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PubMed2004

Influenza-associated hospitalizations in the United States.

CONTEXT: Respiratory viral infections are responsible for a large number of hospitalizations in the United States each year. OBJECTIVE: To estimate annual influenza-associated hospitalizations in the United States by hospital discharge category, discharge type, and age group. DESIGN, SETTING, AND PARTICIPANTS: National Hospital Discharge Survey (NHDS) data and World Health Organization Collaborating Laboratories influenza surveillance data were used to estimate annual average numbers of hospitalizations associated with the circulation of influenza viruses from the 1979-1980 through the 2000-2001 seasons in the United States using age-specific Poisson regression models. MAIN OUTCOME MEASURES: We estimated influenza-associated hospitalizations for primary and any listed pneumonia and influenza and respiratory and circulatory hospitalizations. RESULTS: Annual averages of 94,735 (range, 18,908-193,561) primary and 133,900 (range, 30,757-271,529) any listed pneumonia and influenza hospitalizations were associated with influenza virus infections. Annual averages of 226,54 (range, 54,523-430,960) primary and 294,128 (range, 86,494-544,909) any listed respiratory and circulatory hospitalizations were associated with influenza virus infections. Persons 85 years or older had the highest rates of influenza-associated primary respiratory and circulatory hospitalizations (1194.9 per 100,000 persons). Children younger than 5 years (107.9 primary respiratory and circulatory hospitalizations per 100,000 persons) had rates similar to persons aged 50 through 64 years. Estimated rates of influenza-associated hospitalizations were highest during seasons in which A(H3N2) viruses predominated, followed by B and A(H1N1) seasons. After adjusting for the length of each influenza season, influenza-associated primary pneumonia and influenza hospitalizations increased over time among the elderly. There were no significant increases in influenza-associated primary respiratory and circulatory hospitalizations after adjusting for the length of the influenza season. CONCLUSIONS: Significant numbers of influenza-associated hospitalizations in the United States occur among the elderly, and the numbers of these hospitalizations have increased substantially over the last 2 decades due in part to the aging of the population. Children younger than 5 years had rates of influenza-associated hospitalizations similar to those among individuals aged 50 through 64 years. These findings highlight the need for improved influenza prevention efforts for both young and older US residents.

Adolescent↗
PubMed1993

Risk factors for tumor recurrence and prognosis after curative resection of hepatocellular carcinoma.

METHODS: Eighty-three patients with hepatocellular carcinoma (HCC) were treated with curative surgical resection during the past 8 years. RESULTS: No operative deaths occurred. The cumulative recurrence rates after resection at the ends of years 1, 2, and 3 were 37.0%, 57.1%, and 71.6%, respectively. After adjusting the imbalance in clinical factors among patients by using a Cox proportional-hazards model, it was shown that multiplicity, histologic classification, and absence of antibody to hepatitis C virus were associated significantly with recurrence after resection. The size of the tumor did not affect the incidence of recurrence. Thirty-eight of 41 patients with intrahepatic tumor recurrence had undergone at least one of the following three therapies against HCC: surgical reresection, percutaneous ethanol injection (PEI), and transcatheter arterial embolization (TAE). The most significant factor affecting the survival time of patients with tumor recurrence was the total number of tumor nodules at the time of recurrence. Although surgery and PEI were thought to be more effective treatments than TAE in prolonging life, multivariate analysis showed that they were not significant factors of survival time because choices in the method of treatment were correlated closely with the number of cancer nodules. A 65.3% 5-year survival rate from the time of first surgery was accomplished through vigorous therapy when tumors recurred. CONCLUSION: In conclusion, despite the high recurrence rate after resection of HCC, the use of multiple therapies can achieve increased survival rates.

Adult↗
PubMed2002

Usefulness of tumor pressure as a prognostic factor in cases of hepatocellular carcinoma where the diameter of the tumor is 3 cm or less.

BACKGROUND: The current study was designed to determine the usefulness of pretreatment tumor pressure as a new prognostic factor in patients with small hepatocellular carcinoma (HCC; 3 cm or smaller in diameter). METHODS: The study included 39 patients with small HCC in whom tumor pressure was determined. They underwent percutaneous ethanol (with Lipiodol) injection therapy (Lp-PEI) or transcatheter arterial embolization (TAE) of the hepatic artery. Tumor pressure was determined percutaneously under ultrasonographic guidance. The factors analyzed were age, gender, mean blood pressure, the presence/absence of antibody to hepatitis C virus (anti-HCV), alcohol abuse, Child's classification, the presence/absence of esophagogastric varices, serum alpha-fetoprotein (AFP) level, tumor size, number of tumors, degree of tumor differentiation, the presence/absence of tumor capsule, tumor pressure, and the method of treatment. Multivariate analysis using Cox proportional hazards model was conducted on the factors that may have affected prognosis (P < 0.25) according to the univariate analysis using a proportional hazards model. RESULTS: The rates of local and distant recurrence were higher (P < 0.01, P < 0.01, respectively) and the survival rate was lower (P = 0.03) in patients with high tumor pressure than in those with low tumor pressure. Multivariate analysis revealed that tumor pressure (P < 0.01), AFP level (P = 0.01), and age (P = 0.01) were significant predictive factors associated with local recurrence. Tumor pressure (P < 0.01) and AFP level (P < 0.01) were both significantly associated with distant recurrence. The only significant predictive factor associated with survival rate was tumor pressure (P < 0.04). CONCLUSIONS: The current study revealed that tumor pressure was associated significantly with survival rates after Lp-PEI or TAE in patients with small HCC. There were also significant predictive factors associated with local recurrence, these being tumor pressure, AFP level, and age, and with distant recurrence, namely, tumor pressure and AFP level. Tumor pressure measured before the initial treatment of patients with small HCC may be a useful new prognostic factor.

Adult↗
PubMed2001

Complete coding sequence of the Alkhurma virus, a tick-borne flavivirus causing severe hemorrhagic fever in humans in Saudi Arabia.

To date, tick-borne flaviviruses responsible for hemorrhagic fever in humans have been isolated in Siberia (Omsk hemorrhagic fever virus), India (Kyasanur Forest disease virus, KFDV), and in Saudi Arabia (Alkhurma virus, ALKV). Prior to this study, only partial coding sequences of these severe pathogens had been determined. We report here the complete coding sequence of ALK virus, which was determined to be 10,248 nucleotides (nt) long, and to encode a single 3,416 amino acid polyprotein. Independent analyses of the complete polyprotein and the envelope protein provided genetic and phylogenetic evidence that ALKV belongs to the tick-borne flavivirus group, within which it is most closely related to KFDV. Analysis of structural genes, genetic distances, and evolutionary relationship indicate that ALKV and KFDV derived from a common phylogenetic ancestor and constitute two genetic subtypes of the same virus species according to current genetic criteria of classification.

Flavivirus↗
PubMed2006

Follicular localization of dendritic cells in a xanthomatous inflammatory tumor of lung associated with human herpes virus-8 infection.

A 17-year-old man was treated with chemotherapy and radiation for nodular sclerosing Hodgkin lymphoma that presented as a left chest wall mass. Ten years later, a left upper lobe lung tumor was identified. The tumor resection demonstrated a 1.3-cm yellow lung nodule composed of epithelioid and spindled lipid-laden CD68+ and Factor XIIIa+ macrophages. Distinct follicular structures with dendritic cells positive for CD1a, fascin, and ALK-1 and largely devoid of intracytoplasmic lipid were a distinguishing feature of the lesion. Most of the xanthomatous macrophages expressed human herpes virus-8 antigen. The current World Health Organization classification of "inflammatory myofibroblastic tumors" is examined, and the association of a subset of "inflammatory pseudotumors" with immunodeficiency states and opportunistic infection is discussed.

Activin Receptors, Type II↗
PubMed2006

Relationship between LAPTM4B gene polymorphism and susceptibility of gastric cancer.

BACKGROUND: A novel gene called LAPTM4B (lysosome-associated protein transmembrane 4beta) was mapped to 8q22, and contains seven exons. The 2.25-kb messenger RNA of the gene encodes a putative lysosome-associated protein with four transmembrane regions. There are two alleles of the gene, named as LAPTM4B*1 and LAPTM4B*2. Allele *1 differs from allele *2 in that it contains only one copy of a 19-bp sequence in the 5' untranslated region (UTR), whereas this sequence is duplicated and tandemly arranged in allele *2. Studies showed that the allelic variation of LAPTM4B was associated with the genetic susceptibility of hepatocellular carcinoma but not with that of esophageal squamous cell carcinoma. This study was designed to investigate the possible association between the allelic variation of LAPTM4B and the genetic susceptibility of gastric cancer. MATERIALS AND METHODS: The genotype of LAPTM4B was analyzed in 350 unrelated healthy adult individuals and 214 patients with gastric cancer by utilizing polymerase chain reaction based on specific primers. The genotypic distribution of LAPTM4B was analyzed by chi(2) test. RESULTS: The allelic frequencies of the *2 were 33.88% and 24.14% in the gastric cancer group and the healthy control group, respectively, which was significantly different between the two groups (P < 0.001). There was a significant difference in the overall genotypic distribution between the patients and the controls (P = 0.023). The risk of suffering from gastric cancer was increased 1.819 times in the individuals of the *1/2 genotype [95% confidence interval (CI) 1.273-2.601] and 2.387 times in the individuals of the *2/2 genotype of LAPTM4B (95% CI 1.195-4.767) compared with the *1/1 genotype. No association between the genotypic distribution of LAPTM4B and the clinical information on patients of gastric cancer such as age, pathological type, differentiation classification of TNM, and infection of hepatitis B virus was shown. CONCLUSION: This study indicated that allele *2 of LAPTM4B might be the risk factor of gastric cancer, which could be associated with genetic susceptibility of gastric cancer.

Adenocarcinoma↗
PubMed1987

Isolation of group A swine rotaviruses displaying atypical electropherotypes.

Swine rotaviruses displaying distinctive electropherotypes were isolated from the feces of diarrheic piglets in two swine herds in the province of Buenos Aires, Argentina. In one case all samples isolated showed abnormal electropherotypes. All samples were classified as group A reactive when assayed by an enzyme-linked immunosorbent assay. Three samples from this herd were adapted to grow in tissue culture. The electrophoretic pattern of the genomic RNA as well as the group A reactivity of one of these viruses was retained after cloning in MA-104 cells. In the other pig unit were found samples displaying both classical and abnormal electropherotypes. These viruses were also positive in the enzyme-linked immunosorbent assay; however, since they could not be adapted to grow in tissue culture, this classification must be considered tentative. The abnormal electropherotype exhibited by these pig viruses strongly resembles those of human origin called super short.

Animals↗
PubMed2002

The upstream regulatory region of human papillomavirus type 31 is insensitive to glucocorticoid induction.

The upstream regulatory region (URR) of various types of human papillomaviruses (HPVs) has been shown to contain functional glucocorticoid response elements (GREs), including HPV type 11 (HPV11), HPV16, and HPV18. Glucocorticoids have been demonstrated to induce the transcriptional activity of the early promoters of these HPV types. Although it has been assumed that the URR of HPV31 contains at least one GRE, no functionality has been demonstrated. We attempt to show here inducibility of the URR of HPV31 by the synthetic glucocorticoid dexamethasone (dex). By sequence analysis we identified three potential GREs in the URR of HPV31. Gel shift analysis indicated that each of these three sites has the potential to be a functional GRE. However, constructs containing the full-length URR, 5' deletions of the URR, and an internal fragment of the URR containing all three putative GREs were only weakly inducible by dex. Linker scanning mutants, whereby each potential GRE was replaced individually, in double combination, or in triple combination by a unique polylinker, had no effect on dex inducibility. Replacement of each of the three HPV31 GREs with the GRE of HPV18 failed to induce a response to dex. Placement of the HPV18 GRE into the URR of HPV31 in a region similar to its location in the HPV18 URR was also unable to result in a strong dex induction of the HPV31 URR. These data suggest that the lack of dex inducibility is due to the overall context of the HPV31 URR and may be dependent on the requirements of the major early promoter for transcriptional activation. Finally, replacement of the HPV18 GRE with each of the HPV31 GREs in HPV18 only showed weak inducibility, indicating that the three GREs of HPV31 are in fact only weak inducers of dex. Overall, these data suggest that dex responsiveness, along with oncogenic potential, may provide a possible explanation for the classification of HPV31 as an intermediate-risk virus and demonstrate the complexity of transcriptional regulation of the URR of HPV.

Dexamethasone↗
PubMed1992

[Anal and perianal lesions in symptomatic HIV infections. Prospective study of a series of 190 patients].

The aim of this study was to determine the prevalence and type of symptomatic anal and perianal diseases in patients belonging to group IV of the Centers for Disease Control classification of infections with human immuno-deficiency virus. Among the 190 prospectively included patients, 31 (16.3 percent) (30 men, 29 homosexuals or bisexuals; 1 woman) had anal symptoms and were referred for proctological examination. Thirty-five "specific" diagnoses were reached in 25 (13.2 percent) patients: 21 ulcerations, 7 condyloma acuminata, 6 perianal sepsis and 1 non-Hodgkin malignant lymphoma. The causes of ulcerations were 16 herpes, one syphilitic chancre and one fissure-in-ano. Three ulcerations remained unexplained despite bacteriological, viral, and histological investigations. Eight patients underwent 10 surgical procedures without significantly delayed wound healing.

Acquired Immunodeficiency Syndrome↗
PubMed1993

Classification of a new member of the TBE flavivirus subgroup by its immunological, pathogenetic and molecular characteristics: identification of subgroup-specific pentapeptides.

The antigenic, pathogenic and molecular characteristics of Turkish sheep encephalitis (TSE) virus, strain TTE80, were compared with other members of the tick-borne encephalitis (TBE) virus complex. Monoclonal antibodies with defined specificity for the flavivirus envelope glycoprotein distinguished TSE virus from louping ill (LI), western or far eastern TBE, Langat and Powassan virus in indirect immunofluorescence, haemagglutination-inhibition and neutralization tests. On the other hand, TSE virus, which produces an LI-like disease in sheep, resembled LI virus in mouse neurovirulence tests. Molecular homology data of all the structural genes of TSE virus compared with other tick-borne flaviviruses demonstrated that TSE virus is a distinct member in the TBE virus subgroup. The data are consistent with the conclusion that TSE virus has evolved by a separate evolutionary pathway as compared with the close antigenic relatives, western European, far eastern TBE viruses and LI virus. By aligning the encoded amino acids in the viral envelope glycoprotein of mosquito- and tick-borne flaviviruses, we have also identified subgroup-specific pentapeptide motifs for the tick-borne encephalitis, Japanese encephalitis and dengue subgroup viruses of the genus Flavivirus. These pentapeptides have important implications for the evolution, classification and diagnosis of flaviviruses.

Amino Acid Sequence↗
PubMed1994

Complementation of human immunodeficiency virus type 1 vif mutants in some CD4+ T-cell lines.

The viral infectivity factor gene, vif of human immunodeficiency virus type 1 (HIV-1), is required for full infectivity in most T-cell lines. The replication kinetics exhibited by these mutants has been shown to be cell type-dependent. In H9 cells as well as primary lymphocytes, vif mutants are incapable of establishing infection. This has led to classification of these cell types as non-permissive for vif mutant replication. The T-cell lines Sup T1 and C8166 are able to replicate the vif mutant virus, leading to their classification as permissive for vif mutant replication. In this study, four cell lines (Sup T1, C8166, Molt 4 Clone 8, and A3.01) were tested for their ability to replicate vif mutant virus derived from two different strains of HIV-1 (HXB2 and NL4-3) that had been passaged on various cell lines. Although the kinetics of initial infection was delayed in all cells, by the second passage of vif mutant virus on Sup T1 or Molt 4 cells the kinetics of replication were identical to wild type virus. In contrast, mutant virus displayed delayed replication kinetics in C8166 and A3.01 cells in both initial and subsequent passages. In addition, the levels of viral DNA in infected Sup T1 cells were similar for delta vif and wild type virus, but in C8166 cells delta vif virus DNA levels were reduced compared to wild type virus. These results argue that in Sup T1 and Molt 4 cells there is a factor present that is able to complement the defect in vif mutant viruses which is absent or inefficient in its activity in C8166 and A3.01 cells.

CD4-Positive T-Lymphocytes↗
PubMed1993

Morphological and genomic characterization of two reoviruses (P and W2) pathogenic for marine crustaceans; do they constitute a novel genus of the Reoviridae family?

P and W2 viruses are pathogenic in two crustaceans of the Mediterranean Sea, Macropipus depurator and Carcinus mediterraneus, respectively. Investigation of virus, virus density and genome structure leads us to propose their classification in a genus similar to aquareovirus of the Reoviridae family. They differ from aquareoviruses by the number of dsRNA segments forming the genome (12 instead of 11), their electrophoretic pattern in PAGE (1/5/6 instead of 3/3/5), and the absence of virus replication in fish cell lines.

Animals↗
PubMed2000

[Anti LKM-1 antibodies and cryoglobulinemia in autoimmune chronic hepatitis and virus C hepatitis].

BACKGROUND: Anti liver kidney microsome antibodies (LKM-1) have been recently incorporated to the study and classification of chronic autoimmune hepatitis (HC-A1). The presence of anti LKM-1 antibodies and essential cryoglobulinemia is frequent in virus C associated chronic hepatitis (HC-VC). AIM: To study the frequency of anti LKM-1 antibodies and cryoglobulin levels in patients with HC-AI, HC-VC and cryptogenic cirrhosis. PATIENTS AND METHODS: Forty-two patients were studied. Nineteen adult women with classic HC-AI with positive antinuclear or anti smooth muscle antibodies. Five patients of less than 20 years old with HC-AI and negative antinuclear and anti smooth muscle antibodies. Ten adult women with cryptogenic cirrhosis, 4 women and 4 men with HC-VC. Serum samples were obtained at 37 degrees C. Antinuclear, anti smooth muscle and anti LKM-1 antibodies were measured by indirect immunofluorescence using Hep-2 cells and rat tissue slices as substrates. Cryoglobulins were determined by the traditional method and cryocrit. RESULTS: All studied patients were anti LKM-1 negative. All had significant circulating cryoglobulin levels. CONCLUSIONS: In this sample of patients with HC-AI or HC-VC, anti LKM-1 antibodies were not detected but all had cryoglobulinemia.

Adolescent↗
PubMed1986

Classification of the papillomaviruses--mapping the genome.

Papillomaviruses form one genus of the Papovaviridae family. They share common antigenic determinants and their DNAs cross-hybridize under conditions of low stringency. The classification of papillomaviruses is at present based on the host range and the relatedness of the nucleic acids. Isolates are considered independent types if there is less than 50% cross-hybridization in the liquid phase according to a standard protocol. At least 31 human and six bovine papillomavirus types can be differentiated on this basis. The host range does not reflect the natural relationship between the viruses. Subgenera, which differ in biological properties, can be distinguished in outline. Data on overall sequence homology are insufficient for a meaningful classification because two types of virus may be closely related within one genome region and rather heterogeneous in other areas. Some new isolates appear as intermediates between previously well-separated types and complicate the system. A reasonable classification of such types of papillomavirus should be based on homologies between genes that are relevant for differences in the biology of the viruses. A functional mapping of the rather uniformly organized, colinear genomes of papillomaviruses has been started. Genetic studies with bovine papillomavirus type 1 have assigned functions in replication, transformation, gene expression and capsid synthesis to individual open reading frames.

Amino Acid Sequence↗
PubMed1987

Demonstration of bovine viral diarrhoea virus in peripheral blood mononuclear cells of persistently infected, clinically normal cattle.

Peripheral blood mononuclear cells (PBL) from cattle known to be persistently viraemic with bovine viral diarrhoea virus (BVDV) following a foetal infection, were examined for the presence of viral antigens and cell-associated infectious virus. Using immunocytochemical techniques, physical separations of PBL subsets and virus isolation techniques (directly and by cocultivation) it was found that infection occurred in B and T lymphocytes, monocytes, and a group of cells designated null cells for lack of more specific classification. The latter three groups also supported viral replication, as infectious virus could be isolated from enriched cell populations. BVDV-like particles in cytoplasmic vesicles of PBL subsets were detected by electron microscopy.

Animals↗
PubMed1987

[The 1985 influenza epidemic in a pediatric practice].

Because it is not possible to distinguish clinically influenza from other respiratory infections, virological methods have to be used to establish the influenza etiology. Nasopharyngeal swabs from 202 children with respiratory symptoms were taken. Influenza A virus (H3N2) was isolated from 44 children, influenza A virus (H1N1) from 61 children and influenza B virus from 13 children. The maximal activity of the two influenza A virus subtypes was different. The following features permitted the classification of 3 groups; monophasic fever greater than or equal to 38.5 degrees C (81.35%), biphasic fever (14.41%), and pseudocroup (4.24%). 16.1% of the children with fever also had gastrointestinal symptoms. No relation between influenza type/subtype and type of manifestation could be established.

Child↗