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In this review, we summarize the current knowledge on sex differences in dementia with Lewy bodies (DLB) relating to epidemiology, clinical features, neuropathology, biomarkers, disease progression, and caregiving. While many studies show a higher DLB prevalence in men, this finding is inconsistent and varies by study approach. Visual hallucinations may be more common and occur earlier in women with DLB, whereas REM sleep behavior disorder may be more common and occur earlier in men. Several studies report a higher frequency of parkinsonism in men with DLB, while the frequency of fluctuations appears similar between sexes. Women tend to be older, have greater cognitive impairment at their initial visit, and are delayed in meeting DLB criteria compared to men. Women are also more likely to have Lewy body disease with co-existing AD-related pathology than so-called pure Lewy body disease, while men may present with either. Research is mixed regarding the impact of sex on DLB progression. Biomarker and treatment research assessing for sex differences is lacking. Women provide the majority of caregiving in DLB but how this affects the caregiving experience is uncertain. Gaining a better understanding of sex differences will be instrumental in aiding future development of sex-specific strategies in DLB for early diagnosis, care, and drug development.

INTRODUCTION: We examined the progression of extrapyramidal symptoms and signs in autopsy‐confirmed dementia with Lewy bodies (DLB), Parkinson's disease dementia (PDD), and Alzheimer's disease dementia (AD). METHODS: Longitudinal data were obtained from Arizona Study of Aging and Neurodegenerative Disease, with PDD (n = 98), AD (n = 47) and DLB (n = 48) further sub‐grouped as with or without parkinsonism (DLB+ and DLB−). Within‐group Unified Parkinson's Disease Rating Scale (UPDRS) ‐II and UPDRS‐III trajectories were analyzed using non‐linear mixed effects models. RESULTS: In DLB, 65.6% had parkinsonism. Baseline UPDRS‐II and III scores (off‐stage) were highest (P < 0.001) for PDD (mean ± SD 14.3 ± 7.8 and 27.4 ± 16.3), followed by DLB+ (6.0 ± 8.8 and 17.2 ± 17.1), DLB− (1.1 ± 1.3 and 3.3 ± 5.5) and AD (3.2 ± 6.1 and 8.2 ± 13.6). Compared to PDD, the DLB+ group had faster UPDRS‐III progression over 8‐years (Cohen's‐d range 0.98 to 2.79, P < 0.001), driven by gait (P < 0.001) and limb bradykinesia (P = 0.02) subscales. DISCUSSION: Motor deficits progress faster in DLB+ than PDD, providing insights about expected changes in motor function. Highlights: Dementia with Lewy bodies has faster motor progression than Parkinson's disease dementiaLinear and non‐linear mixed modeling analysis of longitudinal data was utilizedFindings have implications for clinical prognostication and trial design [ABSTRACT FROM AUTHOR]

Hypocapnia and hypercapnia constrict and relax airway smooth muscle, respectively, through pH- and calcium ([Ca.sup.2+])-mediated mechanisms. In this study we explore a potential role for the airway epithelium in these responses to carbon dioxide (C[O.sub.2]). Contractile and relaxant responses of isolated rat bronchial rings were measured under hypocapnic, eucapnic, and hypercapnic conditions. Substance P was added to methacholine precontracted bronchial rings with and without epithelium. The role of [Ca.sup.2+] was assessed using [Ca.sup.2+]-free solutions and a [Ca.sup.2+] channel blocker, nifedipine. The effects of pH were assessed in solutions with HEPES buffer. Hypocapnic challenge increased the organ bath's pH and increased bronchial smooth muscle resting tension. This effect was abolished with HEPES buffer and partially inhibited by nifedipine. Hypocapnic conditions suppressed substance P-induced epithelium-dependent relaxation, whereas hypercapnia augmented the response. The epithelial hypocapnic effect was pH dependent, whereas the hypercapnic effect was pH independent. C[O.sub.2] had no effect on the epithelial independent smooth muscle agonists methacholine and isoproterenol. In conclusion our data indicate that, in addition to the effects of pH and [Ca.sup.2+], C[O.sub.2] affects airway smooth muscle by a pH-independent, epithelium-mediated mechanism. These findings could potentially lead to new treatments for asthma involving C[O.sub.2]-sensing receptors in the airways. Key words: asthma, hypercapnia, hypocapnia, airway smooth muscle, carbon dioxide, pH, calcium channel, epithelium, substance P. L'hypocapnie et l'hypercapnie provoquent la contraction et la relaxation du muscle lisse bronchique respectivement, par des mecanismes vehicules par le pH et le calcium ([Ca.sup.2+]). Dans la presente etude, nous examinons si l'epithelium bronchique joue un role dans la contraction et la relaxation induite par le dioxyde de carbone (C[O.sub.2]). Nous avons mesure les reponses d' anneaux bronchiques isoles de rats dans des conditions d' hypocapnie, de normocapnie et d' hypercapnie. Nous avons ajoute de la substance P aux anneaux bronchiques precontractes par la metacholine, en absence et en presence d'epithelium. Nous avons evalue le role du [Ca.sup.2+] en utilisant des solutions sans [Ca.sup.2+] et un bloqueur de canaux calciques, nifedipine. Nous avons evalue les effets du pH dans des solutions tampon HEPES. L'epreuve hypocapnique a augmente le pH du bain d'organes ainsi que la tension de repos du muscle lisse bronchique. Le tampon HEPES a supprime cet effet, et la nifedipine l' a partiellement inhibe. L' hypocapnie a supprime la relaxation dependante de l' epithelium induite par la substance P, alors que l' hypercapnie l' a augmentee. L' effet hypocapnique epithelial a ete dependant du pH, alors que l' effet hypercapnique a ete independant de celui-ci. Le C[O.sub.2] n'a pas eu d'effet sur les agonistes du muscle lisse independant de l'epithelium, metacholine et isoproterenol. Nos resultats indiquent que le C[O.sub.2] influe sur le muscle lisse bronchique par un mecanisme, vehicule par l'epithelium, independant du pH. Ces resultats pourraient mener a l'elaboration de nouveaux traitements de l' asthme impliquant les recepteurs sensibles au C[O.sub.2] dans les bronches. Mots-cles : asthme, hypercapnie, hypocapnie, muscle lisse bronchique, dioxyde de carbone, canal calcique, epithelium, substance P. [Traduit par la Redaction], Introduction Dysfunctional breathing in asthma is characterized by hyperventilation and hypocapnia (Thomas et al. 2001). There are several reports that hyperventilation may precipitate (Demeter and Cordasco 1986; Han et al. [...]

Introduction: We examined the temporal sequence of the core features in probable dementia with Lewy bodies (DLB). Methods: In 488 patients with probable DLB, the onset of each core feature and time to diagnosis was determined for men and women, and a pathologic subgroup (n = 209). Results: REM sleep behavior disorder (RBD) developed before the other core features in men and women. Men were more likely to have RBD and were diagnosed with probable DLB earlier than women. Visual hallucinations developed after the other core features in men, but in women, they appeared earlier and concurrently with fluctuations and parkinsonism. Women were older and more cognitively impaired at first visit, were less likely to have RBD, more likely to be diagnosed with probable DLB later than men, and more likely to have neocortical tangles. Discussion: An earlier latency to probable DLB was associated with men, RBD, and Lewy body disease without neocortical tangles. [ABSTRACT FROM AUTHOR]

Background: REM Sleep Behavior Disorder (RBD) is a prodromal marker of α‐synucleinopathies with no standardized tool for assessing severity in clinical or research practice. RBD severity may have implications in measuring risk of phenoconversion, monitoring response to treatment and clinical trial design. This study assessed the validity of the RBD symptom severity scale (RBDSSS) and its correlation to the clinical global impression of severity (CGI‐S) in a cohort of participants enrolled in the North American Prodromal Synucleinopathy (NAPS) Consortium. Method: Participants and their bedpartners enrolled in the NAPS cohort filled out an 8‐item questionnaire, developed by the International RBD Study Group, assessing frequency and severity of dreams, vocalizations, movements, and injuries associated with RBD, with higher scores indicating more severe symptoms. The CGI‐S is a 7‐point scale ranging from normal (1) to most severely ill (7) and was completed by a clinician based on an independent interview with the participant ± their bedpartners. Total scores for participant (RBDSSS‐PT) and bed partner (RBDSSS‐BP) questionnaires were derived by multiplying frequency and severity scores for each feature, then summing the products for possible maximum scores of 54 and 38 respectively. Result: This cohort (n = 212) was predominantly male (82.5%) with a mean ± SE age of 65.16 ± 1.46 years. The median (interquartile range) for RBDSSS‐PT, RBDSSS‐BP and CGI‐S was 11 (4‐17), 8 (4‐14.3) and 3 (3‐4), respectively. Spearman's rank correlation coefficients (rs) were as follows: RBDSSS‐PT vs. RBDSSS‐BP, rs = 0.579; RBDSSS‐PT vs. CGI‐S, rs = 0.642; RBDSSS‐BP vs. CGI‐S, rs = 0.487 (all P<0.0001). RBDSSS‐BP scores were significantly lower in women (6 vs. 9, Chi‐Square p = 0.009) while there were no differences in RBDSSS‐PT scores by sex. (9 vs. 11, p = 0.473). Conclusion: A moderate correlation was observed between RBDSSS‐PT and RBDSSS‐BP suggesting good construct validity for the scale. CGI‐S correlated most with RBDSSS‐PT and had a weaker association with RBDSSS‐BP. Women had lower severity scores as reported by bed partners unlike their self‐reported scores, indicating possible sex differences in perceived RBD severity. [ABSTRACT FROM AUTHOR]

The article discusses the results of a study that examined the cotton aphid, Aphis gossypii and its host races in asexual populations. The study showed distinct host races behavior of genotypes living in the wild plants of taro, Colocasia esculenta and brinjal, Solanum torvum. It noted the poor success rates of colonization after reciprocal host transfers with clones of Aphis gossypii from wild taro partly surviving in the first generation when transferred to brinjal.

In recent years, proposals have been advanced to redefine or reclassify Lewy body disorders by merging the long-established entities of Parkinson's disease (PD), Parkinson's disease dementia (PDD) and dementia with Lewy bodies (DLB). These proposals reject the International DLB Consortium classification system that has evolved over three decades of consensus collaborations between neurologists, neuropsychologists and neuropathologists. While the Consortium's "one year rule" for separating PD and DLB has been criticized as arbitrary, it has been a pragmatic and effective tool for splitting the continuum between the two entities. In addition to the decades of literature supporting the non-homogeneity of PD and DLB, it has become increasingly apparent that Lewy body disorders may fundamentally differ in their etiology. Most PD subjects, as well as most clinically-presenting DLB subjects, might best be classified as having a "primary synucleinopathy" while most clinically-unidentified DLB subjects, who also have concurrent neuropathology-criteria AD (AD/DLB), as well as those with neuropathological AD and amygdala-predominant LBD insufficient for a DLB diagnosis, may best be classified as having a "secondary synucleinopathy. Importantly, the DLB Consortium recognized the importance of comorbid AD pathology by defining "Low", "Intermediate" and "High" subdivisions of DLB based on the relative brain stages of both Lewy body and AD pathology. If the one-year rule for separating PD from DLB, and for then dividing DLB into subtypes based on the presence and severity of comorbid AD pathology, is effective, then the divided groups should statistically differ in important ways. In this study we used the comprehensive clinicopathological database of the Arizona Study of Aging and Neurodegenerative Disorders (AZSAND) to empirically test this hypothesis. Furthermore, we used multivariable statistical models to test the hypothesis that comorbid AD neuropathology is a major predictor of the presence and severity of postmortem Lewy synucleinopathy. The results confirm the clinicopathological heterogeneity of Lewy body disorders as well as the profound influence of comorbid AD pathology.