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The metabolic syndrome, in which cardiovascular disease and obesity play major roles, has become an important healthcare issue. Systemic concentrations of asymmetric dimethylarginine (ADMA) correlate with obesity and insulin resistance and it is considered to be an independent marker of cardiovascular disease. Currently, ADMA is understood to be an endogenous inhibitor of nitric oxide synthase; however, the direct effect of ADMA on adipocytes and in obesity has not been investigated. Here, we establish that ADMA in adipocytes regulates the expression and activity of the mTOR lipid synthesis pathway which results in adipocyte hypertrophy both in vitro and in vivo. Treatment of 3T3-L1 adipocytes with ADMA (10μM) resulted in adipocyte hypertrophy (control 27μm2 ±1.4, 10μM ADMA 33μm2± 1.6). This could not be mimicked through the blockade of NO by L-NAME (28μm2 ± 1.5) and PB-ITU (25μm2± 1.2). Hypertrophy was driven by an increase in mTOR expression (x2.4 ± 0.4) which upregulates ACC (x4.6 ± 0.8) and FASN (x1.4 ± 0.1) suggesting ADMA increases lipid production in an NO-independent manner. Investigations in vivo were explored through the genetic manipulation of DDAH1, an enzyme responsible for ADMA breakdown. Specific deletion of DDAH1 within adipocytes increased intracellular ADMA concentrations. This in turn caused an upregulation of mTOR, ACC and FASN expression and resulted in adipocyte hypertrophy. Conversely, genetic overexpression of DDAH1 reduced ADMA production within adipocytes and caused a down-regulation in mTOR expression. These data suggests that ADMA is a novel regulator of mTOR expression and activity at physiological concentrations. Pathological concentrations of ADMA are associated with adipocyte hypertrophy a known risk factor for insulin resistance and inflammation.

Urinary catheters and legs bags were simultaneously colonized by Escherichia coli and Proteus vulgaris using a model urinary drainage system. the system was continuously supplied with filter-sterilized artificial urine using a diurnal flow pattern. The extent of colonization was determined by assessment of both planktonic and biofilm formation over time. Contamination of the catheters resulted in rapid colonization of the whole system within a 24 h period. Contamination of the leg bags resulted in an ascending biofilm formation over a four-day period. Results indicated that infection risk could be minimized by changing the catheter and leg bags at least once a week. The design of the leg bags was not found to influence the rate or extent of biofilm formation.

Replication-deficient adenovirus (Ad) vectors provide an efficient technology for direct DNA delivery to cells both in vitro and in vivo. We have inserted the measles virus nucleoprotein (N) gene under the control of the strong constitutive CMV major IE promoter into an Ad type 5 E1- vector to produce the recombinant virus RAd68. Following infection of human fibroblasts with RAd68 in vitro, recombinant N protein was synthesized as a 60-kDa protein that represented up to 20% total soluble cell protein. Long filamentous structures were produced in both the nucleus and the cytoplasm that were similar in appearance to measles virus nucleocapsids. These "nucleocapsid-like" structures were readily purified by density gradient centrifugation. Murine immunization with RAd68 elicited (i) a humoral immune response to N, (ii) a major histocompatibility complex class I-restricted, antigen-specific cytotoxic T cell response, and (iii) protection against challenge with the measles virus CAM/RB strain in mice. This study demonstrates the capacity of replication-deficient Ad recombinants both to induce and to characterize cell-mediated immune responses.

A two-stage chemostat model of a plumbing system was developed, with tap water as the sole nutrient source. The model system was populated with a naturally occurring inoculum derived from an outbreak of Legionnaires' disease and containing Legionella pneumophila along with associated bacteria and protozoa. The model system was used to develop biofilms on the surfaces of a range of eight plumbing materials under controlled, reproducible conditions. The materials varied in their abilities to support biofilm development and the growth of L. pneumophila. Elastomeric surfaces had the most abundant biofilms supporting the highest numbers of L. pneumophila CFU; this was attributed to the leaching of nutrients for bacterial growth from the materials. No direct relationship existed between total biofouling and the numbers of L. pneumophila CFU.

Survival and growth of Legionella pneumophila in both biofilm and planktonic phases were determined with a two-stage model system. The model used filter-sterilized tap water as the sole source of nutrient to culture a naturally occurring mixed population of microorganisms including virulent L. pneumophila. At 20 degrees C, L. pneumophila accounted for a low proportion of biofilm flora on polybutylene and chlorinated polyvinyl chloride, but was absent from copper surfaces. The pathogen was most abundant on biofilms on plastics at 40 degrees C, where it accounted for up to 50% of the total biofilm flora. Copper surfaces were inhibitory to total biofouling and included only low numbers of L. pneumophila organisms. The pathogen was able to survive in biofilms on the surface of the plastic materials at 50 degrees C, but was absent from the copper surfaces at the same temperature. L. pneumophila could not be detected in the model system at 60 degrees C. In the presence of copper surfaces, biofilms forming on adjacent control glass surfaces were found to incorporate copper ions which subsequently inhibited colonization of their surfaces. This work suggests that the use of copper tubing in water systems may help to limit the colonization of water systems by L. pneumophila.

Algal toxins, as Microcystins released in water supplies, may represent a serious health hazard. The behaviour of primary hepatocytes was compared with that of immortalized liver cells, with the intention of providing a new test on Microcystin cellular toxicity. Immortalized liver cells were obtained by transfection with SV40 Large T antigen-bearing plasmids. Primary hepatocytes were used as a reference. Microcystin-LR at 10(-6), 10(-7)and 10(-9)m was added to hepatocytes maintained in suspension or cultured as three-dimensional hepatospheroids for 20 and 90 min at 37 degrees C. Toxic effects were monitored by cytoskeletal disruption ('blebs') using both light and scanning electron microscopy (SEM), lactate dehydrogenase release (LDH) and trypan blue dye exclusion test. Microcystin-LR at all doses induced bleb formation and a loss of microvilli in both primary hepatocytes and immortalized cell suspensions in comparison with controls. A high level of blebbed cells was detected in the absence of increased LDH release. The blebbing phenomenon was readily detectable by light microscopy but its morpho-complexity was unmasked by SEM, with early toxic events being indentified as loss of microvilli prior to bleb formation. Cells of primary hepatospheroids appeared to be less tightly attached to each other and more likely to bleb than immortalized ones. These immortalized cells could limit the use of primary cells and increase the reproducibility of the assay.

Two strains of Legionella pneumophila serogroup 1 monoclonal subgroup Pontiac were grown for the first time in continuous culture using a chemically defined medium. The influence of temperature on physiology and morphology was investigated by fixing the growth rate (equal to the dilution rate, D) at 0.08 h-1 and controlling the pH and dissolved oxygen concentration of the culture. Serine provided the principal source of carbon and energy but growth was limited by tyrosine. The bacterium behaved as a microaerophile in this medium, with maximal growth occurring at 0.31 (mg O2)I-1 (equivalent to a dissolved oxygen tension of 4% (v/v) air saturation at 30 degrees C). The cultures consisted of flagellated, short rods at 24 degrees C, but exhibited an increased level of pleomorphism and the loss of flagella as the temperature was increased to 37 degrees C. The presence of intracellular granules was noted, and their abundance was temperature-dependent. Polyhydroxybutyrate was present in L. pneumophila, and the proportion of the cell dry weight that it accounted for varied with temperature, being maximal at 24 degrees C. The ratio of saturated to unsaturated fatty acids in the cells decreased as the temperature was reduced towards 24 degrees C, so as to maintain membrane fluidity at low growth temperature.

A survey was undertaken to compare the hot-water systms of four Scottish institutional buildings, two of which suffered severe corrosion of their copper pipe work. A number of parameters were investigated including temperature, dissolved oxygen concentration (DO) and assimilable organic carbon (AOC). Microbiological analysis was also carried out on the water supply and the inner surface of the pipes. The institutional buildings experiencing corrosion had a lower temperature and a higher AOC in their hot-water systems than those without this particular problem. These findings were similar to a 1987 survey, which suggested that the problem might be microbially induced corrosion. A two-stage continuous culture model was used to mimic the corrosive environment of one of the institutional buildings. Using a microbial inoculum from the surface of the copper pipe work and filter sterilised water supplying the building it was possible to show that biofilm could readily be established up to 55°C. However at temperatures above 55°C the biofilm was greatly reduced.

Summary The incidence of food-poisoning caused by Salmonella serotype Enteritidis PT4 has increased. Implicated food products display pH levels between 4 and 9. Accordingly, the effect of growth at extremes of pH on the presence of surface structures and the carriage of a 38-MDa plasmid was determined by growing a clinical isolate of Enteritidis PT4 in a chemostat. Steady-state growth was possible over the pH range 4.35-9.45, corresponding to the pH extremes associated with key reservoirs implicated in outbreaks. Without pH control, cultures stabilised at pH 7.10. Growth at extremes of pH had significant effects on the distribution of cell surface structures; at pH 9.45, only 3% of cells were fimbriate compared with 52% at pH 7.10 and 20% at pH 4.35. The proportion of motile cells and the presence of flagella was also reduced at extremes of pH. A 38-MDa plasmid was present in cells grown in the chemostat at pH 7.10, but not in cells grown at pH 4.35 or pH 9.45. Thus, environmental pH may have a significant impact on the virulence potential of Enteritidis PT4.

A three-stage chemostat containing a mixed consortium of microorganisms, including Legionella pneumophila, was used to determine the suitability of a silver-containing paint to control biofouling in water systems. The paint was efficient in controlling total surface colonisation by heterotrophic microorganisms and growth of the pathogen over a 2-week period. Biodiversity was limited in the presence of the silver paint and this was thought to help control L. pneumophila numbers. Glass control tiles suspended alongside the silver painted tiles also had reduced colonisation for the 2-week period, suggesting that low levels of silver leached from the paint surface. This loss of silver was confirmed since the inhibition of biofouling and inclusion of the pathogen was not maintained after the 2-week period. Although this paint was unsuitable for controlling biofouling over extended time periods, the data suggest that a reformulated paint or electrochemical method of introducing silver ions may be successful.

A replication deficient adenovirus containing the measles virus N gene (nucleoprotein) was propagated on a specially constructed mammalian helper cell line (293), and used to infect a target cell population (MRC5) where expression of the cloned gene only is obtained from the strong CMV IE promoter. Electron microscopy showed that the N protein accumulates in both the cytoplasm and nucleus of infected cells. The growth of 293 cells was compared in a variety of cell culture systems including static flasks, cell aggregates and a variety of microcarriers. The best results were achieved using the Fibra-cel carrier. Virus yields were comparable with the Fibra-cel carriers, cell aggregates and static flasks.

The gene encoding the major nucleocapsid, N, protein of measles virus has been inserted into a baculovirus vector under the control of the polyhedrin promoter. Insect cells infected with this recombinant baculovirus synthesize high levels of measles N protein, up to 40% of total soluble cell protein. The recombinant protein is recognized by sera from convalescent patients, vaccinees and patients with subacute sclerosing panencephalitis and thus could form the basis of a simple diagnostic assay. Nucleocapsid-like structures, similar to those found in mammalian cells infected with measles virus, can be observed in both the nucleus and cytoplasm of the infected insect cells. These have many structural features in common with nucleocapsids found in measles virus-infected cells, but are longer (up to 2 microns) and have a lower buoyant density. Measles N protein thus appears to be capable of assembling into nucleocapsid-like structures in the absence of measles virion RNA or other viral proteins.

The major extracellular enzyme of Legionella pneumophila, a metalloprotease, has been proposed as a pathogenic factor in Legionnaires' disease due to its cytotoxic, tissue-destructive, and phagocyte-inhibitory properties. The relevance of these activities depends on the production of the protease during infection, i.e. by L. pneumophila multiplying intracellularly. In this study, L. pneumophila was demonstrated to produce protease in guinea-pig and human alveolar macrophages infected in vitro. After 24 h infection, approximately 0.1 to 0.2 micrograms of protease per 10(6) bacteria was measured by ELISA in culture supernatants and lysates of the infected cells, whereas no protease could be detected immediately after infection. Immunogold labelling using anti-protease antibody showed the enzyme to be located within phagosomes and distributed throughout the macrophages. Recent observations have shown that this protease could modify host defence mechanisms through inhibition of bacterial killing by neutrophils and monocytes. The intracellular production of the enzyme in infected macrophages demonstrated here further supports a role for the protease in the pathogenesis of Legionnaires' disease.

Pneumocystis carinii pneumonia occurred in 6 of 17 rhesus monkeys infected with simian immunodeficiency virus and was studied by immunohistochemistry and by scanning and transmission electron microscopy. A monoclonal antibody/streptavidin-biotin-peroxidase staining method was highly sensitive for detecting the organisms in small, early lesions and was much more sensitive and specific than traditional silver impregnation methods. Reprocessing of paraffin wax-embedded lung tissue for scanning electron microscopy and use of a video printer to produce a photographic montage of light microscopic lesions allowed the same areas of tissue to be examined and compared by both methods. The ultrastructural morphology of P. carinii in the rhesus monkey was identical to that in man, as were the histological and electron microscopic lesions, including pulmonary fibrosis. Trophozoites were seen attached to alveolar type I epithelium mainly by intimate apposition to the plasma membrane, but scanning electron microscopy also showed attachment by elongated filopodia. Few macrophages were present in infected alveoli, and though phagocytosis followed by digestion of P. carinii trophozoites was observed, it appeared to occur at a very low level.

Summary Pulmonary interstitial fibrosis commenced as focal proliferation of fibroblasts and accumulation of macrophages in interalveolar septa and was followed by deposition of excess collagen. Epithelium of airways and alveoli remained normal. Perivascular nodules of lymphoid tissue which developed in the lungs of many older animals had a high mitotic rate, but the lymphocytes were morphologically normal. Micro-organisms were not observed in the lungs of any animal. In a previous publication (Baskerville, Baskerville & Wood, 1982) we described histopathological and bacteriological studies of naturally-occurring chronic pneumonia in a colony of guineapigs. The lesions were of two main types, pulmonary interstitial fibrosis (PIF) and perivascular lymphoid hyperplasia (PVL). No correlation was found between the presence of Bordetella bronchiseptica or other bacteria and the development of the pulmonary lesions, and their aetiology remains unknown. A detailed electron microscopical study was therefore undertaken to determine the nature and pathogenesis of these chronic lesions and to search for evidence of other possible causative agents, in particular mycoplasmas and viruses.

Deposition of fine sediment contaminated by heavy metals on floodplains in the Tyne basin, north-east England, during a major flood in August 1986 provided an unusual opportunity to investigate the chemical and physical speciation of metals in overbank fines. Selective extractions and heavy-liquid analyses were used to assess the chemical forms of sediment-associated metal and the relationship between grain size, density and metal concentration and to identify sources of metalliferous material. Generally the highest concentrations of trace metals were found in the 500–250 μm size range and in the heavier density fractions (>3.3 gml−1), though more than 60% of metals reported to the lightest (

Using immunocytochemical techniques at the light and electron microscope levels, Legionella pneumophila and one of its extracellular proteases were located in the lungs of guinea pigs with experimental Legionnaires' disease (LD). L. pneumophila was immunostained by several peroxidase- and gold-labelling methods for light and electron microscopy. The protease was immunolabelled in tissue fixed in Carnoy's fluid at the light microscopical level and on broth-grown organisms at the ultrastructural level. It was not labelled in either formalin- or glutaraldehyde-fixed tissue. Using double-labelling techniques, L. pneumophila and protease were located in the same section and were shown to be intimately associated with pulmonary lesions, providing strong evidence for the role of this protease in LD pneumonia.

Bacteroides gingivalis W50 was grown in a chemostat under steady-state conditions at pH 7.5 +/- 0.2 and a constant growth rate of 6.9 h for periods of up to 6 weeks (146 bacterial generations) in a complex medium. Hemin was capable of limiting the growth of cells up to a concentration of approximately 0.5 micrograms/ml since higher concentrations of hemin did not increase cell yields; cells grew in the absence of exogenously added vitamin K1. Only a limited number of amino acids was metabolized during growth, but because none of these was totally depleted, the limiting nutrient under hemin excess conditions was probably a peptide. A range of fermentation products was produced under all conditions of growth; higher concentrations of cytotoxic metabolites such as propionate and butyrate were formed under hemin excess conditions, although more ammonia was released under hemin limitation. When viewed by electron microscopy, cells grown under hemin limitation appeared to be either coccobacillary or short rods and possessed few fimbriae per cell, but large numbers of extracellular vesicles could be seen both surrounding the cell surface and free in the environment. In contrast, cells grown under hemin excess conditions were more commonly coccus shaped and were more heavily fimbriated but had fewer extracellular vesicles. Marked differences were found in the susceptibility of mice to infection with cells grown under different concentrations of hemin. Cells transferred to media without any added hemin were avirulent, whereas those grown under conditions of hemin limitation (0.33 and 0.40 micrograms/ml) produced a 20 and 50% mortality in mice, respectively. In contrast cells grown under hemin excess always caused 100% mortality in mice, although this virulence was dose dependent. When virulent, the bacteria caused an extensive, spreading infection with necrosis of the skin and subcutaneous tissues. Collagen disintegration was seen histologically, implying a role for collagenase production in the pathogenicity of these bacteria.

The ultrastructure and enzyme activity of an avirulent, weakly-pigmenting, colonial variant (W50/BE1) was compared with that of the highly-virulent parent strain, Bacteroides gingivalis W50, in an attempt to identify significant virulence factors. Electron microscopy of thin sections of the organisms showed strain W50 to possess a 3-4-fold thicker layer of material external to the outer membrane. No significant differences between the strains were found with respect to collagen- or hyaluronic acid-breakdown activities at assay pH 7.5. However, cultures of strain W50 had over 3-fold more trypsin-like activity (P less than 0.01) than the avirulent variant. These results, when taken with other data, suggest that a thick external layer on the cell surface together with high trypsin-like activity might be important virulence factors of B. gingivalis.

Intranasal (or intratracheal) administration of a tissue-destructive protease from Legionella pneumophila to guinea-pigs produced areas of haemorrhagic pneumonia in the lungs after 1/2 h. By 24 h there was confluent consolidation in all lobes. Histological and ultrastructural studies showed alveolar haemorrhage, vesiculation and necrosis of type I alveolar epithelium and endothelium, followed by progressive exudation of oedema fluid, fibrin, PMN and macrophages. Damage to type II cell lamellated bodies and discharge of lamellar material were significant features of the lesion. Collagenase activity was indicated by morphological degradation of collagen fibres in severely affected interalveolar septa. The pathological changes of Legionnaires' disease pneumonia can thus be reproduced experimentally by the administration of a L. pneumophila tissue-destructive protease, suggesting that production of this protease in vivo during L. pneumophila infection may play an important role in causing the pneumonia.

The organs of monkeys infected with Ebola haemorrhagic fever were examined by light and electron microscopy during the acute stage of the disease. The virus caused focal coagulative necrosis in the liver, spleen, kidney, lung and testis and widespread mild vascular damage. In the brain there was intense congestion, with erythrocyte 'sludging', but no inflammatory reaction. There was significant injury to the microvasculature in all organs. Virus replicated in endothelial cytoplasm causing focal necrosis, separation of tight junctions and detachment from basement membranes. These changes were associated with oedema and haemorrhage, but though contributing to the hypovolaemic shock were not sufficiently extensive to account for the severity of vascular collapse. Renal involvement was also clinically important. Some renal cellular injury was caused by direct virus invasion of glomerular endothelium and tubular epithelium, but much tubular damage was probably due to ischaemia resulting from thrombosis in the peritubular capillaries. The virus also replicated in lymphocytes and monocytes and in interstitial cells of the testis. Since particles were not found in seminiferous epithelium, the degeneration of spermatogonia and spermatocytes was probably secondary to ischaemia.

The widely held view that the filamentous hemagglutinin (FHA) of Bordetella pertussis is derived from fimbriae (pili) is not supported by studies of fimbriation and FHA content of the organism. Fimbriae do not label specifically with antibody to FHA in immuno-electron microscopy but do label with antibody to serotype-specific agglutinogen.

Guinea-pigs were exposed for 14 days to an aerosol of titanium dioxide (TiO2) dust to produce macrophage blockade. Groups of the animals were later infected by aerosol with Legionella pneumophila. Histological and ultrastructural studies showed that TiO2 dust alone was inert and non-fibrogenic and even at 6 weeks induced no pathological lesions in the lungs, apart from accumulation of macrophages in interalveolar septa. The macrophage blockade by TiO2 did not alter the animals' susceptibility to Legionnaires' disease nor increase mortality. The blockade was effective in the early stages of the infection and limited multiplication of L. pneumophila in the lungs. Later blood monocytes were recruited into the lungs, where they phagocytosed Legionellae, resulting in lung counts comparable to those of TiO2-free control animals.

Twenty-four thermophilic bacteriophages have been isolated from diverse sources such as compost, soil, silage and rotting straw. Although considerable individual host specificity was observed, the phages were able to infect most of the major taxonomic groups of Bacillus thermophiles. The phages varied considerably in morphology and size; the phage heads were either cylindrical or polyhedral with tails varying in length between 15 and 500 nm. Most of the phages were stable at 50 degrees C for 4-5 h but at 70 degrees C the plaque-forming units decreased by between 10(2)- and 10(7)-fold in 2 h. The DNA of morphologically similar phages was examined by restriction enzyme analysis, and some differences in the DNA fragment patterns were found. Efficiency of plating data indicated that 'B. caldotenax' has a restriction and modification system. These phages may be valuable for the study of the genetics of thermophilic bacilli: transduction of 'B. caldotenax' and 'B. caldovelox' by phage JS017 has been observed.

Guinea pigs, rhesus monkeys and marmosets infected with Legionella pneumophila in small particle aerosols developed an acute fibrinopurulent bronchopneumonia. Changes from 24 hr included exudation into alveoli of protein-rich, often fibrinous fluid and many polymorphonuclear leucocytes (PMN) and macrophages. Damage to alveolar capillary endothelium consisted of widespread cytoplasmic swelling and vesiculation, but necrosis of endothelium and the associated alveolar epithelium was focal and less common. Phagocytosis of L. pneumophila organisms was predominantly by macrophages, but the bacteria were also seen in PMN. Free organisms were present in alveoli and capillary lumina at all stages of the infection but were not observed in lung parenchymal cells. Some infected macrophages and PMN became necrotic and lysed to release intact bacteria. In all species of experimental animal, intracytoplasmic aggregations of granular material, believed to be glycogen, were seen frequently in macrophages and PMN which had phagocytosed L. pneumophila. These deposits of glycogen may reflect either an increased energy demand by the host cell or an interference with its carbohydrate metabolism.

An HIV-1 isolate (designated GB8) was isolated from an asymptomatic AIDS patient and subsequently grown in the T-lymphocyte cell line JM. Electron microscopy showed that it is vesicles within the syncytia present in cultures of JM cells chronically infected with GB8, rather than the surface membranes of unfused cells, which are the major sites for the assembly, production and release of HIV.

A chemostat system has been developed to model the attachment of oral bacteria, and the subsequent development of plaque film, to acrylic surfaces immersed in steady state cultures. Plaque was removed from the teeth and gingival margin of volunteers who refrained from oral hygiene for at least 72 h. Samples were pooled and inoculated into a complex growth medium maintained at 37 degrees C. Glucose-limited continuous culture was established at a dilution rate of 0.05/h and at pH 7.0. Microbiological analysis of the culture indicated that a complex community of oral bacteria was established, typical of that found in dental plaque. Acrylic tiles were immersed in the fermenter through a modified fermenter head and incubated therein for up to 21 d. Scanning electron microscopy showed that either side of the tiles contained a rough and a smooth surface and these initially favoured the attachment of fusiform bacteria, particularly on the rough surface. Cocci attached to those surfaces which were not heavily colonized by the fusiforms and eventually grew into and on the colonial sheets of the fusiforms.

Immuno-electron microscopy using colloidal gold-tagged monoclonal antibodies (McAbs) has been used to detect antigens on the surface of Bordetella pertussis cells. McAbs to serotype-specific agglutinogens 2 and 3 labelled fimbriae in a serotype-specific manner. An attempt was made to determine whether individual fimbriae of serotype 1.2.3 cells bear both antigens 2 and 3. In double labelling experiments, individual cells were found to label with McAbs to antigen 2 (3 nm gold) and to antigen 3 (15 nm gold). Many fimbriae labelled with only one of these reagents, but there were instances where both labels could have been attached to the same fimbria. No fimbrial labelling was obtained with McAb to agglutinogen 1. Gold-tagged McAbs to filamentous haemagglutinin (FHA) labelled neither the fimbriae nor the surface of B. pertussis cells. Unfixed cells on electron microscope grids appeared to shed FHA readily. After fixation, a small proportion of cells bore aggregates of FHA which labelled specifically with anti-FHA McAb-gold. Results with one McAb to lymphocytosis promoting factor indicated that this antigen may be more intimately associated with the surface of B. pertussis than is FHA.