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991.
992.

Introduction

The modern literature is producing a rapidly growing number of articles which highlight the relationship between infection and lumbar disc degeneration. However, the means by which samples are collected is questionable. Posterior approach surgery is not free from skin contamination. The possibility of intraoperative contamination of disc biopsies cannot be excluded.

Objective

The objective of this study was to determine if an association existed between lumbar disc degeneration and chronic infection of the intervertebral disc.

Materials and methods

313 patients (186/127, F/M) with chronic low back pain secondary to degenerative disc disease which was resistant to medical treatment were included in a single-centre prospective study. All underwent a lumbar anterior video-assisted minimally invasive fusion or disc prosthesis in L4–L5 and/or L5–S1 via an anterior retroperitoneal approach. The patients MRI scans demonstrated in Pfirrmann's classification grade IV or V disc degeneration; 385 disc drives were taken. In terms of Modic changes, 303 Modic 1, 58 Modic II and 24 absence of Modic change, respectively. All underwent intraoperative biopsy, performed according to a strict aseptic protocol. The biopsies were then cultured for 4 weeks with specialised enrichment cultures and subjected to histopathological analysis.

Results

The mean age was 47 ± 8.6 years sterile cultures were obtained in 379 samples (98.4 %) and 6 were positive (1.6 %). The cultured bacteria were: Propionibacterium acnes (n:2), Staphylococcus epidermidis (n:2), Citrobacter freundii (n:1), and Saccharopolyspora hirsuta (n:1). Histopathological analysis did not demonstrate any evidence of a neutrophilia. There were no delayed or secondary infections.

Discussion and conclusion

Unlike the posterior approach where contamination is common, the anterior video-assisted approach allows a biopsy without skin contact. This approach to the spine is the most effective way to eliminate the risk of contamination. Our results confirm the absence of any relationship between infection and disc degeneration. We suggest that the 6 positive samples in our study may be related to contamination. The absence of infection at 1-year followup is an additional argument in favour of our results. In conclusion, our study shows no association between infection and disc degeneration. The pathophysiology of disc degeneration is complex, but the current literature opens new perspectives.
  相似文献   
993.
994.
995.
The course of autosomal dominant polycystic kidney disease (ADPKD) varies among individuals, with some reaching ESRD before 40 years of age and others never requiring RRT. In this study, we developed a prognostic model to predict renal outcomes in patients with ADPKD on the basis of genetic and clinical data. We conducted a cross-sectional study of 1341 patients from the Genkyst cohort and evaluated the influence of clinical and genetic factors on renal survival. Multivariate survival analysis identified four variables that were significantly associated with age at ESRD onset, and a scoring system from 0 to 9 was developed as follows: being male: 1 point; hypertension before 35 years of age: 2 points; first urologic event before 35 years of age: 2 points; PKD2 mutation: 0 points; nontruncating PKD1 mutation: 2 points; and truncating PKD1 mutation: 4 points. Three risk categories were subsequently defined as low risk (0–3 points), intermediate risk (4–6 points), and high risk (7–9 points) of progression to ESRD, with corresponding median ages for ESRD onset of 70.6, 56.9, and 49 years, respectively. Whereas a score ≤3 eliminates evolution to ESRD before 60 years of age with a negative predictive value of 81.4%, a score >6 forecasts ESRD onset before 60 years of age with a positive predictive value of 90.9%. This new prognostic score accurately predicts renal outcomes in patients with ADPKD and may enable the personalization of therapeutic management of ADPKD.  相似文献   
996.
It is widely accepted that elevated protease activity (EPA) in chronic wounds impedes healing. However, little progress has occurred in quantifying the level of protease activity that is detrimental for healing. The aim of this study was to determine the relationship between inflammatory protease activity and wound healing status, and to establish the level of EPA above which human neutrophil‐derived elastase (HNE) and matrix metalloproteases (MMP) activities correlate with nonhealing wounds. Chronic wound swab samples (n = 290) were collected from four wound centers across the USA to measure HNE and MMP activity. Healing status was determined according to percentage reduction in wound area over the previous 2–4 weeks; this was available for 211 wounds. Association between protease activity and nonhealing wounds was determined by receiver operating characteristic analysis (ROC), a statistical technique used for visualizing and analyzing the performance of diagnostic tests. ROC analysis showed that area under the curve (AUC) for HNE were 0.69 for all wounds and 0.78 for wounds with the most reliable wound trajectory information, respectively. For MMP, the corresponding AUC values were 0.70 and 0.82. Analysis suggested that chronic wounds having values of HNE >5 and/or MMP ≥13, should be considered wound healing impaired. EPA is indicative of nonhealing wounds. Use of a diagnostic test to detect EPA in clinical practice could enable clinicians to identify wounds that are nonhealing, thus enabling targeted treatment with protease modulating therapies.  相似文献   
997.

Background

Transjugular intrahepatic portosystemic shunt (TIPS) is the standard procedure in the treatment of refractory ascites and variceal bleeding in the setting of portal hypertension. Secondary obstruction of the shunt is a classic but potentially lethal complication.

Methods

We present here the case of a cirrhotic patient that underwent a TIPS for refractory ascites, with early complete thrombosis without lethal complication.

Results

Obstruction of the TIPS led to thrombosis of both the right hepatic and the right portal veins with progressive total atrophy of the right liver and marked hypertrophy of the left liver. Despite initial poor liver function, biological hepatic markers improved slowly until complete recovery.

Conclusion

Hence, we suggest the concept of combined right portal and hepatic vein embolization as a new procedure to induce partial liver hypertrophy before major liver resection, even in cirrhotic patients.
  相似文献   
998.
目的分析先天性肠闭锁病例的诊断及治疗,以提高治愈率及术后生活质量。方法回顾性分析166例先天性肠闭锁的临床资料。结果治愈142例,治愈率85.5%(142/166),其中包括18例二期手术治愈者;术中10例、术后8例放弃治疗;术后死亡6例。结论早期诊断和选择合理的术式是提高肠闭锁治愈率的关键,基础支持及手术技术改进能促进病情的恢复,改善预后。  相似文献   
999.
顺铂通过激活p53信号通路抑制人食管癌细胞的生存   总被引:1,自引:1,他引:0  
研究顺铂抑制人食管癌细胞生存的作用及其机制。细胞活力实验检测顺铂对食管癌亲代细胞EC109及耐药细胞EC109/CDDP的杀伤作用。Western blot检测顺铂处理后食管癌亲代细胞EC109及耐药细胞EC109/CDDP的p53和Phospho-p53(Ser15)的蛋白表达。克隆存活实验检测顺铂单独及联合p53抑制剂Pifithrin-α对食管癌亲代细胞EC109及耐药细胞EC109/CDDP生存的影响。实验结果显示,与亲代细胞EC109比较,耐药细胞EC109/CDDP保持了对顺铂的耐药性,IC50分别是(20.4±4.4)μmol/L和(5.7±0.1)μmol/L。在亲代和耐药人食管癌细胞,顺铂不改变p53蛋白的表达,但增加了p53蛋白在Ser15位磷酸化水平。顺铂抑制了EC109及耐药细胞EC109/CDDP细胞的生存能力,而p53抑制剂Pifithrin-α在亲代细胞和耐药细胞不同程度的拮抗了顺铂的这一作用。顺铂通过激活p53信号通路,抑制了人食管癌细胞的生存。  相似文献   
1000.

Background

In many countries in Asia, the HIV epidemic is in a concentrated phase, with high prevalence in certain risk groups, such as men who inject drugs. There is also a rapid increase of HIV among women. The latter might be due to high levels of sero-discordant couples and increasing transmission from male to female partners over time.

Methods

All adult married patients initiating antiretroviral treatment at four out-patient clinics in Quang Ninh province in north-eastern Vietnam between 2007 and 2009 were asked to participate in the study. Clinical information was extracted from patients’ records, and a structured questionnaire was used to collect social, demographic and economic data.

Results

Two hundred eighty-eight married patients for whom information on the HIV status of their spouse was available were included in the study. Overall, the sero-discordance rate was 58%. The sero-discordance rate was significantly higher among married males, 71% had spouses not infected, than married females, of whom 18% had spouses not infected. Other factors associated with a high rate of sero-discordance were injection drug use (IDU) history, tuberculosis (TB) history and the availability of voluntary counselling and testing (VCT) in residential locations. High sero-concordance was associated with college/university education.

Conclusion

The sero-discordance was significantly higher among married males than married females. Other factors also related to high sero-discordance were history of IDU, history of TB and the availability of VCT in residential locations. In contrast, college/university education and female sex were significantly related to low sero-discordance. To contain the increasing HIV prevalence among women, measures should be taken to prevent transmission among sero-discordant couples. Trial registration NCT01433601
  相似文献   
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