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1.
Anna B?ogowska Izabella Rzepka-Górska S?awomir Zó?towski 《Gynecological endocrinology》2005,20(5):270-273
OBJECTIVE: Constitutional delay of puberty (CDP) is the absence of secondary sexual features in otherwise healthy girls past the 13th year of life. The aim of the present work was to follow the development of estrogen-dependent sexual features, determine the concentrations of gonadotropins, estradiol and sex hormone-binding globulin (SHBG) in girls with CDP at menarche and compare the findings with normal controls. METHODS: We enrolled 11 girls with CDP and 40 controls. Primary, secondary and tertiary sexual features were studied at menarche +/- 3 months. The size of the ovaries and uterus was measured using transabdominal ultrasound. Maturation of breasts and pubic hair was staged according to Tanner. Concentrations of gonadotropins (follicle-stimulating hormone (FSH), luteinizing hormone) and estradiol were measured with immunoenzymatic methods. For measurement of SHBG, a radioimmunoassay was applied. RESULTS: Menarche in CDP girls usually appeared with Stage IV or V of breast development and Stage IV of pubic hair development according to Tanner. CDP girls demonstrated a significantly smaller volume of the uterine body at menarche compared with controls (p = 0.0004). Significantly lower levels of FSH (p = 0.0363) and estradiol (p = 0.0332), as well as a tendency towards lower levels of SHBG, were revealed in CDP girls at menarche. CONCLUSION: In CDP girls, menarche is accompanied by more mature tertiary sexual features, apparently resulting from longer exposure of estrogen-dependent tissues to the action of bioactive endogenous estrogens. The smaller volume of the uterine body in CDP girls at menarche may be attributed to decreased concentrations of FSH and estradiol, as well as to the possibility of decreased insulin-like growth factor-1 and increased neuropeptide Y levels. 相似文献
2.
The cannabinoid system and immune modulation 总被引:13,自引:0,他引:13
Klein TW Newton C Larsen K Lu L Perkins I Nong L Friedman H 《Journal of leukocyte biology》2003,74(4):486-496
3.
Victor de Carvalho Rodrigues Iara Zanella Guterres Beatriz Pereira Savi Izabella Thaís Silva Gislaine Fongaro Gean Vitor Salmoria 《Viruses》2022,14(11)
Herpes viruses are widespread in the human population and can cause many different diseases. Genital herpes is common and can increase the risk of HIV infection and neonatal herpes. Acyclovir is the most used drug for herpes treatment; however, it presents some disadvantages due to its poor oral bioavailability. In this study, some ethylene vinyl acetate devices with different acyclovir amounts (0, 10, and 20 wt.%) were manufactured by fused filament fabrication in two different geometries, an intrauterine device, and an intravaginal ring. Thermal analyses suggested that the crystallinity of EVA decreased up to 8% for the sample loaded with 20 wt.% of acyclovir. DSC, SEM, and FTIR analyses confirmed that the drug was successfully incorporated into the EVA matrix. Moreover, the drug release tests suggested a burst release during the first 24 h followed by a slower release rate sustained up to 80 days. Biological assays showed the biocompatibility of the EVA/ACV device, as well as a 99% reduction in vitro replication of HSV-1. Finally, the EVA presented a suitable performance for 3D printing manufacturing that can contribute to developing personalized solutions for long-term herpes treatment. 相似文献
4.
The article presents research on ergonomics, biophysical comfort and safety of protective clothing. The resistance of the structural, thermal and mechanical properties of five fabrics (CBXS400, GG200T, Twaron CT736, Dyneema HB26 and T1790C), differing in geometry and raw material composition used in space suits, to dangerous ionizing radiation (β and γ) occurring in space was tested. For both types of radiation, four identical one-time doses in the range of 25–100 kGy were used. The effect of the applied absorbed doses of β and γ radiation on the parameters of textiles influencing ergonomics and safety of the cosmonaut’s work was verified by structural tests (micro-computed tomography and optical microcopy), thermal resistance tests (sweating guarded-hotplate) and strength tests (tensile testing machine). Experimental studies of thermal properties are supplemented with heat transport simulations using the finite volume method performed with 3D models of real textiles. The greatest reduction of thermal resistance for Twaron CT736 (−0.0667 m2·°C·W−1 for 100 kGy of β-radiation) and Dyneema HB26 (−0.0347 m2·°C·W−1 for 50 kGy of β-radiation) is observed. Strength tests have shown that all tested textiles are resistant to both types of radiation. Three textiles were selected to create a three-layer assembly with potential application in a cosmonaut’s glove (Extravehicular Activity—EVA). 相似文献
5.
Weronika Pociej-Marciak Izabella Karska-Basta Marek Ku?niewski Agnieszka Kubicka-Trz?ska Bo?ena Romanowska-Dixon 《Case reports in ophthalmology》2015,6(3):394-400
Purpose
We report here a unique case of a sudden loss of vision as the first symptom of an advanced chronic nephropathy.Methods and Results
A 25-year-old man was referred to the Department of Ophthalmology with sudden visual deterioration presumptively diagnosed as bilateral retinitis. The patient had never been under any medical care before and had never had any clinical signs of any chronic disease. He underwent an ophthalmic examination with optical coherence tomography (OCT). Based on the clinical features, OCT scans and systemic blood pressure (BP) assessment (225/145 mm Hg), the patient was definitely diagnosed with hypertensive retinopathy and choroidopathy due to hypertensive crisis. After urgent diagnostic procedures, the patient was diagnosed with a chronic kidney disease at stage 5 in the course of chronic glomerulonephritis. Immediately, a renal replacement therapy was started and the patient was qualified for renal transplantation.Conclusion
Adolescents with an unclear picture of retinal lesions, who have neither a history nor clinical signs of a systemic disease, should undergo careful systemic screening with BP assessment. A sudden deterioration of vision may be the first symptom of a previously undiagnosed severe systemic disease (very rare chronic) that requires immediate treatment.Key Words: Hypertensive crisis, Hypertensive choroidopathy, Hypertensive retinopathy, Chronic renal failure 相似文献6.
Izabella Uchmanowicz Maria Łoboz-Rudnicka Przemysław Szeląg Beata Jankowska-Polańska Krystyna Łoboz-Grudzień 《Current heart failure reports》2014,11(3):266-273
Considering the increasing age of individuals affected with heart failure (HF), a specific approach to their treatment is required, with more attention paid to geriatric conditions such as poor mobility, multiple disabilities, and cognitive impairment. Frailty is a distinct biological syndrome reflecting decreased physiologic reserve and resistance to stressors. It was shown to occur frequently in patients with heart failure, with the prevalence ranging from 15 to 74 %, depending on the studied population and the method of assessment. We reviewed literature data on the influence of frailty, skeletal abnormalities, comorbidities and geriatric condition on diagnosis, treatment, and outcomes in elderly patients with HF. Identification of frailty in patients with HF is important from the clinical point of view, as this condition exerts unfavorable effects on the course of heart failure. Frailty contributes to a higher frequency of visits to emergency departments, hospitalizations, and mortality in patients with HF. Exercise may improve mobility, and nursing support can be implemented to help the patients adhere to medications. Therefore, frail patients should be diagnosed and treated according to available guidelines, and successfully educated about their condition. 相似文献
7.
Aleksandra Banaszkiewicz Beata Klincewicz Izabella Łazowska‐Przeorek Urszula Grzybowska‐Chlebowczyk Paulina Kąkol Aleksandra Mytyk Anna Kofla Andrzej Radzikowski 《Influenza and other respiratory viruses》2014,8(4):431-435
The aim of this study was to evaluate the influenza vaccination status among paediatric patients with inflammatory bowel disease (IBD) in Poland. This was a questionnaire‐based study. 242 patients with IBD and 142 controls were enrolled in the study. Of patients with IBD, 7·8% received an influenza vaccine, compared to 18·3% of controls (P = 0·0013). There were no statistically significant differences in time from IBD diagnosis, disease activity and in drugs, between vaccinated and non‐vaccinated IBD children. In conclusion, the data of our study demonstrate an alarmingly poor influenza vaccination status in the majority of children with IBD. Therefore, there is an unmet need to implement better influenza vaccination strategies for this group of patients. 相似文献
8.
Jacek Piechota Stanislaw Krukowski Petro Sadovyi Bohdan Sadovyi Sylwester Porowski Izabella Grzegory 《Materials》2021,14(5)
The dissolution of molecular nitrogen in Ga and Fe was investigated by ab initio calculations and some complementary experiments. It was found that the N bonding inside these solvents is fundamentally different. For Ga, it is between Ga4s and Ga4p and N2p states whereas for Fe this is by N2p to Fe4s, Fe4p and Fe3d states. Accordingly, the energy of dissolution of N for arbitrarily chosen starting atomic configurations was 0.535 eV/mol and −0.299 eV/mol for Ga and Fe, respectively. For configurations optimized with molecular dynamics, the difference between the corresponding energy values, 1.107 eV/mol and 0.003 eV/mol, was similarly large. Full thermodynamic analysis of chemical potential was made employing entropy-derived terms in a Debye picture. The entropy-dependent terms were obtained via a normal conditions path to avoid singularity of ideal gas entropy at zero K. Nitrogen solubility as a function of temperature and N pressure was evaluated, being much higher for Fe than for Ga. For K and bar, the N concentration in Ga was at. fr. whereas for Fe, it was at. fr. in very good agreement with experimental data. It indicates that liquid Fe could be a prospective solvent for GaN crystallization from metallic solutions. 相似文献
9.
BACKGROUND: Emerging evidence suggests that kallikrein exerts renoprotective effects independent of its haemodynamic actions. The aim of the current investigation was to delineate the role of kallikrein in the regulation of fibrosis, by 'knocking down' its expression using specific small interfering RNAs (siRNA). METHODS: Rat mesangial cells were treated with 12, 60, 120 nmol/l kallikrein-specific siRNAs. The consequent cellular genotypes and phenotypes were analysed. RESULTS: Western blotting demonstrated that mesangial cells produced a kallikrein protein, which was of a different molecular weight to urinary kallikrein from rats of the same species. Treatment of cells with siRNA resulted in a dose-dependent decrease in kallikrein mRNA levels, which impacted on other components of the kallikrein-kinin system, dose-dependently reducing bradykinin B2 receptor mRNA expression. Kallikrein suppression resulted in significant increases in fibronectin and transforming growth factor-beta protein levels in culture supernatants over control levels. Gelatin zymography demonstrated a siRNA dose-dependent decrease in active MMP-2 enzyme levels. Bradykinin, an effector molecule of the kallikrein system, is known to stimulate tissue plasminogen activator production. Paradoxically, however, tissue plasminogen activator protein levels were augmented with increasing kallikrein mRNA silencing. This was accompanied by a dose-dependent decrease in low-density lipoprotein receptor-related protein mRNA levels, indicating that increased tissue plasminogen activator levels were due to an attenuation of receptor-mediated protease clearance. CONCLUSION: These data lend strong support to the hypothesis that kallikrein exerts antifibrotic, renoprotective effects that are independent of its classical haemodynamic actions. 相似文献
10.
Evidence that the LRRK2 ROC domain Parkinson's disease‐associated mutants A1442P and R1441C exhibit increased intracellular degradation 下载免费PDF全文
Izabella D. Greene Francis Mastaglia Bruno P. Meloni Kristin A. West Joanne Chieng Chris J. Mitchell Wei‐Ping Gai Sherif Boulos 《Journal of neuroscience research》2014,92(4):506-516
Mutations in the leucine‐rich repeat kinase 2 (lrrk2) gene are the leading genetic cause of Parkinson's disease (PD). In characterizing the novel ROC domain mutant A1442P, we compared its steady‐state protein levels, propensity to aggregate, and toxicity with the pathogenic R1441C mutant and wild‐type (WT) LRRK2. Mutant (R1441C and A1442P) and WT LRRK2 fused to green fluorescent protein (GFP) and FLAG were transiently expressed in HEK293 cells using plasmid constructs. Western analysis and fluorescence microscopy consistently demonstrated lower mutant LRRK2 protein levels compared with WT. A time‐course expression study using flow cytometry showed that WT LRRK2 expression increased initially but then plateaued by 72 hr. Conversely, R1441C and A1442P mutant expression attained 85% and 74% of WT levels at 24 hr but fell to 68% and 55% of WT levels by 72 hr, respectively. We found that proteasome inhibition markedly increased mutant LRRK2 to levels approaching those of WT. Taken together, our findings reveal increased intracellular degradation for both mutants. Furthermore, the impact of mutant and WT LRRK2 expression on HEK293 cell viability was assessed under normative and oxidative (hydrogen peroxide) conditions and found not to differ. Expression of WT and mutant LRRK2 protein gave rise to intracellular aggregates of similar appearance and cellular localization. In summary, we provide evidence that the novel A1442P mutant and the previously investigated R1441C pathogenic mutant exhibit increased intracellular degradation, a property reportedly demonstrated for the pathogenic LRRK2 kinase domain mutant I2020T. © 2013 Wiley Periodicals, Inc. 相似文献