Myasthenia gravis concurrent with Parkinson's disease in a Spanish cohort. Causation or correlation?

BACKGROUND

Comorbidity between myasthenia gravis (MG) and other autoimmune diseases is well-documented. However, concurrent MG and Parkinson's disease (PD) have rarely been described. This concurrence has mostly been considered coincidental in cases reported to date.

MATERIAL/METHODS

We characterized patients with concurrent MG and PD within a cohort of 631 MG patients by gender, age, MGFA class, quantitative MG score at diagnosis, UPDRS score at diagnosis, and the DaTSCAN uptake pattern, to determine the frequency and the phenotype of individuals with these two concurrent entities. Meta-analysis of cases in the literature was used for comparison with our series.

RESULTS

Eighteen cases were identified in which the two diseases were concurrent. The major characteristics of the phenotype are male prevalence, late-onset MG, and frequent initial symptoms of dropped head and oculobulbar involvement. DAT confirmed reduced bilateral uptake in eleven patients and reduced unilateral uptake in the others.

CONCLUSIONS

To our knowledge, this is the largest reported series of concurrent MG and PD. This concurrence is more common than expected (2.85%). Either MG or PD may appear first. We found no iatrogenic relationship for the order of appearance. The overlapping of symptoms sometimes leads physicians to overlook the second disease, instead viewing it as a deterioration of the first. This study describes patients with well-documented diagnoses of both MG and PD, thus providing further indications of a shared etiology of these two diseases. Prospective studies including genetic, immunological, and environmental analysis are necessary to identify possible common pathogenic mechanisms.

Evidence of high compliance and fatigue in mask adherence in two mandates in Barcelona, Spain: a naturalistic observational study

OBJECTIVE

We investigated a possible pandemic fatigue effect, comparing adherence to compulsory mask use outdoors in Barcelona during the fourth and sixth waves of the pandemic.

STUDY DESIGN

We used naturalistic observation to determine the degree of pedestrians' compliance.

METHODS

We assessed mask use outdoors in a sample of pedestrians in Barcelona between 28 December 2021 and 9 February 2022 (during the sixth wave in Spain), and compared it with the fourth wave (which was between 5 April 2021 and 29 April 2021). Masks were compulsory in both periods.

RESULTS

The population studied amounted to 45,116 people (21,246 in the fourth wave and 23,870 in the sixth wave). In the sixth wave, only 67.3% wore a mask correctly, 18.6% did so incorrectly and 14.1% did not wear a mask, while the figures for the fourth wave were 78.2%, 16.3% and 5.5%, respectively (P = 0.001).

CONCLUSION

Our results suggest that adherence was high in the population studied, but with an evident fatigue effect when the two waves were compared, as the proportion of individuals wearing a mask correctly declined compared to the fourth wave. These results suggest that policymakers need guidance on adopting clear and enforceable guidelines during future mask mandates, assessing advantages and drawbacks in terms of the population's behavior to prevent the fatigue effect.

Abstract P5-10-11: Clinical significance of microRNA expression as a prognostic factor in early N+ breast cancer (BC)

Background: microRNAs (miRNAs) are small noncoding RNA molecules that post-transcriptionally regulate gene expression. In the present study, we describe miRNA expression in early node-positive BC and identify a 8-miRNA score that could contribute to prognosis assessment.

Methods: First, microarray analysis was performed using RNA samples extracted from primary breast cancer. The expression of miRNAs was analyzed by RT-qPCR using the TaqMan Arrays from Applied Biosystems. After a suitable normalization of the 677 miRNAs analyzed, 123 presented a good correlation between their levels of expression in frozen tissue and paraffin tissue. A supervised analysis was done in order to identify MIR that could predict relapse.

Results: 172 patients with node-positive chemotherapy-treated early BC were included in the present study. The median age at diagnosis was (53.7) years, 128 cases (74.4%) had positive estrogen receptor, and 163 patients (94,7%) received adjuvant chemotherapy. After a median follow up of 8,1 years, 71p (41.2%) relapsed. Supervised analyses identified 8 microRNAs (has miR-30e, miR-30a, miR-21, miR-210, miR-93, miR-150, miR-99b, miR-572) associated with higher risk of relapse (5 year PFS 50% vs 90%, HR 3.75, 95% CI 2.27–6.19) and with estimated overall survival (median not reached, HR 4.51, 95% CI 2.36–8.61). Interestingly, miRNAs defined 2 prognostic groups (high and low risk) regardless of type of adjuvant chemotherapy (with or without anthracyclines) and histological subtype (luminal A, B or triple negative).

Cells overexpressing fructose-2,6-bisphosphatase showed enhanced pentose phosphate pathway flux and resistance to oxidative stress

Changes in the content of fructose-2,6-bisphosphate, a modulator of glycolytic flux, also affect other metabolic fluxes such as the non-oxidative pentose phosphate pathway. Since this is the main source of precursors for biosynthesis in proliferating cells, PFK-2/FBPase-2 has been proposed as a potential target for neoplastic treatments. Here we provide evidence that cells with a low content of fructose-2,6-bisphosphate have a lower energy status than controls, but they are also less sensitive to oxidative stress. This feature is related to the activation of the oxidative branch of the pentose phosphate pathway and the increased production of NADPH.

Lymphocytosis in a patient with malignant fibrous histiocytoma

Malignant fibrous histiocytoma is an uncommon soft-tissue sarcoma. Patients with malignant fibrous histiocytoma may present with unusual clinical findings and an apparent association with malignant hematopoietic disease has been reported. We describe a patient in whom a diagnosis of chronic lymphocytic leukemia was made simultaneously with discovery of a large, retroperitoneal malignant fibrous histiocytoma. Following surgical debulking of the tumor, the patient's blood and bone marrow findings returned to normal.