NtWBC1, an ABC transporter gene specifically expressed in tobacco reproductive organs

To identify genes specifically or predominantly expressed in the stigmas/styles and to establish their possible function in the reproductive process of plants, a tobacco stigma/style cDNA library was constructed and differentially screened, resulting in the isolation of several cDNA clones. The molecular characterization of one of these clones is described here. After sequencing the cDNA and the isolated genomic clone, it was determined that the corresponding gene encodes a protein containing an ATP-binding cassette, characteristic of ABC transporters. This gene, designated as NtWBC1 (Nicotiana tabacum ABC transporter of the White-Brown Complex subfamily), encodes a protein that contains the typical structure of the 'half-transporters' of the White subfamily. To establish the spatial expression pattern of the NtWBC1 gene, northern blot and real-time RT-PCR analyses with total RNA from roots, stems, leaves, sepals, petals, stamens, stigmas/styles, ovaries, and seeds were performed. The result revealed a transcript of 2.5 kb present at high levels in stigmas and styles and a smaller transcript (2.3 kb) present at a lower level in stamens. NtWBC1 expression is developmentally regulated in stigmas/styles, with mRNA accumulation increasing toward anthesis. In situ hybridization experiments demonstrated that NtWBC1 is expressed in the stigmatic secretory zone and in anthers, at the stomium region and at the vascular bundle. NtWBC1 is the first ABC transporter gene with specific expression in plant reproductive organs to be identified and its expression pattern suggests important role(s) in the reproductive process.

Genetic diversity of Rhizoctonia solani AG-3 from potato and tobacco in North Carolina

Anastomosis group 3 (AG-3) of Rhizoctonia solani (teleomorph = Thanatephorus cucumeris) is frequently associated with diseases of potato (AG-3 PT) and tobacco (AG-3 TB). Although isolates of R. solani AG-3 from these two Solanaceous hosts are somatically related based on anastomosis reaction and taxonomically related based on fatty acid, isozyme and DNA characters, considerable differences are evident in their biology, ecology, and epidemiology. However, genetic diversity among field populations of R. solani AG-3 PT and TB has not been documented. In this study, the genetic diversity of field populations of R. solani AG-3 PT and AG-3 TB in North Carolina was examined using somatic compatibility and amplified fragment length polymorphism (AFLP) criteria. A sample of 32 isolates from potato and 36 isolates from tobacco were paired in all possible combinations on PDA plus activated charcoal and examined for their resulting somatic interactions. Twenty-eight and eight distinct somatic compatibility groups (SCG) were identified in the AG-3 PT and AG-3 TB samples, respectively. AFLP analyses indicated that each of the 32 AG-3 PT isolates had a distinct AFLP phenotype, whereas 28 AFLP phenotypes were found among the 36 isolates of AG-3 TB. None of the AG-3 PT isolates were somatically compatible or shared a common AFLP phenotype with any AG-3 TB isolate. Clones (i.e., cases where two or more isolates were somatically compatible and shared the same AFLP phenotype) were identified only in the AG-3 TB population. Four clones from tobacco represented 22% of the total population. All eight SCG from tobacco were associated with more than one AFLP phenotype. Compatible somatic interactions between AG-3 PT isolates occurred only between certain isolates from the same field (two isolates in each of four different fields), and when this occurred AFLP phenotypes were similar but not identical.

A tobacco cDNA reveals two different transcription patterns in vegetative and reproductive organs

In order to identify genes expressed in the pistil that may have a role in the reproduction process, we have established an expressed sequence tags project to randomly sequence clones from a Nicotiana tabacum stigma/style cDNA library. A cDNA clone (MTL-8) showing high sequence similarity to genes encoding glycine-rich RNA-binding proteins was chosen for further characterization. Based on the extensive identity of MTL-8 to the RGP-1a sequence of N. sylvestris, a primer was defined to extend the 5′ sequence of MTL-8 by RT-PCR from stigma/style RNAs. The amplification product was sequenced and it was confirmed that MTL-8 corresponds to an mRNA encoding a glycine-rich RNA-binding protein. Two transcripts of different sizes and expression patterns were identified when the MTL-8 cDNA insert was used as a probe in RNA blots. The largest is 1,100 nucleotides (nt) long and markedly predominant in ovaries. The smaller transcript, with 600 nt, is ubiquitous to the vegetative and reproductive organs analyzed (roots, stems, leaves, sepals, petals, stamens, stigmas/styles and ovaries). Plants submitted to stress (wounding, virus infection and ethylene treatment) presented an increased level of the 600-nt transcript in leaves, especially after tobacco necrosis virus infection. In contrast, the level of the 1,100-nt transcript seems to be unaffected by the stress conditions tested. Results of Southern blot experiments have suggested that MTL-8 is present in one or two copies in the tobacco genome. Our results suggest that the shorter transcript is related to stress while the larger one is a flower predominant and nonstress-inducible messenger.

β-carotene attenuates the paradoxical effect of tobacco smoke on the mortality of rats after experimental myocardial infarction

The objective of this study was to investigate the effects of exposure to tobacco smoke (ETS) in rats that were or were not supplemented with dietary β-carotene (BC), on ventricular remodeling and survival after myocardial infarction (Ml). Rats (n = 189) were allocated to 4 groups: the control group, n = 45; group BC administered 500 mg/kg diet, n = 49, BC supplemented rats; group ETS, n - 55, rats exposed to tobacco smoke; and group BC+ETS, n = 40. Wistar rats weighing 10O g were administered one of the treatments until they weighed 200 to 250 g (∼5 wk). The ETS rats were exposed to cigarette smoke for 30 min 4 times/d, in a chamber connected to a smoking device. After reaching a weight of 200-250 g, rats were subjected to experimental MI (coronary artery occlusion) and mortality rates were determined over the next 105 d. In addition, echocardiographic, isolated heart, morphometrical, and biochemical studies were performed. Mortality data were tested using Kaplan-Meyer curves and other data by 2-way ANOVA. Survival rates were greater in the ETS group (58.2%) than in the control (33.3%) (P = 0.001) and BC+ETS rats (30.0%) (P = 0.007). The groups did not differ in the other comparisons. Left ventricular end-diastolic diameter normalized to body weight was greater and maximal systolic pressures were lower in the ETS groups than in non-ETS groups. Previous exposure to tobacco smoke induced a process of cardiac remodeling after MI. There is a paradoxical protector effect with tobacco smoke exposure, characterized by lower mortality, which is offset by BC supplementation. © 2005 American Society for Nutritional Sciences.

Evaluation of clinical periodontal conditions in smokers and non-smokers

Given that tobacco smoking habit is a risk factor for periodontal diseases, the aim of this study was to compare clinical periodontal aspects between smokers and non-smokers. The clinical status were assessed in 55 patients, 29 smokers and 26 non-smokers, aged 30 to 50 years, with mean age of 40. The clinical parameters used were: probing depth (PD), plaque index (PI), gingival index (GI), clinical attachment level (CAL), gingival recession (GR) and gingival bleeding index (GBI) for arches (upper and lower ) and teeth (anterior and posterior). Tooth loss was also evaluated in both groups. Multiple regression analysis showed: tendency of greater probing depth and clinical attachment level means for smokers; greater amount of plaque in smokers in all regions; greater gingival index means for non-smokers with clinical significance (p<0.05) in all regions. Although, without statistical significance, the analysis showed greater gingival bleeding index means almost always for nonsmokers; similar gingival recession means in both groups and tendency of upper tooth loss in smokers and lower tooth loss in non-smokers. The findings of this study showed that clinical periodontal parameters may be different in smokers when compared to non-smokers and that masking of some periodontal signs can be a result of nicotine's vasoconstrictor effect.

Oral lichen planus: A retrospective study of 110 Brazilian patients

Background. Oral lichen planus (OLP) is a chronic autoimmune disease characterized by multiple clinical presentations and a relatively high prevalence in the population. This retrospective patient record study investigated the profile of OLP in a group of Brazilian patients seen between 1989 and 2009. Findings. The clinical records were analyzed and data such as gender, age, race, clinical presentation of OLP, site affected, presence of symptoms and extraoral manifestations of the disease, smoking habit, and consumption of alcoholic beverages were obtained. Among the 1822 records of patients with oral mucosal lesions, OLP was identified in 6.03%. Of these, 76.36% were females, with a mean age of 54 years, and 85% were whites. The reticular form was the most frequent (81.81%). Extraoral lesions were observed in 32.72% of the patients and painful symptoms were reported by 50.90%. The cheek mucosa was the site most affected (92.72%) and multiple oral lesions were observed in 77.27% of the patients. Among patients with OLP, 18.18% reported a smoking habit and 29.09% the consumption of alcoholic beverages. Conclusions. This retrospective study showed a relatively high prevalence of OLP in the population studied, with a predominance of the disease among middle-aged white women and bilateral involvement of the cheek mucosa. Reticular lesions were the most frequent, followed by the erosive form which is mainly associated with painful symptoms. No relationship with tobacco or alcohol consumption was observed. © 2010 Almeida et al; licensee BioMed Central Ltd.

Influence of lisinopril on cardiac remodeling induced by tobacco smoke exposure

Background: To investigate the effect of lisinopril on cardiac remodeling induced by smoking. Material/Methods: Rats were allocated into 3 groups: group CON (n=8): control; group CSE (n=8): cigarette smoke exposure; group CSE-LIS (n=8): exposed to tobacco smoke and treated with lisinopril. Results: After 2 months, the tail systolic pressure was lower in CSE-LIS (CON=116 ±27 mm Hg, CSE=126±16, CSE-LIS=89±12; P<.001). CSE animals showed higher left ventricular systolic diameter (CON=8.25±2.16 mm/kg, CSE=11.5±1.3, CSE-LIS=9.27±2.00; P=.009) and myocyte cross-sectional area (CON=245±8 μm2, CSE=260±17, CSE-LIS=238±12; P=.01) than CON and CSE-LIS. The ejection fraction (CON =0.91±0.02, CSE=0.86±0.02, CSE-LIS=0.92±0.03; P=.002) and fractional shortening (CON=55.7±4.41%, CSE=48.7±3.43, CSE-LI=58.2±7.63; P=.006) were lower in CSE group than CON and CSE-LIS. CSE and CSE-LIS animals showed higher collagen amounts (CON=3.49±0.95%, CSE= 5.01±1.58, CSE-LIS=5.27±0.62; P=.009) than CON. CON group showed a higher connexin 43 amount in the intercalated disc (CON=3.70±0.38, CSE=2.13±0.53; CSE-LIS=2.17±0.73; P=.004) than CSE and CSE-LIS. There were no differences in IFN-g or TNF-a cardiac levels among the groups. Conclusions: Lisinopril attenuated both morphologic and functional abnormalities induced by exposure to tobacco smoke. In addition, this effect was associated with diminished blood pressure, but not alterations in connexin 43 distribution, cytokine production or collagen amount. © Med Sci Monit, 2010.

Influência da taurina na remodelação cardíaca induzida pela exposição à fumaça do cigarro

Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES)

Influência do interior do inibidor da enzina conversora da angiotensina na remodelação cardíaca induzida pela exposição á fumaça do cigarro

Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES)

Overexpression of UCP1 in tobacco induces mitochondrial biogenesis and amplifies a broad stress response

Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)

Relationship Between Jaw Apparatus, Feeding Habit, and Food Source in Oriental Woodpeckers

Associations among feeding habit, beak type, and food source in birds have been widely studied and are well known to exist. The relationship between feeding habit and jaw apparatus in birds has not attracted attention from ornithologists, perhaps because of the complexity of the skeletal morphology of the feeding system of birds. The goal of this study was to compare the jaw apparatus and foraging strategies of various Oriental species of the Picidae (Meiglyptini and Picini tribes) using a morphofunctional analysis of the skeletal structure of the jaw apparatus. This study showed that there are at least three types of jaw apparatus in these woodpeckers, as follows: 1) robust, developed, and complex; 2) complexity and development intermediate, as observed in Meiglyptes tristis and Dinopium spp., whose main foraging method involves gleaning, probing, and tapping; and 3) poorly developed, as observed in Picus miniaceus and Hemicircus concretus. The success of woodpeckers as a natural group is due not only to their feeding diversity, but also their ability to explore a wide range of different resources, as appropriate to their jaw apparatus.

Ocorrência de tabagismo e dependência nicotínica em universitários

In Brazil, smoking incidence varies between 9.5% and 21.2% and it is more common among men. In college students incidence can reach 14% depending on the region, which is quite disturbing. Joining college is a crucial period for the commencement or maintenance of smoking. The Knowledge among college students about tobacco use is critical to devise strategies for intervention in this population. The objectives were to establish the occurrence of smoking and risk factors, nicotine dependence in college students and college goers. We interviewed students, teachers and administrative personnel from the Philosophy and Science School at UNESP at Marilia, from both sexes, regardless their age, which visited the First Week Against Tobacco event. The sociodemographic data, smoking status, time as a smoker, cigarettes smoked, date when they started smoking, history of smoking in the family, friends or associates were questioned. We also assessed the degree of motivation to quit smoking and the degree of nicotine dependence. Data were presented using descriptive statistics. Comparisons between categorical variables were made using the chi-square test (p <0.05). A total of 432 people, 180 men and 252 women, average aged 22.6 ± 6.9 years were researched. From the volunteers studied, 267 (61.8) had tried cigarettes and 171 of them (64%) reported that they were offered by friends. As a whole, 79 (18.3%) of these people were smokers, 52 (65.8%) reported intending to quit smoking and in 37 of them (46.8%), the degree of nicotine dependence was very low. Of all the smokers, 63 had smokers in the family and all of them had friends who smoked. 28.9% of all men were smokers and 10.7%of all women. The occurrence of smoking was 18.3% and the risk factor associated to smoking habit is related to friendship and family, and very low nicotine dependence.