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1.
Surg Oncol ; 34: 223-233, 2020 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-32869748

RESUMEN

INTRODUCTION: The current Tumor Node Metastasis staging system (TNM) for gastric cancer classifies the extent of lymph node metastasis based upon the number of lymph nodes involved. Choi et al. have recently proposed a new anatomical classification based upon the regionality of the involved nodes. This new classification seems to have a better predictive prognostic value than the traditional one. We investigated the prognostic role of the new anatomical based classification, reviewing our institutional gastric cancer database. METHODS: We performed a retrospective chart review of 329 patients who underwent gastrectomy at our Institution from 2003 to 2017. We excluded from data analysis any patient with distant metastases at the time of first diagnosis and or surgery, pathology other than adenocarcinoma, lymphadenectomy less than D2, impossibility to identify location of lymph nodes (LNs) on pathological report and neoadjuvant chemotherapy. The extent of D2 lymphadenectomy was defined according to Japanese Gastric Cancer Association criteria. LN metastasis were reclassified into three topographic groups (lesser, greater curvature, and extraperigastric nodes) and staged according to Choi. The new N stage was combined with the current pT according to the 8th edition of TNM and a new hybrid TNM stage was established. All patients were followed up until June 2019. The prognostic performance of the new stage and of the current anatomical numeric based system (TNM) was analyzed and assessed by the C-index, AIC and likelihood ratio χ2 value. RESULTS: In predicting both Overall Survival (OS) and Disease free Survival (DFS) the new N stage and the new TNM staging system had the highest C-index and likelihood ratio χ2 value and the lowest Akaike Information Criterion (AIC), showing a better accuracy and displaying a better prognostic performance. CONCLUSIONS: Our study is the first from the Western world to compare the new hybrid classification, based on the anatomical location of metastatic nodes, to the 8th of American Joint Committee on Cancer (AJCC) TNM staging system. Our findings on a small, monocentric sample suggest that hybrid topographic lymph node staging system is more accurate than TNM.


Asunto(s)
Gastrectomía/mortalidad , Escisión del Ganglio Linfático/mortalidad , Ganglios Linfáticos/patología , Neoplasias Gástricas/patología , Anciano , Femenino , Estudios de Seguimiento , Humanos , Ganglios Linfáticos/cirugía , Metástasis Linfática , Masculino , Estadificación de Neoplasias , Valor Predictivo de las Pruebas , Estudios Retrospectivos , Neoplasias Gástricas/clasificación , Neoplasias Gástricas/cirugía , Tasa de Supervivencia
2.
Infect Genet Evol ; 76: 104063, 2019 12.
Artículo en Inglés | MEDLINE | ID: mdl-31618693

RESUMEN

In the last years, Matrix Assisted Laser Desorption Ionization Time of Flight Mass Spectrometry gained the attribute of gold-standard method for microbial identification. A rich scientific literature has been produced to evalutate its performance in gram-positive, gram-negative, anaerobic bacteria, and also difficult and exigent pathogens identification, included mycobacteria, yeasts, and molds. Typing in PubMed "MALDI-TOF mass spectrometry" at the date of August 1st 2019, about 14.468 articles can be found. Typing "MALDI-TOF identification" or "MALDI-TOF and microbiology" or "MALDI-TOF and infection" the number of artcicles is reduced to 5747, 3720 and 1746, respectively. In this review, an update of the most important findings reported during last ten years has been provided, confirming the central role of this technology in microbiology.


Asunto(s)
Bacterias/aislamiento & purificación , Hongos/aislamiento & purificación , Infecciones/diagnóstico , Virus/aislamiento & purificación , Bacterias/clasificación , Análisis por Conglomerados , Farmacorresistencia Microbiana , Hongos/clasificación , Humanos , Espectrometría de Masa por Láser de Matriz Asistida de Ionización Desorción , Virus/clasificación
3.
Public Health ; 163: 16-19, 2018 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-30031836

RESUMEN

OBJECTIVES: The management of infectious outbreaks in closed settings represents an important public health issue. An outbreak of acute febrile syndrome affecting 22 refugees resident at the Asylum Seekers Centre of Castelnuovo di Porto in Rome has been reported, and the preventive and control measures adopted have been described as an example of public health safety. METHODS: Pharyngeal swab and whole-blood samples were collected from 22 cases observed and analyzed for standard bacterial cultures and respiratory and herpesviruses by qualitative CLART PneumoVir2 and Entherpex microarray. RESULTS: A possible respiratory-transmitted etiology and a concomitant reactivation of multiple herpesviruses have been evidenced. The epidemiological investigation showed that the spread of the epidemic was promoted because patients were hosted in neighboring rooms or in the same room, facilitating the rapid spread of infectious disease. CONCLUSIONS: The potential way of transmission was supposed, and preventive measures for infection control were adopted. The measures adopted are an example of best practice for outbreak management, and the microbiological surveillance is recommended for public health improvement.


Asunto(s)
Brotes de Enfermedades , Fiebre/epidemiología , Refugiados , Enfermedad Aguda , Adolescente , Adulto , Brotes de Enfermedades/prevención & control , Femenino , Humanos , Italia/epidemiología , Masculino , Refugiados/estadística & datos numéricos , Adulto Joven
4.
J Viral Hepat ; 24(7): 551-560, 2017 07.
Artículo en Inglés | MEDLINE | ID: mdl-28092412

RESUMEN

The extensive genetic heterogeneity of hepatitis C virus (HCV) requires in-depth understanding of the population dynamics of different viral subtypes for more effective control of epidemic outbreaks. We analysed HCV sequences data from 125 participants in Wuhan, China. These participants were newly infected by subtype 1b (n=13), 3a (n=15), 3b (n=50) and 6a (n=39) while on methadone maintenance treatment (MMT). Bayesian phylogenies and demographic histories were inferred for these subtypes. Participants infected with HCV-1b and 3a were clustered in well-supported monophyletic clades, indicating local subepidemics. Subtypes 3b and 6a strains were intermixed with other Chinese isolates, as well as isolates from other Asian countries, reflecting ongoing across geographic boundary transmissions. Subtypes 1b and 3a declined continuously during the past ten years, consistent with the health and economic reform in China, while subtype 3b showed ongoing exponential growth and 6a was characterized by several epidemic waves, possibly related to the recently growing number of travellers between China and other Asian countries. In conclusion, results of this study suggest that HCV subtype 3b and 6a subepidemics in China are currently not under control, and new epidemic waves may emerge given the rapid increase in international travelling following substantial economic growth.


Asunto(s)
Analgésicos Opioides/administración & dosificación , Hepacivirus/clasificación , Hepatitis C/virología , Metadona/administración & dosificación , Tratamiento de Sustitución de Opiáceos/métodos , Dinámica Poblacional , Abuso de Sustancias por Vía Intravenosa/tratamiento farmacológico , Adulto , China/epidemiología , Femenino , Genotipo , Hepacivirus/genética , Hepacivirus/aislamiento & purificación , Hepatitis C/complicaciones , Hepatitis C/epidemiología , Humanos , Masculino , Persona de Mediana Edad , Epidemiología Molecular , Filogenia , Abuso de Sustancias por Vía Intravenosa/complicaciones
5.
BMC Infect Dis ; 12 Suppl 2: S9, 2012.
Artículo en Inglés | MEDLINE | ID: mdl-23173812

RESUMEN

The SINERGIE (South Italian Network for Rational Guidelines and International Epidemiology) project is intended to set up a collaborative network comprising virologists, clinicians and public health officials dealing with patients affected by HCV disease in the Calabria Region. A prospective observational data-base of HCV infection will be developed and used for studies on HCV natural history, response to treatment, pharmaco-economics, disease complications, and HCV epidemiology (including phylogenetic analysis). With this approach, we aim at improving the identification and care of patients, focusing on upcoming research questions. The final objective is to assist in improving care delivery and inform Public Health Authorities on how to optimize resource allocation in this area.


Asunto(s)
Hepatitis C/epidemiología , Hepatitis C/prevención & control , Bases de Datos Factuales , Directrices para la Planificación en Salud , Hepatitis C/tratamiento farmacológico , Humanos , Italia/epidemiología , Salud Pública
6.
AIDS Res Hum Retroviruses ; 25(2): 157-64, 2009 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-19108689

RESUMEN

An increase in the circulation of HIV-1 non-B subtypes has been observed in recent years in Western European countries. Due to the lack of data on the circulation of HIV-1 non-B subtypes among European HIV-1-infected men who have sex with men (MSM), a biomolecular study was conducted in Rome, Italy. HIV-1 partial pol gene sequences from 111 MSM individuals (76 drug naive and 35 drug experienced) were collected during the years 2004-2006. All these sequences were analyzed using the REGA HIV-1 Subtyping Tool, and aligned using CLUSTAL X followed by manual editing using the Bioedit software. A BLAST search for non-B subtype sequences was also performed. Twenty-six (23.4%) MSM were not Italians. Eight individuals (7.2%) were diagnosed as HIV infected before 1991, 20 (18.0%) between 1991 and 1999, and 83 (74.8%) from 2000 to 2006. Fifteen (15/111, 13.5%) individuals were infected with the non-B subtype. The percentage of infection with HIV-1 non-B subtypes was 8.2% (7/85) among Italian MSM and 30.8% (8/26) among the non-Italians (OR = 4.95 95% IC: 1.40-17.87). Individuals infected with the non-B subtype were significantly younger than those infected with the HIV-1 B subtype (28 years vs. 34 years, p = 0.003). The CRFs were more prevalent (8.1%) than pure subtypes (5.4%), which were distributed as follows: subtype C (2.6%), subtype A1 (1.7%), and subtype F1 (0.9%). Major mutations conferring resistance to antiretroviral drugs (ARV) were not found among HIV-1 non-B subtype drug-naive patients but were found in two ARV-experienced individuals. The data show that viral diversity is likely increasing in a population group that had been previously characterized by the circulation of HIV-1 subtype B.


Asunto(s)
Infecciones por VIH/epidemiología , Infecciones por VIH/virología , VIH-1/clasificación , VIH-1/genética , Adulto , Análisis por Conglomerados , Genotipo , Homosexualidad , Humanos , Masculino , Epidemiología Molecular , Datos de Secuencia Molecular , Prevalencia , Ciudad de Roma/epidemiología , Análisis de Secuencia de ADN , Homología de Secuencia , Adulto Joven , Productos del Gen pol del Virus de la Inmunodeficiencia Humana/genética
7.
J Med Virol ; 79(12): 1935-42, 2007 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-17935190

RESUMEN

The human respiratory syncytial virus (HRSV) is the most important cause of admission to hospital for acute lower respiratory tract infections in infants and young children worldwide. Only few studies have investigated the molecular evolution of HRSV, and none has been conduct ed in Italy. The genetic diversity of the G glycoprotein of 59 subgroup A strains obtained from two clinical centers located in Northern and Central Italy was studied, during seven nonconsecutive epidemic seasons (1997-2006). The nucleotide sequences encompassing 624 bp, at the carboxy terminus of the G glycoprotein gene, were compared to sequences representative of previously defined HRSV genotypes. Phylogenetic analysis indicated that most Italian group A isolates clustered into two different lineages (GA2 and GA5), whereas only few isolates grouped into the other known lineages. Eight positively selected sites were found and it was predicted that serine and threonine of positively selected sites 117 and 262 (respectively) are O-glycosilated. The presence of multiple identical sequences in three lineages (GA1, GA5, and BE/A1) suggests that certain strains are predominant in a given epidemic season. Although most of the sites of the G glycoprotein gene of HRSV-A strains seem invariable because of strong purifying selection, some evolutionary "hot spots" may be present. Since the G glycoprotein is a major target (together with the F glycoprotein) of the HRSV humoral immune response, it is important to provide information about its genetic heterogeneity in order to address better both therapeutic and vaccine strategy.


Asunto(s)
Brotes de Enfermedades , Infecciones por Virus Sincitial Respiratorio/virología , Virus Sincitial Respiratorio Humano/genética , Proteínas Virales de Fusión/química , Proteínas Virales de Fusión/genética , Secuencia de Aminoácidos , Humanos , Italia/epidemiología , Mutación , Filogenia , Infecciones por Virus Sincitial Respiratorio/epidemiología , Virus Sincitial Respiratorio Humano/metabolismo , Factores de Tiempo
8.
Infect Agent Cancer ; 1: 4, 2006 Sep 19.
Artículo en Inglés | MEDLINE | ID: mdl-17150133

RESUMEN

Genetic and phylogenetic information on the HIV-1 epidemic in Middle-East Countries, and in particular in Iran, are extremely limited. By March 2004, the Iranian Ministry of Health officially reported a cumulative number of 6'532 HIV positive individuals and 214 AIDS cases in the Iranian HIV-1 epidemic. The intra-venous drug users (IDUs) represent the group at highest risk for HIV-1 infection in Iran, accounting for almost 63% of all HIV-infected population. In this regards, a molecular phylogenetic study has been performed on a sentinel cohort of HIV-1 seropositive IDUs enrolled at the end of 2005 at the University of Mashhad, the largest city North East of Tehran. The study has been performed on both gag and env subgenomic regions amplified by Polymerase Chain Reaction (PCR) from peripheral blood mononuclear cells (PBMCs) and characterized by direct DNA sequence analysis. The results reported here show that the HIV-1 subtype A is circulating in this IDUs sentinel cohort. Moreover, the single phylogenetic cluster as well as the intra-group low nucleotide divergence is indicative of a recent outbreak. Unexpectedly, the Iranian samples appear to be phylogenetically derived from African Sub-Saharan subtype A viruses, raising stirring speculations on HIV-1 introduction into the IDUs epidemic in Mashhad. This sentinel study could represent the starting point for a wider molecular survey of the HIV-1 epidemics in Iran to evaluate in detail the distribution of genetic subtypes and possible natural drug-resistant variants, which are extremely helpful information to design diagnostic and therapeutic strategies.

10.
J Viral Hepat ; 9(6): 460-5, 2002 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-12431210

RESUMEN

Travel to endemic areas is one of the most frequently reported risk factors for infection with the hepatitis A virus (HAV). We evaluated the association between HAV infection and travel, by area of destination. We conducted a case-control study on all cases of HAV infection reported to the Italian National Surveillance System for Acute Viral Hepatitis in the period 1996-2000. The study population consisted of 9695 persons with HAV infection (cases) and 2590 with HBV infection (controls). The risk of acquiring HAV was highest for travel to Asia, Africa and Latin America [Odds Ratio = 9.30 (95%CI = 6.71-12.9)]; a three-fold statistically significant excess of risk was found for travel to southern Italy (OR = 3.03) and to the Mediterranean Area and Eastern Europe (OR = 3.15). Travel was implicated in 28% of the cases of HAV infection. When stratifying the analysis by area of residence (northern and central Italy vs southern Italy and the Islands), the above-mentioned risks were confirmed only for those residing in northern and central Italy, with no significant risk for those residing in southern Italy and the Islands. Travel to areas endemic for HAV infection constitutes a considerable risk. Our results highlight the importance of developing health policies for improving environmental and hygienic conditions, as well as the prevention of certain eating habits. Vaccination before travelling to a medium or high endemic area could be a safe and effective means of preventing travel-related HAV infection.


Asunto(s)
Hepatitis A/epidemiología , Vigilancia de la Población , Viaje , Adolescente , Adulto , Distribución por Edad , Estudios de Casos y Controles , Niño , Preescolar , Demografía , Femenino , Humanos , Lactante , Recién Nacido , Italia , Masculino , Persona de Mediana Edad , Oportunidad Relativa , Factores de Riesgo
11.
J. viral hepat ; 9(6): 460-465, 2002.
Artículo en Inglés | Coleciona SUS | ID: biblio-945252

RESUMEN

Travel to endemic areas is one of the most frequently reported risk factors for infection with the hepatitis A virus (HAV). We evaluated the association between HAV infection and travel, by area of destination. We conducted a case-control study on all cases of HAV infection reported to the Italian National Surveillance System for Acute Viral Hepatitis in the period 1996-2000. The study population consisted of 9695 persons with HAV infection (cases) and 2590 with HBV infection (controls). The risk of acquiring HAV was highest for travel to Asia, Africa and Latin America [Odds Ratio = 9.30 (95%CI = 6.71-12.9)]; a three-fold statistically significant excess of risk was found for travel to southern Italy (OR = 3.03) and to the Mediterranean Area and Eastern Europe (OR = 3.15). Travel was implicated in 28% of the cases of HAV infection. When stratifying the analysis by area of residence (northern and central Italy vs southern Italy and the Islands), the above-mentioned risks were confirmed only for those residing in northern and central Italy, with no significant risk for those residing in southern Italy and the Islands. Travel to areas endemic for HAV infection constitutes a considerable risk. Our results highlight the importance of developing health policies for improving environmental and hygienic conditions, as well as the prevention of certain eating habits. Vaccination before travelling to a medium or high endemic area could be a safe and effective means of preventing travel-related HAV infection


Asunto(s)
Humanos , Niño , Adolescente , Adulto , Epidemiología , Hepatitis A , Factores de Riesgo , Control Sanitario de Viajeros
12.
J Food Prot ; 64(6): 877-80, 2001 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-11403143

RESUMEN

In Italy, the consumption of raw or slightly cooked mussels represents the most important risk factor for the transmission of hepatitis A virus (HAV). Although there exist effective methods for the bacterial depuration of contaminated mussels, these methods are poorly effective on enteric viruses. The objective of the present study was to evaluate the effectiveness of a closed-circuit depuration system that uses both ozone and UV light for disinfecting water and that allows salinity and temperature, important parameters for the metabolism of mussels (Mytilus galloprovincialis), to be maintained at constant levels. The results showed that this depuration method decreased the viral load (from 1.72 log 50% tissue culture infective dose [TCID50] ml(-1) to <1 log TCID50 ml(-1) within 24 h and from 3.82 log TCID50 ml(-1) to <1 log TCID50 ml(-1) within 48 h). However, in both cases, after 120 h of depuration, a residual amount of virus capable of replicating in cells was detected. These results show that depuration, even if performed with advanced systems, may not guarantee the absence of virus.


Asunto(s)
Bivalvos/virología , Microbiología de Alimentos , Hepatitis A/transmisión , Hepatovirus/crecimiento & desarrollo , Animales , Ozono/farmacología , Factores de Tiempo , Rayos Ultravioleta , Carga Viral
13.
Dig Liver Dis ; 33(9): 778-84, 2001 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-11838613

RESUMEN

BACKGROUND: In 1991, compulsory hepatitis B virus vaccination and screening for anti-hepatitis C virus of blood banks were introduced in Italy. AIM: To evaluate the impact of preventive measures on the incidence and risk factors for parenterally transmitted viral hepatitis. METHODS: Data from the surveillance system for acute viral hepatitis for the period 1985-99 were used. Temporal trends in distribution of reported risk factors were analysed by comparing three-year periods: 1987-89 and 1997-99. RESULTS: The incidence (no. cases per 100,000 population) of hepatitis B was 12 in 1985 and 3 in 1999; the incidence of hepatitis non-A, non-B decreased from 5 to 1 in the same period. These decreases were more evident among young adults and before rather than after 1991. Multiple sexual partners, other parenteral exposures and dental treatment remain the most common risk factors for parenterally transmitted viral hepatitis. An increase in frequency over time was observed for other parenteral exposures, whereas a marked decrease was evident for blood transfusion and household contact with an HB-sAg carrier. Invasive medical procedures continue to represent an important source of infection. Intravenous drug use was reported particularly by young adults with non-A, non-B hepatitis, with increased frequency over time. CONCLUSIONS: Non-immunologic measures for preventing hepatitis B and non-A, non B due to iatrogenic and other parenteral exposures, combined with hepatitis B virus vaccination, could further reduce parenteral transmission.


Asunto(s)
Hepatitis Viral Humana/epidemiología , Enfermedad Aguda , Adolescente , Adulto , Transfusión Sanguínea , Niño , Preescolar , Femenino , Hepatitis Viral Humana/transmisión , Humanos , Incidencia , Lactante , Italia/epidemiología , Masculino , Vigilancia de la Población , Factores de Riesgo , Conducta Sexual , Abuso de Sustancias por Vía Intravenosa
14.
Dig. liver dis ; 33(9): 778-784, 2001.
Artículo en Inglés | Coleciona SUS | ID: biblio-945022

RESUMEN

BACKGROUND: In 1991, compulsory hepatitis B virus vaccination and screening for anti-hepatitis C virus of blood banks were introduced in Italy.AIM: To evaluate the impact of preventive measures on the incidence and risk factors for parenterally transmitted viral hepatitis.METHODS: Data from the surveillance system for acute viral hepatitis for the period 1985-99 were used. Temporal trends in distribution of reported risk factors were analysed by comparing three-year periods: 1987-89 and 1997-99. RESULTS: The incidence (no. cases per 100,000 population) of hepatitis B was 12 in 1985 and 3 in 1999; the incidence of hepatitis non-A, non-B decreased from 5 to 1 in the same period. These decreases were more evident among young adults and before rather than after 1991. Multiple sexual partners, other parenteral exposures and dental treatment remain the most common risk factors for parenterally transmitted viral hepatitis. An increase in frequency over time was observed for other parenteral exposures, whereas a marked decrease was evident for blood transfusion and household contact with an HB-sAg carrier. Invasive medical procedures continue to represent an important source of infection. Intravenous drug use was reported particularly by young adults with non-A, non-B hepatitis, with increased frequency over time. CONCLUSIONS: Non-immunologic measures for preventing hepatitis B and non-A, non B due to iatrogenic and other parenteral exposures, combined with hepatitis B virus vaccination, could further reduce parenteral transmission


Asunto(s)
Masculino , Femenino , Humanos , Preescolar , Niño , Adolescente , Adulto , Enfermedad Aguda , Transfusión Sanguínea , Hepatitis Viral Humana/epidemiología , Hepatitis Viral Humana/transmisión , Italia/epidemiología , Vigilancia de la Población , Factores de Riesgo , Conducta Sexual , Abuso de Sustancias por Vía Intravenosa
15.
J Hepatol ; 33(6): 980-5, 2000 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-11131462

RESUMEN

BACKGROUND/AIMS: This study aimed to evaluate the impact of the campaign for hepatitis B mass immunisation of children and teenagers, introduced in 1991, on the incidence of and risk factors for hepatitis B in Italy. METHODS: Hepatitis B cases reported to the surveillance system for type-specific acute viral hepatitis (SEIEVA) during the period 1987-1997 were used to estimate incidence. To assess the association between potential risk factors and hepatitis B cases, hepatitis A cases generated by the same surveillance system were used as controls. RESULTS: During the period 1987-1997, 8275 acute hepatitis B cases were reported to SEIEVA. Hepatitis B incidence declined from 10.4/100,000 in 1987 to 2.9/100,000 in 1997. The fall was more evident before than after the introduction of compulsory vaccination against hepatitis B. The results of multivariate analysis showed that during the years 1995-1997, blood transfusion, intravenous drug use, surgical intervention, dental therapy, other parenteral exposures, multiple sexual partners, and being in the household of a chronic HBsAg carrier were all exposures independently associated with hepatitis B. CONCLUSIONS: The strong association linking acute hepatitis B with iatrogenic exposures, which are more common in adults, suggests that the present immunisation strategy should be combined with the implementation of non-immunologic preventive measures.


Asunto(s)
Hepatitis B/epidemiología , Hepatitis B/prevención & control , Vacunación , Enfermedad Aguda , Adolescente , Adulto , Niño , Preescolar , Femenino , Hepatitis B/transmisión , Humanos , Incidencia , Lactante , Recién Nacido , Italia , Masculino , Factores de Riesgo
16.
J Appl Microbiol ; 87(6): 884-8, 1999 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-10664911

RESUMEN

Hepatitis A is a widespread infectious disease world-wide. In Italy, shellfish consumption was shown to be a major risk factor for hepatitis A infection, especially when these products are eaten raw or slightly cooked. The aim of the present study was to evaluate Hepatitis A virus (HAV) resistance in experimentally contaminated mussels treated at different temperatures (60, 80 and 100 degrees C) for various times. The presence of HAV was evaluated by cell culture infection and reverse transcriptase-polymerase chain reaction confirmation. The experiments, carried out on HAV suspension and contaminated mussel homogenate both containing about 10(5) 50% tissue culture infectious dose ml-1, showed that, under our experimental conditions, the treatments at 60 degrees C for 30 min, 80 degrees C for 10 min and an immersion at 100 degrees C for 1 min were not sufficient to inactivate all the viruses; it was necessary to prolong the treatment at 100 degrees C for 2 min to completely inactivate the virus. Thus it is advisable to eat only cooked shellfish, paying particular attention to the times and temperatures used in the cooking process, since evidence suggests that the shellfish body may protect the virus from the heat effect.


Asunto(s)
Bivalvos/virología , Microbiología de Alimentos , Hepatovirus/crecimiento & desarrollo , Mariscos/virología , Animales , Calefacción , Reacción en Cadena de la Polimerasa de Transcriptasa Inversa
18.
Appl Environ Microbiol ; 63(10): 4102-6, 1997 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-9327577

RESUMEN

The purpose of this study was to characterize strains of Vibrio cholerae non-O1 isolated in Italy from different sources by biochemical and serological assays, antibiotic susceptibility testing, and molecular biotyping. Serotyping and genomic analysis by pulsed-field gel electrophoresis proved to be useful in discriminating the isolates. The data obtained show a wide heterogeneity at the genomic level, and in keeping with this, the serogrouping classification provided evidence of a high variability of the investigated strains. In addition, none of the strains tested produced cholera-like toxins.


Asunto(s)
Vibrio cholerae/clasificación , Vibrio cholerae/genética , Animales , Técnicas de Tipificación Bacteriana , Toxina del Cólera/genética , ADN Bacteriano/genética , ADN Bacteriano/aislamiento & purificación , Farmacorresistencia Microbiana , Electroforesis en Gel de Campo Pulsado , Microbiología Ambiental , Genes Bacterianos , Genotipo , Humanos , Italia , Fenotipo , Serotipificación , Vibrio cholerae/aislamiento & purificación
19.
Infect Immun ; 64(2): 466-71, 1996 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-8550193

RESUMEN

Isolates of Candida albicans from the oral cavities of subjects at different stages of human immunodeficiency virus (HIV) infection or uninfected controls were examined for (i) production of aspartic proteinase(s), a putative virulence-associated factor(s); (ii) the presence in the fungal genome of two major genes (SAP1 and SAP2) of the aspartic proteinase family; and (iii) experimental pathogenicity in a murine model of systemic infection. It was found that the fungal isolates from symptomatic patients secreted, on average, up to eightfold more proteinase than the isolates from uninfected or HIV-infected but asymptomatic subjects. This differential property was stably expressed by the strains even after years of maintenance in stock cultures. Moreover, representative high-proteinase isolates were significantly more pathogenic for mice than low-proteinase isolates of C. albicans. The characters high proteinase and increased virulence were not associated with a single molecular type or category identifiable through DNA fingerprinting or pulsed-field electrophoretic karyotype, and both SAP1 and SAP2 genes were present in both categories of isolates, on the same respective chromosomes. In conclusion, our data suggest that during HIV infection more-virulent strains or biotypes of C. albicans which are identifiable by direct analysis of virulence determinants are selected. It also appears that the biotype switch to increased aspartic proteinase and virulence properties occurs before the HIV-infected subject enters the symptomatic stage and overt AIDS.


Asunto(s)
Ácido Aspártico Endopeptidasas/metabolismo , Candida albicans/patogenicidad , Infecciones por VIH/microbiología , Boca/microbiología , Animales , Ácido Aspártico Endopeptidasas/genética , Candida albicans/enzimología , Genes Fúngicos , Humanos , Masculino , Ratones , Conejos , Virulencia
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