Short-term dietary restriction in old mice rejuvenates the aging-induced structural imbalance of gut microbiota.

The world's aging population is growing rapidly. Incidences of multiple pathologies, such as abdominal obesity, cardiovascular and cerebrovascular diseases, type 2 diabetes, and malignant neoplasms, increase sharply with age. Aged individuals possess a significantly shifted composition of gut microbiota, which is suggested to play important roles in aging associated pathologies. Whether the existing shifted structural composition of microbiota in aged populations can be reverted non-pharmacologically has not been studied so far. Here, we show an intestinal flora imbalance in old C57BL/6J mice with a remarkable dominant proportion of microbes promoting lipid metabolism and inflammation. Intriguingly, short-term (2 months) dietary restriction was enough to significantly revert the imbalance of intestinal flora in aged mice toward a more balanced structural composition as shown in young mice. Our study provides the first evidence that short-term dietary restriction in old mice can restore the already dysfunctional aged gut microbiota. Our study provides the first evidence that short-term dietary restriction in old mice can restore the already dysfunctional aged gut microbiota, which may help ameliorate aging-related disorders plaguing the vast elderly population.

Representações sociais, zona muda e práticas sociais femininas sobre envelhecimento e rejuvenescimento / Social representations, mute zone and social practices female about aging and rejuvenation / Representaciones sociales, zona muda y prácticas sociales femeninas sobre envejecimiento y rejuvenecimiento

O presente estudo objetivou investigar as representações sociais, a zona muda e as práticas femininas sobre envelhecimento e rejuvenescimento. Participaram 40 mulheres com idade entre 30 e 60 anos. Metade utilizava procedimentos rejuvenescedores não invasivos e a outra metade fazia uso de procedimentos rejuvenescedores invasivos ou minimamente invasivos. Foram apresentadas às participantes histórias sobre práticas rejuvenescedoras utilizadas por duas mulheres, a Mulher 1 adota procedimentos rejuvenescedores não invasivos, e a Mulher 2 adota procedimentos invasivos. Os resultados mostraram que as participantes representaram a Mulher 1 como alguém que deve trabalhar muito, possivelmente como professora, enquanto a Mulher 2 teria boas condições financeiras trabalhando possivelmente no ramo da estética. A Mulher 1 é considerada, principalmente pelo grupo de mulheres que adotam práticas de rejuvenescimento não invasivas como feliz e altruísta, enquanto a Mulher 2 é apontada como infeliz e egoísta pelo mesmo grupo.

This study aimed to investigate the social representations, the mute zone and women's practices on aging and rejuvenation. Participants were 40 women aged between 30 and 60 years. Half of them used non-invasive rejuvenating procedures, and the other half use invasive or minimally invasive rejuvenating procedures. Were presented to the participants stories about rejuvenating practices used by two women, one Woman adopts non-invasive rejuvenating procedures, and the Woman adopts 2 invasive procedures. The results showed that the participants represented the Woman 1 as someone who must work very hard, possibly as a teacher, while Women 2 has good financial conditions possibly working in the cosmetic area. Woman 1 is considered, especially by the group of women who adopt non-invasive rejuvenation practices as a happy and selfless, while Woman 2 is seen as unfortunate and selfish by the same group.

El presente estudio tuvo como objetivo investigar las representaciones sociales de la zona muda y las prácticas femeninas sobre envejecimiento y rejuvenecimiento. Participaron 40 mujeres con edad entre 30 y 60 años. La mitad utilizaba procedimientos rejuvenecedores no invasivos, y la otra mitad hacía uso de procedimientos rejuvenecedores invasivos o mínimamente invasivos. Fueron presentadas a las participantes historias sobre prácticas rejuvenecedoras utilizadas por dos mujeres. La Mujer 1 adopta procedimientos rejuvenecedores no invasivos, y la Mujer 2 adopta procedimientos invasivos. Las participantes representaron a la Mujer 1 como alguien que debe trabajar mucho, como profesora, mientras que la Mujer 2 tendría buenas condiciones financieras trabajando en el ramo de la estética. La Mujer 1 es considerada, principalmente por el grupo de mujeres que adoptan prácticas de rejuvenecimiento no invasivas, como feliz y altruista, mientras que la Mujer 2 es señalada como infeliz y egoísta por el mismo grupo.

How to Approach a Recalled Dual Modular Hip Implant: An Update.

BACKGROUND: The aim of this study was to provide an update on the "Modular taper junction corrosion and failure: how to approach a recalled total hip arthroplasty implant" (Pivec et al JOA 2014) publication. METHODS: We performed a comprehensive review of the literature in English, with search terms referencing to the diagnosis, management, and outcomes of patients who underwent total hip arthroplasty with a recalled dual modular hip implant. RESULTS: Based on this review and the new guidelines by the American Academy of Orthopedic Surgeons and the Hip Society, we propose an updated algorithm for the diagnosis and management of patients with these recalled implants. CONCLUSION: When encountering patients with these prostheses, it is imperative to take a step-by-step approach to evaluate whether patients are having potential complications. We hope that this has further clarified the appropriate steps that need to be carried out when confronted with these recalled devices.

Short-Term Outcomes and Complications After Rejuvenate Modular Total Hip Arthroplasty Revision.

BACKGROUND: The early short-term outcomes and complications after revision of the recalled Rejuvenate modular neck hip arthroplasty have not been previously reported. This study's purpose is to describe the early outcomes and complications after revision of the Rejuvenate modular femoral neck. METHODS: A retrospective cohort included 92 patients with 92 Rejuvenate modular neck total hip arthroplasty (THA) who underwent revision surgery between July 2011 and April 2014. Preoperative, 1-year, and 2-year patient-reported outcome measures including Western Ontario and McMaster Universities Arthritis Index (WOMAC) and Short Form 12 (SF-12) were described in 92 patients. RESULTS: Complications arose in (12 of 92) 13% of patients including 8 greater trochanteric fractures, 1 intraoperative periprosthetic acetabular fracture, 2 dislocations, 1 early aseptic loosening, and 1 infection requiring a 2-stage revision. Overall, 66% of patients with a complication required reoperation. Significant changes were noted between preoperative and 1- and 2-year outcomes with respect to WOMAC pain score (P = .0031), WOMAC total score (P = .021), SF-12 mental component score (P < .0001), and physical component score (P < .0001). CONCLUSIONS: Patients can expect an improvement in pain (WOMAC pain) and function (total WOMAC, SF-12 Physical Health Composite Scale), but overall worsening in the SF-12 mental component scores. Patients' physical function improvements are offset by worsened mental function scores. Patients undergoing revision of Rejuvenate modular neck THA implants should be counseled on modest functional improvements and relative frequency of complications.

Quantification of material loss from the neck piece taper junctions of a bimodular primary hip prosthesis. A retrieval study from 27 failed Rejuvenate bimodular hip arthroplasties.

The early failure and revision of bimodular primary total hip arthroplasty prostheses requires the identification of the risk factors for material loss and wear at the taper junctions through taper wear analysis. Deviations in taper geometries between revised and pristine modular neck tapers were determined using high resolution tactile measurements. A new algorithm was developed and validated to allow the quantitative analysis of material loss, complementing the standard visual inspection currently used. The algorithm was applied to a sample of 27 retrievals (in situ from 2.9 to 38.1 months) of the withdrawn Rejuvenate modular prosthesis. The mean wear volumes on the flat distal neck piece taper was 3.35 mm(3) (0.55 to 7.57), mainly occurring in a characteristic pattern in areas with high mechanical loading. Wear volume tended to increase with time to revision (r² = 0.423, p = 0.001). Implant and patient specific data (offset, stem size, patient's mass, age and body mass index) did not correlate with the amount of material loss observed (p > 0.078). Bilaterally revised implants showed higher amounts of combined total material loss and similar wear patterns on both sides. The consistent wear pattern found in this study has not been reported previously, suggesting that the device design and materials are associated with the failure of this prosthesis.

Corrosion and Adverse Local Tissue Reaction in One Type of Modular Neck Stem.

Modular neck stems allow for optimization of joint biomechanics by restoring anteversion, offset, and limb length. A potential disadvantage is the generation of metal ions from fretting and crevice corrosion. We identified 118 total hip arthroplasty implanted with one type of dual-modular femoral component. Thirty-six required revision due to adverse local tissue reaction. Multivariate analysis isolated females and low offset necks as risk factors for failure. Kaplan-Meir analysis revealed small stem sizes failed at a higher rate during early follow-up period. Although the cobalt/chrome levels were higher in the failed group, these tests had low diagnostic accuracy for ALTR, while MRI scan was more sensitive. We conclude that the complications related to the use of dual modular stems of this design outweigh the potential benefits.

Short-Term Metal Ion Trends Following Removal of Recalled Modular Neck Femoral Stems.

Elevated serum metal ions have been well documented with the Rejuvenate modular neck femoral stem (Stryker, Mahwah, NJ); however, the rate at which ion levels decline following revision is less clear. This study included fifty-nine consecutive revisions of Rejuvenate stems for symptomatic ALTR. Blood tests prior to revision and postoperatively at 6weeks, 3months, 6months, and 1year measured serum cobalt and chromium concentrations, ESR, and CRP. At six weeks following revision of a unilateral Rejuvenate, cobalt and chromium levels dropped from preoperative levels by 67% and 42%, respectively. At three months, cobalt levels declined to 19% of preoperative values, but chromium levels remained stable. With this information, surgeons can set realistic expectations for serum metal ion levels following Rejuvenate stem revision.

Revision of Recalled Modular Neck Rejuvenate and ABG Femoral Implants.

Modular neck femoral stems have been associated with adverse local tissue reactions (ALTR), leading to a voluntary recall, but these effects have not been well-characterized. A retrospective review of intraoperative findings and cobalt/chromium levels was performed in 103 hips undergoing revision for ALTR. The average preoperative serum cobalt level was 7.6 µg/L (range 1.1-23 µg/L) and chromium level was 1.8 µg/L (range 0.1-6.8 µg/L). Metallic sludge was noted in 100%, synovitis in 98%, pericapsular rind in 82%, and calcar erosion in 85%. An osteotomy was required for removal in 44%. We concluded that revision of modular neck femoral stems is associated with increased preoperative metal ion levels and stem-neck corrosion. Despite advanced stem explantation techniques, osteotomy was frequently required, leading to increased morbidity.