bluuebunny/crossref_metadata_2025 huggingface dataset:
Accessibility of selected hospitals and medical procedures by means of aerial and transit network-based measures
Authors: Costa L. S. , Nassi C. D. , Pinheiro R. S. , Almeida R. M. V. R.
Published: May 2003

Objective: This report investigates the use of linear and travelled route (transit network-based) distances in estimating the accessibility of hospitals to patients, for some selected hospital admission diagnostics.

Methods: For patients admitted to 14 public hospitals in Rio de Janeiro City, during 1996, under the ICD-9 headings 'Complications of Pregnancy, Childbirth and the Puerperium' and 'Disorders of the Circulatory System', average distances between the patient's district of residence and hospital of admission were calculated (both as Euclidean and as network-based distances). Data were obtained from the country's public health data processing agency. Geographic co-ordinates were obtained for districts of residence from the postal codes of the patients' residences. Distances were estimated with the TransCAD Geographical Information System, based on a map of the city transit network. There were 8654 patients admitted under the 'Complications of Pregnancy' heading and 3439 under 'Disorders of Circulatory System'.

Results: Variations of up to a factor of 5.3, and up to 34 km, could be identified between linear and network estimates.

Conclusion: While recognizing that network estimates have advantages, the literature on accessibility frequently argues that aerial estimates are a good approximation for those. The present results show that this is not necessarily the case.
Detection of chimerism following vascularized bone allotransplantation by polymerase chain reaction using a Y‐chromosome specific primer
Authors: Muramatsu Keiichi , Valenzuela Richard G. , Bishop Allen T.
Published: June 2003

Chimerism following allogeneic organ transplantation is a phenomenon known to occur and be associated with development of immunologic tolerance in allotransplantation. However, little is known about graft cell migration following vascularized bone allografting. In this study, chimerism was assessed following vascularized tibia transplantation from male DA or PVG donors to female PVG rat recipients using a semi‐quantitative polymerase chain reaction for the Y‐chromosome. FK‐506 (Tacrolimus) was administered after transplantation for immunosuppression. All immunosuppresssed PVG rat recipients of PVG bone grafts showed a high level of chimerism (1%) in the thymus, spleen, liver and cervical lymph nodes at 18 weeks post‐transplant. Donor cells were also detected in the contralateral tibia and humerus. In non‐immunosuppressed PVG rat recipients of DA bone grafts, donor cells were detected in the spleen in three of five rats within 2 weeks post‐transplant. In these animals the bone grafts were severely rejected. In immunosuppressed PVG rat recipients of DA bone grafts, two of five, four of eight and eight of 10 rats showed low level chimerism (0.1%) in peripheral blood at 1, 12, and 18 weeks post‐transplant. Six rats showed a high level of chimerism in the spleen and thymus. Histological studies revealed no rejection findings through 18 weeks post‐transplant. Our results indicate that chimerism, or the presence of graft cells in host tissue, may occur in the face of acute rejection and be demonstrable following vascularized isograft and allograft living bone transplantation when chronic immunosuppression is maintained. Graft vascular patency during the short‐term likely allows cellular migration, even in the face of acute rejection. Long‐term survival and proliferation of graft marrow elements in host tissue may be possible with adequate immunosuppression. © 2003 Orthopaedic Research Society. Published by Elsevier Science Ltd. All rights reserved.
Reversion From Precore/Core Promoter Mutants to Wild–Type Hepatitis B Virus During the Course of Lamivudine Therapy
Authors: Cho Sung Won , Hahm Ki-Baik , Kim Jin Hong
Published: June 2003

The effect of lamivudine administration on the evolution of precore/core promoter mutation is unknown. The aim of this study was to determine the changes of precore/core promoter sequences in chronic type B hepatitis patients treated with lamivudine. Serial sera were obtained from 11 patients before, at the beginning of, and during therapy. Serum samples were polymerase chain reaction–amplified, and nucleotide sequences of hepatitis B virus (HBV) were analyzed. At baseline, precore and core promoter mutations were found in 6 and 4 of 11 patients, respectively. A precore stop codon mutant was replaced by a wild–type virus in all 6 patients infected with precore mutant at a median treatment of 12 months (vs. before therapy;P= .011). Mutations in the core promoter appeared in only 1 of 10 patients (vs. before therapy;P= .021). However, precore and core promoter mutations appeared in 5 and 7 of 10 patients at a median treatment of 21 months, respectively. Acute exacerbation occurred after lamivudine withdrawal in 2 patients who had hepatitis B e antigen (HBeAg) loss or seroconversion. The serum remained HBeAg–negative throughout the study period, and each of 2 patients had precore wild–type virus during acute exacerbation. HBV mutants with core gene deletions are not eliminated completely during prolonged therapy in 2 patients in whom the HBV genomes had core gene deletions at baseline. In conclusion, lamivudine therapy resulted in reversion from precore/core promoter mutants to wild–type. However, mutations in the precore and core promoter region reappeared during prolonged therapy. HBeAg–negative wild–type precore hepatitis B virus could be selected after lamivudine withdrawal in patients who had HBeAg loss or seroconversion.
Characterization of Transmission of
Pneumocystis carinii
f. sp.
muris
through Immunocompetent BALB/c Mice
Authors: Gigliotti F. , Harmsen A. G. , Wright T. W.
Published: June 2003

By using mouse models, it has been shown that
Pneumocystis carinii
f. sp.
muris
can be transmitted to immunocompetent mice that are exposed to immunosuppressed mice with active
P. carinii
pneumonia. We sought to determine whether
P. carinii
f. sp.
muris
could be transmitted between normal mice. The rationale for these experiments was to demonstrate whether the normal host could serve as the reservoir of organisms that produce Pcp when the organism is acquired by the immunosuppressed host. Under the conditions of these experiments, normal mice are able to be infected by brief cohousing with
P. carinii
-infected SCID mice. There was active replication of organisms in the normal host such that the organism could be transmitted to other normal mice, again with active replication. Mice that had seroconverted after exposure to
P. carinii
-infected SCID mice were more resistant to infection when reexposed. Infection in normal mice was well tolerated with minimal effects on dynamic lung compliance. We speculate, based on these results, that transmission from normal host to normal host, as an asymptomatic or minimally symptomatic infection, could be a way to maintain this opportunistic pathogen in the environment.
Macrophage-Mediated Germination of
Bacillus anthracis
Endospores Requires the
gerH
Operon
Authors: Weiner Matthew A. , Hanna Philip C.
Published: June 2003

The

gerH
abc

operon of
Bacillus anthracis
, encoding a
gerA
-like family member of germinant sensors, was shown to be required for endospore germination in the presence of macrophages and in macrophage-conditioned media. The loss of the germination phenotype in macrophage cultures of
B. anthracis gerH
-null endospores was restored by complementation in
trans
with a wild-type copy of
gerH
expressed under the control of its own promoter. Using endospores from both the parental strain
B. anthracis
Sterne and an isogenic
gerH
-null strain, we partially characterized germinants secreted by macrophages into the extracellular medium.
Reliability and Validity of the Niddk–Qa Instrument in the Assessment of Quality of Life in Ambulatory Patients With Cholestatic Liver Disease
Authors: Kim Ray W. , Lindor Keith D. , Malinchoc Michael , Petz Jan L. , Jorgensen Roberta , Dickson Rolland E.
Published: June 2003

The NIDDK–QA instrument, developed and widely used in liver transplant recipients, assesses quality of life (QOL) in four domains, including liver disease symptoms, physical function, health satisfaction, and overall well–being. We investigated whether the instrument may be used as a disease–specific instrument in ambulatory patients with cholestatic liver disease. The NIDDK–QA instrument was administered in 96 patients with primary biliary cirrhosis (PBC) and primary sclerosing cholangitis (PSC) seen at the Mayo Clinic. The SF–36, a well–established generic instrument, was also administered. Standard measures for test–retest reliability, internal consistency, and discriminant and concurrent validity were examined. All patients were ambulatory with mostly normal levels of serum bilirubin and albumin concentrations. The reliability of the NIDDK–QA, as measured by test–retest correlation (Pearson coefficients: 0.82–0.99, P < .01) and by internal consistency (Cronbach's alpha: 0.87–0.94) exceeded conventional acceptability criteria. The correlation between domain scores of the NIDDK–QA and SF–36 was clear and logical in that the physical function domain of NIDDK–QA strongly correlated with the physical component summary score of SF–36 (r = 0.86, P < .01). The overall well–being domain of the NIDDK–QA was closely associated with the mental summary score of SF–36 (r = 0.69, P < .01). Among PBC patients, there was a modest yet significant correlation between the Mayo risk score and overall well–being (r = -0.26, P = .03). In the assessment of QOL in patients with cholestatic liver disease, NIDDK–QA is found reliable and valid. These data, combined with our previous study, demonstrate its applicability in a wide spectrum of disease severity, ranging from early, ambulatory–phase disease to decompensated cirrhosis necessitating liver transplantation.
Virologic and Clinical Expressions of Reciprocal Inhibitory Effect of Hepatitis B, C, and Delta Viruses in Patients With Chronic Hepatitis
Authors: Sagnelli Evangelista , Coppola Nicola , Scolastico Carlo , Filippini Pietro , Santantonio Teresa , Stroffolini Tommaso , Piccinino Felice
Published: June 2003

We studied 648 hepatitis B surface antigen (HBsAg)– and/or anti-hepatitis C virus (HCV)–positive patients to evaluate the virologic and clinical characteristics of multiple hepatitis viral infection. We defined as Case B–C an HBsAg/anti–HCV positive patient and as Case b–C an anti–HCV/anti–HBc–positive, HBsAg/anti–HBs-negative patient. For each Case B–C we scheduled as Control–B an HBsAg positive and anti–HCV negative patient and as Control–C an HBsAg/anti–HBs/anti-hepatitis B core antigen (HBc)–negative and anti–HCV-positive patient. Control group C was used as the control also for Case group b–C. Serum HBV DNA by molecular hybridization was found more frequently in Control group B (54% of 161 patients) than in Case group B–C (35.7% of 84, P < .01). The prevalence of HBV wild type was similar in Case group B–C (14.3%) and in Control group B (17.4%), whereas the e–minus strain was less frequent in Case group B–C (10.7% vs. 33%; P < .01). HBV DNA by polymerase chain reaction (PCR) was detected in 40.8% of 71 patients in Case group b–C. HCV RNA was detected more frequently in Control group C (90.7% of 130 patients) than in Case group B–C (65.2% of 69, P < .0001). Moderate or severe chronic hepatitis or cirrhosis were more frequent in Case group B–C (62.9% of 65 patients) than in Control group B (46.7% of 90, P < .05) or C (40.8% of 98, P < .005), and in Case group b–C (71.1% of 76) than in Control group C. Thus, in multiple hepatitis we observed a reciprocal inhibition of the viral genomes and a more severe liver disease. In Case group b–C, serum HBV DNA was frequent and the clinical presentation was severe.
Impact of Interferon Alfa–2B and Ribavirin on Progression of Liver Fibrosis in Patients With Chronic Hepatitis C
Authors: Poynard Thierry , McHutchison John , Davis Gary L. , Esteban-Mur Rafael , Goodman Zachary , Bedossa Pierre , Albrecht Janice
Published: June 2003

The extent of liver fibrosis is an important prognostic factor in patients infected with hepatitis C virus. Administration of a combination of interferon and ribavirin produces a superior viral clearance response rate than interferon alone. The effect of this combination regimen on hepatic fibrosis has not been established. To determine the impact of combination regimen or interferon alone on the progression of liver fibrosis we pooled individual data of 1,509 patients with pretreatment and post–treatment biopsies from 3 randomized trials. Fibrosis progression and regression rates between biopsies were calculated by the Kaplan–Meier method and by the fibrosis progression rate per year. The percentage of patients without significant fibrosis (stage 0 or 1) at 96 weeks was 68 ± 4% (mean ± SE) when treated by combination regimen for 48 weeks, 64 ± 4% by interferon alone for 48 weeks, 42 ± 7% by combination regimen for 24 weeks (lower than both 48–week regimens P < .001), and 24 ± 9% interferon alone for 24 weeks (lower than the combination regimen for 24 weeks; P = .02). Three factors were independently associated with fibrosis reduction: sustained viral response, duration of treatment, and baseline fibrosis stage (all P < .001 in proportional hazards regression model). These results show that interferon and ribavirin combination therapy significantly reduces the rate of fibrosis progression in patients with hepatitis C. This effect was most prominent in patients who achieved a virologic response, those receiving 48 weeks of therapy, and in patients with significant fibrosis at baseline.
HEp-2 Cell Adherence, Actin Aggregation, and Intimin Types of Attaching and Effacing
Escherichia coli
Strains Isolated from Healthy Infants in Germany and Australia
Authors: Beutin Lothar , Marchés Olivier , Bettelheim Karl A. , Gleier Kerstin , Zimmermann Sonja , Schmidt Herbert , Oswald Eric
Published: June 2003

Fecal samples from healthy children under 2 years of age living in Berlin, Germany (205 infants), and Melbourne, Australia (184 infants), were investigated for the presence of attaching and effacing (AE)
Escherichia coli
(AEEC) strains by screening for
eae
(intimin) genes. Twenty-seven AEEC strains were isolated from 14 children (7.6%) from Melbourne and from 12 children (5.9%) from Berlin. The 27 AEEC strains were classified as enterohemorrhagic
E. coli
(one strain, producing Shiga toxin 1), typical enteropathogenic
E. coli
(EPEC) (one strain carrying an EPEC adherence factor [EAF] plasmid), and atypical EPEC (25 strains negative for Shiga toxins and EAF plasmids). The AEEC were divided into 18 different serotypes, O-nontypeable and O-rough strains. Typing of their intimin genes revealed the presence of intimin α in 6 strains, intimin β in 11 strains, intimin γ in 7 strains, intimin ζ in 2 strains, and intimin η in one strain. Analysis of HEp-2 cell adherence showed diffuse adherence or localized adherence-like patterns in 26 AEEC strains; local adherence was found only with the EAF-positive strain. Ten AEEC strains showed an AE property with the fluorescent actin staining (FAS) test. The introduction of an EAF plasmid (pMAR7) converted 11 FAS-negative AEEC strains to FAS positive and increased the FAS reaction in six FAS-positive AEEC strains, indicating that the genes needed for the AE phenotype were functional in these strains. Our finding indicates that atypical EPEC strains could play a double role as strains that naturally immunize against intimin in humans and as reservoirs for new emerging human pathogenic EPEC strains.
Lack of Gender-Specific Antibody Recognition of Products from Domains of a
var
Gene Implicated in Pregnancy-Associated
Plasmodium falciparum
Malaria
Authors: Jensen Anja T. R. , Zornig Hanne D. , Buhmann Caecilie , Salanti Ali , Koram Kwadwo A. , Riley Eleanor M. , Theander Thor G. , Hviid Lars , Staalsoe Trine
Published: June 2003

Gender-specific and parity-dependent acquired antibody recognition is characteristic of variant surface antigens (VSA) expressed by chondroitin sulfate A (CSA)-adherent
Plasmodium falciparum
involved in pregnancy-associated malaria (PAM). However, antibody recognition of recombinant products of a specific VSA gene (
2O2var1
) implicated in PAM and transcribed by a CSA-adhering parasite line did not have these characteristics. Furthermore, we could not demonstrate preferential transcription of
2O2var1
in the CSA-adhering line versus the unselected, parental isolate. Our data call for circumspection regarding the molecular identity of the parasite ligand mediating adhesion to CSA in PAM.
The 35‐hour week in France: the French exception?
Authors: Alis David
Published: June 2003

The 1980s and 1990s were periods of far‐reaching transformations in working hours and flexibility in Europe. Usually those initiatives came from the social partners. Yet France stood out during this period in that it maintained an interventionist state; the climax of public intervention came when the Aubry laws were passed introducing the 35‐hour working week. Paradoxically, the Aubry laws resulted not in a weakening of collective bargaining, but in an unprecedented series of negotiations in companies. This article sets out the process leading to the laws, and then analyses the results of the negotiations.
Gingipain RgpB Is Excreted as a Proenzyme in the
vimA
-Defective Mutant
Porphyromonas gingivalis
FLL92
Authors: Olango G. Jon , Roy Francis , Sheets Shaun M. , Young Mary K. , Fletcher Hansel M.
Published: June 2003

We have previously shown that the unique
vimA
(virulence-modulating) gene could modulate proteolytic activity in
Porphyromomas gingivalis
. Although a reduction in cysteine protease activity was observed in the
vimA
-defective mutant,
P. gingivalis
FLL92, compared to that of the wild-type strain, no changes were seen in the expression of the gingipain genes. This result might suggest posttranscriptional regulation of protease expression. To determine whether there was a defect in the translation, transport, or maturation of the gingipains,
P. gingivalis
FLL92 was further characterized. In contrast to the wild-type strain, a 90% reduction was seen in both Rgp and Kgp protease activities in strain FLL92 during the exponential growth phase. These activities, however, increased to approximately 60% of that of the wild-type strain during stationary phase. Throughout all the growth phases, Rgp and Kgp activities were mostly soluble, in contrast to those of the wild-type strain. Western blot analyses identified unique Rgp- and Kgp-immunoreactive bands in extracellular protein fractions from FLL92 grown to late exponential phase. Also, the RgpB proenzyme was identified in this fraction by mass spectrometry. In addition, in vitro protease activity could be induced by a urea denaturation-renaturation cycle in this fraction. These results indicate that protease activity in
P. gingivalis
may be growth phase regulated, possibly by multiple mechanisms. Furthermore, the gingipain RgpB is excreted in an inactive form in the
vimA
mutant. In addition, these results provide the first evidence of posttranslational regulation of protease activity in
P. gingivalis
and may suggest an important role for the
vimA
gene in protease activation in this organism.
Combined Treatment with Interleukin-12 and Mebendazole Lessens the Severity of Experimental Eosinophilic Meningitis Caused byAngiostrongylus cantonensisin ICR Mice
Authors: Du Wen-Yuan , Liao Jiunn-Wang , Fan Chia-Kwung , Su Kua-Eyre
Published: June 2003

Angiostrongylus cantonensisis the major cause of eosinophilic meningoencephalitis cases in Taiwan. Mice were orally infected with 35 infective larvae. One group of mice were given a single dose of mebendazole (20 mg/kg of body weight) per os at various times and examined at 14 days postinfection (dpi) for worm recovery rate and pathological studies. A 94 to 97% reduction in worm recovery was observed when medication was given at 4 to 5 dpi. Sections of the brains revealed that untreated infected mice developed typical severe eosinophilic meningoencephalitis. Meninges of these mice were thickened by massive infiltration of eosinophils, whereas only moderate pathological change was observed in the brains of mice that were treated with mebendazole at 4 dpi. Infected mice that received daily injections of 10 ng of interleukin-12 (IL-12) only for various numbers of days also exhibited moderate pathological changes in the brain. Eosinophil infiltration in the brains of these mice was low, and severe mechanical injuries in the parenchyma were observed. Treatment with mebendazole in combination with IL-12, however, resulted in low levels of worm recovery and dramatic lessening of the eosinophilic meningitis. A reverse transcriptase PCR assay of mRNA expression in the brain also revealed that the use of IL-12 had shifted the immune response of the mouse from Th2 type to Th1 type. This study could be used in developing strategies for the treatment of human angiostrongylosis.
Cytotoxic Necrotizing Factor 1 Enhances Reactive Oxygen Species-Dependent Transcription and Secretion of Proinflammatory Cytokines in Human Uroepithelial Cells
Authors: Falzano Loredana , Quaranta Maria Giovanna , Travaglione Sara , Filippini Perla , Fabbri Alessia , Viora Marina , Donelli Gianfranco , Fiorentini Carla
Published: June 2003

Uropathogenic
Escherichia coli
strains frequently produce a Rho-activating protein toxin named cytotoxic necrotizing factor type 1 (CNF1). We herein report that CNF1 promotes transcription and release of tumor necrosis factor alpha, gamma interferon, interleukin-6 (IL-6), and IL-8 proinflammatory cytokines and increases the production of reactive oxygen species (ROS) in uroepithelial T24 cells. The antioxidant
N
-acetyl-
l
-cysteine counteracts these phenomena, a fact which suggests a role for ROS-mediated signaling in CNF1-induced proinflammatory cytokine production.
Congenital Duplication of the Palm in a Patient with Multiple Anomalies
Authors: AL-QATTAN M. M.
Published: June 2003

In 1995, Parr and McMahon described a syndrome of congenital duplication of footpads in mice which lacked a protein called ‘Wingless-type mouse mammary tumour virus integration site family member 7a” (Wnt-7a). This syndrome has not been described in humans and the following report describes a similar syndrome in a Saudi girl. The role of Wnt-7a in the development of the limb along the dorso-ventral axis is discussed, along with interaction between the Wnt-7a and other axes of limb growth.
Excision of the Trapezium and Interposition Arthroplasty with Gelfoam for the Treatment of Trapeziometacarpal Osteoarthritis
Authors: NUSEM I. , GOODWIN D. R.
Published: June 2003

Excision of the trapezium with Gelfoam interposition was performed in 35 thumbs, 34 of which were evaluated after an average 5 years. Twenty-four patients had unilateral procedures. The follow-up examination included a standardized questionnaire and clinical and radiological examinations. Pain relief was achieved in all cases. The patients considered that 32 of their operated hands had improved function, while two had not improved. All patients were satisfied with the final postoperative result. Adduction of the thumb to the index finger, and opposition to the tip of the little finger was possible in all cases. Weakness, in comparison to the other thumb, of lateral pinch (71%; P=0.0001), tip pinch (74%; P=0.007), and grip strength (85%; P=0.006) were observed. The first web span was preserved in all hands. Calculation of the trapezial space ratio demonstrated only slight, insignificant shortening (7%; P=0.06) of the thumb ray. No significant correlations between the postoperative trapezial space ratio and lateral pinch strength, tip pinch strength, and grip strength were observed. We conclude that excision of the trapezium and Gelfoam interposition has no specific complications and is a reliable surgical treatment for osteoarthritis of the trapeziometacarpal joint.
Molecular Changes in Hepatocellular Dysplastic Nodules on Microdissected Liver Biopsies
Authors: Maggioni Marco , Coggi Guido , Cassani Barbara , Bianchi Paolo , Romagnoli Solange , Mandelli Alessandra , Borzio Mauro , Colombo Piergiuseppe , Roncalli Massimo
Published: June 2003

The genetic profile of dysplastic hepatocellular nodules arising in cirrhosis is poorly understood. We assessed loss of heterozygosity (LOH) and microsatellite instability (MI) in 10 dysplastic nodules (4 low–grade and 6 high–grade) with surrounding cirrhosis and in 10 hepatocellular carcinomas (HCC). Six microsatellite loci were selected and investigated on microdissected needle biopsies. Twenty–four (24.4%) informative loci showed allelic loss, while MI was seen in 3 loci only (3%). The most involved sites were located on chromosomes 4q (54.5%) and 8p (50%). LOH was documented in 16.6%, cirrhotic, 50% low–grade dysplastic nodules (LGDN), 83% high–grade dysplastic nodules (HGDN), and 70% malignant nodules. LOH at multiple loci was increasingly seen from cirrhotic to HGDN, but not from the latter to HCC. The fractional allelic loss (FAL) was significantly increased in dysplastic and neoplastic nodules as compared with cirrhosis (P < .01). The progressive accumulation of genetic changes in cirrhotic, dysplastic, and malignant hepatocellular nodules is in keeping with a multistep process of carcinogenesis; within this spectrum, HGDN can be considered advanced precursors of HCC.
Fine Specificity of T Cells Reactive to Human Pdc–E2 163–176 Peptide, the Immunodominant Autoantigen in Primary Biliary Cirrhosis: Implications for Molecular Mimicry and Cross–Recognition Among Mitochondrial Autoantigens
Authors: Shigematsu Hirohisa , Shimoda Shinji , Nakamura Minoru , Matsushita Sho , Nishimura Yasuharu , Sakamoto Norihiro , Ichiki Yasunori , Niho Yoshiyuki , Gershwin Eric M. , Ishibashi Hiromi
Published: June 2003

The anti–mitochondrial antibody response in primary biliary cirrhosis (PBC) is primarily directed at E2 components of PDC, OGDC, and BCOADC, and E3BP. Previous work has shown that the immunodominant autoreactive T– cell epitope is the PDC–E2 163–176 peptide, restricted by HLA DR53. To address molecular mimicry and cross–recognition among mitochondrial autoantigens, we analyzed reactivity, including agonism and antagonism assays, to a series of single amino acid-substituted peptides using cloned T–cell lines in PBC and controls. Interestingly, fine specificities were unique for every single T–cell clone, but the clones could be categorized into two distinct groups based on recognition motifs of the T–cell receptor (TCR) ligand: group A 170ExDK173 and group B168EIExD172. 170E is the most critical TCR contact residue for both groups of cloned T–cell lines, whereas 173K and 168E are the critical TCR contact residues for group A and group B cloned T–cell lines, respectively. More importantly, some group A-cloned T–cell lines cross–reacted to human E3BP 34–47, human OGDC–E2 100–113, and several peptides derived from various microbial proteins carrying an ExDK motif, whereas group B-cloned T–cell lines reacted only to E3BP 34–47 carrying an EIExD motif. Furthermore, an RGxG motif was exclusively found in the complementarity–determining region (CDR3) of the TCR Vβ in the group B-cloned T–cell lines, while G, S, and/or R were frequently found in the CDR3 of the TCR Vβ in the group A-cloned T–cell lines. These data provide a framework for understanding molecular mimicry among mitochondrial antigens.
Pathophysiologic Importance of E– and L–Selectin for Neutrophil–Induced Liver Injury During Endotoxemia in Mice
Authors: Lawson Judy A. , Burns Alan R. , Farhood Anwar , Bajt Mary Lynn , Collins Robert G. , Smith Wayne C. , Jaeschke Hartmut
Published: June 2003

Neutrophils can cause parenchymal cell injury in the liver during ischemia–reperfusion and endotoxemia. Neutrophils relevant for the injury accumulate in sinusoids, transmigrate, and adhere to hepatocytes. To investigate the role of E– and L–selectin in this process, C3Heb/FeJ mice were treated with 700 mg/kg galactosamine and 100 μg/kg endotoxin (Gal/ET). Immunogold labeling verified the expression of E–selectin on sinusoidal endothelial cells 4 hours after Gal/ET injection. In addition, Gal/ET caused up–regulation of Mac–1 (CD11b/CD18) and shedding of L–selectin from circulating neutrophils. Gal/ET induced hepatic neutrophil accumulation (422 ± 32 polymorphonuclear leukocytes [PMN]/50 high power fields [HPF]) and severe liver injury (plasma alanine transaminase [ALT] activities: 4,120 ± 960 U/L; necrosis: 44 ± 3%) at 7 hours. Treatment with an anti-E–selectin antibody (3 mg/kg, intravenously) at the time of Gal/ET administration did not significantly affect hepatic neutrophil accumulation and localization. However, the anti-E–selectin antibody significantly attenuated liver injury as indicated by reduced ALT levels (-84%) and 43% less necrotic hepatocytes. In contrast, animals treated with an anti-L–selectin antibody or L–selectin gene knock out mice were not protected against Gal/ET–induced liver injury. However, E–, L–, and P–selectin triple knock out mice showed significantly reduced liver injury after Gal/ET treatment as indicated by lower ALT levels (-65%) and reduced necrosis (-68%). Previous studies showed that circulating neutrophils of E–selectin-overexpressing mice are primed and activated similar to neutrophils adhering to E–selectin in vitro. Therefore, we conclude that blocking E–selectin or eliminating this gene may have protected against Gal/ET–induced liver injury in vivo by inhibiting the full activation of neutrophils during the transmigration process.
Mucosal Immunity and Primary Biliary Cirrhosis: Presence of Antimitochondrial Antibodies in Urine
Authors: Tanaka Atsushi , Nalbandian Gregory , Leung Patrick S.C. , Benson Gordon D. , Munoz Santiago , Findor Jorge A. , Branch Andrea D. , Coppel Ross L. , Ansari Aftab A. , Gershwin Eric M.
Published: June 2003

We have shown that IgA–class antimitochondrial autoantibodies (AMA) can be detected in the bile and saliva of patients with PBC, suggesting that AMA are secreted into the luminal fluid across bile ducts and salivary glands. These data prompted us to determine whether AMA of the IgA isotype may be transported across other epithelial mucosa. Therefore, we tested for the presence of AMA in the urine specimens of 83 patients with PBC and 58 non–PBC controls including healthy individuals and patients with other liver diseases. Patients enrolled in this study had no history of renal disease, and we confirmed there was less than 50 μg/mL of protein in each of the urine specimens. Interestingly, we found that AMA were present in the urine of 71/83 (86%) of all patients with PBC and in 71/78 (91%) of patients with PBC that were serum AMA positive. In contrast, AMA were not detected in any of the 58 control urine specimens. Of particular interest, AMA of the IgA isotype was present in 57/83 (69%) of patients with PBC, and in 52 of these 57, we found secretory–type IgA. In a nested random subgroup of urine samples, the prevalence of the IgA2 AMA was 6/18 (33%), significantly lower than in matched serum samples, 13/16 (81%, P = .007). These data show that AMA of the IgA isotype is secreted into urine from the uroepithelium of patients with PBC, and support the thesis that PBC originated from either a mucosal challenge or a loss of mucosal tolerance.
Evidence for An Endothelium–Derived Hyperpolarizing Factor in the Superior Mesenteric Artery From Rats With Cirrhosis
Authors: Barriere Eric , Tazi Khalid A. , Rona Jean-Pierre , Pessione Fabienne , Heller Jörg , Lebrec Didier , Moreau Richard
Published: June 2003

In cirrhosis, in splanchnic arteries, endothelium–dependent relaxation may persist even if overactive nitric oxide synthase (NOS) and cyclooxygenase (COX) are inhibited. In normal arteries, a significant endothelium–dependent relaxation to acetylcholine persists after NOS/COX inhibition. This relaxation is caused by smooth muscle cell (SMC) membrane hyperpolarization, which is sensitive to a combination of the potassium channel blockers apamin and charybdotoxin, and is mediated by an endothelium–derived hyperpolarizing factor (EDHF). The aim of this study was to detect EDHF and evaluate its pathophysiologic role in isolated superior mesenteric arteries from cirrhotic rats. Arterial rings were obtained and exposed to N
w–nitro–L–arginine (L–NNA, a NOS inhibitor) and indomethacin (a COX inhibitor). Acetylcholine–induced membrane potential responses and concentration–response curves to the relaxant of acetylcholine were obtained with and without apamin plus charybdotoxin. Acetylcholine–induced responses were measured in certain rings from endothelium–denuded arteries. Contractions caused by the α1–adrenoceptor agonist phenylephrine were obtained in cirrhotic and normal rings with and without apamin and charybdotoxin. Significant acetylcholine–induced, endothelium–dependent, apamin– and charybdotoxin–sensitive, SMC membrane hyperpolarization and relaxation were found. An apamin– and charybdotoxin–sensitive hyporesponsiveness to the contractile action of phenylephrine was found in cirrhotic rings. In conclusion, in cirrhotic rats, in the superior mesenteric artery exposed to NOS/COX–inhibitors, an EDHF exists that may replace NOS/COX products to induce endothelium–dependent arterial relaxation.
Incubation Phase of Acute Hepatitis B in Man: Dynamic of Cellular Immune Mechanisms
Authors: Webster George J.M. , Reignat Stephanie , Maini Mala K. , Whalley Simon A. , Ogg Graham S. , King Abigail , Brown David , Amlot Peter L. , Williams Roger , Vergani Diego , Dusheiko Geoffrey M. , Bertoletti Antonio
Published: June 2003

After hepatitis B virus (HBV) infection, liver injury and viral control have been thought to result from lysis of infected hepatocytes by virus–specific cytotoxic T cells. Patients are usually studied only after developing significant liver injury, and so the viral and immune events during the incubation phase of disease have not been defined. During a single–source outbreak of HBV infection, we identified patients before the onset of symptomatic hepatitis. The dynamics of HBV replication, liver injury, and HBV–specific CD8+ and CD4+ cell responses were investigated from incubation to recovery. Although a rise in alanine transaminase (ALT) levels was present at the time of the initial fall in HBV–DNA levels, maximal reduction in virus level occurred before significant liver injury. Direct ex vivo quantification of HBV–specific CD4+ and CD8+ cells, by using human leukocyte antigen (HLA) class I tetramers and intracellular cytokine staining, showed that adaptive immune mechanisms are present during the incubation phase, at least 4 weeks before symptoms. The results suggest that the pattern of reduction in HBV replication is not directly proportional to tissue injury during acute hepatitis B in humans. Furthermore, because virus–specific immune responses and significant reductions in viral replication are seen during the incubation phase, it is likely that the immune events central to viral control occur before symptomatic disease.
Hepatitis C Virus Core Protein Activates the Mapk/Erk Cascade Synergistically With Tumor Promoter Tpa, But Not With Epidermal Growth Factor or Transforming Growth Factor α
Authors: Hayashi Junpei , Aoki Hiroshi , Kajino Kazunori , Moriyama Mitsuhiko , Arakawa Yasuyuki , Hino Okio
Published: June 2003

Persistent hepatitis C virus (HCV) infection is associated with the development of human hepatocellular carcinoma (HCC), although the mechanism of HCV–related hepatocarcinogenesis remains unclear. Recently, however, the close relationships between the development of HCC and the mitogen–activated protein kinase (MAPK)/extracellular signal-regulated protein kinase (ERK) cascade have been described. In the present study, we investigated the effects of HCV core protein on this MAPK/ERK cascade. HCV core protein significantly activated the MAPK/ERK cascade, including Elk1. We also examined whether HCV core protein acted synergistically along with hepatocyte mitogen–mediated MAPK/ERK activation. Interestingly, Elk–1 activities were further enhanced by the tumor promoter, 12–O–tetradecanoyl phorbol 13–acetate (TPA), but not by hepatocyte mitogens (epidermal growth factor [EGF] and transforming growth factor α [TGF–α]) in NIH3T3 cells and HepG2 cells expressing HCV core protein. Moreover, the MAPK/ERK activation by HCV core protein was blocked in the presence of the specific MEK1 inhibitor, PD98059. These results indicate that ERK activation by HCV core protein may be independent of hepatocyte mitogen–mediated signaling but synergistic with TPA, and HCV core protein may function at MEK1 or farther upstream of that component.
Guest editorial
Authors: Leopold John , Karsten Luchien
Published: June 2003

Introduces the special issue on time and management which draws together analyses of these issues from across the European Union.
Combined Contributions of Streptolysin O and Streptolysin S to Virulence of Serotype M5Streptococcus pyogenesStrain Manfredo
Authors: Fontaine Michael C. , Lee Jeong Jin , Kehoe Michael A.
Published: June 2003

Streptolysin O (SLO) and streptolysin S (SLS) are potent cytolytic toxins produced by almost all clinical isolates of group A streptococci (GAS). Allele-replacement mutagenesis was used to construct nonpolar (in-frame) deletion mutations in thesloandsagBgenes of the serotype M5 GAS strain Manfredo, producing isogenic single and double SLO- and SLS-defective mutants. In contrast to recent reports on SLS-defective insertion mutants (I. Biswas, P. Germon, K. McDade, and J. Scott, Infect. Immun. 69:7029-7038, 2001; Z. Li, D. Sledjeski, B. Kreikemeyer, A.Podbielski, and M. Boyle, J. Bacteriol. 181:6019-6027, 1999), none of the mutants described here had notable pleiotropic effects on the expression of other virulence factors examined. Comparison of isogenic parent and mutant strains in various virulence models revealed no differences in their abilities to multiply in human blood or in their 50% lethal doses (LD50s) upon intraperitoneal infection of BALB/c mice. A single log unit difference in the LD50s of the parent and SLS-defective mutant strains was observed upon infection by the subcutaneous (s.c.) route. Comparisons over a range of infective doses showed that both SLO and SLS contributed to the early stages of infection and to the induction of necrotic lesions in the murine s.c. model. Individually, each toxin made an incremental contribution to virulence that was not apparent at higher infective doses, although the absence of both toxins reduced virulence over the entire dose range examined. Interestingly, in some cases, the contribution of SLO to virulence was clear only from an analysis of the double-mutant strain, highlighting the value of not confining virulence studies to mutant strains defective in the expression of only single virulence factors.
Tripalmitoyl-S-Glyceryl-Cysteine-Dependent OspA Vaccination of Toll-Like Receptor 2-Deficient Mice Results in Effective Protection fromBorrelia burgdorferiChallenge
Authors: Yoder Alyson , Wang Xiaohui , Ma Ying , Philipp Mario T. , Heilbrun Marta , Weis John H. , Kirschning Carsten J. , Wooten R. Mark , Weis Janis J.
Published: June 2003

Toll-like receptor 2 (TLR2) is a transmembrane signal transducer for tripalmitoyl-S-glyceryl-cysteine (Pam3Cys)-modified lipoproteins, including OspA from the Lyme disease spirocheteBorrelia burgdorferi. The Pam3Cys modification provides adjuvant activity for inducing humoral responses, suggesting that TLR2 could function as the adjuvant receptor for the OspA vaccine. The importance of TLR2 in the humoral response to OspA was confirmed, because overall levels of immunoglobulin G (IgG) were reduced in TLR2-deficient mice, when compared with those in wild-type mice. However, the levels of production of IgG1 were similar in both mouse strains, and the levels of induction of protective immunity were comparable. Unlipidated OspA was not immunogenic in wild-type or TLR2-deficient mice, indicating the lipid modification was active in the absence of TLR2. These findings indicate that the Pam3Cys modification of bacterial lipoprotein has adjuvant properties independent of TLR2 signaling.
Cholera Holotoxin Assembly Requires a Hydrophobic Domain at the A-B5Interface: Mutational Analysis and Development of an In Vitro Assembly System
Authors: Tinker Juliette K. , Erbe Jarrod L. , Hol Wim G. J. , Holmes Randall K.
Published: June 2003

Cholera toxin (CT) and relatedEscherichia colienterotoxins LTI and LTIIb have a conserved hydrophobic region at the AB5interface postulated to be important for toxin assembly. Hydrophobic residue F223 in the A subunit of CT (CTA) as well as residues 174, L77, and T78 in the B subunit of CT (CTB) were replaced individually with aspartic acid, and the resulting CTA and CTB variants were analyzed for their ability to assemble into holotoxin in vivo. CTA-F223D holotoxin exhibited decreased stability and toxicity and increased susceptibility to proteolysis by trypsin. CTB-L77D was unable to form functional pentamers. CTB-I74D and CTB-T78D formed pentamers that bound to GM1andd-galactose but failed to assemble with CTA to form holotoxin. In contrast, CTB-T78D and CTA-F223H interacted with each other to form a significant amount of holotoxin in vivo. Our findings support the importance of hydrophobic interactions between CTA and CTB in holotoxin assembly. We also developed an efficient method for assembly of CT in vitro, and we showed that CT assembled in vitro was comparable to wild-type CT in toxicity and antigenicity. CTB-I74D and CTB-T78D did not form pentamers or holotoxin in vitro, and CTA-F223D did not form holotoxin in vitro. The efficient system for in vitro assembly of CT described here should be useful for future studies on the development of drugs to inhibit CT assembly as well as the development of chimeric CT-like molecules as potential vaccine candidates.
Yersinia pestisTonB: Role in Iron, Heme, and Hemoprotein Utilization
Authors: Perry Robert D. , Shah Jessica , Bearden Scott W. , Thompson Jan M. , Fetherston Jacqueline D.
Published: June 2003

InYersinia pestis, the siderophore-dependent yersiniabactin (Ybt) iron transport system and heme transport system (Hmu) have putative TonB-dependent outer membrane receptors. Here we demonstrate that hemin uptake and iron utilization from Ybt are TonB dependent. However, the Yfe iron and manganese transport system does not require TonB.
Leptin Modulates Neutrophil Phagocytosis ofKlebsiella pneumoniae
Authors: Moore Sharlene I. , Huffnagle Gary B. , Chen Gwo-Hsiao , White Eric S. , Mancuso Peter
Published: June 2003

Leptin is a pleiotropic hormone-cytokine known to regulate energy homeostasis and immune function. Neutrophils from leptin-deficient mice exhibited impaired phagocytosis ofKlebsiella pneumoniaeopsonized with serum containing complement and reduced CD11b expression that could be restored with exogenous leptin. These results suggest that leptin is required for normal neutrophil complement-mediated phagocytosis of bacteria.
Antigen Processing of the Heptavalent Pneumococcal Conjugate Vaccine Carrier Protein CRM197Differs Depending on the Serotype of the Attached Polysaccharide
Authors: Leonard Ethan G. , Canaday David H. , Harding Clifford V. , Schreiber John R.
Published: June 2003

The pneumococcal (Pn) conjugate vaccine includes seven different polysaccharides (PS) conjugated to CRM197. Utilizing antigen-processing cells and a CRM197-specific mouse T-cell hybridoma, we found that the serotype of conjugated PnPS dramatically affected antigen processing of CRM197. Unconjugated CRM197and serotype conjugates 14 and 18C were processed more efficiently.
Hearing in hooktip moths (Drepanidae: Lepidoptera)
Authors: Surlykke Annemarie , Yack Jayne E. , Spence Andrew J. , Hasenfuss Ivar
Published: June 2003

This study presents anatomical and physiological evidence for a sense of hearing in hooktip moths (Drepanoidea). Two example species, Drepana arcuata and Watsonalla uncinula, were examined. The abdominal ears of drepanids are structurally unique compared to those of other Lepidoptera and other insects, by having an internal tympanal membrane, and auditory sensilla embedded within the membrane. The tympanum is formed by two thin tracheal walls that stretch across a teardrop-shaped opening between dorsal and ventral air chambers in the first abdominal segment. There are four sensory organs (scolopidia) embedded separately between the tympanal membrane layers: two larger lateral scolopidia within the tympanal area, and two smaller scolopidia at the medial margin of the tympanal frame. Sound is thought to reach the tympanal membrane through two external membranes that connect indirectly to the dorsal chamber.

The ear is tuned to ultrasonic frequencies between 30 and 65 kHz, with a best threshold of around 52 dB SPL at 40 kHz, and no apparent difference between genders. Thus, drepanid hearing resembles that of other moths,indicating that the main function is bat detection. Two sensory cells are excited by sound stimuli. Those two cells differ in threshold by approximately 19 dB. The morphology of the ear suggests that the two larger scolopidia function as auditory sensilla; the two smaller scolopidia, located near the tympanal frame, were not excited by sound. We present a biophysical model to explain the possible functional organization of this unique tympanal ear.
Hypoxia and Heat Inhibit Inducible Nitric Oxide Synthase Gene Expression by Different Mechanisms in Rat Hepatocytes
Authors: Inoue Tomohisa , Kwon A-Hon , Oda Michio , Kaibori Masaki , Kamiyama Yasuo , Nishizawa Mikio , Ito Seiji , Okumura Tadayoshi
Published: June 2003

Ischemia/reperfusion contributes to the hepatic injury in resection and transplantation of the liver. However, the precise mechanisms involved in hypoxia stress remain to be clarified. Pro–inflammatory cytokines including interleukin 1β (IL–1β) induce a gene expression of inducible nitric oxide synthase (iNOS) and produce nitric oxide, which exerts either a cytoprotective or toxic effect. In this report, we found that hypoxia and heat markedly inhibited the induction of nitric oxide production stimulated by IL–1β in rat cultured hepatocytes. Both treatments also abolished the induction of iNOS protein and mRNA. However, hypoxia could not prevent either degradation of an inhibitory protein (IκBα) of nuclear factor–κB (NF–κB) or translocation of NF–κB to the nucleus, whereas heat inhibited both of the IκBα degradation and NF–κB translocation. Transfection experiments with iNOS promoter construct revealed that hypoxia as well as heat significantly inhibited the transactivation of iNOS gene. Further, a hypoxia–response element located in the promoter was not involved in the inhibition of iNOS induction by hypoxia. These results indicate that hypoxia and heat suppress iNOS gene induction at the transcriptional level through different mechanisms. Reduction of nitric oxide production under hypoxic conditions may be implicated in the cellular damage or protection during hepatic ischemia/reperfusion.