The effects of habitat complexity and hydraulic conditions on the establishment of benthic stream macroalgae

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Behaviour of interleukin-2 serum levels in advanced non-small-cell lung cancer patients: relationship with response to therapy and survival

 Interleukin(IL)-2 is a T helper (Th) 1 type cytokine that has been shown to play an important role in antitumour immune responses. In this study, the prognostic significance of serum IL-2 levels was investigated in 60 advanced non-small-cell lung cancer (NSCLC) patients. IL-2 serum levels were determined before chemotherapy, at the end of chemotherapy and during follow-up, using a commercially available enzyme-linked immunoadsorbent assay kit. The results were analysed according to the response to therapy and were used to generate a model predicting overall survival and time to treatment failure. All 60 patients were shown to have higher IL-2 serum levels than controls (P < 0.0001). Stage IV patients had significantly lower IL-2 levels than stage III patients (P < 0.0001), although they were still significantly higher than controls (P < 0.0001). It is interesting that, when patients were divided into responders and non-responders according to the response to therapy, the former were shown to have significantly higher pre-chemotherapy levels than the latter (P < 0.0001). Moreover, a further significant increase in IL-2 serum levels (P=0.004) and a significant decrease (P < 0.0001) were shown in responders and non-responders, respectively at the end of the therapy. Using univariate and multivariate analyses, both overall survival and time to treatment failure were shown to be affected by the mean pathological levels of IL-2. Furthermore, the prognostic significance of the serum level of IL-2 was confirmed by the stepwise regression analysis. In conclusion, determination of pre-treatment IL-2 serum levels was shown to be of independent prognostic utility in patients with advanced NSCLC; therefore, its possible use for prediction of outcome is proposed. Received: 16 March 2000 / Accepted: 27 July 2000     

Dynamics of Vaginal Bacterial Communities in Women Developing Bacterial Vaginosis, Candidiasis, or No Infection, Analyzed by PCR-Denaturing Gradient Gel Electrophoresis and Real-Time PCR

The microbial flora of the vagina plays a major role in preventing genital infections, including bacterial vaginosis (BV) and candidiasis (CA). An integrated approach based on PCR-denaturing gradient gel electrophoresis (PCR-DGGE) and real-time PCR was used to study the structure and dynamics of bacterial communities in vaginal fluids of healthy women and patients developing BV and CA. Universal eubacterial primers and Lactobacillus genus-specific primers, both targeted at 16S rRNA genes, were used in DGGE and real-time PCR analysis, respectively. The DGGE profiles revealed that the vaginal flora was dominated by Lactobacillus species under healthy conditions, whereas several potentially pathogenic bacteria were present in the flora of women with BV. Lactobacilli were the predominant bacterial population in the vagina for patients affected by CA, but changes in the composition of Lactobacillus species were observed. Real-time PCR analysis allowed the quantitative estimation of variations in lactobacilli associated with BV and CA diseases. A statistically significant decrease in the relative abundance of lactobacilli was found in vaginal fluids of patients with BV compared to the relative abundance of lactobacilli in the vaginal fluids of healthy women and patients with CA.     

Trichoderma asperelloides antagonism to nine Sclerotinia sclerotiorum strains and biological control of white mold disease in soybean plants

Sclerotinia sclerotiorum is an important plant pathogen with worldwide distribution that causes severe economic losses of various agricultural crops such as soybean. This fungus is normally controlled with synthetic chemical fungicides that pose risks to the environment, and can be harmful to human health, and they can also induce resistance in pests. The aim of this study was to investigate the potential of Trichoderma asperelloides as a biocontrol agent towards white mold disease on soybeans crops. The antagonism of two strains of T. asperelloides (T25 and T42) isolated from soil samples was determined in-vitro by dual-culture confrontation testing on nine S. sclerotiorum strains obtained from sclerotia collected on diseased soybean plants. The mycelial growth and inhibition of carpogenic and ascospore germination by T. asperelloides extracts, as well as the efficacy of these on white mold control in soybeans were evaluated. Both strains of T. asperelloides exhibited high potential of antagonism. Methanolic and ethyl acetate extracts of the two T. asperelloides strains showed excellent growth inhibition (60–100%) on all of the pathogens tested. The ethyl acetate extracts of both T. asperelloides strains exhibited the highest efficacy against carpogenic germination, decreasing by 20–30% the number of ascospores per apothecium. Strains of T. asperelloides tested were more efficient in controlling white mold than two commercial products made from Trichoderma harzianum. The new strains of T. asperelloides have potential for successful biological control of white mold disease of soybean crops in the field.     

Phenology of a dioecious population of Batrachospermum delicatulum (Batrachospermales, Rhodophyta) in a stream from southeastern Brazil

The seasonal dynamics of a dioecious population of Batrachospermum delicatulum (Skuja) Necchi and Entwisle was evaluated biweekly during the growth period of the macroscopic gametophyte, from late autumn (May) to early spring (October) in a third-order stream from the northeast region of Sao Paulo State, southeastern Brazil (20?43'S, 49?13'W). The population fluctuated throughout the study period in terms of percentage cover, frequency and chlorophyll content. Percent cover and frequency showed a clear pattern with the lowest values at the initial and final stages of the growth period and the highest in July-August (winter). Gametophyte growth was associated with high illumination and low temperature, which agrees with most observations on Batrachospermales in stream environments. Relatively wide variations in reproductive characteristics were observed during the growth period, which were not correlated with percentage cover, frequency and chlorophyll content. The phenologic pattern observed in this population was characterized by a synchronic development of female/male plant ratio with the number of spermatangia per plant resulting in: (i) a higher proportion of fertilized (carpo-sporophytic) plants associated with more male plants; (ii) higher fertilization rates during the periods with higher production of spermatangia per plant; and (iii) higher production of spermatangia per plant when the population had more male plants. These characteristics were largely associated with water temperature and ion content. In terms of reproductive success, the population studied can be regarded as highly efficient, considering the relatively low proportion of male to female plants and high fertilization rates. These data are consistent with a hypothesis to explain high fertilization rates in dioecious species in lotic habitats consisting of outcrossing among adjacent plants with intermingled male and female branches within an algal cluster. Efficient reproductive strategies have been reported in dioecious, monoecious and even mixed populations of B. delicatulum and can be interpreted as adaptations to successfully colonize streams with different characteristics.     

Twelve new polymorphic microsatellite markers from the loggerhead sea turtle (Caretta caretta) and cross-species amplification on other marine turtle species

We describe 12 new polymorphic dinucleotide microsatellite loci and multiplex Polymerase Chain Reaction conditions from the loggerhead sea turtle Caretta caretta. Levels of polymorphism were assessed in 50 individuals from the nesting population of the Cape Verde Islands. Number of alleles ranged from 3 to 13 (average of 7.33) and the values of observed heterozygosities from 0.32 to 0.80 (average of 0.61). Cross-species amplification on three other marine turtles, Chelonia mydas, Eretmochelys imbricata and Dermochelys coriacea, revealed polymorphism and variability at eight, eleven and three loci, respectively.     

Rat carotid artery dilation by PTCA balloon catheter induces neointima formation in presence of IEL rupture

The best animal angioplasty model is the porcine model, which is expensive and not available in all laboratories. The aim of this study was to describe a new rat model of angioplasty. An injury was induced with the use of a standard percutaneous transluminal coronary angioplasty (PTCA) 1.5-mm balloon catheter. The neointimal tissue, arterial dimensions, and the injury index were assessed following angioplasty. Ki-67 expression was detected to evaluate cell turnover after balloon angioplasty. In contrast with the standard Clowes model, a significant neointimal formation was detected only in the presence of ruptured internal elastic lamina (IEL). A positive correlation between the percentage of ruptured IEL and the amount of neointimal tissue was also demonstrated. The percentage of IEL fracture correlates with the proliferation index by anti-Ki-67 immunolabeling 7 and 14 days after the angioplasty. Significant arterial negative remodeling was observed following PTCA balloon dilation. In conclusion, our inexpensive animal model of restenosis after angioplasty may have great relevance toward a better understanding of the mechanisms and toward assessment of new therapeutical strategies for this phenomenon.     

Is COPD a Progressive Disease? A Long Term Bode Cohort Observation

BackgroundThe Global Initiative for Obstructive Lung Diseases (GOLD) defines COPD as a disease that is usually progressive. GOLD also provides a spirometric classification of airflow limitation. However, little is known about the long-term changes of patients in different GOLD grades.ObjectiveExplore the proportion and characteristics of COPD patients that change their spirometric GOLD grade over long-term follow-up.MethodsPatients alive for at least 8 years since recruitment and those who died with at least 4 years of repeated spirometric measurements were selected from the BODE cohort database. We purposely included the group of non survivors to avoid a “survival selection” bias. The proportion of patients that had a change (improvement or worsening) in their spirometric GOLD grading was calculated and their characteristics compared with those that remained in the same grade.ResultsA total of 318 patients were included in the survivor and 217 in the non-survivor groups. Nine percent of survivors and 11% of non survivors had an improvement of at least one GOLD grade. Seventy one percent of survivors and non-survivors remained in the same GOLD grade. Those that improved had a greater degree of airway obstruction at baseline.ConclusionsIn this selected population of COPD patients, a high proportion of patients remained in the same spirometric GOLD grade or improved in a long-term follow-up. These findings suggest that once diagnosed, COPD is usually a non-progressive disease.     

Genetic predictors of response to photodynamictherapy

In Western countries, therapeutic management of patients affected by choroidal neovascularization (CNV) secondary to different typologies of macular degeneration represents a major health care problem. Age-related macular degeneration is the disease most frequently associated with CNV development. Schematically, CNVs can be distinguished into classic and occult subtypes, which are characterized by variable natural history and different responsiveness to some therapeutic procedures. At present, the dramatic vision loss due to CNV can be mainly treated by two interventional strategies, which are utilizable in either single or combined modalities: photodynamic therapy with verteporfin (PDT-V), and intravitreal administration of drugs acting against vascular endothelial growth factor. The combined use of PDT-V and anti-angiogenic drugs represents one of the most promising strategies against neovascular macular degeneration, but it unavoidably results in an expensive increase in health resource utilization. However, the positive data from several studies serve as a basis for reconsidering the role of PDT-V, which has undergone a renaissance prompted by the need for a more rational therapeutic approach toward CNV. New pharmacogenetic knowledge of PDT-V points to exploratory prospects to optimize the clinical application of this intriguing photothrombotic procedure. In fact, a Medline search provides data regarding the role of several single nucleotide polymorphisms (SNPs) as genetic predictors of CNV responsiveness to PDT-V. Specifically, correlations between SNPs and different levels of PDT-V efficacy have been detected by examining the gene variants influencing (i) thrombo-coagulative pathways, i.e. methylenetetrahydrofolate reductase (MTHFR) 677C>T (rs1801133), factor V (F5) 1691G>A (rs6025), prothrombin (F2) 20210G>A (rs1799963), and factor XIII-A (F13A1) 185G>T (rs5985); (ii) complement activation and/or inflammatory processes, i.e. complement factor H (CFH) 1277T>C (rs1061170), high-temperature requirement factor A1 (HTRA1) promoter -512G>A (rs11200638), and two variants of the C-reactive protein (CRP) gene (rs2808635 and rs876538); and (iii) production and bioavailability of vascular endothelial growth factor (VEGFA -2578C>A [rs699947] and rs2146323). This article critically evaluates both the clinical plausibility and the opportunity to utilize the most important SNP-response interactions of PDT-V for an effective upgrade of the current anti-CNV therapeutic scenario. In addition, the pharmacogenetics of a very severe post-PDT-V adverse event, i.e. a decrease in acute vision, is briefly discussed. A comprehensive appraisal of the findings reviewed in this article should be carefully considered to design future trials aimed at verifying (after proper genotypic stratification of the enrolled patients) whether these innovative pharmacogenetic approaches will be able to improve the multifaceted interventional management of neovascular macular degeneration.