Two flares of Still’s disease after two doses of the ChAdOx1 vaccine

Clinical Rheumatology - We report the case of an 18-year-old male with Still’s disease for the last 3 years, in remission, who developed two flares of his disease after receiving two...     

Pure neuritic leprosy in India: an appraisal

BACKGROUND: Pure neuritic leprosy (PNL) constitutes a significant proportion of all cases in India, however, this form of disease has not been fully recognized and investigated and there is little information in the existing literature. OBJECTIVE: To study the epidemiological characteristics of PNL in India. MATERIALS AND METHODS: A retrospective analysis of leprosy clinic records for the period 1993 to 2003 was undertaken. Detailed demographic profiles and clinical findings were noted from the predesigned clinic proforma. A slit-skin smear for acid-fast baclli (AFB) was done in all cases from the area of sensory loss. A skin biopsy was done from the area of sensory impairment to study histopathological changes. Further investigations such as nerve conduction velocity studies (NCV), fine needle aspiration cytology (FNAC), or nerve biopsy (superficial nerve twigs) were done if indicated in patients whenever there was difficulty in clinical diagnosis. RESULTS: Of the total 1542 leprosy patients seen over this period, 65 (4.2%) had PNL. Males were more commonly affected than females (2.6:1.). The majority of patients 40/65(61.5%) were aged between 15 and 35 yrs. Predominant presenting symptoms were paresthesia, pain, sensory/motor deficit, and trophic changes. A majority of the patients 39/65 (60.0%) presented with involvement of 2 or more nerves in the same extremity. Mononeuritis was seen in 26 (40%) patients. The nerves most often involved were the right ulnar nerve in the upper extremity, and the right common peroneal nerve in the lower limb. In general, the nerves of the upper extremity were more commonly involved than in the lower limbs (67 vs. 55). Motor deformities such as claw hand and foot drop were present in 13/75 (20%) and 7/65 (10.8%) patients, respectively. Slit-skin smears were negative in all patients, and skin histopathology from the area of sensory loss revealed non-specific inflammation in the dermis in a majority of patients, with perineural inflammation in a few. All patients were treated with multi-drug therapy (MDT); patients with >/=2 peripheral nerve trunk involvements were treated with WHO MDT MB regimen, while others were administered WHO MDT PB regimen. Follow-up for up to 2 yrs was available in only 32/65 (49.2%) patients, none of whom developed any skin lesions during this period. CONCLUSION: PNL is a distinct subset of disease frequently seen in India. There is need to pay more attention to this form of leprosy and diagnose and treat patients earlier to prevent deformities and sequelae of nerve damage.     

Comparison of lesion sizes produced by cryoablation and open irrigation radiofrequency ablation catheters

Introduction: The relative lesion sizes created by large electrode cryoablation catheter and irrigated radiofrequency (RF) ablation are not known. The purpose of this study was to directly compare lesion sizes created by cryoablation and irrigated RF under controlled conditions.
Methods and Results : Ablation lesions were created in freshly harvested porcine left ventricular myocardium in a blood-filled tissue bath using an 8-mm-tip cryoablation catheter and a 3.5-mm-tip open-irrigated RF ablation catheter. Lesions were created under all permutations of the following conditions: electrode orientation vertical (perpendicular) or horizontal (parallel) to the tissue, electrode contact pressure at 6 or 20 g, and blood flow at 0.2 or 0.4 m/s over the electrode-tissue interface. The largest lesion volumes created with cryoablation were 961 ± 103 mm³, compared with the largest lesions volumes created with RF of 680 ± 48 mm³ (P < 0.001). The 3-way interactions among electrode orientation, contact pressure, and superfusate blood velocity accounted for the variation in lesion volumes for both catheters (both r²= 0.97, both P < 0.0001). The greater contact pressure increased lesion size for both cryoablation and RF. For cryoablation, lesion sizes were increased by the horizontal orientation and by the lower blood flow velocity. For open-irrigated RF, lesion sizes were significantly reduced by the horizontal orientation, however.
Conclusions : Depending on conditions of electrode orientation, contact pressure, and blood velocity, either 8-mm-tip cryoablation or open-irrigated RF may produce the larger lesion volumes. Open-irrigated RF lesion sizes are reduced in the horizontal catheter orientation.     

Androgen-repressed phenotype in human prostate cancer

An androgen-repressed human prostate cancer cell line, ARCaP, was established and characterized. This cell line was derived from the ascites fluid of a patient with advanced metastatic disease. In contrast to the behavior of androgen-dependent LNCaP and its androgen-independent C4-2 subline, androgen and estrogen suppress the growth of ARCaP cells in a dose-dependent manner in vivo and in vitro. ARCaP is tumorigenic and highly metastatic. It metastasizes to the lymph node, lung, pancreas, liver, kidney, and bone, and forms ascites fluid in athymic hosts. ARCaP cells express low levels of androgen receptor mRNA and prostate-specific antigen mRNA and protein. Immunohistochemical staining shows that ARCaP cells stain intensely for epidermal growth factor receptor, c-erb B2/neu, and c-erb B3. Staining is negative for chromogranin A and positive for bombesin, serotonin, neuron-specific enolase, and the c-met protooncogene (a hepatic growth factor/scatter factor receptor). ARCaP cells also secrete high levels of gelatinase A and B and some stromelysin, which suggests that this cell line may contain markers representing invasive adenocarcinoma with selective neuronendocrine phenotypes. Along with its repression of growth, androgen is also found to repress the expression of prostate-specific antigen in ARCaP cells as detected by a prostate-specific antigen promoter–β-galactosidase reporter assay. Our results suggest that the androgen-repressed state may be central to prostate cancer progression and that advanced prostate cancer can progress from an androgen-independent to an androgen-repressed state.     

Maldistribution of pulmonary blood flow in patients after the Fontan operation is associated with worse exercise capacity

Background

Maldistribution of pulmonary artery blood flow (MPBF) is a potential complication in patients who have undergone single ventricle palliation culminating in the Fontan procedure. Cardiovascular magnetic resonance (CMR) is the best modality that can evaluate MPBF in this population. The purpose of this study is to identify the prevalence and associations of MPBF and to determine the impact of MPBF on exercise capacity after the Fontan operation.

Methods

This retrospective single-center study included all patients after Fontan operation who had maximal cardiopulmonary exercise test (CPET) and CMR with flow measurements of the branch pulmonary arteries. MPBF was defined as >?20% difference in branch pulmonary artery flow. Exercise capacity was measured as percent of predicted oxygen consumption at peak exercise (% predicted VO₂). Linear and logistic regression models were used to determine univariate and multivariable predictors of exercise capacity and correlates of MPBF, respectively.

Results

A total of 147 patients who had CMR between 1999 and 2017 were included (median age at CMR 21.8?years [interquartile range (IQR) 16.5–30.6]) and the median time between CMR and CPET was 2.8?months [IQR 0–13.8]. Fifty-three patients (36%) had MPBF (95% CI 29–45%). The mean % predicted VO₂ was 63?±?16%. Patients with MPBF had lower mean % predicted VO₂ compared to patients without MPBF (60?±?14% versus 65?±?16%, p?=?0.04). On multivariable analysis, a lower % predicted VO₂ was independently associated with longer time since Fontan, higher ventricular mass-to-volume ratio, and MPBF. On multivariable analysis, only compression of the branch pulmonary arteries by the ascending aorta or aortic root was associated with MPBF (OR 6.5, 95% CI 5.6–7.4, p?<?0.001).

Conclusion

In patients after the Fontan operation, MPBF is common and is independently associated with lower exercise capacity. MPBF was most likely to be caused by pulmonary artery compression by the aortic root or the ascending aorta. This study identifies MPBF as an important risk factor and as a potential target for therapeutic interventions in this fragile patient population.

     

ADARRI: a novel method to detect spurious R-peaks in the electrocardiogram for heart rate variability analysis in the intensive care unit

We developed a simple and fully automated method for detecting artifacts in the R-R interval (RRI) time series of the ECG that is tailored to the intensive care unit (ICU) setting. From ECG recordings of 50 adult ICU-subjects we selected 60 epochs with valid R-peak detections and 60 epochs containing artifacts leading to missed or false positive R-peak detections. Next, we calculated the absolute value of the difference between two adjacent RRIs (adRRI), and obtained the empirical probability distributions of adRRI values for valid R-peaks and artifacts. From these, we calculated an optimal threshold for separating adRRI values arising from artifact versus non-artefactual data. We compared the performance of our method with the methods of Berntson and Clifford on the same data. We identified 257,458 R-peak detections, of which 235,644 (91.5%) were true detections and 21,814 (8.5%) arose from artifacts. Our method showed superior performance for detecting artifacts with sensitivity 100%, specificity 99%, precision 99%, positive likelihood ratio of 100 and negative likelihood ratio <0.001 compared to Berntson’s and Clifford’s method with a sensitivity, specificity, precision and positive and negative likelihood ratio of 99%, 78%, 82%, 4.5, 0.013 for Berntson’s method and 55%, 98%, 96%, 27.5, 0.460 for Clifford’s method, respectively. A novel algorithm using a patient-independent threshold derived from the distribution of adRRI values in ICU ECG data identifies artifacts accurately, and outperforms two other methods in common use. Furthermore, the threshold was calculated based on real data from critically ill patients and the algorithm is easy to implement.     

Hierarchical CdMoO4 nanowire–graphene composite for photocatalytic hydrogen generation under natural sunlight

Herein, a facile in situ solvothermal technique for the synthesis of a CdMoO₄/graphene composite photocatalyst is reported. Graphene oxide (GO) was synthesised by an improved Hummers'' method and was further used for the in situ synthesis of graphene via GO reduction and the formation of a CdMoO₄ nanowire/graphene composite. The structural phase formation of tetragonal CdMoO₄ was confirmed from X-ray diffraction measurements. The small nanoparticle assembled nanowires, prismatic microsphere morphology and crystalline nature of the synthesized material were investigated using field emission scanning electron microscopy (FESEM) and transmission electron microscopy (TEM). Due to its unique morphology and stability, the CdMoO₄/graphene composite was used as a photocatalyst for H₂O splitting. In comparison to pristine CdMoO₄, the CdMoO₄/graphene composite showed the best hydrogen evolution rate, i.e. 3624 μmole h⁻¹ g⁻¹, with an apparent quantum yield of 30.5%. The CdMoO₄/graphene composite has a higher photocatalytic activity due to the inhibition of charge carrier recombination. H₂ production measurements showed that the ternary semiconductor/graphene composite has enhanced photocatalytic activity for H₂ generation.

Herein, a facile in situ solvothermal technique for the synthesis of a CdMoO₄/graphene composite photocatalyst for hydrogen generation under natural solar light.