The impact of universal screening for gestational glucose intolerance on outcome of pregnancy

Universal screening for gestational glucose intolerance has strong support, despite the lack of scientific evidence documenting its benefit. In the early 1980s, practicing obstetricians were split concerning the clinical importance of gestational glucose intolerance, so that some practitioners tested virtually all the patients they treated while others tested none. This historical reality provided concurrent screened and unscreened populations in whom to assess the impact of screening. We studied all 1,307 singleton pregnancies cared for and delivered at the New York Hospital-Cornell University Medical Center during a five month period. Large infants (birth weight greater than or equal to 4,000 grams) were born to 10.5 per cent of the women who were not screened (533) and to 11.2 per cent of the women who were screened (774). The process of screening not only failed to decrease the rate of large infants, but also failed to improve otherwise pregnancy outcomes and was associated with more intensive surveillance during pregnancy and a significantly higher rate of primary cesarean delivery. Given the unexpected concomitants of the screening process, we conclude that recommendations for universal screening for gestational glucose intolerance should be reconsidered.     

Effects of combining inducible nitric oxide synthase inhibitor and radical scavenger during porcine bacteremia

Complex interactions of nitric oxide and other free radicals have been implicated in the pathogenesis of sepsis and organ dysfunction. We hypothesized that simultaneous inducible nitric oxide synthase inhibition (L-N6-[1-iminoethyl]-lysine [L-NIL]) and neutralization of superoxide (O2-) (4-hydroxy-2,2,6,6-tetramethylpiperidine-N-oxyl [Tempol]) would protect from detrimental consequences of long-term, volume-resuscitated, hyperdynamic porcine bacteremia. In this prospective, randomized, controlled experimental study, 16 anesthetized, mechanically ventilated and instrumented pigs were exposed to 24 h of continuous infusion of live Pseudomonas aeruginosa. After 12 h of hyperdynamic sepsis, animals were randomized to receive either vehicle (control, n = 8) or combination of L-NIL and Tempol (n = 8). Systemic and hepatosplanchnic hemodynamics, oxygen exchange, metabolism, ileal mucosal microcirculation and tonometry, oxidative stress and coagulation parameters were assessed before, 12, 18, and 24 h of P. aeruginosa infusion. Combined treatment inhibited sepsis-induced increase in plasma nitrate/nitrite, 8-isoprostane, and thiobarbituric acid reactive species concentrations, prevented hypotension, and reversed hyperdynamic circulation. Despite lower intestinal macrocirculation, combined regimen attenuated the otherwise progressive deterioration in ileal mucosal microcirculation and prevented mucosal acidosis. Treatment substantially attenuated mesenteric and hepatic venous acidosis, preserved sepsis-induced impairment of hepatosplanchnic redox state, and prevented the development of renal dysfunction. Finally, coinfusion of L-NIL and Tempol largely attenuated the sepsis-induced rise in plasma von Willebrand factor and thrombin-antithrombin complexes. Thus, hemodynamic, microcirculatory, metabolic, renal, and coagulation data indicate that combining inducible inhibition with cell permeable O2(-) radical scavenger afforded significant protection in porcine sepsis, thus suggesting an important interactive role of O2(-) and nitric oxide in mediating organ dysfunction.     

The effects of 8 weeks of endurance running on hepcidin concentrations, inflammatory parameters, and iron status in female runners

Exercise-associated iron deficiency is a common disorder in endurance athletes. The authors investigated the effects of long-term endurance exercise on hepcidin concentrations, inflammatory parameters, and iron status in moderately trained female long-distance runners. Eighteen runners were assigned to either an interval- or a continuous-training exercise group. The physical training consisted of two 3-week progressive overload periods, each followed by a week's recovery, and concluded with a 10- or 21-km competitive run. Samples were taken 6 times during the 8-wk training program, first at baseline (BPre), then after the first and second 3-wk training loads (TPost1, TPost2), after each recovery week (Recovery1 and Recovery2), and poststudy (BPost). Soluble transferrin receptor (sTfR) concentrations were increased in Recovery2 and BPost compared with BPre (p=.02), hemoglobin decreased in TPost1 and TPost2 (p<.001), and red blood cells decreased in TPost2 (p=.01). Hepcidin decreased with time in TPost1 and in BPost compared with BPre (p<.001) and increased in TPost2 compared with TPost1 (p<.001). No differences over time were found for high-sensitivity C-reactive protein. The main findings of the current study indicate that serum hepcidin and sTfR were affected after 8 weeks of endurance running in women. No positive relation was found with inflammation.     

Colpodella spp.-like parasite infection in woman, China

The phylum Apicomplexa comprises intracellular protozoa that include many human pathogens. Their nearest relatives are chromerids and colpodellids. We report a case of a Babesia spp.-like relapsing infection caused by a newly described microorganism related to the Apicomplexa. This case is highly suggestive of a previously undescribed type of colpodellid that infects vertebrates.     

Reduction of atrial tachyarrhythmia episodes during the overdrive pacing period using the post–mode switch overdrive pacing (PMOP) algorithm

BACKGROUND: Early recurrences within 10 minutes after termination of an atrial tachyarrhythmia, such as atrial tachycardia (AT), atrial flutter, or atrial fibrillation (AF) episodes, account for a large part of paroxysmal AT/AF episodes. It is unclear whether these arrhythmias can be suppressed by overdrive pacing. OBJECTIVE: We set out to prove that overdrive pacing is effective in preventing early recurrences of AT/AF. METHODS: This AT500 (DDDRP device, Bakken Research Center Medtronic, Maastricht, The Netherlands) post-mode switch overdrive pacing (PMOP) study is a randomized controlled trial designed to test the efficacy of overdrive pacing on the suppression of early recurring AT/AF episodes. With the PMOP feature, overdrive pacing is activated 12 ventricular beats after device-confirmed termination of an AT/AF episode with a programmed duration and rate. If at least four episodes of 1 minute in duration occurred within the run-in period of 1 month, patients were randomized to one of the three settings (PMOP off and PMOP 10 minutes at 90 bpm or 120 bpm) for 2 months. At 2 and 4 months, patients were crossed over to another arm. At 6 months, all patients were programmed with PMOP on at 90 bpm for 30 minutes. RESULTS: We enrolled 122 and randomized 50 patients. Sixty percent of all stored AT/AF episodes occurred within 10 minutes after a previous episode; 31% occurred after device-determined termination and before the device reached the overdrive rate (17-27 ventricular beats after termination), and 29% of the episodes occurred while the device was pacing at the programmed overdrive rate. Thirty-seven percent of the average percentage of episodes during the overdrive period was prevented by the randomized settings of PMOP 90 bpm/10 min (P = .01, paired t-test, n = 39) and 120 bpm/10 min (P = .03, n = 35). In addition, for the nonrandomized setting of PMOP 90 bpm/30 min, the average number of episodes during the overdrive period was significantly smaller than the percentage of episodes occurring during the corresponding off period of 30 minutes (P = .05, n = 33). No significant differences in burden and episodes were found between the PMOP settings and the corresponding off periods. CONCLUSIONS: This is the first randomized controlled clinical trial to prove that overdrive pacing is effective in preventing early recurrences of AT/AF. However, shortcomings of the PMOP algorithm, such as late activation, need further improvement.     

Assessment of vertical changes during maxillary expansion using quad helix or bonded rapid maxillary expander

Objective:To determine if there is a significantly different effect on vertical changes during phase I palatal expansion treatment using a quad helix and a bonded rapid maxillary expander in growing skeletal Class I and Class II patients.Materials and Methods:This retrospective study looked at 2 treatment groups, a quad helix group and a bonded rapid maxillary expander group, before treatment (T1) and at the completion of phase I treatment (T2). Each treatment group was compared to an untreated predicted growth model. Lateral cephalograms at T1 and T2 were traced and analyzed for changes in vertical dimension.Results:No differences were found between the treatment groups at T1, but significant differences at T2 were found for convexity, lower facial height, total facial height, facial axis, and Frankfort Mandibular Plane Angle (FMA) variables. A comparison of treatment groups at T2 to their respective untreated predicted growth models found a significant difference for the lower facial height variable in the quad helix group and for the upper first molar to palatal plane (U6-PP) variable in the bonded expander group.Conclusion:Overall, both the quad helix expander and the bonded rapid maxillary expander showed minimal vertical changes during palatal expansion treatment. The differences at T2 suggested that the quad helix expander had more control over skeletal vertical measurements. When comparing treatment results to untreated predicted growth values, the quad helix expander appeared to better maintain lower facial height and the bonded rapid maxillary expander appeared to better maintain the maxillary first molar vertical height.     

Effects of continuous venovenous haemofiltration-induced cooling on global haemodynamics, splanchnic oxygen and energy balance in critically ill patients.

BACKGROUND: A number of haemodialysis studies have demonstrated beneficial effects of cooler dialysates on global haemodynamics in chronic dialysis patients. However, the effects of continuous venovenous haemofiltration (CVVH)-induced cooling on regional perfusion and energy metabolism in critically ill septic patients have not been well defined. METHODS: Nine septic mechanically ventilated patients (age 40-69 years) were investigated during CVVH (ultrafiltration 30-35 ml/kg/h). Baseline data (=WARM 1) were collected when core temperature (Tc) was >37.5 degrees C; the second data set (=COLD) was obtained after 120 min of 'cooling'; and a third set (=WARM 2) was obtained after 120 min of 'rewarming'. During 'warming' (WARM 1 and 2, respectively), both substitution fluids (SFs) and 'returned' blood (RB) were warmed (37 degrees C), whereas during 'cooling', the SFs were at 20 degrees C and RB was not warmed. We measured hepatic venous (HV) haemoglobin oxygen saturation (ShvO(2)), blood gases, lactate and pyruvate. Gastric mucosal PCO(2) (PgmCO(2)) was measured by air tonometry and the gastric mucosal - arterial PCO(2) difference (PCO(2) gap) was calculated. Haemodynamic monitoring was performed with arterial and pulmonary arterial thermodilution catheters. RESULTS: Tcs were significantly altered [WARM 1, 37.9 degrees C (37.6, 38.3); COLD, 36.8 degrees C (36.3, 37.1); WARM 2, 37.5 degrees C (37.0, 38.0); P<0.001; data are median, 25th and 75th percentiles, respectively]. Systemic vascular resistance significantly increased during cooling. As a result, mean arterial pressure increased. Cooling was associated with significant decreases in heart rate, cardiac output, systemic oxygen delivery and consumption. ShvO(2) did not change [WARM 1, 51.0% (44.0, 59.5); COLD, 49.0% (42.0, 58.0); WARM 2, 51.0% (46.0, 57.0); P = NS]. The splanchnic oxygen extraction ratio, the HV lactate to pyruvate ratio, HV acid base status and PCO(2) gap remained unchanged. CONCLUSION: Mild core cooling induced by CVVH may not affect hepatosplanchnic oxygen and energy balance in septic critically ill patients, even though it affects global haemodynamics.     

Preoperative characteristics predicting intraoperative hypotension and hypertension among hypertensives and diabetics undergoing noncardiac surgery.

We prospectively studied patients with hypertension and diabetes undergoing elective noncardiac surgery with general anesthesia to test the hypothesis that patients at high risk for prognostically significant intraoperative hemodynamic instability could be identified by their preoperative characteristics. Specifically we hypothesized that patients with a low functional capacity, decreased plasma volume, or significant cardiac comorbidity would be at high risk for intraoperative hypotension and those with a history of severe hypertension would be at risk for intraoperative hypertension. Patients who had a preoperative mean arterial pressure (MAP) greater than or equal to 110, a walking distance of less than 400 m, or a plasma volume less than 3000 cc were at increased risk of intraoperative hypotension (i.e., more than 1 hour of greater than or equal to 20 mmHg decreases in the MAP). Hypotension was also more common among patients having intra-abdominal or vascular surgery, and among those who had operations longer than 2 hours. Patients older than 70 years or with a decreased plasma volume were at increased risk of having more than 15 minutes of intraoperative elevations of greater than or equal to 20 mmHg over the preoperative MAP in combination with intraoperative hypotension; this was also more common when surgery lasted more than 2 hours. Patients who had intraoperative hypotension tended to have an immediate decrease in MAP at the onset of anesthesia and were often purposefully maintained at MAPs less than their usual level during surgery with fentanyl and neuromuscular blocking agents. Patients who had intraoperative hyper/hypotension tended to have repeated elevations in MAP above their preoperative levels during the course of surgery, and such elevations precipitated interventions with neuromuscular blocking agents and/or fentanyl. Neither pattern was more common among patients who developed net intraoperative negative fluid balances. Both hypotension and hyper/hypotension were associated with increased renal and cardiac complications after operation. Patients with cardiac disease, especially diabetics, and those with negative fluid balances also had increased complications. Preoperative characteristics influence the susceptibility to intraoperative hypotension and hypertension, which are related to postoperative complications.     

Permeability of pig urinary bladder wall: time and concentration dependent effect of chitosan

Chitosan in 0.5% w/v concentration enhanced the permeability of the isolated pig urinary bladder wall by desquamation of the urothelium as ascertained in our previous study. The aim of the present work was to determine the time and concentration dependence of chitosan's effect on the permeation of a model drug into the bladder wall and to establish if the mechanism of permeation enhancement depends on the concentration of chitosan used. In the permeability studies performed by the use of diffusion cells, transport of a model drug moxifloxacin into the isolated pig urinary bladder wall was determined. For morphological observations of the urothelium in response to chitosan treatment scanning and transmission electron microscopy were applied. Within 90 min the effect of chitosan on the tissue amounts of moxifloxacin gradually increased and approached its plateau. In one hour even 0.0005% w/v dispersion of chitosan significantly enhanced the permeability of the pig urinary bladder wall for the model drug and at 0.001% w/v concentration the maximal effect on the tissue permeability was achieved. All concentrations of chitosan that significantly enhanced the permeability of the bladder wall triggered necrosis of superficial cells or desquamation of the urothelium. However, at lower concentrations and shorter exposure times the damage of the urothelium was limited to the changes in tight junctions. Chitosan was ascertained to increase the permeation of moxifloxacin into the urinary bladder wall in a time and concentration dependent manner.