Case report: acute unilateral loss of visual acuity after a visit to the dentist: an unusual complication after the use of an anesthetic combined with adrenaline

Occurrence of acute and unilateral blindness after local anaesthesia combined with adrenaline, for the treatment of dental caries. The blindness was caused by vasospasm of the central retinal artery. The dentists should be warned about possible visual complaints after use of local anaesthesia, which should urge them to refer the patient to the ophtalmologist.     

Influence of DCA on pulmonary (.-)V(O2) kinetics during moderate-intensity cycle exercise

PURPOSE: To test the hypothesis that pharmacological activation of the pyruvate dehydrogenase enzyme complex (PDC) with dichloroacetate (DCA) would speed phase II pulmonary oxygen uptake ((.-)V(O2)) kinetics after the onset of subsequent moderate-intensity (40-45% ((.-)V(O2)) peak) cycle exercise. METHODS: Seven healthy males (mean +/- SD age 25 +/- 4 yr, body mass 75.3 +/- 9.4 kg) performed four "square-wave" transitions from unloaded cycling to a work rate requiring 90% of the predetermined gas exchange threshold either with or without prior infusion of DCA (50 mg x kg body mass in 50 mL saline). Pulmonary ((.-)V(O2)) was measured breath-by-breath in all tests and ((.-)V(O2)) kinetics were determined from the averaged individual response to each condition using nonlinear regression techniques. RESULTS: The blood [lactate] measured immediately before the onset of exercise was significantly reduced in the DCA condition (C: 1.1 +/- 0.3 vs DCA: 0.6 +/- 0.3 mM; P < 0.01) consistent with successful activation of the PDC. However, DCA had no discernible effect on the rate at which ((.-)V(O2)) increased toward the steady state after the onset of exercise as reflected in the phase II time constant (C: 28.5 +/- 11.8 vs DCA: 29.4 +/- 14.9 s). CONCLUSIONS: The results suggest that PDC activation does not represent a principal intramuscular limitation to ((.-)V(O2)) kinetics after the onset of moderate-intensity exercise.     

Chronic fatigue syndrome: lack of association between pain-related fear of movement and exercise capacity and disability

BACKGROUND AND PURPOSE: Patients who experience pain, a symptom of chronic fatigue syndrome (CFS), often exhibit kinesiophobia (irrational fear of movement). The purpose of this study was to examine whether pain-related fear of movement is associated with exercise capacity, activity limitations, or participation restrictions in patients with CFS who experience widespread pain. SUBJECTS AND METHODS: Sixty-four subjects met the inclusion criteria. All subjects fulfilled the 1994 Centers for Disease Control and Prevention case definition for CFS and experienced widespread myalgias or arthralgias. The subjects completed the Tampa Scale for Kinesiophobia-Dutch Version (TSK-DV) and the Dutch Chronic Fatigue Syndrome-Activities and Participation Questionnaire (CFS-APQ). They then performed a maximal exercise test on a bicycle ergometer. Heart rate was monitored continuously by use of an electrocardiograph. Ventilatory factors were measured through spirometry. Correlations between the TSK-DV scores and both the exercise capacity data and the CFS-APQ scores were assessed using the Spearman rank correlation coefficient. Using the Mann-Whitney U test, the TSK-DV scores were compared between subjects who performed a maximal exercise stress test and those who did not perform the test. RESULTS: Forty-seven subjects (73.4%) attained a total score of greater than 37 on the TSK-DV, indicating high fear of movement. Neither the exercise capacity data nor the CFS-APQ scores indicated a correlation with the TSK-DV scores (n=64). Subjects who did not perform a maximal exercise capacity test had more fear of movement (median TSK-DV score=43.0, interquartile range=10.3) compared with those who did perform a maximal exercise capacity test (median TSK-DV score=38.0, interquartile range=13.2; Mann-Whitney U-test score=322.5, z=-1.974, P=.048), but the correlation analysis was unable to reveal an association between exercise capacity and kinesiophobia in either subgroup. DISCUSSION AND CONCLUSION: These results indicate a lack of correlation between kinesiophobia and exercise capacity, activity limitations, or participation restrictions, at least in patients with CFS who are experiencing widespread muscle or joint pain.     

Pregnancy in mice lacking the vitamin D receptor: normal maternal skeletal response,but fetal hypomineralization rescued by maternal calcium supplementation

Fetal mineralization appears to be driven by the pregnancy-induced stimulation of intestinal Ca absorption. We thus hypothesized that mineralization would be impaired in fetuses of mice that lack the vitamin D receptor (VDR). Here we report on the maternal response to pregnancy, and the fetal mineralization, in mice with a homozygous disruption of the VDR gene (VDR-/-) mated with wild-type (wt) males. We found that VDR-/- mice show mild hypocalcemia, clear rickets and osteomalacia on bone histomorphometry, lower cortical bone density on quantitative tomography, and reduced concentrations of calbindin-D9k (CaBP-D9k) in duodenal mucosa and kidney. The skeletal response to pregnancy was comparable in wt and VDR-/- mice; duodenal CaBP-D9k concentrations increased during pregnancy in VDR-/- as in wt mice, but remained 40% lower than in wt mice. We confirmed our hypothesis that mineralization is defective in d18.5 VDR+/- fetuses of VDR-/- mice, both by whole-body Ca determination and histomorphometric evaluation; the number of osteoclastic cells in bone was increased. The fetuses were hypercalcemic and had a 5-fold increase in circulating 1,25(OH)2D3. We then studied pregnancies in VDR-/- females, mated with wt males, fed a high Ca/P/lactose rescue diet during pregnancy. The rescue diet normalized the mineralization, the number of osteoclastic cells, and plasma Ca and 1,25(OH)2D3 concentrations in the fetuses. We interpret the data as evidence that, to ensure normal fetal mineralization, the maternal VDR-dependent intestinal Ca absorption can be substituted by passive Ca absorption entrained by a higher Ca intake. Alternatively or additionally, elevated 1,25(OH)2D3 in utero may disturb bone development.     

Left ventricular outflow obstruction in rhabdomyoma of infancy: meta-analysis of the literature

Primary heart tumors are exceptional in infants and children. Most common is the rhabdomyoma, often associated with tuberous sclerosis (Bourneville's disease). This tumor is generally believed to have no hemodynamic effects in the majority of cases. Recently, severe obstruction of the left ventricular outflow tract by a solitary tumor was diagnosed during pregnancy and emergency surgery was needed soon after birth.     

The combined analysis of P-glycoprotein expression and activity predicts outcome in childhood acute lymphoblastic leukemia

The link between drug resistance and relapse was often suggested, but rarely demonstrated in long-range clinical studies. Since it is nowadays recommended to validate immunocytochemical results, the authors studied prospectively 52 acute lymphoblastic leukemia (ALL) patients with an immunocytochemical test and a functional flow cytometric test. The 4-year EFS and OS were 79.3% and 85.2%, respectively. Patients scoring positive in both tests had a significantly higher relapse rate and worse survival (log rank p = .007 and .047 for event-free survival and overall survival, respectively). Among the different prognostic variables evaluated, only the combination of P-gp expression and activity was a statistically significant parameter predicting relapse in childhood ALL.     

Oxygen uptake kinetics during high-intensity arm and leg exercise

The purpose of the present study was to examine the oxygen uptake kinetics during heavy arm exercise using appropriate modelling techniques, and to compare the responses to those observed during heavy leg exercise at the same relative intensity. We hypothesised that any differences in the response might be related to differences in muscle fibre composition that are known to exist between the upper and lower body musculature. To test this, ten subjects completed several bouts of constant-load cycling and arm cranking exercise at 90% of the mode specific V(O(2)) peak. There was no difference in plasma [lactate] at the end of arm and leg exercise. The time constant of the fast component response was significantly longer in arm exercise compared to leg exercise (mean+/-S.D., 48+/-12 vs. 21+/-5 sec; P < 0.01), while the fast component gain was significantly greater in arm exercise (12.1+/-1.0 vs. 9.2+/-0.5 ml min(-1) W(-1); P < 0.01). The V(O(2)) slow component emerged later in arm exercise (126+/-27 vs. 95+/-20 sec; P < 0.01) and, in relative terms, increased more per unit time (5.5 vs. 4.4% min(-1); P < 0.01). These differences between arm crank and leg cycle exercise are consistent with a greater and/or earlier recruitment of type II muscle fibres during arm crank exercise.     

In vitro susceptibility to infection with SIVcpz and HIV-1 is lower in chimpanzee than in human peripheral blood mononuclear cells

This study was undertaken to evaluate and compare the susceptibility of chimpanzee versus human peripheral blood mononuclear cells (PBMCs) to infection with SIVcpz and HIV-1 non-syncitium inducing primary isolates. The results demonstrate clearly that chimpanzee PBMCs have a lower capacity to support viral replication as compared to human PBMCs. There was no experimental evidence that this difference was due to a lower availability of target cells for viral infection (PBMCs positive for CD4 and CCR5 molecules) or to a differential susceptibility to apoptosis (PBMCs positive for CD4 and CD95 molecules). A lower capacity of chimpanzee PBMCs to support SIVcpz and HIV-1 replication in vitro is related to a post-entry barrier to virus replication.     

Use of an event recorder in the decision for pacemaker implantation in a child with syncope

The use of a patient-triggered and automatic event recorder is documented in a 17-month-old girl presenting with paroxysmal episodes of loss of consciousness. After pacemaker implantation, the paroxysmal attacks disappeared. CONCLUSION: we recommend a more frequent use of the event recorder in the investigation of syncope, especially in small children.     

Evaluation of 4-mm to 7-mm versus 6-mm prosthetic brachial-antecubital forearm loop access for hemodialysis: results of a randomized multicenter clinical trial

OBJECTIVE: Prosthetic arteriovenous fistulas for hemodialysis vascular access have a high incidence rate of thrombotic occlusions that result in graft failure. This randomized multicenter study was performed to assess the patency rates and the effect of 4-mm to 7-mm grafts on the development of stenoses. METHODS: A total of 109 patients who needed vascular access for hemodialysis were randomized to receive either 6-mm (n = 57) or 4-mm to 7-mm prosthetic brachial-antecubital forearm loop accesses (polytetrafluoroethylene). Duplex scanning, with measurement of blood flow and peak systolic velocity and detection of stenoses (>50%), was performed at 1, 6, and 12 months after surgery. Clinical data were obtained in a prospective manner and primary, assisted primary, and secondary patency rates were calculated with the Kaplan-Meier life-table analysis. Statistical analysis was performed with the independent samples t test and chi(2) test. RESULTS: At 1 year, patency rates were similar for both 4-mm to 7-mm and 6-mm prostheses (primary, 46% versus 43%; assisted primary, 62% versus 58%; secondary, 87% versus 91%). The incidence rate of thrombotic occlusion was comparable for both groups (0.74/patient-year versus 0.88/patient-year; P >.05). Mean graft flow at 1, 6, and 12 months was 1416 versus 1415 mL/min, 1345 versus 1319 mL/min, and 1595 versus 1265 mL/min (P >.05) for 4-mm to 7-mm and 6-mm grafts, respectively. Also, no differences in peak systolic velocities in any part of the grafts were observed. The percentage of stenoses detected was equal in both groups at 1 year after surgery (27% versus 20%; P >.05). CONCLUSION: A 4-mm to 7-mm tapered prosthetic brachial-antecubital forearm loop access did not reduce the incidence rates of stenoses and thrombotic occlusions compared with a 6-mm prosthetic conduit. Moreover, no differences in patency rates were observed. Therefore, we believe that the 4-mm to 7-mm graft should not be used routinely for hemodialysis vascular access.