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51.

Background and purpose

To evaluate the current status of radiotherapy facilities, staffing, and equipment, treatment and patients in Poland for the years 2005–2011 following implementation of the National Cancer Programme.

Methods

A survey was sent to the radiotherapy centres in Poland to collect data on available equipment, staffing, and treatments in the years 2005–2011.

Results

In 2011, 76,000 patients were treated with radiotherapy at 32 centres vs. 63,000 patients at 23 centres in 2005. Number of patients increased by 21%. In 2011, there were 453 radiation oncologists – specialists (1 in 168 patients), 325 medical physicists (1 in 215 patients), and 883 radiotherapy technicians (1 in 86 patients) vs. 320, 188, and 652, respectively, in 2005. The number of linear accelerators increased by 60%, from 70 units in 2005 to 112 in 2011. The current linac/patient ratio in Poland is 1 linac per 678 patients. Waiting times from diagnosis to the start of treatment has decreased.

Conclusion

Compared to 2005, there are more treatment facilities, more and better equipment (linacs), and more cancer care specialists. There are still large differences between the 16 Polish provinces in terms of equipment availability and ease of access to treatment. However, radiotherapy services in Poland have improved dramatically since the year 2005.  相似文献   
52.
Insertion of bone substitution materials accelerates healing of osteoporotic fractures. Biodegradable materials are preferred for application in osteoporotic patients to avoid a second surgery for implant replacement. Degraded implant fragments are often absorbed by macrophages that are removed from the fracture side via passage through veins or lymphatic vessels. We investigated if lymphatic vessels occur in osteoporotic bone defects and whether they are regulated by the use of different materials. To address this issue osteoporosis was induced in rats using the classical method of bilateral ovariectomy and additional calcium and vitamin deficient diet. In addition, wedge-shaped defects of 3, 4, or 5 mm were generated in the distal metaphyseal area of femur via osteotomy. The 4 mm defects were subsequently used for implantation studies where bone substitution materials of calcium phosphate cement, composites of collagen and silica, and iron foams with interconnecting pores were inserted. Different materials were partly additionally functionalized by strontium or bisphosphonate whose positive effects in osteoporosis treatment are well known. The lymphatic vessels were identified by immunohistochemistry using an antibody against podoplanin. Podoplanin immunopositive lymphatic vessels were detected in the granulation tissue filling the fracture gap, surrounding the implant and growing into the iron foam through its interconnected pores. Significant more lymphatic capillaries were counted at the implant interface of composite, strontium and bisphosphonate functionalized iron foam. A significant increase was also observed in the number of lymphatics situated in the pores of strontium coated iron foam. In conclusion, our results indicate the occurrence of lymphatic vessels in osteoporotic bone. Our results show that lymphatic vessels are localized at the implant interface and in the fracture gap where they might be involved in the removal of lymphocytes, macrophages, debris and the implants degradation products. Therefore the lymphatic vessels are involved in implant integration and fracture healing.  相似文献   
53.
Among the neuronal binding partners of calmodulin (CaM) are Munc13 proteins as essential presynaptic regulators that play a key role in synaptic vesicle priming and are crucial for presynaptic short-term plasticity. Recent NMR structural investigations of a CaM/Munc13-1 peptide complex have revealed an extended structure, which contrasts the compact structures of most classical CaM/target complexes. This unusual binding mode is thought to be related to the presence of an additional hydrophobic anchor residue at position 26 of the CaM binding motif of Munc13-1, resulting in a novel 1-5-8-26 motif. Here, we addressed the question whether the 1-5-8-26 CaM binding motif is a Munc13-related feature or whether it can be induced in other CaM targets by altering the motif''s core residues. For this purpose, we chose skeletal muscle myosin light chain kinase (skMLCK) with a classical 1-5-8-14 CaM binding motif and constructed three skMLCK peptide variants mimicking Munc13-1, in which the hydrophobic anchor amino acid at position 14 was moved to position 26. Chemical cross-linking between CaM and skMLCK peptide variants combined with high-resolution mass spectrometry yielded insights into the peptides'' binding modes. This structural comparison together with complementary binding data from surface plasmon resonance experiments revealed that skMLCK variants with an artificial 1-5-8-26 motif cannot mimic CaM binding of Munc13-1. Apparently, additional features apart from the spacing of the hydrophobic anchor residues are required to define the functional 1-5-8-26 motif of Munc13-1. We conclude that Munc13 proteins display a unique CaM binding behavior to fulfill their role as efficient presynaptic calcium sensors over broad range of Ca2+ concentrations.  相似文献   
54.
Mechanochemical synthesis of Cu3P in the presence of n‐dodecane results in a material with a secondary particle size distribution of 10 μm, secondary particles which consist of homogeneously agglomerated 20 nm primary particles. The electrochemical performance of Cu3P with lithium is influenced by the reaction depth, in other words by the lower potential cut‐off. During the electrochemical reaction, the displacement of copper by lithium from the Cu3P structure until the formation of Li3P and Cu deteriorates the capacity retention. Improved performance was obtained when the charge potential was limited to 0.50 V (vs. Li/Li+) and the formation of the LixCu3‐xP phase (0 ≤ × ≤ 2). In this case, when the potential is limited to 0.5 V, the capacity is stable for more than 50 cycles. Acceptable electrochemical performances in Li‐ion cells within the voltage range 0.50–2.0 V (vs. Li/Li+) were shown when Cu3P was used as an anode and Li1.2(Ni0.13Mn0.54Co0.13)O2 and LiNi0.5Mn1.5O4 as positive electrode materials.  相似文献   
55.
56.
Prostate cancer (PCa) is the most common type of cancer in men in the United States, which disproportionately affects African American descents. While metastasis is the most common cause of death among PCa patients, no specific markers have been assigned to severity and ethnic biasness of the disease. MicroRNAs represent a promising new class of biomarkers owing to their inherent stability and resilience. In the present study, we investigated potential miRNAs that can be used as biomarkers and/or therapeutic targets and can provide insight into the severity and ethnic biasness of PCa. PCR array was performed in FFPE PCa tissues (5 Caucasian American and 5 African American) and selected differentially expressed miRNAs were validated by qRT-PCR, in 40 (15 CA and 25 AA) paired PCa and adjacent normal tissues. Significantly deregulated miRNAs were also analyzed in urine samples to explore their potential as non-invasive biomarker for PCa. Out of 8 miRNAs selected for validation from PCR array data, miR-205 (p<0.0001), mir-214 (p<0.0001), miR-221(p<0.001) and miR-99b (p<0.0001) were significantly downregulated in PCa tissues. ROC curve shows that all four miRNAs successfully discriminated between PCa and adjacent normal tissues. MiR-99b showed significant down regulation (p<0.01) in AA PCa tissues as compared to CA PCa tissues and might be related to the aggressiveness associated with AA population. In urine, miR-205 (p<0.05) and miR-214 (p<0.05) were significantly downregulated in PCa patients and can discriminate PCa patients from healthy individuals with 89% sensitivity and 80% specificity. In conclusion, present study showed that miR-205 and miR-214 are downregulated in PCa and may serve as potential non-invasive molecular biomarker for PCa.  相似文献   
57.

Background

Depression is a common disorder affecting 10–15% women in the postpartum period. Postpartum depression can disrupt early mother-infant interaction, and constitutes a risk factor for early child development. Recently, attention has been drawn to the hypothesis that a low intake of seafood in pregnancy can be a risk factor for postpartum depression. Seafood is a unique dietary source of the marine omega-3 fatty acids and is a natural part of a healthy balanced diet that is especially important during pregnancy.

Methods

In a community based prospective cohort in a municipality in Western Norway, we investigated both nutritional and psychological risk factors for postpartum depression. The source population was all women who were pregnant within the period November 2009 - June 2011. The fatty acid status in red blood cells was assessed in the 28th gestation week and participants were screened for postpartum depression using the Edinburgh Postnatal Depression Scale (EPDS) three months after delivery. The aim of the present study was to investigate if a low omega-3 index in pregnancy is a possible risk factor for postpartum depression.

Results

In a simple regression model, the omega-3 index was associated with the EPDS score in a nonlinear inverse manner with an R square of 19. Thus, the low omega-3 index explained 19% of the variance in the EPDS score. The DPA content, DHA content, omega-3 index, omega-3/omega-6 ratio, total HUFA score, and the omega-3 HUFA score were all inversely correlated with the EPDS score. The EPDS scores of participants in the lowest omega-3 index quartile were significantly different to the three other omega-3 index quartiles.

Conclusion

In this study population, a low omega-3 index in late pregnancy was associated with higher depression score three months postpartum.  相似文献   
58.
The formation of mixed-species social groups, whereby heterospecifics form and maintain either transient or stable groups with each other, can confer substantial fitness benefits to individuals. Such benefits may arise via multiple mechanisms associated with both predation avoidance and foraging efficiency. In fishes, mixed-species shoaling reportedly occurs where displaced tropical species (known as “vagrants”) interact with resident temperate species, although little is known about the nature and frequency of such interactions. To investigate this phenomenon, we used displaced tropical Indo-pacific Sergeant Abudefduf vaigiensis settling in temperate south-eastern Australia as a model system. Underwater visual surveys revealed shoal composition and size differed significantly between open-water and reef habitats, with shoals in open habitats being larger and more speciose. Shoals containing A. vaigiensis were mainly mixed-species, and larger and more speciose in open habitats than nearer to reef. Since both foraging efficiency (via access to plankton) and predation threat likely increase with increasing distance from reef habitat, we suggest that mixed-species shoaling mitigates predation risk whilst allowing increased foraging opportunities for A. vaigiensis in open areas. These findings provide support for the importance of mixed-species shoaling to the persistence of tropical reef fishes in temperate regions.  相似文献   
59.
Recent studies suggest that Candida albicans colonization is associated with several gastrointestinal inflammatory disorders and is also responsible for the delay in ulcer healing. No data are reported about the effects of C. albicans on the nonsteroidal anti-inflammatory drugs (NSAIDs)-induced necroinflammatory lesions. On the other hand, beneficial effects of NSAIDs regarding the colonization potential with C. albicans have been reported. Our aim was to investigate whether the association between NSAIDs and C. albicans could potentially induce necroinflammatory lesions in the guinea pigs gastric and enteral mucosa. Three interventional groups of 11 guinea pigs each were investigated after 5 days of receiving indomethacin, C. albicans or the association of both. C. albicans and necroinflammatory lesions were graded based on histological examinations. Statistical analysis used Mann–Whitney nonparametric test. NSAIDs did not significantly decrease C. albicans colonization grades on gastrointestinal mucosa. Administration of indomethacin subsequent to C. albicans determined significantly more severe necroinflammatory lesions compared to group that only received C. albicans. The association of NSAIDs and C. albicans did not cause significantly more severe degenerative or inflammatory lesions compared to the administration of only NSAIDs in this experimental model. Associations between NSAIDs and C. albicans caused significantly more severe necroinflammatory injuries than the lesions produced by C. albicans, without enhancing the mucosal injury or inflammation caused by NSAIDs.  相似文献   
60.
ABSTRACT

Recent evidence supports the important role of the circadian system in cancer progression in humans. The aim of the present study is to evaluate clock (cry1, cry2 and per2) and clock-controlled (vascular endothelial growth factor-a, early growth response protein 1 and estrogen receptor β) gene expression in colorectal cancer and adjacent tissue and identify a possible link between survival of patients and expression of above mentioned genes. The study includes 64 patients of both sexes with previously diagnosed colorectal cancer. RNA was extracted from the tumor tissue and adjacent parts of the resected colon, and real-time PCR was used for detection of clock gene expression. Expression of cry2 and per2 was significantly downregulated in tumor tissue compared to adjacent tissues. After splitting of the cohort according to sex, we detected downregulated levels of cry2 and per2 in male patients, but not in females. Splitting of male and female sub-cohorts according to presence of metastases revealed significant donwregulation of cry2 expression in female patients without distant metastasis. Better survival rate was associated with low expression of cry2 in female patients. Moreover, we observed an increase in cry1 expression in female patients with distant metastases in tumor compared to adjacent tissue. Accordingly, women with high expression of cry1 in tumor tissue displayed worse survival, which was not observed in men. Taken together, expression of clock and clock-controlled genes in tumors of males and females clustered according to presence of distant metastases correlated with survival analysis. Studied clock-controlled genes also showed sex-dependent changes. Low expression of vegf-a in tumor correlated with better survival in men but not in women. High expression of estrogen receptor β mRNA was related to better survival in women but not in men. Low expression of vegf-a, egr1 and estrogen receptor β was associated with worse survival in women compared to men. Our data indicate sex-dependent associations between clock and clock-controlled gene expression in cancer tissue and patient’s survival prognosis.  相似文献   
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