that ER-ȋ does not compensate for incompetent ER-Ȋ in this response. However, a proliferation response to strain was conferred on ERȊǁ/ǁ cells by transfecting them with a functional human wild-type ER-Ȋ expression vector (pRST7-ER;ref.8) (Fig. 1d).These results obtained in vivo and in vitro indicate that strain-related responses by differentiated cells of the osteoblast lineage require ER-Ȋ activity. This might explain why postmenopausal women no longer maintain adequate bone mass -their bone cells are less responsive to mechanical stimulation owing to decreased ER-Ȋ activity.The oestrogen receptor is the ancestral steroid receptor 9 , with one of its possible early reproductive functions being to induce brief communications

Osteoblast-like cells in primary cultures derived from ER␣؊/؊ mice do not proliferate in response to mechanical strain, unlike those from their ER␣ ؉/؉ littermates. ER␣ ؊/؊ cells also lack strainrelated NO production and responsiveness to IGFs. Proliferative responsiveness to strain is rescued by transfection with functional ER␣. ER␣ number or function in bone cells may limit bones' adaptability to mechanical loading.Introduction: In vivo, bones' osteogenic response to mechanical loading involves proliferation of surface osteoblasts. This response is replicated in vitro and involves ERK-mediated activation of the estrogen receptor (ER) ␣ and upregulation of estrogen response element activity. This proliferative response can be blocked by selective estrogen receptor modulators and increased by transfection of additional ER␣. Materials and Methods:We have now investigated the mechanisms of ER involvement in osteoblast-like cells' early responses to strain by comparing the responses of primary cultures of these cells derived from homozygous ER␣ knockout (ERKO) mice (ER␣

Objectives The aim of this study was to compare indications, complications and mortality rates for perineal urethrostomy (PU), transpelvic urethrostomy (TPU) and prepubic urethrostomy (PPU). Methods A retrospective review of, and follow-up owner questionnaire for, cats undergoing urethrostomy between 2008 and 2018, at a single referral hospital, were performed. Results Fifty-six cats underwent urethrostomy (PU, n = 37; TPU, n = 8; PPU, n = 11). The presenting problem was significantly associated with urethrostomy technique ( P <0.001). For PU cats, feline idiopathic cystitis (FIC; n = 21 [56.7%]) was the most common problem, whereas for PPU cats, trauma (n = 9 [81.8%]) was most common ( P <0.001). Urethrostomy technique was associated with imaging diagnosis ( P <0.001) of the urethral lesion. Most PU cats had no diagnostic imaging lesion (n = 15 [40.5%]) or obstructive calculi or clots (n = 10 [27.0%]), and all PPU cats had urethral rupture. Ten (90.9%) PPU cats had a pelvic lesion, while 21 (56.7%) PU cats had a penile lesion. TPU cats had a range of presenting problems and imaging diagnoses. Short- and long-term complications were reported in 33/55 (60.0%) and 11/30 (36.7%) cats, respectively. The number of cats with long-term complications was greater among PPU cats ( P = 0.02). Short-term dermatitis ( P = 0.019) and long-term incontinence ( P = 0.01) were associated with PPU. Short-term mortality was 5.6% and long-term mortality was 13.3%; both were independent of urethrostomy technique. Quality of life post-urethrostomy, across all techniques, was graded as good by 93% of owners. Conclusions and relevance In this study, PU was the most common feline urethrostomy technique indicated for FIC. Short-term urethrostomy complications are common, irrespective of urethrostomy technique. Long-term complications are less frequent but more common with PPU.

Dorsal plating of feline iliac fractures may reduce complications associated with pelvic canal narrowing such as constipation and megacolon.