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1.
Nature ; 544(7649): 207-211, 2017 04 13.
Artigo em Inglês | MEDLINE | ID: mdl-28355177

RESUMO

Transient control over the atomic potential-energy landscapes of solids could lead to new states of matter and to quantum control of nuclear motion on the timescale of lattice vibrations. Recently developed ultrafast time-resolved diffraction techniques combine ultrafast temporal manipulation with atomic-scale spatial resolution and femtosecond temporal resolution. These advances have enabled investigations of photo-induced structural changes in bulk solids that often occur on timescales as short as a few hundred femtoseconds. In contrast, experiments at surfaces and on single atomic layers such as graphene report timescales of structural changes that are orders of magnitude longer. This raises the question of whether the structural response of low-dimensional materials to femtosecond laser excitation is, in general, limited. Here we show that a photo-induced transition from the low- to high-symmetry state of a charge density wave in atomic indium (In) wires supported by a silicon (Si) surface takes place within 350 femtoseconds. The optical excitation breaks and creates In-In bonds, leading to the non-thermal excitation of soft phonon modes, and drives the structural transition in the limit of critically damped nuclear motion through coupling of these soft phonon modes to a manifold of surface and interface phonons that arise from the symmetry breaking at the silicon surface. This finding demonstrates that carefully tuned electronic excitations can create non-equilibrium potential energy surfaces that drive structural dynamics at interfaces in the quantum limit (that is, in a regime in which the nuclear motion is directed and deterministic). This technique could potentially be used to tune the dynamic response of a solid to optical excitation, and has widespread potential application, for example in ultrafast detectors.

2.
Hosp Pharm ; 56(6): 792-796, 2021 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-34732940

RESUMO

Introduction: Geriatric patients receiving total knee arthroplasty (TKA) are found to have similar postoperative complications, functional scores, and perioperative mortality, as compared to younger patients. Conversely, geriatric patients often have longer lengths of stay. Periarticular injection (PAI) of liposomal bupivacaine (LB) as part of the multimodal pain management strategy is thought to improve recovery, however, mixed comparative efficacy data exists for its use in TKA.2-5. Methods: A retrospective, chart review was conducted at a 287-bed community teaching hospital. Orthopedic surgical patients who received an infiltration with liposomal bupivacaine versus bupivacaine HCl for unilateral TKA were compared. Patients identified in the electronic medical record by Diagnosis Related Group (DRG) 470-major joint replacement or reattachment of lower extremity without major complication or comorbidity codes were utilized. Patients who meet the following criteria were included: age 65 and older who underwent a TKA between 8/1/2018 to 7/31/2019 were discharged to home. Patients who have contraindications or hypersensitivity to bupivacaine formulations or a history of opioid dependence were excluded. The primary outcome is to identify whether patients who received an infiltration with liposomal bupivacaine had a lower total opioid consumption during their hospital stay. Results: A total of 114 patients who had a DRG 470 code and were above the age of 65 years were studied. There was no statistically significant difference in mean total opioid consumption (oral morphine equivalents) between the bupivacaine HCl (n = 25) and liposomal groups (n = 85) respectively, 93.76 versus 83.72 mg; P = .569. In addition, patients in both groups had similar lengths of hospital stay, 2.5 versus 3 days; P = .529 and mean pain scores until discharge 3.7 versus 4.34 on VAS; P = .305. Conclusion: The results of this drug utilization evaluation do not support a strong clinical advantage with local infiltration of liposomal bupivacaine over bupivacaine HCl in geriatric patients undergoing primary TKA surgery at this institution. There was not a statistically significant difference in mean total opioid consumption between the 2 groups. Additionally, the use of non-opioid analgesics, mean pain scores, and hospital lengths of stay were similar in both groups.

5.
Craniomaxillofac Trauma Reconstr ; 17(1): 74-86, 2024 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-38371216

RESUMO

Study Design: Systematic review and meta-analysis. Objective: The clinical decision to pursue harmonic scalpel (HS) method vs conventional hemostasis to treat head and neck cancers has been arguably predicated on the clinical outcomes observed. This study aims to evaluate the surgical outcomes of neck dissection between both techniques and perform an updated meta-analysis using the available literature. Methods: We searched PubMed, Scopus, and Cochrane Library through 31st December 2021, according to Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) guidelines. Outcome metrics included operative time and intraoperative blood loss. Secondary outcomes consisted of length of hospital stay, length of drain stay, total drain output, and postoperative complications. A meta-analysis was conducted using Review Manager Version 5.3 (RevMan) software employing the Random Effects Model. Results: We identified 114 articles, out of which 10 randomized control trials (RCTs) analyzing a combined total of 558 patients met the inclusion criteria after title and full-text screening. Meta-analysis shows the group treated with HS had a significantly shorter operative time. [MD = -23.21, 95% CI (-34.30, -12.12) P value <.0001 I2 = 92%] but an insignificant lesser intraoperative blood loss [MD = -61.53, 95% CI (-88.61, -34.45) P < .00001 I2 = 79%]. Conclusions: This study confirms that that HS use in neck dissection yields a reduced operative time and intra operative blood loss relative to conventional hemostasis. Furthermore, our paper shows no superiority of HS method over conventional hemostasis where length of hospital stays, length of drain stays, and postoperative complications are concerned. Future RCTs with high-level evidence may further elucidate the relative effectiveness of HS method over conventional hemostasis in treating head and neck cancers.

6.
Am J Infect Control ; 51(5): 582-593, 2023 05.
Artigo em Inglês | MEDLINE | ID: mdl-36007670

RESUMO

OBJECTIVE: To evaluate the safety and efficacy of COVID-19 vaccines in pregnant women performing an updated meta-analysis. METHODS: We searched PubMed, Cochrane Central, and SCOPUS from inception to March 2022. Outcomes of interest were incidence of adverse maternal, fetal and neonatal consequences pertaining to safety of the vaccines. Secondarily, we analyzed the number of SARS-CoV-2 infections, hospitalization for COVID-19, and admission to the I.C.U. for COVID-19 assessing the effectiveness of vaccines. Results were pooled using a random effects model. RESULTS: Ten observational studies (n=326,499) analyzing pregnant women were included. Our results suggest that COVID-19 vaccination prevents infection (OR: 0.56, 95% CI: 0.47, 0.67; P = <0.00001) and related hospitalizations (OR: 0.50, 95% CI: 0.31, 0.82; P = 0.006) effectively. It was also observed that vaccination does not change adverse outcomes in pregnancy, namely preeclampsia or eclampsia, stroke (four weeks of delivery), meconium-stained amniotic fluid, spontaneous vaginal delivery, operative vaginal delivery, cesarean delivery, postpartum hemorrhage, and blood transfusions. Furthermore, the vaccine was observed to be protective against neonatal COVID-19 I.C.U. admissions (OR: 0.85; 95% CI: 0.81, 0.90; P = <0.00001). CONCLUSION: Our pooled analysis suggests that the COVID-19 vaccination in pregnant women prevents infection effectively and has no adverse outcomes. Future large-scale trials in a randomized fashion are needed to confirm our results.


Assuntos
Vacinas contra COVID-19 , COVID-19 , Recém-Nascido , Gravidez , Feminino , Humanos , Vacinas contra COVID-19/efeitos adversos , COVID-19/prevenção & controle , SARS-CoV-2 , Parto Obstétrico , Cesárea
7.
Clin Res Hepatol Gastroenterol ; 47(5): 102111, 2023 05.
Artigo em Inglês | MEDLINE | ID: mdl-36931466

RESUMO

BACKGROUND: The pharmacologic treatment of non-alcoholic fatty liver disease (NAFLD) remains unclear. METHODS: Two reviewers searched PubMed, SCOPUS, Cochrane Central and clinicaltrials.gov for randomized controlled trials (RCTs) of patients with NAFLD with or without type 2 diabetes mellitus (T2DM) receiving TZDs vs SGLT2 inhibitors. The primary outcomes were change in alanine aminotransferase (ALT), aspartate aminotransferase (AST) and gamma-glutamyl transferase (GGT) and improvement in steatosis and fibrosis. The secondary outcomes were changes in lipid profile, body weight and glycated hemoglobin (HbA1c). Random effects models with continuous outcomes as weighted mean differences (WMD) with 95% confidence intervals (CI) were used. RESULTS: Five studies (n = 311 NAFLD patients) were included. Patients treated with SGLT2 inhibitors (n = 156) showed significant decrease in visceral fat area (VFA; WMD 23.45, p < 0.00001) and body weight (WMD 4.22, p < 0.00001) as compared to those treated with TZDs (n = 155). Patients from both groups showed improvement in AST (WMD 1.21, p = 0.40), ALT (WMD -0.46, p = 0.81), GGT (WMD -0.47, p = 0.84), hepatic fibrosis (WMD 0.11, p = 0.52), LDL (WMD 2.19, p = 0.35), HbA1c (WMD -0.16%, p = 0.20), HOMA-IR (WMD: -0.04, p = 0.91) and FPG (WMD -7.37, p = 0.28) which was equivalent and non-significant. CONCLUSION: The improvement in liver enzymes, steatosis and fibrosis caused by SGLT2 inhibitors and TZDs was similar. SGLT2 inhibitors, however, resulted in a significant decrease in VFA and body weight. As weight loss is found to have a positive effect on the resolution of steatosis and fibrosis in NAFLD patients, SGLT2 inhibitors may have the potential to be considered for long-term management, however, further research needs to be conducted to determine the utility of SGLT2 inhibitor class of antidiabetic drugs for effectively treating NAFLD.


Assuntos
Diabetes Mellitus Tipo 2 , Hepatopatia Gordurosa não Alcoólica , Inibidores do Transportador 2 de Sódio-Glicose , Tiazolidinedionas , Humanos , Hepatopatia Gordurosa não Alcoólica/tratamento farmacológico , Hepatopatia Gordurosa não Alcoólica/complicações , Inibidores do Transportador 2 de Sódio-Glicose/uso terapêutico , Hemoglobinas Glicadas , Tiazolidinedionas/uso terapêutico , Diabetes Mellitus Tipo 2/complicações , Diabetes Mellitus Tipo 2/tratamento farmacológico , Peso Corporal , Fibrose , Glucose/uso terapêutico , Sódio/uso terapêutico
8.
Cureus ; 14(4): e24054, 2022 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-35573526

RESUMO

Transcatheter aortic valve replacement (TAVR) is a technique that can be performed through multiple approaches, and the benefits of one approach over another are still being evaluated to make sure patients receive the best possible care. Our meta-analysis aims to compare clinical and procedural outcomes of the transaxillary (TAx) and transaortic (TAo) approaches to validate the more optimal procedure. The systematic literature search was done via PubMed/MEDLINE, Embase, and the Cochrane Central databases from inception to December 2021, to identify articles reporting data on both TAx TAVR and TAo TAVR. In addition, we checked ClinicalTrials.gov for more published or unpublished trials. Baseline patient characteristics, procedure results, and clinical results were extracted from the article and pooled for analysis. A quantitative meta-analysis was conducted using Review Manager (RevMan) version 5.3 (Nordic Cochrane Centre, The Cochrane Collaboration, Copenhagen, Denmark). The outcomes extracted included blood transfusion, conversion to sternotomy, tamponade, contrast amount, procedure time, bleeding incidents (minor, major, or life-threatening), length of stay (LOS), vascular complications (minor or major), acute kidney injury (AKI), paravalvular leak (PVL), permanent pacemaker (PPM) implantation, 30-day mortality, one-year mortality, 30-day stroke, and device success. The final analysis included 11 articles, consisting of 10 observational studies and a pivotal trial. Cumulative results revealed that the TAo approach had a significantly lower incidence of vascular complications (RR = 2.30; 95% CI = 1.22 to 4.35), and the need for implantation of a permanent pacemaker (RR = 1.82; 95% CI = 1.30 to 2.54) along with a lower amount of contrast (mean difference (MD) = 27.40; 95% CI = 3.73 to 51.08) needed to be used. The TAx group was associated with a significantly lower 30-day mortality (RR = 0.46; 95% CI = 0.31 to 0.69), AKI (RR = 0.47; 95% CI = 0.33 to 0.67), and length of hospital stay (MD = -1.95; 95% CI = -2.51 to -1.38). No significant difference was observed between the outcomes of 30-day stroke (RR = 1.38; 95% CI = 0.81 to 2.33), PVL (RR = 1.05; 95% CI = 0.50 to 2.18), tamponade (RR = 0.71; 95% CI = 0.12 to 4.03), conversion to sternotomy (RR = 0.51; 95% CI = 0.06 to 4.30), device success (RR = 0.97; 95% CI = 0.88 to 1.07), the incidence of bleeding (RR = 0.75; 95% CI = 0.51 to 1.10), and procedure time (MD = 4.44; 95% CI = -96.30 to 105.17). Both the procedures were associated with their benefits and risks. Although most of the outcomes favored TAx transcatheter aortic valve implantation (TAVI), it is too early to say if it would be better than TAo TAVI. To authenticate the findings concluded in this meta-analysis and further improve our understanding of the efficacy, safety, and risk profile between TAx and TAo approaches for TAVI, large sample randomized clinical trials are required on a wide scale.

9.
Cureus ; 13(2): e13133, 2021 Feb 04.
Artigo em Inglês | MEDLINE | ID: mdl-33728149

RESUMO

Among the various types of cancer, pancreatic cancer is considered to have a particularly grim prognosis. Treatment includes surgery, chemotherapy, or both. While the role of immunotherapy is well-studied in many types of cancer, such is not the case with pancreatic cancer. A 49-year-old female presented to the oncology clinic following a biopsy of a pancreatic mass. CT-guided needle biopsy of the mass demonstrated moderately differentiated pancreatic adenocarcinoma. Positive emission tomography-computed tomography (PET-CT) revealed metastases to the liver. She was started on chemotherapy with FOLFIRINOX (leucovorin calcium, 5-fluorouracil, irinotecan hydrochloride, oxaliplatin) and demonstrated over 60% reduction in the size of liver metastases within three months. PET-CT four months after initiation of chemotherapy revealed no focal avid fluorodeoxyglucose (FDG) uptake in the liver, and the pancreatic body mass was stable in size at 3.0 cm with stable standardized uptake value (SUV) max at 2.4, only slightly elevated from 1.9 on the previous scan. Further treatment with chemotherapy was halted after 18 cycles due to side effects. With the patient's tumor being epidermal growth factor receptor (EGFR) negative, mismatch repair (MMR) negative, 3% tumor cells PD-L1 positive with 10% tumor-associated immune cells positive, treatment with pembrolizumab was started. Follow-up PET-CTs over the next several months confirmed the patient was in complete remission from metastatic pancreatic cancer. At the time of the report, the patient had a durable response of three years. We report a rare case of complete remission of metastatic pancreatic adenocarcinoma treated with chemotherapy, followed by immunotherapy. With emerging targets for modification of tumor microenvironment, immunotherapy must be further explored in the treatment of pancreatic cancer.

10.
Cureus ; 10(6): e2858, 2018 Jun 22.
Artigo em Inglês | MEDLINE | ID: mdl-30148011

RESUMO

BACKGROUND: Rheumatic diseases are referred to as conditions affecting joints, muscles, ligaments, tendons, and bones. According to a report by World Health Organization, rheumatic and musculoskeletal diseases were labeled as the second most reported cause of disability around the globe. The purpose of this study was to estimate the prevalence of rheumatic diseases in a tertiary care hospital of Karachi; additionally, associations with age groups, gender and comorbidities were obtained as well. METHODS: A cross-sectional study was conducted at the Orthopedic Out Patient Department (OPD) of Dr. Ruth KM Pfau Civil Hospital, Karachi over a span of three months in 2018 (February till May). All 346 patients were follow-up diagnosed cases in the age range of 11-90 years, divided into groups of adolescents, young adults, adults, and older adults. The subjects were questioned about their symptoms, duration of illness, presence of comorbidities, genetic background and the therapy they are undergoing along with compliance. Simple statistical analysis of frequency was done, whereas chi-square test was applied to study associations with gender, age groups, and comorbidities. RESULTS: During the study period, a total of 2000 patients visited the orthopedic OPD, 346 of which were diagnosed cases of rheumatic diseases, yielding a prevalence of 17.3%. The mean age of rheumatic patients who partook in the study was 46.15 ± 15.49 (Range: 12 - 84). Osteoarthritis was recorded as the most prevalent condition, followed by non-specific low back pain and rheumatoid arthritis. Osteoarthritis was statistically significant in young adults, adults, and older adults, while non-specific low back pain had significant associations with gender, young adults, and adults. Diabetes was significantly associated with osteoarthritis, non-specific low back pain, shoulder pain syndrome and psoriatic arthritis, while hypertension significantly co-existed with systemic lupus erthematosus. CONCLUSION: Rheumatic diseases constitute a major disease burden in almost all of the age groups, especially in young patients (18-40 years) within our setup.

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