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1.
BMJ Case Rep ; 17(8)2024 Aug 31.
Artículo en Inglés | MEDLINE | ID: mdl-39216895

RESUMEN

Tarsal coalition is an uncommon cause of insidious-onset foot pain typically affecting adolescents. Cuboid-navicular coalitions are among the rarest variety, comprising less than 1% of all tarsal coalitions. This case report describes a female competitive gymnast in middle childhood with a 6-month history of worsening insidious onset right foot pain that forced withdrawal from all sporting activities. The patient reported a background of intermittent foot pain and bilateral ankle instability over the past 2 years. A comprehensive history and physical examination, alongside MRI, enabled the diagnosis of a fibro-osseous cuboid-navicular coalition. Through early diagnosis, a targeted and prompt trial of non-operative management was implemented, consisting of physiotherapy, a deloading protocol, orthotics and analgesia. At 6-month follow-up, this led to improvements in pain symptoms and functional outcomes as well as a return to competitive sport. Early recognition of cuboid-navicular coalition is essential to prevent early degenerative joint disease.


Asunto(s)
Coalición Tarsiana , Humanos , Femenino , Coalición Tarsiana/diagnóstico por imagen , Coalición Tarsiana/complicaciones , Imagen por Resonancia Magnética , Adolescente , Gimnasia , Atletas , Modalidades de Fisioterapia , Huesos Tarsianos/anomalías , Huesos Tarsianos/diagnóstico por imagen , Volver al Deporte , Niño
2.
Clin Transplant ; 38(7): e15412, 2024 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-39049617

RESUMEN

INTRODUCTION: Frailty and sarcopenia are associated with an increased risk of hospitalization and mortality in patients with end-stage liver disease. The ability to identify frail patients at risk of adverse outcomes could help optimize liver transplant (LT) evaluations and pre-transplant care. This study compared sarcopenia, via L3-psoas muscle index (L3-PMI), to frailty, via liver frailty index (LFI) and analyzed associated outcomes after liver transplantation (LT). METHODS: A retrospective review of consecutive LT-recipients with cross-sectional abdominal/pelvic imaging were reviewed over 5 years at a single transplant center. RESULTS: Four hundred and twenty-six patients underwent transplant during this study interval; 31% of patients were sarcopenic. Two hundred eight patients underwent LFI evaluation: 25% were frail, 59% were prefrail, and 16% were robust. Sarcopenic patients had higher LFI scores indicating greater frailty (p = 0.02). Both sarcopenia and LFI-frailty were associated with significantly higher MELD-Na scores. Length of post-LT hospital stay was increased in sarcopenic (mean 14 vs. nonsarcopenic 11 days, p = 0.02) and LFI-frail patients (mean 13 vs. 10 prefrail, 8 robust, p = 0.04). As a categorical variable, neither LFI-frailty nor sarcopenia were significantly associated with reduced survival at 1-year (robust 100%, prefrail 93.5%, frail 91.1%, p = 0.31) (nonsarcopenic 94.4%, sarcopenic 91.4%, p = 0.30). However, LFI score was significantly associated with mortality at 1-year (OR 2.133, p = 0.047). CONCLUSIONS: Radiographic sarcopenia is a suitable proxy for in-person frailty assessment as both L3-PMI and LFI capture frail patients' pre-LT. However, physical assessment with frailty better predicts 1-year mortality post-LT than the measurement of muscle mass.


Asunto(s)
Fragilidad , Trasplante de Hígado , Sarcopenia , Humanos , Sarcopenia/diagnóstico por imagen , Sarcopenia/etiología , Masculino , Femenino , Trasplante de Hígado/efectos adversos , Estudios Retrospectivos , Fragilidad/complicaciones , Persona de Mediana Edad , Pronóstico , Estudios de Seguimiento , Factores de Riesgo , Enfermedad Hepática en Estado Terminal/cirugía , Enfermedad Hepática en Estado Terminal/mortalidad , Enfermedad Hepática en Estado Terminal/complicaciones , Complicaciones Posoperatorias , Anciano , Tasa de Supervivencia , Estudios Transversales
3.
Sensors (Basel) ; 24(5)2024 Feb 22.
Artículo en Inglés | MEDLINE | ID: mdl-38474942

RESUMEN

It is well known that buildings have a sizeable energy and environmental footprint. In particular, in environments like university campuses, the occupants as well as occupancy in shared spaces varies over time. Systems for cooling in such environments that are centrally controlled are typically threshold driven and do not account for occupant feedback and thus are often relying on a reactive approach (fix after identifying problems). Therefore, having a fixed thermal operating set point may not be optimal in such cases-both from an occupant comfort and well-being as well as an energy efficiency perspective. To address this issue, a study was conducted which involved development and deployment of an experimental Internet of Things (IoT) prototype system and an Android application that facilitated people engagement on a university campus located in the UAE which typically exhibits hot climatic conditions. This paper showcases data driven insights obtained from this study, and in particular, how to achieve a balance between the conflicting goals of improving occupant comfort and energy efficiency. Findings from this study underscore the need for regular reassessments and adaptation. The proposed solution is low cost and easy to deploy and has the potential to reap significant savings through a reduction in energy consumption with estimates indicating around 50-100 kWh/day of savings per building and the resulting environmental impact. These findings would appeal to stakeholders who are keen to improve energy efficiency and reduce their operating expenses and environmental footprint in such climatic conditions. Furthermore, collective action from a large number of entities could result in significant impact through this cumulative effect.

4.
BMJ Case Rep ; 17(2)2024 Feb 13.
Artículo en Inglés | MEDLINE | ID: mdl-38350698

RESUMEN

Mucoid degeneration of the anterior cruciate ligament (ACL) can be treated with arthroscopic debridement, however, instability can ensue. Here, we present a fit and active woman in her 60s with severe mucoid degeneration of the ACL who underwent conservative arthroscopic debridement and treatment with intraligamentous administration of platelet-rich plasma (PRP). After 1 month, the patient demonstrated significant improvements in range of motion and pain symptoms, with nil resultant laxity. The patient was able to return to all recreational sporting activities and professional duties. Quantitative MRI conducted 6 months postoperatively revealed improved fibre orientation and formation of new parallel fibres. Compared with the preoperative scan, the mean grey value demonstrated darker pixel intensity with a smaller standard deviation (SD), potentially indicating a more uniform and less variable formation of ligamentous tissue. Therefore, PRP did not cause harm and was associated with benefit in combination with arthroscopic debridement.


Asunto(s)
Lesiones del Ligamento Cruzado Anterior , Plasma Rico en Plaquetas , Femenino , Humanos , Ligamento Cruzado Anterior , Articulación de la Rodilla/cirugía , Desbridamiento , Artroscopía
5.
Ann Surg Oncol ; 31(2): 1049-1057, 2024 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-37906385

RESUMEN

BACKGROUND: For some cancer operations, center volume is associated with improved patient outcomes. Whether this association is true for cytoreductive surgery/heated intraperitoneal chemotherapy (CRS/HIPEC) is unclear. Given the rapidly expanding use of CRS/HIPEC, the aim of this analysis was to determine whether a volume-outcome relationship exists for this strategy. METHODS: The Vizient Clinical Database® was queried for CRS/HIPEC cases from January 2020 through December 2022. Low-, medium-, and high-volume designations were made by sorting hospitals by case volume and creating equal tertiles based on total number of cases. Analysis was performed via one-way ANOVA with post-hoc Tukey test, as indicated. RESULTS: In the 36-month study period, 5165 cases were identified across 149 hospitals. Low- (n = 113), medium- (n = 25), and high-volume (n = 11) centers performed a median of 4, 21, and 47 cases per annum, respectively. Most cases were performed for appendiceal (39.3%) followed by gynecologic neoplasms (20.4%). Groups were similar with respect to age, gender, race, comorbidities, and histology. Low-volume centers were more likely to utilize the ICU post-operatively (59.6% vs. 40.5% vs. 36.3%; p = 0.02). No differences were observed in morbidity (9.4% vs. 7.1% vs. 9.0%, p = 0.71), mortality (0.9% vs. 0.6% vs. 0.7%, p = 0.93), length of stay (9.3 vs. 9.4 vs. 10 days, p = 0.83), 30-day readmissions (5.6% vs. 5.6% vs. 5.6%, p = 1.0), or total cost among groups. CONCLUSIONS: No association was found between CRS/HIPEC hospital volume and post-operative outcomes. These data suggest that in academic medical centers with HIPEC programs, outcomes for commonly treated cancers are not associated with hospital volume.


Asunto(s)
Neoplasias del Apéndice , Hipertermia Inducida , Neoplasias Peritoneales , Humanos , Femenino , Neoplasias Peritoneales/patología , Estudios Retrospectivos , Quimioterapia Intraperitoneal Hipertérmica , Protocolos de Quimioterapia Combinada Antineoplásica/uso terapéutico , Hospitales , Procedimientos Quirúrgicos de Citorreducción/efectos adversos , Neoplasias del Apéndice/patología , Terapia Combinada , Tasa de Supervivencia
6.
Sci Rep ; 13(1): 22498, 2023 12 15.
Artículo en Inglés | MEDLINE | ID: mdl-38110426

RESUMEN

During the SARS-CoV-2 pandemic, the German healthcare system faced challenges of efficiently allocating testing resources. To address this, we developed an open-source personalized recommendation system (PRS) called "CovApp". The PRS utilized a questionnaire to estimate the risk of infection, provided personalized recommendations such as testing, self-isolation, or quarantine, and featured QR code data transmission to electronic health records. The PRS served up to 2.5 million monthly users and received 67,000 backlinks from 1800 domains. We clinically evaluated the PRS at the SARS-CoV-2 testing facility at Charité and observed a 21.7% increase in patient throughput per hour and a 22.5% increase in patients per day. Patients using the PRS were twice as likely to belong to the High Risk group eligible for testing (18.6% vs. 8.9%, p < 0.0001), indicating successful compliance with CovApp's recommendations. CovApp served as a digital bridge between the population and medical staff and significantly improved testing efficiency. As an open-source platform, CovApp can be readily customized to address emerging public health crises. Further, given the EHR interface, the app is of great utility for other applications in clinical settings.


Asunto(s)
COVID-19 , SARS-CoV-2 , Humanos , COVID-19/epidemiología , Registros Electrónicos de Salud , Prueba de COVID-19 , Atención a la Salud , Internet
8.
J Clin Med ; 11(7)2022 Mar 29.
Artículo en Inglés | MEDLINE | ID: mdl-35407498

RESUMEN

Malignant peritoneal mesothelioma is a rare malignancy arising from the serosa of the peritoneal cavity. It is diagnosed based on suspicious findings on cross sectional imaging and a tissue biopsy showing confirmatory histologic and immunohistochemical features. The disease is hallmarked by its propensity to progress mainly in the peritoneal cavity. In selected patients, surgical cytoreduction and hyperthermic intra-operative peritoneal chemotherapy has become the initial preferred treatment and is associated with provide prolonged in many patients. Systemic chemotherapy using a couplet of cisplatin or gemcitabine with pemetrexed has modest response rates and duration of response. Expression of PD-L1 has been demonstrated in peritoneal mesothelioma tumors and there has been significant interest in the use of check point blockade targeted against PD-L1 in this clinical setting. Future clinical research using a combination of check point blockade with surgical cytoreduction is a high clinical priority.

9.
J Public Health Policy ; 42(4): 550-558, 2021 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-34728814

RESUMEN

In 2013, Illinois enacted a new law (SB 957) to allow undocumented motorists to acquire Temporary Visitor Driver's Licenses (TVDLs). We explored the impact of this legislation on organ donor registration in the state. Using Freedom of Information Act requests, we obtained the Illinois TVDL and general adult driver's license applicant organ donation statistics for the last 3 years from the Illinois Secretary of State. We found that between 2017 and 2019, TVDLs directly resulted in 91,720 newly registered organ donors. This group registered as organ donors at rates significantly higher (p < 0.0001) than the general population. In the 3 years studied, only 7.3% of general driver's license registrants became new organ donor registrants, while TVDL drivers signed up at an average rate of 44.9%. TVDLs resulted in a significant increase in registered organ donors. Similar policies implemented nationwide could increase donor registrations substantially. In addition, this finding among a population largely of Latin American origin may suggest strategies for future organ donor registration efforts globally.


Asunto(s)
Conducción de Automóvil , Trasplante de Órganos , Obtención de Tejidos y Órganos , Adulto , Humanos , Concesión de Licencias , Donantes de Tejidos
10.
Radiother Oncol ; 163: 32-38, 2021 10.
Artículo en Inglés | MEDLINE | ID: mdl-34311004

RESUMEN

INTRODUCTION: The success of intensification and personalisation of the curative treatment of non-small cell lung cancer (NSCLC) is strongly associated with the precision in radiotherapy. Here, we evaluate the impact of radiotherapy protocol adherence in a prospective multicentre trial. METHODS: In the open-label, randomised, controlled PET-Plan trial, patients with inoperable NSCLC were randomized at a 1:1 ratio regarding the target volume delineation informed by 1F-FDG PET and CT plus elective nodal irradiation (arm A) or target volumes informed by PET alone (arm B) and received iso-toxically dose-escalated concurrent chemoradiation. The prospectively organised quality assurance program (RTQA) included individual case review by predefined criteria. For evaluation, protocol adherence was scored as per protocol (pP), with minor (miD), intermediate (inD) and major (maD) deviations. In order to exclude biases through patients who discontinued treatment, patients who received ≥60 Gy were additionally analysed. RESULTS: Between 05/2009-11/2016, 205 patients were randomized, 204 patients started treatment according to protocol of which 31 (15%) patients had maD. Patients with maD had an inferior overall survival (OS) (HR 2.9, 95% CI 1.8-4.4, p < 0.0001) and a higher risk of loco-regional progression (HR 5.7, 95% CI 2.7-11.1, p < 0.0001). These results were significant also in the subgroup of patients receiving ≥ 60 Gy. Patients with maD concerning normal tissue delineation and/or dose constraints had a worse OS (p = 0.006) although no higher incidence of grade ≥ 3 toxicities. CONCLUSIONS: Non-adherence to the radiotherapy protocol was associated with an inferior OS and loco-regional control. These results underline the importance of RTQA.


Asunto(s)
Carcinoma de Pulmón de Células no Pequeñas , Neoplasias Pulmonares , Carcinoma de Pulmón de Células no Pequeñas/terapia , Quimioradioterapia , Humanos , Neoplasias Pulmonares/terapia , Tomografía de Emisión de Positrones , Estudios Prospectivos
11.
Exp Neurol ; 335: 113522, 2021 01.
Artículo en Inglés | MEDLINE | ID: mdl-33152354

RESUMEN

Pediatric asphyxial cardiac arrest (ACA) often leaves children with physical, cognitive, and emotional disabilities that affect overall quality of life, yet rehabilitation is neither routinely nor systematically provided. Environmental enrichment (EE) is considered a preclinical model of neurorehabilitation and thus we sought to investigate its efficacy in our established model of pediatric ACA. Male Sprague-Dawley rat pups (post-natal day 16-18) were randomly assigned to ACA (9.5 min) or Sham injury. After resuscitation, the rats were assigned to 21 days of EE or standard (STD) housing during which time motor, cognitive, and anxiety-like (i.e., affective) outcomes were assessed. Hippocampal CA1 cells were quantified on post-operative day-22. Both ACA + STD and ACA + EE performed worse on beam-balance vs. Sham controls (p < 0.05) and did not differ from one another overall (p > 0.05); however, a single day analysis on the last day of testing revealed that the ACA + EE group performed better than the ACA + STD group (p < 0.05) and did not differ from the Sham controls (p > 0.05). Both Sham groups performed better than ACA + STD (p < 0.05) but did not differ from ACA + EE (p > 0.05) in the open field test. Spatial learning and declarative memory were improved and CA1 neuronal loss was attenuated in the ACA + EE vs. ACA + STD group (p < 0.05). Collectively, the data suggest that providing rehabilitation after pediatric ACA can reduce histopathology and improve motor and cognitive ability.


Asunto(s)
Asfixia Neonatal/psicología , Asfixia Neonatal/rehabilitación , Cognición , Ambiente , Paro Cardíaco/psicología , Paro Cardíaco/rehabilitación , Rehabilitación Neurológica/métodos , Animales , Animales Recién Nacidos , Ansiedad/etiología , Ansiedad/psicología , Asfixia Neonatal/patología , Región CA1 Hipocampal/patología , Paro Cardíaco/patología , Masculino , Memoria , Desempeño Psicomotor , Ratas , Ratas Sprague-Dawley , Recuperación de la Función , Aprendizaje Espacial
12.
Cancers (Basel) ; 12(11)2020 Nov 13.
Artículo en Inglés | MEDLINE | ID: mdl-33202825

RESUMEN

(1) Background: The optimal chemotherapy (CHT) regimen for concurrent chemoradiation (cCRT) is not well defined. In this secondary analysis of the international randomized PET-Plan trial, we evaluate the efficacy of different CHT. (2) Methods: Patients with inoperable NSCLC were randomized at a 1:1 ratio regarding the target volume definition and received isotoxically dose-escalated cCRT using cisplatin 80 mg/m2 (day 1, 22) and vinorelbin 15 mg/m2 (day 1, 8, 22, 29) (P1) or cisplatin 20 mg/m2 (day 1-5, 29-33) and vinorelbin 12.5 mg/m2 (day 1, 8, 15, 29, 36, 43) (P2) or carboplatin AUC1 (day 1-5, 29-33) and vinorelbin 12.5 mg/m2 (day 1, 8, 15, 29, 36, 43) (P3) or other CHT at the treating physician's discretion. (3) Results: Between 05/2009 and 11/2016, 205 patients were randomized and 172 included in the per-protocol analysis. Patients treated in P1 or P2 had a better overall survival (OS) compared to P3 (p = 0.015, p = 0.01, respectively). Patients treated with carboplatin had a worse OS compared to cisplatin (HR 1.78, p = 0.03), but the difference did not remain significant after adjusting for age, ECOG, cardiac function creatinine and completeness of CHT. (4) Conclusions: Carboplatin doublets show no significant difference compared to cisplatin, after adjusting for possibly relevant factors, probably due to existing selection bias.

13.
Preprint en Inglés | medRxiv | ID: ppmedrxiv-20188136

RESUMEN

Over the last months, cases of SARS-CoV-2 surged repeatedly in many countries and could often be controlled with non-pharmaceutical interventions such as social distancing. We analyzed de-identified GPS tracking data from 1.15 to 1.4 million cell phones in Germany per day between March-November 2020 to identify encounters between individuals and statistically evaluate large-scale contact behavior. Using graph sampling theory we estimated the contact index (CI), a metric for number and heterogeneity of contacts and found that the contact index, and not the total number of contacts, is an accurate predsictor for the effective reproduction number R. A high correlation between CI and R occurring more than two weeks later allows timely assessment of the social behavior well before the infections become detectable. The CI quantifies the role of superspreading and allows assigning risks to specific contact behavior. We provide a critical CI-value beyond which R is expected to rise above 1 and propose to use it to leverage the social distancing interventions for the coming months.

14.
Glycoconj J ; 37(5): 599-610, 2020 10.
Artículo en Inglés | MEDLINE | ID: mdl-32767150

RESUMEN

The classical function of human chorionic gonadotropin (hCG) is its role in supporting pregnancy. hCG is a dimer consisting of two highly glycosylated subunits, alpha (CGA) and beta (CGB). The beta-hCG protein is encoded by CGB3, CGB5, CGB7 and CGB8 genes. CGB3, 5 and 8 code for an identical protein, CGB3/5/8, whereas CGB7 differs in three amino acids from CGB3/5/8. We had observed earlier that CGB7 and CGB3/5/8 display very distinct tissue expression patterns and that the tumor suppressor and transcription factor p53 can activate expression of CGB7 but not of CGB3/5/8 genes. Here, we investigate the glycan structures and possible functional differences of the two CGB variants. To this end, we established a system to produce and isolate recombinant CGA, CGB7 and CGB3/5/8 proteins. We found that N- and O-glycosylation patterns of CGB7 and CGB3/5/8 are quite similar. Functional assays were performed by testing activation of the ERK1/2 pathway and demonstrated that CGB7 and CGB5/5/8 appear to be functionally redundant isoforms, although a slight difference in the kinetics of ERK1/2 pathway activation was observed. This is the first time that biological activity of CGB7 is shown. In summary, the results lead to the hypothesis that CGB7 and CGB3/5/8 do not hold significant functional differences but that timing and cell type of their expression is the key for understanding their divergent evolution.


Asunto(s)
Gonadotropina Coriónica Humana de Subunidad beta/genética , Gonadotropina Coriónica/genética , Isoformas de Proteínas/genética , Gonadotropina Coriónica/química , Gonadotropina Coriónica Humana de Subunidad beta/química , Gonadotropina Coriónica Humana de Subunidad beta/ultraestructura , Femenino , Regulación de la Expresión Génica/genética , Glicosilación , Humanos , Embarazo
15.
Arch Gynecol Obstet ; 299(6): 1727-1736, 2019 06.
Artículo en Inglés | MEDLINE | ID: mdl-30955059

RESUMEN

PURPOSE: Successful embryo implantation into the endometrium depends on embryonic characteristics and proper endometrial development. Reproductive medicine often focuses on embryo quality, whereas reliable diagnostic tests for endometrial receptivity are still needed. We previously found that human chorionic gonadotropin (hCG), one of the earliest proteins secreted by the embryo, was also expressed by the luteal phase endometrium around the implantation window. Here, we tested our hypothesis of endometrial hCG as an implantation marker. METHODS: Endometrial biopsies and serum samples were taken from patients undergoing routine infertility diagnostics. Correlations of immunohistochemically detected endometrial hCG expression with adequate endometrial secretory transformation, the infiltration of CD45-positive leukocytes, clinical diagnostic parameters, and endometrial thickness were analyzed. RESULTS: A highly significant correlation between the endometrial score, as a measurement for regular secretory transformation, and the intensity of hCG staining was found. The invasion of CD45-positive leukocytes increased with progressing endometrial secretory transformation and rising endometrial hCG expression. In addition, serum progesterone concentrations correlated with hCG expression by the endometrial glands. CONCLUSIONS: Our results suggest endometrial hCG as a possible diagnostic parameter characterizing the endometrial secretory transformation and, thus, possibly also its implantation capability.


Asunto(s)
Biomarcadores/metabolismo , Gonadotropina Coriónica/metabolismo , Endometrio/metabolismo , Adulto , Femenino , Humanos , Adulto Joven
16.
Pediatr Res ; 85(4): 511-517, 2019 03.
Artículo en Inglés | MEDLINE | ID: mdl-30367162

RESUMEN

BACKGROUND: Cerebral edema after cardiac arrest (CA) is associated with increased mortality and unfavorable outcome in children and adults. Aquaporin-4 mediates cerebral water movement and its absence in models of ischemia improves outcome. We investigated early and selective pharmacologic inhibition of aquaporin-4 in a clinically relevant asphyxial CA model in immature rats in a threshold CA insult that produces primarily cytotoxic edema in the absence of blood-brain barrier permeability. METHODS: Postnatal day 16-18 Sprague-Dawley rats were studied in our established 9-min asphyxial CA model. Rats were randomized to aquaporin-4 inhibitor (AER-271) vs vehicle treatment, initiated at return of spontaneous circulation. Cerebral edema (% brain water) was the primary outcome with secondary assessments of the Neurologic Deficit Score (NDS), hippocampal neuronal death, and neuroinflammation. RESULTS: Treatment with AER-271 ameliorated early cerebral edema measured at 3 h after CA vs vehicle treated rats. This treatment also attenuated early NDS. In contrast to rats treated with vehicle after CA, rats treated with AER-271 did not develop significant neuronal death or neuroinflammation as compared to sham. CONCLUSION: Early post-resuscitation aquaporin-4 inhibition blocks the development of early cerebral edema, reduces early neurologic deficit, and blunts neuronal death and neuroinflammation post-CA.


Asunto(s)
Acuaporina 4/antagonistas & inhibidores , Asfixia/complicaciones , Edema Encefálico/prevención & control , Compuestos de Flúor/uso terapéutico , Paro Cardíaco/fisiopatología , Animales , Región CA1 Hipocampal/patología , Clorofenoles , Modelos Animales de Enfermedad , Femenino , Compuestos de Flúor/farmacología , Paro Cardíaco/etiología , Humanos , Masculino , Ratas , Ratas Sprague-Dawley , Resultado del Tratamiento
17.
J Cereb Blood Flow Metab ; 39(5): 913-925, 2019 05.
Artículo en Inglés | MEDLINE | ID: mdl-29192562

RESUMEN

Decreased cerebral blood flow (CBF) after cardiac arrest (CA) contributes to secondary ischemic injury in infants and children. We previously reported cortical hypoperfusion with tissue hypoxia early in a pediatric rat model of asphyxial CA. In order to identify specific alterations as potential therapeutic targets to improve cortical hypoperfusion post-CA, we characterize the CBF alterations at the cortical microvascular level in vivo using multiphoton microscopy. We hypothesize that microvascular constriction and disturbances of capillary red blood cell (RBC) flow contribute to cortical hypoperfusion post-CA. After resuscitation from 9 min asphyxial CA, transient dilation of capillaries and venules at 5 min was followed by pial arteriolar constriction at 30 and 60 min (19.6 ± 1.3, 19.3 ± 1.2 µm at 30, 60 min vs. 22.0 ± 1.2 µm at baseline, p < 0.05). At the capillary level, microcirculatory disturbances were highly heterogeneous, with RBC stasis observed in 25.4% of capillaries at 30 min post-CA. Overall, the capillary plasma mean transit time was increased post-CA by 139.7 ± 51.5%, p < 0.05. In conclusion, pial arteriolar constriction, the no-reflow phenomenon and increased plasma transit time were observed post-CA. Our results detail the microvascular disturbances in a pediatric asphyxial CA model and provide a powerful platform for assessing specific vascular-targeted therapies.


Asunto(s)
Encéfalo/irrigación sanguínea , Circulación Cerebrovascular , Paro Cardíaco/complicaciones , Microcirculación , Fenómeno de no Reflujo/etiología , Animales , Encéfalo/fisiopatología , Paro Cardíaco/fisiopatología , Masculino , Fenómeno de no Reflujo/fisiopatología , Ratas Sprague-Dawley , Vasodilatación
18.
J Neurosci Methods ; 311: 436-441, 2019 01 01.
Artículo en Inglés | MEDLINE | ID: mdl-30292824

RESUMEN

BACKGROUND: The glymphatic system is a proposed pathway for clearance of proteins and macromolecules from brain, and disrupted glymphatic flux is implicated in neurological disease. We capitalized on colorimetric, fluorescent, and protein-binding properties of Evans blue to evaluate glymphatic flux. NEW METHOD: Twenty-five µL of 1% Evans blue-labeled albumin (EBA) in artificial cerebrospinal fluid (aCSF) was injected into the intracisternal space of anesthetized postnatal day 17 rats. Serum was collected at various time points after injection (n = 37) and EBA was measured spectrophotometrically. In separate rats (n = 3), a cranial window was placed over the parietal cortex and EBA transit was evaluated using in vivo multiphoton microscopy. Separate rats (n = 6) were processed for immunohistochemistry to examine localization of EBA. In some rats, intracranial pressure (ICP) was increased via intracisternal injection of aCSF. RESULTS: EBA was detected in serum as early as 30 min, was maximal at 4 h, and was undetectable at 72 h after intracisternal injection. Using intra-vital microscopy and immunohistochemistry EBA could be tracked from CSF to perivascular locations. Consistent with removal via glymphatic flux, increasing ICP to 40 mmHg accelerated transit of EBA from CSF to blood. COMPARISON WITH EXISTING METHODS: Transit of EBA from CSF to serum could be quantified spectrophotometrically without radioactive labeling. Glymphatic flux could also be qualitatively evaluated using EBA fluorescence. CONCLUSION: We present a novel technique for simultaneous quantitative and qualitative evaluation of glymphatic flux in rats.


Asunto(s)
Encéfalo/metabolismo , Azul de Evans , Sistema Glinfático/metabolismo , Inmunohistoquímica/métodos , Suero , Espectrofotometría/métodos , Animales , Química Encefálica , Líquido Cefalorraquídeo/química , Líquido Cefalorraquídeo/metabolismo , Sistema Glinfático/química , Ratas Sprague-Dawley
19.
ASN Neuro ; 10: 1759091418770543, 2018.
Artículo en Inglés | MEDLINE | ID: mdl-29741097

RESUMEN

Mild traumatic brain injury (mTBI) in children is a common and serious public health problem. Traditional neuroimaging findings in children who sustain mTBI are often normal, putting them at risk for repeated mTBI (rmTBI). There is a need for more sensitive imaging techniques capable of detecting subtle neurophysiological alterations after injury. We examined neurochemical and white matter changes using diffusion tensor imaging of the whole brain and proton magnetic resonance spectroscopy of the hippocampi at 7 Tesla in 18-day-old male rats at 7 days after mTBI and rmTBI. Traumatic axonal injury was assessed by beta-amyloid precursor protein accumulation using immunohistochemistry. A significant decrease in fractional anisotropy and increase in axial and radial diffusivity were observed in several brain regions, especially in white matter regions, after a single mTBI versus sham and more prominently after rmTBI. In addition, we observed accumulation of beta-amyloid precursor protein in the external capsule after mTBI and rmTBI. mTBI and rmTBI reduced the N-acetylaspartate/creatine ratio (NAA/Cr) and increased the myoinositol/creatine ratio (Ins/Cr) versus sham. rmTBI exacerbated the reduction in NAA/Cr versus mTBI. The choline/creatine (Cho/Cr) and (lipid/Macro Molecule 1)/creatine (Lip/Cr) ratios were also decreased after rmTBI versus sham. Diffusion tensor imaging findings along with the decrease in Cho and Lip after rmTBI may reflect damage to axonal membrane. NAA and Ins are altered at 7 days after mTBI and rmTBI likely reflecting neuro-axonal damage and glial response, respectively. These findings may be relevant to understanding the extent of disability following mTBI and rmTBI in the immature brain and may identify possible therapeutic targets.


Asunto(s)
Ácido Aspártico/análogos & derivados , Conmoción Encefálica/diagnóstico por imagen , Conmoción Encefálica/metabolismo , Encéfalo/diagnóstico por imagen , Encéfalo/metabolismo , Inositol/metabolismo , Precursor de Proteína beta-Amiloide/metabolismo , Animales , Animales Recién Nacidos , Anisotropía , Ácido Aspártico/metabolismo , Creatina/metabolismo , Modelos Animales de Enfermedad , Lateralidad Funcional , Procesamiento de Imagen Asistido por Computador , Imagen por Resonancia Magnética , Masculino , Espectroscopía de Protones por Resonancia Magnética , Ratas , Ratas Sprague-Dawley
20.
Radiother Oncol ; 128(2): 229-235, 2018 08.
Artículo en Inglés | MEDLINE | ID: mdl-29699833

RESUMEN

PURPOSE OR OBJECTIVE: A homogeneity index (HI) measures the uniformity of a dose distribution within a given target volume. Traditional HIs only use a limited number of dose-volume histogram data-points for calculation. A voxel-based homogeneity index (VHI) is proposed which utilizes the entire information of the three-dimensional dose distribution. We compared the VHI with existing HIs and analyzed if VHI results were associated with treatment outcomes in patients who underwent therapeutic WBRT. MATERIAL AND METHODS: The VHI analyzes deviations from the prescribed dose in each voxel of the target volume. We retrospectively analyzed WBRT treatment plans. Overall survival (OS), CNS progression-free-survival (CNS PFS) and hazard rates were compared for tertile-split levels of the VHI using the Kaplan-Meier methods and multivariable Cox-regression analysis. RESULTS: WBRT treatment plans (n = 770) were used for HIs comparison. OS and CNS PFS were assessed for 430 patients. The VHI showed a higher sensitivity for dose inhomogeneities. Lower OS and CNS PFS were observed for higher levels of VHIUnderdosage, particularly in patients with good performance status (KPS >70%) (OS: Log-rank P = .007, HR = 1.37 95%CI [1.09, 1.72]). CONCLUSION: Higher sensitivity and feasibility to assess treatment plan quality using the VHI were demonstrated. First clinical implications were found in terms of compromised OS/CNS PFS for WBRT with radiation underdosage.


Asunto(s)
Neoplasias Encefálicas/radioterapia , Irradiación Craneana/métodos , Adulto , Anciano , Anciano de 80 o más Años , Encéfalo/efectos de la radiación , Neoplasias Encefálicas/mortalidad , Neoplasias Encefálicas/secundario , Irradiación Craneana/mortalidad , Métodos Epidemiológicos , Femenino , Humanos , Masculino , Persona de Mediana Edad , Dosificación Radioterapéutica , Resultado del Tratamiento
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