Expression of modulators of extracellular matrix structure after anterior cruciate ligament injury

The ability of the anterior cruciate ligament (ACL) to heal after injury declines within the first 2 weeks after ACL rupture. To begin to explore the mechanism behind this finding, we quantified the expression of genes for collagen I and III, decorin, tenascin‐C, and alpha smooth muscle actin, as well as matrix metalloproteinase (MMP)‐1 and ‐13 gene expression within multiple tissues of the knee joint after ACL injury in a large animal model over a 2‐week postinjury period. Gene expression of collagen I and III, decorin, and MMP‐1 was highest in the synovium, whereas the highest MMP‐13 gene expression levels were found in the ACL. The gene expression for collagen and decorin increased over the 2 weeks to levels approaching that in the ligament and synovium; however, no significant increase in either of the MMPs was found in the provisional scaffold. This suggests that although the ACL and synovium up‐regulate both anabolic and catabolic factors, the provisional scaffold is primarily anabolic in function. The relative lack of provisional scaffold formation within the joint environment may thus be one of the key reasons for ACL degradation after injury.     

Establishing a central zone in scaphoid surgery: a computational approach

Purpose

Scaphoid fractures are commonly fixed with headless cannulated screws positioned centrally in the scaphoid. Judgement of central placement of the screw may be difficult. We generated a central zone using computer analysis of 3D reconstructions of computed tomography (CT) images. As long as the screw axis is completely contained within this central zone, the screw would be considered as centrally placed.

Methods

Thirty cases of 3D CT reconstructions of normal scaphoids in a computerised operation planning and simulation system (Vxwork software) were obtained. The central zone was established after some distance shrinkage of the original scaphoid surface reconstruction model using the function “erode” in the software. The shape of the central zone was evaluated, and the width of the central zone in the proximal pole, waist portion and distal pole was measured. We also established the long axis of the scaphoid to see whether it stays in the central zone.

Results

All central zones could be divided into distal, waist and proximal portions according to the corresponding irregular shape of the scaphoid. As the geometry of the central zone was so irregular and its width very narrow, it was possible to completely contain the screw axis either in the proximal portion alone, waist alone or distal central zone alone.

Conclusions

Establishing the central zone of scaphoid 3D CT images provided a baseline for discussion of central placement of a scaphoid screw. The geometry of the scaphoid central zone determined that the screw could hardly be inserted through entire scaphoid central area during surgery.     

New look at nutritional care for obese patient candidates for bariatric surgery

BackgroundThe combination of preoperative deficiencies and the restrictions and malabsorption possibly induced by bariatric surgery could lead patients to experience important nutritional deficits during the late postoperative period. Our objective was to characterize the eating, anthropometric, and biochemical profiles of obese candidates for bariatric surgery at a bariatric surgery center of a university hospital.MethodsA retrospective study with the analysis of medical records of candidates for bariatric surgery from 2007 to 2008 was performed. A total of 80 adult patients, aged 45 ± 11 years, were included in the present study.ResultsThe mean patient weight was 145 ± 24 kg, and the mean body mass index was 54 ± 8 kg/m². Of the 80 patients, 78% had ≥1 co-morbidities related to obesity. The reported daily energy intake before surgery was 1981 ± 882 kcal, with 48% ± 11% consisting of carbohydrate, 29% ± 8% of lipids, and 23% ± 8% of protein. The mean number of daily meals was 4 ± 1. Patients with a greater body mass index ingested a smaller amount of calories per kilogram of current weight. The occurrence of hyperglycemia, hyperuricemia, and dyslipidemia and of nutritional deficiencies, among them magnesium (19%), vitamin A (15%), vitamin C (16%), iron (9%), β-carotene (3%), and vitamin B₁₂ (3%), was high.ConclusionThe high occurrence of micronutrient deficiency detected by biochemical analysis in morbidly obese candidates for bariatric surgery, representing a disabsorptive process, might involve a poorer prognosis during the late postoperative period. A preoperative evaluation of the nutritional parameters and the food intake pattern is recommended for these patients, together with the necessary interventions.     

Cardiorespiratory response to exercise in Ebstein's anomaly

Fourteen patients with unrepaired Ebstein's anomaly underwent maximal exercise testing between October 1982 and April 1984. Compared with control subjects, these patients had significantly lower values for total work performed, exercise time, maximal oxygen uptake, blood oxygen saturation at rest and during exercise, and heart rate and systolic blood pressure during maximal exercise. They had a significant increase in heart rate at rest. The ventilatory equivalent for oxygen was increased significantly both at rest and during exercise. Thus, patients with Ebstein's anomaly have decreased exercise tolerance owing to both cardiac and respiratory limitations.     

A microcirculatory technique for evaluating intravascular and topical administration of vasoactive agents: Response to AVP in the SHR

A "closed bath" cremaster muscle preparation is described which permits the administration of vasoactive materials to the microvasculature via intraarterial injection and topical suffusion. The technique is evaluated in spontaneously hypertensive (SHR) and Wistar-Kyoto (WKY) rats by comparing arteriolar responses to intraarterial and topically suffused arginine vasopressin. The preparation utilizes a thermostatically heated brass suffusion chamber overlying the cremaster. The chamber is closed with a glass coverslip. Experimental materials are presented to the microvessels via intraarterial injection or suffusion through the chamber. The coverglass permits high optical resolution with both routes of administration. Following vasopressin administration, changes in arteriolar diameter were continuously monitored by image-shearing techniques or variable-resistance calipers. The responses were analyzed by comparing both the peak 5-sec vasoconstriction and a 60-sec integrated response. Intraarterial and topical suffusion of vasopressin (1.25 X 10(-10)-3.75 X 10(-7) M) caused dose-dependent vasoconstriction among 23-microns arterioles. Compared to the WKY, vasoconstriction was greater in the SHR when vasopressin was administered intraarterially. A similar strain difference was not observed with topical suffusion. The dose-response curves with intraarterial vasopressin were shifted approximately 100-fold in concentration to the right relative to those with topically suffused vasopressin. The "closed bath" cremaster muscle preparation described has several distinct advantages: (1) it permits introduction of different vasoactive materials in the most physiological manner in the same animal, and (2) it maintains high optical resolution and clarity for critical observation of the smallest vessels, even with suffusion.     

Contrast-Enhanced Spectral Mammography and tumor size assessment: a valuable tool for appropriate surgical management of breast lesions

Purpose

To compare the accuracy of Contrast-Enhanced Spectral Mammography (CESM), MG, US, and breast MRI in estimating the size of breast lesions requiring surgery. The postoperative histology size of the lesion was used as the gold standard.

Material and methods

Two hundred thirty-three non-benign lesions in 189 patients were included in the analyses. All the selected patients underwent CESM and at least one other conventional diagnostic exam (US, MG, or MRI). Subsequently, all the patients underwent surgery preceded by cytological/histological examination. The largest diameter of the lesion at imaging was measured by a radiologist with more than 10 years’ experience and then compared with the size of the lesion in the histological sample at the surgery (gold standard).

Results

Among the 233 breast lesions, 196 were evaluated with US, 206 with MG and 160 with MRI. We found no statistically significant differences between size measurements using CESM and MRI compared with the measurements at the surgery (p value 0.63 and 0.51), whereas a significant difference was found for MG and US (p?<?0.001).

Conclusion

CESM is a reliable method for estimating the size of breast lesions: its performance seems superior to US and MG and comparable to MRI.

     

Muscle strength and soccer practice as major determinants of bone mineral density in adolescents

ObjectivesTo analyse the relationship between isokinetic strength of the lower limb muscles and bone mineral density and content (BMD, BMC) of adolescent male soccer players and age-matched controls not involved in sport (12–15 years).MethodsA random sample of 151 young males was divided into soccer players (SG; n = 117) and control subjects (CG; n = 34). Peak torque of knee extensors (PTE) and flexors (PTF) was measured during isokinetic knee joint movement (90°/s) of the dominant and non-dominant lower limbs. BMD and BMC of the whole-body, lumbar spine, dominant/non-dominant lower limb were determined by dual-energy X-ray absorptiometry. Physical activity was monitored with accelerometers during 5 days. Estimated maturity offset was used as an indicator of biological maturity status.ResultsWhole-body BMD (1.03 ± 0.01 vs. 0.98 ± 0.01 g/cm², P = 0.003) and dominant (1.09 ± 0.01 vs. 1.02 ± 0.01 g/cm², P < 0.001) and non-dominant (1.09 ± 0.01 vs. 1.01 ± 0.01 g/cm², P < 0.001) lower limb BMD was greater in SG compared to CG. No significant differences were found for BMC. Compared to CG, SG performed better in the YY-IE2 test (780 ± 40 vs. 625 ± 31 m), exhibited higher PTE (dominant limb: 155.2 ± 30.3 vs. 123.4 ± 37.0 N m; non-dominant limb: 156.2 ± 36.1 vs. 120.4 ± 41.1 N m) and PTF muscles (dominant limb: 79.0 ± 25.3 vs. 57.1 ± 25.3 Nm; non-dominant limb: 73.3 ± 20.7 vs. 57.0 ± 24.2 N m). Moreover, the PTE, soccer participation and maturity status were positively associated with the BMD at all body sites (r² = 0.57–0.73, P < 0.05).ConclusionsMuscle strength of knee extensors is associated with BMD and BMC at all body sites. Muscle-skeletal structures respond positively to the weight-bearing and impact-loading imposed by soccer practice. Soccer seemed to be a multilateral balanced sport activity.     

Robot-Assisted Transaxillary Thyroid Surgery in the United States: Is it Comparable to Open Thyroid Lobectomy?

Background  

The purpose of this study was to compare the outcome of robot-assisted transaxillary thyroid surgery (RATS) to the standard open technique for thyroid lobectomy in the U.S. population.     

Evaluating chronic venous disease with a new venous severity scoring system

BACKGROUND: The Venous Clinical Severity Score (VCSS) has been proposed by the American Venous Forum as an objective means to clinically assess venous disease more completely than with the clinical CEAP classification. However, validation of the VCSS against an objective test is lacking. The purpose of this study was to test the VCSS against abnormalities found on venous ultrasound (US) scans. METHODS: As part of a screening project in a large kindred population with protein C deficiency, VCSS and venous US scanning were performed in 210 patients (420 limbs). A single examiner scored the VCSS (0-3) clinically for pain, varicose veins, edema, skin pigmentation, inflammation, induration, ulcer duration and size, and compressive therapy. Another experienced examiner, blinded to the subject's medical history, performed a US examination of the deep and superficial venous system, with a hand-carried US system. The relationship between US and VCSS scores was analyzed by calculating an odds ratio (OR) and its 95% confidence interval (CI). RESULTS: Of the 420 limbs screened, VCSS was 0 in 283 limbs, and VCSS was 1 or greater in the following categories: pain, 63 limbs; varicose veins, 70 limbs; edema, 51 limbs; skin pigmentation, 17 limbs; inflammation, 2 limbs; induration, 8 limbs; and compressive therapy, 9 limbs. The highest total score in any limb was 8. A clear association was seen with the VCSS and abnormalities found on US scans. When the score was dichotomized (0 = normal, 1 = any abnormality), it was a strong predictor of US scan abnormalities; limbs with VCSS greater than 0 had a 26-fold greater chance of US scan abnormalities than did limbs with VCSS = 0 (OR, 26.5; 95% CI, 11-64). With ultrasonography as the standard, sensitivity of VCSS compared with US scans was 89.3%, and specificity was 76.1%. Negative predictive value of VCSS = 0 was 97.9%, and positive predictive value for any positive score was 36.5% CONCLUSIONS: The results of this study are based on a large kindred population with a higher risk for venous disease than found in the general population. Though the VCSS was devised to quantify the severity of chronic venous disease, this study found it a useful screening tool. The VCSS showed good association with abnormalities on US scans, and when VCSS = 0 there is a high likelihood that the patient does not have venous disease. This simple test may prove valuable in clinical practice.     

Replacement of the aortic valve in patients under 50 years of age: long-term follow-up of the St. Jude Medical prosthesis

BACKGROUND: Aortic valve replacement in the young adult (aged 18 to 50 years) is a choice between a mechanical prosthesis with attendant lifelong anticoagulation or biological prostheses of varying types that may have limited life expectancy in this age group. METHODS: The Cardiac Surgical Research Foundation database was accessed to determine long-term outcomes in patients having aortic valve replacement with the St. Jude Medical Valve. This database has been privately maintained since the world's first St. Jude Medical (SJM) valve implant in 1977. Patients were contacted by questionnaire or by telephone if the survey was not returned. Follow-up was 93% complete. RESULTS: From October 1977 through October 1997, 271 patients less than 50 years of age had isolated aortic valve replacement. Follow-up was 1957 patient years. Thirty-day operative mortality was 1.1% with 18 late deaths, 4 of which were valve related. Ninety percent of survivor INR responses indicated a frequency of monthly INR checks or less. Valve-related events including percent per patient year and mortality related to these events included thromboembolism, 6 episodes (0.3% per patient year, no deaths); anticoagulant-related bleeding, 6 events (0.3% per patient year, 2 deaths); paravalvular leak, 6 events (0.3% per patient year, 2 deaths); valve thrombosis, 2 events (0.1% per patient year, no deaths); and endocarditis, 3 events (0.15% per patient year, no deaths). There was no incidence of structural valve failure. CONCLUSIONS: The SJM valve has a long record of excellent performance with durability lasting more than 20 years. The incidence of untoward events is low and death over time due to valve-related complications is low (4 of 271). The SJM valve has become our valve of choice for younger patients.