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Background: Diode-assisted endodontics is nowadays utilized for pulp space disinfection, but little is known on the bonding potential of this lased root dentin when the tooth is restored with an intracanal polymer post. Objectives: to investigate the influence of diode laser irradiation settings, in laser-assisted endodontics, on the intraradicular bonding of composite materials. Methods: Sixteen two-rooted, maxillary first premolars were collected, prepared up to F4 (Protaper Universal. DentsplyMaillefer, Ballaigues, Switzerland), and randomly assigned in two groups: group A (chopped mode or short pulse), diode irradiated according to protocol, pulse 25 ms, power 2.5 W, and group B (microchopped mode or ultrashort pulse), pulse 25 µs, peak power 12 W (both groups GentleRay. KaVo Dental, Biberach an der Riss, Germany). Buccal canals were irradiated, palatal ones served as controls. Canals were then obturated, post space was created in all canals, and quartz-fiber posts (ICE light Danville. Danville Materials, San Ramon, CA, USA) were cemented by self-etch self-curing cement (Max Cem Elite. Kerr, West Collins Orange, CA, USA) (Max Cem Elite. Kerr, Brea, CA, USA). A week later, teeth were sectioned horizontally in 1 mm increments. Push-out test was conducted in a Zwick testing machine (Zwick Roell, Ulm, Germany) at 1 mm/min speed, and the force required to dislodge the post from each specimen (F-max) was recorded. Weibull regression models were applied for statistical analyses. Results: Differences in F-max by group (control vs. chopped mode vs. microchopped mode) and height (meaning the apical-to-coronal position of each specimen along the root) were statistically significant (p < 0.05 in all cases). Conclusions: Short pulses (or chopped mode) had a profound positive effect on the quality of intraradicular bonding, while Ultrashort pulses (or microchopped mode) affected it negatively. In addition, apically positioned bonding proved weaker compared with more coronally located specimens. © 2022 by the authors. Licensee MDPI, Basel, Switzerland.

The Nconga Formation of the Mesoarchean (~2.96-2.84 Ga) Mozaan Group of the Pongola Supergroup of southern Africa contains the world’s oldest known granular iron formation. Three dimensional reconstructions of the granules using micro-focus X-ray computed tomography reveal that these granules are microstromatolites coated by magnetite and calcite, and can therefore be classified as oncoids. The reconstructions also show damage to the granule coatings caused by sedimentary transport during formation of the granules and eventual deposition as density currents. The detailed, three dimensional morphology of the granules in conjunction with previously published geochemical and isotope data indicate a biogenic origin for iron precipitation around chert granules on the shallow shelf of one of the oldest supracratonic environments on Earth almost three billion years ago. It broadens our understanding of biologically-mediated iron precipitation during the Archean by illustrating that it took place on the shallow marine shelf coevally with deeper water, below-wave base iron precipitation in micritic iron formations.

Background Intravenous thrombolysis (IVT) plays a prominent role in the treatment of acute ischemic stroke (AIS). The sooner IVT is administered, the higher the odds of a good outcome. Therefore, registering the in-hospital time to treatment with IVT, i.e. the door-to-needle time (DNT), is a powerful way to measure quality improvement. The aim of this study was to identify determinants that are associated with extended DNT. Methods Patients receiving IVT in 2015 and 2016 registered in the Dutch Acute Stroke Audit were included. DNT and onset-to-door time (ODT) were dichotomized using the median (i.e. extended DNT) and the 90th percentile (i.e. severely extended DNT). Logistic regression was performed to identify determinants associated with (severely) extended DNT/ODT and its effect on in-hospital mortality. A linear model with natural spline was used to investigate the association between ODT and DNT. Results Included were 9518 IVT treated patients from 75 hospitals. Median DNT was 26 min (IQR 20–37). Determinants associated with a higher likelihood of extended DNT were female sex (OR 1.17, 95% CI 1.05–1.31) and admission during off-hours (OR 1.12, 95% CI 1.01–1.25). Short ODT correlated with longer DNT, whereas longer ODT correlated with shorter DNT. Young age (OR 1.38, 95% CI 1.07–1.76) and admission to a comprehensive stroke center (OR 1.26, 1.10–1.45) were associated with severely extended DNT, which was associated with in-hospital mortality (OR 1.54, 95%CI 1.19–1.98). Conclusions Even though DNT in the Netherlands is short compared to other countries, lowering the DNT may be achievable by focusing on specific subgroups.

The oldest known granular iron formation (GIF) occurs in the ca. 2.96¬–2.92 Ga Mozaan Group of the Pongola Supergroup of southern Africa. The GIF comprises stacked beds interbedded with deeper water facies iron formation. The chert granules are marked by irregular rims composed of magnetite and calcite and can be defined as oncoids. Initial geochemical studies showed that the calcite is isotopically light, suggesting an organic carbon source for CO2, and that the Fe isotope characteristics of shallower water GIF are decoupled from those in the deeper water iron formation. Due to the complexity of the oncoidal rim morphologies, traditional petrography is complicated by the bias inherent to 2D intersections of the samples. However, the different mineral densities allow successful µXCT application revealing that rim morphologies are fairly homogenous consisting of multiple, multi-directional, micro-scale chert, magnetite and calcite domes surrounding the granule cores. The chert cores of the granules and domes suggest continuous chert precipitation in a wave-reworked environment. A surprising result was that calcite was not limited to the granule rims, and that some granules contain abundant calcite in their cores, indicating that calcite formation is not linked to that of magnetite. Ferric iron can therefore not be the organic carbon oxidant. 3D reconstruction of granules and samples shows that the GIF contains multiple upward fining beds, with granules decreasing in size, followed by granule and rim fragments, terminating in an Fe-rich clay layer. Granule rims can also be seen to have been broken off. These characteristics support deposition from storm surge currents.

Objective: The aim of this article was to investigate the temperature increase of the external root surface during laser-assisted endodontic treatment using a diode laser (980 nm) in a microchopped mode. Methods: Ten freshly extracted, human maxillary incisors with mature apices were collected, prepared to size F4 at working length (ProTaper; Dentsply Maillefer, Ballaigues, Switzerland), mounted to a holder, and irradiated (using spiral movements in coronal direction) with a diode laser (GENTLEray 980 Classic Plus; KaVo, Biberach, Germany) with a 200 μm fiber in four different treatment groups: Group 1 (control group) was irradiated in six cycles of 5-sec irradiation/20-sec pause with 2.5 W in the pulse mode. Groups 2 to 4 were irradiated at six cycles of 5-sec irradiation/20-sec pause in the microchopped mode (Group 2 - 1.6 W; Group 3 - 2.0 W; Group 4 - 2.5 W). The applied mode was 25 ms on/25 ms off. Within the on period, the laser delivered an intermittent sequence of energy complexes and the maximum output was equal to the nominated output of the device (12 W). Canals were kept moist by sterile saline irrigation in between irradiations, and temperature changes were continuously measured using a thermal imaging camera. Recordings were analyzed by a mixed model (analysis of variance [ANOVA] for repeated measurements). Results: The highest mean of temperature rise, 1.94°C ± 1.07°C, was measured in Group 4, followed by Group 3 (1.74°C ± 1.22°C) and Group 2 (1.58°C ± 1.18°C). The lowest increase occurred in Group 1 (1.06°C ± 1.20°C). There was a significant difference (p = 0.041) between the groups. Significant differences were found between Groups 1 and 4 (p = 0.007) and 1 and 2 (p = 0.035). In addition, a marginally significant difference between Groups 1 and 2 (p = 0.052) was noted. There was no significant difference between Groups 2, 3, and 4. Despite the low mean values reported, the highest temperature increase (+5.7°C) was measured in one of the specimens of treatment Group 2 at the middle third. Conclusions: Under the conditions used and within the limitations of the study, the microchopped diode laser irradiation is a safe possible treatment option in laser-assisted endodontic treatment, concerning the temperature elevation on the external root surface. © 2017, Mary Ann Liebert, Inc.

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International audience; SK 27 represents apartially crushed juvenile cranium that was found in 1949,in the Hanging Remnant of the Member 1of Swartkrans. Biochronologyand U-Pb isotopic datingof its provenance stratigraphic unit coincide toan age of c. 1.8 Ma. The specimen preserves theLI2, Ldm2, LM1, and RM1, the unerupted LP4 and LM2, small crown and root fragments representing the I1s, the RC and the Rdm2, as well as the isolated LC and LP3.Formerly attributed to Paranthropus robustus, SK 27 is now considered as morelikely representing early Homo, usually classified as H. habilis, but recently attributedto a possibly distinctsouthern African endemic taxon, H. gautengensis. In order to noninvasively extract from this problematic specimen additional morphostructural information suitable for clarifying its taxonomic status and phylogenetic relationships, the specimenSK 27 wasimaged by X-ray microtomographyand compared with similarevidence fromIndonesian H. erectus, North African H. heidelbergensis, as well as with Au. africanusand P. robustusrepresentatives from the South African hypodigm. Besides the virtual exploration and GM analysis of the premolar and molar enamel-dentine junction, we primarily focused on molar crown tissue proportions and enamel thickness distribution pattern. Our 3D analyses of the internal tooth crown structural organization of SK 27substantially differsfrom the average P. robustuscondition, butshow acombination of primitive (australopithecine-like) and derived (Homo-like) features.The taxonomic status of this controversialspecimen remains contentious,pointingto theneed for complementary analyses extendedto additional taxa, including Au. sediba.

IF 15.064 Fait partie du "Poster session 5: Are we better at managing cardiovascular disease in the elderly?" http://congress365.escardio.org/Presentation/139122#.WIsurH3sbBz; International audience

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(Atlanta, 12-16/4/2016). American Journal of Physical Anthropology 159, suppl. S62: 111 (résumé); International audience

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Changes in lifestyles and body weight affected mammal life-history evolution but little is known about how they shaped species' sensory systems. Since auditory sensitivity impacts communication tasks and environmental acoustic awareness, it may have represented a deciding factor during mammal evolution, including apes. Here, we statistically measure the influence of phylogeny and allometry on the variation of five cochlear morphological features associated with hearing capacities across 22 living and 5 fossil catarrhine species. We find high phylogenetic signals for absolute and relative cochlear length only. Comparisons between fossil cochleae and reconstructed ape ancestral morphotypes show that Australopithecus absolute and relative cochlear lengths are explicable by phylogeny and concordant with the hypothetized ((Pan,Homo),Gorilla) and (Pan,Homo) most recent common ancestors. Conversely, deviations of the Paranthropus oval window area from these most recent common ancestors are not explicable by phylogeny and body weight alone, but suggest instead rapid evolutionary changes (directional selection) of its hearing organ. Premodern (Homo erectus) and modern human cochleae set apart from living non-human catarrhines and australopiths. They show cochlear relative lengths and oval window areas larger than expected for their body mass, two features corresponding to increased low-frequency sensitivity more recent than 2 million years ago. The uniqueness of the "hypertrophied" cochlea in the genus Homo (as opposed to the australopiths) and the significantly high phylogenetic signal of this organ among apes indicate its usefulness to identify homologies and monophyletic groups in the hominid fossil record., SCOPUS: ar.j, info:eu-repo/semantics/published

Objective: The purpose of this study was to investigate the influence of bioglass, Nd:YAG laser irradiation and their combination on dentinal tubuli occlusion as a potential dentinal hypersensitivity treatment for cervical dentinal hypersensitivity (CDH). Background data: CDH affects 8-30% of adults and nearly 85% of perio-treated patients. Various treatment schemes have been applied for treating CDH, among them being fluoride application, laser irradiation, and, recently, bioglass (NovaMin®). In this in vitro study, we evaluated the efficacy of NovaMin® paste (NM) (Denshield, Sultan, USA), Nd:YAG laser irradiation (L) at various power settings, and their combination, on dentinal orifice occlusion (DOO) as potential treatments for CDH. Methods: Forty-nine human dentin surfaces were organized into seven equal groups: groups A and B received NM followed by L (0.5 and 1 W, respectively); groups C and D received L (0.5 and 1 W, respectively) followed by NM; group E received NM; and groups F and G received L (0.5 and 1 W, respectively). Specimens were evaluated with regard to DOO under environmental scanning electron microscope. Results: Treatment modality significantly affected DOO (p=0.012). Groups B and G scored higher DOO than the rest. By ordinal logistic regression (with boostrap standard errors), the combination of NM followed by 1 W Nd:YAG laser irradiation (group B) significantly (p

Introduction: This in vitro study evaluated the efficacy of bioglass (Denshield; Novamin Technology, Alachua, FL) and Neodymium-doped yttrium-aluminum-garnet (Nd:YAG) laser irradiation on dentinal tubuli orifice occlusion (DOO) by comparing samples examined under environmental scanning electron microscope (ESEM) after applying each desensitizing approach separately and in combination. Methods: Forty-eight human molars were collected, randomly organized in 4 equal groups, and had their cervical dentin exposed. Additionally, in half of the specimens of each experimental group, the smear layer was removed (subgroups A1, B1, C1, and D1). Group A received NovaMin paste treatment for 5 minutes (NM) to the experimental surface. Group B received Nd:YAG laser irradiation (0.5 w, 10 Hz, and 50 mJ) (L). Group C received NM followed by L. Group D was treated with L followed by NM. All specimens were stored for 24 hours and evaluated for DOO under ESEM by 4 blinded observers. Results: The presence of a smear layer significantly contributed to DOO regardless of the treatment modality (ordinal logistic regression, P

Concerns about public health risks of intensive animal production in the Netherlands continue to rise, in particular related to outbreaks of infectious diseases. The aim was to investigate associations between the presence of farm animals around the home address and Q fever and pneumonia.Electronic medical record data for the year 2009 of all patients of 27 general practitioners (GPs) in a region with a high density of animal farms were used. Density of farm animals around the home address was calculated using a Geographic Information System. During the study period, a large Q fever outbreak occurred in this region. Associations between farm exposure variables and pneumonia or 'other infectious disease', the diagnosis code used by GPs for registration of Q fever, were analyzed in 22,406 children (0-17 y) and 70,142 adults (18-70 y), and adjusted for age and sex. In adults, clear exposure-response relationships between the number of goats within 5 km of the home address and pneumonia and 'other infectious disease' were observed. The association with 'other infectious disease' was particularly strong, with an OR [95%CI] of 12.03 [8.79-16.46] for the fourth quartile (>17,190 goats) compared with the first quartile (

Contains fulltext : 88112.pdf (Publisher’s version ) (Closed access) BACKGROUND: Stents are an alternative treatment to carotid endarterectomy for symptomatic carotid stenosis, but previous trials have not established equivalent safety and efficacy. We compared the safety of carotid artery stenting with that of carotid endarterectomy. METHODS: The International Carotid Stenting Study (ICSS) is a multicentre, international, randomised controlled trial with blinded adjudication of outcomes. Patients with recently symptomatic carotid artery stenosis were randomly assigned in a 1:1 ratio to receive carotid artery stenting or carotid endarterectomy. Randomisation was by telephone call or fax to a central computerised service and was stratified by centre with minimisation for sex, age, contralateral occlusion, and side of the randomised artery. Patients and investigators were not masked to treatment assignment. Patients were followed up by independent clinicians not directly involved in delivering the randomised treatment. The primary outcome measure of the trial is the 3-year rate of fatal or disabling stroke in any territory, which has not been analysed yet. The main outcome measure for the interim safety analysis was the 120-day rate of stroke, death, or procedural myocardial infarction. Analysis was by intention to treat (ITT). This study is registered, number ISRCTN25337470. FINDINGS: The trial enrolled 1713 patients (stenting group, n=855; endarterectomy group, n=858). Two patients in the stenting group and one in the endarterectomy group withdrew immediately after randomisation, and were not included in the ITT analysis. Between randomisation and 120 days, there were 34 (Kaplan-Meier estimate 4.0%) events of disabling stroke or death in the stenting group compared with 27 (3.2%) events in the endarterectomy group (hazard ratio [HR] 1.28, 95% CI 0.77-2.11). The incidence of stroke, death, or procedural myocardial infarction was 8.5% in the stenting group compared with 5.2% in the endarterectomy group (72 vs 44 events; HR 1.69, 1.16-2.45, p=0.006). Risks of any stroke (65 vs 35 events; HR 1.92, 1.27-2.89) and all-cause death (19 vs seven events; HR 2.76, 1.16-6.56) were higher in the stenting group than in the endarterectomy group. Three procedural myocardial infarctions were recorded in the stenting group, all of which were fatal, compared with four, all non-fatal, in the endarterectomy group. There was one event of cranial nerve palsy in the stenting group compared with 45 in the endarterectomy group. There were also fewer haematomas of any severity in the stenting group than in the endarterectomy group (31 vs 50 events; p=0.0197). INTERPRETATION: Completion of long-term follow-up is needed to establish the efficacy of carotid artery stenting compared with endarterectomy. In the meantime, carotid endarterectomy should remain the treatment of choice for patients suitable for surgery. FUNDING: Medical Research Council, the Stroke Association, Sanofi-Synthelabo, European Union.

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Lipoprotein lipase (LPL) is bound to heparan sulphate proteoglycans (HSPG) at the luminal surface of endothelium. It is the key enzyme involved in the hydrolysis of very low density lipoproteins (VLDL). Prior to lipolysis by LPL, the lipoproteins are considered to interact with vessel wall HSPG. Apolipoprotein (apo) E is thought to mediate this interaction thereby enhancing the stability of the lipoprotein-LPL complex. We hypothesize that apo E mutations may cause a diminished interaction of VLDL with HSPG leading to impaired lipolysis of VLDL by HSPG-bound LPL. In order to test this hypothesis, lipolysis experiments were performed using HSPG-bound LPL. The mean lipolysis rates of VLDL, isolated from the apo E2 (Lys146 → Gln) heterozygotes, apo E2 (Arg158 → Cys) homozygotes and apo E3-Leiden heterozygotes were 92.3 ± 10.3 (ns), 77.3 ± 4.2 (P < 0.05) and 76.7 ± 10.0% (P < 0.05), respectively, of that of control VLDL (100.0 ± 9.7%). No differences in lipolysis were observed between VLDL from controls and VLDL from the same patients if LPL in solution was used. Thus, compositional differences alone can not explain the differences in lipolysis rates observed with HSPG-bound LPL. In competition experiments, the binding efficiency to HSPG-LPL of VLDL from the apo E2 (Lys146 → Gln) heterozygotes, apo E2 (Arg158 → Cys) homozygotes and apo E3-Leiden heterozygotes was 63 (ns), 41 (P< 0.05) and 35% (P < 0.05), respectively of that of control VLDL (100%). We conclude that VLDL isolated from apo E2 homozygotes and apo E3-Leiden heterozygotes display decreased lipolysis by HSPG-bound LPL due to a defective binding of these lipoproteins to the HSPG-LPL complex.

Concerns about public health risks of intensive animal production in the Netherlands continue to rise, in particular related to outbreaks of infectious diseases. The aim was to investigate associations between the presence of farm animals around the home address and Q fever and pneumonia. Electronic medical record data for the year 2009 of all patients of 27 general practitioners (GPs) in a region with a high density of animal farms were used. Density of farm animals around the home address was calculated using a Geographic Information System. During the study period, a large Q fever outbreak occurred in this region. Associations between farm exposure variables and pneumonia or ‘other infectious disease’, the diagnosis code used by GPs for registration of Q fever, were analyzed in 22,406 children (0–17 y) and 70,142 adults (18–70 y), and adjusted for age and sex. In adults, clear exposure-response relationships between the number of goats within 5 km of the home address and pneumonia and ‘other infectious disease’ were observed. The association with ‘other infectious disease’ was particularly strong, with an OR [95%CI] of 12.03 [8.79–16.46] for the fourth quartile (>17,190 goats) compared with the first quartile (

The association of human C-reactive protein (CRP) with nonstimulated and PMA-stimulated human neutrophils and the concomitant degradation of CRP (monitored by TCA-soluble peptides and SDS-PAGE analysis) has been studied. Maximum association of 125I-labeled CRP with neutrophils and 125I-labeled CRP degradation during association with these cells was achieved by stimulating the neutrophils with PMA at 10 ng/ml; a concentration in which azurophil granule release was not significant. For PMA-stimulated neutrophils, the association of 125I-labeled CRP was 1.8 times higher and PMA-stimulated neutrophil-mediated degradation of the ligand was three times faster than that for nonstimulated cells. The neutrophil-associated 125I-labeled CRP in the absence and presence of PMA proved on SDS-PAGE analysis to be approximately 50% degraded. There was a positive correlation between the extent of CRP degradation and the association of 125I-labeled CRP with neutrophils. In addition to generation of neutrophil associated CRP intermediates, small soluble CRP peptides were generated during association of CRP with neutrophils. These peptides inhibited superoxide production from opsonized zymosan-activated neutrophils by approximately 40% at 10 micrograms/ml. 125I-labeled CRP degradation mediated by nonstimulated neutrophils, and neutrophil-conditioned medium (from both non-stimulated and PMA-stimulated cells) was inhibitable by alpha 1-antitrypsin and approximately seven times less at 1 h than that occurring during 125I-labeled CRP-association with PMA-stimulated neutrophils. The degradation of 125I-labeled CRP mediated by PMA-stimulated neutrophils was not fully inhibitable by alpha 1-antitrypsin. The data point to the involvement of a membrane-associated serine protease, which is maximally activated by PMA, in the degradation of 125I-labeled CRP during association with neutrophils. Our results indicate that at an inflammatory site CRP-derived peptides can be produced that inhibit the action of activated neutrophils.

C-reactive protein (RP) and serum amyloid P component (SAP) have been identified for the first time in rat serum and isolated by calcium-dependent affinity chromatography. Rat CRP closely resembled human CRP in its amino acid composition, in having five subunits per molecule and in its electron microscopic appearance as a pentameric annular disc. It differed, however, from all other mammalian CRP's characterised hitherto in being a glycoprotein bearing a single complex oligosaccharide on each polypeptide subunit. Furthermore one pair of tis subunits per molecule was linked by a interchain disulphide bridges whereas in other animals the subunits of both CRP and SAP are all non-covalently associated. The serum concentration of CRP in normal healthy laboratory rats and in specific pathogen-free rats was 300-600 micrograms/ml which is much greater than has been described in any other species and exceeds even maximal acute phase levels of CRP in man. Following injections of casein or croton oil, serum CRP levels rose to a maximum of about 900 micrograms/ml. Rat CRP bound to pneumococcal C-polysaccharide (CPS( but, in marked contrast to the behaviour of CRP from man, rabbit and marine teleost fish, it did not precipitate with CPS solutions, agglutinate CPS-coated sheep erythrocytes or initiate complement activation. Rat SAP, like SAP of other species, was a glycoprotein but unlike them it was composed only of a single pentameric disc not two such discs interacting face-to-face. The normal level of SAP in rat serum was 20-50 micrograms/ml, very similar to the levels seen in man, and it did not behave as an acute phase reactant in response to casein or croton-oil injections. In this respect it resembled human SAP but differed from murine SAP which is a major acute phase reactant.

Two distinct pentraxin proteins were isolated from bovine serum by calcium-dependent affinity chromatography on high pyruvate agarose gel. One of these proteins cross-reacted specifically with certain rabbit anti-human CRP antisera and was therefore designated as bovine CRP. The other cross-reacted specifically with a sheep anti-human SAP antiserum and was therefore designated as bovine SAP. Although the mixture of these two pentraxins was not resolved by gel filtration chromatography, they were separated by solid phase absorption of the CRP with immobilized rabbit anti-human CRP antibodies. Their identity as pentraxins was confirmed by their electron microscopic appearance. Bovine CRP was composed of a single type of non-glycosylated subunit whilst bovine SAP contained two major types of glycosylated subunits and a minor polypeptide, the glycosylation of which was not determined. Serum concentrations were in the range of 5-40 mg/l and neither protein behaved as an acute phase reactant. No bovine serum protein undergoing calcium-dependent binding to phosphoryl choline or pneumococcal C-polysaccharide was obtained.

Serum amyloid P-component (protein SAP) was found to bind in vitro to isolated amyloid fibrils of both primary and secondary types. The binding was strictly calcium-dependent, optimal uptake requiring at least 0.5 mM calcium ion. Using normal human serum as the source of protein SAP different fibril preparations became saturated with between 5--20 micrograms of SAP per mg dry weight of fibril. Isolated pure protein SAP bound in greater amounts. In control experiments SAP did not bind significantly to collagen fibrils, sheep erythrocytes, plastic shavings, or the following immobilized proteins: human kappa or lambda Bence-Jones proteins; human; rabbit or mouse IgG; human serum albumin. C-reactive protein, which resembles protein SAP structurally but has calcium-dependent specificity for different ligands, bound significantly to only one of five different amyloid fibril preparations.

Skin biopsies from patients with leprosy across the spectrum from tuberculoid (TT) to lepromatous (LL), including histoid lepromas and erythema nodosum leprosum (ENL) reactions, were stained immunohistochemically for the presence of C-reactive protein (CRP) and the apolipoprotein, apoB. Mycobacterium leprae bacillary material comprising cell walls, cytoplasmic and soluble components was present with increasing abundance towards the lepromatous end of the spectrum and always stained positively with anti-CRP. M. leprae from armadillos did not stain with anti-human CRP indicating that the staining of M. leprae in human tissues was not due to a cross-reaction between anti-CRP and the organism itself. When CRP was present in large amounts apoB was also demonstrated in the same distribution. CRP was detected on bacilli and their degradation products within the cytoplasm of macrophages even in the absence of a raised serum CRP level in some ENL patients and also in two cases of advanced resolving lepromas. These findings demonstrate remarkable persistence of CRP in association with M. leprae in vivo, and raise intriguing questions about the possible role of CRP in relation to the handling of leprosy bacilli.