Mice deficient for FgfR2-IIIb were generated by placing translational stop codons and an IRES-LacZ cassette into exon IIIb of FgfR2. Expression of the alternatively spliced receptor isoform, FgfR2-IIIc, was not affected in mice deficient for the IIIb isoform. FgfR2-IIIb(-/-) (lac)(Z) mice survive to term but show dysgenesis of the kidneys, salivary glands, adrenal glands, thymus, pancreas, skin, otic vesicles, glandular stomach, and hair follicles, and agenesis of the lungs, anterior pituitary, thyroid, teeth, and limbs. Detailed analysis of limb development revealed an essential role for FgfR2-IIIb in maintaining the AER. Its absence did not prevent expression of Fgf8, Fgf10, Bmp4, and Msx1, but did prevent induction of Shh and Fgf4, indicating that they are downstream targets of FgfR2-IIIb activation. In the absence of FgfR2-IIIb, extensive apoptosis of the limb bud ectoderm and mesenchyme occurs between E10 and E10.5, providing evidence that Fgfs act primarily as survival factors. We propose that FgfR2-IIIb is not required for limb bud initiation, but is essential for its maintenance and growth.

Mice deficient for fibroblast growth factor (Fgf)R2-IIIb show a block in thymic growth after embryonic day 12.5, a stage that just precedes its detection in thymic epithelial cells. Fgf7 and Fgf10, the main ligands for FgfR2-IIIb, are expressed in the mesenchyme surrounding the thymic epithelial primordium, and Fgf10-deficient mice also exhibit impaired thymic growth. Hence, Fgf signaling is essential for thymic epithelial proliferation. In addition to the proliferative block, most thymic epithelial cells fail to progress from an immature cytokeratin 5-positive to a cytokeratin 5-negative phenotype. Nevertheless, sufficient epithelial cell differentiation occurs in the severely hypoplastic thymus to allow the development of CD4/CD8-double-positive thymocytes and a very small number of single-positive thymocytes expressing TCRs.

There is considerable scope for the improvement of prescribing practices in the elderly, and particularly those with dementia. Importantly, level 1 anticholinergics have been identified as major contributors to the anticholinergic load in people with dementia. Longitudinal studies are required to determine the effects of increased and decreased anticholinergic load on cognitive function and other clinical outcomes for people with dementia.

ERBB2 is a receptor tyrosine kinase present on the basolateral membrane of polarized epithelia and has important functions in organ development and tumorigenesis. Using mutagenic analyses and Madin-Darby canine kidney (MDCK) cells, we have investigated the signals that regulate basolateral targeting of ERBB2. We show that basolateral delivery of ERBB2 is dependent on a novel bipartite juxtamembrane sorting signal residing between Gln-692 and Thr-701. The signal shows only limited sequence homology to known basolateral targeting signals and is both necessary and sufficient for correct sorting of ERBB2. In addition we demonstrate that this motif can function as a dominant basolateral targeting signal by its ability to redirect the apically localized P75 neurotrophin receptor to the basolateral membrane domain of polarized epithelial cells. Interestingly, LLC-PK1 cells, which are deficient for the 1B subunit of the AP1B adaptor complex, missort a large proportion of ERBB2 to the apical membrane domain. This missorting can be partially corrected by the introduction of 1B, suggesting a possible role for AP1B in ERBB2 endosomal trafficking. Furthermore, we find that the C-terminal ERBIN binding domain of ERBB2 is not necessary for its basolateral targeting in MDCK cells.

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Vagal nerve stimulation of the isolated guinea-pig oesophagus resulted in a triphasic contractile response which was abolished by tetrodotoxin. The mechanisms for each of the three responses were investigated. The first response was abolished by the neuromuscular blocking drug, tubocurarine, and was unaffected by atropine. The second response to vagal nerve stimulation was abolished by the ganglion blocking drug, hexamethonium, and by tubocurarine at a higher concentration than that required to block the first response. The second response was also abolished by atropine and was enhanced by physostigmine. It was concluded that this response was due to preganglionic stimulation of smooth muscle. omega-Conotoxin GVIA selectively inhibited the third response. This response was resistant to the neuromuscular and ganglion blocking drugs yet was abolished by atropine and was enhanced by physostigmine. This implicates the involvement of cholinergic neurones activated independently of nicotinic ganglionic receptors. The third response was also selectively abolished by capsaicin and enhanced by thiorphan. Contractile responses resulting from exogenous substance P were abolished by atropine and tetrodotoxin and enhanced by physostigmine. These findings suggest that the third response may be mediated by the action of a substance P-like neuropeptide released from sensory nerve endings which subsequently activate cholinergic neurones.

Background Individualizing goals for people with type 2 diabetes may result in deintensification of medication, but a comprehensive picture of deprescribing practices is lacking. Aims To conduct a scoping review in order to assess the rates, determinants and success of implementing deprescribing of glucose‐, blood pressure‐ or lipid‐lowering medications in people with diabetes. Methods A systematic search on MEDLINE and Embase between January 2007 and January 2019 was carried out for deprescribing studies among people with diabetes. Outcomes were rates of deprescribing related to participant characteristics, the determinants and success of deprescribing, and its implementation. Critical appraisal was conducted using predefined tools. Results Fourteen studies were included; eight reported on rates, nine on determinants and six on success and implementation. Bias was high for studies on success of deprescribing. Deprescribing rates ranged from 14% to 27% in older people with low HbA1c levels, and from 16% to 19% in older people with low systolic blood pressure. Rates were not much affected by age, gender, frailty or life expectancy. Rates were higher when a reminder system was used to identify people with hypoglycaemia, which led to less overtreatment and fewer hypoglycaemic events. Most healthcare professionals accepted the concept of deprescribing but differed on when to conduct it. Deprescribing glucose‐lowering medications could be successfully conducted in 62% to 75% of participants with small rises in HbA1c. Conclusions Deprescribing of glucose‐lowering medications seems feasible and acceptable, but was not widely implemented in the covered period. Support systems may enhance deprescribing. More studies on deprescribing blood pressure‐ and lipid‐lowering medications in people with diabetes are needed.

Background/AimsThe pacemaker mechanisms activating phasic contractions of vaginal and cervical smooth muscle remain poorly understood. Here, we investigate properties of pacemaking in vaginal and cervical tissues by determining whether: 1) functional pacemaking is dependent on the phase of the estrus cycle or pregnancy; 2) pacemaking involves Ca2+ release from sarcoplasmic/endoplasmic reticulum Ca2+-ATPase (SERCA) -dependent intracellular Ca2+ stores; and 3) c-Kit and/or vimentin immunoreactive ICs have a role in pacemaking.Methodology/Principal FindingsVaginal and cervical contractions were measured in vitro, as was the distribution of c-Kit and vimentin positive interstitial cells (ICs). Cervical smooth muscle was spontaneously active in estrus and metestrus but quiescent during proestrus and diestrus. Vaginal smooth muscle was normally quiescent but exhibited phasic contractions in the presence of oxytocin or the K+ channel blocker tetraethylammonium (TEA) chloride. Spontaneous contractions in the cervix and TEA-induced phasic contractions in the vagina persisted in the presence of cyclopiazonic acid (CPA), a blocker of the SERCA that refills intracellular SR Ca2+ stores, but were inhibited in low Ca2+ solution or in the presence of nifedipine, an inhibitor of L-type Ca2+channels. ICs were found in small numbers in the mouse cervix but not in the vagina.Conclusions/SignificanceCervical smooth muscle strips taken from mice in estrus, metestrus or late pregnancy were generally spontaneously active. Vaginal smooth muscle strips were normally quiescent but could be induced to exhibit phasic contractions independent on phase of the estrus cycle or late pregnancy. Spontaneous cervical or TEA-induced vaginal phasic contractions were not mediated by ICs or intracellular Ca2+ stores. Given that vaginal smooth muscle is normally quiescent then it is likely that increases in hormones such as oxytocin, as might occur through sexual stimulation, enhance the effectiveness of such pacemaking until phasic contractile activity emerges.