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1.
Nature ; 602(7896): 245-250, 2022 02.
Artigo em Inglês | MEDLINE | ID: mdl-35140387

RESUMO

The kagome lattice1, which is the most prominent structural motif in quantum physics, benefits from inherent non-trivial geometry so that it can host diverse quantum phases, ranging from spin-liquid phases, to topological matter, to intertwined orders2-8 and, most rarely, to unconventional superconductivity6,9. Recently, charge sensitive probes have indicated that the kagome superconductors AV3Sb5 (A = K, Rb, Cs)9-11 exhibit unconventional chiral charge order12-19, which is analogous to the long-sought-after quantum order in the Haldane model20 or Varma model21. However, direct evidence for the time-reversal symmetry breaking of the charge order remains elusive. Here we use muon spin relaxation to probe the kagome charge order and superconductivity in KV3Sb5. We observe a noticeable enhancement of the internal field width sensed by the muon ensemble, which takes place just below the charge ordering temperature and persists into the superconducting state. Notably, the muon spin relaxation rate below the charge ordering temperature is substantially enhanced by applying an external magnetic field. We further show the multigap nature of superconductivity in KV3Sb5 and that the [Formula: see text] ratio (where Tc is the superconducting transition temperature and λab is the magnetic penetration depth in the kagome plane) is comparable to those of unconventional high-temperature superconductors. Our results point to time-reversal symmetry-breaking charge order intertwining with unconventional superconductivity in the correlated kagome lattice.

2.
Nature ; 612(7939): 228-231, 2022 12.
Artigo em Inglês | MEDLINE | ID: mdl-36477127

RESUMO

Gamma-ray bursts (GRBs) are flashes of high-energy radiation arising from energetic cosmic explosions. Bursts of long (greater than two seconds) duration are produced by the core-collapse of massive stars1, and those of short (less than two seconds) duration by the merger of compact objects, such as two neutron stars2. A third class of events with hybrid high-energy properties was identified3, but never conclusively linked to a stellar progenitor. The lack of bright supernovae rules out typical core-collapse explosions4-6, but their distance scales prevent sensitive searches for direct signatures of a progenitor system. Only tentative evidence for a kilonova has been presented7,8. Here we report observations of the exceptionally bright GRB 211211A, which classify it as a hybrid event and constrain its distance scale to only 346 megaparsecs. Our measurements indicate that its lower-energy (from ultraviolet to near-infrared) counterpart is powered by a luminous (approximately 1042 erg per second) kilonova possibly formed in the ejecta of a compact object merger.


Assuntos
Astros Celestes
3.
Phys Rev Lett ; 132(15): 150606, 2024 Apr 12.
Artigo em Inglês | MEDLINE | ID: mdl-38682979

RESUMO

We report on the first realization of a novel neutral atom qubit encoded in the spin-orbit coupled metastable states ^{3}P_{0} and ^{3}P_{2} of a single ^{88}Sr atom trapped in an optical tweezer. Raman coupling of the qubit states promises rapid single-qubit rotations on par with the fast Rydberg-mediated two-body gates. We demonstrate preparation, readout, and coherent control of the qubit. In addition to driving Rabi oscillations bridging an energy gap of more than 17 THz using a pair of phase-locked clock lasers, we also carry out Ramsey spectroscopy to extract the transverse qubit coherence time T_{2}. When the tweezer is tuned into magic trapping conditions, which is achieved in our setup by tuning the tensor polarizability of the ^{3}P_{2} state via an external control magnetic field, we measure T_{2}=1.2 ms. A microscopic quantum mechanical model is used to simulate our experiments including dominant noise sources. We identify the main constraints limiting the observed coherence time and project improvements to our system in the immediate future. Our Letter opens the door for a so-far-unexplored qubit encoding concept for neutral atom-based quantum computing.

4.
J Med Syst ; 48(1): 31, 2024 Mar 15.
Artigo em Inglês | MEDLINE | ID: mdl-38488884

RESUMO

Intraoperative cardiopulmonary variables are well-known predictors of postoperative pulmonary complications (PPC), traditionally quantified by median values over the duration of surgery. However, it is unknown whether cardiopulmonary instability, or wider intra-operative variability of the same metrics, is distinctly associated with PPC risk and severity. We leveraged a retrospective cohort of adults (n = 1202) undergoing major non-cardiothoracic surgery. We used multivariable logistic regression to evaluate the association of two outcomes (1)moderate-or-severe PPC and (2)any PPC with two sets of exposure variables- (a)variability of cardiopulmonary metrics (inter-quartile range, IQR) and (b)median intraoperative cardiopulmonary metrics. We compared predictive ability (receiver operating curve analysis, ROC) and parsimony (information criteria) of three models evaluating different aspects of the intra-operative cardiopulmonary metrics: Median-based: Median cardiopulmonary metrics alone, Variability-based: IQR of cardiopulmonary metrics alone, and Combined: Medians and IQR. Models controlled for peri-operative/surgical factors, demographics, and comorbidities. PPC occurred in 400(33%) of patients, and 91(8%) experienced moderate-or-severe PPC. Variability in multiple intra-operative cardiopulmonary metrics was independently associated with risk of moderate-or-severe, but not any, PPC. For moderate-or-severe PPC, the best-fit predictive model was the Variability-based model by both information criteria and ROC analysis (area under the curve, AUCVariability-based = 0.74 vs AUCMedian-based = 0.65, p = 0.0015; AUCVariability-based = 0.74 vs AUCCombined = 0.68, p = 0.012). For any PPC, the Median-based model yielded the best fit by information criteria. Predictive accuracy was marginally but not significantly higher for the Combined model (AUCCombined = 0.661) than for the Median-based (AUCMedian-based = 0.657, p = 0.60) or Variability-based (AUCVariability-based = 0.649, p = 0.29) models. Variability of cardiopulmonary metrics, distinct from median intra-operative values, is an important predictor of moderate-or-severe PPC.


Assuntos
Pulmão , Complicações Pós-Operatórias , Adulto , Humanos , Estudos Retrospectivos , Estudos Prospectivos , Fatores de Risco , Complicações Pós-Operatórias/epidemiologia
5.
Med J Armed Forces India ; 79(3): 267-274, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37193528

RESUMO

Background: Carbapenemase producing gram-negative bacteria (GNB) has become a huge problem in majority of tertiary care centers worldwide. They are associated with very high morbidity and mortality rates, especially when they cause invasive infections. Therefore, rapid detection of these organisms is very important for prompt and adequate antibiotic therapy as well as infection control. The aim of this study was rapid detection of carbapenemase genes and thereby likely carbapenem resistance, 24-48 hours in advance, directly from the positive-flagged blood culture bottles using CHROMagar and Xpert® Carba-R. Methods: Aspirate from positively flagged blood culture bottles was subjected to differential centrifuge. All gram-negative bacilli on gram stain from the deposit were processed in Xpert® Carba-R and inoculated on CHROMagar. The presence of genes and growth on CHROMagar was compared with carbapenem resistance on VITEK-2 Compact. Results: A total of 119 GNB isolates were processed. One or more of the carbapenemase genes were detected in 80 isolates. On comparison with VITEK-2 result, 92 samples showed concordance for carbapenem resistance 48 hours in advance. There was discordance in 21 isolates with 12 major errors and 09 minor errors. The sensitivity of direct Xpert® Carba-R test for rapid detection of carbapenem resistance, 48 hours in advance, was 81.42%. The sensitivity of direct CHROMagar test for accurate detection of carbapenem resistance, 24 hours in advance, was 92.06%. Conclusion: The ability to detect carbapenem resistance with very high accuracy, 48 hours in advance, helps in appropriate antibiotic therapy and implementation of effective infection control practices.

6.
Lett Appl Microbiol ; 74(2): 159-184, 2022 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-34402087

RESUMO

Bacterial species capable of performing both nitrification and denitrification in a single vessel under similar conditions have gained significance in the wastewater treatment scenario considering their unique character of performing the above reactions under heterotrophic and aerobic conditions respectively. Such a novel strategy often referred to as simultaneous nitrification and denitrification (SND) has a tremendous potential in dealing with various wastewaters having low C : N content, considering that the process needs very little or no external carbon source and oxygen supply thus adding to its cost-effective and environmentally friendly nature. Though like other micro-organisms, heterotrophic nitrifiers and aerobic denitrifiers convert inorganic or organic nitrogen-containing substances into harmless dinitrogen gas in the wastewater, their ecophysiological role in the global nitrogen cycle is still not fully understood. Attempts to highlight the role played by the heterotrophic nitrifiers and aerobic denitrifiers in dealing with nitrogen pollution under various environmental operating conditions will help in developing a mechanistic understanding of the SND process to address the issues faced by the traditional methods of aerobic autotrophic nitrification-anaerobic heterotrophic denitrification.


Assuntos
Nitrificação , Purificação da Água , Aerobiose , Desnitrificação , Nitrogênio , Águas Residuárias
7.
J Postgrad Med ; 68(2): 112-114, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35381752

RESUMO

Sialadenoma papilliferum (SP) is a rare benign tumor usually occurring in the minor salivary glands. Only two cases of malignant transformation of SP and an occasional case of dysplasia in SP have been reported in the literature till now. We report a case of SP of a minor salivary gland in a middle-aged male where the exophytic component retained the histomorphological features of SP while the endophytic component displayed characteristics of a mucoepidermoid carcinoma. Malignant change in sialadenoma papilliferum is an extremely rare phenomenon that requires further research and documentation. Careful evaluation of morphologic features and reporting of more such cases is required to delineate the clinical behavior of this unusual tumor.


Assuntos
Carcinoma Mucoepidermoide , Neoplasias das Glândulas Salivares , Carcinoma Mucoepidermoide/patologia , Humanos , Masculino , Pessoa de Meia-Idade , Neoplasias das Glândulas Salivares/patologia , Glândulas Salivares Menores/patologia
8.
Rhinology ; 60(3): 188-199, 2022 Jun 01.
Artigo em Inglês | MEDLINE | ID: mdl-35901492

RESUMO

BACKGROUND: Olfactory dysfunction is a cardinal symptom of COVID-19 infection, however, studies assessing long-term olfactory dysfunction are limited and no randomised-controlled trials (RCTs) of early olfactory training have been conducted. METHODOLOGY: We conducted a prospective, multi-centre study consisting of baseline psychophysical measurements of smell and taste function. Eligible participants were further recruited into a 12-week RCT of olfactory training versus control (safety information). Patient-reported outcomes were measured using an electronic survey and BSIT at baseline and 12 weeks. An additional 1-year follow-up was open to all participants. RESULTS: 218 individuals with a sudden loss of sense of smell of at least 4-weeks were recruited. Psychophysical smell loss was observed in only 32.1%; 63 participants were recruited into the RCT. The absolute difference in BSIT improvement after 12 weeks was 0.45 higher in the intervention arm. 76 participants completed 1-year follow-up; 10/19 (52.6%) of participants with an abnormal baseline BSIT test scored below the normal threshold at 1-year, and 24/29 (82.8%) had persistent parosmia. CONCLUSIONS: Early olfactory training may be helpful, although our findings are inconclusive. Notably, a number of individuals who completed the 1-year assessment had persistent smell loss and parosmia at 1-year. As such, both should be considered important entities of long-Covid and further studies to improve management are highly warranted.


Assuntos
COVID-19 , Transtornos do Olfato , Humanos , Olfato , COVID-19/complicações , Anosmia/etiologia , Treinamento Olfativo , Transtornos do Olfato/etiologia , Transtornos do Olfato/diagnóstico
9.
Cryo Letters ; 43(5): 295-302, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-36626135

RESUMO

BACKGROUND: Cryopreservation of germplasm in liquid nitrogen is an ideal technique for the longer term storage of plant genetic material, including medicinal species. OBJECTIVE: To develop a somatic embryo production system for the medicinal species Swertia chirayita and to evaluate their potential for storage in liquid nitrogen (-196 degree C). MATERIALS AND METHODS: An efficient protocol of somatic embryogenesis was developed for the first time using leaves of in-vitro grown shoots of S. chirayita. Somatic embryos were then encapsulated in 3% sodium alginate, 0.85 M sucrose and 100 mM calcium chloride for synthetic seed production and subjected to cryopreservation. Marker medicinal compounds were determined by RP-HPLC analysis. RESULTS: A medium containing 1 mg/L 2,4-D+ 0.5 mg/L BAP+ 0.5 mg/L TDZ was found to stimulate the highest callus induction. Somatic embryos were recovered after 5 weeks, when cultured on the same media. Synthetic seeds were dehydrated and immersed in liquid nitrogen for 1 h. Cryopreserved synthetic seeds were successfully revived and germinated on MS media supplemented with 1 mg/L IBA+ 2 mg/L KN + 3 mg/L GA3 in which 93.3% somatic embryos differentiated into shoots. One month old in-vitro grown shoots from cryopreserved somatic embryos had similar marker medicinal compounds, such as amarogentin (4.72 ± 0.11 ug/mg) and mangiferin (14.54 ± 0.05 ug/mg), as control material. CONCLUSION: This protocol offers vast scope for multiplying material of an endangered medicinal herb and subsequent cryopreservation. doi.org/10.54680/fr22510110612.


Assuntos
Plantas Medicinais , Swertia , Criopreservação/métodos , Desidratação , Sementes , Nitrogênio
10.
J Assoc Physicians India ; 70(4): 11-12, 2022 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-35443438

RESUMO

The incident of End stage renal disease (ESRD) is rising rapidly worldwide. Renal transplant is the best modality of treatment, offering a better quality of life and mortality benefit, as compared with long-term dialysis. Very few patients have a live renal transplant donor, for rest, a decreased donor renal transplant is the only alternative. Deceased donor renal transplantation (DDRT) programs are only available at few government centers of India, constituting less than 5% of the total renal transplants. MATERIAL: The patients who had undergone DDRT at our center from February 2015 to February 2021 were registered in the study. The following data were recorded for all patients; age, sex, duration of ESRD, cold ischemia time, type of induction, nadir and follow -up creatinine, hemoglobin, urinary protein and complications. All recipients were followed up and investigated in the outpatient department on a regular basis as per the standard guidelines till death or graft loss, whichever is earlier. Post transplant renal allograft function was measured using serum creatinine and other parameters. OBSERVATION: During the study period 51 DDRTs were done. There were 40 male and 11 female patients. The mean age was 39.9 ± 9.8 years. The most common cause of ESRD in recipients was chronic glomerulonephritis (CGN) in 92.1 % (47). Amongst the patients, 41 (80.3%) survived, while 10 (19.6%) died post-transplant. Out of ten, 6 recipients died due to early sepsis (<3 months) and 4 died due to late sepsis (>3 months). Acute rejection was present in 17.6 % of patients. Mean post- transplant creatinine in recipients with functioning graft at discharge was 1.54 mg/dl. Graft failure was present in 7 patients out of which 2 were alive at the time of writing this paper and were on maintenance dialysis. Two patients died with a functioning graft. Delayed graft function (DGF) was seen in 13.7% (n=7) of recipients. The causes of DGF in our study included transplant renal artery thrombosis (n=2), Antibody-Mediated Rejection (n=3), mixed rejection (n=1) and Acute cellular rejection (n=1). Among those who had DGF, graft loss was seen in 57.2% (n=4). CONCLUSION: In our study, the patient survival and graft survival have been better as compared to previous studies and also the number of recipients with delayed graft function have been low. Deceased donor renal transplantation is a practical treatment modality which can drastically improve longevity and quality of life.


Assuntos
Falência Renal Crônica , Transplante de Rim , Sepse , Adulto , Creatinina , Função Retardada do Enxerto/etiologia , Função Retardada do Enxerto/terapia , Feminino , Rejeição de Enxerto/epidemiologia , Rejeição de Enxerto/etiologia , Sobrevivência de Enxerto , Humanos , Índia/epidemiologia , Falência Renal Crônica/complicações , Falência Renal Crônica/epidemiologia , Falência Renal Crônica/cirurgia , Transplante de Rim/efeitos adversos , Masculino , Pessoa de Meia-Idade , Qualidade de Vida , Estudos Retrospectivos , Sepse/complicações , Centros de Atenção Terciária , Resultado do Tratamento
11.
Med J Armed Forces India ; 78(2): 232-234, 2022 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-35463539

RESUMO

Parasitic infections of the intestine are a major health problem, which is found more prevalent in developing countries such as India. They are one of the important causes of morbidity and mortality among people all over the world. Acute amoebic appendicitis is a rare entity. We came across a case of acute appendicitis in a young pregnant woman, which revealed colonies of Entamoeba histolytica trophozoites in the mucosal epithelium and submucosal layer of the appendix with marked evidence of acute appendicitis. This report highlights acute appendicitis of amoebic origin and emphasises the importance of thorough examination of the appendix at various levels during histopathology and about the combined treatment of appendicectomy combined with antimicrobials as the treatment of choice. Appendicectomy removes the focus of infection, and antimicrobials reduce the incidence of septic complications.

12.
Med J Armed Forces India ; 78(2): 198-203, 2022 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-35463555

RESUMO

Background: Hepatitis B (HepB) is an important vaccine preventable infection among healthcare workers (HCWs). Vaccination against Hep B virus, remains the foremost preventive approach. This study aims to measure the antibody titres to Hep B surface antigen (anti-HBs) in a mixed cohort of HCWs. It also aims to study the association between time since vaccination and the anti-HBs titres thus evaluating the duration of seroprotection. Methods: A total of 200 HCWs, including nursing students (n = 112), nursing staff (n = 49), laboratory technicians (n = 30) and doctors (n = 9) who had received all three doses of the Hep B vaccine and met the inclusion criteria of having taken all three doses of vaccine were included in this study. Anti-HBs titres were estimated by bioMérieux mini VIDAS® automated immunoassay based on the principle of enzyme-linked fluorescence assay. Results: Two hundred subjects aged 19 to 52 years were included in the study; mean age was 27.29 ± 0.568 years. Duration since vaccination in the study cohort was ≤ 5 years in 149 (74.5.0%), 6-10 years in 20 (10.0%) and >10 years in 31 (15.5%) subjects. Postvaccination antibody titres were > 100 mIU/ml in 85.0%, 10-100 mIU/ml in 11.0% and ≤ 10 mIU/ml in 3.5%. There was a decline noted in antibody titres as duration after vaccination increased. Increasing age was associated with falling protective titres. Conclusion: The study revealed that majority of the HCWs had adequate anti-HBs titres and were protected after vaccination.

13.
Actas Dermosifiliogr ; 113(1): 78-81, 2022 Jan.
Artigo em Inglês, Espanhol | MEDLINE | ID: mdl-35244544

RESUMO

Malassezia folliculitis is an under-recognizedentity commonly affecting the face and upper trunk. Clinical picture mimics acne vulgaris and diagnosis is challenging at times. 10% potassium hydroxide examination is usually performed to confirm the diagnosis. This study sought to describe the dermoscopic features in Malassezia folliculitis. Patients diagnosed clinically with Malassezia folliculitis and confirmed by 10% potassium hydroxide preparation were included in the study. Dermoscopy was performed with a videodermatoscope [Dinolite AM413ZT; Polarising] from the most representative lesion. A total of 45 patients (M:F = 1:0.8 ) were recruited. All patients had monomorphic papulo-pustular lesions. Itching was present in 64.4% patients. Dermoscopy reveled folliculocentricity (100%), perilesional background erythema (100%), dotted/linear/tortous vessels (88.9%), dirty white scaling (77.8%), hypo pigmentation of hair follicle (64.4%), coiled/looped hairs (57.8%) and broken hairs (13.3%). In conclusion, dermoscopy shows typical features in Malassezia folliculitis and can serve as a office based tool for identification of this entity.

14.
Actas Dermosifiliogr ; 113(1): T78-T81, 2022 Jan.
Artigo em Inglês, Espanhol | MEDLINE | ID: mdl-35249719

RESUMO

Malassezia folliculitis is an under-recognized entity commonly affecting the face and upper trunk. Clinical picture mimics acne vulgaris and diagnosis is challenging at times. Ten percent potassium hydroxide examination is usually performed to confirm the diagnosis. This study sought to describe the dermoscopic features in Malassezia folliculitis. Patients diagnosed clinically with Malassezia folliculitis and confirmed by 10% potassium hydroxide preparation were included in the study. Dermoscopy was performed with a videodermatoscope (Dino-Lite AM413ZT; Polarizer) from the most representative lesion. A total of 45 patients (M:F=1:0.8) were recruited. All patients had monomorphic papulo-pustular lesions. Itching was present in 64.4% patients. Dermoscopy reveled folliculocentricity (100%), perilesional background erythema (100%), dotted/linear/tortous vessels (88.9%), dirty white scaling (77.8%), hypopigmentation of hair follicle (64.4%), coiled/looped hairs (57.8%) and broken hairs (13.3%). In conclusion, dermoscopy shows typical features in Malassezia folliculitis and can serve as a office-based tool for identification of this entity.

15.
Med J Armed Forces India ; 78(2): 221-231, 2022 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-35463554

RESUMO

Background: Device-associated infections (DAIs) such as ventilator associated pneumonia (VAP), central line-associated blood stream infection (CLABSI), and catheter-related urinary tract infection (CAUTI) are principal contributors to health hazard and a major preventable threat to patient safety. Robust surveillance of DAI delineates infections, pathogens, resistograms, and facilitates antimicrobial therapy, infection-control, antimicrobial stewardship, and improvement in quality of care. Methods: This prospective outcome surveillance study was conducted amongst 2067 ICU patients in a 1000-bedded teaching hospital. Clinical, laboratory, and environmental surveillance, as well as screening of health care professionals (HCPs) were conducted using the modified US Centers for Disease Control and Prevention-National Healthcare Safety Network definitions and methods. Morbidity, mortality, and health-care indices were analyzed and two-tier infection prevention and control was promulgated. Results: Mean occupancy was 95.34% for 2061 patients of 7381 patients/bed/ICU days. One hundred seventeen episodes of DAI occurred in 1258 patients of 12,882 device-days with mean device utilization ratio of 1.79. Mean rate of DAI was 7.40 per 1000 device days. Multiresistant Pseudomonas aeruginosa was most commonly followed by Acinetobacter. Mean all-cause mortality in ICU was 24.85%, whereas all-cause mortality after DAI was 9.79%. Methicillin-resistant Staphylococcus aureus prevalence was 38.46% amongst health-care professionals. Conclusion: Mean rates of VAP, CLABSI, and CAUTI were 20.69, 2.53, and 2.23 per 1000 device days comparable with Indian and global ICUs. Resolute conviction and sustained momentum in infection prevention and control is an essential step toward patient safety.

16.
Med J Armed Forces India ; 78(3): 333-338, 2022 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-35855702

RESUMO

Background: All four dengue serotypes cause infection, with one of them predominantly reported from a particular geographical region. Coinfection by more than one serotype is reported from hyperendemic regions. These coinfections are clinically more severe than infection with a single serotype. This study was carried out to detect the predominant dengue serotype and presence of coinfections. Methods: Acute-phase serum samples of patients suffering from dengue infection were collected. They were screened for the presence of IgM, IgG and NS1Ag by a rapid test. Conventional multiplex reverse transcriptase polymerase chain reaction (RT-PCR) and multiplex real-time RT-PCR assays were carried out for detection and serotyping of the dengue virus. Results: A total of 196 samples were positive by the rapid card test. Of these, 139 were NS1Ag positive, 40 were positive only for IgM, 5 were positive only for IgG and 12 samples were positive for different combinations of antigen and antibodies. All four serotypes were detected in these samples by PCR. DENV-3 was found to be most common circulating serotype. A total of 22 cases were found to have coinfection with more than one dengue serotypes. Samples having only antibodies and no antigen on rapid card test were also positive for virus by PCR. Conclusion: Prevalence of dengue co-infections is increasing. Moreover, it is important to screen for dengue virus in those samples also which do not show NS1Ag on rapid tests and have either one or both the antibodies. Real-time multiplex RT-PCR is found to be more sensitive in detecting coinfection than conventional multiplex RT-PCR.

17.
Br J Surg ; 108(5): 511-520, 2021 05 27.
Artigo em Inglês | MEDLINE | ID: mdl-33724296

RESUMO

BACKGROUND: The trial hypothesis was that, in a resource-constrained situation, short-course radiotherapy would improve treatment compliance compared with conventional chemoradiotherapy for locally advanced rectal cancer, without compromising oncological outcomes. METHODS: In this open-label RCT, patients with cT3, cT4 or node-positive non-metastatic rectal cancer were allocated randomly to 5 × 5 Gy radiotherapy and two cycles of XELOX (arm A) or chemoradiotherapy with concurrent capecitabine (arm B), followed by total mesorectal excision in both arms. All patients received a further six cycles of adjuvant chemotherapy with the XELOX regimen. The primary endpoint was treatment compliance, defined as the ability to complete planned treatment, including neoadjuvant radiochemotherapy, surgery, and adjuvant chemotherapy to a dose of six cycles. RESULTS: Of 162 allocated patients, 140 were eligible for analysis: 69 in arm A and 71 in arm B. Compliance with planned treatment (primary endpoint) was greater in arm A (63 versus 41 per cent; P = 0.005). The incidence of acute toxicities of neoadjuvant therapy was similar (haematological: 28 versus 32 per cent, P = 0.533; gastrointestinal: 14 versus 21 per cent, P = 0.305; grade III-IV: 2 versus 4 per cent, P = 1.000). Delays in radiotherapy were less common in arm A (9 versus 45 per cent; P < 0.001), and overall times for completion of neoadjuvant treatment were shorter (P < 0.001). The rates of R0 resection (87 versus 90 per cent; P = 0.554), sphincter preservation (32 versus 35 per cent; P = 0.708), pathological complete response (12 versus 10 per cent; P = 0.740), and overall tumour downstaging (75 versus 75 per cent; P = 0.920) were similar. Downstaging of the primary tumour (ypT) was more common in arm A (P = 0.044). There was no difference in postoperative complications between trial arms (P = 0.838). CONCLUSION: Reduced treatment delays and a higher rate of compliance were observed with treatment for short-course radiotherapy with consolidation chemotherapy, with no difference in early oncological surgical outcomes. In time- and resource-constrained rectal cancer units in developing countries, short-course radiotherapy should be the standard of care.


Assuntos
Quimiorradioterapia/métodos , Quimioterapia de Consolidação , Fracionamento da Dose de Radiação , Neoplasias Retais/terapia , Adenocarcinoma/mortalidade , Adenocarcinoma/patologia , Adenocarcinoma/terapia , Adulto , Protocolos de Quimioterapia Combinada Antineoplásica/uso terapêutico , Capecitabina/uso terapêutico , Países em Desenvolvimento , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Terapia Neoadjuvante , Oxaloacetatos/uso terapêutico , Cooperação do Paciente , Estudos Prospectivos , Neoplasias Retais/mortalidade , Neoplasias Retais/patologia
18.
J Gen Intern Med ; 36(6): 1613-1621, 2021 06.
Artigo em Inglês | MEDLINE | ID: mdl-33140277

RESUMO

BACKGROUND: Chronic kidney disease (CKD) is a leading cause of healthcare morbidity, utilization, and expenditures nationally, and caring for late-stage CKD populations is complex. Improving health system efficiency could mitigate these outcomes and, in the COVID-19 era, reduce risks of viral exposure. OBJECTIVE: As part of a system-wide transformation to improve healthcare value among populations with high healthcare utilization and morbidity, UCLA Health evaluated a new patient-centered approach that we hypothesized would reduce inpatient utilization for CKD patients. DESIGN: For 18 months in 2015-2016 and 12 months in 2017, we conducted an interrupted time series regression analysis to evaluate the intervention's impact on inpatient utilization. We used internal electronic health records and claims data across six payers. PARTICIPANTS: A total of 1442 stage 4-5 CKD patients at a large academic medical center. INTERVENTION: Between October and December 2016, the organization implemented a Population Health Value CKD intervention for the CKD stages 4-5 population. A multispecialty leadership team risk stratified the population and identified improvement opportunities, redesigned multispecialty care coordination pathways across settings, and developed greater ambulatory infrastructure to support care needs. MAIN MEASURES: Outcomes included utilization of hospitalizations, emergency department (ED) visits, inpatient bed days, and 30-day all-cause readmissions. KEY RESULTS: During the 12 months following intervention implementation, the monthly estimated rate of decline for hospitalizations was 5.4% (95% CI: 3.4-7.4%), which was 3.4 percentage points faster than the 18-month pre-intervention decline of 2.0% (95% CI: 1.0-2.2%) per month (p = 0.004). Medicare CKD patients' monthly ED visit rate of decline was 3.0% (95% CI: 1.2-4.8%) after intervention, which was 2.6 percentage points faster than the pre-intervention decline of 0.4% (95% CI: - 0.8 to 1.6%) per month (p = 0.02). CONCLUSIONS: By creating care pathways that link primary and specialty care teams across settings with increased ambulatory infrastructure, healthcare systems have potential to reduce inpatient healthcare utilization.


Assuntos
COVID-19 , Saúde da População , Insuficiência Renal Crônica , Idoso , Serviço Hospitalar de Emergência , Hospitalização , Humanos , Medicare , Insuficiência Renal Crônica/epidemiologia , Insuficiência Renal Crônica/terapia , SARS-CoV-2 , Estados Unidos
19.
Br J Dermatol ; 184(6): 1132-1142, 2021 06.
Artigo em Inglês | MEDLINE | ID: mdl-33152110

RESUMO

BACKGROUND: The absence of melanocytes poses a challenge for long-term tissue homeostasis in vitiligo. Surprisingly, while individuals with Fitzpatrick phototypes I-II (low melanin content) have a higher incidence of melanoma and nonmelanoma skin cancer, people with vitiligo are at a decreased risk for the same. OBJECTIVES: To understand the molecular mechanisms that protect vitiligo skin from ultraviolet (UV)-induced DNA damage by (i) characterizing differentially expressed microRNAs in lesional vs. nonlesional epidermis and (ii) identifying their upstream regulators and downstream gene targets. METHODS: Genome-wide microRNA profiling of nonlesional and lesional epidermis was performed on five individuals with stable nonsegmental vitiligo using next-generation RNA sequencing. The relevance of the upstream regulator and downstream target gene of the most differentially expressed microRNA was studied. RESULTS: Our study found sirtuin1 (SIRT1), an NAD-dependent deacetylase, to be a direct target of miR-211 - the most significantly downregulated microRNA in lesional epidermis. Inhibition of SIRT1 with EX-527 downregulated keratin 10 and involucrin, suggesting that SIRT1 promotes keratinocyte differentiation. Overexpression of miR-211 mimic led to a significant increase in γ-H2AX positivity and cyclobutane pyrimidine dimer (CPD) formation, hallmarks of UVB-mediated DNA damage. These effects could be ameliorated by the addition of resveratrol, a SIRT1 activator. Furthermore, a long noncoding RNA, MALAT1, was identified as a negative upstream regulator of miR-211. Overexpression of MALAT1 resulted in increased expression of SIRT1 and a concomitant removal of UVB-induced CPDs in primary keratinocytes. CONCLUSIONS: These findings establish a novel MALAT1-miR-211-SIRT1 signalling axis that potentially confers protection to the 'amelanotic' keratinocytes in vitiligo.


Assuntos
Dano ao DNA , MicroRNAs , RNA Longo não Codificante , Sirtuína 1 , Raios Ultravioleta/efeitos adversos , Vitiligo , Epiderme , Humanos , MicroRNAs/genética , RNA Longo não Codificante/genética , Sirtuína 1/genética , Vitiligo/genética
20.
J Microsc ; 281(3): 224-230, 2021 03.
Artigo em Inglês | MEDLINE | ID: mdl-33020917

RESUMO

The x-z cross-sectional profiles of fluorescent objects can be distorted in confocal microscopy, in large part due to mismatch between the refractive index of the immersion medium of typical high numerical aperture objectives and the refractive index of the medium in which the sample is present. Here, we introduce a method to mount fluorescent samples parallel to the optical axis. This mounting allows direct imaging of what would normally be an x-z cross-section of the object, in the x-y plane of the microscope. With this approach, the x-y cross-sections of fluorescent beads were seen to have significantly lower shape-distortions as compared to x-z cross-sections reconstructed from confocal z-stacks. We further tested the method for imaging of nuclear and cellular heights in cultured cells, and found that they are significantly flatter than previously reported. This approach allows improved imaging of the x-z cross-section of fluorescent samples. LAY DESCRIPTION: Optical distortions are common in confocal microscopy. In particular, the mismatch between the refractive index of the immersion medium of the microscope objective and the refractive index of the sample medium distorts the shapes of fluorescent objects in the x-z plane of the microscope. Here, we introduced a method to eliminate the shape-distortion in the x-z cross-sections. This was achieved by mounting fluorescent samples on vertical glass slides such that the cross-sections orthogonal to the glass surface could be imaged in the x-y plane of the microscope. Our method successfully improved the imaging of nuclear and cellular heights in cultured cells and revealed that the heights were significantly flatter than previously reported with conventional approaches.


Assuntos
Corantes Fluorescentes , Refratometria , Vidro , Microscopia Confocal
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