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81.
Modifications to the constituents of the gut microbiome influence bone density and tissue-level strength, but the specific microbial components that influence tissue-level strength in bone are not known. Here, we selectively modify constituents of the gut microbiota using narrow-spectrum antibiotics to identify components of the microbiome associated with changes in bone mechanical and material properties. Male C57BL/6J mice (4 weeks) were divided into seven groups (n = 7–10/group) and had taxa within the gut microbiome removed through dosing with: (i) ampicillin; (ii) neomycin; (iii) vancomycin; (iv) metronidazole; (v) a cocktail of all four antibiotics together (with zero-calorie sweetener to ensure intake); (vi) zero-calorie sweetener only; or (vii) no additive (untreated) for 12 weeks. Individual antibiotics remove only some taxa from the gut, while the cocktail of all four removes almost all microbes. After accounting for differences in geometry, whole bone strength was reduced in animals with gut microbiome modified by neomycin (−28%, p = 0.002) and was increased in the group in which the gut microbiome was altered by sweetener alone (+39%, p < 0.001). Analysis of the fecal microbiota detected seven lower-ranked taxa differentially abundant in animals with impaired tissue-level strength and 14 differentially abundant taxa associated with increased tissue-level strength. Histological and serum markers of bone turnover and trabecular bone volume per tissue volume (BV/TV) did not differ among groups. These findings demonstrate that modifications to the taxonomic components of the gut microbiome have the potential to decrease or increase tissue-level strength of bone independent of bone quantity and without noticeable changes in bone turnover. © 2021 American Society for Bone and Mineral Research (ASBMR).  相似文献   
82.
The current standard for composite tissue preservation is static cold storage (SCS) and is limited to 6 h until irreversible muscle damage occurs. Extracorporeal perfusion (ECP) is a promising technique for prolonged preservation, however, functional results have been scarcely researched. This article assessed neuromuscular function and compared results to histological alterations to predict muscle damage after ECP. Forelimbs of twelve Dutch landrace pigs were amputated and preserved by 4 h SCS at 4–6 °C (n = 6) or 18 h mid-thermic ECP with University of Wisconsin solution (n = 6). Limbs were replanted and observed for 12 h. Sham surgery was performed on contralateral forelimbs (n = 12). Histology analysis scored four subgroups representing different alterations (higher score equals more damage). Muscle contraction after median nerve stimulation was comparable between ECP, SCS, and sham limbs (P = 0.193). Histology scores were higher in ECP limbs compared to SCS limbs (4.8 vs. 1.5, P = 0.013). This was mainly based on more oedema in these limbs. In-vivo muscle contraction was well preserved after 18 h ECP compared to short SCS, although histology seemed inferior in this group. Histology, therefore, did not correlate to muscle function at 12 h after replantation. This leads to the question whether histology or neuromuscular function is the best predictor for transplant success.  相似文献   
83.
Skeletal homeostasis critically depends on the proper anabolic functioning of osteolineage cells. Proliferation and matrix synthesis are highly demanding in terms of biosynthesis and bioenergetics, but the nutritional requirements that support these processes in bone-forming cells are not fully understood. Here, we show that glutamine metabolism is a major determinant of osteoprogenitor function during bone mass accrual. Genetic inactivation of the rate-limiting enzyme glutaminase 1 (GLS1) results in decreased postnatal bone mass, caused by impaired biosynthesis and cell survival. Mechanistically, we uncovered that GLS1-mediated glutamine catabolism supports nucleotide and amino acid synthesis, required for proliferation and matrix production. In addition, glutamine-derived glutathione prevents accumulation of reactive oxygen species and thereby safeguards cell viability. The pro-anabolic role of glutamine metabolism was further underscored in a model of parathyroid hormone (PTH)-induced bone formation. PTH administration increases glutamine uptake and catabolism, and GLS1 deletion fully blunts the PTH-induced osteoanabolic response. Taken together, our findings indicate that glutamine metabolism in osteoprogenitors is indispensable for bone formation. © 2020 American Society for Bone and Mineral Research (ASBMR).  相似文献   
84.
Regional anaesthetic techniques are fundamental in the anaesthetic care of orthopaedic patients. They may be used as the primary anaesthetic technique or to provide postoperative pain relief. Compared to general anaesthesia alone, regional techniques can provide superior perioperative analgesia, fewer systemic drug adverse effects such as nausea, vomiting and confusion, and earlier mobilization which can reduce nosocomial complications and facilitate expedited hospital discharge. Disadvantages include block failure, nerve injury, unrecognised injury to the anaesthetised limb, prolonged motor blockade and local anaesthetic toxicity. Preoperative assessment should identify contraindications, document pre-existing neurological deficits, and clarify surgical and perioperative aims. Informed consent should be obtained after a clear explanation of the procedure, its risks, and potential complications. Serious and long-term neurological complications are rare and may be reduced by an awake regional technique, sonographic guidance, regular aspiration and by ensuring low pressure injections. Postoperative follow-up is essential and suspicious neurological findings should be detected, investigated, and managed in an early and timely manner.  相似文献   
85.
Background: Telemedicine is an evolving tool to increase patients’ access to subspecialty care. Since 2014, Arkansas has been utilizing telemedicine in the evaluation of patients with hand injuries. The purpose of this study is to assess the effect of this novel telemedicine system for the management of hand trauma on patient transfer. Methods: We reviewed data from the first year of the telemedicine program (2014) and compared it to data from the year prior (2013). Data collection from both years included number of hand consults and need for transfer. From the 2014 data, we also recorded the use of telemedicine, type of transfer, distance of transfer, and time to disposition. Results: During 2013 (pre-telemedicine), there were 263 hand traumas identified. In all, 191 (73%) injuries required transfer to a higher level of care, while 72 (23%) were managed locally. In the first year of the telemedicine program (2014), a total of 331 hand injuries were identified. A total of 298 (90%) resulted in telemedicine consultation with 65% (195) utilizing video encounters. After telemedicine consultation, local management was recommended for 164 injuries (55%) while transfer was recommended for 134 (45%). Using telemedicine, there was a significant decrease in the percentage of transfer for hand injuries (P < .001). Conclusions: The telemedicine program was well utilized and provided patients throughout the state with continuous access to fellowship trained hand surgeons including regions where hand subspecialty care is not available. The program resulted in a significant decrease in the number of hospital transfers for the management of acute hand trauma.  相似文献   
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Recent studies showed that the COVID‐19 pandemic caused collateral damage in health care in terms of reduced hospital submissions or postponed treatment of other acute or chronic ill patients. An anonymous survey was sent out by mail to patients with chronic wounds in order to evaluate the impact of the pandemic on wound care. Sixty‐three patients returned the survey. In 14%, diagnostic workup or hospitalisation was cancelled or postponed. Thirty‐six percent could not seek consultation by their primary care physician as usual. The use of public transport or long travel time was not related to limited access to medical service (P = .583). In ambulatory care, there was neither a significant difference in the frequency of changing wound dressings (P = .67), nor in the person, who performed wound care (P = .39). There were no significant changes in wound‐specific quality of life (P = .505). No patient used telemedicine in order to avoid face‐to‐face contact or anticipate to pandemic‐related restrictions. The COVID‐19 pandemic impaired access to clinical management of chronic wounds in Germany. It had no significant impact on ambulatory care or wound‐related quality of life. Telemedicine still plays a negligible role in wound care.  相似文献   
90.

Emotion dysregulation and intimacy problems are theoretically underpinned correlates of hypersexuality (i.e., uncontrollable sexual urges, fantasies, and behaviors resulting in distress and impairment in different areas of functioning), but the directionality of these associations has not been established, as work in this area has relied on cross-sectional designs. Moreover, although hypersexuality may have significant adverse effects on romantic relationships and approximately half of treatment-seeking individuals are in a relationship, prior studies almost exclusively involved samples of men, regardless of their relationship status. The aim of the present study was to examine the directionality of associations between both partners’ emotion dysregulation, physical (i.e., partnered sexual frequency) and relationship intimacy, and hypersexuality using a longitudinal, dyadic framework. Self-reported data of 267 mixed-sex couples (Mage_men?=?29.9 years, SD?=?8.2; Mage_women?=?27.7 years, SD?=?6.7) at baseline (T1) and six-month follow-up (T2) were analyzed using a crossed-lagged model within an actor–partner interdependence framework. Prior greater emotion dysregulation (T1) in both men and women was associated with their own later greater hypersexuality (T2). Women’s prior greater hypersexuality (T1) was associated with their later lower relationship intimacy (T2). Lower levels of intimacy were not significantly associated with later hypersexuality. No partner effects were found in relation to hypersexuality. Findings suggest that men and women may use sexual behaviors to cope with negative emotions, which could, in turn, lead to hypersexuality. Intimacy problems did not precede hypersexuality, although women’s hypersexuality may reduce their own relationship intimacy over time.

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