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2.
Infect Genet Evol ; 54: 183-191, 2017 10.
Article in English | MEDLINE | ID: mdl-28688977

ABSTRACT

BACKGROUND: The prevalence of HIV-1 drug resistance among treatment-naïve patients ranges between 8.3% and 15% in Europe and North America. Previous studies showed that subtypes A and B were the most prevalent in the Greek HIV-1 epidemic. Our aim was to estimate the prevalence of resistance among drug naïve patients in Greece and to investigate the levels of transmission networking among those carrying resistant strains. METHODS: HIV-1 sequences were determined from 3428 drug naïve HIV-1 patients, in Greece sampled during 01/01/2003-30/6/2015. Transmission clusters were estimated by means of phylogenetic analysis including as references sequences from patients failing antiretroviral treatment in Greece and sequences sampled globally. RESULTS: The proportion of sequences with SDRMs was 5.98% (n=205). The most prevalent SDRMs were found for NNRTIs (3.76%), followed by N(t)RTIs (2.28%) and PIs (1.02%). The resistance prevalence was 22.2% based on all mutations associated with resistance estimated using the HIVdb resistance interpretation algorithm. Resistance to NNRTIs was the most common (16.9%) followed by PIs (4.9%) and N(t)RTIs (2.8%). The most frequently observed NNRTI resistant mutations were E138A (7.7%), E138Q (4.0%), K103N (2.3%) and V179D (1.3%). The majority of subtype A sequences (89.7%; 245 out of 273) with the dominant NNRTI resistance mutations (E138A, K103N, E138Q, V179D) were found to belong to monophyletic clusters suggesting regional dispersal. For subtype B, 68.1% (139 out of 204) of resistant strains (E138A, K103N, E138Q V179D) belonged to clusters. For N(t)RTI-resistance, evidence for regional dispersal was found for 27.3% and 21.6% of subtype A and B sequences, respectively. CONCLUSIONS: The TDR rate based on the prevalence of SDRM is lower than the average rate in Europe. However, the prevalence of NNRTI resistance estimated using the HIVdb approach, is high in Greece and it is mostly due to onward transmissions among drug-naïve patients.


Subject(s)
Drug Resistance, Viral , HIV Infections/epidemiology , HIV Infections/virology , HIV-1/drug effects , Anti-HIV Agents/pharmacology , Anti-HIV Agents/therapeutic use , Female , Genotype , Greece/epidemiology , HIV Infections/drug therapy , HIV Infections/transmission , HIV-1/classification , HIV-1/genetics , Humans , Male , Mutation , Phylogeny , Prevalence
3.
J R Army Med Corps ; 162(1): 78-80, 2016 Feb.
Article in English | MEDLINE | ID: mdl-26126611

ABSTRACT

INTRODUCTION: It is known that the first radiological units were widely used during war conflicts, whereas the first application of military radiology took place during the Greco-Turkish War in 1897. However, until recently automobile radiology units were assumed to be used for the first time during World War I. METHOD: Historical archives and reports were researched, and extensive research in available literature was also conducted. RESULTS: The automobile radiology units were purchased from France and were probably constructed under the guidance of Marie Curie (1867-1934). The figure of Dr. Dimitrios Vasilidis (?-1937), a pioneer in Radiology in Greece and the first president of the Hellenic Radiological Society, is highlighted. DISCUSSION: This short historical note describes the first use of a mobile radiology unit during the Balkan Wars (1912-1913), predating its previously presumed first use in World War I. It also briefly highlights the contributions of some notable figures in 20th Century Greek scientific development.


Subject(s)
Military Medicine/history , Mobile Health Units/history , Radiology/history , Warfare , Balkan Peninsula , History, 19th Century , History, 20th Century , Humans , Military Personnel
4.
Cytopathology ; 25(4): 215-24, 2014 Aug.
Article in English | MEDLINE | ID: mdl-23763547

ABSTRACT

The purpose of our study was to summarize the knowledge on exfoliative cytology during the 19th century and to track down Papanicolaou's predecessors. A thorough study of texts, medical books and reports, together with a review of the available literature in PubMed, was undertaken. The study of cytological preparations as a diagnostic procedure can be traced back to the work of the famous French microscopist Alfred François Donné. However, the systematic study and the criteria for the diagnosis of malignant cells should be attributed to Johannes Müller. The increasing interest in the cytological examination of various fluids of the human body can be confirmed by a plethora of studies published during this period. By the end of the 19th century, the invention of new techniques in pathology, such as the introduction of cell block techniques, tissue sections and new staining methods which provided the opportunity to study surgical specimens in three dimensions, led to a decrease in the interest in exfoliative cytology, which was re-discovered by George Papanicolaou almost three decades later.


Subject(s)
Cell Biology/history , Cytodiagnosis/history , History, 19th Century , Humans , PubMed
5.
Transpl Infect Dis ; 15(4): 393-9, 2013 Aug.
Article in English | MEDLINE | ID: mdl-23773581

ABSTRACT

PURPOSE: The purpose of this study was to present a fatal case of fulminant hepatitis B (FHB) that developed in a renal transplant recipient, immunized against hepatitis B, 1 year post transplantation. METHODS: Polymerase chain reaction amplification and full genome sequencing were performed to investigate whether specific mutations were associated with hepatitis B virus (HBV) transmission and FHB. RESULTS: Molecular analysis revealed multiple mutations in various open reading frames of HBV, the most important being the G145R escape mutation and a frameshift mutation-insertion (1838insA) within the pre-C/C reading frame. CONCLUSIONS: Our results highlight the possibility of developing FHB, despite previous immunization against HBV or administration of hyperimmune gammaglobulin, because of the selection of escape virus mutants. The current literature and guidelines regarding renal transplantation from hepatitis B surface antigen (HBsAg)-positive to HBsAg-negative patients were also reviewed.


Subject(s)
Hepatitis B Surface Antigens/blood , Hepatitis B/virology , Kidney Transplantation/adverse effects , Liver Failure, Acute/virology , Mutation , Tissue Donors , Fatal Outcome , Hepatitis B/diagnosis , Hepatitis B/immunology , Hepatitis B/transmission , Hepatitis B Surface Antigens/immunology , Hepatitis B virus/genetics , Humans , Liver Failure, Acute/diagnosis , Liver Failure, Acute/immunology , Male , Middle Aged , Sequence Analysis, DNA
6.
Epilepsy Behav ; 18(3): 151-61, 2010 Jul.
Article in English | MEDLINE | ID: mdl-20493781

ABSTRACT

The purpose of this study was to reveal the major views of the early scientific period (18th and 19th centuries) on epilepsy as both a disease and a symptom. The shaping of thought about illness and medicine as a science, which began in the Renaissance and progressed into the Enlightenment, intensified during the 18th and 19th centuries. During this period of increasingly methodical investigation, researchers undertook a thorough study of epilepsy. Renowned doctors of this period from the Dutch and German medical schools, the "golden era" of French medicine, and British medicine, including, of course, John Hughlings Jackson, all left their mark in this era of epilepsy research. Epidemiological studies using large patient data sets were conducted for the first time, as was systematic research on the pathophysiological, pathological, neurological, and psychiatric aspects of the disease.


Subject(s)
Biomedical Research/history , Epilepsy/history , Animals , Biomedical Research/methods , Books, Illustrated/history , Epilepsy/epidemiology , Europe , History, 17th Century , History, 18th Century , History, 19th Century , Humans
7.
Diagn Cytopathol ; 38(7): 473-6, 2010 Jul.
Article in English | MEDLINE | ID: mdl-19813255

ABSTRACT

The purpose of our study is to elaborate on the ongoing controversy regarding the origination of the Pap test between the supporters of George Papanicolaou and Aurel Babes. We studied the original articles published by Aurel Babes and George Papanicolaou and conducted a comparative evaluation of both methods. Babes' method is radically different from Papanicolaou's method. Differences included the sampling method, the fixation and staining technique, and the interpretation of the results regarding cases of cervical cancer. We conclude that the establishment of the technique in clinical practice and the idea of its application as preventive control of cervical cancer belong solely to George Papanicolaou.


Subject(s)
Papanicolaou Test , Vaginal Smears/history , Vaginal Smears/methods , Animals , Female , Guinea Pigs , History, 20th Century , Humans , Staining and Labeling , Tissue Fixation , Uterine Cervical Neoplasms/diagnosis , Uterine Cervical Neoplasms/prevention & control
8.
J Clin Microbiol ; 47(8): 2544-50, 2009 Aug.
Article in English | MEDLINE | ID: mdl-19553583

ABSTRACT

Mutations in the highly conserved tyrosine-methionine-aspartate-aspartate (YMDD) motif are frequently associated with resistance to antivirals and represent a major concern in the treatment of hepatitis B virus (HBV) infection. Conventional methods fail to detect minority populations of drug-resistant viral quasispecies if they represent less than 25% of the total sample virus population. The amplification refractory mutation system real-time PCR (ARMS RT-PCR) was combined with molecular beacon technology using the LightCycler system. The samples from HBV patients selected for assay evaluation included (i) 57 samples from treatment-naïve patients for biological discriminatory ability (cutoff) estimation, (ii) 12 samples from patients with treatment failure that were M204V positive by sequencing, and (iii) 13 samples from patients with treatment failure that were negative for mutation at codon 204 by sequencing. The discriminatory ability of the assay was 0.25% when tested with laboratory-synthesized DNA target sequences. The median mutant-to-wild-type ratio for samples from naive patients tested positive for the wild type and for mutant variants was 0.01% (5th and 95th percentiles = 0.0001 and 0.04%, respectively). A value of 0.04% was selected as the biological cutoff of the assay of clinical samples. In all samples M204V positive by sequencing (12/12), the mutant variant was detected as the predominant population (range, 82.76 to 99.43%). Interestingly, in 5 (38%) of 13 samples negative by sequencing, the M204V variant was detected at a ratio above the biological cutoff (0.05 to 28%). The assay represents an efficient technique for the early detection and quantification of M204V variants before mutant strains emerge to dominate the population.


Subject(s)
Drug Resistance, Viral , Hepatitis B virus/genetics , Hepatitis B virus/isolation & purification , Hepatitis B/virology , Microbial Sensitivity Tests/methods , Mutation, Missense , Polymerase Chain Reaction/methods , Genotype , Hepatitis B/drug therapy , Humans , Sensitivity and Specificity
10.
J Urol ; 180(6): 2330-2; discussion 2322, 2008 Dec.
Article in English | MEDLINE | ID: mdl-18930260

ABSTRACT

PURPOSE: We present the evolution of ideas on the concept of proteinuria from antiquity through the 19th century. MATERIALS AND METHODS: We conducted a thorough study of texts, medical books and reports along with a review of the available literature in PubMed. RESULTS: Observations on proteinuria date back nearly 2,500 years to the works of Hippocrates. In the 17th and 18th centuries physicians and clinical chemists, particularly Frederick Dekkers, Domenico Cotugno and Charles Wells, further increased the knowledge of proteinuria. Contrary to popular belief the first appearance of the term albuminuria in print should be attributed to Martin Solon in 1837. CONCLUSIONS: Observations on proteinuria span approximately 2,500 years. The work of physicians during the 17th and 18th centuries led to its establishment as a separate clinical entity associated with renal disease.


Subject(s)
Proteinuria/history , History, 15th Century , History, 16th Century , History, 17th Century , History, 18th Century , History, 19th Century , History, Ancient , History, Medieval
11.
Infect Genet Evol ; 7(3): 354-60, 2007 Jun.
Article in English | MEDLINE | ID: mdl-16720108

ABSTRACT

Though recombination is an important evolutionary strategy in RNA viruses, only two cases of HCV recombinant strains have been reported. Our objective was to analyze the evolutionary history of the HCV genotypes aiming to obtain evidence of significant phylogenetic discordance due to either recombination or selective forces leading to convergent/divergent evolution. The data support an evolutionary preservation of the interferon-resistance related genomic region (ISDR) for the genotypes 1 and 4. On the other hand, there was no evidence that recombination has occurred in the past with the possible exception of genotype 4. Moreover, it is evidenced that genotypes 3 and 10 split more recently than genotypes 6-9 and 11. This analysis reverberates a commonly found pattern in rapidly evolving viruses, that is the strongly disturbed evolutionary history which deforms the uniform distribution of the phylogenetic relationships across the genome, and introduces a conservative inference framework for approaching this kind of data.


Subject(s)
Evolution, Molecular , Genome, Viral/genetics , Genotype , Hepacivirus/classification , Hepacivirus/genetics , Phylogeny , Recombination, Genetic/genetics , Molecular Sequence Data
12.
Virus Res ; 112(1-2): 115-22, 2005 Sep.
Article in English | MEDLINE | ID: mdl-16022906

ABSTRACT

The prevalence of HIV-1 drug resistance mutations in naïve patients has been previously shown to differ greatly with the geographic origin. The purpose of this study was to prospectively estimate the prevalence of HIV-1 drug resistance in Greece by analyzing a representative sample of newly HIV-1 diagnosed patients, as part of the SPREAD collaborative study. Protease (PR) and partial reverse transcriptase (RT) sequences were determined from 101 newly diagnosed HIV-1 patients, in Greece, during the period September 2002--August 2003, representing one-third of the total newly diagnosed HIV-1 patients in the same time period. The prevalence of HIV-1 drug resistance was estimated according to the IAS-USA mutation table taking into account all mutations in RT and only major mutations in PR region. The overall prevalence of resistance was 9% [95% confidence interval (CI): 4.2--16.2%]. The prevalence of mutations associated with resistance to NRTIs was 5% (95% CI: 1.6--11.2%), for NNRTIs was 4% (95% CI: 1.1--9.8%), while no major resistance mutations were found in PR. No multi-class resistance was detected in the study population. The prevalence of resistant mutations in the recent seroconverters was 22%. For two individuals, there was clear evidence for transmitted resistance based on epidemiological information for a known source of HIV-1 transmission. The prevalence of the HIV-1 non-B subtypes and recombinants was 52%.


Subject(s)
Drug Resistance, Viral/genetics , HIV Infections/epidemiology , HIV Infections/virology , HIV-1/drug effects , Mutation , Adult , Anti-HIV Agents/pharmacology , Female , Greece/epidemiology , HIV Infections/diagnosis , HIV Protease/genetics , HIV Protease Inhibitors/pharmacology , HIV Reverse Transcriptase/genetics , HIV-1/classification , HIV-1/genetics , Humans , Male , Microbial Sensitivity Tests/methods , Middle Aged , Prevalence , Reverse Transcriptase Inhibitors/pharmacology , Sequence Analysis, DNA
13.
Infect Genet Evol ; 5(3): 225-9, 2005 Apr.
Article in English | MEDLINE | ID: mdl-15737913

ABSTRACT

One of the main characteristics of the HIV-1 is its extensive genetic heterogeneity. Intersubtype recombination was first described in 1995 and since then a significant proportion of the HIV-1 isolates was found to comprise mosaic sequences. Re-analysis of 34 full-length HIV-1 intersubtype recombinants, including all "pure" HIV-1 subtypes revealed that 19 of the 34 analyzed mosaics consist of a more complex mosaic pattern than initially described. These findings indicate that the complexity of the HIV-1 recombinants is much greater than previously estimated.


Subject(s)
HIV-1/genetics , Recombination, Genetic , Genetic Variation , Phylogeny , Sequence Alignment/methods , Sequence Analysis/methods , Software
14.
J Med Virol ; 74(3): 369-72, 2004 Nov.
Article in English | MEDLINE | ID: mdl-15368527

ABSTRACT

The origin of the severe acute respiratory syndrome-coronavirus (SARS-CoV) remains unclear. Evidence based on Bayesian scanning plots and phylogenetic analysis using maximum likelihood (ML) and Bayesian methods indicates that SARS-CoV, for the largest part of the genome ( approximately 80%), is more closely related to Group II coronaviruses sequences, whereas in three regions in the ORF1ab gene it shows no apparent similarity to any of the previously characterized groups of coronaviruses. There is discordant phylogenetic clustering of SARS-CoV and coronaviruses sequences, throughout the genome, compatible with either ancient recombination events or altered evolutionary rates in different lineages, or a combination of both.


Subject(s)
Severe acute respiratory syndrome-related coronavirus/classification , Severe acute respiratory syndrome-related coronavirus/genetics , Evolution, Molecular , Genome, Viral , Humans , Phylogeny , Recombination, Genetic , Sequence Alignment , Viral Proteins/genetics
15.
Virus Res ; 85(1): 109-15, 2002 Apr 23.
Article in English | MEDLINE | ID: mdl-11955643

ABSTRACT

The widespread use of antiviral drugs against HIV has increased the prevalence of HIV-1 resistant strains among naïve individuals due to transmission of resistant strains. The purpose of this study was to investigate the presence of HIV-1 strains harboring resistance mutations in naïve patients in Greece. Blood samples were collected from 25 individuals. The DNA sequence of protease and partial reverse transcriptase regions (codons 41-223) were obtained by direct sequencing. Our results showed the absence of any primary resistance mutations in the study population. However, we were able to identify high prevalence of sequence polymorphisms at positions in reverse transcriptase region associated mainly with resistance to NNRTIs. Moreover, in protease region several secondary mutations were detected, suggesting the higher genetic variability of this region. The clinical significance of the polymorphisms associated with reduced susceptibility to NNRTIs remains to be clarified.


Subject(s)
Anti-HIV Agents/therapeutic use , Drug Resistance, Viral/genetics , HIV Infections/virology , HIV-1/drug effects , HIV-1/genetics , Mutation , Amino Acid Sequence , Gene Frequency , Genotype , Greece , HIV Infections/drug therapy , HIV Protease/genetics , HIV Reverse Transcriptase/genetics , Humans , Molecular Sequence Data , Polymorphism, Genetic , Reverse Transcriptase Inhibitors/pharmacology
16.
J Gen Virol ; 82(Pt 10): 2509-2514, 2001 Oct.
Article in English | MEDLINE | ID: mdl-11562543

ABSTRACT

Recombination is one of several factors that contribute to the great genetic diversity of human immunodeficiency virus type 1 (HIV-1). In the current study, analysis of the full-length genome of a novel complex mosaic HIV-1 isolate (99GR303) from a Greek sailor who was possibly infected in Sierra Leone, Africa is presented. The 99GR303 isolate was found to comprise genomic regions belonging to subtypes A, G, J and K as well as of regions of a subtype that remains unclassified. For a partial region of env as well as vpr, no apparent similarity to the known HIV-1 subtypes or to any of the circulating recombinant forms was found. In fact, in the partial env gene, including the C2-V3 region, the 99GR303 isolate formed a new clade, suggesting the existence of an additional HIV-1 subtype. Thus, novel recombinants embody partial genomic regions which may have originated either from subtypes that existed in the past and became extinct or from contemporary subtypes that are extremely rare.


Subject(s)
HIV-1/classification , Recombination, Genetic , Acquired Immunodeficiency Syndrome/virology , Base Sequence , HIV-1/genetics , Humans , Molecular Sequence Data , Phylogeny
18.
AIDS Res Hum Retroviruses ; 15(8): 745-58, 1999 May 20.
Article in English | MEDLINE | ID: mdl-10357470

ABSTRACT

Phylogenetic analysis of partial env sequences of HIV-1 isolates from Cyprus and Greece suggested the existence of a distinct subtype of the virus, designated as I. We examined whether this subtype represents a distinct group, or a mosaic consisting of previously characterized subtypes. The full-length sequences under consideration were recovered from serum samples of "subtype I" obtained from two nonepidemiologically linked HIV-1-infected subjects in Greece. The first subject was an intravenous drug user (IDU), while the second was a vertically infected child born in 1984 whose parents were both IDUs. A variety of methods, such as diversity plots as well as phylogenetic and informative site analyses, were used to classify the DNA sequences. Subsequent detailed analysis revealed a unique genomic organization composed of alternating portions of subtypes A, G, and I. The two Greek isolates formed a distinct group in most of the pol, gp120, and gp41 regions, and in the vif/vpr, vpu, LTR, and 5' terminus of nef. In contrast, different parts of env and gag as well as the 3' pol region, and the first exons of tat and rev, appeared to have arisen from subtypes A and G. Our results indicate that subtype I, which was probably circulating in Greece in the early 1980s, is a triple mosaic consisting of A, G, and I sequences.


Subject(s)
Genome, Viral , HIV Infections/virology , HIV-1/classification , HIV-1/genetics , Recombination, Genetic , Adolescent , Cyprus , DNA, Viral/genetics , Genes, env , Genes, gag , Genes, nef , Genes, pol , Genes, vpr , Genes, vpu , Greece , HIV Infections/complications , HIV Infections/transmission , HIV Long Terminal Repeat/genetics , Humans , Infectious Disease Transmission, Vertical , Phylogeny , Polymerase Chain Reaction , Sequence Analysis, DNA , Substance Abuse, Intravenous/complications
19.
J Hum Virol ; 2(6): 339-43, 1999.
Article in English | MEDLINE | ID: mdl-10774550

ABSTRACT

OBJECTIVES: To investigate the subtype classification of the circulating virus strains among human immunodeficiency virus type 1 (HIV-1)-infected children in Greece. STUDY DESIGN/METHODS: Since the beginning of the acquired immunodeficiency syndrome (AIDS) epidemic in Greece in 1982, 23 children have been reported to be vertically infected with HIV-1. Blood samples were available for 19 of these children, and the C2-C4 env region was successfully amplified by nested polymerase chain reaction (PCR) for 16 subjects. HIV-1 subtype was established by the heteroduplex mobility assay (HMA) in 16 subjects and confirmed by DNA sequencing and phylogenetic analysis in 8 subjects. RESULTS: Most subjects (9; 56%) fell into subtype B. However, a substantial proportion (44%) were classified as subtypes A (3; 19%), C (1; 6%), D (1; 6%), and I (2; 12%). According to epidemiologic information, 5 of 7 children infected with non-B HIV-1 subtypes were born to Greek parents. CONCLUSION: These findings clearly suggest that non-B strains have been introduced into Greece, providing evidence that HIV epidemic in this country will probably change profile over time. In addition, subtype I was identified in 2 HIV-1-infected children, both of whom were born to Greek parents.


Subject(s)
HIV Infections/transmission , HIV-1/classification , Infectious Disease Transmission, Vertical , Molecular Epidemiology , Adolescent , Adult , Child , Child, Preschool , DNA, Viral/analysis , DNA, Viral/genetics , Female , Greece/epidemiology , HIV Infections/epidemiology , HIV Infections/virology , HIV-1/genetics , HIV-1/physiology , Heteroduplex Analysis , Humans , Male , Phylogeny , Polymerase Chain Reaction , Sequence Analysis, DNA
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