Progressive interstitial pneumonia associated with myelodysplastic syndrome: Implication of superoxide hyperproduction by neutrophils

Abstract Interstitial pneumonia and aseptic neutrophilic infiltration in the lung are rare pulmonary manifestations of myelodysplastic syndrome (MDS). We report a patient with progressive interstitial pneumonia associated with MDS. Histological examination of the lung revealed infiltration of atypical haematopoietic cells associated with MDS and diffuse alveolitis with honeycombing. Neutrophils obtained from the patient showed superoxide hyperproduction after stimulation with phagocytosis and phorbol myristate acetate, which might be attributed to the pathogenesis of interstitial pneumonia.     

Vasopressin plus oxygen vs vasopressin alone in cirrhotic patients with portal-hypertensive gastropathy: Effects on gastric mucosal haemodynamics and oxygenation

The effects of vasopressin plus oxygen and vasopressin alone on gastric mucosal perfusion and oxygenation were studied using reflectance spectrophotometry and laser Doppler velocimetry in 23 cirrhotic patients with portal-hypertensive gastropathy. The measurements were performed under basal conditions and after double-blinded administration of placebo (n= 7), vasopressin (0.3 U/min; n= 8) or vasopressin (0.3 U/min) plus nasal oxygen (4 L/min; n= 8). No significant effects on gastric mucosal haemodynamics and oxygenation were observed after placebo. In contrast, vasopressin and vasopressin plus oxygen induced a similar reduction in haemoglobin content (-26 ± 2 and -21 ± 4%, respectively P < 0.01) and laser Doppler signal (-23 ± 2 and -22 ± 2%, respectively, P < 0.01). Although each treatment induced a significant reduction in oxygen saturation (-21 ± 2 and -7 ± 1%, respectively P < 0.01), the effect was less pronounced in patients receiving the combination than in those receiving vasopressin alone (P < 0.01). These data suggest that vasopressin and vasopressin plus oxygen reduce gastric mucosal hyperaemia and that the oxygen supplement partially protects against gastric mucosal hypoxia during vasopressin infusion in cirrhotic patients with portal-hypertensive gastropathy.     

Do Sacral/Peripheral Lesions Contribute to Detrusor‐Sphincter Dyssynergia?

Objectives: While detrusor‐sphincter dyssynergia (DSD) occurs in conjunction with lesions between the brainstem and the sacral cord, it is not well known whether sacral/peripheral lesions contribute to DSD. We studied the relationship between DSD and sacral/peripheral lesions. Methods: One hundred and forty‐four patients with diverse neurologic etiologies underwent urodynamic study and analysis of motor unit potentials in the external sphincter muscles, 117 of whom were able to void during a urodynamic test. Sacral/peripheral lesion (SPL) is defined as neurogenic change in motor unit potentials. Detrusor overactivity (DO) is defined as involuntary detrusor contractions during the filling phase, which commonly occurs in lesions above the sacral cord. We considered DO as a putative indicator of supra‐sacral lesion. Results: DSD was found in 44 (30.6%), SPL in 71 (49.3%), and DO in 83 (57.6%) of 144 patients, respectively. The incidence of DSD was the same in the SPL positive group (31%) and the SPL negative group (30.1%). By contrast, within the subgroup of patients without DO, the incidence of DSD was significantly more common in the SPL positive group (41.4%) than in the SPL negative group (25.0%) (P < 0.05). In 53 of the SPL positive group who were able to void, postvoid residual >100 mL was more common in patients with DSD (not statistically significant). Conclusion: The results of the present study suggest that not only suprasacral pathology, but also sacral/peripheral lesions can produce DSD. In light of the previous reports, DSD might also result from partial lesions in peripheral branches of the sphincter circuit.     

Analysis of Electrophysiological Activity in Koch's Triangle Relevant to Ahlation of the Slow AV Nodal Pathway

Atrioventricuiar junctional reentrant tachycardia (AVfBT) is the most common form of paroxysmal regular supraventricular tachycardia. In patients with disabling, drug refractory AVJBT, catheter ablation has evolved rapidly from a last-resort treatment in the form of interruption of atrioventricular (AV) conduction to selective modification of AV nodal function as an ideal treatment. This article will focus on the frequently unappreciated electrophysiological activities recordable in man in Kach's triangle during ablation of the so-called slow pathway.     

Segment by Segment Linear Ablation with an Articulated Bilimb Catheter: Initial Experimental Results

Transcatheter radiofrequency (RF) ablation of atrial fibrillation or flutter requires the creation of linear lesions. However, conventional catheters are not predictably effective because of poor endocardial contact, and limited lesion size and penetration. The purpose of the study was to assess, in the right atrium, the efficacy and safety of a new catheter designed to create long myocardial tissue lesions using RF energy. The main characteristics of this 8 Fr deflectable RF ablation catheter were: (1) a perpendicularly contacting articulated bilimb electrodes ensuring stable and firm endocardial firm contact; and (2) an irrigated planar interface. Three different electrode prototypes were tested. Fourteen anesthetized sheep weighing 61 ± 7 kg underwent RF ablation in the right atrium using three incremental power levels (25 to 45, 50, 55 to 75 W) with the aim of creating fully transmural (FT) lesions, defined as continuous and complete epicardial and endocardial lesion imprints. The animals were euthanized 1 hour later for macroscopic and histologic examinations. Forty-three of the 80 right atrial lesions created, in smooth as well as in trabeculated areas, were FT. The percentage of FT lesions increased with the applied power from 37% with 25–45 W, to 49% with 50 W, and up to 86% for 55–75 W. In all but two cases, histologic examination showed no discontinuity between FT lesions produced by both limbs resulting in 19 coalescent linear lesions with an average size of 25 × 6 × 4 mm (length × width × depth). In situ bipolar electrograms after ablation in the FT group showed split potentials and/or a marked decrease in amplitude from 2.85 ± 1.79 to 0.33 ± 0.14 mV (P = 0.001) accompanied by near complete disappearance of unipolar electrograms. There was no perforation due to RF ablation. In conclusion, continuous and FT lesions can be achieved in various areas of sheep atria, including the trabecular right atrium, with a perpendicularly contacting bilimb electrode catheter. It represents a promising tool for catheter ablation of atrial fibrillation and flutter.     

Shortcut Link Between the Fast and Slow Pathways and the Mechanism of Cure in Atrioventricular Nodal Reentrant Tachycardia by Catheter Ablation

The mechanism of cure in AV nodal reentrant tachycardia (AVNRT) by catheter ablation has not been fully clarified. We hypothesized that disruption of a shortcut link between the fast and slow pathways is responsible for the elimination of tachycardia. Results: AVNRT was eliminated in 20 patients by catheter ablation. In five patients (25%; group 1) slow pathway conduction disappeared 1 week after ablation. In six patients (30%; group II), the effective refractory period of the slow pathway was prolonged by more than 50 ms (212 ± 81 ms vs 340 ± 81 ms; P < 0.05). In the remaining nine patients (45%; group III), there was no change in the refractory period (270 ± 65 ms vs 273 ± 74 ms), although tachycardia was not inducible. A shortcut link between the fast and slow pathways was examined by comparing the A-H intervals over the slow pathway during the tachycardia and during atrial pacing at the tachycardia cycle length. Prior to ablation, a shortcut link was assumed in 1 of group I patients, 2 of group II patients, and 8 of group III patients. Of the 9 patients in whom the slow pathway was not impaired after ablation (group III), 8 patients were found to have a shortcut link, while 8 of 11 patients with impairment of the slow pathway after ablation (groups I and II) had no shortcut link between the fast and slow pathways (P < 0.05). Conclusion: In patients with a shortcut link between the fast and slow pathways, slow pathway conduction itself does not need to be impaired to eliminate the AVNRT, whereas in patients without this shortcut link, slow pathway conduction must be impaired.     

Satisfactory remission achieved by PUVA therapy in a case of crisis-type adult T-cell leukaemia/lymphoma with generalized cutaneous leukaemic cell infiltration

We used PUVA therapy in a patient with crisis-type adult T-cell leukaemia/lymphoma and generalized cutaneous leukaemic cell infiltration. PUVA proved very effective in reducing leukaemic cells and in clearing the eruption. To understand the way in which PUVA produced a reduction in the number of leukaemic cells, we examined peripheral blood cells by light and electron microscopy. Light microscopy was of little help, but electron microscopy revealed that PUVA induced apoptosis-like changes in circulating leukaemic cells. This suggests that apoptosis-like changes in leukaemic cells might be the reason for the success of this treatment.     

Changes in risk factors for severe low-back pain among caregivers in care facilities in Japan from 2014 to 2018

In Japan, the practice of the no-lift policy, which states that care recipients should be lifted with care equipment rather than by human power, has been increasing since around 2014. The purpose of this study was to examine whether severe low back pain (LBP) risk factors in caregivers changed between 2014 and 2018. A questionnaire survey targeting administrators and caregivers working in care facilities for the elderly was conducted in 2014 and 2018. A total of 612 facilities and 2,712 caregivers responded to the questionnaires in 2014, and 504 facilities and 3,478 caregivers completed the questionnaires in 2018. The percentage of caregivers who experienced severe LBP did not differ significantly between 2014 (37.3%) and 2018 (38.3%). However, the number of facilities that introduced care equipment for transfer increased in 2018. Moreover, the number of participants who received training on care methods and using care equipment increased. Lifting a facility resident using human power and taking an unsuitable posture were associated with severe LBP in 2014, but only taking an unsuitable posture was associated with severe LBP in 2018. As taking an unsuitable posture remains to be a primary risk factor for severe LBP, it needs to be addressed in care facilities.