the times catheters took to block recorded. Results: Control catheters blocked in mean times ranging from 18 to 27h. The pH of the urine rose from 6.1 to >8.6. In models with latex-based catheters inflated with 1–10mg/ml triclosan, the urinary pH was controlled, the numbers of organisms in the urine was reduced and the catheters drained freely for the 7 day experimental period. Electron microscopy confirmed that crystalline biofilm was blocking control catheters. Little sign of encrustation was visible on the test catheters. Conclusion: Inflating the retention balloons with triclosan could have practical applications in controlling encrustation on both latex and silicone-based catheters.

Objectives: To examine (i) the effect of triclosan on the formation of catheter biofilms by urinary tract pathogens and (ii) the diffusion of triclosan through the retention balloons of urinary catheters. Methods: Models of the catheterized bladder were infected with eight different urinary tract pathogens and the effect of triclosan on biofilm formation was assessed by determining the numbers of viable cells colonizing the catheters and by scanning electron microscopy. HPLC was used to determine the triclosan concentration in urine draining from models that had been fitted with triclosan-inflated silicone catheters. Results: When catheters were inflated with triclosan (10 g/L) the formation of catheter biofilm by Escherichia coli, Klebsiella pneumoniae, Staphylococcus aureus and Proteus mirabilis was prevented. The numbers of Enterococcus faecalis and Providencia stuartii cells colonizing catheters were also significantly reduced (P < 0.05). Serratia marcescens, Morganella morganii and Pseudomonas aeruginosa, however, were able to produce extensive catheter biofilms in the presence of triclosan. Only P. mirabilis produced alkaline urine and encrusted the catheters. Concentrations of 0.02–0.16 mg/L of the biocide were detected in urine draining from the model over the 48 h experimental period. Conclusions: Triclosan diffused through silicone catheter balloons and produced urinary concentrations that prevented catheter encrustation by P. mirabilis and biofilm formation by several other common pathogens of the catheterized urinary tract. It had little effect on urease-producing P. aeruginosa, S. marcescens or M. morganii but these species did not produce alkaline urine or crystalline biofilms.

Catheter blockage by crystalline Proteus mirabilis biofilm is a common complication in patients undergoing long-term indwelling bladder catheterisation. Previously we have shown that inflating the retention balloons of all-silicone catheters with triclosan solutions prevents the encrustation process. The aim of the present work was to examine whether this strategy is effective in latex-based catheters.Laboratory bladder models were fitted with catheters and the retention balloons inflated with water or various concentrations of triclosan. The urine was inoculated with Pr. mirabilis and the times catheters took to block recorded.Control catheters blocked in mean times ranging from 18 to 27 h. The pH of the urine rose from 6.1 to8.6. In models with latex-based catheters inflated with 1-10 mg/ml triclosan, the urinary pH was controlled, the numbers of organisms in the urine was reduced and the catheters drained freely for the 7 day experimental period. Electron microscopy confirmed that crystalline biofilm was blocking control catheters. Little sign of encrustation was visible on the test catheters.Inflating the retention balloons with triclosan could have practical applications in controlling encrustation on both latex and silicone-based catheters.

Westphalen-type rearrangements of the 6α- and 6β-acetoxy-5α-hydroxy-4β-methyl compounds (10) and (7), the 5α-hydroxy-4β-methyl-6-oxo-compound (8), and the 6β-acetoxy-5α-hydroxy-4α-methyl compound (14) are reported. The 6α-acetoxy-5α-hydroxy-4α-methyl compound (12) is dehydrated to give the Δ4-compound (27), and the 5α-hydroxy-4α-methyl-6-oxo-compound (15) gives the 5α-acetate (29) and the Δ4-compound (28). These results and rate data for the reactions of compounds (10) and (14) suggest the possibility of the rearrangement proceeding with a synchronous methyl migration and C(5)–O cleavage.

6-Aminocholest-4,6-dien-3-one and 2-amino-5α-cholest-1-en-3-one are formed from 6α-azidocholest-4-en-3-one and 2β-azido-5α-cholestan-3-one respectively. Spectroscopic data are reported for these enamines.

The 6α-acetoxy-, 6β-acetoxy-, and 6-oxo-5α-hydroxy-4,4-dimethyl-steroids (9), (10), and (11) undergo Westphalen-type rearrangement to give the corresponding 5β-methyl-Δ9-compounds. The 6-deoxy-5α-hydroxy-4,4-dimethyl-compound (12) gives the Δ5-compound.

The backbone rearrangement of 10β-hydroxy-5βmethyl-19-nor-steroids is susceptible to changes in substituents at C(6) and to changes in the reaction medium. 9α-Hydroxy-5β-methyl-19-nor- and 10α-hydroxy-5β-methyl-19-nor-9β-steroids are simply dehydrated. The mechanisms of the backbone and the related Westphalen rearrangements are discussed. An anthrasteroid rearrangement of a 10β-hydroxy-5β-methyl-6-oxo-19-nor-steroid is reported.

Bei der bereits fruher versuchten Retroaldolisierung des Hydroxyketons (I) entsteht uber das Cholestenon (II) ein instabiles Zwischenprodukt, das als das Enamin (III) identifiziert wird.

Dehydration of a 6β,-10β-dihydroxy-5β-methyl-19-nor-steroid and a 10β-hydroxy-6-oxo-5β-methyl-19-nor-steroid gives backbone-rearranged products.

Treatment of the 6β-acetoxy-8β,9β-epoxy-11-ketone (2) with methanolic potassium hydroxide solution gave the 8,9-seco-6ξ-methoxy-8,11-diketone (3).

The rearrangement of the 19-methyl-5α-hydroxy-steroid (4) to the 5β-ethyl-Δ9,10-compound (5) occurs at a rate 5·3 times greater than the analogous rearrangement of the 5α-hydroxy-steroid (1) to the 5β-methyl-Δ9,10-compound (2).

Evidence for the in vivo incorporation of the S-methyl group of methionine into cholesterol and cholest-7-en-3β-ol in normal and tumorous rats is presented.