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In Mexico, the presence of highly pathogenic avian influenza AH7N3 affects the poultry industry since 2012, causing economic losses and being a subtype of concern due to its pandemic potential. Influenza viruses can block the immune response of the host by inhibiting interferons /β by effects of NS1 protein. Many studies show that truncations in NS1 protein can be the key to obtaining live attenuated vaccine candidates. Using reverse genetics and based on the H7N3 influenza full genome of a Mexican strain, recombinant viruses possessing a full-length NS1 or a truncated NS1 protein at the carboxyl-terminal at 99 or 126 amino acids were generated. All rescued viruses replicated to HA titers of 1:160 in MDCK cells. In growth kinetics assays, truncated viruses showed attenuation compared with full-length NS1 viruses in MDCK cells. The measurement of interferon mRNA production by infection assay in chicken embryo primary cell cultures, showed that truncated viruses were able to reduce IFN inhibition up to 5-fold compared to wild-type viruses. This is the first report of the rescue of recombinant viruses from full genome H7N3 subtype and the generation of two H7N3 viruses with truncated NS1 protein as potential candidates of live attenuated vaccines. [ABSTRACT FROM AUTHOR]

G-quadruplexes (G4s) play a crucial role in viral life cycles, regulating essential processes such as replication, transcription, and translation. Recently, G4 structures have garnered attention from the scientific community due to their potential applications as aptamers, cancer treatments, or antiviral targets. In our laboratory, we have identified putative G-quadruplex sequences in regions of the Human Papillomavirus 16 (HPV16) genome that require experimental confirmation. In this study, we standardized a real-time quantitative PCR stop assay (qPCR stop) to determine the degree of amplification inhibition caused by G4s in the HPV16 genome. Specific primers were designed to detect G4s in E1, E2, E6, L1, L2 genes, and the promoter region. To validate the technique, we used plasmid DNA, containing a DNA-G4 region reported for HPV52 (5O4D) as a reference. Additionally, we determined optimal KCl concentrations for G4 formation, as well as for the ligands PhenDC3 and Pyridostatin. Our results demonstrated that qPCR stop has the capability to distinguish between regions with and without G4s, validating its utility as a reliable tool for detecting and investigating these structures, which may have potential clinical applications in other HPV genotypes. Also, a list of potential G4s is provided for future biophysical and functional studies. [ABSTRACT FROM AUTHOR]

The article determines the electrophoretic karyotype of Mycosphaerella fijiensis using contour-clamped homogenous electric field gel electrophoresis. The highest variation in banding profiles was found in the chromosomes with sizes below 1.5 megabases pairs. The physical and genetic mapping of the fungus could lead to the development of new strategies for the control of black Sigatoka.

Focal Epithelial Hyperplasia or Multifocal Epithelial Hyperplasia (MEH), also known as Heck's disease, is considered a rare pathology of the oral mucosa associated with human papillomavirus types 13 and 32. For reasons not fully understood, MEH disproportionally affects specific populations of indigenous groups around the world. After the first reports in Native Americans, the epidemiology of the disease has been described in different geographical regions mainly related to particular indigenous populations, the majority of the studies are clinical case reports, but the biological determinants are still unknown. Some suggested risk factors include chronic irritation caused by smoking, a galvanic current, vitamin A deficiency, and/or a familial-genetic predisposition; however, the scientific evidence is not solid due the scarcity of case-control studies or longitudinal cohorts. In light of the evidence, further study of the pathology of MEH should be considered and proper clinical trials for effective treatments should be designed. The disease warrants further study as it is considered as neglected by research and it affects rural/remote population groups usually living in adverse socioeconomic conditions., Competing Interests: The authors declare that this work was conducted in the absence of any commercial or financial relationships that could be construed as a potential conflict of interest., (Copyright © 2024 Conde-Ferráez and González-Losa.)

High-Risk Human Papillomavirus (HR-HPV) types 16 and 18 are estimated to be responsible for 72.4% of all HPV-related cancers worldwide in both men and women, including cervical, anal, penile, vulval, vaginal and head and neck cancers [1]. Important efforts worldwide have devoted to the study of these genotypes, throughout epidemiology and basic science approaches. Of particular interest are the genes from the early region (E), coding non-structural proteins. Early genes E1 and E2 products are involved in replication and transcription regulation, while E6 and E7 proteins are recognised for their oncogenic potential. In this data report, we described a set of primers based on reference sequences from HPV16 and HPV18 designed to cover the early region of these oncogenic genotypes. The design was based on multiple sequences alignment to identify the less conserved regions along the open reading frames (ORFs) E6, E7, E1 and E2. The design allows a highly stringent real time PCR essay ranged from 123 to 598 bp overlapping products for HPV16 (12 products in total) and from 183 to 526 bp for HPV18 (11 products in total), both spanning the early genomic region. The high annealing temperatures (Ta) and regions selected for primer bind were intended for genotypic specificity, without compromising the qPCR amplification efficiency (≥ 90%). Evaluation of qPCR conditions for primer set was performed using DNA standards as controls, generated from the HPV16 and 18 genomes clones. This provides relevant information for further multiple quantitative real-time PCR analysis (qPCR), using the SYBR green chemistry, which is is more affordable than generating multiple fluorescently labeled probes., Competing Interests: The authors declare that they have no known competing financial interests or personal relationships which have, or could be perceived to have, influenced the work reported in this article., (© 2023 The Authors.)

The incidence of anal intraepithelial neoplasias associated with HPV is rising worldwide. In the general population, this pathology is rare, but individuals living with HIV/AIDS are at a significantly higher risk. We aimed to study HPV infection and performed cytological screening to study the epidemiological and behavioral determinants in a group of men and women living with HIV from a region in Mexico with high HIV incidence. This was a cross-sectional study including adults living with HIV/AIDS performed in Merida (Mexico). We invited patients of public HIV/STD clinics and those affiliated with social organizations of people living with HIV to participate in the study. Participants responded to an instrument to assess their risky behaviors and clinical history. Swabs from the anal canal and cervix and anal cytology specimens were obtained by medical staff from women and by self-sampling from men. For the 200 participants, 169 men and 31 women, anal HPV PCR tests resulted in 59.8% positivity (62.6% of men and 45.2% of women), and 17 genotypes were identified. The most frequent high-risk (HR) types for the anal canal were: HPV33 (35.3%), HPV58 (20.6%), HPV66 (18.6%), HPV45 (17.6%), and HPV16 (14.7%). Multiple genotypes were found in over 80% of the participants. Receptive anal intercourse in the previous 12 months, inconsistent condom use, and detectable HIV titers (≥50 cc/mL) were associated with HPV infection ( p < 0.05). Cytology (smears and liquid-based) identified that 34.6% of the participants had low-grade squamous intraepithelial lesions (LSILs), and 3.5% had high-grade squamous intraepithelial lesions (HSILs). Neither HPV nor lesions were associated with low CD4+ counts (<200 cells/mm 3 , p > 0.05). Of the women, 60% were infected in the cervix and 45% in the anal canal, with an agreement of at least one genotype in 90%. The HR-HPV types associated with HSILs were HPV66, 33, 52, 51, 45, 18, and 68.

Objective: To analyze the presenceof human papillomavirus in prostate and its associationwith prostate cancer. METHODS: A case-control study was conducted.Tissue samples with benign hyperplasia and prostatecancer were collected. Risk factors related to prostatecancer and human papillomavirus were assessedby a medical interview. Prostate tissue was obtainedby transrectal biopsy or transurethral resection. Theidentification of viral genome was assessed by the amplificationof 450 pb., from L1 gene. Real time PCR wasused to identified HPV genotypes 16 and 18. For dataanalysis, the χ2 test, Student's T test or Mann-WhitneyU test and OR were computed. RESULTS: Thirty and 99 with benign prostatehyperplasia were included in a 1:3 ratio, with a meanage of 69.44±9.22 years. The global prevalence of humanpapillomavirus was 15.2% being similar in bothcases (15.6%) and controls (15.1%) with no significantdifference (p = 0.572). Forty percent of the infectionswere persistent. From all positive samples, only in the40% were identified some of the genotypes analyzed(16 and 18). The group of patients with Gleason scorede > 7 had a virus prevalence of 16%., Conclusions: The results show the presence ofthe human papillomavirus genome in prostate tissuewith and without neoplasia; no association was foundbetween infection and prostate cancer.

Human papillomavirus type 13 (HPV13) is a low-risk HPV type associated with Multifocal Epithelial Hyperplasia (MEH). It is considered a rare pathology of oral mucosa, more prevalent in certain ethnical groups, such as the Maya from Yucatan in Mexico. As for 2020 only two complete genomes of HPV13 are publicly available in Genbank database (one from Turkey one from the Amazonian). We aimed to obtain the complete genome sequence of HPV13 associated to MEH, obtained from a community in the Mayan area from Mexico. A bank of oral swabs from children with MEH were used. To enrich the sample, a Rolling Cycle Amplification (RCA) method was performed followed by overlapping end-point PCR of 500 bp fragments, Sanger sequencing and assembly. Eight open reading frames (ORFs) were annotated (E1, E2, E4, E5, E6, E7, L1 and L2 genes). When compared with the other two previously reported genomes the identity at nucleotide level is high 98.9% and 99.6%, respectively. The phylogenetic tree shows that Yucatan HPV13 is more closely related to HPV13 obtained from the Amazonian. Most changes identified at amino acid level are substitutions derived from nucleotide variations or SNPs in coding regions. Amino-acid changes were observed in E2 and E1 proteins (n ≥ 8), and in L1, L2, E6 and E5 proteins (n ≤ 5). E7 protein from Yucatan has 100% identity with the reported from Amazonian and differs (94.1% identity) with the one from Turkey due to 3 substitutions and three missing amino acids. In conclusion, the genome from HPV13 (7831 bp, 49 nt missing) associated to MEH in the Mayan area from Yucatan was obtained from stored swabs; this is the first effort in Mexico, the second in Latin America, and the third of the world. More research that contributes to the knowledge of the determinants underlying this neglected pathology are urged., (Copyright © 2020 Elsevier B.V. All rights reserved.)

As for 2020 only two complete genomes of Human papillomavirus type 13 (HPV13) are publicly available in GenBank database. In addition, reports of partial sequences of genetic regions are very limited. Therefore, genomic research that contributes to knowledge of viral components involved in HPV13 pathogenesis, and molecular mechanisms associated to multifocal epithelial hyperplasia (MEH) disease are urged. In the accompanying paper [1], we aimed to obtain the complete genome sequence of HPV13 associated to MEH disease, obtained from a Mayan boy living in Yucatan, Mexico. Coding sequences were annotated, and viral proteins traduced and deposited in GenBank with accession number MT068446. In this data report, we present the oligonucleotide list used to amplify the complete genome, a graphical abstract of process employed for the amplification of circular HPV13 genome, a representative figure of PCR products obtained for sequencing and multiple sequence alignments with the translated coding sequences of the existing genomes: X62843 is the first HPV13 genome reported [2]; it was generated from a clone obtained from a Turkish patient; DQ344807 was originally obtained from a patient in the Amazonian region [3]. The multiple sequence alignments show the main viral proteins (predicted). This provides relevant information for future molecular analysis and epidemiological studies because HPV13 is an understudied genotype associated to a neglected disease that appears more commonly in children. Additionally, the description of the methods can help in future sequencing of HPV genomes. We hope that our solutions will help researchers who do not have next-generation sequencing (NGS) platforms. A more comprehensive analysis of this data may be obtained from "Genomic characterization of Human papillomavirus type 13, associated to Multifocal Epithelial Hyperplasia, in a Mayan community" [1]., Competing Interests: The authors declare that they have no known competing financial interests or personal relationships which have, or could be perceived to have, influenced the work reported in this article., (© 2021 The Authors.)

Introduction: Human cytomegalovirus (HCMV) is recognized as the most common cause of congenital viral infection, which can occur as a result of primary infection, reinfection or infection reactivation in the pregnant woman and be the cause of delay in neuronal development and sensorineural hearing loss in the neonate., Objective: To identify CMVH infection in newborns by real-time polymerase chain reaction (RT-PCR) and cell culture., Method: Observational, cross-sectional, retrospective study with oral swab samples from 362 neonates born within a 10-month period in a public hospital of Mérida, Yucatán. RT-PCR was carried out for the detection of HCMV. Fibroblast primary cell culture was obtained from human foreskin tissue to isolate the virus. Only positive cases were followed., Results: A prevalence of HCMV infection of 0.86 % was found by RT-PCR. No virus was isolated with cell culture. In the follow-up visits, sensory health and neurodevelopment were adequate., Conclusion: The prevalence of HCMV infection is similar to that of worldwide reports, and only was detected by RT-PCR. Asymptomatic infection detected 12-14 h after birth had no long-term health consequences., (Copyright: © 2019 Permanyer.)

Background: High-risk human papillomaviruses (HR-HPV) infection has been associated with 90% of anal cancer cases. Women with abnormal cytology are a high-risk group to develop anal neoplasia. The aim of this study is to describe the prevalence and epidemiology of HR-HPV 16, 18, 45, and 58 anal infections in women with cervical abnormalities, as well as to assess E2 gene integrity., Methods: A cross-sectional study was performed on 311 cervical and 311 anal samples from patients with abnormal cytology in two colposcopy clinics in Yucatan, Mexico. A specific PCR for oncogenes was performed in order to identify HVP 16, 18, 45 and 58. Real time PCR was used to amplify the whole HPV 16, 18, and 58 E2 gene to verify its integrity in anal samples., Results: High risk HPV 16, 18, 58, and/or 45 were found in 41.47% (129/311) of cervical samples, and in 30.8% (96/331) of anal samples, with 18% (57/311) of the patients being positive in both samples. The same genotypes in both anatomical sites were observed in 11.25% (35/311). The E2 gene was disrupted in 82% of all tested samples. The frequency of genome disruption viral integration in anal samples by genotype was: HPV 58 (97.2%); HPV 16 (72.4%), and HPV 18 (0%)., Conclusion: Women with cervical disease have HR-HPV anal infections, and most of them have the E2 gene disrupted, which represents a risk to develop anal cancer., (Copyright © 2016 Elsevier España, S.L.U. and Sociedad Española de Enfermedades Infecciosas y Microbiología Clínica. All rights reserved.)

Background: HPV infection is the most common sexually transmitted viral infection, and is associated with several neoplasms., Aim: To describe the epidemiology, natural history and risk factors associated with oral HPV infection in asymptomatic young adults., Methods: A prospective and longitudinal study was conducted, including subjects without oral pathology, who were sampled from the oral mucosa. All subjects with positive results were re-sampled 6 months later. The presence of HPV was identified by PCR. Demographic and sexual behavior data were obtained with a survey that was responded without the intervention of the researcher., Results: 102 samples were collected from subject of 18-26 years old, 60 (58.8%) were male. The prevalence of the virus was 6.9%; all positive subjects had active sexual life. Same-gender relationships were the only variable associated with the presence of the virus (p < 0.05). At six months all subjects had eliminated the virus., Conclusion: Oral HPV infection is transient and is associated to same-gender relationships, mainly women who have sex with women.

Context: Human papillomavirus (HPV) and Chlamydia trachomatis are the most frequent sexually transmitted infections, usually asymptomatic. Persistent infection with high-risk HPV types and other cofactors such as the concomitant infection with C. trachomatis can represent a higher risk to develop cervical lesions; therefore, screening with sensitive methods could aid to identify women at risk., Aims: The aim is to determine the prevalence and concurrence of both infections, detected with in-house molecular methods, and to identify the risk factors associated to the infections in Mexican women., Subjects and Methods: This was a cross-sectional study including gynaecological-obstetrical medical outpatients from a Social Security Hospital in Southeast Mexico. After informed consent, cervicovaginal samples were collected and tested for HPV and C. trachomatis using polymerase chain reaction (PCR). HPV positives were further tested for high-risk HPV16, 18, 58 and low-risk 11 using real-time PCR. All methods employed were in-house. Data analyses included odds ratios (OR), Chi-square and linear regressions., Results: Women included were 233, aging 15-49 (mean 30 years), 52.8% were pregnant. For HPV and C. trachomatis testing, 230 samples were adequate, resulting in 48 (20.9%) and 15 (6.5%) positives, respectively; 4 (1.7%) were positive to both. The most frequent genotype identified was HPV58 (25% of typified samples). C. trachomatis positives were 73% asymptomatic, none had pelvic inflammatory disease or infertility histories. The only variable associated to HPV infection was the history of previous sexually transmitted disease (OR = 3.69,P= 0.0019)., Conclusions: More than 25% of the population was infected with either agent. We successfully used in-house molecular methodologies for diagnosis and typing, showing HPV and C. trachomatis prevalence consistent to previous reports. Concomitant infections were found, HPV high-risk types were involved in half of these cases, representing a higher risk.

Integration of human papillomavirus (HPV) DNA into human cells accompanied by the disruption of the viral genome has been described as a prerequisite for cancer development. This study aimed to investigate E2 gene integrity of HPV16 and HPV58 viruses isolated from infected women with cervical lesions. Forty-two HPV16- and 31 HPV58-positive samples were analysed. E2 integrity was assumed when all fragments covering the E2 gene were amplified with specific polymerase chain reaction primers. Overall, in 59% of the samples, at least one fragment was not amplified in HPV16- (57%) and HPV58-positive samples (61%). Samples from high-grade squamous intraepithelial lesions had the highest frequency of E2 gene disruptions (73%), followed by samples from low-grade squamous intraepithelial lesions (63%) and, finally, samples from invasive cervical cancer (35%). Association between the integrity status of the E2 gene, and lesion grade was assessed by the chi-squared test applied to the combined set of viruses (p = 0.6555) or to populations of the same virus type (HPV58, p = 0.3101; HPV16, p = 0.3024). In conclusion, in this study, no association was found between the presence of E2 gene disruptions and the grade of cervical lesions caused by HPV16 and HPV58.

High-risk human papillomaviruses (HR-HPV) are considered necessary for the development of cervical cancer. Furthermore, there is no doubt that some types of oral squamous cell carcinoma are associated with HR-HPV. The epidemiology of oral HPV infections in healthy subjects remains unclear due to a lack of knowledge. The objective of this study was to investigate the epidemiology of human papillomavirus infections of the oral mucosa without pathology. A cross-sectional study was performed; samples from 390 women seeking prenatal care, Pap smears, family planning or gynecological diseases were studied. Oral cells were collected by direct swab sampling. Information regarding sociodemographic status, sexual behavior, infectious diseases, contraceptive history and tobacco and alcohol consumption were obtained through direct interviews. HPV and genotypes were detected by type-specific polymerase chain reaction. Our results revealed that 14% of the women studied had an oral HPV infection. Women ≤ 20 years of age had the highest HPV prevalence (24.5%). In total, seven genotypes were identified, including the high-risk genotypes 16, 18, 58 and 59 and the low-risk genotypes 6, 81 and 13, the latter of which is a type exclusive to oral mucosa. Sexual behavior was not associated with the presence of genital HPV types in the oral mucosa. Genital HPV types were present in the oral mucosa of women without associated clinical manifestations; however, sexual behavior was not associated with infection, and therefore others routes of transmission should be explored.

Objective: To investigate if HPV cervical infection is associated with spontaneous abortion in a Mexican population., Study Design: Case control study including 281 women from two Social Security Hospitals in Merida, Mexico. Cases were women with spontaneous abortion attending for curettage, and controls were pregnant women at term who attended for delivery. HPV molecular detection and typing of HPV 16, 18, 58 and 6/11 was performed on cervical samples, and TORCH serology IgM tests (against T. gondii, CMV, HSV) were performed on cases. Data were analyzed using Chi square, odds ratio and linear regression tests., Results: HPV global prevalence was 19.8% (24.4% in cases and 15.2% in controls). HPV types 16 and 58 were the most frequently detected in both groups. Multiple HPV types concurrent infection were found in 31.4% of typified samples. Amongst cases 27.3% of HPV positive women reported at least one previous pregnancy loss; compared to 17.43% amongst HPV negative women. Nevertheless, HPV was not significantly associated with spontaneous or to repetitive abortion. Cases were 60.2% positive to any TORCH agent, although it was not significantly associated to referred miscarriage history. Spontaneous abortion was associated to a previous pregnancy loss and to women's age older than 35 years old. HPV infection was significantly associated to alcohol intake before pregnancy and to multiple sexual partners., Conclusion: HPV cervical infection was not associated with spontaneous abortion. HPV in spontaneous abortion and other adverse pregnancy outcomes merits further study., (Copyright © 2013 Elsevier Ireland Ltd. All rights reserved.)

Multifocal epithelial hyperplasia (MEH) is a disease of the oral mucosa. Human papillomaviruses 13 and 32 have been detected in these lesions. We describe the epidemiology and clinical characteristics of patients with MEH in a rural community in the Mayan area of Mexico with 53 cases and 54 controls. Clinical and epidemiological data were collected through a direct interview. Oral cell samples were collected with a cytobrush. Subjects collected their own saliva sample in a sterile bottle. All samples were tested for HPV 13 and 32 by polymerase chain reaction using specific primers. Of the 53 patients and 54 healthy subjects, 56% were < 12 years old, 25% were males and 75% females. Evolution of the lesions was between two months and 17 years. The lesions affected lips, jugal mucosa, and tongue, 96% had multiple lesions. From 53 patients, fifty samples of oral cells and 31 samples of saliva were analyzed. HPV 13 was detected in 100% oral cell and 100% saliva samples studied. 16 healthy subjects were HVP 13 positive. A highly significant association of HPV 13 infection and MEH was found, as determined by chi square test (p = 0.00) Household transmission of HPV 13 may happen through saliva and the shared use of contaminated objects.

Background: Multifocal epithelial hyperplasia is a pathology of the oral mucosa which has been reported in diverse ethnic groups. Human papillomavirus (HPV) types 13 and 32 DNA has been detected in these lesions. The aims of this paper are to describe the epidemiological and clinical characteristics of an outbreak in a rural community in the Mayan area of Mexico and to identify a possible route of transmission through saliva., Methods: A cross-sectional study was conducted in Chemax (Yucatan, Mexico). Clinical and epidemiological data were obtained through direct interviews. Samples of oral cells and saliva were taken. HPV 13 and 32 were identified by polymerase chain reaction using specific primers., Results: A total of 57 patients were studied, of whom 79.1% were aged <15 years, 38.6% were male, and 61.3% were female. The duration of lesions ranged from one month to 50 years. Lesions were located on the lips, jugal mucosa, and more frequently, the tongue. HPV 13 was found in all the patients and HPV 32 in none. A total of 42 saliva samples were positive for HPV 13., Conclusions: Human papillomavirus type 13 is involved in multifocal epithelial hyperplasia among the Mexican Mayan population. The presence of HPV 13 in cells from saliva, combined with poor hygiene behaviors, may explain the familial distribution of the pathology., (© 2011 The International Society of Dermatology.)

Infection with some genotypes of human papillomavirus (HPV) is the most important risk factor associated with cervical cancer (CC). Throughout the world, HPV type 58 prevalence varies from one region to another; it is higher in women from certain countries in Asia and Latin America, such as China and Mexico. Although intratypic variants have been reported on a few occasions, our knowledge about HPV 58 genetic variation remains limited. Therefore, this work aims to (i) determine the prevalence of HPV type 58 amongst Mexican women with invasive CC or precursor lesions and (ii) identify HPV 58 sequence variants. One hundred and forty five colposcopy clinic patients were studied. Genotyping of HPV 16, 18 and 58 was determined by specific nested PCR and HPV 58 variants were detected by direct sequencing. The general prevalence of HPV was 51.7% (75/145). HPV 16 was found in 30.6% (23/75) and HPV 58 in 24% (18/75) of the patients. HPV 18 was not identified in patients with cervical intraepithelial neoplasia (CIN) grade I; it was only found in those with CIN II, with a prevalence of 6.8% (3/44). In patients with CC, the prevalence of HPV 16 and 58 was 78.9%. Regarding HPV 58 variants, 94.4% of the HPV 58 sequences were identical to the prototype strain, whereas one sample showed changes at a single nucleotide. This study demonstrates a high prevalence of HPV 58 and a low genetic variability of E6 sequences amongst Mexican colposcopy patients.

A genetic linkage map of the fungal plant pathogen Mycosphaerella fijiensis, causal agent of black leaf streak disease of banana was developed. A cross between the isolates CIRAD86 (from Cameroon) and CIRAD139A (from Colombia) was analyzed using molecular markers and the MAT locus. The genetic linkage map consists of 298 AFLP and 16 SSR markers with 23 linkage groups, containing five or more markers, covering 1,879 cM. Markers are separated on average by around 5.9 cM. The MAT locus was shown to segregate in a 1:1 ratio but could not be successfully mapped. An estimate of the relation between physical size and genetic distance was approximately 39.0 kb/cM. The estimated total haploid genome size was calculated using the genetic mapping data at 4,298.2 cM. This is the first genetic linkage map reported for this important foliar pathogen of banana. The great utility of the map will be for anchoring contigs in the genome sequence, evolutionary studies in comparison with other fungi, to identify quantitative trait loci (QTLs) associated with aggressiveness or oxidative stress resistance and with the recently available genome sequence, for positional cloning.

Invasive fungal infections of the respiratory tract are a major cause of serious morbidity and mortality especially in immunocompromised patients due to neutropenia, corticosteroids, or hematologic malignancy. The role of imaging is very important in the management of patients with fungal infections and chest x-ray is still the most used exploration. Nevertheless, new approaches recommend the systematic use of computed tomography scan for early documentation of invasive fungal infection. Combination of clinical setting with recognition of radiological pattern is the best approach to pulmonary fungal diseases. The following is a review of the imaging features of different invasive fungal infections we can face in our daily practice.

A bacterial artificial chromosome library of the causal agent of the Black Sigatoka leaf spot disease of banana and plantain, Mycosphaerella fijiensis, has been constructed using a non-sphaeroplasting technique and characterized using both homologous and heterologous probes. After first and a second size selection of PFGE-fractionated DNA, a ligation was obtained using a 1:4 molar ratio (insert:vector). One hundred random clones were analyzed, and the mean insert size was estimated to be 90 kb. The range of the insert sizes was between 40 and 160 kb. The highest percentage of inserts belonged to the range between 80 and 100 kb; 32% of the inserts had 2 or 3 internal NotI sites. This library consists of 1920 clones, if the genomic size is at least 35 Mb, then this represents 4.9 x genome equivalents, which was supported by hybridization results with homologous and heterologous probes.

SUMMARY Idiomorphs mat1-1 and mat1-2 from Mycosphaerella fijiensis, the causal agent of black leaf streak disease of banana, were isolated. Degenerate oligos were used to amplify the HMG box of the mat1-2 idiomorph from M. fijiensis, showing homology with the HMG box of Mycosphaerella graminicola. Using a DNA walking strategy, anchored on the DNA lyase gene towards the HMG box, a 9-kb-long region of mat1-2 was obtained. A 5-kb fragment from the mat1-1 region was obtained by long-range PCR using primers on the flanking regions, which have close to 100% identity between both idiomorphs. High-identity (77-89%), inverted regions within both idiomorphs were found, which suggest unique inversion events, which have not been found before, and that could have been significant in the evolution of this species. The predicted genes showed the conserved introns in both idiomorphs as well as an additional intron within the alpha box. The implications for the evolution of species in the Mycosphaerella complex on banana are discussed.