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71.
Mitral valve leaflets and chordae have been shown to contain different amounts and proportions of glycosaminoglycans (GAGs) and proteoglycans (PGs) corresponding to in vivo normal or diseased cyclic strain patterns. To understand the effect of cyclic strains on GAG/PG synthesis by valvular interstitial cells (VICs) isolated from valve leaflet and chordae separately, porcine VICs were seeded within collagen gels and alternately stretched or relaxed for 24 h periods for one week in a custom-designed tissue engineering bioreactor. We found cyclic-stretch-induced upregulation of total GAGs and of individual GAG classes secreted into the culture medium. Leaflet cells showed a delayed response to stretching compared to chordal cells, but altered the proportions of various GAG classes they secreted during the culture duration. Decorin and biglycan PGs were slightly responsive to stretch. We demonstrated that mechanical stretch and relaxation conditions reversibly regulate GAG and PG production in a novel 3D model of valve tissues. This is the first study using cyclic strains to modulate GAG/PG synthesis by valve cells and our results may have implications for the remodeling of the mitral valve as well as other tissues.  相似文献   
72.
73.

Introduction

The purpose of this study was to compare the outcome of open treatment of mandibular fracture (symphysis or parasymphysis) using lag screw or mini plate clinically as well as radiologically in young (age range 12–45 years) and healthy individuals of poor socioeconomic status.

Method

This prospective study was conducted on 30 patients diagnosed as cases of displaced mandibular anterior fractures treated with open reduction and internal fixation. The patients were then randomly allocated to either of two groups––Group A: Two 2.5 mm stainless steel lag screws were placed in 15 patients. Group B: Two 2.5 mm stainless steel mini plates were placed in 15 patients for the fixation of fractures. Subsequent follow up was done on 2nd, 4th, 6th and 8th week postoperatively. During every follow up patient was assessed clinically for infection, malocclusion, loosening of plate/screw, sensory disturbance, plate fracture, malunion/non-union, devitalisation of associated dentoalveolar segment and masticatory efficiency. Radiographs were taken if necessary and patients were further assessed for any complaint. Pain was objectively measured using a visual analogue scale, bite force was measured using a bite force transducer at biweekly interval. The data collected was subjected to unpaired t test and paired t test for statistical analysis.

Results

During follow up period a significant improvement in bite force was present in both the groups, with more improvement seen in the lag screw group (p < 0.01). There was a significant pain reduction present in the lag screw group (p < 0.01) and also masticatory efficiency showed a steadier improvement in lag screw group while mini plate group patients showed a tendency to masticate only food items of medium hard consistency.

Conclusion

The sample size is small to conclude lag screws are better than mini plates but the result of our study provides a basis for further studies done to conclude that the application of LAG SCREW is an effective, inexpensive, quick treatment modality to accelerate healing of fresh, displaced mandibular anterior fracture.  相似文献   
74.

Purpose

To evaluate the safety and efficacy of prostate artery embolization (PAE) for the treatment of benign prostatic hyperplasia for prostates ≥ 80 mL.

Patients and Methods

A retrospective review was conducted of 93 patients with prostate volumes (PVs) ≥ 80 mL treated with PAE from April 2014 through October 2017. Mean patient age was 68.5 years (range 52–88) and mean age-adjusted Charlson comorbidity index was 3.2 (range 1–8). Exclusion criteria included history of biopsy-proven prostate cancer or catheter dependency. Clinical and urodynamic outcomes were reviewed at 1, 3, 6, and 12 months. Adverse events were graded according to the Clavien-Dindo classification.

Results

Mean PV decreased significantly from 141.7 mL to 98.1 mL at 3 months (P < .01) and 82.2 mL at 12 months (P < .01). Significant improvements were seen in 3- and 12-month mean International Prostate Symptom Scores (IPSS) (22.3 vs 7.1 and 7.3, respectively; P < .01 for both), quality of life (QOL) (4.4 vs 1.2 and 1.3; P < .01 for both), and postvoid residual volume (196.7mL vs 92.1 and 61.2 mL; P < .01 and P < .01, respectively). Significant improvement was also seen in 3-month mean maximum urinary flow: 7.7 mL/s vs 12.8 mL/s (P < .01). One grade II complication of stroke occurred; all other complications were self-limited and grade I.

Conclusions

PAE achieved a clinically and statistically significant improvement in symptom burden and secondary outcome measures in patients with PVs ≥ 80 mL. PAE may be an alternate treatment for patients for whom conventional surgical options are limited or associated with significant morbidity.  相似文献   
75.
Purpose: One of the most important implications of ‘Radiation Biology’ research is to improve cancer radiotherapy with minimum side effects. In this regard, combination of chemotherapy with radiation has significantly improved tumor control as well as overall survival in a variety of cancers. However, this has been achieved at the cost of significant normal tissue toxicity, due to the lack of specificity of chemotherapy. Membrane-localized receptor tyrosine kinases (RTKs) have been found to play a driving role in various hallmarks of cancer. Moreover, an early successful clinical trial using RTK-antagonist (cetuximab) to improve tumor radiosensitivity has led to an advancement in this field of research. However, a comprehensive review integrating these findings of various oncogenic RTKs, from basic radiobiology-to-radiotherapy clinical trials, is lacking in literature. Therefore, the present review analyses relevant in-vitro, in-vivo, preclinical/clinical studies and postulates the concept of ‘Radiation Biology of RTKs in Cancer’.

Conclusions: The present review elucidates the effect of IR on various oncogenic RTKs and their mechanisms, downstream signaling, intracellular translocations, their role in the repair of radiation-induced DNA damage and post-irradiation survival. Based on the knowledge derived from RTK biology and the analysis of relevant clinical trials, this review attempts to identify radiobiological considerations, which could be implemented in future trials, combining radiotherapy with RTK-antagonist. Additionally, we identify the radiosensitizing potential of recently developed RTK-targeted nanoformulations. This review would probably change the Radiation Oncologist’s view for translation of tumor-specific radiosensitization in clinic.  相似文献   

76.
Herein is presented a systematic review and meta-analysis of evidence related to operative outcomes associated with robotic-assisted laparoscopic myomectomy (RLM) compared with abdominal myomectomy (AM) and laparoscopic myomectomy (LM). Outcome measures included estimated blood loss (EBL), blood transfusion, operating time, complications, length of hospital stay (LOHS), and costs. Meta-analysis 1 compared RLM vs AM, and meta-analysis 2 compared RLM vs LM. Studies scored moderately well on the Newcastle-Ottawa Quality Assessment Scale. No significant differences were found in age, body mass index, or number, diameter, and weight of myomas. In meta-analysis 1, EBL, blood transfusion, and LOHS were significantly lower; risk of complications was similar; and operating time and costs were significantly higher with RLM. In meta-analysis 2, no significant differences were noted in EBL, operating time, complications, and LOHS with RLM; however, blood transfusion risk and costs were higher. It was concluded that insofar as operative outcomes, RLM has significant short-term benefits compared with AM and no benefits compared with LM. Long-term benefits such as recurrence, fertility, and obstetric outcomes remain uncertain.  相似文献   
77.
Dentigerous cysts are one of the common cysts of the jaws and are associated with the crowns of permanent teeth, most frequently with impacted mandibular third molars. Bilateral dentigerous cysts generally occur in association with a developmental syndrome or systemic diseases. Bilateral dentigerous cysts in absence of a syndrome is a rare condition. There are only 18 cases reported in the literature till date (Dinkar et al. J Indian Soc Pedod Prev Dent 25:56–59, 2007). There are no cases reported with multiple dentigerous cyst involving all the four quadrants.  相似文献   
78.
To better understand the diagnostic and predictive performance of urinary biomarkers of kidney injury, we evaluated γ-glutamyltranspeptidase (GGT), alkaline phosphatase (AP), neutrophil-gelatinase-associated lipocalin (NGAL), cystatin C (CysC), kidney injury molecule-1 (KIM-1), and interleukin-18 (IL-18) in a prospective observational study of 529 patients in 2 general intensive care units (ICUs). Comparisons were made using the area under the receiver operator characteristic curve (AUC) for diagnosis or prediction of acute kidney injury (AKI), dialysis, or death, and reassessed after patient stratification by baseline renal function (estimated glomerular filtration rate, eGFR) and time after renal insult. On ICU entry, no biomarker had an AUC above 0.7 in the diagnosis or prediction of AKI. Several biomarkers (NGAL, CysC, and IL-18) predicted dialysis (AUC over 0.7), and all except KIM-1 predicted death at 7 days (AUC between 0.61 and 0.69). Performance was improved by stratification for eGFR or time or both. With eGFR <60?ml/min, CysC and KIM-1 had AUCs of 0.69 and 0.73, respectively, within 6?h of injury, and between 12 and 36?h, CysC (0.88), NGAL (0.85), and IL-18 (0.94) had utility. With eGFR >60?ml/min, GGT (0.73), CysC (0.68), and NGAL (0.68) had the highest AUCs within 6?h of injury, and between 6 and 12?h, all AUCs except AP were between 0.68 and 0.78. Beyond 12?h, NGAL (0.71) and KIM-1 (0.66) performed best. Thus, the duration of injury and baseline renal function should be considered in evaluating biomarker performance to diagnose AKI.  相似文献   
79.
80.
An 11‐year‐old boy presented with complaints of multiple skin‐colored hard lumps on the right side of his body and progressive deformity of the right leg of 7‐years duration. His parents had also noticed multiple asymptomatic pits over his right arm, palms, and soles since childhood. Examination revealed skin‐colored nontender nodules on the right half of his body and shortening of his right leg. The multiple hyperpigmented pits over the right arm, palm, and sole raised diagnostic difficulties, but histopathologic, radiologic, and biochemical investigations confirmed the features of idiopathic calcinosis cutis and porokeratotic eccrine ostial and dermal duct nevus. Unilateral idiopathic calcinosis cutis has not been previously reported in the literature, and the association with ipsilateral porokeratotic eccrine ostial and dermal duct nevus makes this case unique. Diagnostic difficulties and limited options for treatment make this case interesting academically.  相似文献   
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