bluuebunny/crossref_metadata_2025 huggingface dataset:
Kinetics of HBV DNA and HBsAg in acute hepatitis B patients with and without coinfection by other hepatitis viruses
Authors: Chulanov Vladimir P. , Shipulin German A. , Schaefer Stephan , Gerlich Wolfram H.
Published: January 2003

The kinetics of hepatitis B virus (HBV) and its surface antigen (HBsAg) during acute hepatitis has not yet been studied accurately in a representative number of patients. The influence of coinfecting hepatitis viruses during the acute phase of infection is not known. Three to four serum samples from 21 patients with acute HBV monoinfection and 27 with coinfection were taken at intervals of 6–10 days and analyzed for the number of HBV genome equivalents (ge) by real time polymerase chain reaction (PCR) and for HBsAg quantity using Laurell electrophoresis. Log HBV ge/ml decreased during the follow‐up from 6.8 ± 1.1 to 5.1 ± 1.0 to 4.2 ± 0.8 to 3.3 ± 1.1 (mean ± SD). The half‐life times of HBV ge increased from 1.6 days at the beginning to 4 days at the end. HBsAg decreased much slower: from 38 to 23 to 12 to3.8 μg/ml. Half‐life time was around 8 days at the beginning and 5.7 days at the end, but 11 patients showed a rapid elimination of HBsAg and HBV DNA. Hepatitis C virus (HCV) coinfection did not change the kinetics of HBV ge and HBsAg significantly. A moderate but significant suppression of HBV ge levels was observed in hepatitis D virus (HDV) coinfected patients. HBsAg levels were, however, enhanced in this cohort. In conclusion, the data suggest that expression and elimination of HBV is in most patients with acute hepatitis B not altered by coinfecting hepatitis viruses. The initial decrease of HBV ge and HBsAg in serum appears to be caused by decay or non‐specific removal in the absence of replacement. J. Med. Virol. 69:313–323, 2003. © 2003 Wiley‐Liss, Inc.
An outbreak of HBV and HCV infection in a paediatric oncology ward: Epidemiological investigations and prevention of further spread
Authors: Dumpis Uga , Kovalova Žanna , Jansons Juris , Čupane Liene , Sominskaya Irina , Michailova Marija , Karayiannis Peter , Gardovska Dace , Viazov Sergey , Ross Stefan , Roggendorf Michael , Pumpens Paul
Published: January 2003

Hospital‐acquired hepatitis B (HBV) and C virus (HCV) infections continue to occur despite increased awareness of this problem among the medical community. One hundred six patients were infected in a haematology oncology ward for children, over the time period 1996 to 2000. Serum samples from 45 such patients and 3 from infected medical personnel were used for nucleic acid amplification. HBV core, as well as HCV core and hypervariable region 1 (HVR1) nucleotide sequences, were analysed by phylogenetic tree analysis, in order to characterise the epidemiological pattern of viral transmission on the ward. Samples from 32 patients were positive for HBV‐DNA or HCV‐RNA by PCR. Ten patients were positive for both markers. Seventeen out of twenty‐three HCV core gene sequences were found to be evolutionarily related and clustered separately from other local sequences in the phylogenetic tree, indicating nosocomial transmission. This was confirmed by analysis of HVR1 gene sequences. One nurse and one physician from the ward were HCV RNA positive, but their HCV sequences were not related evolutionarily to those of the patient cluster. Fifteen out of nineteen HBV core gene sequences were also clustered together and were positioned separately in the relevant tree. Epidemiological investigation excluded a common source infection and indicated that spread of infection was most likely due to inappropriate infection control measures on the ward. No obvious risk factors for transmission were identified during the retrospective survey in patients with related sequences, except use of multidose vials for saline and poor staff compliance with routine hand hygiene procedures. The preventive measures that were introduced reduced the incidence of infection significantly. No new cases of HBV infection and only three anti‐HCV seroconversions occurred over a period of 19 months. The introduction and maintenance of strict prevention measures over a 2 year period, combined with HBV vaccination, reduced significantly the incidence of new HCV and HBV infections. J. Med. Virol. 69:331–338, 2003. © 2003 Wiley‐Liss, Inc.
Prevalence and clinical significance of circulating cryoglobulins in HIV‐positive patients with and without Co‐infection with hepatitis C virus
Authors: Fabris Paolo , Tositti Giulia , Giordani Maria Teresa , Romanò Luisa , Betterle Corrado , Pignattari Elena , Tagliaferri Cinzia , Muratori Paolo , Manfrin Vinicio , de Lalla Fausto
Published: January 2003

Although hepatitis C virus (HCV) is a recognized cause of circulating cryoglobulins, the role of human immunodeficiency virus (HIV) in the pathogenesis of cryoglobulinemia has not been investigated extensively. To evaluate the prevalence of circulating cryoglobulins and to assess the relationship with clinical and virological parameters, 162 HIV‐positive subjects (84 anti‐HCV+) were tested for cryoglobulins, C3, C4, RF, autoantibodies, HIV‐viral titer, and CD4+ count. Anti‐HCV‐positive subjects were tested for HCV‐RNA, HCV‐viral titer, and HCV genotype. All patients were examined for the presence of signs or symptoms of vasculitis and tested for cryoglobulins using a standard biochemical assay. Cryoglobulins were found in 30 (18.5%) cases. Of the 30 positive cases, 29 (96.7%) were anti‐HCV‐positive and 28 (93.3%) HCV‐RNA‐positive. The presence of cryoglobulins was significantly associated (P < 0.01) with HCV‐RNA positivity (OR = 27), liver cirrhosis (OR = 16), decreased levels of C3 (OR = 8.6), C4 (OR = 13.6), increased levels of IgG and IgM (OR = 6.1 and 7.9, respectively), and RF positivity (OR = 6.3), but was unrelated to CD4+ cell count, HIV viral load, diagnosis of AIDS, HCV viral load and the presence of autoantibodies. Interestingly, the presence of cryoglobulins was not significantly associated with signs and symptoms commonly associated with cryoglobulinemia. In conclusion, HIV infection does not seem to play a significant role in the production of circulating cryoglobulins, which strongly correlates with HCV co‐infection and liver cirrhosis. Typical signs and symptoms of cryoglobulinemia do not correlate with the detection of circulating cryoglobulins in HIV and HCV patients. J. Med. Virol. 69:339–343, 2003. © 2003 Wiley‐Liss, Inc.
Intermittent detection of hepatitis C virus (HCV) in semen from men with human immunodeficiency virus type 1 (HIV‐1) and HCV
Authors: Pasquier Christophe , Bujan Louis , Daudin Myriam , Righi Laurence , Berges Laetitia , Thauvin Laurence , Berrebi Alain , Massip Patrice , Puel Jacqueline , Izopet Jacques
Published: January 2003

HCV is usually transmitted via the blood, but HCV RNA has been detected recently in seminal fluid. This study was done to study HCV seminal shedding and factors that could influence the presence of HCV in the seminal fluid of men coinfected with HCV and HIV‐1. HCV and HIV‐1 genomes were assayed in multiple paired blood and semen samples obtained from 35 men enrolled in an assisted medical procreation protocol. HCV RNA was found intermittently in semen samples from 9 patients (25.7%). Samples from 9 men with HCV RNA in their semen and 26 men without were compared to further analyze these parameters. No correlation was found between HCV RNA in the seminal fluid and age, HCV virus load, the duration of HIV‐1 infection, HIV treatment, the CD4+ cell count, HIV‐1 virus load or HIV‐1 detection in the semen. The intermittent detection of HCV RNA in semen samples support the systematic search for HCV RNA in semen and the use of processed spermatozoa in assisted medical procreation of infertile HCV serodiscordant couples. J. Med. Virol. 69:344–349, 2003. © 2003 Wiley‐Liss, Inc.
Hepatitis C virus molecular epidemiology in Uzbekistan
Authors: Kurbanov Fuat , Tanaka Yasuhito , Sugauchi Fuminaka , Kato Hideaki , Ruzibakiev Ruslan , Zalyalieva Mariam , Yunusova Zulhumor , Mizokami Masashi
Published: January 2003

The aim of this study was to identify hepatitis C virus (HCV) genotypes and to estimate their prevalence in various risk groups and the regional distribution in Uzbekistan. Preliminary serological screening of 1,269 subjects revealed 6.5% anti‐HCV‐positive in a general population, 27.1% in patient groups, and 51.7% among intravenous drug users. HCV genotypes of 104 anti‐HCV‐positive subjects were determined using a PCR‐genotyping system in core region, and the results were supported by nucleotide sequencing of the NS5B region. Genotype 1b identified in total 64.2%, was the most prevalent. The genotype 3a identified in 25.0% was the second one distributed. HCV genotypes 2a, 1a, 2b, and 3b were identified in 3.8%, 2.9%, 2.9%, and 1.0% of cases, respectively. The intravenous drug users were distinguished from other groups by having the highest prevalence of genotype 3a, i.e., 50.0%, higher than the 33.3% for genotype 1b in this group. Geographically, genotype 1b was common; genotype 3a was also found frequently in all three regions. Uncommon HCV genotypes (1a, 2a, 2b, and 3b) were found in comparatively greater variability in the western region. Molecular evolutionary analysis based on the NS5B region did not reveal specific clustering or indigenous strains among Uzbekistan HCV isolates. In summary, two main mechanisms of HCV infection distribution were observed in Uzbekistan: HCV 1b genotype infection is widespread through blood products, and HCV 3a genotype infection is spreading through the growing number of intravenous drug users. J. Med. Virol. 69:367–375, 2003. © 2003 Wiley‐Liss, Inc.
Association of amino acid substitution pattern in nonstructural protein 5A of hepatitis C virus genotype2a low viral load and response to interferon monotherapy
Authors: Akuta Norio , Suzuki Fumitaka , Tsubota Akihito , Suzuki Yoshiyuki , Hosaka Tetsuya , Someya Takashi , Kobayashi Masahiro , Saitoh Satoshi , Arase Yasuji , Ikeda Kenji , Kumada Hiromitsu
Published: January 2003

Patients with low titer (<0.5 mEq/ml) of hepatitis C virus (HCV) genotype 2a achieve high and sustained response (SR) rates to interferon (IFN) monotherapy, but we also encounter patients who are resistant to therapy. We explored the relationship between response to IFN and virological differences in such patients. We evaluated 159 consecutive naive patients with low titer of HCV genotype 2a who received IFN monotherapy. A case‐control study matched for age, sex, and viral load was conducted to examine the substitution patterns in amino acid positions (amino acids) 2163–2254 of nonstructural (NS) 5A between nonresponders to ideal IFN dose (≥500 million units) (nonresponders; NR) and responder to less than ideal dose. Overall, 82.4% achieved SR. The substitution numbers in amino acids 2193–2254 were higher in SR than NR patients (P < 0.05). High proportions of patients with substitution at amino acid 2205 (mainly threonine [T] instead of alanine [A]), dual amino acids 2169 and 2205 (mainly A‐T instead of T‐A), and those without substitution at amino acids 2227 were NR (P < 0.05). Four of 7 NR patients achieved SR after receiving a second course of IFN. Their amino acids patterns at positions probably associated with sensitivity to IFN did not change at the start of initial and second therapies except for one patient, and they had lower viral load and were treated with higher IFN dose in the second course compared with the initial course. Our results suggest that substitution patterns in NS5A in patients with low titer of HCV genotype 2a may affect their response to IFN, but the response to therapy may be affected by mechanisms other than substitutions in this region. J. Med. Virol. 69:376–383, 2003. © 2003 Wiley‐Liss, Inc.
Hepatitis C virus infection among pregnant women in Yaounde, Cameroon: Prevalence, viremia, and genotypes
Authors: Njouom Richard , Pasquier Christophe , Ayouba Ahidjo , Sandres‐Sauné Karine , Mfoupouendoun Jermie , Mony Lobe Marcel , Tene Gilbert , Thonnon Jocelyn , Izopet Jacques , Nerrienet Eric
Published: January 2003

Central Africa is considered to be an area of high endemic hepatitis C infection. To determine the prevalence of anti‐HCV antibodies, HCV RNA, and the genotype distribution in Cameroon, 1,494 pregnant women attending antenatal care units in Yaounde, Cameroon were screened for HCV infection. Anti‐HCV antibodies were detected with a 3rd generation ELISA (Monolisa anti‐HCV plus version 2, BioRad, Richmond, CA). All anti‐HCV antibody‐positive sera were then tested with another 3rd generation ELISA (AxSYM® HCV version 3, Abbott Laboratories, Abbott Park, IL) and subsequently for HCV RNA (Amplicor HCV, Roche Diagnostics, Basel, Switzerland). Genotype was determined by phylogenetic analysis of the NS5b gene. Seventy‐three pregnant women were found to be anti‐HCV antibody positive by the first ELISA, but only 28 were anti‐HCV positive by both ELISA. The prevalence of anti‐HCV antibodies was thus 1.9% (28/1,494) (95% CI: 1.3–2.7%). 21/28 (75%) of the positive samples by both ELISA were HCV RNA positive. The 45 samples that were HCV antibody negative by the second ELISA were also HCV RNA negative. The HCV subtypes identified were 1a (24%), 2f (38%) and 4f (38%). In contrast to previous studies, anti‐HCV antibodies were rare among pregnant women in Cameroon. The percentage of HCV seropositive pregnant women who had circulating HCV RNA was similar to that observed in Europe. Several HCV genotypes were found in Cameroon. J. Med. Virol. 69:384–390, 2003. © 2003 Wiley‐Liss, Inc.
Swine HEV infection in south India and phylogenetic analysis (1985–1999)
Authors: Arankalle V.A. , Chobe L.P. , Walimbe A.M. , Yergolkar P.N. , Jacob G.P.
Published: January 2003

Hepatitis E is endemic in India. It was recently noted that although all the Indian human hepatitis E virus (HEV) isolates (1976–2001) were placed in genotype I, the swine HEV recovered from western India (2000) belonged to genotype IV. This was in contrast to reports from the United States and Taiwan wherein both human and swine HEV belonged to the same genotype, i.e., genotypes III and IV, respectively. In order to validate these findings further, we retrospectively examined serum samples collected from pigs from southern India. Sequential serum samples from 45 (1985–1987) and 12 (1999) pigs from Karnataka state, south India, were screened for the presence of HEV RNA (nested PCR) and IgG‐anti‐HEV (ELISA). PCR products (Open Reading Frame‐2 region) were sequenced and subjected to phylogenetic analysis. In this study, 42/45 (1985–1987) and 12/12 (1999) pigs showed seroconversion to IgG anti‐HEV antibodies, with a mean age at seroconversion of 4.8 ± 1.6 months. Four samples collected in 1999 and two samples collected during 1985 were HEV RNA positive. All swine HEV sequences clustered with genotype IV, demonstrating that swine HEV was prevalent among south Indian pigs for at least for 16 years and, similar to western India, belonged to genotype IV. Thus, genotype I and IV HEV continue to circulate in humans and pigs, respectively, from India. Whether swine HEV infects humans remains to be determined. J. Med. Virol. 69:391–396, 2003. © 2003 Wiley‐Liss, Inc.
Polymerase chain reaction as a rapid diagnostic tool for therapy of acute retinal necrosis syndrome
Authors: Gargiulo Franco , De Francesco Maria Antonia , Nascimbeni Giuseppe , Turano Raffaele , Perandin Francesca , Gandolfo Enrico , Manca Nino
Published: January 2003

Herpesviruses are involved in the pathogenesis of acute retinal necrosis syndrome (ARN). A rapid and accurate diagnosis of herpetic infections is crucial for prompt administration of a specific antiviral therapy. The purpose of this study was to evaluate a polymerase chain reaction (PCR)‐based assay to detect herpesvirus DNA in the aqueous humor of clinical samples from ten patients with uveitis and clinical suspicion of ARN. Samples were assayed for herpes simplex virus type 1‐2 (HSV 1‐2), varicella zoster virus (VZV) and cytomegalovirus (CMV). Clinical suspicion of ARN was confirmed for four patients. Two patients (one with bilateral ARN) tested PCR‐positive for VZV DNA and the other two were positive for HSV 1‐2 DNA. CMV DNA was not detected in any of the samples, and no sample was positive for DNA from more than one virus. The remaining patients did not show any evidence of herpesvirus DNA in their aqueous samples. Our findings demonstrate that the use of PCR for detecting herpesvirus DNA in aqueous humor of uveitic subjects may be a valuable tool for early diagnosis of acute retinal necrosis syndrome and for timely administration of a suitable therapy. J. Med. Virol. 69:397–400, 2003. © 2003 Wiley‐Liss, Inc.
Genetic characterization of new Dobrava hantavirus isolate from Greece
Authors: Nemirov Kirill , Vapalahti Olli , Papa Anna , Plyusnina Angelina , Lundkvist Åke , Antoniadis Antonis , Vaheri Antti , Plyusnin Alexander
Published: January 2003

The first complete genome sequence of Dobrava hantavirus isolated from yellow‐necked mouse Apodemus flavicollis trapped in the northeastern Greece is described. The S, M, and L segments of the Greek isolate of Dobrava virus are 1673, 3635, and 6532 nucleotides (nt) long, respectively, and encode the nucleocapsid (N) protein of 429 amino acids (aa), glycoprotein precursor of 1135 aa, and the L protein of 2151 aa. N protein contains three cysteine residues conserved in all known hantaviruses, as well as structural domains responsible for the RNA binding and presumable interaction with the apoptosis enhancer Daxx. All cysteine residues and glycosylation sites that are conserved among G1G2 sequences of all hantaviruses species were also found in the Greek isolate. The L protein contains all the polymerase motifs and structural domains found in other hantavirus polymerases. Comparison of the Greek isolate of Dobrava virus with other hantaviruses showed the highest level of sequence homology with Dobrava virus isolate from Slovenia. Other hantaviruses carried by Murinae rodents (Saaremaa, Hantaan, Seoul, and Thailand viruses) were more divergent and hantaviruses carried by Arvicolinae or Sigmodontinae rodents showed the highest genetic diversity with the Greek isolate of Dobrava. The results of phylogenetic analyses confirmed these observations and showed a monophily of all the Dobrava virus strains that, in turn, shared more ancient ancestors first with Saaremaa virus and then with other Murinae‐borne hantaviruses. J. Med. Virol. 69:408–416, 2003. © 2003 Wiley‐Liss, Inc.
EBNA‐1 sequence variations reflect active EBV replication and disease status or quiescentlatency in lymphocytes
Authors: Wang Jiin‐Tarng , Sheeng Tzung‐Shiahn , Su Ih‐Jen , Chen Jen‐Yang , Chen Mei‐Ru
Published: January 2003

EBV infects most of the global population, but only a small percentage of infected individuals develop EBV‐associated malignancies. Host and viral factors may play a role in determining the clinical outcome. Because EBNA‐1 functions as an oriP binding protein and links the episomal viral DNA to metaphase chromosomes, variation of EBNA‐1 has been suggested to contribute to determining the tissue tropism of EBV and the development of various EBV‐associated diseases. Five subtypes have been described, according to the amino acid at residue 487: P‐ala (B95‐8 prototype), P‐thr (aa 487 ala to thr), V‐val, V‐pro and V‐leu. Other studies, however, concluded that EBNA‐1 sequence variation simply reflects the geographical distribution of EBV. To clarify these possibilities, we collected DNA samples from healthy individuals and patients with various EBV‐associated diseases in Taiwan for PCR amplification and DNA sequencing. The results indicate that: 1) V‐val EBNA‐1 was detected in patients with nasopharyngeal carcinoma (NPC) and other EBV‐associated malignant diseases; 2) the prototype P‐ala strain was detected only in peripheral blood lymphocytes; 3) mixed populations of different subtypes of N‐terminal and C‐terminal sequences were observed in samples from one patient with nasopharyngeal carcinoma, one with T lymphoma and one with infectious mononucleosis sample; 4) intermediate variations between P‐ala and V‐val were observed in T‐lymphoma, Hodgkin disease and infectious mononucleosis samples; and 5) in comparison with the major sequences identified in healthy carriers, the EBNA‐1 sequences in peripheral lymphocytes from nasopharyngeal carcinoma were mixed types in 4 of 5 patients, implying increasing frequency of V‐val might correlate with the progression of nasopharyngeal carcinoma. J. Med. Virol. 69:417–425, 2003. © 2003 Wiley‐Liss, Inc.
Enterovirus infection may induce humoral immune response reacting with islet cell autoantigens in humans
Authors: Härkönen Taina , Paananen Anja , Lankinen Hilkka , Hovi Tapani , Vaarala Outi , Roivainen Merja
Published: January 2003

Molecular mimicry is one of the mechanisms by which enterovirus infections have been postulated to have a role in the pathogenesis of type 1 diabetes. Immunogenic epitopes in enterovirus capsid protein VP1 and procapsid protein VP0 have sequence similarities with diabetes‐associated epitopes in tyrosine phosphatase IA‐2/IAR and heat shock protein 60. In the present study, documented enterovirus infection was shown to induce humoral responses, that in 7% and 1% of patients cross‐reacted with the known diabetes‐associated epitopes in tyrosine phosphatase IAR and heat shock protein 60, respectively. In contrast, none of the children vaccinated against poliomyelitis had antibodies to the diabetes‐associated epitope of tyrosine phosphatases IA‐2/IAR. The antibody response studied in serum samples from six patients with coxsackievirus A9 infection was mainly targeted to capsid protein VP1. Coxsackievirus A9 infection induced antibodies cross‐reacted with one epitope in heat shock protein 60, but not with epitopes derived from other autoantigens. Most diabetic children had high levels of antibodies to both coxsackievirus and poliovirus derived VP1 peptides but the pattern of reactivity did not differ from that seen in healthy children. The reactivity of linear epitopes derived from autoantigens was low in general and associated with the presence of multiple autoantibodies in the patients. Some linear auto‐epitopes derived from tyrosine phosphatase IA‐2, glutamic acid decarboxylase 65, preproinsulin, and heat shock protein 60 were recognized by sera from diabetic patients, but not by sera from healthy children. In conclusion, enteroviruses may induce immune responses that react with islet cell autoantigens, which is a concern when a putative inactivated enterovirus vaccine is considered. J. Med. Virol. 69:426–440, 2003. © 2003 Wiley‐Liss, Inc.
IgG antibodies to human papillomavirus 16, 52, 58, and 6 L1 capsids: Case‐control study of cervical intraepithelial neoplasia in Japan
Authors: Matsumoto Koji , Yoshikawa Hiroyuki , Yasugi Toshiharu , Nakagawa Shunsuke , Kawana Kei , Takeoka Atsushi , Yaegashi Nobuo , Iwasaka Tsuyoshi , Kanazawa Koji , Taketani Yuji , Kanda Tadahito
Published: January 2003

In Japan, human papillomavirus (HPV) 16, 52, and 58 are most commonly associated with cervical intraepithelial neoplasia (CIN). By contrast, HPV6 is primarily associated with genital warts. This study was designed to evaluate the association between IgG antibody responses to common HPVs and the risk of CIN development within a Japanese population. CIN cases (n = 141) and controls (n = 109) were tested for cervical HPV DNA and serum IgG antibodies to L1 capsids of HPV16, 52, 58, and 6. Seropositivity to HPV16, 52, and 58 L1 capsids was significantly higher in CIN cases than in controls: 27%, 21%, and 31% versus 16%, 11%, and 11%, respectively (P < 0.05). HPV6 L1 seropositivity was not significantly associated with CIN lesions (P = 0.11). Presence of viral DNA for either HPV16, 52, or 58 correlated with a significant antibody response against the homologous L1 capsids but not heterologous L1 capsids. Furthermore, seropositivity to multiple types of HPV16, 52, and 58 was more strongly associated with an increased risk of CIN development than seropositivity to a single type (P for trend <0.001). These findings indicate that IgG antibodies to L1 capsids of HPV16, 52, and 58 represent an increased risk of CIN development, with antibodies to multiple types being indicative of a further increase in risk. The presence of CIN lesions in women with seropositivity to multiple types suggests that viral exposure to a given type may not be protective against infections by other types and subsequent CIN development. J. Med. Virol. 69:441–446, 2003. © 2003 Wiley‐Liss, Inc.
IgG subclasses in human immune response to wild and attenuated (vaccine) Junin virus infection
Authors: Saavedra María del Carmen , Sottosanti Josefa María , Riera Laura , Ambrosio Ana María
Published: January 2003

Different proportions of IgG subclasses have previously been reported to distinguish the immune response elicited by primary and recurrent viral infections, as well as viral vaccines. The goal of this study was to study the IgG subclasses composition in the immune response of patients with Argentine hemorrhagic fever, and vaccinees with Candid #1 strain of Junin virus. Twenty‐four individuals inoculated with Candid #1 vaccine and 67 patients with Argentine hemorrhagic fever were studied. Blood samples were drawn at 30, 60, and/or 180 days post‐inoculation with Candid #1 and 30, 60, and 90 days after clinical onset of the disease. Specific anti‐Junin virus IgG subclasses were titrated with specific human monoclonal antibody fluorescence isothiocyanate conjugate (FITC) by immunofluorescent assay (IFA). IgG1 anti‐Junin virus was found in every subject studied and IgG3 was also detected in some patients with a severe form of Argentine hemorrhagic fever. IgG2 and IgG4 were not detected in any serum sample studied. The mean titer of specific IgG1 in vaccinees was significantly lower than in patients with Argentine hemorrhagic fever (P < 0.05), but no difference was found between mild and severe cases of the disease (P > 0.05). The results of this study demonstrated a central role of IgG1 in human recovery from infection with every strain of Junin virus, an observation stressed by the immune response to Candid #1 vaccine, which resulted in no difference in IgG subclasses composition from that found in mild cases of Argentine hemorrhagic fever. J. Med. Virol. 69:447–450, 2003. © 2003 Wiley‐Liss, Inc.
Differential efficacy of a synthetic antagonist of VLA‐4 during the course of chronic relapsing experimental autoimmune encephalomyelitis
Authors: Cannella Barbara , Gaupp Stefanie , Tilton Ronald G. , Raine Cedric S.
Published: January 2003

The integrin VLA‐4 has been shown to play a key role in the entry of antigen‐specific T cells into the CNS during autoimmune demyelination. Treatment of animals with experimental autoimmune encephalomyelitis (EAE), a model of multiple sclerosis, with antibodies to VLA‐4 is known to suppress acute disease. In the present study, a synthetic antagonist of VLA‐4 (TBC 3486) was injected subcutaneously into mice adoptively sensitized for chronic relapsing EAE. TBC 3486 was administered daily for 14 days at early (before acute signs) and late time points (during chronic disease). Early treatment led to marked delay in disease onset and reduction in clinical severity and demyelination. After termination of treatment, clinical severity remained lower than in controls for more than 1 week. TBC 3486‐treated animals showing no clinical signs (at the height of disease in controls) displayed moderate levels of inflammation but little damage to myelin. Late administration of TBC 3486 to animals with chronic EAE had no effect clinically. Immunocytochemistry and Western blotting of CNS tissue from acutely treated animals supported a moderate shift toward a Th2‐type cytokine profile after treatment. Thus, TBC 3486 effectively delayed and reduced the acute (but not chronic) phase of EAE, and this amelioration correlated with changes in the inflammatory molecule profile. © 2002 Wiley‐Liss, Inc.
Distribution of γ‐aminobutyric acid receptors in cultured adrenergic and noradrenergic bovine chromaffin cells
Authors: Castro Enrique , González María Pilar , Oset‐Gasque María Jesús
Published: January 2003

Fluorescence imaging techniques for recording cytosolic [Ca2+]i from single chromaffin cells were used to characterize and discriminate between cell subpopulations containing γ‐aminobutyric acid (GABA)A and GABAB receptor subtypes. By combining this methodology with the immunoidentification of individual chromaffin cells using specific antibodies against tyrosine hydroxylase (TH), phenyl‐etanolamine‐N‐methyl transferase (PNMT), and glutamic acid decarboxylase (GAD) linked to different fluorescent probes, we have been able to ascribe single‐cell calcium responses to identified adrenergic and noradrenergic chromaffin cells. GAD enzyme is present in 30% of the chromaffin cell population, located primarily in adrenergic cells; 86% of GAD+ cells were also PNMT+. GAD expression was not correlated with the presence of GABA receptors. GABA‐responsive cells were found with equal frequency in the GAD+ and GAD− groups. However, the expression of GABA receptors was correlated with the adrenergic phenotype. [Ca2+]i responses to GABA were found more frequently in adrenergic than in noradrenergic cells. GABAA receptors are more evenly distributed; about 90% of GABA‐responsive cells have them. GABAB receptors have a more restricted distribution (present in 45% of responding cells). The coexpression of both GABAA and GABAB subtypes is the rule; only a minor subpopulation (about 12%) displays exclusively GABAB receptors. GABA receptor subtypes are distributed in a similar way when chromaffin cells are separated according to GAD+/GAD− or PNMT+/PNMT− classifications, with only minor differences. These data indicate that the intrinsic GABAergic system in the adrenal medulla is not designed as a paracrine model in which a group of cells specializes in transmitter synthesis and a different group serves as a specific target. © 2002 Wiley‐Liss, Inc.
Glutamate and aspartate do not exhibit the same changes in their extracellular concentrations in the rat striatum after N‐methyl‐D‐aspartate local administration
Authors: Parrot Sandrine , Bert Lionel , Renaud Bernard , Denoroy Luc
Published: January 2003

To determine whether glutamate (Glu) and aspartate (Asp) undergo a similar regulation of their extracellular levels, Glu and Asp were simultaneously monitored in the striatum of anesthetized rats after local N‐methyl‐D‐aspartate (NMDA) receptor stimulation, using 1‐min in vivo microdialysis coupled to capillary electrophoresis with laser‐induced fluorescence detection. Application of NMDA (10 min, 10–3 M) through the dialysis probe induced 1) an increase (+50%) in Asp during the NMDA administration and 2) a surprising biphasic effect on Glu, with a rapid increase (+30%) and a return to baseline before the end of NMDA application, followed by a second increase (+40%) occurring after and linked to the end of NMDA administration. When studied in the presence of 10 μM tetrodotoxin (TTX) or 0.1 mM Ca2+, the increase in Asp was partially TTX‐dependent, and the early increase in Glu appeared to be partially TTX and Ca2+ dependent, whereas the second increase in Glu was not. The second increase in Glu level was still present when NMDA antagonists (AP5 or MK‐801) were administered at the end of NMDA application. Finally, only extracellular Asp was increased through application of lower NMDA concentrations (10–4 M, 10–5 M), whereas extracellular Glu was not affected. In conclusion, these results suggest a differential control of Glu and Asp extracellular levels in rat striatum by distinct mechanisms linked to NMDA receptors and involving neuronal or nonneuronal release. © 2002 Wiley‐Liss, Inc.
Quantification of transcriptional activities of reporter gene constructs in primary cultures of sympathetic neurons
Authors: Pajak Fabrice , De Gois Stéphanie , Houhou Leïla , Védrine Christophe , Mallet Jacques , Berrard Sylvie
Published: January 2003

Primary cultures of sympathetic neurons provide an attractive cellular model for investigating the mechanisms of neurotransmitter phenotypic plasticity. However, it has not been possible to transfect these neurons by conventional techniques, and this has been a major impediment to molecular investigations of neuronal gene expression in this system. Here, reporter plasmids were transferred into the nuclei of cultured sympathetic neurons by microinjection. We developed and improved this procedure and were able to measure the transcriptional activities of two coinjected promoters in small groups of neurons, and even from a single neuron. Promoter activities can thus be quantified and normalized relative to that of a constitutively expressed promoter, allowing correction for variability in the injection and assay procedures. High and low promoter activities can be reliably quantified. Importantly, this method can be used not only for reporter plasmids but also for DNA fragments containing only a promoter and reporter gene without any vector sequence that might interfere with promoter. Using this approach, we measured neuronal promoter activities and found that one promoter region of the gene encoding choline acetyltransferase was up‐regulated by more than sevenfold by leukemia inhibitory factor. This method thus provides the means to investigate the function of neuronal genes and the mechanisms that regulate their transcription in cultured sympathetic neurons. © 2002 Wiley‐Liss, Inc.
γ1 Laminin and its biologically active KDI‐domain may guide axons in the floor plate of human embryonic spinal cord
Authors: Wiksten Markus , Liebkind Ron , Laatikainen Timo , Liesi Päivi
Published: January 2003

Immunocytochemistry, in situ hybridization and Matrigel‐embedded cultures were used to investigate the distribution of laminins during development of the human embryonic spinal cord (7–11 weeks). Our results indicate that α1, β1, β3 and γ1 laminins localize as punctate deposits in the floor plate region in association with commissural fibers crossing the ventral midline. In addition, the neurite outgrowth domain of γ1 laminin accumulates heavily in the floor plate region, in the notochord and in GFAP‐immunoreactive glial fibers of the embryonic spinal cord. In culture experiments, the biologically active KDI‐domain of γ1 laminin selectively attracted directional outgrowth of neurites from explants of the dorsal spinal cord. The spatial and temporal colocalization of punctate deposits of laminins with nerve fibers crossing the ventral midline, and the guidance of neurites by the KDI‐peptide domain, indicate that laminins, specifically the γ1 laminin, may be involved in guidance of axons during embryonic development of the human spinal cord. © 2002 Wiley‐Liss, Inc.
Loss of nicotinic receptors induced by beta‐amyloid peptides in PC12 cells: Possible mechanism involving lipid peroxidation
Authors: Guan Zhi‐Zhong , Yu Wen‐Feng , Shan Ke‐Ren , Nordman Tomas , Olsson Jerker , Nordberg Agneta
Published: January 2003

The mechanisms involved in the loss of nicotinic acetylcholine receptors (nAChRs), seen in brains of patients with Alzheimer's disease (AD) and in cultured cells treated by β‐amyloid peptides (Aβs), remain elusive. We give results to show that lipid peroxidation induced directly by Aβ might be involved in the deficits of nAChRs. In the study, PC12 cells were treated by addition of 5 μM of Aβ25–35 and Aβ1–40, respectively, with or without a antioxidant, vitamin E. Besides significantly decreased MTT (3‐(4,5‐dimethylthiazol‐2‐yl)‐2,5,diphenyltetrazolium bromide) reduction, an increased lipid peroxidation was detected in the cells, but no protein oxidation. Significant reductions in [3H]epibatidine and [125I]α‐bungarotoxin binding sites and in the protein levels of the α3 and α7 nAChR subunits were observed in the cells treated with Aβs. Furthermore, Aβ25–35 decreased the level of ubiquinone‐9 in PC12 cells, but did not change the amount of cholesterol, providing further evidence for lipid peroxidation. Interestingly, when PC12 cells were pretreated by antioxidant before the addition of Aβs, the lipid peroxidation and the decreased ubiquinone resulted from Aβs were prohibited. The decreases of nAChR binding sites and subunit proteins resulted from Aβs were mostly prevented by the pretreatment with antioxidant. These findings suggest that lipid peroxidation stimulated by Aβs might be a mechanism for the loss of nAChRs associated with the pathogenesis of AD. © 2002 Wiley‐Liss, Inc.
Differential expression of L‐ and S‐MAG upon cAMP stimulated differentiation in oligodendroglial cells
Authors: Erb M. , Steck A.J. , Nave K.A. , Schaeren‐Wiemers N.
Published: January 2003

Myelin‐associated glycoprotein (MAG), an immunoglobulin‐like cell signaling protein involved in axon‐glial interactions, displays two intracellular C‐termini as a result of alternative mRNA splicing. During brain development, the two MAG mRNAs that encode L‐MAG and S‐MAG differ in their relative abundance. We have investigated the differential expression of L‐ and S‐MAG upon cAMP treatment in the oligodendroglial cell line Oli‐neu, a cell line able to differentiate in vitro. We have engineered GFP and VSVG fusions by small insertions into the alternatively spliced exons of the cloned MAG gene and reintroduced them into Oli‐neu cells. The individually tagged MAG isoforms were expressed under the control of the MAG promoter and regulatory region. In this system, L‐MAG was the predominant isoform before the stimulation of cells with cAMP, whereas upon cAMP treatment the S‐MAG isoform was predominantly expressed in cells with a high degree of morphological differentiation. We suggest that the regulation of the MAG alternative splicing and the morphological differentiation in oligodendrocytes are controlled both by the same cAMP‐responsive differentiation step. © 2002 Wiley‐Liss, Inc.
Effects of peroxisome proliferator‐activated receptor‐γ agonists on central nervous system inflammation
Authors: Kielian Tammy , Drew Paul D.
Published: January 2003

Peroxisome proliferator‐activated receptor‐γ (PPAR‐γ) plays a critical role in glucose and lipid metabolism. More recently, PPAR‐γ ligands have been reported to inhibit the expression of proinflammatory molecules by monocytes/macrophages. Of relevance to CNS disease is that PPAR‐γ agonists have been demonstrated to have similar effects on microglia. PPAR‐γ agonists also ameliorate experimental autoimmune encephalomyelitis, an animal model of multiple sclerosis. This Mini‐Review summarizes the effects of PPAR‐γ agonists in mediating immune responses and the potential of these agonists in the treatment of inflammatory disorders of the CNS. © 2002 Wiley‐Liss, Inc.
Changes in distribution, cell associations, and protein expression levels of NG2, neurocan, phosphacan, brevican, versican V2, and tenascin‐C during acute to chronic maturation of spinal cord scar tissue
Authors: Tang Xiufeng , Davies Jeannette E. , Davies Stephen J.A.
Published: January 2003

Previous studies have correlated the failure of axon regeneration after spinal cord injury with axons contacting scar tissue rich in chondroitin sulfate proteoglycans (CSPGs; Davies et al., 1999). In the present study, we have conducted immunohistochemical and quantitative Western blot analysis of five axon‐growth‐inhibitory CSPGs and tenascin‐C within stab injuries of adult rat spinal cord at time points ranging from 24 hr to 6 months post injury. Quantitative Western blot analysis showed robust increases in neurocan, tenascin‐C, and NG2 levels by 24 hr, suggesting that these molecules play a role in preventing axon regeneration across acutely forming scar tissue. Peak levels of 245/130 kD neurocan, NG2, and 250/200 kD tenascin‐C were reached at 8 days, with maximum levels of phosphacan and 140/80 kD brevican attained later, at 1 month post injury. Versican V2 protein levels, however, displayed an opposite trend, dropping below unlesioned spinal cord values at all time points studied. Confocal microscopy at 8 days post injury revealed heightened immunoreactivity for phosphacan, NG2, and tenascin‐C, particularly within fibronectin+ scar tissue at lesion centers. In contrast, neurocan was displayed within lesion margins on the processes of stellate NG2+ cells and, to a much lesser extent, by astrocytes. At 6 months post injury, 130 kD neurocan, brevican, and NG2 levels within chronic scar tissue remained significantly above control. Our results show novel expression patterns and cell associations of inhibitory CSPGs and tenascin‐C that have important implications for axon regeneration across acute and chronic spinal cord scar tissue. © 2002 Wiley‐Liss, Inc.
The collaborative historical African rainfall model: description and evaluation
Authors: Funk Chris , Michaelsen Joel , Verdin Jim , Artan Guleid , Husak Greg , Senay Gabriel , Gadain Hussein , Magadazire Tamuka
Published: January 2003

In Africa the variability of rainfall in space and time is high, and the general availability of historical gauge data is low. This makes many food security and hydrologic preparedness activities difficult. In order to help overcome this limitation, we have created the Collaborative Historical African Rainfall Model (CHARM). CHARM combines three sources of information: climatologically aided interpolated (CAI) rainfall grids (monthly/0.5° ), National Centers for Environmental Prediction reanalysis precipitation fields (daily/1.875° ) and orographic enhancement estimates (daily/0.1° ). The first set of weights scales the daily reanalysis precipitation fields to match the gridded CAI monthly rainfall time series. This produces data with a daily/0.5° resolution. A diagnostic model of orographic precipitation, VDELB—based on the dot‐product of the surface wind V and terrain gradient (DEL) and atmospheric buoyancy B—is then used to estimate the precipitation enhancement produced by complex terrain. Although the data are produced on 0.1° grids to facilitate integration with satellite‐based rainfall estimates, the ‘true’ resolution of the data will be less than this value, and varies with station density, topography, and precipitation dynamics. The CHARM is best suited, therefore, to applications that integrate rainfall or rainfall‐driven model results over large regions.

The CHARM time series is compared with three independent datasets: dekadal satellite‐based rainfall estimates across the continent, dekadal interpolated gauge data in Mali, and daily interpolated gauge data in western Kenya. These comparisons suggest reasonable accuracies (standard errors of about half a standard deviation) when data are aggregated to regional scales, even at daily time steps. Thus constrained, numerical weather prediction precipitation fields do a reasonable job of representing large‐scale diurnal variations. Published in 2003 by John Wiley & Sons, Ltd.
A simplified analysis method for piled raft foundations in non‐homogeneous soils
Authors: Kitiyodom Pastsakorn , Matsumoto Tatsunori
Published: January 2003

A simplified method of numerical analysis based on elasticity theory has been developed for the analysis of axially and laterally loaded piled raft foundations embedded in non‐homogeneous soils and incorporated into a computer program “PRAB”. In this method, a hybrid model is employed in which the flexible raft is modelled as thin plates and the piles as elastic beams and the soil is treated as springs. The interactions between structural members, pile–soil–pile, pile–soil–raft and raft–soil–raft interactions, are approximated based on Mindlin's solutions for both vertical and lateral forces with consideration of non‐homogeneous soils. The validity of the proposed method is verified through comparisons with some published solutions for single piles, pile groups and capped pile groups in non‐homogeneous soils. Thereafter, the solutions from this approach for the analysis of axially and laterally loaded 4‐pile pile groups and 4‐pile piled rafts embedded in finite homogeneous and non‐homogeneous soil layers are compared with those from three‐dimensional finite element analysis. Good agreement between the present approach and the more rigorous finite element approach is demonstrated. Copyright © 2002 John Wiley & Sons, Ltd.
A study of the effect of driving on pre‐bored piles
Authors: Mabsout Mounir , Sadek Salah
Published: January 2003

A finite element model for pile‐driving analysis is developed and used to investigate the behaviour of pre‐bored piles, which are then driven the last 1.25 or 2.25 m to their final design depth. The study was conducted for the case of saturated clays. The model traces the penetration of the pile into the soil and accommodates for large deformations. The non‐linear behaviour of the clay in this study is predicted using the bounding‐surface‐plasticity model, as applied to isotropic cohesive soils. The details of the 3‐D numerical modelling and computational schemes are presented. A significant difference was observed in the pile displacement during driving, and in the computed soil resistance at the pile tip, particularly at the earliest driving stages. No difference in soil resistance at the soil pile interface along the pile shaft was detected between the pre‐bored piles whether driven 1.25 or 2.25 m. Copyright © 2002 John Wiley & Sons, Ltd.
The stochastic U‐line balancing problem
Authors: Guerriero Franco , Miltenburg John
Published: January 2003

A U‐line arranges tasks around a U‐shaped production line and organizes them into stations that can cross from one side of the line to the other. In addition to improving visibility and communication between operators on the line, which facilitates problem‐solving and quality improvement, U‐lines can reduce the total number of operators required on the line and make rebalancing the line easier compared to the traditional, straight production line. This paper studies the (type 1) U‐line balancing problem when task completion times are stochastic. Stochastic completion times occur when differences between operators cause completion times to vary somewhat and when machine processing times vary. A recursive algorithm is presented for finding the optimal solution when completion times have any distribution function. An equivalent shortest path network is also presented. An improvement for the special case of normally distributed task completion times is given. A computational study to determine the characteristics of instances that can be solved by the algorithms shows that they are able to solve instances of practical size (like the 114 Japanese and U.S. U‐lines studied in a literature review paper). © 2002 Wiley Periodicals, Inc. Naval Research Logistics, 2003
Block replacement policies for a two‐component system with failure dependence
Authors: Scarf Philip A. , Deara Mohammed
Published: January 2003

Block replacement and modified block replacement policies for two‐component systems with failure dependence and economic dependence are considered in this paper. Opportunistic maintenance policies are also considered. Where tractable, long‐run costs per unit time are calculated using renewal theory based arguments; otherwise simulation studies are carried out. The management implications for the adoption of the various policies are discussed. The usefulness of the results in the paper is illustrated through application to a particular two‐component system. © 2002 Wiley Periodicals, Inc. Naval Research Logistics, 2003