A Subset of Patients With Recurrent Spontaneous Abortion Is Deficient in Transforming Growth Factor β-2-Producing “Suppressor Cells” in Uterine Tissue Near the Placental Attachment Site

PROBLEM : To determine if patients with unexplained recurrent miscarriage have a deficiency of decidual immunosuppressor cells that produce transforming growth factor β type 2, as has been found in mice with abortion due to rejection and/or trophoblast failure. METHODS : Decidual biopsy specimens were taken as near to the placental attachment site as possible under ultrasound guidance from first trimester legal termination (control) patients with recurrent miscarriage and non-viable pregnancy, and from patients with sporadic missed abortion. The tissue was tested for TGFβ-2⁺ suppressor cells by in situ hybridization, immunohistochemistry, and analysis of supernatants. RESULTS : TGFβ-2-related suppressor molecules similar but not identical to those identified in pregnant mice were released by decidual lymphoid cells. Fifty percent of 14 recurrent miscarriage patients showed a lack of suppressor cells and 59% were subnormal in comparison to 20 controls and 5 sporadic miscarriage patients, where 80–85% of the patients had detectable suppressor cells. CONCLUSIONS : Suppressor cell deficiency is compatible with a role for rejection and/or trophoblast failure in some patients with recurrent miscarriage. Presence of suppressor cells in most patients with missed abortion (4/5) is compatible with an alternative cause of fetal death, similar to findings reported in genetic fetal death mice.     

Safeguarding children: why an issue for pediatric anesthetists?

Child maltreatment and the responsibility of heath care professionals to assist in prevention and diagnosis is currently center stage in the United Kingdom. This subject has a very large literature base. Anesthetists were one of the first groups to have specific guidance on this subject, and key competencies are now part of the core curriculum for our trainees. This article seeks to briefly define maltreatment and provide statistics that outline the scale of the problem, and includes discussion of risk factors and recognition. We have focused on physical abuse and have provided a separate section on abusive head trauma, which is of particular importance to anesthetists. We also discuss the process of management, with some detail around Child Death Review procedures.     

Comparison of Biphasic and Monophasic Pulses: Does the Advantage of Biphasic Shocks Depend on the Waveshape?

With present implantable defibrillators, the ability to vary the defibrillation technique has been shown to increase the number of patients suitable for transvenous system. As newer waveforms become available, the need for a flexible device may change. In addition, although it has been shown that the option of biphasic waveform may increase the defibrillation efficacy, this may depend upon the shape of the biphasic waveform used. Thirty patients undergoing transvenous defibrillator implant were included in the study. In 20 patients (group I), defibrillation efficacy of simultaneous monophasic, sequential monophasic, and biphasic waveform with 50% tilt was determined randomly. Similarly, in ten patients (group II) testing of simultaneous monophasic shocks and biphasic waveforms with 65% and 80% tilt was performed in random order. The electrode system used consisted of two transvenous leads and a subcutaneous patch in all 30 patients. In group I, 50% tilt biphasic waveform consistently provided similar or better defibrillation efficacy compared to monophasic waveforms (biphasic 7.5 ±5.1 joules vs simultaneous 17 ± 7.8 joules, P < 0.01; and vs sequential 17 ± 8.4 joules, P <0.01). In group II, 65% tilt biphasic pulse required less energy for defibrillation as compared with simultaneous monophasic shocks (9.6 ± 4.5 joulesvs 15.6 ± 5.1 joules, P = 0.04). No significant difference was observed in terms of defibrillation threshold between 80% tilt biphasic shocks and simultaneous monophasic pulses (11.8 ± 6 joules vs 15.6 ±5.1 joules, P = NS). Biphasic shocks with smaller tilt delivered using a triple lead system more uniformly improved defibrillation threshold over standard monophasic waveforms.     

Biochemical characterization and localization of Fasciola hepatica 26-28 kDa diagnostic coproantigen

We have previously reported the usefulness of a 26-28 kDa coproantigen of Fasciola hepatica for diagnosis of infection. In this study, the 26-28 kDa coproantigen was biochemically characterized with the aid of monoclonal antibodies (MoAb) in an effort to better understand the biology of the antigen. Differential staining of chromatographically-purified 26-28 kDa coproantigen on SDS-PAGE, under reducing and non-reducing conditions, indicated that the coproantigen was a monomeric, highly glycosylated glycoprotein. Alkaline treatment of the purified coproantigen resulted in an 8 kDa protein core which still contained the epitope recognized by the MoAb. No protease activity was associated with the 26-28 kDa coproantigen. The coproantigen could be cleaved by trypsin without altering the reactive epitope recognized by the MoAb, but was resistant to pepsin digestion. Further, the coproantigen was stable under several different storage conditions. Indirect immunofluorescence on tissue sections of adult flukes indicated that the coproantigen was present in gut cells and tegument. Taken together these results confirm the stability of the 26-28 kDa coproantigen and its usefulness in diagnostic tests for F. hepatica infections.     

Intra-Atrial Reentrant Tachycardia After Palliation of Congenital Heart Disease:

Catheter Mapping of IART. introduction: The anatomic substrate of intra-atrial reentrant tachycardia (IART) following congenital heart surgery is poorly understood, but is presumed to be different than common atrial flutter. Methods and Results: To study the mechanisms of IART, we used a new technique for high-density endocardial mapping using recordings from a multipolar basket recording catheter (25 bipolar pairs). For each recording, biplane fluorographic reference points were digitized to obtain the spatial locations of electrode pairs, and activation times were calculated using temporal reference points from the surface ECG. Using custom software, data were combined to create three-dimensional atrial activation sequence maps, which were displayed as animated sequences. Using this technique, recordings were made in induced and/or spontaneous IART in 8 patients following congenital heart surgery (5 Fontan, 2 tetralogy of Fallot repair, 1 ventricular septal defect repair), and in 3 patients with normal intracardiac anatomy (I with type I atrial flutter). Ten discrete IART activation sequences were recorded; 2 patients had 2 sequences each. IART maps were constructed using a median of 108 electrode positions (range 27 to 197) from a median of 6 recordings/sequence (range 3 to 11). Sinus or paced atrial rhythms were also recorded, and maps were created in a similar fashion. Visual analysis of activation sequences of sinus and paced rhythm were anatomically concordant with known mechanisms of atrial activation. IART sequences revealed diverse mechanisms; only 1 IART circuit was similar to that associated with common atrial flutter. Activation wavefront emergence from presumed zones of slow conduction, lines of conduction block, and apparent bystander activation were observed. Conclusions: High-density atrial activation sequence maps demonstrate that IART following congenital heart surgery utilizes diverse circuits and is distinct from common atrial flutter. The technique used to create these three-dimensional activation sequences may improve understanding of these complex atrial arrhythmias and assist in the development of ablative therapies.     

Emerging Energy Sources for Catheter Ablation of Atrial Fibrillation

Catheter-based ablation techniques have been increasingly used as a curative therapy for treating atrial fibrillation (AF). Currently, radiofrequency (RF) energy is the most widely accepted and used method for catheter ablation of AF. However, RF ablation has potential disadvantages, including endocardial disruption, charring, platelet activation, pulmonary vein stenosis, and thrombus formation, and has limited efficacy in performing atrial linear ablation. As a result, new alterative energy sources have been explored for AF ablation. These new technologies, including cryoablation, microwave, ultrasound, and laser have different potential advantages over RF, but all of them have limited clinical experiences. Furthermore, the emergence of these new ablation energy sources should be paralleled with development of new ablation catheters, mapping and imaging tools to improve the successful rate of AF ablation. In the future, conventional RF ablation will remain the standard approach for AF, but some of these energies may be used in combination at specific sites for safety reasons, such as the use of cryoablation inside PVs or the use of microwave to create long atrial linear ablation more effectively.