Search

Abstract Intraspecific variation in plants is expected to have profound impacts on the arthropod communities associated with them. Because sexual dimorphism in plants is expected to provide consistent variation among individuals of the same species, researchers have often studied the effect it has on associated arthropods. Nevertheless, most studies have focused on the effect of sexual dimorphism in a single or a few herbivores, thus overlooking the potential effects on the whole arthropod community. Our main objective was to evaluate effects of Buddleja cordata's plant‐sex on its associated arthropod community. We surveyed 13 pairs of male and female plants every 2 months during a year (June 2010 to April 2011). Every sampling date, we measured plant traits (water content and leaf thickness), herbivory, and the arthropod community. We did not find differences in herbivory between plant sex or through time. However, we found differences in water content through time, with leaf water‐content matching the environmental seasonality. For arthropod richness, we found 68 morphospecies associated with female and 72 with male plants, from which 53 were shared by both sexes. We did not observe differences in morphospecies richness; however, we found sex‐associated differences in the diversity of all species and differences on the diversity of the most abundant species with an interesting temporal component. During peak flowering season, male plants showed higher values on both parameters, but during the peak fructification season female plants showed the higher values on both diversity parameters. Our research exemplifies the interaction between plant‐phenology and plant‐sex as drivers of arthropod communities' diversity, even when plant sexual‐dimorphism is inconspicuous, and highlighting the importance of accounting for seasonal variation. We stress the need of conducting more studies that test this time‐dependent framework in other dioecious systems, as it has the potential to reconcile previous contrasting observations reported in the literature.

Abstract Biomarkers to identify women at risk of cervical cancer among those with high-risk HPV infection (hrHPV+) are needed. Deregulated expression of microRNAs (miRNAs) contributes to hrHPV-induced cervical carcinogenesis. We aimed at identifying miRNAs with the capacity to distinguish high (CIN2+) and low (≤ CIN1) grade cervical lesions. We sequenced miRNA libraries from Formalin-Fixed Paraffin-Embedded (FFPE) tissues from women with CIN2+ (n = 10) and age-matched women with ≤ CIN1 (n = 10), randomly and retrospectively selected from a trial that followed women for 24 months after a hrHPV+ test at the screening visit. Five miRNAs differentially expressed were validated by RT-qPCR in an independent set of FFPE tissues with a reviewed diagnosis of CIN2+ (n = 105) and ≤ CIN1 (n = 105). The Ingenuity Pathway Analysis (IPA) was conducted to identify mRNAs inversely correlated with the top 25 differentially expressed miRNAs. Inverse correlations with 401 unique mRNA targets were identified for fourteen of the top 25 differentially expressed miRNAs. Eleven of these miRNAs targeted 26 proteins of pathways deregulated by HPV E6 and E7 oncoproteins and two of them, miR-143-5p and miR-29a-3p, predicted CIN2+ and CIN3+ in the independent validation by RT-qPCR of FFPE tissues from hrHPV-positive women.

Este trabajo usa teoría de control óptimo para determinar el nivel de extracción de agua, de un acuífero, de manera racional. La función objetivo evalúa el valor presente del beneficio social neto de la explotación a lo largo del tiempo. En el beneficio intervienen la demanda y los costos de suministrar agua. La restricción representa la dinámica de la cantidad de agua en el acuífero, dependiendo de los niveles extracción y recarga. El modelo se aplica al acuífero 2411 de San Luis Potosí utilizando información empírica del consumo de agua de la población perteneciente a la zona conurbada de la capital del estado. La condición inicial se deja como parámetro para analizar la posibilidad tanto de óptimo interior como de óptimo de esquina. El óptimo interior recomienda un nivel de extracción de 42,854 miles de metros cúbicos y un precio de 0.00003658 pesos por metro cúbico de agua. El acuífero se encuentra actualmente muy sobreexplotado. Para mantener la sustentabilidad del acuífero se recomienda revisar la normativa de las tarifas y mejorar la micro medición de los consumos para construir un modelo más preciso. Abstract Optimal control theory is used to determine the level of water extraction, from an aquifer, in a rational way. The exploitation of the aquifer generates a net social benefit that represents the objective function. The benefit involves the demand and the costs of supplying water. The restriction represents the dynamics of the amount of water in the aquifer, depending on the levels of extraction and recharge. The model is calibrated with data on the 2411 aquifer of San Luis Potosi. Empirical information on water consumption of the population belonging to the metropolitan area of the state capital. The initial condition is left as a parameter in order to study the possibility of both an interior solution or a corner solution. The optimum interior recommends an extraction level of 42.854 thousand cubic meters and a price of 0.00003658 pesos per cubic meter of water. The aquifer is currently highly overexploited. To maintain the sustainability of the aquifer, it is recommended to review the tariff regulations and improve the micro measurement of consumption to build a more accurate model.

Se analiza la regulaci ́on establecida por el Banco de M ́exic o en el a ̃no 2010 en comisiones por transacciones interbancarias e n cajeros autom ́aticos. Bajo un modelo espacial duop ́olico se determ ina end ́oge- namente n ́umero de cajeros, precio por apertura de cuenta y c omisiones en cajeros. Se encuentra que las comisiones por transaccion es interban- carias permanecen sin cambios. La regulaci ́on incentiva la instalaci ́on de cajeros, lo que disminuye las ganancias de los bancos. La p rohibi- ci ́on por cobro de comisiones en cajeros propios genera que l os bancos incrementen sus precios por apertura de cuenta. Con la propu esta de una regulaci ́on alterna mostramos que la prohibici ́on en el cobro de comisiones a cuentahabientes fue el aspecto crucial que m odific ́o el equilibrio.

Intraspecific variation in plants is expected to have profound impacts on the arthropod communities associated with them. Because sexual dimorphism in plants is expected to provide consistent variation among individuals of the same species, researchers have often studied the effect it has on associated arthropods. Nevertheless, most studies have focused on the effect of sexual dimorphism in a single or a few herbivores, thus overlooking the potential effects on the whole arthropod community. Our main objective was to evaluate effects of Buddleja cordata 's plant-sex on its associated arthropod community. We surveyed 13 pairs of male and female plants every 2 months during a year (June 2010 to April 2011). Every sampling date, we measured plant traits (water content and leaf thickness), herbivory, and the arthropod community. We did not find differences in herbivory between plant sex or through time. However, we found differences in water content through time, with leaf water-content matching the environmental seasonality. For arthropod richness, we found 68 morphospecies associated with female and 72 with male plants, from which 53 were shared by both sexes. We did not observe differences in morphospecies richness; however, we found sex-associated differences in the diversity of all species and differences on the diversity of the most abundant species with an interesting temporal component. During peak flowering season, male plants showed higher values on both parameters, but during the peak fructification season female plants showed the higher values on both diversity parameters. Our research exemplifies the interaction between plant-phenology and plant-sex as drivers of arthropod communities' diversity, even when plant sexual-dimorphism is inconspicuous, and highlighting the importance of accounting for seasonal variation. We stress the need of conducting more studies that test this time-dependent framework in other dioecious systems, as it has the potential to reconcile previous contrasting observations reported in the literature., Competing Interests: On behalf of all the co‐authors, we declare that authors of the manuscript entitled: Host‐plant sex and phenology of Buddleja cordata Kunth interact to influence arthropod communities have no conflict of interest to publish this manuscript., (© 2024 The Author(s). Ecology and Evolution published by John Wiley & Sons Ltd.)

Metastasis remains the leading cause of mortality in prostate cancer patients. The presence of tumor cells in lymph nodes is an established prognostic indicator for several cancer types, such as melanoma, breast, oral, pancreatic, and cervical cancers. Emerging evidence highlights the role of microRNAs enclosed within extracellular vesicles as facilitators of molecular communication between tumors and metastatic sites in the lymph nodes. This study aims to investigate the potential diagnostic utility of EV-derived microRNAs in liquid biopsies for prostate cancer. By employing microarrays on paraffin-embedded samples, we characterized the microRNA expression profiles in metastatic lymph nodes, non-metastatic lymph nodes, and primary tumor tissues of prostate cancer. Differential expression of microRNAs was observed in metastatic lymph nodes compared to prostate tumors and non-metastatic lymph node tissues. Three microRNAs (miR-140-3p, miR-150-5p, and miR-23b-3p) were identified as differentially expressed between tissue and plasma samples. Furthermore, we evaluated the expression of these microRNAs in exosomes derived from prostate cancer cells and plasma samples. Intriguingly, high Gleason score samples exhibited the lowest expression of miR-150-5p compared to control samples. Pathway analysis suggested a potential regulatory role for miR-150-5p in the Wnt pathway and bone metastasis. Our findings suggest EV-derived miR-150-5p as a promising diagnostic marker for identifying patients with high-grade Gleason scores and detecting metastasis at an early stage.

Bisphenol A (BPA) is a ubiquitous synthetic compound used as a monomer in the production of polycarbonate plastics and epoxy resins. Even at low doses, BPA has been associated with the molecular progression of diseases such as obesity, metabolic syndrome, and hormone-regulated cancers due to its activity as an endocrine-disrupting chemical (EDC). Consequently, the use of BPA has been regulated worldwide by different health agencies. BPA structural analogs such as bisphenol S and bisphenol F (BPS and BPF) have emerged as industrial alternatives, but their biological activity in the molecular progression of cancer remains unclear. Prostate cancer (PCa) is a hormone-dependent cancer, and the role of BPA structural analogs in PCa progression is still undescribed. In this work, we use an in vitro model to characterize the transcriptomic effect of low-concentration exposure to bisphenol A, S, or F in the two main stages of the disease: androgen dependency (LNCaP) and resistance (PC-3). Our findings demonstrated that the low concentration exposure to each bisphenol induced a differential effect over PCa cell lines, which marks the relevance of studying the effect of EDC compounds through all the stages of the disease.

Prostate cancer (PCa) ranks second in incidence and sixth in deaths globally. The treatment of patients with castration-resistant prostate cancer (CRPC) continues to be a significant clinical problem. Emerging evidence suggests that prostate cancer progression toward castration resistance is associated with paracrine signals from the stroma. SFRP1 is one of the extracellular proteins that modulate the WNT pathway, and it has been identified as a mediator of stromal epithelium communication. The WNT pathway is involved in processes such as cell proliferation, differentiation, cell anchoring, apoptosis, and cell cycle regulation as well as the regulation of stem cell populations in the prostatic epithelium. In the present study, we explored the role of exogenous SFRP1 on the stem cell phenotype in prostate cancer. The results reveal that cancer stem cell markers are significantly increased by exogenous SFRP1 treatments, as well as the downstream target genes of the Wnt/-catenin pathway. The pluripotent transcription factors SOX2, NANOG, and OCT4 were also up-regulated. Furthermore, SFRP1 promoted prostate cancer stem cell (PCSC) properties in vitro , including tumorsphere formation, migration, bicalutamide resistance, and decreased apoptosis. Taken together, our results indicate that SFRP1 participates in the paracrine signaling of epithelial cells, influencing them and positively regulating the stem cell phenotype through deregulation of the WNT/β-catenin pathway, which could contribute to disease progression and therapeutic failure. This research increases our molecular understanding of how CRPC progresses, which could help us find new ways to diagnose and treat the disease., Competing Interests: The authors declare that the research was conducted in the absence of any commercial or financial relationships that could be construed as a potential conflict of interest., (Copyright © 2023 Losada-García, Salido-Guadarrama, Cortes-Ramirez, Cruz-Burgos, Morales-Pacheco, Vazquez-Santillan, Rodriguez-Martinez, González-Ramírez, Gonzalez-Covarrubias, Perez-Plascencia and Rodríguez-Dorantes.)

Despite of the capacity that several drugs have for specific inhibition of the androgen receptor (AR), in most cases, PCa progresses to an androgen-independent stage. In this context, the development of new targeted therapies for prostate cancer (PCa) has remained as a challenge. To overcome this issue, new tools, based on nucleic acids technology, have been developed. Aptamers are small oligonucleotides with a three-dimensional structure capable of interacting with practically any desired target, even large targets such as mammalian cells or viruses. Recently, aptamers have been studied for treatment and detection of many diseases including cancer. In PCa, numerous works have reported their use in the development of new approaches in diagnostics and treatment strategies. Aptamers have been joined with drugs or other specific molecules such as silencing RNAs (aptamer-siRNA chimeras) to specifically reduce the expression of oncogenes in PCa cells. Even though these studies have shown good results in the early stages, more research is still needed to demonstrate the clinical value of aptamers in PCa. The aim of this review was to compile the existing scientific literature regarding the use of aptamers in PCa in both diagnosis and treatment studies. Since Prostate-Specific Membrane Antigen (PSMA) aptamers are the most studied type of aptamers in this field, special emphasis was given to these aptamers.

Air pollution has been recognized as a global health problem, causing around 7 million deaths worldwide and representing one of the highest environmental crises that we are now facing. Close to 30% of new lung cancer cases are associated with air pollution, and the impact is more evident in major cities. In this review, we summarize and discuss the evidence regarding the effect of particulate matter (PM) and its impact in carcinogenesis, considering the "hallmarks of cancer" described by Hanahan and Weinberg in 2000 and 2011 as a guide to describing the findings that support the impact of particulate matter during the cancer continuum.

Background and Aims: Large clades of angiosperms are often characterized by diverse interactions with pollinators, but how these pollination systems are structured phylogenetically and biogeographically is still uncertain for most families. Apocynaceae is a clade of >5300 species with a worldwide distribution. A database representing >10 % of species in the family was used to explore the diversity of pollinators and evolutionary shifts in pollination systems across major clades and regions., Methods: The database was compiled from published and unpublished reports. Plants were categorized into broad pollination systems and then subdivided to include bimodal systems. These were mapped against the five major divisions of the family, and against the smaller clades. Finally, pollination systems were mapped onto a phylogenetic reconstruction that included those species for which sequence data are available, and transition rates between pollination systems were calculated., Key Results: Most Apocynaceae are insect pollinated with few records of bird pollination. Almost three-quarters of species are pollinated by a single higher taxon (e.g. flies or moths); 7 % have bimodal pollination systems, whilst the remaining approx. 20 % are insect generalists. The less phenotypically specialized flowers of the Rauvolfioids are pollinated by a more restricted set of pollinators than are more complex flowers within the Apocynoids + Periplocoideae + Secamonoideae + Asclepiadoideae (APSA) clade. Certain combinations of bimodal pollination systems are more common than others. Some pollination systems are missing from particular regions, whilst others are over-represented., Conclusions: Within Apocynaceae, interactions with pollinators are highly structured both phylogenetically and biogeographically. Variation in transition rates between pollination systems suggest constraints on their evolution, whereas regional differences point to environmental effects such as filtering of certain pollinators from habitats. This is the most extensive analysis of its type so far attempted and gives important insights into the diversity and evolution of pollination systems in large clades.

Oral squamous cell carcinoma (OSCC) is a category of aggressive malignancies that represent clinically, molecularly, and etiologically heterogeneous tumors. The majority of OSCCs are associated with tobacco and alcohol use, acting both independently and synergistically, which suggests that the environment plays an important role in carcinogenesis; however, the mechanisms associated with the development of OSCC are not well understood. It has been proposed that the epigenetic components could be implicated in the initiation and progression of OSCC. Primarily, aberrant DNA methylation patterns have been widely addressed in the study of OSCC. Diverse studies have proposed that other epigenetic processes such as post-translational histone modification, the deposition of histone variants, histone chaperones, and recently non-coding RNA, can be also involved in the development of oral cancer. In this review we focus on describing the new insights of the epigenetics processes that are related with OSCC as histones variants and long non-coding RNAs., (Copyright © 2014 Elsevier Ltd. All rights reserved.)

The exposure to particulate matter with a mean aerodynamic diameter ≤10 μm (PM10) from urban zones is considered to be a risk factor in the development of cancer. The aim of this work was to determine if PM10 exposure induces factors related to the acquisition of a neoplastic phenotype, such as cytoskeletal remodeling, changes in the subcellular localization of p21(CIP1/WAF1), an increase in β-galactosidase activity and changes in cell cycle. To test our hypothesis, PM10 from an industrial zone (IZ) and a commercial zone (CZ) were collected, and human adenocarcinoma lung cell cultures (A549) were exposed to a sublethal PM10 concentration (10 μg/cm(2)) for 24 h and 48 h. The results showed that PM10 exposure induced an increase in F-actin stress fibers and caused the cytoplasmic stabilization of p21(CIP1/WAF1) via phosphorylation at Thr(145) and Ser(146) and the phosphorylation of ERK1/2 on Thr(202). Changes in the cell cycle or apoptosis were not observed, but an increase in β-galactosidase activity was detected. The PM10 from CZ caused more dramatic effects in lung cells. We conclude that PM10 exposure induced cytoplasmic p21(CIP1/WAF1) retention, ERK1/2 activation, cytoskeleton remodeling and the acquisition of a senescence-like phenotype in lung cells. These alterations could have mechanistic implications regarding the carcinogenic potential of PM10., (Copyright © 2013 Elsevier Ireland Ltd. All rights reserved.)

Objective: Studies reporting low prevalence of HPV in OSCC with declining age at presentation are increasing. The aim of this study was to determine the prevalence of HPV in a group of OSCC cases and controls in a Mexican population., Methods: The matched case-control study included 80 OSCC cases and 320 controls. HPV/DNA presence was evaluated through PCR amplification using three sets of consensus primers for the L1 gene. A conditional logistic regression analysis was carried out for the matched OSCC cases and controls. Interactions between risk factors and OCSS were tested in the construction process of the models., Results: HPV prevalence was 5% in OSCC cases and 2.5% in controls. HPV-detected types were 16, 18 and 56. According to conditional logistics regression model, an association was detected between HR-HPV and OSCC. All HR-HPV-positive OSCC cases corresponded to young patients (<45 years), non-smokers and non-alcohol drinkers., Conclusions: The HR-HPV can be a contributing factor to oral carcinogenesis, especially in younger individuals without known risk factors such as tobacco and alcohol., (© 2013 John Wiley & Sons A/S. Published by John Wiley & Sons Ltd.)

Background: Many studies have shown gemcitabine and cisplatin are radiosensitizers. Concurrent chemoradiation seems to be an efficient approach for treatment of advanced head and neck cancer (HNC), but toxicity is significant., Objective: To evaluate safety and explore efficacy of alternating chemotherapy with gemcitabine and cisplatin concurrent with radiotherapy in patients with advanced non-metastatic HNC., Patients and Methods: Twenty-eight patients diagnosed with advanced Squamous Cell Carcinomas of the Head and Neck (SCCHN) in stages III (28%), IVa (36%), and IVb (36%) were treated with gemcitabine: 100mg/m(2) alternating with cisplatin: 50mg/m(2) concurrent with radiotherapy at doses of 2 Gy/day until completing 70 Gy. While awaiting for concurrent treatment, eleven patients received induction chemotherapy with cisplatin: 100mg/m(2) and 5-FU: 1000 mg/m(2). Toxicity, especially in relation to mucositis, xerostomy, dysphagia, leucopenia and radiodermitis was evaluated., Results: 5-year progression-free survival was 27.8 ± 17.2% (CI-95: 0-61.5) and overall survival was 55.9 ± 11% (CI: 34.4-77.5). Overall response rate was 93%; complete response was 64.3% and partial response was 28.6%. Extensive surgery for primary site was avoided in 19 patients (70.4%). Grade 3-4 adverse events were mucositis (46.4%), leucopenia (14.2%), dysphagia (25%), xerostomy (10.7%) and radiodermitis (3.6%). Response rates and toxicity were not significantly different among those patients with and without induction chemotherapy, but survival was higher in patients receiving induction., Conclusions: Gemcitabine alternating with cisplatin concurrent with radiotherapy is an active and safe treatment that deserves further study., (Copyright © 2012 Elsevier Ltd. All rights reserved.)

The dissociative electron-attachment (DEA) phenomena at the N1-H and N3-H bonds observed experimentally at low energies (<3 eV) in uracil are studied with the CASSCF/CASPT2 methodology. Two valence-bound π(-) and two dissociative σ(-) states of the uracil anionic species, together with the ground state of the neutral molecule, are proven to contribute to the shapes appearing in the experimental DEA cross sections. Conical intersections (CI) between the π(-) and σ(-) are established as the structures which activate the DEA processes. The N1-H and N3-H DEA mechanisms in uracil are described, and experimental observations are interpreted on the basis of two factors: (1) the relative energy of the (U-H)(-) + H fragments obtained after DEA with respect to the ground-state equilibrium structure (S0) of the neutral molecule (threshold for DEA) and (2) the relative energy of the CIs also with respect to S0 (band maxima). The π1(-) state is found to be mainly responsible for the N1-H bond breaking, whereas the π2(-) state is proved to be involved in the cleavage of the N3-H bond.

DNA methylation is an important regulator of gene transcription, and its role in carcinogenesis has been a topic of considerable interest in the last few years. Of the all epigenetic modifications, methylation, which represses transcription of the promoter region of tumor suppressor genes leading to gene silencing, has been most extensively studied. Oral squamous cell carcinoma (OSCC) has long been known to be the endpoint of many genetic changes, not only genomic mutations but also abnormal epigenetic modifications, as such, promoter methylation, contribute to development of this tumors. Recent studies have shown that promoter methylation of tumor suppressor genes is an important factor in carcinogenesis of OSCC. Some of the main genes that frequently showed promoter methylation in OSCC are those that participate in diverse processes such as regulation of the cell cycle, DNA repair, proliferation, and apoptosis. The aim of this review is to assess the current state of knowledge regarding promoter methylation of diverse genes in OSCC., (© 2011 John Wiley & Sons A/S.)

Lipopolysaccharide induces TLR-1-8 mRNAs over-expression in corneal fibroblast. Analyzing if other TLR-ligands can do the same, we found that peptidoglycan does, but not muramyldipeptide, lipoteichoic acid and polyI:C. This suggests that the recognition of lipopolysaccharide and peptidoglycan is enough to alert these cells against microorganisms through the over-expression of the majority TLRs.

Promoter methylation is believed to inactivate the expression of hMLH1. This process has been implicated in the tumorigenesis of oral squamous cell carcinoma (OSCC). Thus, the aim of this study was to determine the profile of hMLH1 methylation and protein expression in OSCC. The matched case-control study included 50 OSCC cases and 200 controls, with a median of age 64 (Q₁-Q₃ 54-71) years. Protein expression was determined by immunohistochemical staining, and hMLH1 gene promoter methylation was analyzed by methylation-specific polymerase chain reaction (MSP). A conditional logistic regression model for risk factors was built for OSCC cases and matched controls. Promoter methylation of hMLH1 was detected in 38 (76%) OSCC cases, but in none of the control samples. Of the 38 OSCC samples with promoter methylation, 12 (32%) were negative for hMLH1 protein, and corresponded to early clinical stages (10 in stage II and 2 in stage I). All 12 unmethylated samples showed positive stain for hMLH1. Multiple logistic regression analysis showed an OR of 16.54 (IC 95%: 1.69-161.68, p=0.016) for methylation of the hMLH1 gene and early stages of OSCC, adjusting by gender and tobacco use. This study showed a high frequency of hMLH1 promoter methylation that occurred in most of the early stage cases and in about half of the late stage cases. It is proposed that hMLH1 promoter methylation is an early event that is maintained during tumor progression., (Copyright © 2010 Elsevier Ltd. All rights reserved.)

The present study provides new insight into the intrinsic mechanisms for the population of the triplet manifold in DNA nucleobases by determining, at the multiconfigurational CASSCF/CASPT2 level, the singlet-triplet states crossing regions and the main decay paths for their lowest singlet and triplet states after near-UV irradiation. The studied singlet-triplet interacting regions are accessible along the minimum energy path of the initially populated singlet bright (1)ππ* state. In particular, all five natural DNA/RNA nucleobases have, at the end of the main minimum energy path and near a conical intersection of the ground and (1)ππ* states, a low-energy, easily accessible, singlet-triplet crossing region directly connecting the lowest singlet and triplet ππ* excited states. Adenine, thymine, and uracil display additional higher-energy crossing regions related to the presence of low-lying singlet and a triplet nπ* state. These funnels are absent in guanine and cytosine, which have the bright (1)ππ* state lower in energy and less accessible nπ* states. Knowledge of the location and accessibility of these regions, in which the singlet-triplet interaction is related to large spin-orbit coupling elements, may help to understand experimental evidence such as the wavelength dependence measured for the triplet formation quantum yield in nucleobases and the prevalence of adenine and thymine components in the phosphorescence spectra of DNA.

Purpose: Knowledge of oral mucositis (OM) in patients with acute leukemia (AL) and chemotherapy (CT) has remained limited. Thus, a prospective, longitudinal study was undertaken to characterize clinical features, associated risk factors, and behavior of OM in a cohort of AL patients starting CT., Methods: Prospective and longitudinal study. A cohort of patients, older than 15 years of age with AL, scheduled to receive CT, was followed from March 2006 to October 2007. At baseline and three times per week, for 21 days, patients had an oral examination performed using the Oral Mucositis Assessment Scale (OMAS); also, oral pain and difficulty to swallow were recorded using a visual analog scale. Weekly, salivary flow measurements (Schirmer's test modified version) were done., Results: A cohort of 29 AL patients was followed for a median time of 21 (range, 14-53) days; 12 (41.4%) developed OM, with a mean OMAS score of 0.181 (SD +/- 0.56) and a mean peak OMAS score of 1.8 (SD +/- 0.56). The OM onset mean time was 9.8 (range, 2-20, SD +/- 6.09) days, with a mean duration of 7 (range, 3-14, SD +/- 4.15) days. OM was significantly correlated with salivary flow [rs = 0.420 (P = 0.0051)], oral pain [rs = 0.47 (P < 0.0001)], ability to swallow [rs = 0.36 (P = 0.0001)], and type of food intake [rs = 0.38 (P < 0.0001)]., Conclusions: OM is a frequent and early side effect of CT closely correlated with oral pain, difficulty to swallow, and impairment in food intake.

The photophysics of 1-aminonaphthalene (1-napthylamine, AMN) has been investigated on the basis of a constructive experimental-theoretical interplay derived from time-resolved measurements and high-level quantum-chemical ab initio CASPT2//CASSCF calculations. Transient ionization signals at femtosecond resolution were collected for AMN cold isolated molecules following excitation from the vibrationless ground level to a number of vibrational states (within the pump resolution) in the lowest accessible excited state and further multiphoton ionization probing at 500, 800, and 1300 nm. Theory predicts two pipi* states, (1)L(b) and (1)L(a), as the lowest singlet electronic excitations, with adiabatic transitions from S(0) at 3.50 and 3.69 eV, respectively. Since the associated oscillator strength for the lowest transition is exceedingly small, the (1)L(b) state is not expected to become populated significantly and the (1)L(a) state appears as the main protagonist of the AMN photophysics. Though calculations foresee a surface crossing between (1)L(a) and the lower (1)L(b) states, no dynamical signature of it is observed in the time-dependent measurements. In the relaxation of (1)L(a), the radiant emission competes with the intersystem crossing and internal conversion channels. The rates of these mechanisms have been determined at different excitation energies. The internal conversion is mediated by a (1)L(a)/S(0) conical intersection located 0.7 eV above the (1)L(a) minimum. The relaxation of a higher-lying singlet excited state, observed above 40 000 cm(-1) (4.96 eV) and calculated at 5.18 eV, has been also explored.

Oral lesions such as candidosis, hairy leukoplakia (HL) and oral ulcers are strikingly absent in the numerous reports of immune reconstitution inflammatory syndrome (IRIS). To document oral manifestations attributable to immune reconstitution, we conducted a longitudinal follow-up of a cohort of HIV+ individuals starting highly active antiretroviral therapy (HAART) and completing oral pathology follow-up up to 12 weeks after treatment initiation. HIV-infected patients had oral examinations, CD4+ T-cell count and viral load determinations performed at baseline, and at weeks 4, 8 and 12 after HAART initiation. Among individuals with satisfactory viral response and recovery of > or =50 CD4+ T-cell/microL, eight patients complied with strict IRIS criteria: two developed clinical signs of oral candidosis (OC), two oral ulcers, three HL and one Kaposi's sarcoma. CD4+ T-cell counts at symptom onset suggested no remaining immune suppression. Our findings show that cases of OC, HL and recurrent ulcers can be instances of IRIS.

Background: The origin of spindle cells (SC) in oral Kaposi's sarcoma (OKS) is still an intriguing aspect. Thus the aim of the present study was to compare the clinical, histological and immunohistochemical characteristics of OKS and oral pyogenic granuloma (OPG), in order to contribute to the knowledge of the cells involved in Kaposi's sarcoma pathogenesis., Methods: In this retrospective, observational and comparative study, 39 OKS and 30 OPG cases were included. Immunohistochemical studies were performed for vimentin, alpha SMA, desmin, C-kit, CD34, D2-40 and LANA-1 [human herpesvirus-8(HHV-8)]. Statistical comparisons were done using the chi-square and Wilcoxon-Mann-Whitney rank sum tests., Results: Fourteen (35.9%) OKS cases also affected the skin, and 83.8% involved the palate. All OKS and OPG were positive for vimentin and CD34. OKS samples were positive for alpha SMA, and 25.6% expressed C-kit. All OKS cases were positive for HHV-8, and the number of positive cells increased significantly from early / intermediate to late histological stage. D2-40 was expressed in the cellular component and vascular walls of all OKS cases, but it was negative in OPG. HHV-8 expression was increased in late histological stages of OKS lesions., Conclusions: The expression of D2-40 marker in the vascular walls and SC supports the view of a lymphatic differentiation in neoplastic cells of OKS. Desmin, alpha SMA, D2-40, C-kit and HHV-8 were the main markers differently expressed in OKS and OPG.

The higher formation yields measured in the ultrafast photoinduced formation of cyclobutane thymine dimers (T<>T) with respect to those of cytosine (C<>C) are explained, on the basis of ab initio CASPT2 results, by the existence in thymine of more reactive orientations and a less efficient photoreversibility, whereas in cytosine the funnel toward the photolesion becomes competitive with that mediating the internal conversion of the excited-cytosine monomer.

Based on CASPT2 results, the present contribution establishes for the first time that cytosine photodimer formation (C< >C) is mediated along the triplet and singlet manifold by a singlet-triplet crossing, (T1/S0)X, and by a conical intersection, (S1/S0)CI, respectively. The former can be accessed in a barrierless way from a great variety of photochemical avenues and exhibits a covalent single bond between the ethene C6-C6' carbon atoms of each monomer. The efficiency of the stepwise triplet mechanism, however, would be modulated by the effectiveness of the intersystem crossing mechanism. The results provide the grounds for the understanding of the potential photogenotoxicity of endogenous and exogenous compounds via triplet-triplet sensitization, with a lower bound for cytosine oligonucleotides predicted to be 2.70 eV, and give support to the traditional view of the primary role of triplet excited states in the photochemistry of DNA, a well-known source of photoproducts in solution under triplet photosensitization conditions. The function played by singlet excimers (excited dimers) to explain both the red-shifted fluorescence and photoreaction is highlighted. A rationale on the pronounced wavelength dependence of the observed fluorescence is offered. Geometrical arrangements at the time of light irradiation close to, but energetically above, (S1/S0)CI are suggested as reactive orientations that become prone to produce C< >C directly, with no energy barrier. Because of the outstanding intrinsic ability of cytosine to form stable relaxed excimers, the system located near the bound relaxed excimer has to accumulate enough vibrational energy to surmount a small barrier of 0.2 eV to reach (S1/S0)CI, making the overall process to proceed at a slower relative rate as compared to other compounds such as thymine, which is not susceptible of forming so stable excimers.

Background: The aim of the present study was to compare the prevalence of HIV-related oral lesions (HIV-OL) between two health centers for HIV in Mexico City and to analyze the factors that, in addition to combined antiretroviral therapy (CART) and low CD4(+), may be associated with possible differences in prevalence., Methods: A cross-sectional observational study was performed between January 2000 and February 2003 at the Instituto Nacional de Ciencias Médicas y Nutrición Salvador Zubirán (INCMNSZ), a specialized referral center for HIV/AIDS patients and the Clínica Especializada Condesa (CEC), a primary care center for HIV-infected individuals without social security insurance. A consecutive sample of HIV-infected individuals had an oral examination based on established clinical criteria. Demographic, clinical and laboratory data were obtained. Independent association of each factor with specific HIV-OL was assessed by logistic regression modeling., Results: Eight hundred fifty individuals were examined (INCMNSZ: 479; CEC: 371). Hairy leukoplakia (HL), periodontal disease (PD) and Kaposi's sarcoma (KS) were independently associated with the study site [odds ratio (OR) = 1.7 (95% confidence interval (CI): 1.1-2.4), OR = 4.2 (95% CI: 1.3-13), OR = 10.1 (95% CI: 2.7-38.2), respectively], being more frequent in CEC patients. HL was independently associated with men having sex with men OR = 1.7 (95% CI: 1.1-2.8). All HIV-OL were independently associated with CD4(+) counts and, with the exception of PD and KS, with time under CART., Conclusions: The present comparative study showed that several factors were associated with a difference in prevalence of oral lesions found in two AIDS clinics located in Mexico City. Severe immune suppression, CART duration and the study site were associated with HIV-OL. Further investigation into factors such as socioeconomic determinants associated with HIV-OL is warranted.

The report describes an HIV/AIDS patient seen at a referral center in Mexico City, in whom a mycobacterial infection in the oral mucosa, probably tuberculosis (TB) was identified. The purpose is to describe the clinical and histological findings in an HIV-infected patient, who after being treated successfully for tuberculous lymphangitis 4 years ago, presented with a lingual ulcer as the only suggestive sign of recurrence of mycobacterial infection, probably M. tuberculosis. A 39-year-old man seen in the HIV clinic of the Instituto Nacional de Ciencias Médicas y Nutrición "Salvador Zubirán" in Mexico City since 1991 for HIV infection. In 1999 the patient developed tuberculous lymphangitis; he was managed with a 4-drug regimen for 12 months, with improvement of local and systemic symptoms. In May of 2003, the patient presented a painful superficial lingual ulcer, 0.7 cm in diameter, well circumscribed, crateriform with slightly elevated, irregular and indurated borders, of 4 months duration. The histopathological examination showed chronic granulomatous inflammation with giant multinucleated cells, suggestive of mycobacterial infection, and recurrence of TB was considered. Rifampin, isoniazide, pyrazinamide, ethambutol and streptomycin were administered. The lingual lesion improved with partial healing at the first week and total remission at 45 days after the beginning of the antituberculous treatment. In June, 2003, the patient began highly active antiretroviral therapy (HAART) that included two NRTIs and one NNRTI. At 7 months of follow-up, the patient remains free of lingual lesions. The particularity of the present case is that the lingual ulcer was the only sign of infection by mycobacteria, suggestive of TB, in an HIV/AIDS patient that probably represented a recurrence of a previous episode.

In developing countries, the variations in the clinical spectrum of human immunodeficiency virus (HIV)-related oral lesions over time, and the possible effects of antiretroviral therapy, have not been described. In this study we evaluate the clinical spectrum of oral lesions in a series of HIV-infected patients when first examined at the acquired immunodeficiency syndrome (AIDS) clinic of a tertiary care institution in Mexico City, Mexico, and the changes observed over 12 years. All HIV-infected adult patients had an oral examination performed by specialists in oral pathology and medicine who used established clinical diagnostic criteria for oral lesions. Four periods were defined according to the evolving pattern of antiretroviral use: the first 2 were before the introduction of highly active antiretroviral therapy (HAART) and the last 2 were during more established use of HAART. For the statistical analysis the chi-square test for contingency tables and the chi-square test for trend were utilized. For dimensional variables, except age, the Kruskal-Wallis or Mann-Whitney rank sum tests were used when applicable and trend was tested with the Spearman correlation coefficient. Age was tested through analysis of variance (ANOVA) and linear regression analysis. Alpha value was set at p = 0.05 for each test. In the 12-year study, 1,000 HIV-infected patients were included (87.9% male). At the baseline examination, oral lesions strongly associated with HIV were present in 47.1% of HIV-infected patients. Oral candidosis (31.6%), hairy leukoplakia (22.6%), erythematous candidosis (21.0%), and pseudomembranous candidosis (15.8%) were the most frequent lesions. Oral Kaposi sarcoma (2.3%), HIV-associated periodontal disease (1.7%), and oral non-Hodgkin lymphoma (0.1%) were less frequent. HIV-related oral lesions decreased systematically-by half during the course of the 4 study periods (p < 0.001). Except for Kaposi sarcoma, all oral lesions strongly associated with HIV showed a trend to decrease significantly during the study period. No apparent variation in the occurrence of salivary gland disease or human papillomavirus-associated oral lesions was found. A significant trend to a lower prevalence was observed in the group of patients who were already taking antiretroviral therapy, non-HAART and HAART (p < 0.001 and p = 0.004, respectively). Only a discrete reduction, barely significant, was noted among untreated patients (p = 0.060). By Period IV (1999-2001), those who received HAART showed the lowest prevalence of oral lesions strongly associated with HIV (p < 0.001). Patients with oral lesions strongly associated with HIV had significantly lower median CD4+ counts and higher viral loads than those without oral lesions strongly associated with HIV (p < 0.001 and p = 0.005, respectively). When CD4+ counts were correlated with prevalence of oral candidosis, a consistently negative association was found; this association prevailed even after the study group was partitioned according to period. In this selected cohort of 1,000 patients with HIV infection, the clinical spectrum of HIV-related oral lesions has changed over the 12-year study, with a decreased prevalence of most oral lesions. Our findings probably represent improvements in medical care of HIV-infected persons, earlier detection of HIV-infected patients at the AIDS clinic, the increasing use of prophylactic drugs to prevent secondary AIDS-related opportunistic infections, and, perhaps most important, the availability of potent antiretroviral therapy in recent years, since the introduction of HAART.

Objective: To estimate the prevalence of oral lesions and its association with HIV serological status., Material and Methods: A cross-sectional descriptive study was conducted between 1998 and 1999 in Mexico City, among 512 subjects attending two information centers of Centro Nacional para la Prevención del VIH/SIDA e ITS (CONASIDA, National Center for Prevention of HIV/AIDS and Sexually Transmitted Infections) for HIV serologic testing. The oral examination was performed without knowledge of the HIV status. Statistical analysis was conducted using Student's t test, Fisher's exact test and the chi 2 test; odds ratios and 95% CI were also calculated., Results: A total of 512 individuals were examined, 68 of whom were HIV-positive. HIV-related oral lesions (OL), were evident in 65% (44/68) of the HIV-positive individuals; 95% of them consisted in oral candidosis (OC) and hairy leukoplakia (HL). OC and HL were strongly associated with seropositivity to HIV., Conclusions: OC and HL were the oral lesions most strongly associated to HIV seropositivity. The English version of this paper is available at: http://www.insp.mx/salud/index.html.