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1.
Dev Cell ; 2024 Jun 05.
Artigo em Inglês | MEDLINE | ID: mdl-38870943

RESUMO

In crowded microenvironments, migrating cells must find or make a path. Amoeboid cells are thought to find a path by deforming their bodies to squeeze through tight spaces. Yet, some amoeboid cells seem to maintain a near-spherical morphology as they move. To examine how they do so, we visualized amoeboid human melanoma cells in dense environments and found that they carve tunnels via bleb-driven degradation of extracellular matrix components without the need for proteolytic degradation. Interactions between adhesions and collagen at the cell front induce a signaling cascade that promotes bleb enlargement via branched actin polymerization. Large blebs abrade collagen, creating feedback between extracellular matrix structure, cell morphology, and polarization that enables both path generation and persistent movement.

2.
Pediatr Crit Care Med ; 24(9): e409-e416, 2023 09 01.
Artigo em Inglês | MEDLINE | ID: mdl-37125796

RESUMO

OBJECTIVES: Hyperferritinemia in the critical phase of dengue infections may correlate with severe dengue ( sd ) disease, and our primary objective was to examine the association between ferritin level on day 1 of PICU admission and 2009 World Health Organization (WHO) criteria for sd . Our secondary objective was outcome in relation to care. It is unclear whether immunomodulatory therapy during the critical phase may restore immune homeostasis and mitigate disease severity. DESIGN, SETTING, AND PATIENTS: Retrospective cohort study of children with dengue 1 month to 16 years old with admission ferritin greater than or equal to 500 ng/mL requiring PICU admission. Demographics, clinical, and laboratory parameters, presence of the 2009 WHO sd criteria and outcomes were analyzed. Immunomodulatory therapy was used when there was persistent hyperinflammation beyond the critical phase of plasma leakage. INTERVENTIONS: None. MEASUREMENTS AND MAIN RESULTS: Fifty-five patients were admitted in the critical phase of dengue with median (interquartile range) ferritin levels of 8,105 ng/mL (2,350-15,765 ng/mL). Patients with at least one WHO sd category had higher ferritin levels compared to those without any sd criteria, with the highest levels in eight patients with all three sd categories. In our cohort of 55, 52 patients (94%) recovered with standard supportive therapy. Recovery was associated with decreased ferritin levels that occurred in parallel with improved circulation and platelet counts; this included 22 of 24 patients with admission ferritin levels greater than or equal to 10,000 ng/mL and two with ferritin greater than 1,00,000 ng/mL. Immunomodulation was used in three patients with unremitting fever, persistent hyperferritinemia, and progressive multiple organ dysfunction beyond the critical phase, of whom two died. CONCLUSIONS: Hyperferritinemia in the critical phase of sd is associated with the number of 2009 WHO sd criteria present. Our data also indicate that many patients with sd recover well with supportive care.


Assuntos
Hiperferritinemia , Dengue Grave , Criança , Humanos , Estudos Retrospectivos , Ferritinas , Contagem de Plaquetas
3.
Hand (N Y) ; : 15589447231168909, 2023 May 09.
Artigo em Inglês | MEDLINE | ID: mdl-37157827

RESUMO

BACKGROUND: The opioid epidemic is a health crisis in the United States. Physicians contribute to this problem by overprescribing opioids. Ambulatory hand surgery (AHS) is common in the United States and associated with overprescribing of opioids. Education and guidance regarding the effectiveness of nonopioid compared with opioid interventions for pain management following ambulatory hand procedures are lacking. We assessed the current literature to suggest evidence-based protocols for postoperative analgesia. METHODS: A systematic review was performed using PubMed, Web of Science, and Cochrane Library. Studies comparing nonopioid with opioid treatments for pain management following AHS were identified. Studies investigating opioid-sparing strategies after AHS were also identified. Evidence was examined to determine efficacy of nonopioid interventions and to provide recommendations for optimal nonopioid protocols and opioid-sparing strategies. RESULTS: A total of 510 studies were identified in the search with 18 meeting inclusion criteria. High-level evidence demonstrated efficacy of nonopioid interventions for pain management following AHS (levels I and II evidence). Results provided evidence-based guidelines for recommendations of nonopioid treatment protocols and opioid-sparing strategies (levels I and II evidence). CONCLUSIONS: Our review demonstrated nonopioid interventions are adequate in multiple aspects of pain management compared with opioid treatments. Recommendations were established for two nonopioid treatment protocols, and for an opioid-sparing intervention (levels I and II evidence). The evidence provided in this review should be strongly considered for pain management guidance following AHS and provides a means to decrease opioid overprescribing in the United States.

4.
Asian J Transfus Sci ; 17(1): 136-138, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37188034

RESUMO

Rare blood group detection is important as the incidence of these blood groups is very low. These rare blood groups need a transfusion of blood from the same group of people; sometimes, it is not available in blood banks. It is important to detect them in the field of transfusion medicine so that the right transfusion at the right time and for the right patient is ensured. We had one patient who was identified as blood group O in a private laboratory and the patient came to our hospital for anemia during the second trimester of pregnancy whose forward grouping showed no agglutination in the anti-a and anti-b and also no agglutination in the anti-H so we thought it to be Bombay blood group. We performed the reverse grouping and we found agglutination with pooled A cells and pooled B cells but no agglutination in the pooled O cells. We found forward and reverse grouping were discordant so we concluded that the patient had Bombay variant blood group, the secretor status of the patient was done in saliva using hemagglutination inhibition test and we found that the patient had secretion of H substance in the saliva. Rh typing: it was found that the patient had positive in Rh typing. Family members were screened and they all were O positive. Forward and reverse grouping along with the secretor status detection helped to detect the case. This case report highlights the importance of blood grouping forward and reverse and also using Anti-H reagent for blood grouping and also the use of secretor status in the detection of proper blood grouping of the patient.

5.
Nature ; 615(7952): 517-525, 2023 03.
Artigo em Inglês | MEDLINE | ID: mdl-36859545

RESUMO

Most human cells require anchorage for survival. Cell-substrate adhesion activates diverse signalling pathways, without which cells undergo anoikis-a form of programmed cell death1. Acquisition of anoikis resistance is a pivotal step in cancer disease progression, as metastasizing cells often lose firm attachment to surrounding tissue2,3. In these poorly attached states, cells adopt rounded morphologies and form small hemispherical plasma membrane protrusions called blebs4-11. Bleb function has been thoroughly investigated in the context of amoeboid migration, but it has been examined far less in other scenarios12. Here we show by three-dimensional imaging and manipulation of cell morphological states that blebbing triggers the formation of plasma membrane-proximal signalling hubs that confer anoikis resistance. Specifically, in melanoma cells, blebbing generates plasma membrane contours that recruit curvature-sensing septin proteins as scaffolds for constitutively active mutant NRAS and effectors. These signalling hubs activate ERK and PI3K-well-established promoters of pro-survival pathways. Inhibition of blebs or septins has little effect on the survival of well-adhered cells, but in detached cells it causes NRAS mislocalization, reduced MAPK and PI3K activity, and ultimately, death. This unveils a morphological requirement for mutant NRAS to operate as an effective oncoprotein. Furthermore, whereas some BRAF-mutated melanoma cells do not rely on this survival pathway in a basal state, inhibition of BRAF and MEK strongly sensitizes them to both bleb and septin inhibition. Moreover, fibroblasts engineered to sustain blebbing acquire the same anoikis resistance as cancer cells even without harbouring oncogenic mutations. Thus, blebs are potent signalling organelles capable of integrating myriad cellular information flows into concerted cellular responses, in this case granting robust anoikis resistance.


Assuntos
Anoikis , Carcinogênese , Extensões da Superfície Celular , Sobrevivência Celular , Melanoma , Transdução de Sinais , Humanos , Melanoma/genética , Melanoma/metabolismo , Melanoma/patologia , Fosfatidilinositol 3-Quinases/metabolismo , Septinas/metabolismo , Extensões da Superfície Celular/química , Extensões da Superfície Celular/metabolismo , Carcinogênese/genética , Adesão Celular , MAP Quinases Reguladas por Sinal Extracelular , Fibroblastos , Mutação , Forma Celular , Imageamento Tridimensional , Quinases de Proteína Quinase Ativadas por Mitógeno
6.
Br J Surg ; 109(4): 372-380, 2022 03 15.
Artigo em Inglês | MEDLINE | ID: mdl-35170730

RESUMO

BACKGROUND: Retransplantation candidates are disadvantaged owing to lack of good-quality liver grafts. Strategies that can facilitate transplantation of suboptimal grafts into retransplant candidates require investigation. The aim was to determine whether late liver retransplantation can be performed safely with suboptimal grafts, following normothermic machine perfusion. METHODS: A prospectively enrolled group of patients who required liver retransplantation received a suboptimal graft preserved via normothermic machine perfusion. This group was compared with both historical and contemporaneous cohorts of patient who received grafts preserved by cold storage. The primary outcome was 6-month graft and patient survival. RESULTS: The normothermic machine perfusion group comprised 26 patients. The historical (cold storage 1) and contemporaneous (cold storage 2) groups comprised 31 and 25 patients respectively. The 6-month graft survival rate did not differ between groups (cold storage 1, 27 of 31, cold storage 2, 22 of 25; normothermic machine perfusion, 22 of 26; P = 0.934). This was despite the normothermic machine perfusion group having significantly more steatotic grafts (8 of 31, 7 of 25, and 14 of 26 respectively; P = 0.006) and grafts previously declined by at least one other transplant centre (5 of 31, 9 of 25, and 21 of 26; P < 0.001). CONCLUSION: In liver retransplantation, normothermic machine perfusion can safely expand graft options without compromising short-term outcomes.


Liver transplantation is a life-saving procedure for many different diseases. In the UK, one in 10 patients awaiting transplant have had a previous liver transplant. These retransplant operations are complex, and the general belief is that a good-quality donor liver graft is required for best outcomes. However, there is a significant shortage of good-quality organs for liver transplantation, so many patients awaiting retransplantation spend longer on the waiting list. This study investigated whether a new technology, called normothermic machine perfusion, could be used to preserve lower-quality donor livers and have successful outcomes for patients undergoing retransplantation. Traditionally, good-quality livers are preserved in an ice box and the study compared the outcomes of these two different approaches. The aim was to prove that normothermic machine perfusion improves access to transplantation for this group of patients, without compromising outcomes. A group of patients who underwent retransplantation and received a lesser-quality liver preserved with normothermic machine perfusion was compared with two groups of patients who had received a transplant with traditional ice-box preservation. The complications, graft, and patient survival of the former group was compared with those in the latter two groups who underwent liver retransplantation with better-quality liver grafts. The rate of survival and adverse surgical outcomes were comparable between the groups of patients who received a liver preserved via traditional ice-box preservation, and those who received a lesser-quality liver preserved via normothermic machine perfusion. Normothermic machine perfusion can potentially expand the number of suitable donor livers available for retransplant candidates.


Assuntos
Transplante de Fígado , Sobrevivência de Enxerto , Humanos , Fígado , Preservação de Órgãos , Perfusão
7.
J Reconstr Microsurg ; 38(1): 56-63, 2022 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-34010964

RESUMO

BACKGROUND: Replantation is the ideal treatment in traumatic scalp defects to provide immediate coverage with restoration of hair-bearing skin. However, data are limited to case reports and small case series. Comprehensive analysis of techniques and outcomes is not available. Our aim was to systematically analyze the available literature to better understand management and postoperative outcomes of patients undergoing scalp replantation. METHODS: A systematic review of the PubMed, Cochrane, and EBSCO databases was performed in October 2019. Search terms included "replantation," "replant," "revascularized," "revascularization," "avulsion," and "scalp." Only papers reporting microvascular replantation of completely avulsed scalps, including case reports, were included. Review articles, non-English language articles, articles discussing nonreplant coverage, incomplete scalp avulsions, and articles discussing delayed scalp replantation were excluded. Data extracted included demographics, percent of scalp affected, mechanism, operative technique, and postoperative outcomes. Statistical analysis was performed using Mann-Whitney U tests, Kruskal-Wallis, and chi-squared tests. RESULTS: From a total of 704 initial results, 61 studies were included for analysis comprising 149 scalps. Complete survival was achieved in 54.7%, partial survival in 38.9%, and failure in 6.7%. Total ischemia time greater than 12 hours was associated with complete replant failure. Arterial anastomoses appeared to protect against complete loss. The number of venous repairs, proportion of venous-to-arterial repairs, use of vein grafts, thromboprophylaxis, or intraoperative complications did not affect outcomes. Patients required significant volumes of blood products, which was associated with partial success. Salvage rate after unplanned return to the operating room was 60.0%. Normal hair growth was achieved in all surviving native scalp tissue. CONCLUSION: Scalp replantations, while technically challenging, are the ideal treatment for scalp avulsions. Fortunately, these have high rates of success. And as a focal point of a patient's appearance, this is invaluable in restoration of a sense of normalcy.


Assuntos
Couro Cabeludo , Tromboembolia Venosa , Anticoagulantes , Humanos , Microcirurgia , Reimplante , Couro Cabeludo/cirurgia
8.
Nat Methods ; 18(7): 829-834, 2021 07.
Artigo em Inglês | MEDLINE | ID: mdl-34183831

RESUMO

We introduce a cost-effective and easily implementable scan unit that converts any camera-based microscope with optical sectioning capability into a multi-angle projection imaging system. Projection imaging reduces data overhead and accelerates imaging by a factor of >100, while also allowing users to readily view biological phenomena of interest from multiple perspectives on the fly. By rapidly interrogating the sample from just two perspectives, our method also enables real-time stereoscopic imaging and three-dimensional particle localization. We demonstrate projection imaging with spinning disk confocal, lattice light-sheet, multidirectional illumination light-sheet and oblique plane microscopes on specimens that range from organelles in single cells to the vasculature of a zebrafish embryo. Furthermore, we leverage our projection method to rapidly image cancer cell morphodynamics and calcium signaling in cultured neurons at rates up to 119 Hz as well as to simultaneously image orthogonal views of a beating embryonic zebrafish heart.


Assuntos
Processamento de Imagem Assistida por Computador/métodos , Microscopia Confocal/instrumentação , Microscopia Confocal/métodos , Animais , Colo/citologia , Embrião não Mamífero/citologia , Feminino , Coração/diagnóstico por imagem , Coração/embriologia , Humanos , Imageamento Tridimensional , Masculino , Camundongos , Camundongos Transgênicos , Neurônios/citologia , Ratos Sprague-Dawley , Esferoides Celulares/patologia , Peixe-Zebra/embriologia
9.
J Sex Med ; 18(7): 1280-1291, 2021 07.
Artigo em Inglês | MEDLINE | ID: mdl-34140253

RESUMO

BACKGROUND: Feminizing and masculinizing hormone treatments are established components of management in transgender patients. Exogenous hormones have been associated with hemostatic effects, which are well-studied in cis-gender individuals on hormone replacement therapy (HRT). Unfortunately, comprehensive understanding of their effects on venous thromboembolism (VTE) risk in the transgender population is lacking. AIM: This manuscript aims to identify the risk of VTE among transgender individuals undergoing cross-sex hormone therapy. METHODS: A Systematic review of the literature was performed in March 2020 for studies reporting VTE rates in transgender patients undergoing hormone treatment and rates in cis-gender patients on HRT. Data regarding demographics, hormone therapy, and VTE incidence were collected and pooled for analysis. OUTCOME: The primary outcome of interest was the development of a VTE event in association with concurrent hormone administration. RESULTS: Overall, 22 studies were included with 11 reporting VTE rates among transgender patients, 6 in cis-female patients, and 5 in cis-male patients. Data from 9,180 transgender patients (6,068 assigned male at birth [AMAB] and 3,112 assigned female at birth [AFAB]) undergoing hormone treatment and 103,713 cis-gender patients (18,748 female and 84,965 male) undergoing HRT were pooled. The incidence of VTE was higher in AMAB patients compared to AFAB patients (42.8 vs 10.8 VTE per 10,000 patient years; P = .02). The rate of VTE incidences in AMAB patients appears similar or higher than the rate demonstrated in cis-females on HRT. VTE incidence in AFAB patients, however, is similar to the published rates in cis-males on HRT. CLINICAL IMPLICATIONS: AMAB patients on hormone therapy have higher VTE rates than AFAB patients. AMAB and AFAB patients may have similar VTE incidence to cis-female and cis-male patients on hormone replacement therapy, respectively. STRENGTHS & LIMITATIONS: This is the first study to aggregate and quantify the development of VTE events in association with hormone therapy in transgender patients. It places these values in the context of rates published in more widely studied populations. It is limited by its retrospective data and heterogenic data. CONCLUSION: Surgical planning regarding perioperative and postoperative VTE prophylaxis or cessation of hormone therapy should take into account each patient's Caprini risk assessment and the nature of each intervention. Kotamarti VS, Greige N, Heiman AJ, et al. Risk for Venous Thromboembolism in Transgender Patients Undergoing Cross-Sex Hormone Treatment: A Systematic Review. J Sex Med 2021;18:1280-1291.


Assuntos
Pessoas Transgênero , Transexualidade , Tromboembolia Venosa , Feminino , Hormônios Esteroides Gonadais , Humanos , Recém-Nascido , Masculino , Estudos Retrospectivos , Fatores de Risco , Tromboembolia Venosa/induzido quimicamente , Tromboembolia Venosa/epidemiologia
10.
J Reconstr Microsurg ; 37(4): 336-345, 2021 May.
Artigo em Inglês | MEDLINE | ID: mdl-32957153

RESUMO

BACKGROUND: Postmastectomy radiation therapy (PMRT) decreases loco-regional recurrence and improves survival in patients with locally advanced breast cancer. Autologous free flap reconstruction, while more durable in the setting of radiation than alloplastic reconstruction, is still susceptible to radiation-induced fibrosis, contracture, fat necrosis, volume loss, and distortion of breast shape. Options for reconstruction timing (immediate vs. delayed) have been discussed to mitigate these effects, but a clear optimum is not known. METHODS: A systematic review of the literature was conducted according to PRISMA (Preferred Reporting Items for Systematic Reviews and Meta-Analyses) guidelines using search terms "breast reconstruction AND (radiation OR irradiation OR radiotherapy)" were used. Inclusion criteria consisted of studies reporting complications for free flap breast reconstruction in the setting of PMRT. Patients who underwent PMRT were pooled into two groups: those who underwent immediate free flap reconstruction prior to PMRT and those who underwent delayed reconstruction after PMRT. RESULTS: Out of the 23 studies, 12 focused on immediate reconstruction, seven focused on delayed reconstruction, and four studies included both groups. Overall, 729 patients underwent immediate reconstruction, while 868 underwent delayed reconstruction. Complete and partial flap loss rates were significantly higher in patients undergoing delayed reconstruction, while infection and wound-healing complication rates were higher in those undergoing immediate reconstructions. Rates of unplanned reoperations, vascular complications, hematoma/seroma, and fat necrosis did not differ significantly between the two groups. However, rates of planned revision surgeries were higher in the delayed reconstruction group. CONCLUSION: Immediate free flap breast reconstruction is associated with superior flap survival compared with delayed reconstruction. Rates of complications are largely comparable, and rates of revision surgeries are equivalent. The differences in long-term aesthetic outcomes are not, however, clearly assessed by the available literature. Even in the face of PMRT, immediate free flap breast reconstruction is an effective approach.


Assuntos
Neoplasias da Mama , Mamoplastia , Neoplasias da Mama/radioterapia , Neoplasias da Mama/cirurgia , Seguimentos , Humanos , Mastectomia , Recidiva Local de Neoplasia , Complicações Pós-Operatórias , Radioterapia Adjuvante , Estudos Retrospectivos , Resultado do Tratamento
11.
J Surg Res ; 256: 381-389, 2020 12.
Artigo em Inglês | MEDLINE | ID: mdl-32745748

RESUMO

BACKGROUND: Computed tomography of the head (CTH) and maxillofacial bones (CTMF) can be performed concurrently, but CTMF is frequently ordered separately, after facial fractures identified on CTH scans. This study aims to evaluate whether obtaining additional CTMF after CTH changes operative management of patients with facial trauma. MATERIALS AND METHODS: A retrospective chart review was performed of all patients with facial trauma who presented to our level 1 trauma center between January 2009 and May 2019. CTH and CTMF were reviewed for each patient. Fracture numbers and patterns were compared to determine if CTMF provided additional information that necessitated change in management, based on predetermined criteria. RESULTS: A total of 1215 patients were assessed for facial trauma. Of them, 899 patients underwent both CTH and CTMF scans. CTH identified 22.7% less fractures than CTMF (P < 0.001); specifically, more orbital, nasal, naso-orbito-ethmoid, zygoma, midface, and mandible fractures (P < 0.001). Of all patients 9.2% (n = 83) of patients with nonoperative fractures on CTH were reclassified as operative on CTMF; 0.6% (n = 5) with operative patterns on CTH were reclassified as nonoperative on CTMF, and 18.1% (n = 163) experienced a changed in their operative plan though operative fractures were seen on both imaging modalities. Additional findings seen on CTMF delegated change in the operative plan in 27.9% (n = 251) of cases. CONCLUSIONS: CTMF scans are necessary to determine operative intervention. As CTH and CTMF are constructed from the data, physicians should consider ordering both scans simultaneously for all patients with facial trauma to limit radiation exposure, control costs, and avoid delays in care.


Assuntos
Ossos Faciais/diagnóstico por imagem , Cabeça/diagnóstico por imagem , Fraturas Mandibulares/diagnóstico , Fraturas Cranianas/diagnóstico , Tomografia Computadorizada por Raios X/estatística & dados numéricos , Adulto , Ossos Faciais/lesões , Ossos Faciais/cirurgia , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Cuidados Pré-Operatórios/estatística & dados numéricos , Estudos Retrospectivos , Fraturas Cranianas/cirurgia , Fatores de Tempo , Tempo para o Tratamento , Adulto Jovem
12.
J Reconstr Microsurg ; 36(3): 204-212, 2020 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-31766062

RESUMO

BACKGROUND: Despite improvements in microsurgical techniques, hypercoagulable patients remain a reconstructive challenge. Thrombophilias are a relatively common problem with potentially catastrophic results including free flap loss. The aim of this study was to assess the available literature on free tissue transfer in patients with known hypercoagulability to develop recommendations for management. METHODS: A systematic review of the PubMed, EBSCO, and Cochrane databases was performed in June 2018. Inclusion criteria were assessment of outcomes of free tissue transfer in patients with established hypercoagulability. Exclusion criteria were review articles, case reports, and studies lacking detailed discussion of anticoagulation regimens and surgical outcomes. Data collected included the number of hypercoagulable patients, anticoagulation regimens, thrombotic complications, flap success, and bleeding complications. Statistical analysis was performed using independent samples t-tests. RESULTS: Of 147 total results, four articles were included for analysis. One relevant article published after search completion was included. In total, 185 free tissue transfers were performed in 155 thrombophilic patients. Anticoagulation regimens varied widely but often included intraoperative continuous heparin, with or without additional bolus, followed by postoperative and outpatient anticoagulation. Hypercoagulable patients often developed late postoperative thromboses. Of the intraoperative thromboses, 36.4% were successfully salvaged. No flaps with postoperative thrombosis were salvaged. Preemptive therapeutic anticoagulation improved outcomes but increased the bleeding risk. CONCLUSION: Free tissue transfer may be successful in hypercoagulable patients. High-risk patients identified preoperatively should receive therapeutic anticoagulation initiated intraoperatively unless contraindicated. Salvage after postoperative thrombosis is poor. Ultimately, the benefits of free tissue transfer must be considered with the potential morbidity of bleeding complications on a case-by-case basis when developing a reconstructive plan. Initiating anticoagulation based on the presence of intraoperative risk factors may prevent unnecessary intervention.


Assuntos
Anticoagulantes/uso terapêutico , Retalhos de Tecido Biológico/irrigação sanguínea , Trombofilia/complicações , Trombofilia/prevenção & controle , Sobrevivência de Enxerto , Humanos , Complicações Pós-Operatórias/prevenção & controle , Procedimentos de Cirurgia Plástica
15.
J Burn Care Res ; 40(5): 541-549, 2019 08 14.
Artigo em Inglês | MEDLINE | ID: mdl-31188429

RESUMO

Frostbite is a cold injury that results in soft tissue loss and can lead to amputation. Vascular thrombosis following injury causes ischemic tissue damage. Despite understanding the pathology, its treatment has remained largely unchanged for over 30 years. Threatened extremities may be salvaged with thrombolytics to restore perfusion. The authors performed a systematic review to determine whether thrombolytic therapy is effective and to identify patients who may benefit from this treatment. The Pubmed, EBSCO, and Google Scholar databases were queried using the key words "thrombolytics," "frostbite," "fibrinolytics," and "tPA." Studies written after 1990 in English met inclusion criteria. Exclusion criteria were failure to delineate anatomic parts injured, failure to report number of limbs salvaged, animal studies, and non-English language publications. Thrombolytic therapy was defined as administration of tPA, alteplase, urokinase, or streptokinase. Forty-two studies were identified and 17 included. Included were 1 randomized trial, 10 retrospective studies, 2 case series, and 4 case reports. One thousand eight hundred and forty-four limbs and digits in 325 patients were studied and 216 patients treated with thrombolytics and 346 amputations performed. The most common means of thrombolysis was intra-arterial tPA. The most common duration of therapy was 48 hours. Limb salvage rates ranged from 0% to 100% with a weighted average of 78.7%. Thrombolytics are a safe and effective treatment of severe frostbite. They represent the first significant advancement in frostbite treatment by preventing otherwise inevitable amputations warranting both greater utilization and further research to clarify the ideal thrombolytic protocol.


Assuntos
Extremidades/lesões , Congelamento das Extremidades/terapia , Salvamento de Membro , Terapia Trombolítica , Humanos
16.
Dev Cell ; 49(3): 444-460.e9, 2019 05 06.
Artigo em Inglês | MEDLINE | ID: mdl-31063759

RESUMO

Actin assembly supplies the structural framework for cell morphology and migration. Beyond structure, this actin framework can also be engaged to drive biochemical signaling programs. Here, we describe how the hyperactivation of Rac1 via the P29S mutation (Rac1P29S) in melanoma hijacks branched actin network assembly to coordinate proliferative cues that facilitate metastasis and drug resistance. Upon growth challenge, Rac1P29S-harboring melanoma cells massively upregulate lamellipodia formation by dendritic actin polymerization. These extended lamellipodia form a signaling microdomain that sequesters and phospho-inactivates the tumor suppressor NF2/Merlin, driving Rac1P29S cell proliferation in growth suppressive conditions. These biochemically active lamellipodia require cell-substrate attachment but not focal adhesion assembly and drive proliferation independently of the ERK/MAPK pathway. These data suggest a critical link between cell morphology and cell signaling and reconcile the dichotomy of Rac1's regulation of both proliferation and actin assembly by revealing a mutual signaling axis wherein actin assembly drives proliferation in melanoma.


Assuntos
Células Dendríticas/metabolismo , Melanoma/metabolismo , Pseudópodes/metabolismo , Proteínas rac1 de Ligação ao GTP/metabolismo , Actinas/metabolismo , Animais , Linhagem Celular Tumoral , Movimento Celular/fisiologia , Proliferação de Células/fisiologia , Dendritos/metabolismo , Dendritos/patologia , Feminino , Xenoenxertos , Humanos , Sistema de Sinalização das MAP Quinases , Melanoma/patologia , Camundongos , Camundongos Endogâmicos NOD , Camundongos SCID , Mutação , Metástase Neoplásica , Pseudópodes/patologia , Proteínas rac1 de Ligação ao GTP/genética
17.
BMC Cancer ; 19(1): 502, 2019 May 28.
Artigo em Inglês | MEDLINE | ID: mdl-31138163

RESUMO

BACKGROUND: Every biological experiment requires a choice of throughput balanced against physiological relevance. Most primary drug screens neglect critical parameters such as microenvironmental conditions, cell-cell heterogeneity, and specific readouts of cell fate for the sake of throughput. METHODS: Here we describe a methodology to quantify proliferation and viability of single cells in 3D culture conditions by leveraging automated microscopy and image analysis to facilitate reliable and high-throughput measurements. We detail experimental conditions that can be adjusted to increase either throughput or robustness of the assay, and we provide a stand alone image analysis program for users who wish to implement this 3D drug screening assay in high throughput. RESULTS: We demonstrate this approach by evaluating a combination of RAF and MEK inhibitors on melanoma cells, showing that cells cultured in 3D collagen-based matrices are more sensitive than cells grown in 2D culture, and that cell proliferation is much more sensitive than cell viability. We also find that cells grown in 3D cultured spheroids exhibit equivalent sensitivity to single cells grown in 3D collagen, suggesting that for the case of melanoma, a 3D single cell model may be equally effective for drug identification as 3D spheroids models. The single cell resolution of this approach enables stratification of heterogeneous populations of cells into differentially responsive subtypes upon drug treatment, which we demonstrate by determining the effect of RAK/MEK inhibition on melanoma cells co-cultured with fibroblasts. Furthermore, we show that spheroids grown from single cells exhibit dramatic heterogeneity to drug response, suggesting that heritable drug resistance can arise stochastically in single cells but be retained by subsequent generations. CONCLUSION: In summary, image-based analysis renders cell fate detection robust, sensitive, and high-throughput, enabling cell fate evaluation of single cells in more complex microenvironmental conditions.


Assuntos
Fibroblastos/citologia , Processamento de Imagem Assistida por Computador/métodos , Melanoma/metabolismo , Inibidores de Proteínas Quinases/farmacologia , Esferoides Celulares/citologia , Linhagem Celular Tumoral , Proliferação de Células/efeitos dos fármacos , Sobrevivência Celular/efeitos dos fármacos , Técnicas de Cocultura , Resistencia a Medicamentos Antineoplásicos , Ensaios de Seleção de Medicamentos Antitumorais , Fibroblastos/metabolismo , Ensaios de Triagem em Larga Escala , Humanos , Melanoma/tratamento farmacológico , Quinases de Proteína Quinase Ativadas por Mitógeno/antagonistas & inibidores , Análise de Célula Única , Esferoides Celulares/efeitos dos fármacos , Esferoides Celulares/metabolismo , Microambiente Tumoral , Quinases raf/antagonistas & inibidores
18.
Methods Mol Biol ; 1842: 203-206, 2018.
Artigo em Inglês | MEDLINE | ID: mdl-30196411

RESUMO

Mesenchymal stem cells (MSCs) are a population of multipotent cells that can be isolated from various adult and fetal tissues, including adipose tissue. These cells contain enormous clinical and basic research appeal due to their plasticity to differentiate into cells of all germ layers in vitro, cross allogeneic barriers in vivo, and suppress inflammation. Methods to isolate adipose-derived MSCs (ADSCs) primarily rely on enzymatic digestion of the adipose tissue using harsh enzymes such as collagenase. However, these harsh enzymes are expensive and can have detrimental effects on the ADSCs, including risks of using xenograft components in clinical application. This chapter focuses on methods of isolating ADSCs from adipose tissue without enzymatic digestion.


Assuntos
Tecido Adiposo/citologia , Separação Celular , Células-Tronco Mesenquimais/citologia , Células-Tronco Mesenquimais/metabolismo , Biomarcadores , Separação Celular/métodos , Humanos , Imuno-Histoquímica
19.
Eplasty ; 17: e25, 2017.
Artigo em Inglês | MEDLINE | ID: mdl-28890747

RESUMO

Objective: Despite improved recognition of risk factors, plastic surgeons commonly encounter seromas postoperatively and must decide upon management. Current recommendations for minimally invasive, chemical management originate from the literature on management of pneumothorax and pleural effusions. A handful of published reports have suggested the efficacy of sclerotherapy in seroma management. The aim of this study was to assess the literature on the use of sclerosants to treat subcutaneous fluid collections. Methods: A systematic review of the literature was performed on the PubMed, MEDLINE, and Cochrane databases for primary research articles on sclerotherapy for seroma treatment between January 1975 and January 2017. Exclusion criteria were surgical treatment, sclerotherapy for seroma prevention, hematoma, or absence of detailed documentation. Data related to seroma location, sclerosant, and resolutions were extracted. Results: The literature search yielded 7 relevant articles of level IV evidence and 12 case reports, with a total of 84 patients treated with sclerotherapy for persistent seromas. Slerosant included talc, tetracycline antibiotics, ethanol, polidocanol, erythromycin, OK-432, fibrin glue, and povidone-iodine. All agents achieved high rates of success. Repeat aspirations and instillations were easily performed when required. Complications, while uncommon, included pain, tightness or discomfort of the treated area, and infection. Conclusion: Sclerotherapy appears to be effective and safe for recurrent seromas. While a variety of sclerosing agents may be applied successfully, talc and tetracyclines remain popular choices. Because of the small scale and retrospective nature of the published literature, larger, randomized, comparative studies are necessary to assess and optimize this treatment approach.

20.
Methods Mol Biol ; 1530: 147-164, 2017.
Artigo em Inglês | MEDLINE | ID: mdl-28150202

RESUMO

Polyethylene glycol (PEG) and related polymers are often used in the solubilization and noncovalent functionalization of carbon nanomaterials by sonication. For example, carbon nanotubes are frequently sonicated with PEG-containing surfactants of the Pluronic® series or phospholipid-PEG polymers to noncovalently functionalize the nanotubes. However, PEG is very sensitive to degradation upon sonication and the degradation products can be toxic to mammalian cells and to organisms such as zebrafish embryos. It is therefore useful to have a simple and inexpensive method to determine the extent of potential PEG sonolysis, as described in this chapter. Intact PEG polymers and degraded fragments are resolved on sodium dodecyl sulfate polyacrylamide gels by electrophoresis and visualized by staining with barium iodine (BaI2). Digitized images of gels are acquired using a flatbed photo scanner and the intensities of BaI2-stained PEG bands are quantified using ImageJ software. Degradation of PEG polymers after sonication is readily detected by the reduction of band intensities in gels compared to those of non-sonicated, intact PEG polymers. In addition, the approach can be used to rapidly screen various sonication conditions to identify those that might minimize PEG degradation to acceptable levels.


Assuntos
Nanotubos de Carbono , Polietilenoglicóis , Eletroforese em Gel de Poliacrilamida , Nanotubos de Carbono/química , Polietilenoglicóis/química , Sonicação , Coloração e Rotulagem
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