Central Nervous System Mechanisms of Nausea in Gastroparesis: An fMRI-Based Case-Control Study

BACKGROUND/AIMS

Nausea is a major complaint of gastroparesis (GP), and the pathophysiology of this condition is poorly understood. Therefore, this study utilized fMRI to investigate the possible central nervous system (CNS) mechanisms of nausea in 10 GP patients versus 8 healthy controls (HCs).

METHODS

Nausea severity was assessed on a 0-10 scale and presented as mean ± SD. Nausea was increased from baseline utilizing up to 30 min of visual stimulation (VS). Functional network connectivity was measured with fMRI at baseline and after 30 min of VS. fMRI data were preprocessed using statistical parametric mapping software. Thirty-four independent components were identified as meaningful resting-state networks (RSNs) by group independent component analysis. The Functional Network Connectivity (FNC) among 5 RSNs considered important in CNS nausea mechanisms was calculated as the Pearson's pairwise correlation.

RESULTS

Baseline nausea score in GP patients was 2.7 ± 2.0 and increased to 7.0 ± 1.5 after stimulation (P < 0.01). In HCs nausea scores did not increase from baseline after stimulus (0.3 ± 0.5). When comparing GP patients to HCs after VS, a significant reduction (P < 0.001) in bilateral insula network connectivity compared to the right insula network was detected. No significant differences in connectivity were noted among the other RSNs. Additionally, the average gray matter volume was non-significantly reduced in the insula in GP patients compared to HC.

CONCLUSIONS

The insula connectivity network is impaired in nauseated GP patients. This phenomenon could explain the susceptibility of GP patients to nausea or may have resulted from a state of chronic nausea.

Data on the association between age at natural menopause and physical function in older women from the International Mobility in Aging Study (IMIAS)

Women experience worse physical function and greater physical decline than men at similar ages. These sex differences are heterogeneous across settings and plausibly linked to gender inequality, with evidence of increasing disadvantage for women in increasingly iniquitous societies. As described in “Age at natural menopause and physical function in older women from Albania, Brazil, Colombia and Canada: A life-course perspective” [Velez et al., 2019] we assessed the association between age at natural menopause (ANM) and objectives markers of physical function (i.e., gait speed and grip strength) in older women from the International Mobility in Aging Study (IMIAS). For all sites combined, women with ANM ≥55 had higher gait speed than those with ANM 50–54. Women with ANM <40 had significantly lower grip strength compared with all other groups. In this article, we describe the region-specific associations between ANM, gait speed, and grip strength in 775 women aged 65–74, from the Southeastern European site (Tirana, Albania), Latin American sites (Manizales, Colombia and Natal, Brazil), and Canadian sites (Kingston, Ontario and Saint-Hyacinthe, Quebec). In region-specific analyses, ANM was associated with grip strength in Albania and Latin America and with gait speed in Albania only. No associations were observed in Canada.

Age at natural menopause and physical function in older women from Albania, Brazil, Colombia and Canada: A life-course perspective

OBJECTIVE

Grip strength and gait speed are objective measures of physical function, which in turn is an indicator of biological aging. We evaluate the association between age at natural menopause (ANM) and physical functioning in a sample of postmenopausal women drawn from the International Mobility in Aging Study (IMIAS).

STUDY DESIGN

Retrospective cohort study of 775 women aged 65-74, from Albania, Brazil, Colombia and Canada, who had experienced natural menopause.

MAIN OUTCOME MEASURES

Gait speed and grip strength were obtained following standardized protocols. The association between self-reported ANM (<40, 40-44, 45-49, 50-54 and ≥55) and gait speed (m/s) and grip strength (kg) was assessed by linear regression analyses adjusting for several life-course economic and reproductive exposures, height, BMI and smoking.

RESULTS

Overall, women with ANM ≥ 55 had higher gait speed than those with ANM 50-54 (β = 0.05; 95%CI: 0.01, 0.10). Women with ANM < 40 had significantly lower grip strength compared with all other groups (β= -2.58; 95%CI: -4.43, -0.74). In region-specific analyses, ANM was associated with grip strength in Albania and Latin America and with gait speed in Albania only. No associations were observed in Canada.

CONCLUSIONS

ANM is associated with markers of physical functioning. Differences across study sites suggest that women in socially disadvantaged areas may reach menopause with different physiological reserves than those from more advantaged settings, leading to greater losses in muscle strength in postmenopausal years. More work comparing distinct populations is needed to better understand the underlying mechanisms.

The Long-Term Efficacy and Safety of Pyloroplasty Combined with Gastric Electrical Stimulation Therapy in Gastroparesis

INTRODUCTION

Gastroparesis is delayed gastric emptying without mechanical obstruction. Symptomatic improvement can be 50-60% with gastric electrical stimulation. To address delayed gastric emptying, pyloroplasty was added. This study examines the long-term efficacy and safety of simultaneous gastric electrical stimulator implantation and pyloroplasty.

METHODS

In this prospective single-arm trial conducted from 2012 to 2015, 27 [23 females; mean age 43 (22-63)] gastroparesis patients who underwent simultaneous gastric electrical stimulator implantation with Heineke-Mikulicz pyloroplasty were studied. Six (25%) underwent simultaneous robot-assisted pyloroplasty and gastric electrical stimulator implantation. Diagnosis of gastroparesis was based on the 4-h gastric emptying test defined as >60% retention of isotope at 2 h and >10% at 4 h. Total symptom scores assessing severity of nausea, early satiety, bloating, vomiting, post-prandial fullness, and epigastric pain were obtained at baseline and at follow-up visits, ranging from 3 to 38 months (mean: 17).

RESULTS

Follow-up data from 24 patients were available for analysis. There was 71% improvement in total symptom score on follow-up. Mean retention decreased by 29.6 and 48.7% at 2 and 4 h and gastric emptying was normalized in 60%. There were no post-surgical complications.

CONCLUSIONS

Combination of gastric electrical stimulator and pyloroplasty significantly accelerated gastric emptying and improved gastroparesis symptoms. Combining these two surgical therapies improves both subjective and objective endpoints in drug refractory gastroparesis.

Factors associated with hypertension prevalence, awareness, treatment and control among participants in the International Mobility in Aging Study (IMIAS)

The aim of this study is to assess the factors associated with hypertension prevalence, awareness, treatment, and control, in the elderly populations of the International Mobility in Aging Study (IMIAS). Approximately 200 men and 200 women aged 65-74 years were recruited at each site (n=1995) during IMIAS' 2012 baseline survey at five cities: Kingston (Canada), Saint-Hyacinthe (Canada), Tirana (Albania), Manizales (Colombia) and Natal (Brazil). Blood pressure and anthropometric measurements were taken at participants' homes. Hypertension prevalence ranged from 53.4% in Saint-Hyacinthe to 83.5% in Tirana. Diabetes and obesity were identified as risk factors in all cities. More than two-thirds of hypertensive participants were aware of their condition (from 67.3% in Saint-Hyacinthe to 85.4% in Tirana); women were more aware than men. Awareness was positively associated with diabetes in Kingston, Manizales and Natal. Though most of those aware of their hypertensive condition were being treated pharmacologically, associations between awareness and physical activity and refraining from smoking were weak. Control among treated hypertensive participants was low, especially in Tirana and Natal. Diabetes and physical inactivity were associated with poor hypertension control. Hypertension is common in the older populations of IMIAS. Diabetes is strongly associated with hypertension prevalence, awareness and lack of control of hypertension. The fact that awareness is not strongly associated with healthy behaviours suggests that antihypertensive medication is not accompanied by non-pharmacological therapies. Improved health behaviours could strengthen hypertension control. Efforts should be made to increase men's awareness of hypertension. Hypertension control in diabetic patients is a challenge.

Applicability of the MoCA-S test in populations with little education in Colombia

OBJECTIVES

The objectives of this study were to report on the use of the Spanish version of the Montreal Cognitive Assessment (MoCA-S) as cognitive screening tool in a population aged 65 to 74 years in the Andes Mountains of Colombia, assessing the influence of education, and to examine its test-retest reliability.

METHODS

We performed a cross-sectional study of 150 subjects aged 65 to 74 years recruited from older community social centers in Manizales, Colombia. The Leganes Cognitive Test (LCT), a cognitive screening test for populations with low education, was used to exclude those who were likely to have dementia. The associations between the MoCA total score and cognitive domains and education were examined in the total sample and in those likely free of dementia. MoCA-S test-retest reliability was estimated by the intraclass correlation coefficient (ICC) between two measurements taken 7 days apart.

RESULTS

Participants had low levels of formal education (mean years of schooling, 4.8). According to the LCT, the proportion of people screening positive for dementia was 16% (n = 24). The mean MoCA-S scores were 16.1/30 among illiterate subjects, 18.2/30 among those with incomplete primary school, and 20.3/30 among those with complete primary school (p < 0.001). Errors were frequent in the cube and clock drawing, attention-serial subtraction, verbal fluency, and abstraction. Test-retest reliability was high, ICC = 0.86, 95% CI (0.76-0.93).

CONCLUSION

The MoCA-S has high reliability in low-educated older Colombians, but scores were strongly dependent on years of education. Social and cultural factors must be considered when interpreting MoCA-S given the high error rates on items that depend on the ability to read and write and on culture.

Perceptions about Hearing Aids from Elderly Non-Users: A Bicultural Point of View (Italy and USA)

Perceptions about hearing aids can vary across people of different cultural backgrounds depending upon beliefs, healthcare policies, education, etc[...]

Taxane-specific monoclonal antibodies: measurement of taxol, baccatin III, and "total taxanes" in Taxus brevifolia extracts by enzyme immunoassay

Three monoclonal antibodies with either specificity to taxol or baccatin III, or cross-reactivity with several common taxanes have been prepared and used to develop sensitive competitive-inhibition enzyme immunoassays. The hybridomas producing these monoclonal antibodies were obtained by fusing P3X63Ag8.653 plasmacytoma cells and splenocytes from mice hyperimmunized with keyhole limpet hemocyanin-7-succinyltaxol or -7-succinylbaccatin III conjugates. Direct and indirect competitive inhibition enzyme immunoassays were developed with these monoclonal antibodies and microtiter plates coated with bovine serum albumin conjugates of the complementary hapten. Detection limits for the direct competitive inhibition enzyme immunoassays, conducted in buffer containing 10% MeOH, were 0.6 nM taxol for 3C6 (anti-taxol); 1.1 nM baccatin III for 3H5 (anti-baccatin III); and 0.6 nM taxol or baccatin III for 8A10 (anti-taxane). The immunoassays accurately detected taxol, baccatin III, and "total taxanes" in crude MeOH extracts of Taxus brevifolia bark and in hplc fractions of these extracts.

Determination of taxanes in Taxus brevifolia extracts by tandem mass spectrometry and high-performance liquid chromatography

A tandem mass spectrometric (ms/ms) method using desorption chemical ionization is described for the quantitation of taxol [1], cephalomannine [2], and baccatin III [3] found in Taxus brevifolia bark and needle extracts. A parent ion scan was used to simultaneously determine the weight percentages of 1-3 in bark and needle samples by the method of standard addition. In an alternative experiment, the concentration of 1 in the same samples was determined by ms/ms using trideuterated 10-acetyltaxol [7a] as an internal standard. High-performance liquid chromatography (hplc) was also used to determine the weight percentages of 1-3 in the same T. brevifolia bark and needle extracts with an external standard. The ms/ms method of quantitation by internal standard is the best overall method of analysis examined. With this method, 1 was quantitated in the T. brevifolia extracts at the low picomole level with a relative standard deviation of 17% or better for all samples analyzed with an analysis time of less than five min per sample. The precision, level of quantitation, and speed of analysis of the three methods of taxane quantitation are compared.

Novel soluble, high-affinity gastrin-releasing peptide binding proteins in Swiss 3T3 fibroblasts

Swiss 3T3 cells contained substantial amounts of soluble and specific [125I]GRP binders. Like the membrane-associated GRP receptor, they were of high affinity, saturable, bound to GRP(14-27) affinity gels, and exhibited specificity for GRP(14-27) binding. They differed in that acid or freezing destroyed specific binding, specific binding exhibited different time and temperature effects, no detergent was required for their solubilization, ammonium sulfate fractionation yielded different profiles, the M(rs) were lower, GRP(1-16) also blocked binding, and a polyclonal anti-GRP receptor antiserum did not bind on Western blots. The isolated, soluble GRP binding protein(s) rapidly degraded [125I]GRP. These soluble GRP binding proteins may play a role in the regulation of the mitogenic effects of GRP on these cells.