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1.
Nat Mater ; 22(4): 429-433, 2023 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-36894771

RESUMO

The lowest-lying fundamental excitation of an incommensurate charge-density-wave material is believed to be a massless phason-a collective modulation of the phase of the charge-density-wave order parameter. However, long-range Coulomb interactions should push the phason energy up to the plasma energy of the charge-density-wave condensate, resulting in a massive phason and fully gapped spectrum1. Using time-domain terahertz emission spectroscopy, we investigate this issue in (TaSe4)2I, a quasi-one-dimensional charge-density-wave insulator. On transient photoexcitation at low temperatures, we find the material strikingly emits coherent, narrowband terahertz radiation. The frequency, polarization and temperature dependences of the emitted radiation imply the existence of a phason that acquires mass by coupling to long-range Coulomb interactions. Our observations underscore the role of long-range interactions in determining the nature of collective excitations in materials with modulated charge or spin order.

2.
Phys Rev Lett ; 131(7): 076901, 2023 Aug 18.
Artigo em Inglês | MEDLINE | ID: mdl-37656841

RESUMO

We report ultrafast x-ray scattering experiments of the quasi-1D charge density wave (CDW) material (TaSe_{4})_{2}I following ultrafast infrared photoexcitation. From the time-dependent diffraction signal at the CDW sidebands we identify a 0.11 THz amplitude mode derived primarily from a transverse acoustic mode of the high-symmetry structure. From our measurements we determine that this mode interacts with the valence charge indirectly through another collective mode, and that the CDW system in (TaSe_{4})_{2}I has a composite nature supporting multiple dynamically active structural degrees of freedom.

3.
Langenbecks Arch Surg ; 406(5): 1341-1351, 2021 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-33416987

RESUMO

OBJECTIVE: The safety and role of emergency (EA) versus interval appendicectomy (IA) for appendicular abscess and phlegmon remains debatable with no optimal strategy identified. The aim of this systematic review and meta-analysis is to evaluate outcomes of managing appendicular abscesses and phlegmon with emergency or interval appendicectomy. METHODS: We conducted a systematic search of electronic databases using key terms including 'appendicular abscess', 'appendicular phlegmon' and 'interval appendicectomy'. Randomised controlled trials and observational studies comparing the two management approaches were included. Operative time, post-operation complication, unplanned bowel resection, rate of surgical site infection, post-operative length of stay and overall mortality rate were evaluated. RESULTS: We identified six studies (2 RCTs and 4 observational studies) with a total of 9264 patients of whom (n = 1352) underwent IA, and (n 7912) underwent EA. The EA group was associated with statistically significant unplanned bowel resection (OR 0.55, 95% CI [0.33-0.90], P = 0.02) and longer total operating time (MD - 14.11, 95% CI [- 18.26-- 9.96] P = 0.00001). However, the following parameters were compared for both EA and IA groups; there were no significant statistical differences: surgical site infection (OR 0.49, 95% CI [0.17-1.38], P = 0.18), post-operative intra-abdominal collection (RD - 0.01, 95% CI [- 0.04-0.01], P = 0.29), total length of hospital stay (MD 1.83, 95% CI [- 0.19-3.85], P = 0.08), post-operative length of hospital stay (MD - 0.27, 95% CI [- 3.66-3.13], P = 0.88) and mortality rate (MD - 0.27, 95% CI [- 3.66-3.13], P = 0.66). CONCLUSION: Emergency operation for appendicular abscess and phlegmon may lead to a higher rate of reported morbidity when compared with interval appendicectomy. Although emergency appendicectomy performed for appendicular abscess and phlegmon is a feasible and safe operative approach, it is associated with significantly increased operative time and unplanned bowel resection (ileocolic and right hemicolectomies) compared to interval appendicectomy.


Assuntos
Apendicite , Laparoscopia , Abscesso/cirurgia , Apendicectomia/efeitos adversos , Apendicite/cirurgia , Celulite (Flegmão)/cirurgia , Humanos , Tempo de Internação
4.
Phys Rev Lett ; 124(3): 037203, 2020 Jan 24.
Artigo em Inglês | MEDLINE | ID: mdl-32031844

RESUMO

NiNb_{2}O_{6} is an almost ideal realization of a 1D spin-1 ferromagnetic Heisenberg chain compound with weak unidirectional anisotropy. Using time-domain THz spectroscopy, we measure the low-energy electrodynamic response of NiNb_{2}O_{6} as a function of temperature and external magnetic field. At low temperatures, we find a magnonlike spin excitation, which corresponds to the lowest energy excitation at q∼0. At higher temperatures, we unexpectedly observe a temperature-dependent renormalization of the spin-excitation energy, which has a strong dependence on field direction. Using theoretical arguments, exact diagonalizations, and finite temperature dynamical Lanczos calculations, we construct a picture of magnon-magnon interactions that naturally explains the observed renormalization. We show how magnetic field strength and direction may be used to directly tune the sign of the magnon-magnon interaction. This unique scenario is a consequence of the spin-1 nature and has no analog in the more widely studied spin-1/2 systems.

5.
Int J Mol Sci ; 21(15)2020 Jul 27.
Artigo em Inglês | MEDLINE | ID: mdl-32726923

RESUMO

Colorectal cancer (CRC) is a leading cause of death worldwide, despite progress made in detection and management through surgery, chemotherapy, radiotherapy, and immunotherapy. Novel therapeutic agents have improved survival in both the adjuvant and advanced disease settings, albeit with an increased risk of toxicity and cost. However, metastatic disease continues to have a poor long-term prognosis and significant challenges remain due to late stage diagnosis and treatment failure. Biomarkers are a key tool in early detection, prognostication, survival, and predicting treatment response. The past three decades have seen advances in genomics and molecular pathology of cancer biomarkers, allowing for greater individualization of therapy with a positive impact on survival outcomes. Clinically useful predictive biomarkers aid clinical decision making, such as the presence of KRAS gene mutations predicting benefit from epidermal growth factor receptor (EGFR) inhibiting antibodies. However, few biomarkers have been translated into clinical practice highlighting the need for further investigation. We review a range of protein, DNA and RNA-based biomarkers under investigation for diagnostic, predictive, and prognostic properties for CRC. In particular, long non-coding RNAs (lncRNA), have been investigated as biomarkers in a range of cancers including colorectal cancer. Specifically, we evaluate the potential role of lncRNA plasmacytoma variant translocation 1 (PVT1), an oncogene, as a diagnostic, prognostic, and therapeutic biomarker in colorectal cancer.


Assuntos
Biomarcadores Tumorais , Neoplasias Colorretais , Proteínas Proto-Oncogênicas p21(ras) , RNA Longo não Codificante , RNA Neoplásico , Biomarcadores Tumorais/genética , Biomarcadores Tumorais/metabolismo , Neoplasias Colorretais/diagnóstico , Neoplasias Colorretais/genética , Neoplasias Colorretais/metabolismo , Neoplasias Colorretais/patologia , Receptores ErbB/genética , Receptores ErbB/metabolismo , Humanos , Prognóstico , Proteínas Proto-Oncogênicas p21(ras)/genética , Proteínas Proto-Oncogênicas p21(ras)/metabolismo , RNA Longo não Codificante/genética , RNA Longo não Codificante/metabolismo , RNA Neoplásico/genética , RNA Neoplásico/metabolismo
6.
Phys Rev Lett ; 122(2): 027003, 2019 Jan 18.
Artigo em Inglês | MEDLINE | ID: mdl-30720319

RESUMO

Overdoped high-temperature cuprate superconductors have often been understood within the standard BCS framework of superconductivity. However, measurements in a variety of overdoped cuprates indicate that the superfluid density is much smaller than expected from BCS theory and decreases smoothly to zero as the doping is increased. Here, we combine time-domain THz spectroscopy with kHz range mutual inductance measurements on the same overdoped La_{2-x}Sr_{x}CuO_{4} films to determine the total, superfluid, and uncondensed spectral weight as a function of doping. A significant fraction of the carriers remains uncondensed in a wide Drude-like peak as T→0, while the superfluid density remains linear in temperature. These observations are seemingly inconsistent with existing, realistic theories of impurity scattering suppressing the superfluid density in a BCS-like d-wave superconductor. Our large measurement frequency range gives us a unique look at the low frequency spectral weight distribution, which may suggest the presence of quantum phase fluctuations as the critical doping is approached.

7.
Phys Rev Lett ; 122(1): 017002, 2019 Jan 11.
Artigo em Inglês | MEDLINE | ID: mdl-31012661

RESUMO

Epitaxial bilayer films of Bi(110) and Ni host a time-reversal symmetry breaking superconducting order with an unexpectedly high transition temperature T_{c}=4.1 K. Using time-domain THz spectroscopy, we measure the low energy electrodynamic response of a Bi/Ni bilayer thin film from 0.2 to 2 THz as a function of temperature and magnetic field. We analyze the data in the context of a Bardeen-Cooper-Schrieffer-like superconductor with a finite normal-state scattering rate. In a zero magnetic field, all states in the film become fully gapped, providing important constraints into possible pairing symmetries. Our data appear to rule out the odd-frequency pairing that is natural for many ferromagnetic-superconductor interfaces. By analyzing the magnetic field-dependent response in terms of a pair-breaking parameter, we determine that superconductivity develops over the entire bilayer sample which may point to the p-wave like nature of unconventional superconductivity.

8.
Nano Lett ; 18(1): 223-228, 2018 01 10.
Artigo em Inglês | MEDLINE | ID: mdl-29239177

RESUMO

The valley pseudospin in monolayer transition metal dichalcogenides (TMDs) has been proposed as a new way to manipulate information in various optoelectronic devices. This relies on a large valley polarization that remains stable over long time scales (hundreds of nanoseconds). However, time-resolved measurements report valley lifetimes of only a few picoseconds. This has been attributed to mechanisms such as phonon-mediated intervalley scattering and a precession of the valley pseudospin through electron-hole exchange. Here we use transient spin grating to directly measure the valley depolarization lifetime in monolayer MoSe2. We find a fast valley decay rate that scales linearly with the excitation density at different temperatures. This establishes the presence of strong exciton-exciton Coulomb exchange interactions enhancing the valley depolarization. Our work highlights the microscopic processes inhibiting the efficient use of the exciton valley pseudospin in monolayer TMDs.

9.
Phys Rev Lett ; 114(1): 017203, 2015 Jan 09.
Artigo em Inglês | MEDLINE | ID: mdl-25615500

RESUMO

We use ultrafast optical spectroscopy to observe binding of charged single-particle excitations (SE) in the magnetically frustrated Mott insulator Na(2)IrO(3). Above the antiferromagnetic ordering temperature (T(N)) the system response is due to both Hubbard excitons (HE) and their constituent unpaired SE. The SE response becomes strongly suppressed immediately below T(N). We argue that this increase in binding energy is due to a unique interplay between the frustrated Kitaev and the weak Heisenberg-type ordering term in the Hamiltonian, mediating an effective interaction between the spin-singlet SE. This interaction grows with distance causing the SE to become trapped in the HE, similar to quark confinement inside hadrons. This binding of charged particles, induced by magnetic ordering, is a result of a confinement-deconfinement transition of spin excitations. This observation provides evidence for spin liquid type behavior which is expected in Na(2)IrO(3).

10.
Nat Mater ; 12(5): 387-91, 2013 May.
Artigo em Inglês | MEDLINE | ID: mdl-23435216

RESUMO

Cuprate materials hosting high-temperature superconductivity (HTS) also exhibit various forms of charge and spin ordering whose significance is not fully understood. So far, static charge-density waves (CDWs) have been detected by diffraction probes only at particular doping levels or in an applied external field . However, dynamic CDWs may also be present more broadly and their detection, characterization and relationship with HTS remain open problems. Here we present a method based on ultrafast spectroscopy to detect the presence and measure the lifetimes of CDW fluctuations in cuprates. In an underdoped La(1.9)Sr(0.1)CuO4 film (T(c) = 26 K), we observe collective excitations of CDW that persist up to 100 K. This dynamic CDW fluctuates with a characteristic lifetime of 2 ps at T = 5 K that decreases to 0.5 ps at T = 100 K. In contrast, in an optimally doped La(1.84)Sr(0.16)CuO4 film (T(c) = 38.5 K), we detect no signatures of fluctuating CDWs at any temperature, favouring the competition scenario. This work forges a path for studying fluctuating order parameters in various superconductors and other materials.

11.
Phys Rev Lett ; 113(20): 206801, 2014 Nov 14.
Artigo em Inglês | MEDLINE | ID: mdl-25432050

RESUMO

We report on electronic transport measurements of dual-gated nanodevices of the low-carrier density topological insulator (TI) Bi_{1.5}Sb_{0.5}Te_{1.7}Se_{1.3}. In all devices, the upper and lower surface states are independently tunable to the Dirac point by the top and bottom gate electrodes. In thin devices, electric fields are found to penetrate through the bulk, indicating finite capacitive coupling between the surface states. A charging model allows us to use the penetrating electric field as a measurement of the intersurface capacitance C_{TI} and the surface state energy-density relationship µ(n), which is found to be consistent with independent angle-resolved photoemission spectroscopy measurements. At high magnetic fields, increased field penetration through the surface states is observed, strongly suggestive of the opening of a surface state band gap due to broken time-reversal symmetry.

12.
J Inherit Metab Dis ; 37(4): 483-95, 2014 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-24797558

RESUMO

The majority of human inborn errors of metabolism are fatal multisystem disorders that lack proper treatment and have a poorly understood mechanistic basis. Novel technologies are required to address this issue, and the use of zebrafish to model these diseases is an emerging field. Here we present the published zebrafish models of inborn metabolic diseases, discuss their validity, and review the novel mechanistic insights that they have provided. We also review the available methods for creating and studying zebrafish disease models, advantages and disadvantages of using this model organism, and successful examples of the use of zebrafish for drug discovery and development. Using a zebrafish to model inborn errors of metabolism in vivo, although still in its infancy, shows promise for a deeper understanding of disease pathomechanisms, onset, and progression, and also for the development of specific therapies.


Assuntos
Modelos Animais de Doenças , Erros Inatos do Metabolismo/patologia , Erros Inatos do Metabolismo/terapia , Peixe-Zebra , Animais , Descoberta de Drogas/métodos , Embrião não Mamífero , Humanos , Terapia de Alvo Molecular , Estudos de Validação como Assunto
13.
Brain ; 136(Pt 5): 1488-507, 2013 May.
Artigo em Inglês | MEDLINE | ID: mdl-23587805

RESUMO

Tripeptidyl peptidase 1 (TPP1) deficiency causes CLN2 disease, late infantile (or classic late infantile neuronal ceroid lipofuscinosis), a paediatric neurodegenerative disease of autosomal recessive inheritance. Patients suffer from blindness, ataxia, epilepsy and cognitive defects, with MRI indicating widespread brain atrophy, and profound neuron loss is evident within the retina and brain. Currently there are no effective therapies for this disease, which causes premature death in adolescence. Zebrafish have been successfully used to model a range of neurological and behavioural abnormalities. The aim of this study was to characterize the pathological and functional consequences of Tpp1 deficiency in zebrafish and to correlate these with human CLN2 disease, thereby providing a platform for drug discovery. Our data show that homozygous tpp1(sa0011) mutant (tpp1(sa0011)(-/-)) zebrafish display a severe, progressive, early onset neurodegenerative phenotype, characterized by a significantly small retina, a small head and curved body. The mutant zebrafish have significantly reduced median survival with death occurring 5 days post-fertilization. As in human patients with CLN2 disease, mutant zebrafish display storage of subunit c of mitochondrial ATP-synthase, hypertrophic lysosomes as well as localized apoptotic cell death in the retina, optic tectum and cerebellum. Further neuropathological phenotypes of these mutants provide novel insights into mechanisms of pathogenesis in CLN2 disease. Secondary neurogenesis in the retina, optic tectum and cerebellum is impaired and axon tracts within the spinal cord, optic nerve and the posterior commissure are disorganized, with the optic nerve failing to reach its target. This severe neurodegenerative phenotype eventually results in functional motor impairment, but this is preceded by a phase of hyperactivity that is consistent with seizures. Importantly, both of these locomotion phenotypes can be assayed in an automated manner suitable for high-throughput studies. Our study provides proof-of-principle that tpp1(sa0011)(-/-) mutants can utilize the advantages of zebrafish for understanding pathogenesis and drug discovery in CLN2 disease and other epilepsies.


Assuntos
Aminopeptidases/deficiência , Proliferação de Células , Dipeptidil Peptidases e Tripeptidil Peptidases/deficiência , Progressão da Doença , Lipofuscinoses Ceroides Neuronais/enzimologia , Lipofuscinoses Ceroides Neuronais/patologia , Serina Proteases/deficiência , Aminopeptidases/genética , Aminopeptidases/fisiologia , Animais , Animais Geneticamente Modificados , Dipeptidil Peptidases e Tripeptidil Peptidases/genética , Dipeptidil Peptidases e Tripeptidil Peptidases/fisiologia , Modelos Animais de Doenças , Inibidores do Crescimento/deficiência , Inibidores do Crescimento/genética , Inibidores do Crescimento/fisiologia , Humanos , Atividade Motora/fisiologia , Doenças Neurodegenerativas/enzimologia , Doenças Neurodegenerativas/genética , Doenças Neurodegenerativas/patologia , Lipofuscinoses Ceroides Neuronais/genética , Serina Proteases/genética , Serina Proteases/fisiologia , Tripeptidil-Peptidase 1 , Peixe-Zebra
14.
Nat Commun ; 15(1): 550, 2024 Jan 16.
Artigo em Inglês | MEDLINE | ID: mdl-38228584

RESUMO

Symmetry-protected topological crystalline insulators (TCIs) have primarily been characterized by their gapless boundary states. However, in time-reversal- ([Formula: see text]-) invariant (helical) 3D TCIs-termed higher-order TCIs (HOTIs)-the boundary signatures can manifest as a sample-dependent network of 1D hinge states. We here introduce nested spin-resolved Wilson loops and layer constructions as tools to characterize the intrinsic bulk topological properties of spinful 3D insulators. We discover that helical HOTIs realize one of three spin-resolved phases with distinct responses that are quantitatively robust to large deformations of the bulk spin-orbital texture: 3D quantum spin Hall insulators (QSHIs), "spin-Weyl" semimetals, and [Formula: see text]-doubled axion insulator (T-DAXI) states with nontrivial partial axion angles indicative of a 3D spin-magnetoelectric bulk response and half-quantized 2D TI surface states originating from a partial parity anomaly. Using ab-initio calculations, we demonstrate that ß-MoTe2 realizes a spin-Weyl state and that α-BiBr hosts both 3D QSHI and T-DAXI regimes.

15.
PLoS One ; 18(2): e0279032, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-36812259

RESUMO

The coronavirus disease 2019 (COVID-19) stances an incredible impact on the quality of life and denigrates the physical and mental health of the patients. This cross-sectional study aimed to assess the health-related quality of life (HRQOL) of COVID-19 patients. We conducted this study at the National Institute of Preventive and Social Medicine (NIPSOM) of Bangladesh for the period of June to November 2020. All the COVID-19 patients diagnosed by real-time reverse transcriptase-polymerase chain reaction (RT-PCR) assay in July 2020 formed the sampling frame. The study enrolled 1204 adult (aged >18 years) COVID-19 patients who completed a one-month duration of illness after being RT-PCR positive. The patients were interviewed with the CDC HRQOL-14 questionnaire to assess HRQOL. Data were collected by telephone interview on the 31st day of being diagnosed and by reviewing medical records using a semi-structured questionnaire and checklist. Around two-thirds (72.3%) of the COVID-19 patients were males and a half (50.2%) were urban residents. In 29.8% of patients, the general health condition was not good. The mean (±SD) duration of physical illness and mental illness was 9.83(±7.09) and 7.97(±8.12) days, respectively. Most of the patients (87.0%) required help with personal care, and 47.8% required assistance with routine needs. The mean duration of 'healthy days' and 'feeling very healthy' was significantly lower in patients with increasing age, symptoms, and comorbidity. The mean duration of 'usual activity limitation', 'health-related limited activity', 'feeling pain/worried', and 'not getting enough rest' were significantly higher among patients' having symptoms and comorbidity. 'Not so good' health condition was significantly higher in females (OR = 1.565, CI = 1.01-2.42) and those having a symptom (OR = 32.871, CI = 8.06-134.0) of COVID-19 and comorbidity (OR = 1.700, CI = 1.26-2.29). Mental distress was significantly higher among females (OR = 1.593, CI = 1.03-2.46) and those having a symptom (OR = 4.887, CI = 2.58-9.24). Special attention should be given to COVID-19 patients having symptoms and comorbidity to restore their general health, quality of life, and daily activities.


Assuntos
COVID-19 , Transtornos Mentais , Masculino , Feminino , Humanos , Adulto , Qualidade de Vida , Estudos Transversais , Bangladesh
16.
Lancet Reg Health Southeast Asia ; 11: 100131, 2023 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-36575773

RESUMO

Background: COVID-19 pandemic imposed a devastating effect on the psychological health of health professionals as they worked nonstop to withstand the hardship of the pandemic. The present study intended to determine the post-traumatic stress disorders (PTSD) and coping strategies among health professionals during the COVID-19 pandemic in Bangladesh. Methods: This country-wide cross-sectional study was conducted from July to December 2021 among 1394 health professionals (596 physicians, 713 nurses, 85 medical technologists) who served COVID-19 patients at the secondary, tertiary, and specialized government healthcare facilities in Bangladesh and completed at least one month after exposure to COVID-19 patient-care. Data were collected through face-to-face interviews using a semi-structured questionnaire and analyzed by SPSS software. All the ethical issues were maintained strictly. Findings: Most of the participants, 877 (62.9%) [95% CI: 60.3-65.5], were female, and 327 (23.5%) [95% CI: 21.3-25.8] developed PTSD. Females (AOR:1.42 [95% CI: 1.083-1.868] p = 0.011), having an elderly family member (AOR:1.515 [95% CI: 1.173-1.956] p = 0.0014), working in specialized hospitals (AOR:2.685 [95% CI: 1.928-3.739] p < 0.001), and working ≥8 hours/day (AOR:1.897 [95% CI: 1.350-2.666] p = 0.0002) had higher odds of developing PTSD. Most of the participants adopted spiritual approaches 96 (29.4%) [24.5-34.6] and distraction by watching TV/YouTube 59 (18.0%) [14.0-22.6] as coping strategies. Interpretation: The study findings would be helpful for health policymakers and managers to develop comprehensive measures for restoring the mental well-being of health professionals by alleviating PTSD induced by a pandemic like COVID-19. Funding: The study got funding from the Directorate General of Medical Education under the Ministry of Health and Family Welfare, Bangladesh.

17.
Cureus ; 14(1): e21446, 2022 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-35223231

RESUMO

Introduction Acute appendicitis (AA) is one of the most common acute general surgical presentations affecting 7% of the population at some point in their lifetime. The ability to assess the risk of complicated appendicitis (CA) from uncomplicated appendicitis (UA) in acute appendicitis (AA) could reduce the associated morbidity and mortality. The value of platelet lymphocyte ratio (PLR) as an inflammatory marker increases when its fluctuations are interpreted along with other complementary hematologic indices, such as neutrophil-to-lymphocyte ratio (NLR), which provides additional information about the disease activity. Hence, we postulated that NLR and/or PLR could serve as a potential surrogate marker in assessing the severity of AA. Aim This study aims to investigate the use of PLR and/or NLR as a surrogate biomarker in differentiating uncomplicated from complicated appendicitis. Material and methods This retrospective study was conducted at Russells Hall Hospital from January 1, 2017, to December 31, 2020. Data of all patients over age 16 years that had histologically confirmed appendicitis were retrieved. NLR and PLR were calculated from the admission hemogram, and the ratios were compared between uncomplicated (UA) or complicated appendicitis (CA). Cut-off values were calculated using the summarized ROC curve; in addition, the sensitivity and specificity with 95% confidence intervals were determined using SPSS 25.0 (IBM Corp., Armonk, NY). Results A total of 799 patients were analyzed, of which 469 (58.7%) were female. The median age was 31.2 years. The difference between NLR and PLR within the two appendicitis groups was significant (P=0.05; Kruskal-Wallis). Cohen's kappa (degree of inter-rater agreement) between NLR and PLR showed a moderate agreement of 0.589 (P<0.001). We equally demonstrated an exponential relationship between PLR and NLR (R2 =0.510, P<0.05). For UA, the area under the curve (AUC) and the cut-off for NLR and PLR were 0.715, 4.75 with a confidence interval (CI) of 0.678-0.653 and 0.632, 155 with a CI of 0.591-0.672, respectively. For CA, using NLR and PLR, the AUC and cut-off were 0.727, 6.96 with a CI of 0.687-0.768 and 0.653, 180.5 with a CI of 0.602-0.703, respectively; all were significant with a P of <0.001. Conclusion NLR and PLR are a reliable, less cumbersome surrogate biomarker for assessing the severity of acute appendicitis.

18.
Cureus ; 14(8): e28619, 2022 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-36185898

RESUMO

Introduction The ability to predict risk of perforation in acute appendicitis (AA) could direct timely management and reduce morbidity. Platelet-to-lymphocyte ratio (PLR) and neutrophil-to-lymphocyte ratio (NLR) are surrogate severity markers in infections. This study investigates the use of PLR and NLR as a marker for distinguishing uncomplicated (UA) and complicated appendicitis (CA) in children. Materials and methods This retrospective single-center study collected data between January 1, 2014, and December 31, 2020. Children between five and 17 years of age with histologically confirmed appendicitis were included. Cut-off values for NLR and PLR were determined by employing the receiver operating characteristic (ROC) curve with sensitivity and specificity in addition to regression analysis. Results A total of 701 patients were included with a median age of 13 years. Out of which 52% of the cohort was female. The difference between the NLR and PLR ratios between UA and CA was significant (p=0.05, Kruskal-Wallis). For UA, the area under the ROC curve (AUC) and cut-off for NLR and PLR were 0.741, 3.80 with 95% CI of 0.701-0.781 and 0.660, 149.25 with 95% CI of 0.618-0.703, respectively. In CA, using NLR and PLR, AUC and cut-off were 0.776, 8.86 with 95%CI of 0.730-0.822 and 0.694, 193.67 with 95%CI of 0.634-0.755, respectively. All were significant with p<0.001. Conclusions NLR and PLR are reliable, synergistic markers predicting complicated appendicitis which can guide non-operative management in children.

19.
J Cardiovasc Surg (Torino) ; 63(6): 664-673, 2022 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-36239927

RESUMO

INTRODUCTION: Malignancies involving the inferior vena cava (IVC) have historically been considered not amendable to surgery. More recently, involvement of the IVC by neoplastic processes in the kidney, liver or in the retroperitoneum can be managed successfully. EVIDENCE ACQUISITION: In this systematic review we summarize the current evidence regarding the surgical management of the IVC in cases of involvement in neoplastic processes. Current literature was searched, and studies selected on the base of the PRISMA guidelines. Evidence was synthesized in narrative form due to heterogeneity of studies. EVIDENCE SYNTHESIS: Renal cell carcinoma accounts for the greatest proportion of studied patients and can be managed with partial or complete vascular exclusion of the IVC, thrombectomy and direct closure or patch repair with good oncological prognosis. Hepatic malignancies or metastases may involve the IVC, and the joint expertise of hepatobiliary and vascular surgeons has developed various strategies, according to the location of tumor and the need to perform a complete vascular exclusion above the hepatic veins. In retroperitoneal lymph node dissection, the IVC can be excised en-block to guarantee better oncological margins. Also, in retroperitoneal sarcomas not arising from the IVC a vascular substitution may be required to improve the overall survival by clearing all the neoplastic cells in the retroperitoneum. Leiomyoma can have a challenging presentation with involvement of the IVC requiring either thrombectomy, partial or complete substitution, with good oncological outcomes. CONCLUSIONS: A multidisciplinary approach with specialist expertise is required when dealing with IVC involvement in surgical oncology. Multiple techniques and strategies are required to deliver the most efficient care and achieve the best possible overall survival. The main aim of these procedures must be the complete clearance of all neoplastic cells and achievement of a safe margin according to the perioperative treatment strategy.


Assuntos
Carcinoma de Células Renais , Neoplasias Renais , Humanos , Veia Cava Inferior/diagnóstico por imagem , Veia Cava Inferior/cirurgia , Veia Cava Inferior/patologia , Carcinoma de Células Renais/patologia , Carcinoma de Células Renais/cirurgia , Trombectomia/efeitos adversos , Espaço Retroperitoneal , Neoplasias Renais/patologia , Neoplasias Renais/cirurgia
20.
J Surg Case Rep ; 2022(7): rjac331, 2022 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-35903665

RESUMO

Solid pseudopapillary neoplasm (SPN) of the pancreas is a rare malignancy with a low malignant potential and strong female preponderance. Diagnosis during pregnancy is extraordinary, and management must consider the risks to the mother and foetus of tumour growth and rupture. A large 35-cm SPN was identified on magnetic resonance imaging (MRI) in a 24-year-old woman at 6 weeks of gestation following presentation with an abdominal mass. Surgery was delayed to allow the foetus to reach as close to term as possible because surveillance MRIs showed incremental mass growth. Emergency c-section was undertaken at 35 weeks of gestation due to persistent tachycardia and suspected haemorrhage into the tumour. A Hb of 70 g/l post-delivery despite four units of RBCs and an albumin of 11 g/l necessitated urgent multivisceral surgery. Surgical resection is the mainstay of treatment for SPN. However, the strategy of choice during pregnancy remains undetermined, with more recent reports delaying surgery until post-partum.

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