8 research outputs found
Association of physical exercise and calcium intake with bone mass measured by quantitative ultrasound
<p>Abstract</p> <p>Background</p> <p>Interventions other than medications in the management of osteoporosis are often overlooked. The purpose of this study was to investigate the association of physical activity and calcium intake with bone parameters.</p> <p>Methods</p> <p>We measured the heel T-score and stiffness index (SI) in 1890 pre- and postmenopausal women by quantitative ultrasound (QUS) and assessed physical activity and dietary calcium intake by questionnaire. Participants were divided according to their weekly physical activity (sedentary, moderately active, systematically active) and daily calcium consumption (greater than or less than 800 mg/day).</p> <p>Results</p> <p>SI values were significantly different among premenopausal groups (p = 0.016) and between sedentary and systematically active postmenopausal women (p = 0.039). QUS T-scores in systematically active premenopausal women with daily calcium intake > 800 mg/day were significantly higher than those in all other activity groups (p < 0.05) independent of calcium consumption.</p> <p>Conclusions</p> <p>Systematic physical activity and adequate dietary calcium intake are indicated for women as a means to maximize bone status benefits.</p
Platelet-rich Plasma and Mesenchymal Stem Cells Local Infiltration Promote Functional Recovery and Histological Repair of Experimentally Transected Sciatic Nerves in Rats
Introduction
Platelet-rich plasma (PRP) products and mesenchymal stem cells (MSCs)
seem to have a significant potential as neurogenic therapeutic modulator
systems. This study aimed to investigate such biological blood
derivatives that could enhance nerve regeneration when applied locally
in the primary repair of peripheral nerve transection of an experimental
rat model.
Methods
A total of 42 two-month-old male Wistar rats were divided into three
“treatment” groups (control, PRP, and MSCs). All the subjects were
operated under anesthesia, and the surgical site was infiltrated with
either normal saline, PRP derived from the animal’s peripheral blood, or
MSCs derived from the animal’s femoral bone marrow. All three groups
were also sub-divided into two sub-groups based on the post-operative
administration of Non-steroidal anti-inflammatory drugs (NSAIDs) or not
in order to evaluate the effect of NSAIDs on the final outcome. Three
months post-surgery, electromyography evaluation of both hind limbs
(right operated and left non-operated) was performed. The animals were
euthanized, and nerve repair specimens were prepared for histology.
Results
PRP group had a significant effect (p<0.05) on the sciatic nerve repair
when compared with the control group, whereas the MSC group had a
positive effect but was not statistically significant (p=0.2). The
number of counted neural axons at the area distal to the nerve repair
site were significantly repetitive (p<0.05) in both the PRP and MSC
groups when compared with the control group.
Conclusions
Both PRP and MSCs appear to play an essential role in the enhancement of
nerve repair in terms of functionality and histology. MSCs group
demonstrated a positive effect, whereas the PRP group showed
statistically significant better results
Evaluation of Femoral Bone Fracture Healing in Rats by the Modal Damping Factor and Its Correlation With Peripheral Quantitative Computed Tomography
Introduction
Monitoring the progress of fracture healing is essential in order to
establish the appropriate timing that ensures adequate bone strength for
weight-bearing. In the present experimental study on a rat model of
femoral fracture healing, the measurement of bone density and strength
by peripheral quantitative computerized tomography (pQCT) was correlated
with the modal damping factor (MDF) method.
Methods
Four groups of 12 male six-month-old Wistar rats each were anesthetized
and submitted to baseline femoral pQCT and MDF scanning, followed by
aseptic midshaft osteotomy of the right femur which was fixed by a
locking intramedullary nail technique. The animals were left to recover
and re-scanned following euthanasia of each group after six, eight, 10,
and 12 weeks, respectively. The parameters measured by the pQCT method
were total bone mineral density (BMD) and polar strength strain index
(SSIp).
Results
Fracture healing progressed over time and at 12 weeks post-osteotomy
there was no statistically significant difference between the
osteotomized right and the control left femurs regarding MDF, BMD, and
SSIp measurements. The highest correlations for the osteotomized femurs
were observed between MDF and BMD (r = -0.647, P = 0.043), and between
MDF and SSIp (r = -0.350, P = 0.321), at 10 weeks postoperatively. The
high to moderate correlations between MDF and BMD, and between MDF and
SSIp respectively, support the validity of MDF in assessing fracture
healing.
Conclusions
Based on our findings in this fracture healing animal model, the results
from the MDF method are reliable and correlate highly with the total BMD
and moderately with the SSI polar values obtained by the pQCT method of
bone quality measurement. Further studies are needed which may
additionally support that the MDF method can be an attractive portable
alternative to monitor fracture healing in the community
The Effect of Strontium Ranelate on Fracture Healing: An Animal Study
Background. Strontium ranelate (StR) is an antiosteoporotic agent previously utilized for the enhancement of fracture union. We investigated the effects of StR on fracture healing using a rabbit model. Methods. Forty adult female rabbits were included in the study and were divided in 2 equal groups, according to StR treatment or untreated controls. All animals were subjected to osteotomy of the ulna, while the contralateral ulna remained intact and served as a control for the biomechanical assessment of fracture healing. Animals in the study group received 600 mg/kg/day of StR orally. All animals received ordinary food. At 2 and 4 weeks, all animals were euthanatized and the osteotomy sites were evaluated for healing through radiological, biomechanical, and histopathological studies. Results. The treatment group presented statistically significant higher callus diameter, total callus area, percentage of fibrous tissue (p<0.001), vessels/mm2, number of total vessels, and lower osteoclast number/mm2 (p<0.05) than the control group at 2 weeks. Additionally, the treatment group presented significantly higher percentages of new trabecular bone, vessels/mm2, osteoclast number/mm2, and lower values for callus diameter, as well as total callus area (p<0.05), than the control group at 4 weeks. At 4 weeks, in the treatment group, force applied (p=0.003), energy at failure (p=0.004), and load at failure (p=0.003) were all significantly higher in the forearm specimens with the osteotomized ulnae compared to those without. Radiological bone union was demonstrated for animals receiving StR at 4 weeks compared with controls (p=0.045). Conclusion. StR appears to enhance fracture healing but further studies are warranted in order to better elucidate the mechanisms and benefits of StR treatment
The Effect of Strontium Ranelate on Fracture Healing: An Animal Study
Background. Strontium ranelate (StR) is an antiosteoporotic agent
previously utilized for the enhancement of fracture union. We
investigated the effects of StR on fracture healing using a rabbit
model. Methods. Forty adult female rabbits were included in the study
and were divided in 2 equal groups, according to StR treatment or
untreated controls. All animals were subjected to osteotomy of the ulna,
while the contralateral ulna remained intact and served as a control for
the biomechanical assessment of fracture healing. Animals in the study
group received 600 mg/kg/day of StR orally. All animals received
ordinary food. At 2 and 4 weeks, all animals were euthanatized and the
osteotomy sites were evaluated for healing through radiological,
biomechanical, and histopathological studies. Results. The treatment
group presented statistically significant higher callus diameter, total
callus area, percentage of fibrous tissue (p<0.001), vessels/mm(2),
number of total vessels, and lower osteoclast number/mm(2) (p<0.05) than
the control group at 2 weeks. Additionally, the treatment group
presented significantly higher percentages of new trabecular bone,
vessels/mm(2), osteoclast number/mm(2), and lower values for callus
diameter, as well as total callus area (p<0.05), than the control group
at 4 weeks. At 4 weeks, in the treatment group, force applied (p=0.003),
energy at failure (p=0.004), and load at failure (p=0.003) were all
significantly higher in the forearm specimens with the osteotomized
ulnae compared to those without. Radiological bone union was
demonstrated for animals receiving StR at 4 weeks compared with controls
(p=0.045). Conclusion. StR appears to enhance fracture healing but
further studies are warranted in order to better elucidate the
mechanisms and benefits of StR treatment
Global variation in postoperative mortality and complications after cancer surgery: a multicentre, prospective cohort study in 82 countries
© 2021 The Author(s). Published by Elsevier Ltd. This is an Open Access article under the CC BY-NC-ND 4.0 licenseBackground: 80% of individuals with cancer will require a surgical procedure, yet little comparative data exist on early outcomes in low-income and middle-income countries (LMICs). We compared postoperative outcomes in breast, colorectal, and gastric cancer surgery in hospitals worldwide, focusing on the effect of disease stage and complications on postoperative mortality. Methods: This was a multicentre, international prospective cohort study of consecutive adult patients undergoing surgery for primary breast, colorectal, or gastric cancer requiring a skin incision done under general or neuraxial anaesthesia. The primary outcome was death or major complication within 30 days of surgery. Multilevel logistic regression determined relationships within three-level nested models of patients within hospitals and countries. Hospital-level infrastructure effects were explored with three-way mediation analyses. This study was registered with ClinicalTrials.gov, NCT03471494. Findings: Between April 1, 2018, and Jan 31, 2019, we enrolled 15 958 patients from 428 hospitals in 82 countries (high income 9106 patients, 31 countries; upper-middle income 2721 patients, 23 countries; or lower-middle income 4131 patients, 28 countries). Patients in LMICs presented with more advanced disease compared with patients in high-income countries. 30-day mortality was higher for gastric cancer in low-income or lower-middle-income countries (adjusted odds ratio 3·72, 95% CI 1·70–8·16) and for colorectal cancer in low-income or lower-middle-income countries (4·59, 2·39–8·80) and upper-middle-income countries (2·06, 1·11–3·83). No difference in 30-day mortality was seen in breast cancer. The proportion of patients who died after a major complication was greatest in low-income or lower-middle-income countries (6·15, 3·26–11·59) and upper-middle-income countries (3·89, 2·08–7·29). Postoperative death after complications was partly explained by patient factors (60%) and partly by hospital or country (40%). The absence of consistently available postoperative care facilities was associated with seven to 10 more deaths per 100 major complications in LMICs. Cancer stage alone explained little of the early variation in mortality or postoperative complications. Interpretation: Higher levels of mortality after cancer surgery in LMICs was not fully explained by later presentation of disease. The capacity to rescue patients from surgical complications is a tangible opportunity for meaningful intervention. Early death after cancer surgery might be reduced by policies focusing on strengthening perioperative care systems to detect and intervene in common complications. Funding: National Institute for Health Research Global Health Research Unit
Effects of hospital facilities on patient outcomes after cancer surgery: an international, prospective, observational study
© 2022 The Author(s). Published by Elsevier Ltd. This is an Open Access article under the CC BY 4.0 licenseBackground: Early death after cancer surgery is higher in low-income and middle-income countries (LMICs) compared with in high-income countries, yet the impact of facility characteristics on early postoperative outcomes is unknown. The aim of this study was to examine the association between hospital infrastructure, resource availability, and processes on early outcomes after cancer surgery worldwide. Methods: A multimethods analysis was performed as part of the GlobalSurg 3 study—a multicentre, international, prospective cohort study of patients who had surgery for breast, colorectal, or gastric cancer. The primary outcomes were 30-day mortality and 30-day major complication rates. Potentially beneficial hospital facilities were identified by variable selection to select those associated with 30-day mortality. Adjusted outcomes were determined using generalised estimating equations to account for patient characteristics and country-income group, with population stratification by hospital. Findings: Between April 1, 2018, and April 23, 2019, facility-level data were collected for 9685 patients across 238 hospitals in 66 countries (91 hospitals in 20 high-income countries; 57 hospitals in 19 upper-middle-income countries; and 90 hospitals in 27 low-income to lower-middle-income countries). The availability of five hospital facilities was inversely associated with mortality: ultrasound, CT scanner, critical care unit, opioid analgesia, and oncologist. After adjustment for case-mix and country income group, hospitals with three or fewer of these facilities (62 hospitals, 1294 patients) had higher mortality compared with those with four or five (adjusted odds ratio [OR] 3·85 [95% CI 2·58–5·75]; p<0·0001), with excess mortality predominantly explained by a limited capacity to rescue following the development of major complications (63·0% vs 82·7%; OR 0·35 [0·23–0·53]; p<0·0001). Across LMICs, improvements in hospital facilities would prevent one to three deaths for every 100 patients undergoing surgery for cancer. Interpretation: Hospitals with higher levels of infrastructure and resources have better outcomes after cancer surgery, independent of country income. Without urgent strengthening of hospital infrastructure and resources, the reductions in cancer-associated mortality associated with improved access will not be realised. Funding: National Institute for Health and Care Research