Microbiología y RT-PCR

Determination of low bacterial concentrations in hyperarid Atacama soils: comparison of biochemical and microscopy methods with real-time quantitative PCR.

Fletcher LE1, Conley CA, Valdivia-Silva JE, Perez-Montaño S, Condori-Apaza R, Kovacs GT, Glavin DP, McKay CP.

¹Atmospheric, Oceanic, and Planetary Physics, Clarendon Laboratory, University of Oxford, UK. Lauren@atm.ox.ac.uk

 

Abstract

Hyperarid Atacama soils are reported to contain significantly reduced numbers of microbes per gram of soil relative to soils from other environments. Molecular methods have been used to evaluate microbial populations in hyperarid Atacama soils; however, conflicting results across the various studies, possibly caused by this low number of microorganisms and consequent biomass, suggest that knowledge of expected DNA concentrations in these soils becomes important to interpreting data from any method regarding microbial concentrations and diversity. In this paper we compare the number of bacteria per gram of Atacama Desert soils determined by real-time quantitative polymerase chain reaction with the number of bacteria estimated by the standard methods of phospholipids fatty acid analysis, adenine composition (determined by liquid chromatography - time-of-flight mass spectrometry), and SYBR-green microscopy. The number determined by real-time quantitative polymerase chain reaction as implemented in this study was several orders of magnitude lower than that determined by the other three methods and probably underestimates the concentrations of soil bacteria, most likely because of soil binding during the DNA extraction methods. However, the other methods very possibly overestimate the bacteria concentrations owing to desiccated, intact organisms, which would stain positive in microscopy and preserve both adenine and phospholipid fatty acid for the other methods.

Can J Microbiol. 2011 Nov;57(11):953-63. doi: 10.1139/w11-091.

http://www.nrcresearchpress.com/doi/abs/10.1139/w11-091?url_ver=Z39.88-2003&rfr_id=ori%3Arid%3Acrossref.org&rfr_dat=cr_pub%3Dpubmed&#.VbJdMkWdMnU

Md PhD Julio Valdivia Silva. Fundador del GII

Enfermedad Inflamatoria Pélvica

Limitations of the criteria used to diagnose histologic endometritis in epidemiologic pelvic inflammatory disease research.

Vicetti Miguel RD¹, Chivukula M, Krishnamurti U, Amortegui AJ, Kant JA, Sweet RL, Wiesenfeld HC, Phillips JM, Cherpes TL.

¹University of Pittsburgh School of Medicine, Department of Pediatrics, PA 15224, USA.

 

Abstract

While endometrial neutrophils and plasma cells are criteria used to diagnose histologic endometritis in epidemiologic pelvic inflammatory disease (PID) research, plasma cell misidentification and nonspecificity may limit the accuracy of these criteria. Herein, we examined: (1) the identification of endometrial plasma cells with conventional methyl green pyronin-based methodology versus plasma cell-specific (CD138) immunostaining, (2) the prevalence of endometrial plasma cells among women at low risk for PID, and (3) endometrial leukocyte subpopulations among women diagnosed with acute or chronic histologic endometritis by conventional criteria. We observed an absence of CD138+ cells in 25% of endometrial biopsies in which plasma cells had been identified by conventional methodology, while additional immunohistochemical analyses revealed indistinguishable inflammatory infiltrates among women diagnosed with acute or chronic endometritis by conventional criteria. Among women considered at lower risk for PID development, flow cytometric analyses detected plasma cells in 30% of endometrial biopsy specimens, suggesting that these cells, even when accurately identified, only nonspecifically identify upper genital tract inflammatory processes. Combined, our findings underscore the limitations of the criteria used to diagnose histologic endometritis in PID-related research and suggest that satisfactory understanding of PID pathogenesis, treatment, and prevention is hindered by continued use of these criteria.

Copyright © 2011 Elsevier GmbH. All rights reserved.

Pathol Res Pract. 2011 Nov 15;207(11):680-5. doi: 10.1016/j.prp.2011.08.007. Epub 2011 Oct 13.

http://www.sciencedirect.com/science/article/pii/S0344033811002044

Md. Rodolfo Vicetti. Ex-miembro del GII.

Chlamydia trachomatis e Inmunidad

Chlamydia trachomatis infection control programs: lessons learned and implications for vaccine development.

Chavez JM¹, Vicetti Miguel RD, Cherpes TL.

¹Department of Pediatrics, University of Pittsburgh School of Medicine, Rangos Research Center, Room 9123, 4401 Penn Avenue, Pittsburgh, PA 15224, USA.

 

Abstract

Chlamydia trachomatis control efforts that enhance detection and treatment of infected women may paradoxically increase susceptibility of the population to infection. Conversely, these surveillance programs lower incidences of adverse sequelae elicited by genital tract infection (e.g., pelvic inflammatory disease and ectopic pregnancy), suggesting enhanced identification and eradication of C. trachomatis simultaneously reduces pathogen-induced upper genital tract damage and abrogates formation of protective immune responses. In this paper, we detail findings from C. trachomatis infection control programs that increase our understanding of chlamydial immunoepidemiology and discuss their implications for prophylactic vaccine design.

Infect Dis Obstet Gynecol. 2011;2011:754060. doi: 10.1155/2011/754060. Epub 2011 Nov 14.

http://www.hindawi.com/journals/idog/2011/754060/

Md. Rodolfo Vicetti. Ex-miembro del GII.

Infecciones del Tracto Genital

Endometrial leukocyte subpopulations associated with Chlamydia trachomatis, Neisseria gonorrhoeae, and Trichomonas vaginalis genital tract infection.

Reighard SD¹, Sweet RL, Vicetti Miguel C, Vicetti Miguel RD, Chivukula M, Krishnamurti U, Cherpes TL.

¹Department of Pediatrics, University of Pittsburgh School of Medicine, Pittsburgh, PA 15224, USA.

 

Abstract

OBJECTIVE:

The objective of the study was to characterize endometrial inflammation associated with common genital tract pathogens.

STUDY DESIGN:

The design of the study was the immunohistochemical characterization of the endometrial leukocyte subpopulations from 37 controls and 45 women infected with Chlamydia trachomatis, Neisseria gonorrhoeae, or Trichomonas vaginalis.

RESULTS:

Compared with uninfected women, endocervical infection with C trachomatis, N gonorrhoeae, or T vaginalis was associated with significant increases in endometrial T cells, B cells, plasma cells, and polymorphonuclear leukocytes. Even more substantial increases in T cell, B cell, and plasma cell numbers were detected among women infected endocervically and endometrially with C trachomatis.

CONCLUSION:

Because lower genital tract C trachomatis, N gonorrhoeae, or T vaginalis infections were associated with comparable increases in the same endometrial leukocyte subpopulations, our results suggest the underappreciated involvement of T vaginalis in upper genital tract inflammatory processes. The more robust inflammatory infiltrate associated with C trachomatis endometrial ascension may offer insight into host inflammatory responses associated with pelvic inflammatory disease development.

Copyright © 2011 Mosby, Inc. All rights reserved.

Am J Obstet Gynecol. 2011 Oct;205(4):324.e1-7. doi: 10.1016/j.ajog.2011.05.031. Epub 2011 May 20.

http://www.sciencedirect.com/science/article/pii/S0002937811006594

Md. Rodolfo Vicetti. Ex-miembro del GII.

Dieta y Sindrome Premenstrual

Dietary B vitamin intake and incident premenstrual syndrome.

Chocano-Bedoya PO¹, Manson JE, Hankinson SE, Willett WC, Johnson SR, Chasan-Taber L, Ronnenberg AG, Bigelow C, Bertone-Johnson ER.

¹Department of Public Health, School of Public Health and Health Sciences, University of Massachusetts, Amherst, MA 01003-9304, USA.

 

Abstract

BACKGROUND:

Thiamine, riboflavin, niacin, vitamin B-6, folate, and vitamin B-12 are required to synthesize neurotransmitters that are potentially involved in the pathophysiology of premenstrual syndrome (PMS).

OBJECTIVE:

The objective was to evaluate whether B vitamin intake from food sources and supplements is associated with the initial development of PMS.

DESIGN:

We conducted a case-control study nested within the Nurses' Health Study II cohort. Participants were free of PMS at baseline (1991). After 10 y of follow up, 1057 women were confirmed as cases and 1968 were confirmed as controls. Dietary information was collected in 1991, 1995, and 1999 by using food-frequency questionnaires.

RESULTS:

Intakes of thiamine and riboflavin from food sources were each inversely associated with incident PMS. For example, women in the highest quintile of riboflavin intake 2-4 y before the diagnosis year had a 35% lower risk of developing PMS than did those in the lowest quintile (relative risk: 0.65; 95% CI: 0.45, 0.92; P for trend = 0.02). No significant associations between incident PMS and dietary intakes of niacin, vitamin B-6, folate, and vitamin B-12 were observed. Intake of B vitamins from supplements was not associated with a lower risk of PMS.

CONCLUSIONS:

We observed a significantly lower risk of PMS in women with high intakes of thiamine and riboflavin from food sources only. Further research is needed to evaluate the effects of B vitamins in the development of premenstrual syndrome.

Am J Clin Nutr. 2011 May;93(5):1080-6. doi: 10.3945/ajcn.110.009530. Epub 2011 Feb 23.

http://ajcn.nutrition.org/content/93/5/1080.long

Md. PhD. Patricia Chocano. Ex miembro del GII.  

Cancer e inmunidad

A caveat for T cell transfer studies: generation of cytotoxic anti-Thy1.2 antibodies in Thy1.1 congenic mice given Thy1.2+ tumors or T cells.

McKenna KC¹, Vicetti Miguel RD, Beatty KM, Bilonick RA.

¹University of Pittsburgh, Eye and Ear Institute, Pittsburgh, PA 15213, USA. mckennakc@upmc.edu

 

Abstract

Thy1.1 congenic B6.PL mice were used to simultaneously monitor Thy1.2+ E.G7-OVA tumors transplanted in the a.c. of the eye and i.v.-transferred tumor-specific Thy1.2+ CTLs to determine mechanisms that inhibit the tumoricidal activity of CTL responses in mice with established ocular tumors. Transferred CTLs were systemically deleted in mice with established ocular tumors. However, this deletion was not a unique mechanism of immune evasion by ocular tumors. Rather, development of Thy1.2+ tumors in the eye or skin of B6.PL mice generated cytotoxic anti-Thy1.2 antibodies that eliminated a subsequent Thy1.2+ T cell transfer. Anti-Thy1.2 immune responses in B6.PL mice were influenced by the route of antigen administration, as the serum concentration of cytotoxic anti-Thy1.2 antibodies was 92-fold greater in mice with eye tumors in comparison with mice with skin tumors. In addition, anti-Thy1.2 immune responses were detected in B6.PL mice given naïve Thy1.2+ T cells i.p. but not i.v. Anti-Thy1.2 responses were augmented in B6.PL mice with ocular Thy1.2+ EL-4 tumors that did not express OVA, suggesting immunodominance of OVA antigen over Thy1.2. Thy1.1+ T cells given i.p. was not immunogenic in Thy1.2 congenic mice. These data reaffirm that the introduction of antigens in the a.c. induces robust antibody responses. Experimentation using allotypic differences in Thy1 between donor cells and recipient mice must consider cytotoxic anti-Thy1 antibody generation in the interpretation of results.

J Leukoc Biol. 2011 Feb;89(2):291-300. doi: 10.1189/jlb.0610333. Epub 2010 Oct 19.

http://www.jleukbio.org/content/89/2/291.long

Md. Rodolfo Vicetti. Ex-miembro del GII.