Hybrid myocardial revascularization

Background

In patients with advanced coronary artery disease (CAD), coronary artery bypass grafting (CABG) is associated with improved long-term outcomes while percutaneous coronary intervention (PCI) is associated with lower periprocedural complications. A new approach has emerged in the last decade that attempts to reap the benefits of bypass surgery and stenting while minimizing the shortcomings of each approach, hybrid myocardial revascularization (HMR).Three strategies for timing of the hybrid revascularization exists, each with their own inherent advantages and shortcomings: (1) CABG followed by PCI, (2) PCI followed by CABG, or (3) simultaneous CABG + PCI in a hybrid suite.

Studies

The results of the first randomized control trial comparing HMR (CABG first) and standard CABG, POL-MIDES (Prospective Randomized PilOt Study EvaLuating the Safety and Efficacy of Hybrid Revascularization in MultIvessel Coronary Artery DisEaSe), show HMR was feasible for 93.9% of patients whereas conversion to standard CABG was required for 6.1%. At 1 year, both groups had similar all-cause mortality (CABG 2.9% vs. HMR 2%) and major adverse clinical event (MACE)-free survival rates (CABG 92.2% vs. HMR 89.8%). Results of observational and comparative studies show that minimally invasive HMR procedures in patients with multivessel CAD carry minimal perioperative mortality risk and low morbidity and do not increase the risk of postoperative bleeding. The advantage they offer in comparison to classical surgical revascularization is indeed faster rehabilitation and patient’s return to normal life.

Conclusion

Hybrid myocardial revascularization has been developed as a promising technique for the treatment of high-risk patients with CAD. Hybrid revascularization using minimally invasive surgical techniques combined with PCI offers to a part of patients an advantage of optimal revascularization of the most important artery of the heart, together with adequate myocardial revascularization in a relatively delicate way. Indeed, to patients with high operative risk of standard surgery, it offers an alternative which should be considered carefully.

     

High-dose-rate interstitial brachytherapy in recurrent and previously irradiated head and neck cancers--preliminary results

PURPOSE: Although high-dose-rate brachytherapy (HDRBT) offers significant advantages over low dose rate brachytherapy, there are scant data on improved local control (LC) and treatment-related complications in patients with recurrent head and neck (H&N) cancers. We report our preliminary results in patients with recurrent H&N cancers treated with interstitial HDRBT. METHODS AND MATERIALS: Thirty patients with recurrent H&N cancers were treated with HDRBT between September 2003 and October 2005. Seventy-seven percent (23/30) of the patients had either local or regional recurrence in the area of previous external beam radiation therapy. The treatment sites were oral cavity/oropharynx (11/30), neck (10/30), face/nasal cavity (6/30), and parotid bed (3/30). Whereas 18 patients underwent surgical resection followed by HDRBT, 3 patients were treated with combined external beam radiation and HDRBT, and the remaining 9 were treated with HDRBT alone. The dose and fractionation schedules used were 3.4Gy twice per day (b.i.d.) to 34Gy for postoperative cases, 4Gy b.i.d. to 20Gy when combined with 40-50Gy external beam, and 4Gy b.i.d. to 40Gy for definitive treatment. HDRBT was initiated 5 days after catheter placement to allow for tissue healing. RESULTS: With a median followup of 12 months, 6 local recurrences were observed 1-10 months after the procedure. The 2-year LC and overall survival outcomes for the entire group were 71% and 63%, respectively. Patients treated with surgical resection and HDRBT had an improved 2-year LC compared to the patients treated with HDRBT+/-external beam radiation alone (88% vs. 40%, p=0.05). Six Grade II and four Grade III complications were noted in five patients, all observed in the postoperative HDRBT group. CONCLUSION: The preliminary results of HDRBT indicate an acceptable LC and morbidity in recurrent H&N cancers. A planned surgical resection followed by HDRBT is associated with improved tumor control in these high-risk patients. Based on these encouraging results, prospective clinical trials are warranted using HDRBT in recurrent H&N cancers to decrease late toxicity.     

The risk of dementia with increased body mass index

BACKGROUND: identification of modifiable risk factors is crucial in the prevention of dementia, given its limited treatment options. Studies on increased body mass index (BMI) as a risk factor for dementia show conflicting results. METHODS: we systematically retrieved and reviewed longitudinal population-based studies on increased BMI and dementia using a standard protocol. We searched Medline (1966-2006), Ageline (1978-2006), PsychInfo (1966-2006), CINAHL (1982-2006), and other relevant databases, including the reference lists of the eligible articles for review. Included studies were subjected to a quality assessment protocol. RESULTS: we identified eight studies that met our selection criteria. These studies covered 1,688 cases of dementia from 28,697 participants. After adjustment for age, smoking, comorbidities, and other confounders, four studies presented significantly increased risk of dementia with elevated BMI. CONCLUSION: this systematic review supports the hypothesis that increased BMI is independently associated with increased risk of dementia. Long-term studies to examine the mechanisms underlying the relationship between obesity and dementia are needed.     

Histological Aggressiveness of Fluorodeoxyglucose Positron-Emission Tomogram (FDG-PET)-Detected Incidental Thyroid Carcinomas

Background We previously reported a high incidence of primary thyroid cancer in fluorodeoxyglucose positron-emission tomogram (FDG-PET)-detected incidental thyroid abnormalities. The aim of our study was to determine if these FDG-PET-detected thyroid malignancies represent a more-aggressive variant of primary thyroid carcinoma. Materials and methods All patients that underwent operative intervention for FDG-PET-detected incidental thyroid abnormalities were identified (June 2003 to April 2006). Patients with a diagnosis of primary thyroid carcinoma on final histopathology were included in the study. The patient demographics and histopathological findings were analyzed to identify adverse prognostic features. Results In 11,500 patients, 17,250 FDG-PET scans were performed; 377 of these patients (3.2% of patients and 2.1% of FDG-PET scans) had findings positive for thyroid abnormality. Of the 32 patients that underwent operative intervention, 22 patients with a final diagnosis of primary thyroid malignancy were included in the study. A greater number of patients [12 patients, (54%)] were noted to harbor poor prognostic variants of primary thyroid carcinoma on final histopathology [tall-cell variant: 11 patients (50%) and poorly differentiated thyroid carcinoma: 1 patient (4%)]. Extra-thyroidal extension (ETE) was noted in the majority of patients [14 patients (63%)]. In patients with tall cell variant on final histopathology, the rate of ETE was even higher [10 patients (90%)]. Conclusion Thyroid malignancies incidentally detected on FDG-PET scan harbor a high rate of unfavorable prognostic features and may represent a more-aggressive variant of primary thyroid carcinoma. These patients need to be subjected to further investigation with a view to possible operative intervention.     

LOXL1 and LOXL4 are epigenetically silenced and can inhibit ras/extracellular signal-regulated kinase signaling pathway in human bladder cancer

Promoter hypermethylation is one of the common mechanisms leading to gene silencing in various human cancers. Using a combination of pharmacologic unmasking and microarray techniques, we identified 59 candidate hypermethylated genes, including LOXL1, a lysyl oxidase-like gene, in human bladder cancer cells. We further showed that LOXL1 and LOXL4 are commonly silenced genes in human bladder cancer cells, and this silence is predominantly related to promoter methylation. We also found LOXL1 and LOXL4 gene methylation and loss of expression in primary bladder tumors. In addition, somatic mutations were identified in LOXL4, but not in LOXL1 in bladder cancer. Moreover, reintroduction of LOXL1 and LOXL4 genes into human bladder cancer cells leads to a decrease of colony formation ability. Further studies indicated that the overexpression of LOXL1 and LOXL4 could antagonize Ras in activating the extracellular signal-regulated kinase (ERK) signaling pathway. Thus, our current study suggests for the first time that lysyl oxidase-like genes can act as tumor suppressor genes and exert their functions through the inhibition of the Ras/ERK signaling pathway in human bladder cancer.     

Changing sagittal plane body position during single-leg landings influences the risk of non-contact anterior cruciate ligament injury

Purpose

To examine the effects of different sagittal plane body positions during single-leg landings on biomechanics and muscle activation parameters associated with risk for anterior cruciate ligament (ACL) injury.

Methods

Twenty participants performed single-leg drop landings onto a force plate using the following landing styles: self-selected, leaning forward (LFL) and upright (URL). Lower extremity and trunk 3D biomechanics and lower extremity muscle activities were recorded using motion analysis and surface electromyography, respectively. Differences in landing styles were examined using 2-way Repeated-measures ANOVAs (sex × landing conditions) followed by Bonferroni pairwise comparisons.

Results

Participants demonstrated greater peak vertical ground reaction force, greater peak knee extensor moment, lesser plantar flexion, lesser or no hip extensor moments, and lesser medial and lateral gastrocnemius and lateral quadriceps muscle activations during URL than during LFL. These modifications of lower extremity biomechanics across landing conditions were similar between men and women.

Conclusions

Leaning forward while landing appears to protect the ACL by increasing the shock absorption capacity and knee flexion angles and decreasing anterior shear force due to the knee joint compression force and quadriceps muscle activation. Conversely, landing upright appears to be ACL harmful by increasing the post-impact force of landing and quadriceps muscle activity while decreasing knee flexion angles, all of which lead to a greater tibial anterior shear force and ACL loading. ACL injury prevention programmes should include exercise regimens to improve sagittal plane body position control during landing motions.