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C Pipan

Publications and source records attributed to C Pipan.

At least 19 recordsLinked to original sources
PubMed2004

Qualitative multiplex RT-PCR for simultaneous detection of hepatitis C virus and human immunodeficiency virus in plasma samples.

This report describes the development of a one-tube multiplex reverse transcriptase (RT)-PCR assay for the simultaneous detection of hepatitis C virus (HCV) and human immunodeficiency virus (HIV) in plasma samples. The assay was evaluated with two panels of HCV- and HIV-1-positive samples, as well as negative plasma specimens. Extraction and amplification of HCV and HIV-1 RNA from plasma samples were performed in a single reaction, and amplified genomes were detected with specific probes. Serial dilutions of the HCV and HIV-1 first World Health Organization International Standards were used to evaluate the sensitivity of the method. Two RNA controls were constructed to determine inter-assay variations and the sensitivity of the amplification step. The assay had good specificity and detected all the genotypes and subtypes tested. The analytical sensitivity of the entire assay was 100 IU/mL for HCV and 200 IU/mL for HIV-1, while the amplification step detected ten copies/reaction for HCV and 20 copies/reaction for HIV-1. The multiplex assay allowed the simultaneous extraction, amplification and detection of two virus genomes, thereby providing an important practical advantage and an efficient approach for analysing individual and pooled plasma donations.

Feasibility Studies↗
PubMed2001

Detection of human papillomavirus DNA and p53 gene mutations in esophageal cancer samples and adjacent normal mucosa.

BACKGROUND/AIM: There is evidence of a possible etiological role of human papillomaviruses (HPVs) in the development of esophageal tumors. Loss of function of the wild-type p53 tumor suppressor gene product by binding to E6 oncoproteins of high-risk HPVs is considered an important event in tumor development. The aim of this study was to verify the prevalence of HPV infection and p53 mutation in esophageal tumor tissue samples and in the adjacent normal mucosa in patients from a high-risk area in Italy. METHODS: DNA from 33 biopsy specimens (17 tumor sample biopsies and 16 samples of adjacent normal mucosa) was screened for HPV DNA using two polymerase chain reaction based procedures. Restriction fragment length polymorphism analysis was used for typing. Screening of p53 mutations was performed with polymerase chain reaction-single strand conformation polymorphism analysis and DNA sequencing. RESULTS: Overall, 8 of 17 patients presented HPV DNA; HPV 16 was detected in 4 of 8 samples. Samples from tumors and adjacent mucosa were positive for mucosal HPVs in 7 of 17 and 4 of 16 cases, respectively. In 1 case, HPV DNA was detected in the normal mucosa only. None of the samples contained HPVs of the epidermodysplasia verruciformis or cutaneous groups. Mutations of p53 were detected in two HPV DNA negative samples. In both cases, the mutation was present in the tumor only. CONCLUSIONS: Our results are in favor of the involvement of both aberrant p53 expression and HPV infection in the development of esophageal tumors. The high HPV infection rate in patients from a high-risk region suggests that subjects harboring HPVs (in particular HPV 16) in the esophagus should be considered at risk of esophageal malignancies.

Adenocarcinoma↗
PubMed1999

PCR-RFLP-detected human papilloma virus infection in a group of senegalese women attending an STD clinic and identification of a new HPV-68 subtype.

Cancer of the cervix is the most common malignant tumor among women in Africa and, in particular, Senegal. Studies of the prevalence of human papilloma virus (HPV) infection in Africa have mainly focused on carcinomas. Data on the presence of the virus in women with normal cervical cytology are scarce. In this study, 158 cytologically normal women who had been referred to the 'Institut Pasteur de Dakar' (Senegal) for various genital complaints were investigated for the presence of HPV on exfoliated cells by PCR-RFLP. HPV was detected in 13.9% of cases. Oncogenic type HPV 16 was the most common type (40.9%), followed by HPV 53 and HPV 58, both detected in 13.6% of cases. Mixed HPV infections were present in 13. 6% of the subjects. Only HPVs belonging to the intermediate-high risk group were detected. These data suggest the need for careful cytological control of patients. A PCR-HPV fragment (GA115) possessing an original RFLP pattern was isolated. After sequencing, it showed a nucleotide homology of 97.1% with HPV 68 and should therefore be considered a new HPV 68 subtype. The use of PCR-RFLP strategy enables detection and typing of all known and as yet unknown genital HPVs. Variant and subtype classification of HPV types identified by oligonucleotide probe methods may need to be refined, especially for less prevalent HPVs and in areas where little information on HPV prevalence is available. More studies are needed to characterize satisfactorily the epidemiology of HPV in Africa.

Adolescent↗
PubMed1998

Development of a PCR microplate-capture hybridization method for simple, fast and sensitive detection of Salmonella serovars in food.

The authors have developed an easy and rapid detection and identification system for Salmonella spp. in food. The gene inv A was selected as the target sequence. Oligonucleotides derived from conserved regions of this gene were able to exclusively prime the amplification of a 389 bp fragment when Salmonella spp. DNA was used as the template. An internal Salmonella spp. specific DNA probe was used for confirmation of the amplified polymerase chain reaction(PCR)product, by Southern blot or microplate-capture hybridization assay. In this fashion the sensitivity of the method was increased 100-fold (4.5 fg total DNA). To validate the method, a total of 75 food samples were tested. The PCR-microplate capture hybridization assay is easy to perform and much faster than traditional detection methods for Salmonella spp. in food. Hybridization in microtitre plates is more readily observed than in Southern blot and is more sensitive than conventional agarose gel electrophoresis.

Biotin↗
PubMed1998

Impact of hepatitis C virus infection on clinical features, quality of life and survival of patients with lymphoplasmacytoid lymphoma/immunocytoma.

BACKGROUND: The non-Hodgkin's lymphoma (NHL) subgroup most frequently associated with hepatitis C virus (HCV) infection is the lymphoplasmacytoid lymphoma/immunocytoma (Lp-Ic). We have assessed the impact of the infection on the clinical features, quality of life and survival of HCV+ve Lp-Ic patients as compared to its impact in HCV-ve patients. PATIENTS AND METHODS: Seventy patients with Lp-Ic consecutively observed over a six-year period were studied. Clinical, virological and histopathological features were recorded at diagnosis. Quality of life was assessed using a scoring system including disease-related symptoms, performance status, working ability, hospital admissions and therapies required. RESULTS: Eighteen patients (26%) with HCV infection were identified. Significant differences between those patients and the HCV-ve group included number of symptomatic patients, Hb levels, serum protein levels, entity of the IgM monoclonal component, number of patients with cryoglobulins and with organ (liver, kidney) involvement, and entity and pattern of bone marrow infiltration. Survival rates were similar (P = 0.8383), but the quality-of-life score was significantly worse for the HCV+ve patients (P = 0.002). All anti-HCV Ab+ve patients tested positive for HCV RNA; genotype 2ac was detected in a significant proportion of cases. CONCLUSIONS: This study confirms that HCV infection is present in about one-third of patients with Lp-Ic. HCV infection does not seem to affect the overall survival of patients with Lp-Ic, but it affects the clinical expression of the disease, so that the overall quality of life of HCV+ve patients is significantly worse.

Adult↗
PubMed1997

Chronic hepatitis C virus infection after treatment for pediatric malignancy.

Sera of 658 patients who had completed treatment for pediatric malignancy were analyzed by a second-generation enzyme-linked immunosorbent assay and recombinant immunoblot assay test to assess the prevalence of hepatitis C virus (HCV)-seropositivity. All HCV-seropositive patients underwent detailed clinical, laboratory, virologic, and histologic study to analyze the course of HCV infection. One hundred seventeen of the 658 patients (17.8%) were positive for HCV infection markers. Among the 117 anti-HCV+ patients, 41 (35%) were also positive for markers of hepatitis B virus infection with or without delta virus infection markers, 91 (77.8%) had previously received blood product transfusions, and 25 (21.4%) showed a normal alanine aminotransferase (ALT) level during the last 5-year follow-up (11 of them never had abnormal ALT levels). The remaining 92 patients showed ALT levels higher than the upper limit of normal range. Eighty-one of 117 (70%) anti-HCV+ patients were HCV-RNA+, with genotype 1b being present in most patients (54%). In univariate analysis, no risk factor for chronic liver disease was statistically significant. In this study, the prevalence of HCV infection was high in patients who were treated for a childhood malignancy. In about 20% of anti-HCV+ patients, routes other than blood transfusions are to be considered in the epidemiology of HCV infection. After a 14-year median follow-up, chronic liver disease of anti-HCV+ positive patients did not show progression to liver failure.

Adolescent↗
PubMed1997

Single-strand conformation polymorphism (SSCP) analysis of Listeria monocytogenes iap gene as tool to detect different serogroups.

PCR-single-strand conformation polymorphism (PCR-SSCP) analysis is a convenient technique for the detection of mutations. As the mobility of single-stranded DNA is sequence-dependent it could therefore be used to determine serotype-related sequence variations in Listeria monocytogenes. Sero-specific patterns were observed in different L. monocytogenes serogroups.

Bacterial Proteins↗
PubMed1997

Characterization of a putative new HPV genomic sequence from a cervical lesion using L1 consensus primers and restriction fragment length polymorphism.

Various methods have been proposed for HPV detection and typing. Prevalence and distribution among types have varied depending upon the methods used and the populations studied. We have applied the polymerase chain reaction (PCR) followed by a Restriction Fragment Length Polymorphism (RFLP) analysis using the MY09/MY11 primers for detection of HPV in cervicovaginal lavages obtained from 323 patients who were referred to our Clinical Department either for genital complaints or an abnormal PAP smear. We assessed (i) the prevalence of HPV and (ii) the reliability of RFLP-typing. For the latter, 35 PCR-HPV products were sequenced. HPV-DNA was detected in 40/197 (20.3%) patients with normal cytology 86/111 (77.5%) with LSIL and 11/15 (73.3%) with HSIL. HPV-16 was the most common type detected in normal cervical cytology samples (10/40, 25%), whereas HPV 16 and 18 were detected in 36/97 (37.1%) of the LSIL and HSIL patients, evidencing the presence of these high-risk HPV types not only in malignant conditions. Results obtained after partial nucleotide sequencing confirmed the results obtained by RFLP analysis. In this study, a putative new HPV fragment (GA6053) was identified. Its closest homology to other known HPV types is 73.8% to HPV-62, 73.0% to HPV-61 and 67.7% to HPV-18. The use of degenerate primers, in conjunction with RFLP, proved to be a reliable method for HPV detection and typing.

Adolescent↗
PubMed1997

The genotype of the hepatitis C virus in patients with HCV-related B cell non-Hodgkin's lymphoma.

Increasing evidence suggests that the hepatitis C virus (HCV) might be involved in the pathogenesis of B cell non-Hodgkin's lymphomas (NHL). Since several HCV genotypes are currently identifiable and might be involved in the pathogenesis of different diseases (with different severity and responsiveness to therapy), the aim of our study was to assess the prevalence of viral genotypes in a group of patients with HCV-related NHL. Among 470 consecutive patients, 42 HCV Ab-positive cases were identified. HCV RNA could be detected by reverse transcriptase-polymerase chain reaction and genotyping performed in 31 of these cases. As compared to our control group (211 healthy blood donors and patients with chronic liver disease), a striking high prevalence of genotype 2ac was detected among B cell NHL (48.4 vs 9.0%), with a relative risk of infection of 5.37 (P < 0.0001). No major differences were observed in the distribution of NHL histotypes and in the clinical features among patients with genotype 1b (the other most frequent genotype) or 2ac, a part from a trend towards a higher percentage of liver disease and a lower likelihood of response to interferon for patients with genotype 1b. The same high prevalence of genotype 2ac has been recently reported in patients with mixed cryoglobulinemia (MC), monoclonal gammopathies, B cell NHL complicating MC and autoimmune hepatitis. All these data taken together suggest that genotype 2ac might be involved in the pathogenesis of lymphoproliferative and autoimmune disorders.

Adult↗
PubMed1996

Prevalence of hepatitis C virus infection in patients with lymphoproliferative disorders.

It has been recently hypothesized that the hepatitis C virus (HCV) might be involved in the pathogenesis of malignant B-cell non-Hodgkin's lymphomas (NHL). On the basis of this observation we sought to determine the prevalence of HCV infection in the patients affected by B-cell NHL and extended our analysis to all the patients affected by lymphoproliferation disorders seen at our institution in the last 30 months. Five hundred and thirty-seven unselected, consecutive patients were studied. HCV infection was investigated through detection of anti-HCV antibodies and HCV-RNA. HCV genotyping was performed on HCV-RNA positive specimens. The risk of being infected by HCV was compared with that of the general population of our area. Among all lymphoproliferative disorders, the prevalence and the relative risk (RR) of being infected by HCV were increased only among B-cell NHL (9%; RR 3.24; p < .0001). Among these, a strong prevalence of HCV was found only in the subgroup of immunocytomas (30%; RR 10.27; P < .0001), while other histotypes were associated with it only occasionally. Because HCV-positive lymphomas clinically behave as essential mixed cryoglobulinemia (EMC), the close association between HCV infection and EMC is confirmed, and evidence is provided that the pathological substrate of EMC corresponds to the immunocytoma. HCV genomic sequences were found in 84% of patients analyzed. Viral genotypes were those more frequent in our area.

Adult↗
PubMed1996

Vertical transmission of hepatitis C virus in low-risk pregnant women.

To assess the prevalence of hepatitis C virus (HCV) infection in pregnant women and the rate of vertical transmission in infected mothers belonging to a low-risk group, 1,388 women were tested for HCV antibody at delivery. Twenty-five anti-HCV-positive women with no apparent source of HCV exposure were recruited. A reverse transcriptase-polymerase chain reaction (RT-PCR) and a new quantitative branched DNA-based signal amplification assay (bDNA) were used to detect HCV RNA. The rate of anti-HCV positivity in pregnant women was 2.5% (36 of 1,388). Of the 25 cohort mothers, 18 (72%) were positive for HCV RNA by RT-PCR, 13 of whom were also positive by the bDNA assay (sensitivity 72.2%). Of the 25 infants of low-risk mothers tested at birth, 22 were anti-HCV positive, two were weakly reactive, one was negative, and none was viremic. Neither active humoral immunoresponse nor HCV RNA was detected in any of the infants over a period of 12 months. These data suggest a relatively high prevalence of anti-HCV in unselected pregnant women and a poor efficiency of vertical transmission of HCV in a low-risk population, irrespective of the viral burden of the mother-to-be.

Adult↗
PubMed1996

A combined polymerase chain reaction and restriction endonuclease enzyme assay for discriminating between Campylobacter coli and Campylobacter jejuni.

A combined polymerase chain reaction and restriction endonuclease (RE) enzyme assay was developed to discriminate between Campylobacter coli and Campylobacter jejuni. Amplimers of the FlaA gene obtained by PCR were digested with AluI and HinfI to distinguish C. coli from C. jejuni. With AluI digestion C. jejuni-specific bands were observed at 110, 140 and 160 bp and C. coli-specific bands at 293 and 147 bp. C. jejuni-specific bands of 349 and 109 bp were found by HinfI digestion but HinfI did not digest the FlaA amplimer of C. coli. This combined technique is fast and easy to perform, and distinguishes the two campylobacters unequivocally.

Campylobacter coli↗
PubMed1995

Detection of HPV-DNA in semen, urine and urethral samples by dot blot and PCR.

Papillomavirus infection in women is associated with the development of carcinoma or squamous intraepithelial lesions (SIL). Limited information is available for men. Seventy asymptomatic male partners of HPV-DNA positive women were studied. Exfoliated cells collected using urethral swabs urine and semen were examined for HPV-DNA using Dot blot and PCR. On exfoliated cells collected using a urethral swab, 89% of the samples were inadequate on Dot blot, and 87% on PCR respectively. Using urine, 36% turned out to be inadequate on Dot blot, 21% on PCR. Using semen all of the 70 samples were satisfactory for both systems. Semen is thus the best material for analysis. The occurrence of HPV-DNA in urine in urine is less frequent than that in semen. Urethral swabs seem to represent the least reliable material. Carriage of human papillomaviruses is frequent in apparently healthy parternrs of HPV infected women.

Cohort Studies↗
PubMed1995

Polymerase chain reaction assay for detection of Campylobacter coli and Campylobacter jejuni in poultry meat.

Primers of 16S rRNA and flaA genes were used to optimise a PCR technique for detecting thermotolerant campylobacters in poultry meat. Different methods for crude DNA extraction were also evaluated. The use of flaA primers and extraction of nucleic acid by boiling and proteinase K gave good results in the detection of Campylobacter either in artificially or naturally contaminated foodstuffs. The lowest sensitivity limit for the PCR reaction was 10(1)-10(2) thermophilic Campylobacter cells either in pure cultures or in artificially and naturally contaminated poultry skins, corresponding to a concentration of 10(2)-10(3) Campylobacter/ml or g product. The PCR method we devised had a high sensitivity and specificity. It appears to give better results than conventional methods and is very easy and fast, requiring only eight hours to detect thermotolerant Campylobacter from poultry meat. In contrast, conventional methods require almost 4 days.

Animals↗