159 research outputs found
Molecular subgroups of adult medulloblastoma: a long-term single-institution study
No full textBackground Recent transcriptomic approaches have demonstrated that there are at least 4 distinct subgroups in medulloblastoma (MB); however, survival studies of molecular subgroups in adult MB have been inconclusive because of small sample sizes. The aim of this study is to investigate the molecular subgroups in adult MB and identify their clinical and prognostic implications in a large, single-institution cohort. Methods We determined gene expression profiles for 13 primary adult MBs. Bioinformatics tools were used to establish distinct molecular subgroups based on the most informative genes in the dataset. Immunohistochemistry with subgroup-specific antibodies was then used for validation within an independent cohort of 201 formalin-fixed MB tumors, in conjunction with a systematic analysis of clinical and histological characteristics. Results Three distinct molecular variants of adult MB were identified: the SHH, WNT, and group 4 subgroups. Validation of these subgroups in the 201-tumor cohort by immunohistochemistry identified significant differences in subgroup-specific demographics, histology, and metastatic status. The SHH subgroup accounted for the majority of the tumors (62%), followed by the group 4 subgroup (28%) and the WNT subgroup (10%). Group 4 tumors had significantly worse progression-free and overall survival compared with tumors of the other molecular subtypes. Conclusions We have identified 3 subgroups of adult MB, characterized by distinct expression profiles, clinical features, pathological features, and prognosis. Clinical variables incorporated with molecular subgroup are more significantly informative for predicting adult patient outcome
Comparison of unilateral and bilateral percutaneous vertebroplasty for osteoporotic vertebral compression fractures: a systematic review and metaanalysis
No full textBackground: The aim of this meta-analysis is to examine the safety and effectiveness of unilateral percutaneous vertebroplasty (PVP) for treatment of osteoporotic vertebral compression fractures (OVCFs) compared with that of bilateral treatment. Methods: The multiple databases including PubMed, Springer, EMBASE, OVID, and China Journal Full-text Database were adopted to search for relevant studies in English or Chinese, and full-text articles involving comparison of unilateral and bilateral PVP surgery were reviewed. Review Manager 5.0 was adopted to estimate the effects of the results among selected articles. Forest plots, sensitivity analysis, and bias analysis for the articles included were also conducted. Results: Finally, 1043 patients were included in the 14 studies, which eventually satisfied the eligibility criteria, and unilateral and bilateral surgeries were 550 and 493, respectively. The meta-analysis suggested that there was no significant difference of VAS score, ODI score, and cement leakage rate (MD = 0.12, 95% CI [-0.03, 0.26], P = 0.11; MD = -1.28, 95% CI [-3.59, 1.04], P = 0.28; RR = 0.89, 95% CI [0.61, 1.29], P = 0.52). The surgery time of unilateral PVP is much less than that of bilateral PVP (MD = -16.67, 95% CI [-19.22, -14.12], P < 0.00001). Patients with bilateral PVP surgery have been injected more cement than patients with unilateral PVP surgery (MD = -1.55, 95% CI [-1.94, -1.16], P < 0.00001). Conclusions: Both punctures provide excellent pain relief and improvement of life quality. We still encourage the use of the unipedicular approach as the preferred surgical technique for treatment of OVCFs due to less operation time, limited X-ray exposure, and minimal cement introduction and extravasation.Scientific Research Foundation for the Returned Overseas Chinese Scholar, Ministry of Education of China [(2015)311]SCI(E)[email protected]
Tracking functional changes in the cancer genome : a molecular genetic analysis of renal and prostatic carcinomas using PCR based techniques by a candidate chromosome and candidate gene approach
No full textRenal cell carcinoma (RCC) is the most common malignancy occurring in the adult kidney. Prostatic carcinoma is the most common male malignancy in most Western countries. Several environmental factors have been suggested to contributed to the tumor genesis but the involvement of genetic factors is also recognized. Here we applied a variety of molecular genetic techniques to characterize somatic and constitutional genetic alterations in patients with these types of tumors. Von Hippel-Lindau disease (VHL) is an autosomal dominant disorder predisposing to the development of RCC. The disease is caused by the germline mutations of the VHL gene located in chromosomal region 3p25. Using PCR /direct DNA sequencing and Southern blot analysis, 7 germline mutations were identified in 10 VHL families (Paper 1). We further showed the importance of VHL mutation analysis both in prognosis of patient and presymptomatic diagnosis of VHL mutation carriers. Particular note was emphasized on the selection of kidney donors from relatives of a possible VHL patient affected by bilateral RCCs.Somatic deletions of the long arm of chromosome 10 were demonstrated in 24% of the RCC analyzed (Paper 2). As the deletion included the PTEN/MMAC 1 gene, mutation analysis was carried out using PCR/direct DNA sequencing. Three single base changes were identified in 3/6 tumors showing loss of the PTEN/MMAC1 region. A homozygous deletion coupled with absent PTEN/MMAC1 expression was detected in the RCC line UOK147. The result suggests the possible importance of PTEN/MMAC1 gene mutation in clinical prognosis of a subset of RCCs.Using PCR/LOH analysis we detected LOH of 13q markers in 18/36 prostatic carcinomas analyzed (Paper 3). Two important regions of deletion were defined, which did not included the Rb I locus at 13q14 or the BRCA2 locus at 13q12. Mutation analysis of the BRCA2 gene in six tumors did not reveal any important mutations. Immunohistochemical analysis of the same tumor materials showed that frequent aberrant pRb expression was correlated with a tetraploid DNA content but not concordant with the loss of the Rb1 gene. The data suggest the existence of yet unidentified tumor suppressor genes on 13q that are important for prostate cancer development.In the same set of prostatic carcinomas, 16q deletions were demonstrated in 75% of tumors (Paper4). Extensive deletions were found in all the metastases while small deletions were also present in 54% of primary tumors. Four important deleted regions were identified and the presence of the terminal 16q deletion was closely correlated with grade, stage and metastases. The location of tandemly arranged classical cadherin genes was coincident with the four important deleted regions. We chose the CDH I gene at 16q22.1 that encodes the E-cadherin protein as the first candidate gene. Mutation analysis of all the 16 coding exons did not find any mutations in the ten tumors showing LOH at the CDH I region. In addition, we also detected frequent reduced or absent E-cadherin expression in the same set of materials. The finding suggests that chromosome 16q deletions are important in the development of prostate cancer metastasis and could potentially be used as a prognostic marker.Using a modified PCR/LOH analysis in sporadic prostatic carcinomas, we found two possible deletions at the putative prostate cancer susceptibility locus HPCX on Xq27-28 (Paper 5). These deletions caused a complete loss of the DNA sequences in the region. The findings further support the importance of this locus in sporadic tumors.The association between the CAG repeats polymorphism in the androgen receptor gene and prostatic carcinomas was analyzed in Swedish and Japanese populations (Paper 6). Both sporadic and familial prostatic carcinomas in Sweden showed association with short CAG repeats whereas sporadic prostatic carcinomas in Japan showed association with long repeats. In both populations the allele AR(CAG)22 showed negative correlation with prostatic carcinomas, and the alleles AR(CAG)21 and AR(CAG)23 showed positive correlation. Compared to Swedish populations, Japanese males more frequently carried AR(CAG)22 and less frequently AR(CAG)21 and AR(CAG)23. This difference in allelic distribution may be part of the genetic background that determines a dramatically lower incidence of clinical prostate cancer in Japan.The present study may contribute to a better understanding of the genetic mechanism for the development of renal and prostatic carcinoma. The results also present the potential of molecular genetic analysis in clinical diagnosis and prognosis of these two common types of urological malignancies.List of scientific papersI. Li C, Weber G, Ekman P, Lagercrantz J, Norlen BJ, Akerstrom G, Nordenskjold M, Bergerheim US. (1998). Germline mutations detected in the von Hippel-Lindau disease tumor suppressor gene by Southern blot and direct genomic DNA sequencing. Hum Mutat. Suppl 1:S31-33. https://pubmed.ncbi.nlm.nih.gov/9452032II. Alimov A, Li C, Gizatullin R, Fredriksson V, Sundelin B, Klein G, Zabarovsky E, Bergerheim U. (1999). Somatic mutation and homozygous deletion of PTEN/MMAC1 gene of 10q23 in renal cell carcinoma. Anticancer Res. 19(5B):3841-3846. https://pubmed.ncbi.nlm.nih.gov/10628321III. Li C, Larsson C, Futreal A, Lancaster J, Phelan C, Aspenblad U, Sundelin B, Liu Y, Ekman P, Auer G, Bergerheim US. (1998). Identification of two distinct deleted regions on chromosome 13 in prostate cancer. Oncogene. 16(4):481-487. https://pubmed.ncbi.nlm.nih.gov/9484837IV. Li C, Berx G, Larsson C, Auer G, Aspenblad U, Pan Y, Sundelin B, Ekman P, Nordenskjold M, van Roy F, Bergerheim US. (1999). Distinct deleted regions on chromosome segment 16q23-24 associated with metastases in prostate cancer. Genes Chromosomes Cancer. 24(3):175-182. https://pubmed.ncbi.nlm.nih.gov/10451696V. Li C, Ekman P, Bergerheim U. (1999). Somatic deletion of FRAXE GGC repeats overlapping HPCX locus at Xq28 in sporadic prostate cancer. [Manuscript]VI. Li C, Grönberg H, Matsuyama H, Weber G, Damber J-E, Bergh A, Larsson C, Naito K, Nordenskjöld M, Ekman P, Bergerheim U. (1999). Difference between Japanese and Swedish males in androgen receptor polymorphism associated with prostate cancer. [Submitted]</p
Future weather dataset for fourteen UK sites
No full textAbstractThis Future weather dataset is used for assessing the risk of overheating and thermal discomfort or heat stress in the free running buildings. The weather files are in the format of .epw which can be used in the building simulation packages such as EnergyPlus, DesignBuilder, IES, etc
Cluster Phenomenon of Vertebral Refractures After Percutaneous Vertebroplasty in a Patient With Glucocorticosteroid-Induced Osteoporosis Case Report and Review of the Literature
No full textStudy Design. A case report and literature review. Objective. To describe a rare cluster phenomenon of spontaneous vertebral refractures in a patient with glucocorticosteroid-induced osteoporosis (GIOP) subsequent to percutaneous vertebroplasty (PVP) for the management of initial vertebral compression fractures (VCFs). Summary of Background Data. PVP has become the popular strategy for stabilizing osteoporotic VCFs and obtaining rapid pain alleviation and earlier restoration of mobility in both patients with primary osteoporosis and patients with glucocorticosteroid-induced osteoporosis. However, current data are insufficient to recommend routine use of PVP for VCFs caused by GIOP as recent retrospective studies indicate that the risk of vertebral refractures is much higher in patients with GIOP than those with primary osteoporosis. Methods. We reported a 63-year-old Chinese female with GIOP as well as pulmonary infection who underwent PVP for the management of initial VCFs, experienced the cluster phenomenon of spontaneous vertebral refractures. Results. Within a 4-month period, she underwent a total of 6 PVP operations with 13 cement-augmented vertebral bodies from T5-L5. Eleven refractures after the initial PVP procedures included 3 remote-level fractures, 4 adjacent-level fractures, 1 pincher body fracture, and 3 fractures in previously augmented bodies. The average interval between each PVP operation was 23.6 days. Conclusion. The use of PVP as a therapeutic alternative for the treatment of VCFs in patients with GIOP is still controversial. As seen in our case, even when the management decisions were made in consideration of the patient's pulmonary infection, the outcome was disastrous with the cluster phenomenon of vertebral refractures. Current findings suggest a compelling need for high-quality studies investigating cement augmentation procedures in patients with VCF with GIOP.Clinical NeurologyOrthopedicsSCI(E)PubMed1ARTICLE25E1628-E16323
Navigated 2-level posterior lumbar fusion: a 5-cm-incision procedure
No full textBackground: The current study presents a technique (navigated posterior lumbar fusion) which takes a 5-cm incision to accomplish a 2-level posterior lumbar fusion (PLF) and compared its efficacy and efficiency with those of conventional PLF. Methods: Forty patients who were indicated for 2-level lumbar fusion were included and randomized to either navigated PLF group or conventional PLF group. Blood loss, operation time, incision length, complications, bed rest period, and length of hospitalization were recorded. Oswestry Disability Index (ODI) scoring was also performed for each patient before surgery, 3 months after surgery, and 2 years after surgery. Results: The incision length was significantly shorter in the navigated PLF group than in the conventional PLF group (4.8 vs. 10.9 cm, p = 0.001). Accordingly, the blood loss was also significantly less in the navigated PLF group than in the conventional PLF group (209.0 vs. 334.0 ml, p = 0.047). There was no significant difference in total operation time between the two groups (160.7 vs. 144.4 min, p = 0.116). Compared to the conventional PLF group, the navigated PLF group showed significantly less postoperative blood loss, less time to mobilization, and shorter length of hospital stay. The ODI score improved significantly in the both groups immediately after surgery, and maintained well in the following 2 years. Conclusion: Compared to conventional PLF, navigated PLF proved to be superior with regard to incision length, blood loss, time to mobilization, and shorter length of hospital stay.SCI(E)[email protected]
Augmentation of Pedicle Screw Fixation Strength Using an Injectable Calcium Sulfate Cement An In Vivo Study
No full textStudy Design. An in vivo landrace model of cement augmentation of pedicle screw was established, and axial pull-out tests and histological analysis were performed. Objective. To investigate the long-term in vivo biomechanical performance of pedicle screws augmented with calcium sulfate cement. Summary of Background Data. Little information is available on the long-term biomechanical performance of pedicle screws augmented with calcium sulfate cement in vivo. Methods. Ten pedicle screws were implanted into the lumbar vertebrae of 15 adult females landraces weighing 105 to 115 kg. The pedicle screws were augmented with Polymethyl methacrylate (PMMA), augmented with the calcium sulfate cement, or not augmented. The landraces were randomized into 3 study periods of day 1, 6 weeks, and 12 weeks. At the end of the assigned study periods, the animals were killed and axial pull-out tests and histological analyses were conducted on the isolated specimen vertebrae. Results. No significant difference was found among the 1-day, 6-week, and 12-week control group (P > 0.18), no significant difference was found among the 1-day, 6-week and 12-week PMMA group (P > 0.59), and no significant difference was found among the 1-day, 6-week and 12-week calcium sulfate group (P > 0.27). The maximum POS of the PMMA groups was significantly greater than that of the calcium sulfate groups (P < 0.002), the maximum POS of the calcium sulfate groups was significantly greater than that of the control groups (P < 0.004). Histologically progressive absorption of the calcium sulfate was evident. The bone walls around the screws in the 12-week calcium sulfate group were statistically significantly thicker than that of the 12-week control group and that of the 12-week PMMA group. Conclusion. Results of this study demonstrate that the injectable calcium sulfate cement can significantly improve the immediate POS of pedicle screw fixation, and this effect can be maintained even if the calcium sulfate cement has been absorbed completely, which may result from that the calcium sulfate cement resorption paralleled bone ingrowth.Clinical NeurologyOrthopedicsSCI(E)PubMed17ARTICLE232503-25093
Treatment of Cervicogenic Headache Concurrent With Cervical Stenosis by Anterior Cervical Decompression and Fusion
No full textStudy Design: Retrospective study. Objective: To report the efficacy of anterior cervical decompression and fusion surgery as treatment method for cervicogenic headache (CeH). Summary of Background Data: The exact diagnostic criteria and optimal treatment of CeH is still under investigation. Methods: A total of 34 consecutive patients (mean age 55.8 y) with CeH (in addition to cervical stenosis symptomatology) resistant to nonoperative treatment were treated by anterior cervical decompression and fusion from 1 up to 3 levels and were followed for at least 1 year. Clinical visual analog pain scale for headache, patient satisfaction index as well as radiographic examinations (flexion-extension radiographs and, when diagnosis of fusion status was uncertain, computed tomography) were documented for all patients at regular intervals. Statistical comparisons of outcome measures between different time points of examinations were performed. Results: All patients reported relief of their CeH with mean (range) visual analog pain scale scores as 8.1 (3-9), 2.4 (0-4), and 3.1 (0-5) preoperatively, at 2 months postoperatively, and at the final follow-up, respectively. There was a significant improvement (P < 0.001) of visual analog pain scale score between before surgery and at 2 months postoperatively or at the last follow-up. Thirty patients (88%) reported satisfied with their treatment, whereas 4 patients (12%) were not satisfied with surgery. No major surgical complication was seen and only 1 patient had symptomless pseudoarthrosis. Conclusions: CeH when associated with cervical spinal stenosis of the subaxial spine can improve when stenosis is treated with anterior cervical discectomy and fusion.SCI(E)ARTICLE8E1093-E10973
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