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21.
BackgroundCytomegalovirus (CMV) reactivation remains one of the most frequent complications after allogeneic hematopoietic stem cell transplantation (HSCT).MethodsAn analysis of the pre-transplant risk factors of CMV reactivation was performed in 98 patients aged 0.5–22 years (median 10.5) undergoing allogeneic HSCT. CMV reactivation was tested by assessing viral load using PCR method. Following factors were analyzed: type of conditioning, graft source, donor type, use of T-depletion and CMV-serostatus of the donor and recipient. Each factor was assigned from 0 to 2 points. Based on total score for each patient, CMV reactivation risk scale was developed, and two groups with low (LR) and high (HR) risk were determined.ResultsCMV reactivation was seen in 25 patients (24.5%). The significant risk factors for CMV reactivation were: CMV-positive recipient (p<0.001), unrelated donor (p<0.002), use of ATG (p<0.002) and PBSC (p<0,01). In the HR group the incidence of reactivation CMV was significantly higher than in LR group (47.8% vs. 5.4%, p<0.001).ConclusionsCMV seropositivity of the recipient was an independent predictor factor of CMV reactivation. The use of risk point scale of CMV reactivation allows for identification of patients with the higher risk of CMV reactivation.  相似文献   
22.
European Journal of Clinical Microbiology & Infectious Diseases - In order to improve the diagnosis of giardiasis, fecal samples (high/medium/low concentration of cysts) were processed by the...  相似文献   
23.
Chelicerata, the second largest subphylum of Arthropoda, includes invertebrates with a wide range of body size. Pseudoscorpions are among small or miniature chelicerates which exhibit several morphological, anatomical, and developmental features related to miniaturization, e.g., replacement of book lungs by tracheae, unpaired gonads, and matrotrophic development of the embryos outside the female body, in the brood sac. In this paper, we show the ovary structure of two pseudoscorpion species, Cheiridium museorum and Apocheiridium ferum (Cheiridiidae). Both cheiridiids are one of the smallest pseudoscorpions. The results of our observations conducted in light, transmission electron, and confocal microscopy demonstrate that the ovary of C. museorum and A. ferum, displays a significant structural difference that is unusual for chelicerates. The difference concerns the spatially restricted position of the germarium. We show that such ovary architecture results in a significantly reduced number of growing oocytes and in consequence a reduced number of deposited eggs. A centrally located germarium implies also a modified pattern of ovary development during oocyte growth due to long distance migration of the germline and the accompanying somatic cells. Herein, we postulate that such an ovary structure is related to the pseudoscorpion's small body size and it is a step towards miniaturization in the smaller pseudoscorpions species.  相似文献   
24.
IntroductionCoronavirus disease 2019 (COVID-19) may affect many organs and may be responsible for numerous complications including cardiovascular problems.MethodsWe analysed consecutive patients (n = 51) admitted to the cardiology department between 1st October 2020 and 31st January 2021 due to symptoms which might have reflected cardiovascular complications following COVID-19. We collected data concerning clinical characteristics, results of laboratory tests, echocardiography and 24-hour ambulatory ECG recording.ResultsThe post-COVID-19 complications appeared 1–4 months after disease recovery. Severe cardiovascular complications were observed in 27.5% of hospitalized patients. In comparison to those with mild complications, patients with severe complications had significantly higher prevalence of diabetes (36 vs. 8%; p = 0.01), decrease in ejection fraction (36% vs. 0%, p < 0.001), higher resting heart rate at admission (85 vs. 72 bpm; p < 0.001), and higher levels of C-reactive protein (p = 0.02) and troponin T (17.9 vs. 4.2 pg/ml; p = 0.01). Dyspnoea and exercise intolerance were also more frequent in patients with severe complications.ConclusionsDiabetes, elevated level of CRP and troponin, heart rate variability parameters and worsening of left ventricular ejection fraction are related to the severity of cardiovascular complications following COVID-19 infection.  相似文献   
25.
X‐ray powder diffraction (XRPD) and Fourier transform infrared (FTIR) spectroscopy are used to characterize the morphology of diacrylate polymer networks, obtained by photoinduced homo‐ and copolymerizations. XRPD reveals the presence of three sized groups of microgel agglomerates. The dimensions of the microgel agglomerates (D) and the degree of conversion (DC) are explained by the monomer chemical structure, the strength of hydrogen bonds, and relate to selected polymer mechanical properties. The D value increases and the DC decreases as the strength of the hydrogen bonds increases. Copolymerization with monomers lacking groups forming strong hydrogen bonds results in more homogeneous networks with improved mechanical properties.

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26.

Objectives

Protective vaccinations are the most effective method of prevention of type B virus hepatitis. The aim of the study was to determine whether in children receiving immunosuppressive therapy due to inflammatory systemic connective tissue diseases the protective concentration of the anti-HBs antibodies produced after vaccination against type B virus hepatitis in infancy is maintained.

Material and methods

The concentration of anti-HBs antibodies was assessed in the sera of 50 children with inflammatory connective tissue diseases – 37 girls (74%) and 13 boys (26%), aged 1.5–17.5 years – during the immunosuppressive treatment, which lasted at least 6 months. The control group consisted of 50 healthy children – 28 girls (56%) and 22 boys (44%) aged 2–17 years. All children were vaccinated in infancy with Engerix B vaccine according to the 0–1–6 months schedule. The antibody concentration of ≥ 10 mIU/ml in patients is regarded as protective.

Results

No protective antibody concentrations were found in 25 cases (50%) in the group of diseased children and only in 2 children in the control group (4%).

Conclusions

The concentration of vaccine-induced antibodies should be assessed in children with inflammatory systemic connective tissue diseases and, in case of the absence of a protective concentration, revaccination should be started. The use of glucocorticosteroids, synthetic and biological disease-modifying antirheumatic drugs is no contraindication to vaccination against hepatitis B.  相似文献   
27.

Aims

The level of C-peptide can identify individuals most likely to respond to immune interventions carried out to prevent pancreatic β-cell damage.The aim of the study was to evaluate factors associated with C-peptide levels at type 1 diabetes (T1D) diagnosis.

Methods

This study included 1098 children aged 2-17 with newly recognized T1D. Data were collected from seven Polish hospitals. The following variables were analyzed: date of birth, fasting C-peptide, HbA1c, sex, weight, height, pH at diabetes onset.

Results

A correlation was observed between fasting C-peptide level and BMI-SDS (p?=?0.0001), age (p?=?0.0001), and HbA1c (p?=?0.0001). The logistic regression model revealed that fasting C-peptide ≥0.7 ng/ml at diabetes diagnosis was dependent on weight, HbA1c, pH and sex (p?<?0.0001).Overweight and obese children (n?=?124) had higher fasting C-peptide (p?=?0.0001) and lower HbA1c (p?=?0.0008) levels than other subjects. Girls had higher fasting C-peptide (p?=?0.036) and higher HbA1c (p?=?0.026) levels than boys.

Conclusion

Obese and overweight children are diagnosed with diabetes at an early stage with largely preserved C-peptide levels. Increased awareness of T1D symptoms as well as improved screening and diagnostic tools are important to preserve C-peptide levels. There are noticeable gender differences in the course of diabetes already at T1D diagnosis.  相似文献   
28.
The main objective of the presented preliminary study was the identification of iron-containing phases. Iron-containing phases had accumulated in organic topsoil horizons collected from an area that has long been affected by the steel industry and emissions from power plants. X-ray diffraction and Mössbauer spectroscopy methods were used for the determination of the iron-containing mineral phases in topsoil subsamples which, after two-staged separation, varied in terms of magnetic susceptibility and granulometry. The Mössbauer spectra were recorded using paramagnetic and magnetic components, although the latter occurred only in the strongly magnetic fraction. The central part of spectra was fitted by two doublets (D1 and D2), which were identified as aluminosilicates. Simultaneously, the experimental spectra were described using several Zeeman sextets (Z1, Z2, and Z3) corresponding to the occurrence of hematite and magnetite-like phases with iron in tetrahedral and octahedral sites. Identification of magnetic phases in the tested material, including hematite, led to the conclusion that soil contamination in the studied area was presumably caused by emissions from a nearby power plant. Magnetite-like phases with a different iron content detected in topsoil samples could be related to metallurgical and coking processes, reflecting the specificity of the industrial area from which the samples were taken. The specific composition of the iron-containing aluminosilicates also illustrated the intense and long-lasting impact of the steel and coking industries on the studied area.  相似文献   
29.
Infections that are triggered by the accompanying immunosuppression in patients with burn wounds are very common regardless of age. Among burn patients, the most frequently diagnosed infections include the bacterial ones primarily caused by Pseudomonas aeruginosa or Klebsiella pneumonia, as well as fungal infections with the etiology of Candida spp. or Aspergillus spp. Besides, burn wounds are highly susceptible to viral infections mainly due to the impaired immune responses and defective functions of the immune cells within the wound microenvironment. The most prevalent viruses that invade burn wounds include herpes simplex virus (HSV), cytomegalovirus (CMV), human papilloma virus (HPV), and varicella zoster virus (VZV). Likewise, less prevalent infections such as those caused by the orf virus or Epstein–Barr Virus (EBV) might also occur in immunosuppressed burn patients. Viral infections result in increased morbidity and mortality rates in severely burned patients. Additionally, a positive correlation between the hospitalization duration and the severity of the viral infection has been demonstrated. Viral infections trigger the occurrence of various complications, ranging from mild symptoms to even fatal incidents. Accurate detection of viral infection is of great clinical importance because of the possibility for a quicker introduction of proper treatment therapy and shortening of hospitalization time. The aim of this paper is to provide a comprehensive review of the literature and summarize the findings regarding the most common viral infections in immunosuppressed burn patients.  相似文献   
30.
Polysulfone‐based membranes with excellent chemical resistance and a wet thickness up to 200 μm are obtained via UV curing of unmodified polymers after careful tuning of the photoinitiating system and the crosslinker structure. Combinations of photoinitiator and crosslinker are studied in depth, followed by a characterization of the formed macromolecular structure. The performance of the resulting membranes is then evaluated through long‐term immersion in solvents. Classical depth‐curing acyl phosphine oxide‐based photoinitiators in combination with a pentaacrylate crosslinker are found to be the optimal system.

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