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71.
In the absence of DNA damage the LexA protein represses the bacterial SOS system. We performed molecular dynamic simulations of two LexA dimers bound to operators. Our model predicted that rotation of the LexA DNA binding domain, with respect to the dimerised C-terminal domain, is required for selective DNA binding. To confirm the model, double and quadruple cysteine LexA mutants were engineered. Electrophoretic mobility-shift assay and surface plasmon resonance showed that disulfide bond formation between the introduced cysteine residues precluded LexA specific DNA binding due to blocked domain reorientation. Our model could provide the basis for novel drug design.  相似文献   
72.
Recognizing high prevalence of Diabetes mellitus and cardiovascular disorders and low coverage by preventive examinations in the population of returnees, in Osijek Region, we initiated activities for early detection and better managing of chronic diseases. Measures done, were based on public health working methods, such as: education, solidarity and self-responsibility. A special attention was put on psychosocial aspects of the health-related matters. Exactly, free glucose tests were organized with subsequent healthy lifestyles advice session. It was brought to our attention that such intervention should be as much as possible individually oriented, considering many personal and social characteristics of an individual. Gynecological examinations for all women interested in were also organized. On that occasion, women were interviewed in order to get information about their motivation and obstacles for doing preventive examinations and difficulties in adaptation as well. Finally, outcomes of the Project were summarized and put in a larger social context.  相似文献   
73.
The aim of the study was to compare bone properties of two groups of students which strongly differ in the level of their everyday physical activity; the School of Medicine (SM) students and the Faculty of Physical Education (FPE) students, University of Zagreb. Quantitative ultrasound parameters--broadband ultrasound attenuation (BUA) and speed of sound (SOS) were measured. Quantitative ultrasound index (QUI) and estimated bone mineral density (BMD) were calculated by the device software. The final study sample consisted of 165 students from SM (94 males and 71 females) and 215 students from the FPE (164 males, 51 females). Sixty eight percent of FPE students and 21% of SM students reported a high level of everyday physical activity (P < 0.001). All ultrasound parameters were significantly higher in FPE students than in SM students (at the P < 0.001 level). The multiple regression model of the QUI confirmed that the school students attended was the single significant predictor variable for both genders. Our data indirectly showed the beneficial role of physical activity on bone properties.  相似文献   
74.
Immunohistological identification/localization of immunomodulating neuropeptides [vasoactive intestinal polypeptide (VIP) and substance P (SP)] and enzyme nitric oxide synthase (NOS) as well as histomorphometric analyses of kinetics of their release and development of respective nerve fibers density during postnatal ontogenesis of porcine intestinal mucosal immune system (IMIS), were performed in order to assess the role of these molecules involved in maturation of the IMIS. The kinetcs of reactions to VIP, SP and NOS were demonstrated in the samples of jejunum and ileum from conventionally reared pigs. The samples were obtained at 0, 7, 14, 21, 28, 35, 42 and 49 days of age and processed for immunohistological staining. The VIP+ reaction was prevalently visible in the epithelial layer, lamina propria and Lieberkühn crypts (Lc) but also in the submucosa and lamina muscularis along blood and lymphatic vessels. The SP+ fibers were regularly distributed along enteric neurons in the muscular layer. The reaction to NOS was demonstrated in both mucosa and submucosa of ileum and jejunum and in the ileal Peyer''s patches (PP). Intensity of the reaction was more pronounced in the epithelial layer and numerous NOS+ cells were observed around the Lc and inside the follicles of the PP. Also, we have noticed NOS+ blood vessels, particular neurons and nerve fibers in the submucosa and muscular layer of the small intestine. By analyzing quantitative patterns of SP+, VIP+ fibers and release of NOS we have concluded that intensity of their reactions gradually increases with age, except a short period of stagnation after weaning (at age of 28 days), reaching the highest values in the pigs aged between 42 and 49 days. The values obtained by Sperman rank order correlation test (rs) between days of age of pigs and intensity of the reactions in their jejunum/ileum to VIP (rs=0.97/0.95), SP (rs=0.97/0.97) and NOS (rs=0.98/0.95), respectively, showed positive correlations (P<0.05) according to Roemer Orphal scale. Current study showed that post-natal development of porcine IMIS was accompanied by a substantial increase in the secretion of neuropeptides/enzyme tested and that these molecules may participate in the functional maturation of immunoregulatory/bactericidal mechanisms of the local (intestinal) immune defense in young pigs.Key words: postnatal ontogenesis, small intestine, immunomodulating molecules (VIP, SP and NOS), pig.  相似文献   
75.
A reference Y-chromosome short tandem repeat (STR) haplotype database is needed for Y-STR match interpretation as well as for national and regional characterization of populations. The aim of this study was to create a comprehensive Y-STR haplotype database of the Croatian contemporary population and to analyze substructure between the five Croatian regions. We carried out a statistical analysis of the data from previously performed genetic analyses collected during routine forensic work by the Forensic Science Centre "Ivan Vu?eti?". A total of 1,100 unrelated men from eastern, western, northern, southern and central Croatia were selected for the purpose of this study. Y-STRs were typed using the AmpFISTR Yfiler PCR amplification kit. Analysis of molecular variance calculated with the Y chromosome haplotype reference database online analysis tool included 16 population samples with 20,247 haplotypes. A total of 947 haplotypes were recorded, 848 of which were unique (89.5%). Haplotype diversity was 0.998, with the most frequent haplotype found in 9 of 1,100 men (0.82%). Locus diversity varied from 0.266 for DYS392 to 0.868 for DYS385. Discrimination capacity was 86.1%. Our results suggested high level of similarity among regional subpopulations within Croatia, except for mildly different southern Croatia. Relative resemblance was found with Bosnia and Herzegovina and Serbia. Whit Atheys' Haplogroup Predictor was used to estimate the frequencies of Y-chromosome haplogroups. I2a, R1a, E1b1b and R1b haplogroups were most frequent in all Croatian regions. These results are important in forensics and contribute to the population genetics and genetic background of the contemporary Croatian population.  相似文献   
76.
Results of our study describe the long term effects of reduction mammaplasty. Many women with excessively small or large breasts have an altered personal self-image and often suffer from low self-esteem and other psychological stresses. This procedure is designed to reduce and reshape large breasts, and since the size, shape, and symmetry of a woman's breasts can have a profound effect on her mental and physical well-being it is important to observe the patient's long-term outcome. Currently, breast reduction surgery is safe, effective and beneficial to the patient. In Croatia, reduction mammoplasty is often excluded from the general health care plan. The distinction between "reconstructive" versus "cosmetic" breast surgery is very well defined by the American Society of Plastic Surgeons Board of Directors. Unfortunately, the Croatian Health Society has yet to standardize such a distinction. There is an imperative need for evidence-based selection criteria. We retrospectively analyzed data of 59 female patients suffering from symptomatic macromastia who underwent reduction mammaplasty over a 16 year period (1995 until 2011). Our aim was to compare and contrast the various techniques available for reduction mammaplasty and to determine, based on patient outcome and satisfaction, which technique is most suited for each patient. The results of our study generally reinforce the observation that reduction mammaplasty significantly provides improvements in health status, long-term quality of life, postsurgical breast appearance and significantly decrease physical symptoms of pain. A number of 59 consecutive cases were initially treated with the four different breast reduction techniques: inverted-T scat or Wisa pattern breast reduction, vertical reduction mammaplasty, simplified vertical reduction mammaplasty, inferior pedicle and free nipple graft techniques. The average clinical follow-up period was 6-months, and included 48 patients. The statistical analysis of the postoperative patient complications revealed a significant positive relationship in regards to smoking. The majority of these complications were wound related, with no significant relationship between patient complications and variables such as age, BMI, ASA score, resection weight of breast parenchyma, nipple elevation, duration of surgery, and type of pedicle. The higher number of complication correlated with a lower volume of parenchyma resection (rho=-0.321). Overall satisfaction with the new breast size (79%), appearance of the postoperative scars (87%), overall cosmetic outcome score (91%), overall outcome (100%), psychosocial outcome (46%), sexual outcome (85%), physical outcome (88%), satisfaction with preoperative information data (92%), and finally satisfaction with overall care process (96%) was calculated. As expected, the physical symptoms disappeared or were minimized in 88% of patients. Each method of breast reduction has its advantages and disadvantages. The surgeon should evaluate each patient's desires on the basis of her physical presentation. Breast reduction surgery increases the overall personal and social health; not only for the patient, but for their family and friends as well. It is an imperative that every surgeon is aware of this, in order to provide the highest level of care and quality to their patients.  相似文献   
77.
The toxicity of n-butanol in microbial fermentations limits its formation. The stress response of Clostridium acetobutylicum involves various stress proteins and therefore, over-expression of genes encoding stress proteins constitutes an option to improve solvent tolerance. Over-expression of groESL, grpE and htpG, significantly improved butanol tolerance of C. acetobutylicum. Whereas the wild type and vector control strain did not survive 2?% (v/v) butanol for 2?h, the recombinant strains showed 45?% (groESL), 25?% (grpE) and 56?% (htpG), respectively, of the initial c.f.u. after 2?h of butanol exposure. As previously, over-expression of groESL led to higher butanol production rates, but the novel strains over-expressing grpE or htpG produced only 51 and 68?%, respectively, of the wild type butanol concentrations after 72?h clearly differentiating butanol tolerance and production. Not only butanol tolerance but also the adaptation to butanol in successive stress experiments was significantly facilitated by increased levels of GroESL, GrpE and HtpG. Re-transformation and sequence analyses of the plasmids confirmed that not the plasmids, but the host cells evolved to a more robust phenotype.  相似文献   
78.

Background

Infraorbital nerve constriction (IoNC) is an experimental model of trigeminal neuropathy. We investigated if IoNC is accompanied by dural extravasation and if botulinum toxin type A (BoNT/A) can reduce pain and dural extravasation in this model.

Methodology/Principal Findings

Rats which developed mechanical allodynia 14 days after the IoNC were injected with BoNT/A (3.5 U/kg) into vibrissal pad. Allodynia was tested by von Frey filaments and dural extravasation was measured as colorimetric absorbance of Evans blue - plasma protein complexes. Presence of dural extravasation was also examined in orofacial formalin-induced pain. Unilateral IoNC, as well as formalin injection, produced bilateral dural extravasation. Single unilateral BoNT/A injection bilaterally reduced IoNC induced dural extravasation, as well as allodynia (lasting more than 2 weeks). Similarly, BoNT/A reduced formalin-induced pain and dural extravasation. Effects of BoNT/A on pain and dural extravasation in IoNC model were dependent on axonal transport through sensory neurons, as evidenced by colchicine injections (5 mM, 2 µl) into the trigeminal ganglion completely preventing BoNT/A effects.

Conclusions/Significance

Two different types of pain, IoNC and formalin, are accompanied by dural extravasation. The lasting effect of a unilateral injection of BoNT/A in experimental animals suggests that BoNT/A might have a long-term beneficial effect in craniofacial pain associated with dural neurogenic inflammation. Bilateral effects of BoNT/A and dependence on retrograde axonal transport suggest a central site of its action.  相似文献   
79.
A young Griffon vulture died with signs of convulsion, vomiting, tremor, seizures propulsions and lack of co-ordination. Toxicological analysis of the stomach content revealed the presence of methomyl (9.3 mg/kg), methomyloxime (6.7 mg/kg) and deltamethrin (6.1 mg/kg). Concentrations of methomyl and its intermediate methomyloxime, combined with results of other analysis, indicate methomyl as the cause of death of this bird.  相似文献   
80.
Zdravko Baruch   《Flora》2005,200(1):49-64
The seasonal savannas dominated by the C4 grasses of the genus Trachypogon, are widespread in northern South America. In Venezuela, they extend from the central lowland Llanos to intermediate elevations in the Coastal and Andean Mountains and to the Guiana Plateau (Gran Sabana) in the south. This study aims to classify these savannas and to understand the environmental factors that determine their composition and structure. Thirty-seven sites were sampled, plant cover and density were measured in 376 one square meter quadrats and the importance value index (IVI) was calculated. Climate data were obtained from climatological stations and soil properties were analyzed. The results were classified by clustering and TWINSPAN. Floristic and environmental data were ordered with the canonical correspondence analysis (CCA).Trachypogon savannas are heterogeneous, both floristically and environmentally. An altitudinal gradient of 2000 m separates the intermediate elevation Coastal Mountains (Type I) and the Guiana savannas (Type II) from the lowland Llanos. In the lowlands, sparsely covered and treeless communities on extremely oligotrophic and sandy soils (Type IV) differ structurally and floristically from woody savannas (Type III). The floristics and structure of the savannas respond directly or indirectly to elevation and water and nutrient availability. These responses were evidenced by: (a) floristic composition, as Neotropical lowland savanna species merged with those of the Andean sub-páramo in Type I savannas or with those from the Guianan flora in Type II savannas. (b) Species richness, which ranged from an average of 13.8 per site in sandy Type IV savannas to 38.9 per site in Type I intermediate elevation savannas. (c) Community physiognomy, which changes from an homogeneous herbaceous matrix with dispersed trees in Type III savannas to a shrubby Type I savannas to “treeless” Types II and IV savannas. (d) Plant cover which varied from 93.8% in the fertile Type I savannas to around 80% in the sandy oligotrophic savannas of Types II and IV. Each savanna type is related to one of the major geomorphological regions of Venezuela.  相似文献   
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