Gastrointestinal Issues in Infants and Children with Autism and Developmental Delays

Controversy exists regarding whether gastrointestinal (GI) issues play a role in the symptomatology of autism spectrum disorder (ASD). While some studies have found GI problems to be more prevalent in individuals with ASD, others have reported no such difference. Studies looking at the relationship between GI issues and ASD symptom severity have also had mixed results. The current study examined 112 participants between the age of 17 to 37 months. Participants comprised four groups of 28 children: an ASD and no GI issues group, an ASD with GI problems group, an atypical development and no GI issues group, and an atypical development with GI issues group. The results of the current study suggest that although the prevalence of GI symptoms was higher in participants with ASD than those without, this difference was not significant. The study also found that GI issues were not related to ASD symptom severity or developmental functioning.     

Endogenous Opioid Function and Responses to Morphine: The Moderating Effects of Anger Expressiveness

Long-term use of opioid analgesics may be ineffective or associated with significant negative side effects for some people. At present, there is no sound method of identifying optimal opioid candidates. Individuals with chronic low back pain (n = 89) and healthy control individuals (n = 102) underwent ischemic pain induction with placebo, opioid blockade (naloxone), and morphine in counterbalanced order. They completed the Spielberger Anger-Out subscale. Endogenous opioid function × Anger-out × Pain status (chronic pain, healthy control) interactions were tested for morphine responses to ischemic threshold, tolerance, and pain intensity (McGill Sensory and Affective subscales) and side effects. For individuals with chronic pain and healthy control participants, those with low endogenous opioid function and low anger-out scores exhibited the largest morphine analgesic responses, whereas those with high anger-out and low endogenous opioid function showed relatively weaker morphine analgesic responses. Further, individuals with chronic pain with low endogenous opioid function and low anger-out scores also reported the fewest negative effects to morphine, whereas those with low endogenous opioid function and high anger-out reported the most. Findings point toward individuals with chronic pain who may strike a favorable balance of good analgesia with few side effects, as well as those who have an unfavorable balance of poor analgesia and many side effects.

Role of angiotensin II in dietary modulation of rat late distal tubule bicarbonate flux in vivo.

We have reported that overnight fasting stimulates bicarbonate reabsorption (JtCo2) in rat distal tubules. The present in vivo microperfusion studies evaluated the hypothesis that endogenous angiotensin II (AII) mediates this response. Rat late distal (LD) tubules were perfused at 8 nl/min in vivo with a hypotonic solution containing 28 mM bicarbonate. In overnight-fasted rats, LD JtCO2 was significantly higher than in normally fed rats (50 +/- 4 vs. 16 +/- 6 pmol/min.mm, P < 0.05). When overnight-fasted rats were salt-loaded, JtCO2 fell significantly (38 +/- 3 pmol/min.mm, P < 0.05). Conversely, in fed rats ingesting a zero-salt diet, JtCO2 increased three-fold (45 +/- 5 pmol/min.mm, P < 0.05). Enalaprilat infusion (0.25 micrograms/kg body wt, intravenously), in these zero-salt and overnight-fasted rats, reduced LD JtCO2 values to normal. Further, infusion of losartan (5 mg/kg body wt, intravenously), the specific AII AT1 receptor blocker, reduced JtCO2 in overnight-fasted rats by two-thirds (16 +/- 4 pmol/min.mm, P < 0.05). Finally, we perfused 10(-11) M AII intraluminally with and without 10(-6) M losartan: AII increased JtCO2 to 45 +/- 6 pmol/min.mm, equal to the zero-salt flux. This was completely abrogated by simultaneous losartan perfusion. Therefore, these results suggest that AII is an in vivo stimulator of late distal tubule bicarbonate reabsorption.     

An empirical evaluation of the performance of antibody identification tasks

Four empirical studies were conducted for better understanding of the nature of problem-solving activities by medical technologists and medical technology students when performing antibody identification tasks. The results indicated the importance of strategies that ensure the collection of converging evidence, as these strategies protect against the fallibility of commonly used heuristics and against errors due to simple slips. The results also indicate that not only do students make significant numbers of errors, but so do practicing technologists. In one of the studies covering a 1-year period, for instance, a group of 16 technologists made a total of 41 errors in 1057 cases. On the basis of these findings, several alternatives are proposed to reduce errors.     

Ricinoleic acid effect on the electrical activity of the small intestine in rabbits.

Using myoelectric recording techniques, we examined the myoelectric effects of castor oil; ricinoleic acid (cis isomer), the active ingredient of castor oil; and ricinelaidic acid (trans isomer) in the small intestine of New Zealand white rabbits. Ricinoleic acid, 2 microgram/kg per min (6mM), was perfused into a distal 12-cm ileal loop. An abnormal myoelectric pattern developed that was similar to the alteration in the electrical activity that has previously been reported for cholera enterotoxin. Castor oil, 0.85 ml/kg, had a similar effect. Ricinelaidic acid, 2 microgram/kg per min, induced no activity. A second preparation consisted of an intraluminal perfusion of ricinoleic acid, 2 microgram/kg per min, into the first section of the duodenum. The abnormal myoelectric pattern was observed in the jejunum and the ileum but not the duodenum. The mean onset time for the development of this altered myoelectric state for all experiments was 3.5 h. These studies suggest that an active motility component in addition to the secretory state exists throughout the small intestine that is exposed to castor oil or ricinoleic acid.     

Are Metastases Really Hypovascular in the Arterial Phase?

OBJECTIVE: The purpose of this study was to describe enhancement and vascularity characteristics of liver metastases on real-time low-mechanical index contrast-enhanced ultrasonography. METHODS: This retrospective study was approved for chart review by our Research Ethics Board. Informed consent was waived. Fifty metastases (colorectal [n = 28], neuroendocrine [n = 6], pancreatic [n = 6], melanoma [n = 3], and other [n = 7]) in 50 patients (38-84 years, 24 male and 26 female) were analyzed. Contrast-enhanced ultrasonography was performed after intravenous injection of a microbubble contrast agent. Two radiologists independently reviewed digital cine clips and static images for the arterial phase intensity and pattern of enhancement and the presence of dysmorphic vessels. Observations on wash-out included its presence and completeness. Disagreement was resolved by consensus. The interval to peak arterial enhancement and beginning of wash-out were determined. Reader agreement was estimated with the kappa statistic. RESULTS: All but 6 metastases (44/50 [88%]) showed arterial hypervascularity, with dysmorphic vessels in 21 (42%) of 50. The pattern of enhancement was rim in 21 (42%) of 50 and diffuse in 29 (58%) of 50. The time to peak arterial enhancement ranged from 8 to 27 seconds (mean, 15.1 seconds), and the beginning of wash-out ranged from 13 to 50 seconds (mean, 25.2 seconds). Although a thin margin of residual enhancement was seen in 27 (54%) of 50 lesions in the early wash-out phase, all lesions (50/50) showed uniform complete wash-out in the portal phase. CONCLUSIONS: Contrary to popular belief based on computed tomography and magnetic resonance imaging studies, most hepatic metastases, including those thought to be hypovascular, show transient arterial hypervascularity on contrast-enhanced ultrasonography, followed by rapid and complete wash-out initiated within the conventional arterial phase.     

Do hip replacements improve outcomes for hip fracture patients?

BACKGROUND: Hip fracture is a common problem among older Americans. Two types of procedures are available for repairing hip fractures: hip replacement and open or closed reduction with or without internal fixation. The assumption has been that hip replacement produces better functional outcomes. Although that is the common wisdom, outcome studies evaluating hip replacement for treatment of hip fracture are few and have not clearly documented its superiority. OBJECTIVES: To compare outcomes of hip fracture patients who receive hip replacement versus another stabilizing procedure (open or closed reduction with or without internal fixation). DESIGN: Prospective cohort study. PARTICIPANTS: We studied 332 patients (age, > 65) who were hospitalized for a femoral neck fracture and discharged alive. MEASUREMENTS: We examined 2 treatment groups, hip replacement versus another procedure, on 6 outcomes [Activities of Daily Living (ADLs), walking, living situation (institutionalized or not), perceived health (excellent/good vs. fair/poor), rehospitalization, and mortality] at 3 postdischarge times (6 weeks, 6 months and 1 year). RESULTS: Mean age was 80, 80% were female, 96% White, 28% married, and 71% had a hip replacement. The treatment groups were similar at baseline (3 months before admission as reported at discharge) on ADLs, walking, living situation, and perceived health (all P > 0.24). After adjusting for demographics, clinical characteristics, fracture characteristics, and prior ADLs, walking ability, living situation, and perceived health, patients with a hip replacement did not do better at 6 weeks, 6 months, or 1 year post-discharge on any of the 6 outcome measures (all 18 P > 0.10). A global test of all 6 outcomes finds hip replacement patients doing less well at one year (P = 0.02). CONCLUSIONS: Despite the commonly held belief that hip replacement is a superior treatment for hip fracture, we found no suggestion of better outcomes for hip replacement on any of 6 key outcomes.     

SPECIFIC BINDING OF LEUCYL TRANSFER RNA TO AN IMMATURE FORM OF L-THREONINE DEAMINASE: ITS IMPLICATIONS IN REPRESSION

The in vitro assembly of L-threonine deaminase from its constituent parts results in the formation of an inactive species of this enzyme which specifically and reversibly binds leucyl-tRNA. The native, catalytically active enzyme, which is derived from this species in the presence of maturation-inducing ligands, does not bind tRNA. The possible involvement of this protein-tRNA complex in the repression of the ilv (ADE) operon is discussed.