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1.
Bioresour Technol ; : 131058, 2024 Jul 04.
Artículo en Inglés | MEDLINE | ID: mdl-38971389

RESUMEN

Previous research on Char reactions with gas phase compounds under micro-thermogravimetry systems shows that hydrogen inhibits heterogeneous char reactions. However, its impact on larger gasification systems with evolving hydrogen profiles remains largely unexplored. This study examines a macro-scale wood char bed to understand the influence of in-situ evolving hydrogen on char reactions. When subjected to a specific steam flux, carbon conversion and pore morphology changes are mainly confined to the bed's upstream, with the downstream char retaining its original characteristics. Numerical investigations reveal over 75% of species production and consumption occurs within the initial 20% of bed height. Fourier-transform infrared spectroscopy confirms hydrogen-induced inhibition in downstream segments, showing a shift from C-OH to C-H bonds. Particle-scale analysis indicates significantly higher rates of hydrogen diffusion and adsorption compared to H2O, impeding downstream C+H2O reactions. Increased temperature, higher reactant concentrations, or reduced residence time can overcome this inhibition, enhancing conversion rates. These findings are critical for optimizing steam-to-biomass ratios in oxy-steam gasification systems for generating hydrogen-rich syngas.

2.
Artículo en Inglés | MEDLINE | ID: mdl-38748901

RESUMEN

INTRODUCTION: The Walch classification has been widely accepted and further developed as a method to characterize glenohumeral arthritis. However, many studies have reported low and inconsistent measures of the reliability of the Walch classification. The purpose of this study was to review the literature on the reliability of the Walch classification and characterize how imaging modality and classification modifications affect reliability. METHODS: A systematic review of publications that included reliability of the Walch classification reported through intraobserver and interobserver kappa values was conducted. A search in January 2021 and repeated in July 2023 used the terms ["Imaging" OR "radiography" OR "CT" OR "MRI"] AND ["Walch classification"] AND ["Glenoid arthritis" OR "Shoulder arthritis"]. All clinical studies from database inception to July 2023 that evaluated the Walch or modified Walch classification's intraobserver and/or interobserver reliability were included. Cadaveric studies and studies that involved subjects with previous arthroplasty, shoulder débridement, glenoid reaming, interposition arthroplasty, and latarjet or bankart procedure were excluded. Articles were categorized by imaging modality and classification modification. RESULTS: Thirteen articles met all inclusion criteria. Three involved the evaluation of plain radiographs, 10 used CT, two used three-dimensional (3D) CT, and four used magnetic resonance imaging. Nine studies involved the original Walch classification system, five involved a simplified version, and four involved the modified Walch. Six studies examined the reliability of raters of varying experience levels with none reporting consistent differences based on experience. Overall intraobserver reliability of the Walch classifications ranged from 0.34 to 0.92, and interobserver reliability ranged from 0.132 to 0.703. No consistent trends were observed in the effect of the imaging modalities or classification modifications on reliability. DISCUSSION: The reliability of the Walch classification remains inconsistent, despite modification and imaging advances. Consideration of the limitations of the classification system is important when using it for treatment or prognostic purposes.

3.
J Phys Chem Lett ; 15(19): 5171-5176, 2024 May 16.
Artículo en Inglés | MEDLINE | ID: mdl-38713476

RESUMEN

Exciton-plasmon coupling is a fascinating physical phenomenon that has been investigated in various metal semiconductor systems. Intentionally chosen silicon nanowires (SiNWs) systems act as a host material for providing exciton as well as silicon oxide as a thin dielectric. A clear blue-shift in photoluminescence (PL) peak and a significant increase in visible range absorption were observed for metal nanoparticle (MNP) decorated SiNWs (D-SiNWs) which signifies the presence of exciton-plasmon coupling. A further investigation reveals that the possibility of the occurrence of the plasmon-induced resonance energy transfer (PIRET) mechanism is higher. The PL intensity enhancement in Au-decorated SiNWs is higher (∼38 times) in comparison to that in Pt due to the presence of a strong and localized electric field of plasmons near the interface of metal and semiconductors. Moreover, splitting in PL for gold-decorated SiNWs might be due to the presence of dipole-quadrupole coupling along with dipole-dipole coupling, which further increases the strength of the PIRET mechanism.

4.
Cryo Letters ; 45(4): 212-220, 2024.
Artículo en Inglés | MEDLINE | ID: mdl-38809785

RESUMEN

BACKGROUND: Cryopreservation of spermatozoa involves reduction of temperature to a subzero level, leading to increased longevity. However, temperature reduction has a significant effect on sperm membranes. OBJECTIVE: To evaluate the impact of the rate of temperature drop during the first phase of freezing on subtle membrane changes in cryopreserved bull spermatozoa. MATERIALS AND METHODS: Thirty-two ejaculates from four bulls (eight ejaculates/bull) were collected using artificial vagina while keeping a 3 to 4 days gap between two collections. Diluted semen samples were equilibrated at 5 degree C for 4 hours. The samples were then placed in a pre-programmed semen freezer. The first phase of freezing, that is, 5 degree C till -10 degree C was subjected to three different temperature drop rates: accelerated (F1), moderate (F2), and slow (F3), at 20 degree C per min, 10 degree C per min and 5 degree C per min, respectively. After thawing, spermatozoa were assessed for percentage live, plasma, and acrosomal membrane integrity, along with the external appearance of phosphatidyl serine, indicating apoptosis. RESULTS: A significant difference (p < 0.05) in viability, plasma membrane integrity (HOS test), and acrosome membrane integrity (PSA test) was observed between F3 and the other groups. However, the parameters did not significantly differ between F1 and F2. The annexin V-PI assay (AN/PI) categorized four types of sperm populations: non-apoptotic and viable (AN-/PI-), apoptotic and viable (AN+/PI-), non-apoptotic and non-viable (AN-/PI+), and apoptotic and non-viable (AN+/PI+). The proportion of spermatozoa with (AN-/PI-) and (AN+/PI+) differed significantly (p < 0.05) between F3 and the other groups. The values for apoptotic and viable (AN+/PI-) and non-apoptotic and non-viable (AN-/PI+) sperm were not significantly different among all freezing categories. CONCLUSION: A slower temperature drop rate (freezing rate) during the first phase of freezing results in less damaging, subtle membrane changes. Doi.org/10.54680/fr24410110312.


Asunto(s)
Membrana Celular , Criopreservación , Preservación de Semen , Espermatozoides , Masculino , Animales , Criopreservación/métodos , Criopreservación/veterinaria , Bovinos , Espermatozoides/fisiología , Espermatozoides/citología , Preservación de Semen/métodos , Preservación de Semen/veterinaria , Membrana Celular/fisiología , Congelación , Temperatura , Supervivencia Celular , Apoptosis , Acrosoma
5.
Indian J Crit Care Med ; 28(4): 349-354, 2024 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-38585325

RESUMEN

Introduction: The usual methods of perfusion assessment in patients with shock, such as capillary refill time, skin mottling, and serial serum lactate measurements have many limitations. Veno-arterial difference in the partial pressure of carbon dioxide (PCO2 gap) is advocated being more reliable. We evaluated serial change in PCO2 gap during resuscitation in circulatory shock and its effect on ICU outcomes. Materials and methods: This prospective observational study included 110 adults with circulatory shock. Patients were resuscitated as per current standards of care. We recorded invasive arterial pressure, urine output, cardiac index (CI), PCO2 gap at ICU admission at 6, 12, and 24 hours, and various patient outcomes. Results: Significant decrease in PCO2 gap was observed at 6 h and was accompanied by improvement in serum lactate, mean arterial pressure, CI and urine output in (n = 61). We compared these patients with those in whom this decrease did not occur (n = 49). Mortality and ICU LOS was significantly lower in patients with low PCO2 gap, while more patients with high PCO2 gap required RRT. Conclusion: We found that a persistently high PCO2 gap at 6 and 12 h following resuscitation in patients with shock of various etiologies, was associated with increased mortality, need for RRT and increased ICU LOS. High PCO2 gap had a moderate discriminative ability to predict mortality. How to cite this article: Zirpe KG, Tiwari AM, Kulkarni AP, Vaidya HS, Gurav SK, Deshmukh AM, et al. The Evolution of Central Venous-to-arterial Carbon Dioxide Difference (PCO2 Gap) during Resuscitation Affects ICU Outcomes: A Prospective Observational Study. Indian J Crit Care Med 2024;28(4):349-354.

6.
Cureus ; 16(3): e55676, 2024 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-38586684

RESUMEN

Chiari malformation (CM) type 1 is a complex neurological disorder characterized by the displacement of the cerebellar tonsils into the upper spinal canal. Hydrosyringomyelia (HSM), which frequently coexists with this condition, presents diagnostic and treatment problems due to its broad spectrum of symptoms. There are various forms of CMs, with CM type 1 (CM1) being the most common type. Magnetic resonance imaging (MRI) is the best imaging technique to properly identify and diagnose CM1 and HSM. Important imaging findings include downward displacement of the cerebellar tonsils across the foramen magnum, the appearance of the syrinx in the spinal cord, and the alteration of the flow dynamics of the cerebrospinal fluid. This study was conducted at Datta Meghe Medical College, Nagpur, and Government Medical College & Super Speciality Hospital, Nagpur, India. It focuses on the diagnostic use of MRI in CM1 and its variations associated with HSM. Individuals who are asymptomatic may not need any treatment; however, those who are symptomatic or have HSM may require surgical decompression and restoration of the flow. We discuss the findings of MRI of six cases of CM1 and its variants with HSM and search for possible underlying causes. We conclude that magnetic resonance imaging is an imaging modality for the identification and evaluation of CM1 in cases of HSM.

7.
Artículo en Inglés | MEDLINE | ID: mdl-38642875

RESUMEN

BACKGROUND: Prior research has shown that industry funding can impact the outcomes reported in medical literature. Limited data exist on the degree of bias that industry funding may have on shoulder arthroplasty literature outside of the Journal of Shoulder and Elbow Surgery. The purpose of this study is to characterize the type and frequency of funding for recently published shoulder arthroplasty studies and the impact of industry funding on reported outcomes. We hypothesized that studies with industry funding are more likely to report positive outcomes than those without. MATERIALS AND METHODS: We performed a retrospective study searching all articles with the term "shoulder arthroplasty," "reverse shoulder arthroplasty," "anatomic total shoulder arthroplasty," or "total shoulder arthroplasty" on PubMed from the years January 2020 to December 2022. The primary outcome of studies was coded as either positive, negative, or neutral. A positive result was defined as one in which the null hypothesis was rejected. A negative result was defined as one in which the result did not favor the group in which the industry-funded implant was used. A neutral result was defined as one in which the null hypothesis was confirmed. Article funding type, subcategorized as National Institutes of Health funding or industry funding was recorded. Author disclosures were recorded to determine conflicts of interest. Statistical analysis was conducted using the χ2 test and Fisher exact test. RESULTS: A total of 750 articles reported on either conflict of interest or funding source and were included in the study. Of the total number of industry-funded studies, the majority were found to have a positive primary endpoint (58.1%, 104 of 179), as compared to a negative (7.8%, 14 of 179) or neutral endpoint (33.5%, 60 of 179) (P = .004). Overall, 363 articles reported an author conflict of interest, and the majority of these studies had positive primary endpoint (55.6%, 202 of 363) as compared to negative (9.1%, 33 of 363) or neutral endpoints (34.4%, 125 of 363) (P = .002). CONCLUSION: The results of this study suggest that there is a significant relationship between conflicts of interest and the primary outcome of shoulder arthroplasty studies, beyond the overall positive publication bias. Studies with industry funding and author conflicts of interest both report positive outcomes more frequently than negative outcomes. Shoulder surgeons should be aware of this potential bias when choosing to base clinical practice on published data.

8.
Spectrochim Acta A Mol Biomol Spectrosc ; 315: 124232, 2024 Jul 05.
Artículo en Inglés | MEDLINE | ID: mdl-38593538

RESUMEN

The present study aims to identify spermatogenesis in testicular seminiferous tubules (ST) and testicular tissue of adult normal and busulfan-treated mice utilizing PCA and Raman spectroscopy. Raman measurements were conducted on single tubules and testes samples from adult and immature mice, comparing them with those from busulfan-treated adult mice, with validation through histological examination. The analysis revealed a higher signal variability (30 %-40 % at the peaks), prompting scrutiny of individual Raman spectra as a means of spermatogenesis measurement. However, principal component analysis (PCA) demonstrated significant cluster separation between the ST of mature and immature mice. Similar investigations were performed to compare ST from normal mature mice and those from busulfan-treated (BS-treated) mature mice, revealing substantial separation along PC1 and PC2 for all comparison sets. Additionally, comparing testicular samples from mature and immature mice revealed distinct separation in PCA. The study concludes that the combined approach of PCA and Raman spectroscopy proves to be a noninvasive and potentially valuable method for identifying spermatogenesis in seminiferous tubules and testicular samples.


Asunto(s)
Busulfano , Análisis de Componente Principal , Túbulos Seminíferos , Espectrometría Raman , Espermatogénesis , Testículo , Animales , Espectrometría Raman/métodos , Masculino , Espermatogénesis/efectos de los fármacos , Espermatogénesis/fisiología , Túbulos Seminíferos/efectos de los fármacos , Testículo/efectos de los fármacos , Ratones
9.
Artículo en Inglés | MEDLINE | ID: mdl-38500477

RESUMEN

CONTEXT: Long-term glucocorticoid levels in scalp hair (HairGCs), including cortisol and the inactive form cortisone, represent the cumulative systemic exposure to glucocorticoids over months. HairGCs have repeatedly shown associations with cardiometabolic and immune parameters, but longitudinal data are lacking. DESIGN: We investigated 6341 hair samples of participants from the Lifelines cohort study for cortisol and cortisone levels, and associated these to incident cardiovascular diseases (CVD) during 5-7 years of follow-up. We computed the odds ratio (OR) of HairGC levels for incident CVD via logistic regression, adjusting for classical cardiovascular risk factors, and performed a sensitivity analysis in subcohorts of participants <60 years and >= 60 years. Also, we associated HairGC levels to immune parameters (total leukocytes and subtypes). RESULTS: Hair cortisone levels (available in n = 4701) were independently associated with incident CVD (p < 0.001), particularly in younger individuals (multivariate-adjusted OR 4.21, 95% confidence interval (CI) 1.91-9.07 per point increase in 10-log cortisone concentration (pg/mg), p < 0.001). All immune parameters except eosinophils were associated with hair cortisone (all multivariate-adjusted p < 0.05). CONCLUSIONS: In this large, prospective cohort study, we found that long-term cortisone levels, measured in scalp hair, represent a relevant and significant predictor for future cardiovascular diseases in younger individuals. These results highlight glucocorticoid action as possible treatment target for CVD prevention, where hair glucocorticoid measurements could help identify individuals that may benefit from such treatments.

10.
JSES Int ; 8(1): 232-235, 2024 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-38312284

RESUMEN

Background: The split anconeus fascia transfer (SAFT) is an option for reconstruction of the lateral ulnar collateral ligament (LUCL) in chronic posterolateral rotatory instability (PLRI) of the elbow with potential advantages of using only local tissue within the surgical exposure and not requiring ulnar fixation. This study aimed to assess SAFT strength compared to a traditional free graft reconstruction in a PLRI biomechanical model. Methods: To measure biomechanical strength, eight cadaveric upper extremity pairs were utilized. Within each pair, one specimen was randomly assigned to LUCL reconstruction with autograft palmaris longus and the other to SAFT reconstruction. Torque load to failure was assessed on a load frame with the elbow in 30 degrees of flexion, 5 degrees of valgus, and 25 N axial load as the elbow was brought into external rotation. Torque load to failure was compared between the two reconstruction techniques. Results: No difference was found in the torque load to failure between SAFT specimens compared to palmaris longus autograft specimens (mean 14.6 ± 4.4 Nm vs. mean 11.3 ± 3.9 Nm; P = .16). Discussion: In this biomechanical study, the SAFT LUCL reconstruction provided torque load to failure similar to that of the traditional technique. These findings suggest that the SAFT technique warrants continued study as a biomechanically sound option for LUCL reconstruction in the setting of elbow PLRI.

11.
3 Biotech ; 14(2): 56, 2024 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-38298555

RESUMEN

A large seed mutant, TG 89 having a 76.7% increment in hundred kernel weight in comparison to its parent TG 26, was isolated from an electron beam-induced mutagenized population. Studies based on environmental scanning electron microscopy of both parent and mutant revealed that the mutant seed cotyledon had significantly bigger cell size than parent. A mapping population with 122 F2 plants derived from the mutant and a distant normal seed genotype (ICGV 15007) was utilized to map the QTL associated with higher HKW. Bulk segregant analysis revealed putative association of three markers with this mutant large seed trait. Further, genotyping of F2 individuals with polymorphic markers detected 14 linkage groups with a map distance of 1053 cM. QTL analysis revealed a significant additive major QTL for the mutant large seed trait on linkage group A05 explaining 12.7% phenotypic variation for the seed size. This QTL was located between flanking markers AhTE333 and AhTE810 having a map interval of 4.7 cM which corresponds to 90.65 to 107.24 Mbp in A05 chromosome, respectively. Within this genomic fragment, an ortholog of the BIG SEEDS 1 gene was found at 102,476,137 bp. Real-time PCR revealed down-regulation of this BIG SEEDS 1 gene in the mutant indicating a loss of function mutation giving rise to a large seed phenotype. This QTL was validated in 11 advanced breeding lines having large seed size from this mutant but with varied genetic backgrounds. This validation showcased a highly promising selection accuracy of 90.9% for the marker-assisted selection. Supplementary Information: The online version contains supplementary material available at 10.1007/s13205-023-03909-0.

13.
J Shoulder Elbow Surg ; 33(7): 1465-1472, 2024 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-38182025

RESUMEN

BACKGROUND: Particle-induced osteolysis resulting from polyethylene wear remains a source of implant failure in anatomic total shoulder designs. Modern polyethylene components are irradiated in an oxygen-free environment to induce cross-linking, but reducing the resulting free radicals with melting or heat annealing can compromise the component's mechanical properties. Vitamin E has been introduced as an adjuvant to thermal treatments. Anatomic shoulder arthroplasty models with a ceramic head component have demonstrated that vitamin E-enhanced polyethylene show improved wear compared with highly cross-linked polyethylene (HXLPE). This study aimed to assess the biomechanical wear properties and particle size characteristics of a novel vitamin E-enhanced highly cross-linked polyethylene (VEXPE) glenoid compared to a conventional ultrahigh-molecular-weight polyethylene (UHMWPE) glenoid against a cobalt chromium molybdenum (CoCrMo) head component. METHODS: Biomechanical wear testing was performed to compare the VEXPE glenoid to UHMWPE glenoid with regard to pristine polyethylene wear and abrasive endurance against a polished CoCrMo alloy humeral head in an anatomic shoulder wear-simulation model. Cumulative mass loss (milligrams) was recorded, and wear rate calculated (milligrams per megacycle [Mc]). Under pristine wear conditions, particle analysis was performed, and functional biologic activity (FBA) was calculated to estimate particle debris osteolytic potential. In addition, 95% confidence intervals for all testing conditions were calculated. RESULTS: The average pristine wear rate was statistically significantly lower for the VEXPE glenoid compared with the HXLPE glenoid (0.81 ± 0.64 mg/Mc vs. 7.00 ± 0.45 mg/Mc) (P < .05). Under abrasive wear conditions, the VEXPE glenoid had a statistically significant lower average wear rate compared with the UHMWPE glenoid comparator device (18.93 ± 5.80 mg/Mc vs. 40.47 ± 2.63 mg/Mc) (P < .05). The VEXPE glenoid demonstrated a statistically significant improvement in FBA compared with the HXLPE glenoid (0.21 ± 0.21 vs. 1.54 ± 0.49 (P < .05). CONCLUSIONS: A new anatomic glenoid component with VEXPE demonstrated significantly improved pristine and abrasive wear properties with lower osteolytic particle debris potential compared with a conventional UHMWPE glenoid component. Vitamin E-enhanced polyethylene shows early promise in shoulder arthroplasty components. Long-term clinical and radiographic investigation needs to be performed to verify if these biomechanical wear properties translate to diminished long-term wear, osteolysis, and loosening.


Asunto(s)
Artroplastía de Reemplazo de Hombro , Ensayo de Materiales , Polietilenos , Diseño de Prótesis , Falla de Prótesis , Prótesis de Hombro , Vitamina E , Humanos , Artroplastía de Reemplazo de Hombro/métodos , Fenómenos Biomecánicos , Tamaño de la Partícula , Osteólisis/etiología , Osteólisis/prevención & control , Articulación del Hombro/cirugía
14.
Artículo en Inglés | MEDLINE | ID: mdl-38237720

RESUMEN

BACKGROUND: Reducing differences in the gender representation of shoulder arthroplasty surgeons may help optimize patient care. This work aimed to determine (1) the current gender distribution of surgeons performing shoulder arthroplasty, (2) how gender relates to practice patterns among shoulder arthroplasty surgeons, and (3) how gender distribution has been changing over time. METHODS: The Medicare Provider Utilization and Payment Data for the years 2012-2020 were used to identify orthopedic surgeons performing anatomic and reverse total shoulder arthroplasty (Current Procedural Terminology code 23472). The data set provides self-reported gender, credentials, National Provider Identifier, annual volume of all procedures (based on Current Procedural Terminology codes) that were performed ≥11 times in the calendar year, and location for all included providers. The data set was linked to the Medicare Physician Compare data set using National Provider Identifiers to determine hospital affiliations, year of medical school graduation, and graduating medical school. All included hospitals were queried to determine academic status (affiliated orthopedic residency or fellowship program). The American Shoulder and Elbow Surgeons (ASES) directory was reviewed to determine the gender breakdown of current members. RESULTS: The number of surgeons performing ≥11 shoulder arthroplasties annually increased from 821 (13 women [1.6%]) in 2012 to 1840 (53 women [2.9%], P = .05) in 2019. One female surgeon ranked in the top 100 surgeons by shoulder arthroplasty volume in 2012 and in 2020. Female surgeons graduated more recently from medical school (mean, 2005) compared with male surgeons (mean, 1997; P < .001). About 10% of female surgeons (10.8%, 12 of 111) and male surgeons (9.1%, 229 of 2528) practiced at hospitals with orthopedic residents (P = .50). Female surgeons performing shoulder arthroplasty were less likely than male surgeons to perform total knee arthroplasty (29.4% vs. 54.1%, P < .001) and total hip arthroplasty (12.6% vs. 34.7%, P < .001). There were 86 female members of ASES (6.7%, 86 of 1275), with a significant difference in the proportion of women in differing membership categories (P = .017). DISCUSSION AND CONCLUSION: A diverse cohort of high-volume shoulder replacement surgeons is integral to delivering high-quality shoulder arthroplasty. Currently, the proportion of women performing high-volume shoulder replacement in the United States is small, with little improvement in recent years. However, women performing shoulder arthroplasty are younger and are often involved in academic practices, and the membership of ASES is increasingly female. Continued efforts to promote orthopedics-and to mentor female residents and medical students interested in shoulder surgery-may bring real change to the gender differences among shoulder replacement surgeons over the coming years.

15.
ACS Omega ; 9(2): 2060-2079, 2024 Jan 16.
Artículo en Inglés | MEDLINE | ID: mdl-38250394

RESUMEN

Gasification is an advanced thermochemical process that converts carbonaceous feedstock into syngas, a mixture of hydrogen, carbon monoxide, and other gases. However, the presence of tar in syngas, which is composed of higher molecular weight aromatic hydrocarbons, poses significant challenges for the downstream utilization of syngas. This Review offers a comprehensive overview of tar from gasification, encompassing gasifier chemistry and configuration that notably impact tar formation during gasification. It explores the concentration and composition of tar in the syngas and the purity of syngas required for the applications. Various tar removal methods are discussed, including mechanical, chemical/catalytic, and plasma technologies. The Review provides insights into the strengths, limitations, and challenges associated with each tar removal method. It also highlights the importance of integrating multiple techniques to enhance the tar removal efficiency and syngas quality. The selection of an appropriate tar removal strategy depends on factors such as tar composition, gasifier operating and design factors, economic considerations, and the extent of purity required at the downstream application. Future research should focus on developing cleaning strategies that consume less energy and cause a smaller environmental impact.

16.
J Endocrinol ; 260(3)2024 Mar 01.
Artículo en Inglés | MEDLINE | ID: mdl-38224333

RESUMEN

Somatostatin receptors (SSTs) are widely expressed in pituitary tumors and neuroendocrine neoplasms (NENs) of different origins, i.e. the gastrointestinal tract and the thorax (lungs and thymus), thus representing a well-established target for medical treatment with SST ligands (SRLs). However, the response to SRLs is highly heterogeneous between tumors. Two main factors can contribute to this variability: (i) the differential SST expression among tumor types and (ii) the differential expression/modulation of the SST-related intracellular machinery. In this literature review, we provide an overview of available data on the variable expression of SSTs in pituitary tumors and NENs, together with the resulting clinical implications. Moreover, we aim to describe the complex intracellular machinery involved in SST signaling and trafficking. Particularly, we will focus on ß-arrestins and describe their role in receptor internalization and recycling, as well as the various functions of these scaffold molecules in tumor pathogenesis and progression. This review highlights the interplay between membrane receptors and intracellular machinery, together with its role in determining the clinical behavior of the tumor and the response to treatment in patients with pituitary tumors or NENs.


Asunto(s)
Tumores Neuroendocrinos , Neoplasias Hipofisarias , Humanos , Receptores de Somatostatina/metabolismo , Receptores de Somatostatina/uso terapéutico , Neoplasias Hipofisarias/tratamiento farmacológico
17.
J Shoulder Elbow Surg ; 33(2): 321-327, 2024 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-37499785

RESUMEN

BACKGROUND: Lower trapezius tendon transfer is 1 option to improve pain and function with massive irreparable rotator cuff tears. Magnetic resonance imaging (MRI) evaluation of tendon healing with the procedure has not yet been reported. The purpose of this study was to evaluate early tendon transfer healing using postoperative MRI scans and to assess early clinical outcomes in patients after arthroscopically assisted lower trapezius tendon transfer (AALTT) for massive irreparable rotator cuff tears. METHODS: This was a single institution retrospective review of consecutive patients with massive irreparable rotator cuff tears who underwent AALTT with a single surgeon from January 2017 to July 2020 with a minimum 6-month follow-up. Patient information including age, sex, follow-up, prior surgical history, and type of work (sedentary or labor-intensive) was recorded. Preoperative and postoperative range of motion, external rotation strength, presence of a lag sign, and pain visual analog scale data were extracted from medical records. Patient-reported outcomes were extracted from patient charts. Six-month postoperative MRIs were reviewed for tendon transfer healing at both the greater tuberosity and the trapezius-allograft interface. RESULTS: A total of 19 patients met inclusion criteria with average age 56.7 (range, 29-72 years). Of these patients, 17 (89.5%) were male. The average follow-up was 14.6 (range, 6-45) months. Fifteen (78.9%) patients had unsuccessful previous rotator cuff repair. Six-month MRI demonstrated complete healing of the transferred tendon in 17 of 19 patients (89.5%). There were significant improvements in postoperative pain visual analog scale (5.9 ± 2 vs. 1.8 ± 2), ASES score (44.6 ± 18 vs. 71.2 ± 24), and Patient Reported Outcomes Measurement Information System Physical (46.3 ± 6 vs. 51.3 ± 11) and in external rotation motion (10.5 ± 17° vs. 40.5 ± 13°) and strength (2.8/5 ± 1 vs. 4.7/5 ± 0.5) at final follow-up. All patients with a preoperative external rotation lag sign had reversal of their lag sign at final follow-up (15/15). Of 17 work-eligible patients, 13 (76.4%) were able to return to work. CONCLUSION: In this series, AALTT showed a high rate of healing of the transferred tendon on MRI by 6 months postoperatively. The current findings of a high rate of early tendon transfer healing are consistent with the good early and mid-term outcomes that have been observed in AALTT and provide support for surgeon and patient expectations, postoperative rehabilitation, and return to work following AALTT for massive posterior superior rotator cuff tears.


Asunto(s)
Tendón Calcáneo , Lesiones del Manguito de los Rotadores , Músculos Superficiales de la Espalda , Humanos , Masculino , Persona de Mediana Edad , Femenino , Tendón Calcáneo/trasplante , Resultado del Tratamiento , Músculos Superficiales de la Espalda/cirugía , Transferencia Tendinosa/métodos , Estudios Retrospectivos , Rango del Movimiento Articular , Aloinjertos , Dolor/etiología , Artroscopía/métodos
18.
J Shoulder Elbow Surg ; 33(3): 604-609, 2024 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-37777043

RESUMEN

BACKGROUND: Subscapularis function is critical after anatomic total shoulder arthroplasty (aTSA). Recently, however, a technique has been described that features a chevron or V-shaped subscapularis tendon cut (VT). This biomechanical study compared repair of the standard tenotomy (ST), made perpendicular to the subscapularis fibers, to repair of the novel VT using cyclic displacement, creep, construct stiffness, and load to failure. METHODS: This biomechanical study used 6 pairs of fresh frozen paired cadaveric shoulder specimens. One specimen per each pair underwent VT, the other ST. Subscapularis tenotomy was performed 1 cm from the insertion onto the lesser tuberosity. For VT, the apex of the V was 3 cm from the lesser tuberosity. After tenotomy, each humerus underwent humeral head arthroplasty. Eight figure-of-8 sutures were used to repair the tenotomy (Ethibond Excel; Ethicon, US LLC). Specimens were cyclically loaded from 2 to 100 N at 45 degrees abduction at a rate of 1 Hz for 3000 cycles. Cyclic displacement, creep, and stiffness and load to failure were measured. RESULTS: Cyclic displacement did not differ significantly between the ST and VT from 1 to 3000 cycles. The difference in displacement between the V-shaped and standard tenotomy at 3000 cycles was 1.57 mm (3.66 ± 1.55 mm vs. 5.1 ± 2.8 mm, P = .31, respectively). At no point was the V-shape tenotomy (VT) >3 mm of average displacement, whereas the standard tenotomy (ST) averaged 3 mm of displacement after 3 cycles. Creep was significantly lower for VT in cycles 1 through 3. For all cycles, stiffness was not significantly different in the VT group compared with the ST group. Load to failure was not statistically significant in the VT compared to the standard tenotomy throughout all cycles (253.2 ± 27.7 N vs. 213.3 ± 76.04 N; P = .25, respectively). The range of load to failure varied from 100 to 301 N for standard tenotomy compared with 216 to 308 N for VT. CONCLUSION: This study showed that VT and ST demonstrated equivalent stiffness, displacement, and load to failure. VT had the benefit of less creep throughout the first 3 cycles, although there was no difference from cycle 4 to 3000. The VT had equivalent biomechanical properties to the ST at time zero, an important first step in our understanding of the technique. The VT technique warrants further clinical study to determine if the technique has clinical benefits over ST following aTSA.


Asunto(s)
Manguito de los Rotadores , Articulación del Hombro , Humanos , Manguito de los Rotadores/cirugía , Articulación del Hombro/cirugía , Tenotomía/métodos , Fenómenos Biomecánicos , Osteotomía/métodos , Cabeza Humeral , Cadáver
19.
J Shoulder Elbow Surg ; 33(7): 1563-1569, 2024 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-38122889

RESUMEN

BACKGROUND: Home health services provide patients with additional professional care and supervision following discharge from the hospital to theoretically reduce the risk of complication and reduce health care utilization. The aim of this investigation was to determine if patients assigned home health services following total shoulder arthroplasty (anatomic [TSA] and reverse [RSA]) exhibited lower rates of medical complications, lower health care utilization, and lower cost of care compared with patients not receiving these services. METHODS: A national insurance database was retrospectively reviewed to identify all patients undergoing primary TSA and RSA from 2010 to 2019. Patients who received home health services were matched using a propensity score algorithm to a set of similar patients who were discharged home without services. We compared medical complication rates, emergency department (ED) visits, readmissions, and 90-day cost of care between the groups. Multivariate regression analysis was performed to determine the independent effect of home health services on all outcomes. RESULTS: A total of 1119 patients received home health services and were matched to 11,190 patients who were discharged home without services. There was no significant difference in patients who received home health services compared with those who did not receive home health services with respect to rates of ED visits within 30 days (OR 1.293; P = .0328) and 90 days (OR 1.215; P = .0378), whereas the home health group demonstrated increased readmissions within 90 days (OR 1.663; P < .001). For all medical complications, there was no difference between cohorts. Episode-of-care costs for home health patients were higher than those discharged without these services ($12,521.04 vs. $9303.48; P < .001). CONCLUSION: Patients assigned home health care services exhibited higher cost of care and readmission rates without a reduction in the rate of complication or early return to the ED. These findings suggest that home health care services should be strongly analyzed on a case-by-case basis to determine if a patient may benefit from its implementation.


Asunto(s)
Artroplastía de Reemplazo de Hombro , Costos de la Atención en Salud , Servicios de Atención de Salud a Domicilio , Readmisión del Paciente , Complicaciones Posoperatorias , Puntaje de Propensión , Humanos , Masculino , Readmisión del Paciente/estadística & datos numéricos , Readmisión del Paciente/economía , Femenino , Servicios de Atención de Salud a Domicilio/economía , Artroplastía de Reemplazo de Hombro/economía , Estudios Retrospectivos , Anciano , Complicaciones Posoperatorias/economía , Complicaciones Posoperatorias/epidemiología , Complicaciones Posoperatorias/prevención & control , Persona de Mediana Edad
20.
J Am Coll Radiol ; 20(11S): S315-S328, 2023 11.
Artículo en Inglés | MEDLINE | ID: mdl-38040458

RESUMEN

Noncontrast CT (NCCT) is the imaging study of choice for initial evaluation of patients with acute onset of flank pain and suspicion of stone disease without known prior stone disease. NCCT can reliably characterize the location and size of an offending ureteral calculus, identify complications, and diagnose alternative etiologies of abdominal pain. Although less sensitive in the detection of stones, ultrasound may have a role in evaluating for signs of obstruction. Radiography potentially has a role, although has been shown to be less sensitive than NCCT. For patients with known disease and recurrent symptoms of urolithiasis, NCCT remains the test of choice for evaluation. In pregnancy, given radiation concerns, ultrasound is recommended as the initial modality of choice with potential role for noncontrast MRI. In scenarios where stone disease suspected and initial NCCT is inconclusive, contrast-enhanced imaging, either with MRI or CT/CT urogram may be appropriate. The American College of Radiology Appropriateness Criteria are evidence-based guidelines for specific clinical conditions that are reviewed annually by a multidisciplinary expert panel. The guideline development and revision process support the systematic analysis of the medical literature from peer reviewed journals. Established methodology principles such as Grading of Recommendations Assessment, Development, and Evaluation or GRADE are adapted to evaluate the evidence. The RAND/UCLA Appropriateness Method User Manual provides the methodology to determine the appropriateness of imaging and treatment procedures for specific clinical scenarios. In those instances where peer reviewed literature is lacking or equivocal, experts may be the primary evidentiary source available to formulate a recommendation.


Asunto(s)
Dolor Agudo , Urolitiasis , Humanos , Dolor Abdominal , Dolor en el Flanco/diagnóstico por imagen , Dolor en el Flanco/etiología , Imagen por Resonancia Magnética/métodos , Radiografía , Sociedades Médicas , Estados Unidos , Urolitiasis/complicaciones , Urolitiasis/diagnóstico por imagen
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