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101.

Objectives

The aim of this study was to retrospectively analyze the influence of a prophylaxis protocol of head and neck tumor (HNT) patients during and after intensity-modulated radiotherapy (IMRT).

Material and method

In this 5-year retrospective study (2009–2013), 70 (m 55, f 15; age range 28–8 years; median 58.7 years) out of 248 HNT patients of the Clinic of Cranio-Maxillofacial and Oral Surgery at the University of Zurich, Switzerland, fulfilled the inclusion criteria. Parameters of investigation were the salivary flow rates, possible dental foci and the dental status, oral side effects of radiotherapy, the prophylaxis protocol, and patient’s compliance to this protocol. The following time points before during and after IMRT (6 weeks) were analyzed: prior to IMRT, 2–4 weeks, 6 weeks and 3, 6, and 12 months after the onset of radiotherapy.

Result

Unstimulated salivary flow rate, pH value of unstimulated salivary, and stimulated salivary flow rate showed a significant reduction over time (p < 0.001). One year after IMRT, both unstimulated and stimulated salivary flow showed a statistically significant lower salivary flow. The number of caries-affected sites per patient was significantly higher for patients with low compliance to the prophylaxis protocol (mean: low compliance 1.36, high compliance 0.26). Almost 75 % of the evaluated patients suffered immediate gustatory change, and 47.1 % showed signs of radiostomatitis through IMRT.

Conclusions

High compliance to the prophylaxis protocol during and after radiotherapy is a key factor for the reduction of radiation side effects on dental hard tissue.

Clinical relevance

High compliance to a monitored prophylaxis program is crucial for patients after head and neck surgery.
  相似文献   
102.
Effects of interleukin-6 on fetal hematopoietic progenitors   总被引:2,自引:0,他引:2  
Gardner  JD; Liechty  KW; Christensen  RD 《Blood》1990,75(11):2150-2155
Effects of interleukin-6 (IL-6) on cycling status and clonogenic maturation of human fetal (cord blood) and adult hematopoietic progenitors were compared. Adult marrow cells were incubated for various lengths of time with various concentrations of IL-6, in a serum- free system, after which tritiated thymidine suicide studies were performed. After incubation of 2 to 5 x 10(6) cells/mL for 4 hours in 5.0 ng IL-6/mL, increased thymidine suicide rates were observed for multipotent progenitors (CFU-Mix), granulocyte-macrophage progenitors (CFU-GM), and erythroid burst-forming units (BFU-E). Similar incubations of fetal cells in IL-6 resulted in similar increases in tritiated thymidine suicide rates. In other studies, IL-6 used alone did not support colony formation from adult progenitors. However, it did support colony formation from fetal CFU-Mix (P less than .05), CFU- GM (P less than .001), and BFU-E (P less than .05). In cultures of adult progenitors, IL-6 acted synergistically with IL-3 to support CFU- Mix colony formation (P less than .001), but synergistic actions on CFU- GM and BFU-E were not seen. In contrast, IL-6 acted synergistically with IL-3 and with GM-CSF to support colony formation by fetal CFU-Mix, CFU-GM, and BFU-E. Thus, IL-6 appears to have a wider spectrum of action on fetal progenitors from cord blood than on adult progenitors; including not only the induction of cycling, but also the support of clonogenic maturation of CFU-Mix, CFU-GM, and BFU-E.  相似文献   
103.

Introduction

Tension‐free mesh repair is currently the gold standard treatment for inguinal hernia. Recent evidence has shown that both open and laparoscopic approaches to inguinal hernia repair can achieve good results. Lots of meshes with different properties are available on the market, but direct comparisons between them are scare. We conducted a prospective randomized controlled trial comparing a partially absorbable lightweight mesh (ULTRAPRO?) and a multifilament polyester anatomical mesh (Parietex?) in laparoscopic total extraperitoneal inguinal hernia repair.

Methods

This study was a single‐center, prospective randomized controlled trial to compare the surgical handling and clinical outcomes between two different types of meshes. All operations were performed using a standardized operative protocol. This study was approved by the Institutional Review Board of the Hong Kong East Cluster Health Service in 2009 (reference number: 2009‐087). The study was registered in the Australian New Zealand Clinical Trial Registry (ACTRN12610000031066).

Results

From October 2009 to August 2011, 85 laparoscopic total extraperitoneal inguinal hernia repairs were performed. The mean mesh handling time was 152 s for the ULTRAPRO group and 206 s for the Parietex group (P = 0.001). There were three cases of seroma formation in the ULTRAPRO group and nine in the Parietex group (P = 0.02). The overall recurrence rate was 2.5%.

Conclusion

It took less time to manipulate the flat mesh (ULTRAPRO) than the anatomical mesh (Parietex) in laparoscopic total extraperitoneal inguinal hernia repair, but the time difference was small. Lightweight mesh and heavyweight mesh offered similar clinical outcomes in terms of discomfort sensation and foreign body sensation during long‐term follow‐up.
  相似文献   
104.
Schibler  KR; Liechty  KW; White  WL; Christensen  RD 《Blood》1993,82(8):2478-2484
We postulated that defective generation of granulocyte colony- stimulating factor (G-CSF) by cells of newborn infants might underlie their deficiencies in upregulating neutrophil production and function during bacterial infection. To test this, we isolated monocytes from the blood of preterm neonates, term neonates, and adults and, after stimulation with various concentrations of interleukin-1 alpha (IL-1 alpha) or lipopolysaccharide (LPS), quantified G-CSF concentrations in cell supernatants and G-CSF mRNA in cell lysates. When stimulated with plateau concentrations of IL-1 alpha for 24 hours, G-CSF concentrations were higher in supernatants of adult cells (8,699 +/- 5,529 pg/10(6) monocytes) than in those from term infants (2,557 +/- 442 pg, P < .05) or from preterm infants (879 +/- 348 pg, P < .05 v adults). When stimulated with plateau concentrations of LPS, supernatants of monocytes from preterm neonates had less G-CSF than did those from term neonates or adults. G-CSF mRNA content was low in cells from preterm infants, higher in those from term infants, and highest in those from adults. On the basis of the in vitro studies, we speculated that serum G-CSF concentrations might be less elevated in neutropenic neonates than in neutropenic adults. Indeed, serum concentrations were relatively low in all nonneutropenic subjects; 92 +/- 34 pg/mL (mean +/- SEM) in 10 preterm neonates, 114 +/- 21 pg/mL in 16 term neonates, and 45 +/- 13 pg/mL in 11 healthy adults. Serum concentrations were not elevated in 7 neutropenic neonates (39 +/- 17 pg/mL) but were in 8 neutropenic adults (2101 +/- 942 pg/mL, P < .05 v healthy adults). Other studies suggested that the lower G-CSF production in neonates is not counterbalanced by a heightened sensitivity of G-CSF--responsive progenitors to G-CSF. Therefore, we speculate that newborn infants, particularly those delivered prematurely, generate comparatively low quantities of G-CSF after inflammatory stimulation, and that this might constitute part of the explanation for their defective upregulation of neutrophil production and function during infection.  相似文献   
105.
Denegri  JF; Rogers  PC; Chan  KW; Sadoway  J; Thomas  JW 《Blood》1981,58(4):675-677
Bone marrow and peripheral blood cells from three newborns with Down's syndrome and transient myeloproliferative disorders were cultured in vitro. In the methylcellulose semiliquid system, normal colony formation with maturation and differentiation into granulocytes and monocyte-macrophages were observed in all three patients. This is different from the growth pattern usually seen in acute nonlymphocytic leukemia. A maternal serum inhibitor of both normal allogeneic GM-CFU and blast cell growth was also demonstrated, but its role in pathogenesis is uncertain. Normal in vitro granulopoiesis may help to differentiate the transient myeloproliferative syndrome from congenital leukemia in newborns with Down's syndrome.  相似文献   
106.
Metachondromatosis is a benign bone disease predominantly observed in the hands and feet of children or young adults demonstrating two different manifestations: a cartilage‐capped bony outgrowth on the surface of the bone called exostosis and ectopic cartilaginous nodules inside the bone called enchondroma. Recently, it has been reported that loss‐of‐function mutations of the SHP2 gene, which encodes the SHP2 protein tyrosine phosphatase, are associated with metachondromatosis. The purpose of this study was to investigate the role of SHP2 in postnatal cartilage development, which is largely unknown. We disrupted Shp2 during the postnatal stage of mouse development in a chondrocyte‐specific manner using a tamoxifen‐inducible system. We found tumor‐like nodules on the hands and feet within a month after the initial induction. The SHP2‐deficient mice demonstrated an exostosis‐like and enchondroma‐like phenotype in multiple bones of the hands, feet, and ribs as assessed by X‐ray and micro‐computed tomography (CT). Histological assessment revealed the disorganization of the growth plate cartilage, a cartilaginous protrusion from the epiphyseal bone, and ectopic cartilage nodules within the bones, which is consistent with the pathological features of metachondromatosis in humans (ie, both exostosis and enchondroma). At molecular levels, we observed an abundant expression of Indian hedgehog protein (IHH) and fibroblast growth factor 2 (FGF2) and impaired expression of mitogen‐activated protein kinases (MAPK) in the affected cartilage nodules in the SHP2‐deficient mice. In summary, we have generated a mouse model of metachondromatosis that includes manifestations of exostosis and enchondroma. This study provides a novel model for the investigation of the pathophysiology of the disease and advances the understanding of metachondromatosis. This model will be useful to identify molecular mechanisms for the disease cause and progression as well as to develop new therapeutic strategies in the future. © 2014 American Society for Bone and Mineral Research.  相似文献   
107.
108.
目的本文以回顾性研究方式比较肥胖与非肥胖男女腹部容积是否呈同等增加。方法比较了11名非肥胖女性、9名非肥胖男性及10名肥胖女性、10名男性的腹部容积。腹部容积用其核磁共振图像资料进行计算,并以独立的t检验进行分析。结果非肥胖女性和男性平均皮下腹部容积分别占平均总腹部容积的22.6±3.5%(均值±标准差)和19.9±4.5%(P〈0.05);而肥胖女性和男性的该数值则分别为53.3±4.3%和37.3±7.7%(P〈0.0001)。女性的平均前皮下腹部容积与平均后皮下腹部容积与男性的相比差异显著(P〈0.0002)。非肥胖女性的平均总腹部容积和平均腹部内脏容积与非肥胖男性的相比明显小(P〈0.001)。仅肥胖女性的平均内脏容积比男性的要小得多(P〈0.0001)。除了平均内脏容积(P〈0.0125)外,肥胖女性的总腹部容积要大于非肥胖女性(P〈0.0001);而肥胖男性的总腹部容积明显大于非肥胖男性(P〈0.0001)。结论非肥胖女性和男性的平均前皮下腹部容积与平均后皮下腹部容积相对较小且相等。肥胖女性总腹部容积的增加大都缘于皮下容积的增大,而肥胖男性总腹部容积的增加则因皮下和内脏容积两者的同时增大。  相似文献   
109.
Autosomal recessive primary microcephaly (MCPH) is caused by mutations in at least eight different genes involved either in cell division or DNA repair. Most mutations are identified in consanguine families from Pakistan, Iran and India. To further assess their genetic heterogeneity and mutational spectra, we have analyzed 57 consanguine Pakistani MCPH families. In 34 MCPH families, we detected linkage to five out of the eight well‐characterized disease loci and identified mutations in 27 families, leaving seven families without mutations in the coding exons of the presumably underlying MCPH genes. In the MCPH cohort 23 families could not be linked to any of the known loci, pointing to remarkable locus heterogeneity. The majority of mutations were found in ASPM followed by WDR62, CENPJ, CEP152 and MCPH1. One ASPM mutation (p.Trp1326*) was found in as many as eight families suggesting a Pakistani founder mutation. One third of the families were linked to ASPM followed by WDR62 confirming previous data. We identified three novel ASPM mutations, four novel WDR62 mutations, one novel MCPH1 mutation and two novel CEP152 mutations. CEP152 mutations have not been described before in the Pakistani population.  相似文献   
110.
Muscular hamartoma is a well‐demarcated tumour composed of smooth muscle and adipose tissue. We report the MRI findings of a patient with benign breast neoplasm. To the best of our knowledge, its appearance has not been previously reported.  相似文献   
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