Growth of human B cell colonies from peripheral blood of patients with systemic lupus erythematosus.

Human B cell colonies were grown from peripheral blood of 12 patients with systemic lupus erythematosus (SLE) and from 12 healthy control subjects. The SLE group showed a large increase (p less than 0.001) in the number of colony forming cells (CFC) present in peripheral blood as compared with controls. The CFC were of the pre-B cell type. There was also a loss of OKT8+ cell inhibition of B cell colony growth in the SLE group compared with control subjects.     

Biomarkers of Cardiac Stress and Injury in Athletes: What Do They Mean?

Purpose of the Review

Markers of myocardial stress, including troponin, creatine kinase, and brain natriuretic peptide are frequently elevated after endurance athletic pursuits. Here, we summarize the current literature pertaining to the potential mechanism of cardiac enzyme release in athletes and seek to determine the clinical implications of these findings.

Recent Findings

Recent studies have highlighted the potential adverse cardiac effects of long-term extreme endurance exercise. While troponin release occurs in a pattern distinct from ischemic damage, BNP release has been correlated with right ventricular dysfunction and is likely related to wall stress from prolonged increases in cardiac output. Higher intensity pre-race training regimes are associated with lower race-day enzyme release.

Summary

While the holistic benefits of regular moderate exercise are indisputable, recent studies have raised concerns about the potential risks of extreme endurance exercise. Release of serum biomarkers suggesting myocardial damage was first described in the 1970s, yet our understanding of the implications of these findings remains incomplete. The mechanisms of release are complex but appear to be primarily physiological phenomena rather than pathologic.

     

Network Analysis of Internet Addiction Symptoms Among a Clinical Sample of Japanese Adolescents with Autism Spectrum Disorder

Journal of Autism and Developmental Disorders - In the present study, we employed network analysis that conceptualizes internet addiction (IA) as a complex network of mutually influencing symptoms...     

Oxygen Consumption of Elite Distance Runners on an Anti-Gravity Treadmill?

Lower body positive pressure (LBPP), or ‘anti-gravity’ treadmills® have become increasingly popular among elite distance runners. However, to date, few studies have assessed the effect of body weight support (BWS) on the metabolic cost of running among elite runners. This study evaluated how BWS influenced the relationship between velocity and metabolic cost among 6 elite male distance runners. Participants ran three- 16 minute tests consisting of 4 stages of 4 minutes at 8, 7, 6 and 5 min·mile⁻¹ pace (3.35, 3.84, 4.47 and 5.36 m·s⁻¹), while maintaining an aerobic effort (Respiratory Exchange Ratio ≤1.00). One test was run on a regular treadmill, one on an anti-gravity treadmill with 40% BWS and one with 20% BWS being provided. Expired gas data were collected and regression equations used to determine and compare slopes. Significant decreases in oxygen uptake (V̇O₂) were found with each increase in BWS (p < 0.001). At 20% BWS, the average decrease in net VO2 was greater than proportional (34%), while at 40% BWS, the average net reduction in VO₂ was close to proportional (38%). Across velocities, the slope of the relationship between VO₂ and velocity (ΔV̇O₂/Δv) was steeper with less support. The slopes at both the 20% and 40% BWS conditions were similar, especially when compared to the regular treadmill. Variability in VO₂ between athletes was much greater on the LBPP treadmill and was greater with increased levels of BWS. In this study we evaluated the effect of body weight support on V̇O₂ among elite distance runners. We have shown that oxygen uptake decreased with support, but not in direct proportion to that support. Further, because of the high variability in oxygen uptake between athletes on the LBPP treadmill, prediction equations may not be reliable and other indicators (heart rate, perceived exertion or directly measured oxygen uptake) should be used to guide training intensity when training on the LBPP treadmill.

Key points

• With increasing amounts of body weight-support (BWS), the slope of the relationship between velocity and oxygen consumption (ΔVO₂/Δv) decreases significantly. This means the change in oxygen consumption (VO₂) is significantly smaller over a given change in velocity at higher amounts of BWS.
• There is a non-linear decrease in VO₂ with increasing BWS. As such, with each increment in the amount of BWS provided, the reduction in VO₂ becomes increasingly smaller.
• This paper provides first of its kind data on the effects of BWS on the cost of running among highly trained, elite runners. The outcomes of this study are in line with previous findings among non-elite runners.

Key words: AlterG®, anti-gravity treadmill®, distance running, elite, oxygen consumption, LBPP treadmill     

Pancreatic cancer surgery and nutrition management: a review of the current literature

Surgery remains the only curative treatment for pancreaticobiliary tumors. These patients typically present in a malnourished state. Various screening tools have been employed to help with preoperative risk stratification. Examples include the subjective global assessment (SGA), malnutrition universal screening tool (MUST), and nutritional risk index (NRI). Adequate studies have not been performed to determine if perioperative interventions, based on nutrition risk assessment, result in less morbidity and mortality. The routine use of gastric decompression with nasogastric sump tubes may be unnecessary following elective pancreatic resections. Instead, placement should be selective and employed on a case-by-case basis. A wide variety of feeding modalities are available, oral nutrition being the most effective. Artificial nutrition may be provided by temporary nasal tube (nasogastric, nasojejunal, or combined nasogastrojejunal tube) or surgically placed tube [gastrostomy (GT), jejunostomy (JT), gastrojejunostomy tubes (GJT)], and intravenously (parenteral nutrition, PN). The optimal tube for enteral feeding cannot be determined based on current data. Each is associated with a specific set of complications. Dual lumen tubes may be useful in the presence of delayed gastric emptying (DGE) as the stomach may be decompressed while feeds are delivered to the jejunum. However, all feeding tubes placed in the small intestine, except direct jejunostomies, commonly dislodge and retroflex into the stomach. Jejunostomies are associated with less frequent, but more serious complications. These include intestinal torsion and bowel necrosis. PN is associated with septic, metabolic, and access-related complications and should be the feeding strategy of last-resort. Enteral feeds are clearly preferred over parental nutrition. A sound understanding of perioperative nutrition may improve patient outcomes. Patients undergoing pancreatic cancer surgery should undergo multidisciplinary nutrition screening and intervention, and the surgical/oncological team should include nutrition professionals in managing these patients in the perioperative period.     

The quest for accuracy of blood pressure measuring devices

The accuracy of blood pressure (BP) measuring devices is fundamental to good practice and scientific research. International guidelines on BP measurement are provided for clinicians who diagnose and treat patients with hypertension, clinical researchers who conduct trials on the efficacy of BP lowering drugs and interventional strategies, epidemiologists who conduct population surveys to determine the demographic consequences of hypertension on society, and researchers who perform meta‐analyses on published research to further influence the practice of medicine and the provision of resources. Although the outcomes of the endeavors of all these groups are dependent on the accuracy of BP measurements, the equipment is often of doubtful accuracy and the methodology of measurement is often poorly described and frequently not standardized. Thus, the fundamental element of hypertension evaluation has been largely ignored by both clinical practitioners and scientific researchers. Here, the authors briefly review the development of efforts to improve and validate the accuracy of BP measuring devices and highlight the deficiencies that persist. We conclude that, to protect the public from the serious consequences of inaccurate BP measurements, the following steps are required: (1) regulatory requirement for mandatory independent validation of all BP measuring devices using a universal protocol; (2) accreditation of laboratories for the performance of BP device validations; (3) online evaluation of validation studies with detection of protocol violations prior to publication of results; and (4) establishment of an independent scientific forum for the listing of accurate BP measuring devices.