Does long-distance running cause osteoarthritis?

There is a dose-response relationship between physical activity and the reduced risk of some diseases (eg, cardiovascular disease, diabetes mellitus). At a certain "dose," however, the reduced risk of some diseases may be offset by an increased risk of injury and osteoarthritis. Osteoarthritis can be caused by trauma to, or overuse of, the joints. Sports injuries often occur as a result of dysfunctions in balance or the musculoskeletal system operating in nonneutral mechanics. It is unclear if long-distance running causes the knee and hip joints to deteriorate. The results of animal studies reveal a pattern of increased incidence of arthritis in these joints when there is a history of injury or use in atypical environments (eg, laboratory settings). Human studies show an increase in radiographic evidence of osteoarthritis in endurance sports athletes, but no related increase in symptoms reported. Although there are not currently enough data to give clear recommendations to long-distance runners, it appears that long-distance running does not increase the risk of osteoarthritis of the knees and hips for healthy people who have no other counterindications for this kind of physical activity. Long-distance running might even have a protective effect against joint degeneration. The authors recommend further study.     

Does methylene blue protect the kidney tissues from damage induced by ciclosporin A treatment?

Ciclosporin A (CsA) is the first-choice immunosuppressant universally used in allotransplantation and autoimmune diseases. However, it has been demonstrated that this drug produces negative side effects in several organs and in particular in the lymphoid organs and in the kidney. It has been suggested that the CsA causes deleterious effects because it increases the oxygen free radical production. Here we wanted to test whether antioxidants protect the kidney parenchyma from the toxicity induced by CsA. We used methylene blue (MB), because it inhibits the formation of oxygen free radicals. The study was carried out in four groups of Wistar rats. Group I animals were intraperitoneally injected with MB (1 mg/kg/day) for 21 days; group II animals were subcutaneously injected with CsA (15 mg/kg/day) for 21 days; group III animals were treated with CsA combined with MB at the same doses and for the same periods as groups I and II, and group IV animals were injected subcutaneously with olive oil for 21 days as controls. The kidneys and the thymuses were subsequently removed and examined by conventional morphological staining (hematoxylin-eosin and Masson's trichrome) and enzymatic (NADPH-diaphorase, cytochrome, c oxidase, and superoxide anion production) and immunoenzymatic (inducible nitric oxide synthase--iNOS, endothelial nitric oxide synthase--eNOS) techniques. The thymuses were used to check the persistence of CsA-immunosuppressive effects during MB administration. Group I, III, and IV animals showed a normal kidney architecture and low levels of NADPH-diaphorase and of superoxide anion in all structures studied (proximal and distal tubules, glomeruli and the Henle loops). The cytochrome c oxidase showed a strong activity in proximal tubules, a moderate activity in distal tubules, and a weak activity in glomeruli and in the Henle loops. The expression of iNOS was weak in the proximal tubular epithelial cells and negative in the glomeruli, while eNOS was found to be moderately positive in the glomeruli and in the interstitial arteries, but not in the tubules and in the Henle loops. Degenerative changes with tubulointerstitial injury in the cortex of CsA-treated kidneys (group II) and increases of NADPH-diaphorase levels, iNOS activity, and superoxide staining were found in all structures. The expression of eNOS did not change in group I, III and IV animals. MB combined with CsA prevented the degenerative changes caused by CsA, preserving the structural, enzymatic, and immunoenzymatic integrity of the renal parenchyma. The mechanism by which MB exerts its protective action is not yet clear, but it seems to be due to its ability to inhibit xanthine oxidase and to quench nitric oxide production. Moreover, these data have been also supported by the following: (1) the superoxide anion levels were very high after CsA treatment and reduced after CsA-MB treatment, and (2) the iNOS levels increased in CsA-treated rats and showed normal levels after CsA-MB treatment. Moreover we demonstrated that MB administration did no compromise the CsA immunosuppressive effects, since the thymus showed a cytoarchitecture like that observed in CsA-treated rats.     

Does pregnancy protect against intrathecal lidocaine-induced transient neurologic symptoms?

We investigated the incidence of transient neurologic symptoms (TNS) after the use of hyperbaric lidocaine as compared with hyperbaric bupivacaine in patients undergoing cesarean delivery under spinal anesthesia. Two hundred women scheduled for cesarean delivery were randomly allocated to receive spinal anesthesia with 75 mg hyperbaric lidocaine 5% (n = 100) or 12 mg hyperbaric bupivacaine 0.75% (n = 100). Spinal anesthesia was administered to all patients in the sitting position with a 25-gauge Whitacre needle. The level of sensory blockade, time to full recovery, and intraoperative hemodynamic profile were noted in all patients. The patients were interviewed postoperatively for three consecutive days to detect the occurrence of TNS. The incidence of TNS was zero (95% confidence interval 0%--3%) in both the Lidocaine and the Bupivacaine Groups. Our results indicate that the frequency of postoperative TNS does not exceed 3% in patients undergoing cesarean delivery at term using hyperbaric lidocaine 5% or hyperbaric bupivacaine 0.75%.     

Does low peritoneal glucose load protect from the development of left ventricular hypertrophy in peritoneal dialysis patients?

Background

Left ventricular hypertrophy (LVH) is a major predictor of the development of cardiovascular events that is considered the main cause of morbidity and mortality in peritoneal dialysis (PD) patients. This study aimed to evaluate retrospectively the impact of low peritoneal glucose load on left ventricular mass (LVM) in PD patients.

Methods

36 patients who were on continuous ambulatory PD for at least a period of 2 years enrolled in the study. Of them, 23 patients received only glucose-based solutions (GBS) [high peritoneal glucose load group (HPGL group)] from the start of PD, and 13 patients received AAS in combination with GBS when their serum albumin decreased to levels <3.5 g/dl [low peritoneal glucose load group (LPGL group)]. AAS was substituted with 1.36 % GBS when serum albumin rose to ≥3.5 g/dl and restarted when serum albumin fell to <3.5 g/dl. Medical history, physical findings, echocardiographic, laboratory and hydration status data from the first month of PD and after 24 months, were obtained from each patient’s medical records.

Results

Mean LVM index (LVMI) increased in both groups (p ≤ 0.010). The increment in mean LVMI was higher in HPGL group compared to LPGL group (p = 0.006). At 24 months: peritoneal glucose load index (PGLI), fluid overload, mean arterial pressure (MAP), HbA1c and hsCRP were higher in HPGL group (p ≤ 0.010), while 24 h ultrafiltration, weekly Kt/V, serum albumin levels and RRF were higher in LPGL group (p ≤ 0.025). The increment (Δ between the values of each parameter from the start of PD and after 24 months) in PGLI, fluid overload, MAP, HbA1c and hsCRP values were higher in HPGL group (p < 0.001).

Conclusions

Low peritoneal glucose load may be associated with a protective effect from the development of LVH in PD patients.

     

Is the incidence of elbow osteoarthritis underestimated? Insights from paleopathology

OBJECTIVES: Osteoarthritis is uncommon at the elbow in contemporary populations. We sought to determine whether this was also the case in medieval and premodern times. MATERIAL AND METHODS: Standard criteria for osteoarthritis were applied to 496 complete elbows from a necropolis in Provence, France. RESULTS: Osteoarthritis was found in 27% of elbows. Significant differences were noted across periods and age groups but not between the right and left sides. CONCLUSION: Our data suggest that the symptoms of elbow osteoarthritis may be far milder than expected from the underlying pathological lesions. The incidence of elbow osteoarthritis in contemporary populations is probably underestimated. The high prevalence of elbow osteoarthritis in archeological populations cannot be taken as a marker for activities placing stress on the upper limbs.     

Does antegrade cerebral perfusion protect the brain during deep hypothermic circulatory arrest?

Purpose

This study compares cerebral protection using no cerebroplegia and using antegrade cerebroplegia with variable flow rates during deep hypothermic circulatory arrest (DHCA).

Methods

Twenty healthy neonatal piglets (2.5-3.8 kg) underwent 60 minutes of DHCA. No cerebroplegia was used in group 1 (n = 5). Cold (16°C) antegrade cerebral perfusate was administered through the innominate artery at 10 mL/kg per minute in group 2 (n = 5), at 25 mL/kg per minute in group 3 (n = 5), and at 50 mL/kg per minute in group 4 (n = 5). Venous samples for lactate, pyruvate, S-100B protein, and creatine kinase BB (CKBB) were drawn from the jugular vein before and after discontinuation of cardiopulmonary bypass—lactate at 5 minutes postbypass, pyruvate at 5 minutes postbypass, S-100B protein at 30 minutes postbypass, and CKBB at 6 hours postbypass. Piglets were killed 6 hours postbypass and their brains were harvested for histological/immunologic studies. Extent of damage was assessed using a semiquantitative score of 0 to 4 based on a validated method.

Results

Evidence for significant apoptosis and necrosis was apparent in all groups. The mean H&E score was 2.2 for group 1, 2.3 for group 2, 2.5 for group 3, and 2.3 for group 4. The mean terminal deoxynucleotidyl transferase-mediated dUTP-biotin nick end labeling score was 1.0 for group 1, 1.2 for group 2, 1.7 for group 3, and 0.8 for group 4. Pathological changes were not greater in the piglets that did not have antegrade cerebral perfusion. Serum lactate, pyruvate, S-100B protein, and CKBB did not distinguish between perfusion strategies.

Conclusions

In neonates, unmodified antegrade cerebral perfusion at flow rates of 10, 25, and 50 mL/kg per minute during DHCA does not provide additional protection of the brain as determined by histology, immunology, serum lactate, pyruvate, S-100B protein, and CKBB.     

Does Body Armor Protect from Firearm Injuries?

BACKGROUND: Bullet-proof vests and helmets protect from harm in combat and military engagements. The use of armor against shrapnel has been studied, yet little has been documented as to how they protect from high velocity gunshots. This study aims to describe the medical consequences of high velocity firearm injuries and to differentiate between patients injured while using protective wear and those injured unprotected. STUDY DESIGN: National trauma registry data on injury characteristics, treatment and outcomes between October 1, 2000 and December 31, 2003 were retrieved and analyzed. RESULTS: There were 669 terror-related firearm injuries recorded: 236 (37.8%) in soldiers (protected) and 433 (62.2%) in civilians (unprotected). Injury severity was notably higher in civilian patients (31% versus 16% with Injury Severity Score>or=16). Civilians had more ICU care (26% versus 20%, p=0.06), and double the inpatient mortality (8.6% [n=37] versus 3.4% [n=8] patients). Protected body regions such as abdomen, chest, and brain, were injured less frequently. Once a traumatic brain injury was sustained, no statistical differences were found in severity distribution, ICU stay, or inpatient death between protected and unprotected patients. But injury severity in patients with chest injuries was much higher in those who were unprotected (Injury Severity Score>or=25, 41% versus 23%, respectively, p=0.08). This increased severity could be attributed partly to more multiple injuries involving the chest. Abdominal injuries showed a similar pattern. CONCLUSIONS: Body armor has a protective effect on victims of high velocity gunshot wounds; lower rates of head, brain, chest, and abdominal injuries are seen. In addition, armor reduces the severity of injuries to the chest and the abdomen.     

Does warm antegrade intermittent blood cardioplegia really protect the heart during coronary surgery?

OBJECTIVE: Intermittent antegrade blood cardioplegia (IABC) has been standardized as a routine technique for myocardial protection in coronary surgery. However, if the myocardium is known to tolerate short periods of ischemia during hypothermic arrest, it may be less tolerant of warm ischemia, so the optimal cardioplegic temperature of intermittent antegrade blood cardioplegia is still controversial. The aim of this study was to compare the effects of warm intermittent antegrade blood cardioplegia and cold intermittent antegrade blood cardioplegia on myocardial pH and different parameters of the myocardial metabolism. METHODS: Thirty patients undergoing first-time isolated coronary surgery were randomly allocated into two groups: group 1 (15 patients) received warm (37 degrees C) intermittent antegrade blood cardioplegia and group 2 (15 patients) received cold (4 degrees C) intermittent antegrade blood cardioplegia. The two randomization groups had similar demographic and angiographic characteristics. Total duration of cardiopulmonary bypass (108+/-17 and 98+/-21 min) and of aortic cross-clamping (70+/-13 and 65+/-15 min) were similar. The cardioplegic solutions were prepared by mixing blood with potassium and infused at a flow rate of 250 ml/min for a concentration of 20 mEq/l during 2 min after each anastomosis or after 15 min of ischemia. Intramyocardial pH was continuously measured during cardioplegic arrest by a miniature glass electrode and values were corrected by temperature. Myocardial metabolism was assessed before aortic clamping (pre-XCL), 1 min after removal of the clamp (XCL off) and 15 min after reperfusion (Rep) by collecting coronary sinus blood samples. All samples were analyzed for lactate, creatine kinase (MB fraction), myoglobin and troponin I. Creatine kinase and troponin I were also daily evaluated in peripheral blood during 6 days post-operatively. RESULTs: The clinical outcomes and the haemodynamic parameters between the two groups were identical. In group 1, XCL off and Rep were associated with higher coronary sinus release of lactate (5.5 +/- 1.8 and 2.2 +/- 0.5 mmol/l) than in group 2 (2.0 +/- 0.7 and 1.6 +/- 0.3 mmol/l, P < 0.05). Mean intramyocardial pH was lower in group 1 (7.23 +/- 0.08) than in group 2 (7.65 +/- 0.30, P < 0.05). There were no significant differences between the two groups with respect of creatine kinase (MB fraction) either after Rep or during the post-operative period. Lower coronary sinus release of myoglobin was detected at Rep in group 1 (170 +/- 53 microg/l) than in group 2 (240 +/- 95 microg/l, P < 0.05). At day 1, a lower release of troponin I was found in group 1 (0.11 +/- 0.07 g/ml) compared to group 2 (0.17 +/- 0.07 ng/ml, P < 0.05). CONCLUSION: With regards to similar clinical and haemodynamic results, myocardial protection induced by warm IAEX is associated with more acidic conditions (intramyocardial pH and lactate release) and less myocardial injury (myoglobin and troponin I release) than cold intermittent antegrade blood cardioplegia during coronary surgery.     

Self-management for osteoarthritis of the knee: Does mode of delivery influence outcome?

Background  

Self-management has become increasingly popular in the management of chronic diseases. There are many different self-management models. Meta analyses of arthritis self-management have concluded that it is difficult to recommend any one program in preference to another due to inconsistencies in the study designs used to evaluate different programs.