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ABSTRACT Stopping treatment for osteoporosis with denosumab (Dmab) leads to a major and rapid loss in bone mineral density (BMD) and a risk of vertebral fracture. Subsequent treatment with bisphosphonate (Bp) does not completely prevent this bone loss. We carried out a prospective pilot study to find out whether the gradual dose reduction with denosumab could prevent this bone loss. We proposed a therapeutic protocol consisting in reducing the doses of Dmab to women treated with Dmab for postmenopausal osteoporosis. Six months after the last dose of Dmab 60 mg, the subsequent injection was performed with a reduced dose of 30 mg, and the month‐12 injection was a 15‐mg injection. BMD and serum C‐terminal telopeptide of type I collagen (CTX) were measured at the start of treatment with Dmab (T0), at the last dose with 60 mg (T1), and at 6 months (T2) and 12 months (T3) after the last 15 mg Dmab injection. We included 13 patients aged 68.7 ± 3 years, and treated with Dmab for 45.2 ± 5 months. At the lumbar spine, 39% of the initial gain in BMD was preserved 1 year after the last dose (15 mg). Conversely, at the hip, the bone loss at the end of the treatment reduction protocol was equivalent to the initial gain. The mean CTX level was 166 ± 152 pg/mL 6 months after the last dose (T2; 15 mg), and 549 ± 425 pg/mL 12 months after the last dose (T3; 15 mg). One patient presented two vertebral fractures, 8 months after the last dose of Dmab (15 mg). Gradual dose reduction of denosumab (30 mg then 15 mg) does not prevent bone loss in the hip and partially maintains the initial gain at the spine. © 2023 The Authors. JBMR Plus published by Wiley Periodicals LLC. on behalf of American Society for Bone and Mineral Research.

Abstract Background Pregnancy and breastfeeding are associated with bone density loss. Fracture occurrence during pregnancy and post-partum, and its determinants, remain poorly known in Osteogenesis Imperfecta (OI). The aim of this study was to characterize fractures that occurred during pregnancy and post-partum in OI patients. Results We conducted a retrospective multicentric study including a total of 50 previously pregnant OI women from 10 Bone Centers in France. Among these patients, 12 (24%) patients experienced fractures during pregnancy or in the 6 months following delivery, and 38 (76%) did not experience any fracture. The most frequent localizations were: proximal femur (25%), spine (25%), distal femur (12.5%), and pelvis (12.5%). Fractures during pregnancy occurred during the third trimester and post-partum fractures occurred with a mean delay of 2 months following delivery. No fractures occurred during childbirth. We next compared the 12 patients with pregnancy or post-partum fractures with the 38 patients without fractures. Mean age at pregnancy was 32.7 ± 3.1 years-old in the fractured group, vs 29.3 ± 5.0 years-old in the non-fractured group (p = 0.002). Breastfeeding was reported in 85.7% of patients in the fractured group, vs 47.1% in the non-fractured group (p = 0.03). All patients with post-partum fractures were breastfeeding. Bone mineral density was significantly lower in patients with pregnancy-related fractures compared with other patients: spine Z-score − 2.9 ± 1.6DS vs − 1.5 ± 1.7DS (p = 0.03), and total hip Z-score − 2.0 ± 0.7DS vs − 0.5 ± 1.4DS (p = 0.04). At least one osteoporosis-inducing risk factor or disease other than OI was identified in 81.8% vs 58.6% of fractured vs non-fractured patients (not significant). Fracture during pregnancy or post-partum was not associated with the severity of OI. Bisphosphonates before pregnancy were reported in 16.7% and 21.1% of patients with pregnancy-related fractures and non-fractured patients, respectively (not significant). Conclusions OI management during pregnancy and post-partum should aim for optimal control of modifiable osteoporosis risk factors, particularly in patients with low BMD. Breastfeeding should be avoided.

Aim: To describe the presenting features, bone characteristics and molecular genetics in a large monocentric cohort of children and young adults with idiopathic primary osteoporosis. Methods: Sixty-six patients (19 children, 47 adults; 28 males, 38 females; age at referral: 3.8 to 65 years) diagnosed with primary osteoporosis were included in this study; patients with features of osteogenesis imperfecta or other known syndromes associated with osteoporosis were excluded. For each patient, the following data were collected by retrospective chart review: family and personal history of fracture and osteoporosis, mineral homeostasis parameters and markers of bone formation and resorption, bone mineral density (BMD) of the lumbar spine (LS-BMD), the total body less head (TB-BMD), and total hip levels (TH-BMD) measured by DXA. As part of the initial assessment process, a bone fragility gene panel sequencing was performed in all of these patients. Results: There was a higher predominance of males in the children (63%) and of females in the adults (66%) (p = 0.030). Compared to the adults, the children had a significantly lower frequency of vertebral fractures (26 vs 57%, p = 0.022) and a higher frequency of peripheral fractures (84 vs 53%; p = 0.019). Bone fragility gene panel sequencing allowed the identification of the heterozygous pathogenic variant in 27% of patients (most frequently in LRP5, WNT1 and COL1A1 or 2 genes) and the heterozygous p.(Val667Met) LRP5 variant in 11% of them. The frequency of pathogenic variants tended to be higher in the children compared to the adults without reaching statistical significance (42 vs 19%; p = 0.053). The frequency of the p.(Val667Met) LRP5 variant was similar in children and adults. No significant differences were found regarding the various clinical, biological and radiological characteristics of the patients according to genotype. Conclusion: In this study, we reported the presenting features and bone characteristics in a large cohort of children and young adults with idiopathic primary osteoporosis. Bone fragility gene panel sequencing allowed the identification of genetic variants in a significant proportion of these patients. Molecular diagnosis in these patients is important in order to be able to offer genetic counselling and organise patient management.

ABSTRACT Treatment with asfotase alfa has transformed the prognosis of hypophosphatasia in children and improves the bone and muscle signs in adults. The doses used in adults are the same as in children, whereas bone remodeling is different between them. We report on the cases of two patients treated with 1 mg/kg/day of asfotase alfa who developed spinal cord compression from spinal ossifications during treatment. The first patient, 50 years old, presented after 2 years of treatment with quadraparesis secondary to an increase in ossifications of the cervical vertebral ligaments. The neurological damage was resolved after laminectomy, and the patient was then treated for 18 months with doses of 80 mg per week, without recurrence of the bone and muscle signs. The second patient, 26 years old, 78 kg, developed pain and cervical stiffness with pyramidal tract irritation secondary to ossifications of the vertebral ligaments. This improved with a reduction of doses to 80 mg/week, which then, after 6 months of follow‐up, enabled maintained improvement of the bone and muscle pain that was initially obtained. To our knowledge, these are the first reported cases of increased spinal ligamentous ossifications with neurological complications. Biological monitoring in adults does not seem to enable asfotase alfa doses to be adjusted. The levels of serum alkaline phosphatase (ALP) while on the recommended treatment of 1 mg/kg/day are significantly supraphysiological (5000 to 20,000 IU) and the assays of pyrophosphate and pyridoxal phosphate are not correlated with clinical efficacy. In both of our patients, the treatment with 80 mg of asfotase alfa per week, which was proposed after the occurrence of spinal complications, seemed as effective, after a follow‐up of 18 months and 6 months, as the initial treatment for improving the bone and muscle signs, and could be provided as “attack” doses after healing of the pseudoarthroses. © 2021 American Society for Bone and Mineral Research © 2020 The Authors. JBMR Plus published by Wiley Periodicals LLC. on behalf of American Society for Bone and Mineral Research.

Purpose: The occurrence of multiple vertebral fractures was reported after denosumab discontinuation. The use of bisphosphonates following denosumab has been suggested to prevent this bone loss. The aim of our observational trial was to evaluate the ability of risedronate to prevent the bone loss related to denosumab discontinuation in post-menopausal osteoporosis. Methods: Eighteen female patients, aged 69.8 years (56–79), were followed. All patients were prescribed 35 mg of risedronate per week for 3 months, starting when the next denosumab injection would have been administered. We measured BMD at denosumab initiation (T0), denosumab withdrawal (T1), and nine months after the discontinuation of risedronate (1 year post-denosumab: T2). Results: 1 year after denosumab discontinuation, the mean bone loss at the spine was – 4.6 ± 5.2% for the total population, −0.3 ± 2.3% in patients with prior exposure to bisphosphonates, −6.3 ± 5.7% in patients with prior exposure to teriparatide, and − 7.6 ± 3.5% in naïve patients. Spine BMD loss after the risedronate bridging therapy (T2 vs. T1) was significantly lower in patients who experienced prior exposure to bisphosphonates, when compared to naïve patients (p = .0190) and to patients with prior teriparatide exposure (p = .0176). 1 year after denosumab discontinuation, the mean densitometric loss at the hip was −1.8 ± 3.4% in the total cohort, −0.6 ± 1.8% in the patients previously treated with bisphosphonates, −1.5 ± 4.7% in the patients previously treated with teriparatide, and − 4.2 ± 0.6 in naïve patients. The mean densitometric loss during the off-denosumab period was lower in patients with previous bisphosphonate exposure than in naïve patients (p = .043) and in patients with previous exposure to teriparatide (p = .05). Conclusions: Three months of risedronate treatment does not prevent bone loss in patients who have not been treated with bisphosphonates before denosumab.

During the Mars 160 Mission in 2016 and 2017, crews at the Mars Desert Research Station (MDRS) in Utah, USA and the Flashline Mars Arctic Research Station (FMARS) on Tallurutit (Devon Island), Nunavut, Canada, conducted a collections‑based survey of lichen biodiversity at each of these Martian planetary analogs. Here we present the results of these studies as two annotated checklists, including 35 lichen spe‑ cies from MDRS and 13 species from FMARS, alongside details on the distribution of these species, relevant taxonomic notes, and photos of each species as an identification aid. This work adds to our knowledge of the biodiversity of these unique sites and provides an important baseline for future analog research at these stations.

Cells of four reference strains (Scott A, LO 28, CNL 895807 and ATCC 19115) and of five recent food isolates (A00M011, A00M018, A00M087, A00M092 and A00M123) of Listeria monocytogenes were grown until late exponential phase in Brain Heart Broth at two different temperatures (37 °C and 4 °C). Our results show that significant differences exist between the cellular lipid fatty acid profile of reference and recent food isolates. Like the reference strains, and in keeping with previous reports on the cellular lipid fatty acid profile of L. monocytogenes, the recent food isolates were characterised by the presence of ai15:0, i15:0 and ai17:0. In addition, the fatty acid ai13:0 was observed in all of the recent food isolates grown at 4 °C, whereas only two reference strains, Scott A and LO 28, showed ai13:0 in their cellular lipid fatty acid profile at 4 °C. When grown at 4 °C, the recent food isolates showed a mean aiC15/aiC17 ratio of 66, while reference strains were characterised by significantly lower ratios, ranging between 4.3 (ATCC 19115) and 28.9 (Scott A). These results showed that all of the recent food isolates, Scott A and LO28 strains use chain length and anteiso-branching (ai15:0) as their major response to cold temperature adaptation. However, the cold adaptation response of reference strains CNL 895807 and ATCC 19115 appears to be different. [ABSTRACT FROM AUTHOR]