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1.
Retrovirus insertion into herpesvirus in vitro and in vivo.   总被引:12,自引:1,他引:12       下载免费PDF全文
Retroviruses and herpesviruses are naturally occurring pathogens of humans and animals. Coinfection of the same host with both these viruses is common. We report here that a retrovirus can integrate directly into a herpesvirus genome. Specifically, we demonstrate insertion of a nonacute retrovirus, reticuloendotheliosis virus (REV), into a herpesvirus, Marek disease virus (MDV). Both viruses are capable of inducing T lymphomas in chickens and often coexist in the same animal. REV DNA integration into MDV occurred in a recently attenuated strain of MDV and in a short-term coinfection experiment in vitro. We also provide suggestive evidence that REV has inserted into pathogenic strains of MDV in the past. Sequences homologous to the REV long terminal repeat are found in oncogenic MDV but not in nononcogenic strains. These results raise the possibility that retroviral information may be transmitted by herpesvirus and that herpesvirus expression can be modulated by retroviral elements. In addition, retrovirus may provide a useful tool to characterize herpesviral function by insertional mutagenesis.  相似文献   

2.
The DNA-containing Epstein-Barr herpesvirus has been implicated in the etiology of Burkitt's lymphoma, a malignant tumor of children in Africa. Recently, however, particles possessing four biochemical characteristics of RNA tumor viruses have also been identified in these tumors. The fact that both types of viruses are found suggests that an interaction between them may be playing a role in the etiology of Burkitt's lymphoma. To explore this possibility with a defined animal model, experiments were performed with the avian Marek's disease, a malignant lymphoproliferative disease associated with a herpesvirus. Controlled contact studies demonstrated that tumorigenesis in a line of isolator-derived, barrier-sustained, specific pathogen-free chickens requires exposure to both the Marek's disease herpesvirus and an avian leukosis virus, Rous-associated virus, type 2. Exposure to either agent alone did not result in tumors. Molecular hybridization experiments to cytoplasmic RNA from similarly contact-exposed conventional Cornell S-line chickens provided further evidence for the occurrence of an interaction between Marek's disease herpesvirus and the avian leukosis virus.  相似文献   

3.
Hepatitis B (HBV) and C (HCV) viruses are well-recognized causes for chronic hepatitis, cirrhosis, and even for hepatocellular carcinoma. Apart from liver disease, these viral infections are known to be associated with a spectrum of extrahepatic manifestations. The prevalence of clinically significant extrahepatic manifestations is relatively low, but it can be associated with significant morbidity and even mortality. An awareness and recognition of these manifestations is of paramount importance in facilitating early diagnosis and in offering treatment. However, treatments are not necessarily effective, and patients may continue with disabling extrahepatic manifestations. Hepatitis B virus has been well recognized as causing a variety of manifestations that include skin rash, arthritis, arthralgia, glomerulonephritis, polyarteritis nodosa, and papular acrodermatitis. More recently, infection with hepatitis C virus has elicited considerable interest for its role in a spectrum of extrahepatic manifestations. Among the best-reported are cryoglobulinemia, glomerulonephritis, high titer of autoantibodies, idiopathic thrombocytopenic purpura, lichen planus, Mooren’s corneal ulcer, Sjögren’s syndrome, porphyria cutanea tarda, and necrotizing cutaneous vasculitis. The precise pathogenesis of these extrahepatic complications has not been determined, although the majority represent the clinical expression of autoimmune phenomena.  相似文献   

4.
The DNAs of two herpesvirus, the oncogenic Marek disease virus and the serologically related herpesvirus of the turkey, were studied by electron microscopy. On the basis of fold-back molecules observed in single-stranded DNA from both viruses, structures have been derived from the overall nucleotide sequence arrangement in their genomes. Although differing in molecular weight, the genomes of Marek disease virus and turkey herpesvirus are both constructed according to the same plan--two regions of unique nucleotide sequence, each enclosed by inverted repeat sequence. The genome structure of these viruses therefore closely resembles that of herpes simplex virus rather than the biologically more similar herpesvirus Epstein--Barr virus, H. saimiri, and H. ateles.  相似文献   

5.
Marek disease is a lymphomatous disease of chickens caused by infection of a herpesvirus, Marek disease virus (MDV). Marek disease is the only neoplastic disease for which a successful vaccine has been developed. The vaccine virus, herpesvirus of turkeys (HVT), is non-oncogenic in chickens. Despite the strong antigenic relationship between these viruses, previous studies showed that the two viral DNAs share little or no homology. Using less stringent hybridization conditions and methods that greatly improve the reassociation kinetics, we have reexamined the sequence homology between MDV and HVT DNA. We report here that HVT and MDV are far more closely related than previously reported. The homology between these two viral DNAs ranges between 70% and 80% at the nucleotide level and appears to extend over 90-95% of the respective genomes. Under the low stringency conditions used, MDV DNA fails to cross-hybridize with DNA from feline rhinotracheitis virus, an antigenically unrelated herpesvirus with a G-C content identical to that of MDV and HVT.  相似文献   

6.
Fifth (erythema infectiosum) and sixth (roseola infantum) diseases are common rash illnesses of childhood that have long been recognized in clinical medicine. The discovery of the viruses that cause these illnesses has revealed relationships with other syndromes. Primary infection with the agent of erythema infectiosum, human parvovirus B19, is associated with transient aplastic crisis in hemolytic anemia, arthropathy in adults, chronic anemia in immunocompromised patients, and nonimmune fetal hydrops in pregnant women. The only documented illness associated with primary infection with human herpesvirus 6 is roseola or exanthema subitum in young children. However, reactivated infections in adults and immunocompromised patients may be associated with serious illness such as encephalitis/encephalopathy, and bone marrow suppression leading to transplant failure or graft-versus-host disease. Diagnostic studies for both viruses have been limited, although reliable serologic tests for human parvovirus B19 have recently become available. Diagnosis of human herpesvirus 6 remains problematic, because current tests cannot differentiate primary from reactivated disease. This is more of an issue for the putative relationship of these viruses to more chronic conditions, such as rheumatologic disease for human parvovirus B19 and multiple sclerosis for human herpesvirus 6. The relationship between the viruses and these conditions remains controversial, and better diagnostic tests and further information on viral pathogenesis for both viruses are required in order to make a reliable judgment in this regard.  相似文献   

7.
Cutaneous manifestations in HIV positive patients   总被引:1,自引:0,他引:1  
Cutaneous manifestations are common clinical findings among HIV positive patients. The causes may be bacteria, viruses, fungi and other non-infectious agents. This study was conducted at the Pramongkutklao Hospital skin clinic to determine the frequency distribution of cutaneous manifestations in HIV positive patients. A total of 147 patients with HIV seropositivity were recruited and divided into a retrospective group and a prospective study group. For the retrospective study, hospital records of 129 patients who attended from January 1995 to November 1998 were recruited. The prospective study was carried out from November 1998 to January 1999 and 18 patients were recruited. Cutaneous finding among patients in the two studies were evaluated. There were ten common cutaneous manifestations observed in the retrospective and prospective study including pruritic papular eruptions (PPE) (51.2%, 50%), oral candidiasis (16.7%, 21.7%), herpes zoster (10.9%, 5.6%), oral hairy leukoplakia (10%, 5.6%), unclassified eczema (9%, 11.1%), urticaria (5.6%, 3.1%), seborrheic dermatitis (4.7%, 16.7%), folliculitis (4.7%, 5.6%), prurigo simplex (4.7%, 5.6%), and Steven-Johnson syndrome (3.9%, 0%). However, the distribution of cutaneous manifestations in the two studies were not significantly different. These findings may be useful as baseline data for common cutaneous manifestations in HIV positive patients.  相似文献   

8.
A role for viruses in the development or course of the main idiopathic chronic infiltrative lung disease has been suggested for a long time. Viruses that have usually been incriminated in cryptogenic fibrosing alveolitis are hepatitis C virus, whose role has not been accurately proven, and latent viruses including Epstein-Barr virus and adenovirus. These latent viruses might be re-activated in the lung of patients immunocompromised by treatments and might be accountable for disease progression. However, published studies have been very conflicting and the only clinical trial testing ribavirin has failed to demonstrate a beneficial effect. In sarcoidosis, the responsibility of human herpesvirus 6 and 8 and retroviruses has not been proven. Finally, data in the literature do not support a link between Langerhans cell histiocytosis and human herpesvirus 6 and 8. These viruses may act by several mechanisms: viral proteins may be antigens driving an appropriate immune response; they may also behave as transactivating factors to control the expression of various genes involved in immune response, cell growth or synthesis of matrix proteins.  相似文献   

9.
African pygmy hedgehogs (Atelerix albiventris) are popular exotic pets in Japan, and their breeding numbers have recently increased. Although various diseases have been reported in hedgehogs, including skin, respiratory, neurological, and neoplastic diseases, most of the causes remain unidentified. In this study, we investigated herpesvirus, adenovirus, and coronavirus infections among 150 African pygmy hedgehogs in Japan and evaluated the correlations between virus infection and diseases. A novel herpesvirus named Atelerix albiventris herpesvirus 1 (AAHeV), and African pygmy hedgehog adenovirus 1 (AhAdV-1) were detected in 14 and 3 oral swab samples, respectively. AAHeV infection may be related to neurological clinical signs. Interestingly, no hedgehog with a neoplastic disorder tested positive for AAHeV. Further research is required to determine the pathogenicity and prevalence of the detected viruses.  相似文献   

10.
The oral cavity is often the first site where viruses interact with the human body. The oral epithelium is a major site of viral entry, replication and spread to other cell types, where chronic infection can be established. In addition, saliva has been shown as a primary route of person-to-person transmission for many viruses. From a clinical perspective, viral infection can lead to several oral manifestations, ranging from common intraoral lesions to tumors. Despite the clinical and biological relevance of initial oral infection, little is known about the mechanism of regulation of the viral life cycle in the oral cavity. Several viruses utilize host epigenetic machinery to promote their own life cycle. Importantly, viral hijacking of host chromatin-modifying enzymes can also lead to the dysregulation of host factors and in the case of oncogenic viruses may ultimately play a role in promoting tumorigenesis. Given the known roles of epigenetic regulation of viral infection, epigenetic-targeted antiviral therapy has been recently explored as a therapeutic option for chronic viral infection. In this review, we highlight three herpesviruses with known roles in oral infection, including herpes simplex virus type 1, Epstein–Barr virus and Kaposi’s sarcoma-associated herpesvirus. We focus on the respective oral clinical manifestations of these viruses and their epigenetic regulation, with a specific emphasis on the viral life cycle in the oral epithelium.  相似文献   

11.
Background: Histiocytic necrotizing lymphadenitis, also known as Kikuchi's disease (KD), is a rare disease. Fever and lymphadenopathies with characteristic pathologic features are present. The etiology of this disease remains undetermined. Since the disorder is self-limiting, different viruses have been implicated as the causative agent. Patients and Methods: Seven cases of KD were studied. Three patients acquired the disease nosocomially, three had community-acquired KD and one case was associated with systemic lupus erythematosus. PCR was performed on DNA extracted from lymph node tissues in order to detect herpesvirus-specific DNA sequences: herpes simplex virus type 1 and 2 (HSV 1–2), varicella zoster virus (VZV), human cytomegalovirus (HCM), human herpesvirus 6 (HHV6), Epstein-Barr virus (EBV) and human herpesvirus 8 (HHV8). Results: Viral DNA was not detected in any of the lymph node tissues from the seven cases of KD. Conclusion: We conclude that these herpesviruses were not involved in the etiology of the three cases of nosocomial KD nor in the other four cases of KD investigated in this study. Received: August 16, 2000 · Revision accepted: February 28, 2001  相似文献   

12.
The human Herpesviridae family consists of eight members: cytomegalovirus (CMV), Epstein-Barr virus (EBV), herpes simplex virus 1 and 2 (HSV-1, -2), varicella-zoster virus (VZV), and human herpesvirus 6, 7, and 8 (HHV-6, -7, -8). Lifelong latency may develop in the host with reactivation during periods of relative immunosuppression that occurs in transplant recipients. These are pleiotropic viruses: in addition to their direct effects of tissue injury and clinical illness, they exhibit several indirect effects, including immunomodulation and effects on angiogenesis and tumorigenesis, which may result in long-term adverse sequelae in the lung allograft. CMV and HHV-6 and -7 are increasingly recognized as major causes of morbidity and mortality in lung transplant recipients. EBV and HHV-8 have proven oncogenic potential. HSV-1 and -2 and VZV are neurotropic, causing perioral fever blisters, genital ulcerations, and, rarely, encephalitis. This article discusses the individual pathogens, preventive strategies in the era of potent treatment regimens for established viral infection or disease and their potential impact on the indirect effects of these viruses on long-term allograft function, and the incidence, risk factors for, and impact of antiviral resistance.  相似文献   

13.
Although well over 200 viral agents have been implicated in acute respiratory infections (ARIs) among children, no system able to detect such a wide range of viruses has been established. Between January 2004 and December 2005, a modified microplate method, including HEF, HEp-2, Vero E6, MDCK, RD-18S, and GMK cell lines (HHVe6MRG plate), was adopted to isolate viruses. A total of 1,551 viruses were isolated, representing both outbreaks and sporadic cases, from 4,107 nasopharyngeal specimens, at monthly isolation rates of 22.3 to 52.6%. Influenza, parainfluenza, respiratory syncytial (RS), and mumps viruses, and human metapneumovirus, enterovirus, parechovirus, rhinovirus, adenovirus, herpesvirus, and cytomegalovirus were all isolated. The use of multiple cell lines increased the isolation rates of most of these viruses. The findings showed that ARIs due to a number of respiratory viruses occurred across all seasons in succession and/or concurrently in children in the community. These data will help clinicians determine in which seasons and for which age groups they should use the rapid diagnostic test kits available for influenza virus, RS virus, and adenovirus. In conclusion, we verified that the modified microplate method was able to clarify the etiology and epidemiology of numerous viruses isolated from children with ARI.  相似文献   

14.
In March 2020, the World Health Organization declared coronavirus disease (COVID-19) a pandemic. As of February 2021, there were 107 million COVID-19 cases worldwide. As a comparison, there are approximately 38 million people living with human immunodeficiency virus (PLHIV) worldwide. The coexistence of both epidemics, and the syndemic effect of both viruses could lead to a delirious impact both at individual and community levels. Many intersecting points were found between severe acute respiratory syndrome coronavirus-2 (SARS-CoV-2), the causative agent of COVID-19, and HIV; among which, gastrointestinal (GI) manifestations are the most notable.GI manifestations represent a common clinical presentation in both HIV and SARS-CoV-2. The emergence of GI symptoms as a result of SARS-CoV-2 infection provides a new dynamic to COVID-19 diagnosis, management, and infection control measures, and adds an additional diagnostic challenge in case of coinfection with HIV. The presence of GI manifestations in PLHIV during the COVID-19 pandemic could be referred to HIV enteropathy, presence of opportunistic infection, adverse effect of antiretrovirals, or coinfection with COVID-19. Thus, it is important to exclude SARS-CoV-2 in patients who present with new-onset GI manifestations, especially in PLHIV, to avoid the risk of disease transmission during endoscopic interventions.Structural similarities between both viruses adds a valuable intersecting point, which has mutual benefits in the management of both viruses. These similarities led to the hypothesis that antiretrovirals such as lopinavir/Rironavir have a role in the management of COVID-19, which was the target of our search strategy using the available evidence. These similarities may also facilitate the development of an efficient HIV vaccine in the future using the advances in COVID-19 vaccine development.  相似文献   

15.
Leukemia is characterized by the production of an excessive number of abnormal white blood cells. Over time, this expanding population of poorly/non- functional white blood cells overwhelms the normal function of the body's blood and immune systems. DNA translocations have been found common to leukemia, including Raf mutations. While the cause of leukemia is not known, several risk factors have been identified. In this review, we present an update on the role of AIDS related viruses as an etiology for leukemia. Human immunodeficiency virus-1 and -2 (HIV-1; -2) are the cause for the development of acquired immune deficiency syndrome (AIDS). Epstein-Barr virus (EBV), human cytomegalovirus (HCMV), Human papillomavirus (HPV), and Kaposi's sarcoma-associated herpesvirus (KSHV) are specifically implicated in AIDS associated malignancies. However, there are other viruses that are associated to a lesser extent with the AIDS condition and they are Human T-cell leukemia virus-1 (HTLV-1), hepatitis B virus (HBV), hepatitis C virus (HCV), and human herpesvirus-6 (HHV-6). Of these viruses, HTLV-1 has been etiologically associated with leukemia. Recent evidence suggests that EBV, HBV, HCV, and KSHV may also play a role in the development of some types of leukemia. Raf signaling has been shown to aid in the infection and pathogenesis of many of these viruses, making Raf pathway components good potential targets for the treatment of leukemia induced by AIDS related viruses.  相似文献   

16.
Herpesviruses that infect fish   总被引:7,自引:0,他引:7  
Hanson L  Dishon A  Kotler M 《Viruses》2011,3(11):2160-2191
Herpesviruses are host specific pathogens that are widespread among vertebrates. Genome sequence data demonstrate that most herpesviruses of fish and amphibians are grouped together (family Alloherpesviridae) and are distantly related to herpesviruses of reptiles, birds and mammals (family Herpesviridae). Yet, many of the biological processes of members of the order Herpesvirales are similar. Among the conserved characteristics are the virion structure, replication process, the ability to establish long term latency and the manipulation of the host immune response. Many of the similar processes may be due to convergent evolution. This overview of identified herpesviruses of fish discusses the diseases that alloherpesviruses cause, the biology of these viruses and the host-pathogen interactions. Much of our knowledge on the biology of Alloherpesvirdae is derived from research with two species: Ictalurid herpesvirus 1 (channel catfish virus) and Cyprinid herpesvirus 3 (koi herpesvirus).  相似文献   

17.
PURPOSE OF REVIEW: Kaposi's sarcoma-associated herpesvirus or human herpesvirus 8, common in sub-Saharan Africa and around the Mediterranean Sea but rare in most other countries, is known to be transmitted in childhood within families in endemic regions, and through sexual contacts among high-risk groups in Western countries. Nevertheless recent developments on other modes of transmission of the virus have been made during the last years and are summarized in this review. Furthermore, recent published disease associations are discussed. RECENT FINDINGS: The last year has seen research addressing the question of parenteral transmission, sexual transmission through heterosexual contact, transmission of Kaposi's sarcoma-associated herpesvirus-infected cells from organ donors to recipient, as well as the first suggestion that host genetic factors may facilitate infection in childhood. Additional clinical manifestations of infection with the virus such as primary pulmonary hypertension and germinotropic lymphoproliferative disorder have been identified. SUMMARY: Evidence of Kaposi's sarcoma-associated herpesvirus transmission other than between homosexual adults and during childhood - namely transmission through heterosexual contact or injection drug use - is growing although these issues are still incompletely analysed and far away from being fully understood. Despite our increasing knowledge on transmission and disease associations of the virus, implications on the clinical management of associated diseases and public health have to be further evaluated in the coming years.  相似文献   

18.
Acute herpetic gingivostomatitis and recurrent herpes labialis are the most common manifestations of infection with herpes simplex virus type 1 (HSV-1). In primary and recrudescent HSV-associated disease, the symptoms may range from subclinical to debilitating and life-threatening, depending on the host’s immune responses or competence level. In this paper, the typical and atypical manifestations, and the current diagnostic and treatment options for localized, non-complicated oro-labial HSV infection are reviewed, with attention to cumulative evidence for the ef.cacy and safety of systemic antiviral agents. Some recent data on HSV-1 seroprevalence, viremia, and viral shedding are discussed in relation to disease transmission and global importance of herpesvirus disease.  相似文献   

19.
Human herpesvirus 6 (HHV-6) and HHV-7 are two recently identified beta-herpesviruses, genetically related to human cytomegalovirus (CMV). Infection with both viruses is common worldwide with rates of seropositivity in adults over 90%. Infection with both viruses usually occurs in early childhood. In this age group HHV-6 is a cause of febrile illness including exanthem subitum, and likewise, primary HHV-7 infection has been associated with febrile illness. Similar to the other human herpesviruses, in particular CMV, the viruses have the potential for enhanced pathogenicity in the immunocompromised host. Active infection with both viruses is common following bone marrow or solid organ transplantation, most likely through reactivation of recipient's virus or re-infection considering their high prevalence in the population. Both viruses can be detected by PCR in the peripheral blood of healthy individuals and although the significance of blood-borne transmission is not clear, a preliminary study suggested that it was not significant for HHV-6. However, there is growing evidence that these viruses may be medically important in the post-transplant period. In bone marrow transplant patients HHV-6 has been associated with a range of clinical disease including encephalitis, interstitial pneumonitis, early and late graft failure and bone marrow suppression. There is also growing evidence for potential interactions among the beta-herpesviruses in liver and renal transplant patients. HHV-6 infection has been associated with an increased risk of developing CMV disease and opportunistic infections and HHV-7 infection has also been linked to an increased risk of CMV disease.  相似文献   

20.
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