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PubMed1996

Histopathology of bone marrow after allogeneic bone marrow transplantation for chronic myeloid leukaemia.

The histopathology of bone marrow after allogeneic bone marrow transplantation for chronic myeloid leukaemia (CML) was studied in 20 bone marrow biopsy specimens from 14 patients. Biopsies were performed at day 30 post-transplantion (5 biopsies), between day 90 and day 100 (14 biopsies), and one year post-transplantation (1 biopsy). Eight biopsies taken at day 30 post-transplantation for lymphoproliferative disorder were studied as controls. Granulopoiesis was predominant in all day 30 bone marrows in patients treated for CML. In 2 cases, rejection was suspected because of marrow hypoplasia at day 30: one case developed acute leukaemia soon after persistant hypoplasia at day 90 while the evolution of the other case was good. Two day 30 biopsies showed granulocytic hyperplasia but follow-up proved complete remission of CML. Thus, in our series, early biopsies at day 30 did not have any prognostic value. Twelve cases at day 90-100 showed little modifications, such as minor dyserythropoiesis and dysmegakaryopoiesis. One case showed granulocytic hyperplasia at day 100 but bone marrow was normal one year later and the patient in complete remission. The haematopoietic reconstitution after allogeneic bone marrow transplantation may present a transient granulocytic hyperplasia that must not be diagnosed as a persistence of CML.

Adult↗
PubMed2004

Mid- to low-frequency Fourier transform infrared spectra of S-state cycle for photosynthetic water oxidation in Synechocystis sp. PCC 6803.

Flash-induced Fourier transform infrared (FTIR) difference spectra for the four-step S-state cycle and the effects of global (15)N- and (13)C-isotope labeling on the difference spectra were examined for the first time in the mid- to low-frequency (1200-800 cm(-1)) as well as the mid-frequency (1700-1200 cm(-1)) regions using photosystem (PS) II core particles from cyanobacterium Synechocystis sp. PCC 6803. The difference spectra clearly exhibited the characteristic vibrational features for each transition during the S-state cycling. It is likely that the bands that change their sign and intensity with the S-state advances reflect the changes of the amino acid residues and protein matrices that have functional and/or structural roles within the oxygen-evolving complex (OEC). Except for some minor differences, the trends of S-state dependence in the 1700-1200 cm(-1) frequency spectra of the PS II cores from Synechocystis were comparable to that of spinach, indicating that the structural changes of the polypeptide backbones and amino acid side chains that occur during the oxygen evolution are inherently identical between cyanobacteria and higher plants. Upon (13)C-labeling, most of the bands, including amide I and II modes and carboxylate stretching modes, showed downward shifts; in contrast, (15)N-labeling induced isotopic shifts that were predominantly observed in the amide II region. In the mid- to low-frequency region, several bands in the 1200-1140 cm(-1) region were attributable to the nitrogen- and/or carbon-containing group(s) that are closely related to the oxygen evolution process. Specifically, the putative histidine ligand exhibited a band at 1113 cm(-1) which was affected by both (15)N- and (13)C-labeling and showed distinct S-state dependency. The light-induced bands in the 900-800 cm(-1) region were downshifted only by (13)C-labeling, whereas the bands in the 1000-900 cm(-1) region were affected by both (15)N- and (13)C-labeling. Several modes in the mid- to low-frequency spectra were induced by the change in protonation state of the buffer molecules accompanied by S-state transitions. Our studies on the light-induced spectrum showed that contributions from the redox changes of Q(A) and the non-heme iron at the acceptor side and Y(D) were minimal. It was, therefore, suggested that the observed bands in the 1000-800 cm(-1) region include the modes of the amino acid side chains that are coupled to the oxidation of the Mn cluster. S-state-dependent changes were observed in some of the bands.

Cyanobacteria↗
PubMed1992

Evolution of the human immunodeficiency virus epidemic among patients attending sexually transmitted disease clinics: a decade of experience.

Since human immunodeficiency virus (HIV) is predominantly sexually transmitted, serologic surveys for HIV infection in sexually transmitted disease (STD) clinics provide sentinel observations regarding HIV epidemiology. Over the past decade, 17,207 systematically collected sera from patients attending Baltimore STD clinics were analyzed. From 1979 through 1989, HIV seroprevalence rose from 0.23% to 5.35%, increasing significantly in both men and women (P less than .001). Due to a marked increase in HIV infection among women during the mid-1980s, the male-to-female ratio of HIV infection declined from 16:1 in 1979-1982 to 1.0 in 1988-1989. HIV seroprevalence increased significantly (P less than .001) in all age groups, with the greatest increase among teenagers, rising from 0.18% in 1979-1983 to 2.1% in 1987-1989 (P less than .001). Although HIV seroprevalence was higher among whites than blacks during the early 1980s, it increased in blacks subsequently (P less than .001), eventually resulting in a greater rate among black than white clinic patients (P less than .01). These data reflect the evolution of the HIV epidemic in US inner cities. HIV prevalence has increased greater than 20-fold, with recent increases being most marked among women, teenagers, and blacks. Additional resources will undoubtedly be required to support further intensive behavioral and educational programs targeted at adolescents and inner-city minorities.

Adolescent↗
PubMed2003

Perspective: Genetic assimilation and a possible evolutionary paradox: can macroevolution sometimes be so fast as to pass us by?

The idea of genetic assimilation, that environmentally induced phenotypes may become genetically fixed and no longer require the original environmental stimulus, has had varied success through time in evolutionary biology research. Proposed by Waddington in the 1940s, it became an area of active empirical research mostly thanks to the efforts of its inventor and his collaborators. It was then attacked as of minor importance during the "hardening" of the neo-Darwinian synthesis and was relegated to a secondary role for decades. Recently, several papers have appeared, mostly independently of each other, to explore the likelihood of genetic assimilation as a biological phenomenon and its potential importance to our understanding of evolution. In this article we briefly trace the history of the concept and then discuss theoretical models that have newly employed genetic assimilation in a variety of contexts. We propose a typical scenario of evolution of genetic assimilation via an intermediate stage of phenotypic plasticity and present potential examples of the same. We also discuss a conceptual map of current and future lines of research aimed at exploring the actual relevance of genetic assimilation for evolutionary biology.

Adaptation, Biological↗
PubMed2006

Nitric oxide-dependent killing of Cryptococcus neoformans by B-1-derived mononuclear phagocyte.

The role of B lymphocytes in protecting the host against pulmonary Cryptococcus neoformans infection is until now, uncertain. A recent study using B lymphocyte-deficient mice suggests that B lymphocytes play a protective role in cryptococcal infection. It has been well established that at least three B cell subsets, B-1a, B-1b, and B-2, are present in the mouse periphery. B-1 cells constitute a minor fraction of the B cell population in the spleen and are not detected in lymph nodes of mice. We demonstrated that B-1 cells migrate to a nonspecific, inflammatory focus and differentiate into macrophage-like cells. However, the role these cells might play on the kinetics and evolution of the inflammatory response and on fungal infection has not yet been established. Based on these data, we decided to investigate the interaction of B-1-derived mononuclear phagocytes (BDMP) with C. neoformans to elucidate the possible influence of this cell in the progression of the disease. In this study, we demonstrated that the BDMP cell internalized C. neoformans and that this process was mediated by complement receptor 3. Thus, our results showed that the BDMP cell was more fungicidal than a macrophage and up-regulated major histocompatibility complex type II and the CD86 costimulatory molecule with the production of proinflammatory cytokines. The phagocytosis of C. neoformans results in the nitric oxide (NO)-mediated death of the fungus, as demonstrated by experiments using NO synthase 2 knockout and aminoguanidine-treated, wild-type mice.

Animals↗
PubMed1996

Serial MRI, VEP, SEP and biotesiometry in acute optic neuritis: value of baseline results to predict the development of new lesions at one year follow up.

INTRODUCTION: In an attempt to establish the value of MRI, VEP, SEP, and biotesiometry in monitoring disease evolution we undertook a one year follow up study of 70 untreated patients with acute optic neuritis (ON). MATERIAL & METHODS: ON was monosymptomatic in 48 patients (bilateral in 10) and part of clinically definite multiple sclerosis (CDMS) in 22 patients, examined as mentioned below. RESULTS: Results are given at onset and at follow up (in brackets). In monosymptomatic ON, brain MRI was abnormal in 53% (53%), VEP in the eye with acute ON in 79% (71%), VEP in the clinically unaffected eye in 34% (47%), SEP in 25% (23%), and biotesiometry in 29% (17%). In CDMS, brain MRI was abnormal in 95% (95%), VEP in the eye with acute ON in 86% (77%), VEP in the clinically unaffected eye in 50% (64%), SEP in 55% (50%), and biotesiometry in 63% (53%). Only minor changes in test scores were observed after one year except for significant improvement of VEP in eyes with acute ON. Eight of 32 patients, characterized by at least one abnormal paraclinical test at onset of monosymptomatic ON, had developed CDMS versus none of 16 patients with normal paraclinical results (p = 0.03; Fisher). CONCLUSION: Patients with monosymptomatic ON with paraclinical signs of multifocal involvement at onset had an increased risk of developing CDMS. No single test predicted the evolution of CDMS, perhaps due to the relatively short follow up time.

Acute Disease↗
PubMed2000

Functional equivalence of the transcription factors Pax2 and Pax5 in mouse development.

Pax2 and Pax5 arose by gene duplication at the onset of vertebrate evolution and have since diverged in their developmental expression patterns. They are expressed in different organs of the mouse embryo except for their coexpression at the midbrain-hindbrain boundary (MHB), which functions as an organizing center to control midbrain and cerebellum development. During MHB development, Pax2 expression is initiated prior to Pax5 transcription, and Pax2(-/-) embryos fail to generate the posterior midbrain and cerebellum, whereas Pax5(-/-) mice exhibit only minor patterning defects in the same brain regions. To investigate whether these contrasting phenotypes are caused by differences in the temporal expression or biochemical activity of these two transcription factors, we have generated a knock-in (ki) mouse, which expresses a Pax5 minigene under the control of the Pax2 locus. Midbrain and cerebellum development was entirely rescued in Pax2(5ki/5ki) embryos. Pax5 could furthermore completely substitute for the Pax2 function during morphogenesis of the inner ear and genital tracts, despite the fact that the Pax5 transcript of the Pax2(5ki )allele was expressed only at a fivefold lower level than the wild-type Pax2 mRNA. As a consequence, the Pax2(5ki )allele was able to rescue most but not all Pax2 mutant defects in the developing eye and kidney, both of which are known to be highly sensitive to Pax2 protein dosage. Together these data demonstrate that the transcription factors Pax2 and Pax5 have maintained equivalent biochemical functions since their divergence early in vertebrate evolution.

Alleles↗
PubMed1997

Evolution of lactate dehydrogenase-A homologs of barracuda fishes (genus Sphyraena) from different thermal environments: differences in kinetic properties and thermal stability are due to amino acid substitutions outside the active site.

Orthologous homologs of lactate dehydrogenase-A (LDH-A) (EC 1.1.1.27; NAD+:lactate oxidoreductase) of six barracuda species (genus Sphyraena) display differences in Michaelis-Menten constants (apparent Km) for substrate (pyruvate) and cofactor (NADH) that reflect evolution at different habitat temperatures. Significant increases in Km with increasing measurement temperature occur for all homologs, yet Km at normal body temperatures is similar among species because of the inverse relationship between adaptation temperature and Km. Thermal stabilities of the homologs also differ. To determine the amino acid substitutions responsible for differences in Km and thermal stability, peptide mapping of the LDH-As of all six species was first performed. Then, the amino acid sequences of the three homologs having the most similar peptide maps, those of the north temperate species, S. argentea, the subtropical species, S. lucasana, and the south temperate species, S. idiastes, were deduced from the respective cDNA sequences. At most, there were four amino acid substitutions between any pair of species, none of which occurred in the loop or substrate binding sites of the enzymes. The sequence of LDH-A from S. lucasana differs from that of S. idiastes only at position 8. The homolog of S. argentea differs from the other two sequences at positions 8, 61, 68, and 223. We used a full-length cDNA clone of LDH-A of S. lucasana to test, by site-directed mutagenesis, the importance of these sequence changes in establishing the observed differences in kinetics and thermal stability. Differences in sequence at sites 61 and/or 68 appear to account for the differences in Km between the LDH-As of S. argentea and S. lucasana. Differences at position 8 appear to account for the difference in thermal stability between the homologs of S. argentea and S. lucasana. Evolutionary adaptation of proteins to temperature thus may be achieved by minor changes in sequence at locations outside of active sites, and these changes may independently affect kinetic properties and thermal stabilities.

Amino Acid Sequence↗
PubMed2006

A systematic search for positive selection in higher plants (Embryophytes).

BACKGROUND: Previously, a database characterizing examples of Embryophyte gene family lineages showing evidence of positive selection was reported. Of the gene family trees, 138 Embryophyte branches showed Ka/Ks>>1 and are candidates for functional adaptation. The database and these examples have now been studied in further detail to better understand the molecular basis for plant genome evolution. RESULTS: Neutral modeling showed an excess of positive and/or negative selection in the database over a neutral expectation centered on the mean Ka/Ks ratio. Out of 673 families with assigned structures, 490 have at least one branch with Ka/Ks >>1 in a region of the protein, enabling a picture of selective pressures delineated by protein structure. Most gene families allowed reconstruction back to the last common ancestor of flowering plants (Magnoliophytes) without saturation of 4- fold degenerate codon position. Positive selection occurred in a wide variety of gene families with different functions, including in the self incompatibility locus, in defense against pathogens, in embryogenesis, in cold acclimation, and in electrontransport. Structurally, selective pressures were similar between alpha-helices and beta- sheets, but were less negative and more variant on the surface and away from the hydrophobic core. CONCLUSION: Positive selection was detected statistically significantly in a small and nonrandom minority of gene families in a systematic analysis of embryophyte gene families. More sensitive methods increased the level of positive selection that was detected and presented a structural basis for the role of positive selection in plant genomes.

Adaptation, Physiological↗
PubMed2000

The nuclear matrix of Euglena gracilis (euglenophyta): a stage of nuclear matrix evolution?

Euglena gracilis cell was extracted sequentially with CSK-Triton buffer, RSB-Magik solution and DNase-As solution. DGD embedment-free electron microscopy showed that in the extracted nucleus there was a residual non-chromatin fibrous network. That it could not be removed by hot trichloroacetic acid further supported the idea that it was a non-histone, non-chromatin fibrous protein network, and should be the internal network of the nuclear matrix. After the sequential extraction, the nuclear membrane was removed, leaving behind a layer of lamina; the chromatin was digested and eluted from the dense chromosomes and residual chromosomal structures that should be chromosomal scaffold were revealed. Western blot analysis with antiserum against rat lamins showed that nuclear lamina of the cell possessed two positive polypeptides, a major one and a minor one, which had molecular masses similar to lamin B and lamin A, respectively. Comparing these data with those of the most primitive eukaryote Archezoa and of higher eukaryotes, it was suggested that the lower unicellular eukaryote E. gracilis already had the nuclear matrix structure, and its nuclear matrix (especially the lamina) might represent a stage of evolutionary history of the nuclear matrix.

Animals↗
PubMed1992

Acetylornithine deacetylase, succinyldiaminopimelate desuccinylase and carboxypeptidase G2 are evolutionarily related.

The nucleotide (nt) sequence of the Escherichia coli argE gene, encoding the acetylornithine deacetylase (AO) subunit, has been established and corresponds to a 43-kDa (M(r) 42,320) polypeptide. The enzyme has been purified to near homogeneity and it appears to be a dimer consisting of two 43-kDa subunits. The amino acid sequence deduced from the nt sequence was compared to that of the subunit of E. coli succinyldiaminopimelate desuccinylase (the dapE gene product involved in the diaminopimelate pathway for lysine biosynthesis), since both enzymes share functional and biochemical features. Significant similarity covering the entire sequence allows us to infer a common origin for both deacylases. This homology extends to the Pseudomonas sp. G2 carboxypeptidase (G2CP); this or a functionally related enzyme may be responsible for the minor AO activity found in organisms relying on ornithine acetyltransferase for ornithine biosynthesis.

Amidohydrolases↗
PubMed1997

Replication factor C interacts with the C-terminal side of proliferating cell nuclear antigen.

Replication factor C (RF-C) is a heteropentameric protein essential for DNA replication and repair. It is a molecular matchmaker required for loading of proliferating cell nuclear antigen (PCNA) onto double-stranded DNA and, thus, for PCNA-dependent DNA elongation by DNA polymerases delta and epsilon. To elucidate the mode of RF-C binding to the PCNA clamp, modified forms of human PCNA were used that could be 32P-labeled in vitro either at the C or the N terminus. Using a kinase protection assay, we show that the heteropentameric calf thymus RF-C was able to protect the C-terminal region but not the N-terminal region of human PCNA from phosphorylation, suggesting that RF-C interacts with the PCNA face at which the C termini are located (C-side). A similar protection profile was obtained with the recently identified PCNA binding region (residues 478-712), but not with the DNA binding region (residues 366-477), of the human RF-C large subunit (Fotedar, R., Mossi, R., Fitzgerald, P., Rousselle, T., Maga, G., Brickner, H., Messner, H., Khastilba, S., Hübscher, U., and Fotedar, A., (1996) EMBO J., 15, 4423-4433). Furthermore, we show that the RF-C 36 kDa subunit of human RF-C could interact independently with the C-side of PCNA. The RF-C large subunit from a third species, namely Drosophila melanogaster, interacted similarly with the modified human PCNA, indicating that the interaction between RF-C and PCNA is conserved through eukaryotic evolution.

Animals↗
PubMed2005

Expanding Southwest Pacific mitochondrial haplogroups P and Q.

Modern humans have occupied New Guinea and the nearby Bismarck and Solomon archipelagos of Island Melanesia for at least 40,000 years. Previous mitochondrial DNA (mtDNA) studies indicated that two common lineages in this region, haplogroups P and Q, were particularly diverse, with the coalescence for P considered significantly older than that for Q. In this study, we expand the definition of haplogroup Q so that it includes three major branches, each separated by multiple mutational distinctions (Q1, equivalent to the earlier definition of Q, plus Q2 and Q3). We report three whole-mtDNA genomes that establish Q2 as a major Q branch. In addition, we describe 314 control region sequences that belong to the expanded haplogroups P and Q from our Southwest Pacific collection. The coalescence dates for the largest P and Q branches (P1 and Q1) are similar to each other (approximately 50,000 years old) and considerably older than prior estimates. Newly identified Q2, which was found in Island Melanesian samples just to the east, is somewhat younger by more than 10,000 years. Our coalescence estimates should be more reliable than prior ones because they were based on significantly larger samples as well as complete mtDNA-coding region sequencing. Our estimates are roughly in accord with the current suggested dates for the first settlement of New Guinea-Sahul. The phylogeography of P and Q indicates almost total (female) isolation of ancient New Guinea-Island Melanesia from Australia that may have existed from the time of the first settlement. While Q subsequently diversified extensively in New Guinea-Island Melanesia, it has not been found in Australia. The only shared mtDNA haplogroup between Australia and New Guinea identified to date remains one minor branch of P.

Australia↗
PubMed2005

Multiple mutagenesis of P450 isoflavonoid synthase reveals a key active-site residue.

The leguminous isoflavonoid skeleton is constructed by P450 2-hydroxyisoflavanone synthase (CYP93C). Two active-site residues of CYP93C2, Ser 310 and Lys 375, are critical for unusual aryl migration of the flavanone substrate. Leu 371 is located near the substrate in a homology model, and mutant proteins regarding this residue were expressed in recombinant yeast microsomes. The single mutant, L371V, yielded only inactive P420, but multiple mutants incorporating K375T restored the P450 fold: the S310T-L371V-K375T triple mutant showed four times higher P450 level than the wild type. L371V-K375T and S310T-L371V-K375T produced a mixture of major 3beta-hydroxyflavanone and minor flavone, and 100% flavone, respectively, from a flavanone. Thus, Leu 371 appeared to control the substrate accommodation in favor of hydrogen abstraction from C-3 of the flavanone molecule and contribute to the P450 fold under the presence of Lys 375, the residue responsible for aryl migration. The molecular evolution of CYP93 enzymes is discussed.

Binding Sites↗
PubMed1990

Citrate substitutes for homocitrate in nitrogenase of a nifV mutant of Klebsiella pneumoniae.

An organic acid extracted from purified dinitrogenase isolated from a nifV mutant of Klebsiella pneumoniae has been identified as citric acid. H2 evolution by the citrate-containing dinitrogenase is partially inhibited by CO, and by some substrates for nitrogenase. The response of maximum velocities to changes in pH for both the wild-type and the NifV- dinitrogenase was compared. No substantial differences between the enzymes were observed, but there are minor differences. Both enzymes are stable in the pH range 4.8-10, but the enzyme activities dropped dramatically below pH 6.2.

Citrates↗
PubMed1977

Thyroid radiation dose during panoramic and cephalometric dental x-ray examinations.

Radiation exposure from panoramic equipment can be reduced significantly by use of smaller film, adjustment of the beam height to the height of the smaller film, and careful positioning of patients. These techniques have no adverse effect on the quality of the diagnostic information needed in dentistry. In addition to describing methods of reducing exposures from panoramic machines, this study demonstrates that the use of a barrier collar during static, cephalometric examinations can appreciably reduce thyroid exposure. Since the objective is to obtain diagnostic information from the film without irradiating the thyroid, the application of a lead-impregnated collar is a minor inconvenience, easily borne by the patient and operator. It should be noted that the use of the collar during panoramic examinations affords little or no protection since the relative motion of the panoramic machine places the axis of movement inside the head and neck of the patient. While the evolution of diagnostic radiology may have reached a high level of technical refinement of equipment and film the clinician still must avoid unnecessary exposure for X-ray examinations and must carefully select the best type of examination to be used for each patient. For example, a complete panoramic examination to determine the position of a known unerupted third molar tooth is probably not an exercise of good judgment since other examinations, such as periapical, could yield the same information with less exposure. Decisions must be made with good judgment, value being placed on relative risks versus the benefits of diagnostic yield.

Adolescent↗
PubMed2001

Review article: should we kill or should we save Helicobacter pylori?

Results from epidemiological studies and therapeutic clinical trials have shown that Helicobacter pylori infection causes acute and chronic active gastritis and is the initiating factor for the majority of peptic ulcer disease. Eradication of the infection with antibiotics resolves gastritis and restores normal gastric physiology, accelerates healing of peptic ulcer disease, and virtually eliminates recurrence of duodenal ulcer disease. The infection also plays an important role in the initiation and/or progression of gastric atrophy and intestinal metaplasia, which may eventually lead to the development of distal gastric cancer. Furthermore, almost all patients with gastric MALT lymphoma are infected with H. pylori and cure of the infection leads to histological regression of the tumor and maintains the regression in over 80% of patients during long-term follow-up. Preliminary uncontrolled data from Japan show that eradication of the infection significantly reduced metachronous intestinal-type gastric cancer following initial endoscopic resection of early gastric cancer and might also prevent the progression of gastric adenoma to gastric dysplasia or gastric cancer. Although this overwhelming evidence has demonstrated that H. pylori infection is bad for humans, some have questioned the wisdom of eradicating the infection in all those infected. Their arguments are largely based on hypothesis and circumstantial evidence: 1) Less than 20% of all H. pylori infected persons will develop significant clinical consequences in their lifetime. 2) H. pylori strains are highly diverse at a genetic level and are of different virulence. 3) The antiquity of H. pylori infection in humans and their co-evolution suggests that H. pylori may be a commensal to humans. Eradication of H. pylori may remove some beneficial bacterial strains and may provoke esophageal disease or gastric cancer at the cardia. However, careful review of the literature confirms that H. pylori infection is a serious pathogen albeit in a minority of those infected. It remains for carefully designed prospective studies, rather than hypothesis to make changes in the current consensus position.

Gastritis↗
PubMed2000

Morbidity assessment in urinary schistosomiasis infection through ultrasonography and measurement of eosinophil cationic protein (ECP) in urine.

In a Schistosoma haematobium-endemic village in western Madagascar we evaluated ultrasonography and Eosinophil Cationic Protein (ECP) in urine as means to detect the associated urinary tract pathology. 192 individuals were matched according to age and sex, and grouped into infected persons with bladder and, if present, kidney pathology (n = 96); infected persons without pathology (n = 48) and noninfected persons without pathology (n = 48). The median urinary egg count was significantly higher in individuals with ultrasonographically detectable urinary tract pathology (115 eggs/10 ml urine) than in infected persons without (45 eggs/10 ml of urine). At 136 ng/ml, the median ECP level was significantly higher in the 144 infected individuals than in the 48 noninfected persons (0.35 ng/ml). Egg excretion correlated positively with ECP level. The median ECP level was significantly higher in the group with ultrasonographically detectable urinary tract pathology than in the group without (183 ng/ml vs. 67 ng/ml). The results suggest that minor degrees of pathology, particularly at an early stage of infection with S. haematobium, might be overlooked by ultrasonography despite the presence of marked inflammation, as indicated by markedly increased urinary ECP levels in infected individuals without ultrasonographically detectable urinary tract pathology. ECP may therefore provide important information on the evolution of S. haematobium-associated urinary tract morbidity.

Adolescent↗