Prolonged measurement improves the assessment of the barrier function of the esophago-gastric junction by high-resolution manometry

BACKGROUND

Etiology of gastro-esophageal reflux disease (GERD) is multifactorial, but incompetence of the esophago-gastric junction (EGJ) appears to be of crucial importance. Established manometric parameters for assessment of EGJ barrier function are sub-optimal, potentially because they reflect only a very brief (up to 30 seconds), not necessarily representative period. This prospective, case-control study tested the performance of novel, high-resolution manometry (HRM) parameters of EGJ function in the assessment of GERD.

METHODS

Patients with reflux symptoms and healthy controls (HC) underwent standard HRM and 24-hour pH±impedance measurements. EGJ morphology, lower esophageal sphincter pressure integral (LES-PI), EGJ contractile integral (EGJ-CI) were compared with total-EGJ-CI, a novel parameter summarizing EGJ barrier function during the entire HRM protocol. Esophageal acid exposure ≥4.2%/24 h (A-Reflux-pos) or ≥73 reflux episodes in 24 hours (V-Reflux-pos) were considered pathological.

KEY RESULTS

Sixty five HC and 452 patients completed HRM, 380 (84%) patients underwent ambulatory reflux-monitoring. LES-PI, EGJ-CI and total-EGJ-CI correlated with EGJ morphology subtypes (all P<.00001). Only total-EGJ-CI was consistently lower in A-Reflux-pos and V-Reflux-pos subjects compared with HC and patients without GERD. Total-EGJ-CI was also the single best parameter for prediction of pathological reflux (optimal cut-off 47 mmHg cm, AUC 0.746, P<.0001). This cut-off value, approximately 1 SD below the mean normal value, showed modest sensitivity 54% and positive predictive value 46%, but good specificity 85% and negative predictive value 89% for GERD diagnosis.

CONCLUSION & INFERENCES

Total EGJ-CI, a new metric that summarizes EGJ contractility over time, allows an improved assessment of EGJ barrier function. Pathological reflux is unlikely if this metric is within the upper two-thirds of the normal range.

Tibia fractures produced from the impact of a baseball bat

Forty-seven patients presented during a 1-year period with fractures of the extremities produced by the impact of a baseball bat. This represented an increase of fourfold in fractures associated with baseball bat trauma as compared with the previous year. Those patients with tibia fractures were retrospectively reviewed in terms of associated soft-tissue injuries, fracture pattern, and fracture healing. Potential force generated and kinetic energy transferred when a baseball bat strikes the tibia were calculated mathematically to provide correlation with clinical observations. Tibia fractures produced by baseball bats represented 10% of all tibia fractures presenting from July 1990-July 1991. Of these 11 tibia fractures, 3 developed compartment syndrome, necessitating fasciotomy and subsequent skin grafting, and 1 developed osteomyelitis, which eventually resulted in amputation. One patient had superficial skin blistering that required a delay in definitive fracture care of 11 days and subsequent skin grafting. There was one nonunion and three delayed unions requiring additional operative intervention. This incidence of compartment syndrome (27%) is nine times higher than the overall incidence, at this institution, of compartment syndrome (3%) in tibia fractures produced by other mechanisms. The maximum potential kinetic energy produced during the impact of a baseball bat is 515 kg/m2/s2: 25% higher than that produced by a 9-mm bullet fired at a distance of 6 ft (407 kg/m2/s2). The potential force transmitted from a bat to the tibia at the time of collision is 8,000 lb, three times that of the bullet (626 lb).(ABSTRACT TRUNCATED AT 250 WORDS)

Effects of a high-density intramammary device on mammary glands, production, and reproductive performance in dairy cows

A clinical field trial was undertaken to determine the influence of an intramammary device (IMD) on environmental mastitis and production. On 4 central California dairies, 200 Holstein first-lactation cows were randomly assigned to 2 groups. Cows in the treatment group were fitted with an IMD, and cows in the control group were not. The incidence of clinical mastitis for the 2 groups was determined during the study period. Bacteriologic monitoring at intervals over 2 lactations (lactation 2 and through 60 days of lactation 3) was used to determine the incidence of subclinical infection. In addition, data were collected to determine whether the groups differed in milk production, butterfat production, post-milking and test-day somatic cell counts, and reproductive efficiency. Total milk production and butterfat production over the 2 lactation periods did not vary significantly between the groups. Also, the groups did not differ in calving-to-conception interval, duration of lactation, calving interval, and calving-to-first service interval. Cows with IMD were significantly less likely to develop clinical mastitis (5% vs 13%) than control cows. The IMD did not appear to affect subclinical infection rates (minor pathogens only) except at day 300 of lactation 2 and at day 10 of lactation 3, when prevalence was greater in the cows with IMD. The minor pathogens were predominately (80%) coagulase-negative staphylococci. It was unusual to have coagulase-negative staphylococci in the same quarter at 2 consecutive samplings, prompting the speculation that during lactation, the duration of coagulase-negative staphylococci infection is short (resolves without intervention).(ABSTRACT TRUNCATED AT 250 WORDS)

Comparison of AOAC and Atomic Absorption Spectrophotometry Methods for Determining Sodium in Fertilizers: Collaborative Study

A collaborative study was carried out to compare AOAC method 2.147-2.150 for determining sodium in fertilizers with the atomic absorption spectrophotometric (AAS) method. Twelve synthetic NPK samples, 6 pairs of blind duplicates (0.06-8.5% Na), were sent to 22 collaborators; a total of 13 sets of results were received and evaluated by the modified matched pairs technique. The AAS method showed better performance in samples with low sodium content and high potassium content. The AAS method has been adopted official first action for determining sodium in fertilizers.

Ultrastructural alterations in Tetrahymena pyriformis induced by growth on saturated phospholipids at 40.1 degrees C

Structural changes in Tetrahymena pyriformis, strain WH-14, induced by growth on saturated phospholipids at 40.1 degrees C, uere studied by electron microscopy. Alterations in the ultrastructural organizations of the cell membrane and surface regions were common. These alterations were characterized in the displacement of kinetosomes, the spatial disorientation and disorganization of cortical ridges and grooves, and the spatial disorientation of longitudal and transverse microtubular ribbons. Irregular surface protrusions and multiple invaginations of alveolar membranes were among the most common features encountered. Disorganization of longitudinal microtubular ribbons was also a frequent encounter. The integrity of the ultrastructure of cell surface membranes and of the internal organization and ultrastructure of the kinetosomes, however, appeared to be unaltered. Other alterations included those of a number of cytoplasmic organelles (e.g. mitochondria and endoplasmic reticulum), which showed characteristic changes in the structural patterns.