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1.
Cureus ; 15(9): e45260, 2023 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-37846260

RESUMO

Background Atrial septal defect (ASD) closure with significant left-to-right shunt and concurrent comorbidities poses challenges for intervention. A fenestrated atrial septal defect (FASD) device is a viable option for patients who cannot undergo complete occlusion due to hemodynamic and medical reasons. This study explores the use of FASD occluders in patients with secundum ASD and associated comorbidities where complete occlusion is difficult. Methodology This retrospective study collected the details of patients recommended for FASD closure diagnosed with significant secundum ASD and who had additional comorbidities between July 2015 and July 2023 in a tertiary cardiac center in eastern India. Among this cohort, patients who underwent FASD device placement were subjected to a comprehensive analysis. Results In total, 16 patients diagnosed with secundum ASD, characterized by significant left-to-right shunt and concurrent comorbidities, were considered for FASD closure during the study period. Ultimately, 13 patients (first group) underwent fenestrated atrial septal occluder implantation. The average age was 45.07 years, with the majority being females (n = 9). Comorbidities among this cohort included substantial left ventricular diastolic dysfunction (n = 7), left ventricular diastolic dysfunction coupled with moderate pulmonary hypertension (n = 1), severe pulmonary hypertension (n = 1), severe pulmonary valvular stenosis with right ventricular diastolic dysfunction (n = 2), and systemic lupus erythematosus (SLE) (n = 2). From this cohort, three patients did not undergo the intervention. The second group consisted of an elderly patient with severe left ventricular diastolic dysfunction, a young adult with a history of left atrial arrhythmia, and a child with Duchenne muscular dystrophy (DMD). The average ASD size among patients who underwent the intervention was 26.38 mm, with a thick-to-thick dimension measuring 31.15 mm. The procedure was successful in all 13 patients, with the most frequently used device being a 34 mm occluder (range = 28-40 mm). All devices, excluding the initial one, were custom-made atrial septal occluders (Lifetech Scientific). Among the patients, 12 exhibited left-to-right fenestration flow, while one patient experienced fenestration constriction, likely due to occluder overcrowding. The first patient had a handmade 5 mm fenestration in a 40 mm Amplatzer septal occluder, which got closed off at the one-year follow-up. The procedure was well-tolerated hemodynamically in all patients, with no major complications during the peri-procedural period. Short-term follow-up indicated favorable patient progress. Conclusions FASD closure emerges as a pivotal alternative for intricate scenarios involving secundum ASD coupled with concurrent comorbidities, offering individualized tailored solutions. Alongside the conventional associated comorbidities, such as left ventricular diastolic dysfunction and pulmonary hypertension, FASD devices hold the potential to extend their benefits to patients grappling with other complexities, including severe pulmonary valvular stenosis, SLE, predisposition to left atrial arrhythmia, and conditions like DMD. Ensuring meticulous evaluation of patient suitability and providing ongoing vigilant care becomes paramount for achieving optimal outcomes. The validation of these findings and the broadening of the comprehension of this approach necessitate further comprehensive investigations.

2.
Acta Crystallogr B Struct Sci Cryst Eng Mater ; 79(Pt 2): 148-156, 2023 Apr 01.
Artigo em Inglês | MEDLINE | ID: mdl-36920873

RESUMO

Amongst the derivatives of 4-biphenylcarboxylic acid and amino acid esters, the crystal structure of 4-biphenylcarboxy-(L)-phenylalaninate is unusual owing to its monoclinic symmetry within a pseudo-orthorhombic crystal system. The distortion is described by a disparate rotational property around the chiral centers (ϕchiral ≃ -129° and 58°) of the two molecules in the asymmetric unit. Each of these molecules comprises planar biphenyl moieties (ϕbiphenyl = 0°). Using temperature-dependent single-crystal X-ray diffraction experiments we show that the compound undergoes a phase transition below T ∼ 124 K that is characterized by a commensurate modulation wavevector, q = δ(101), δ = ½. The (3+1)-dimensional modulated structure at T = 100 K suggests that the phase transition drives the biphenyl moieties towards noncoplanar conformations with significant variation of internal torsion angle (ϕmaxbiphenyl ≤ 20°). These intramolecular rotations lead to dimerization of the molecular stacks that are described predominantly by distortions in intermolecular tilts (θmax ≤ 20°) and small variations in intermolecular distances (Δdmax ≃ 0.05 Å) between biphenyl molecules. Atypical of modulated structures and superstructures of biphenyl and other polyphenyls, the rotations of individual molecules are asymmetric (Δϕbiphenyl ≈ 5°) while ϕbiphenyl of one independent molecule is two to four times larger than the other. Crystal-chemical analysis and phase relations in superspace suggest multiple competing factors involving intramolecular steric factors, intermolecular H-C...C-H contacts and weak C-H...O hydrogen bonds that govern the distinctively unequal torsional properties of the molecules.

3.
Cureus ; 14(2): e22480, 2022 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-35223335

RESUMO

Objective Transcatheter atrial septal defect (ASD) device closure in the older population presents a greater challenge due to the long-standing effect of atrial left-to-right shunt. This study analyzes the challenges encountered in transcatheter ASD device closure in older patients in their fifth decade and beyond. Methods Adults aged 40 years and above with significant secundum ASD who underwent transcatheter ASD device closure between June 2015 and April 2021 were analyzed. Challenges were classified as major and minor challenges based on their impact on the alteration of the treatment protocol. Patients were categorized into three subgroups according to age. Group 1 consisted of patients aged 40-49 years (n = 13), Group 2 consisted of patients aged 50-59 years (n = 16), and Group 3 consisted of patients aged 60 years and above (n = 8). Results A total of 37 patients were analyzed. The challenges encountered were arrhythmia, pulmonary hypertension, left ventricular diastolic dysfunction, bleeding, stroke, coronary artery disease (CAD), hypertension, and airway disease. Thirteen percent of challenges were seen in pre-procedure time, whereas 79% of challenges during the procedure and 8% of challenges during post-procedure were seen. Thirty-five patients (94.6%) underwent transcatheter ASD device closure. Two patients (5.4%) did not undergo transcatheter ASD device closure due to severe diastolic dysfunction and associated CAD, respectively. Eleven major challenges were encountered in 10 patients in which one patient had a dual challenge of bleeding and arrhythmia. Thirteen patients (35.1%) had smooth procedures without any challenges encountered. Twenty-seven minor challenges were encountered in 20 patients with some patients having an overlap of multiple major and minor challenges. The patients were doing well at the mean follow-up of 28 months. Conclusions Transcatheter ASD device closure in older patients who are 40 years and above is safe and effective. Such high-risk patients are prone to various challenges that can be effectively managed if optimally monitored on the basis of a proper understanding of the altered physiology and anticipation of the deviated course at various stages of the procedure.

4.
Chemistry ; 28(13): e202104151, 2022 Mar 01.
Artigo em Inglês | MEDLINE | ID: mdl-35072296

RESUMO

Phase transitions in molecular crystals are often determined by intermolecular interactions. The cage complex of [Co(C12 H30 N8 )]3+ ⋅ 3 NO3 - is reported to undergo a disorder-order phase transition at Tc1 ≈133 K upon cooling. Temperature-dependent neutron and synchrotron diffraction experiments revealed satellite reflections in addition to main reflections in the diffraction patterns below Tc1 . The modulation wave vector varies as function of temperature and locks in at Tc3 ≈98 K. Here, we demonstrate that the crystal symmetry lowers from hexagonal to monoclinic in the incommensurately modulated phases in Tc1

5.
Am J Cardiovasc Dis ; 11(5): 624-627, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34849294

RESUMO

Chronic total occlusion (CTO) of coronary artery is a subset where cardiologists confront technical challenges most of the time during percutaneous coronary intervention (PCI). They experience an additional impediment when CTO intervention is performed in presence of anomalous coronary artery. Here we report a 58 years old gentleman with Diabetes mellitus and hypertension who admitted with Canadian Cardiovascular Society class III angina for 5 months. Coronary angiography revealed dual vessel coronary artery disease with CTO of right coronary artery (RCA) originating from left sinus of Valsalva. PCI with stenting has been done successfully to RCA lesion. Patient got relieved of angina after PCI and remains stable clinically since then.

7.
ACS Appl Mater Interfaces ; 13(34): 41094-41101, 2021 Sep 01.
Artigo em Inglês | MEDLINE | ID: mdl-34410686

RESUMO

Novel methods to synthesize electron-deficient π-conjugated polymers utilizing transition-metal-free coupling reactions for the use of nonfunctionalized monomers are attractive due to their improved atom economy and environmental prospective. Herein we describe the use of iPrMgCl·LiCl complex to afford thiazole-based conjugated polymers in the absence of any transition metal catalyst, that enables access to well-defined polymers with good molecular weights. The mechanistically distinct polymerizations proceeded via nucleophilic aromatic substitution (SNAr) reaction supported by density functional theory (DFT) calculations. This work demonstrates the first example of fully conjugated thiazole-based aromatic homopolymers without the need of any transition metal catalyst.

8.
Science ; 373(6552): 321-327, 2021 07 16.
Artigo em Inglês | MEDLINE | ID: mdl-34437150

RESUMO

Living tissue uses stress-accumulated electrical charge to close wounds. Self-repairing synthetic materials, which are typically soft and amorphous, usually require external stimuli, prolonged physical contact, and long healing times. We overcome many of these limitations in piezoelectric bipyrazole organic crystals, which recombine following mechanical fracture without any external direction, autonomously self-healing in milliseconds with crystallographic precision. Kelvin probe force microscopy, birefringence experiments, and atomic-resolution structural studies reveal that these noncentrosymmetric crystals, with a combination of hydrogen bonds and dispersive interactions, develop large stress-induced opposite electrical charges on fracture surfaces, prompting an electrostatically driven precise recombination of the pieces via diffusionless self-healing.

9.
Indian Heart J ; 73(3): 264-272, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34154741

RESUMO

There is mounting evidence which suggests the involvement of gut microbiota dysbiosis in the pathogenesis of various cardiovascular diseases (CVD) and associated risk states such as hypertension, type 2 diabetes, obesity and dyslipidaemia, atherosclerosis, heart failure and atrial fibrillation. The current review comprehensively summarizes the various pathogenetic mechanisms of dysbiosis in these conditions and discusses the key therapeutic implications. Further deeper understanding of the pathogenetic links between CVD and gut microbiota dysbiosis can aid in the development of novel microbiota-based targets for the management of CVDs.


Assuntos
Doenças Cardiovasculares , Microbioma Gastrointestinal , Doenças Cardiovasculares/etiologia , Diabetes Mellitus Tipo 2 , Disbiose , Humanos , Hipertensão
10.
Org Biomol Chem ; 19(23): 5114-5120, 2021 Jun 16.
Artigo em Inglês | MEDLINE | ID: mdl-34018542

RESUMO

Herein we report the synthesis, characterization and application of an azaheterocycle 4 obtained via an unprecedented C-N coupling. The neutral azaheterocycle undergoes one-electron reduction to form an air-stable radical anion in situ, which provides added benefit towards operational stability of the device during n-type charge transport. The unusual stability of this radical anion is due to the fact that the fused cyclopentane ring upon reduction forms aromatic cyclopentadienyl anion, and the negative charge delocalizes over the nearly planar azaheterocycle core. The present azaheterocycle can be considered as a mimic of a fullerene fragment, which shows balanced ambipolar charge transport in space charge limited current (SCLC) devices with moderate hole (µh) and electron (µe) mobilities (µh = 2.96 × 10-3 cm2 V-1 s-1 and µe = 1.11 × 10-4 cm2 V-1 s-1). Theoretical studies such as nucleus independent chemical shifts (NICS) calculations, anisotropy of the induced current density (ACID) plots, spin density mapping and anisotropic mobility calculations were performed to corroborate the experimental findings.

11.
Am J Cardiovasc Dis ; 11(6): 710-713, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-35116183

RESUMO

Symptomatic bradycardia attributed by sick sinus syndrome in hypertrophic cardiomyopathy (HCM) is not commonly seen. Dual chamber pacing with right ventricular apical lead placement is conventional strategy in such scenario. Now physiological pacing which includes left bundle branch (LBB) pacing emerging as new technology for pacemaker implantation. Use of this technique is difficult in HCM due to septal hypertrophy. There is no such case reported so far in the literature where LBB pacing was performed in adult HCM for sick sinus syndrome. Here we present a novel approach of treating irreversible, symptomatic sinus node dysfunction in non-obstructive HCM with implementation of left bundle pacing strategy. Pacing parameters remain stable after 3 months of follow-up.

12.
Inorg Chem ; 59(18): 13295-13300, 2020 Sep 21.
Artigo em Inglês | MEDLINE | ID: mdl-32881492

RESUMO

A single crystal of the boron subhydride B104.67(4)H3 was serendipitously obtained while attempting to synthesize ß-boron. An accurate crystal structure analysis revealed a distorted ß-boron framework with the noncentrosymmetric space group R3m. We have found one interstitial site occupied by boron. The site related by inversion remains empty. The distortions of the framework result in ideal environments for the interstitial boron atom, and for the three hydrogen atoms at bridging positions between icosahedral B12 groups, they result in ideal B-H distances of 1.33 Å. B104.67(4)H3 is a borane with the lowest amount of hydrogen recorded to date, and it is the first compound with a noncentrosymmetrically distorted ß-boron framework.

13.
Am J Cardiovasc Dis ; 10(3): 182-188, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32923099

RESUMO

BACKGROUND: The ultrathin strut stents (<60 µm) are new in the current stents technology. This technology has assured to have less stent thrombosis, restenosis and better deliverability. Still there is lacking data of using long ultrathin strut stents in very long segment coronary artery disease (>30 mm). AIM: The aim of this retrospective study was to assess the procedural safety and outcome of using ultrathin strut stents in very long segment coronary artery lesion. METHODS: In this retrospective analysis, we have enrolled those patients who had an implant of more than 30 mm length of ultrathin strut stents (Evermine 50TM and Tetrilimus stents) in real world patients as per physician discretion. Here, we enrolled 156 patients which included both acute coronary syndrome (ACS) and stable ischemic heart disease (SIHD). The endpoint of this study was to evaluate the immediate procedural success and short to intermediate term follow-up of all-cause mortality and clinically driven target lesion revascularization. RESULTS: Out of these 156 patients (mean age- 61.2 +/- 10.4 years; male: 114), in 12 patients, these long stents couldn't be delivered. In rest 144 patients, 147 ultrathin strut stents were implanted. In about 56% patients were hypertensive and 48% patients were diabetic. About 63% patients had ACS and rest 37% patients had SIHD. The mean duration of follow up was 8.4 +/- 13.9 months. Average stent length and diameter were 39.5 +/- 5.9 mm and 3.03 +/- 0.4 mm, respectively. There was no acute or sub-acute stent thrombosis and no procedural complication. Five patients died during follow-up (all-cause mortality) and rest are all symptoms free. There were no statistical significant differences seen among the stent types. CONCLUSION: Ultrathin strut stents can be considered for stenting in long segment coronary artery stenosis with reasonably good procedural success rate and have good clinical outcome, but needs further large randomized trial before using in this particular clinical condition. Both the stent designs have similar clinical outcome and procedural success.

14.
Am J Cardiovasc Dis ; 10(2): 117-123, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32685269

RESUMO

BACKGROUND: Clinical trials that evaluated long-term clinical outcomes of thrombus aspiration before primary percutaneous coronary intervention (PCI) in patients with ST-segment elevation myocardial infarction (STEMI) have shown different results. Thus, this study was designed to evaluate the long-term clinical outcomes and trends in present usage of thrombosuction in STEMI patients undergoing primary PCI. METHODS: This was a single-center, retrospective study conducted at a tertiary-care center in India between January 2016 and December 2018. A total of 241 patients with STEMI who underwent primary PCI were differentiated into thrombus aspiration or standard primary PCI group. Primary endpoint was major adverse cardiac events (MACE) at 1-year. The other safety outcome measured at 1-year follow-up was stent thrombosis. RESULTS: Among 241 patients, 119 patients were included in the thrombus aspiration group and 122 patients were included in the standard primary PCI group. All patients underwent 1-year follow-up. MACE rate was found to be 4.2% and 4.9% in thrombus aspiration and standard primary PCI group (P=0.79), respectively. Death from any cause was found to be higher in thrombus aspiration 7 (5.9%) compared to standard primary PCI group 5 (4.1%). Of which, cardiac death has occurred in 5 (4.2%) patients of thrombus aspiration group and 4 (3.3%) patients of standard primary PCI group (P=0.747). Definite stent thrombosis was observed in 1 (0.8%) patient of both the groups (P=1.00). CONCLUSION: The study concludes that there was no significant benefit of thrombus aspiration concerning mortality rate or any other clinical outcomes at 1-year in STEMI patients.

15.
Angew Chem Int Ed Engl ; 59(45): 19878-19883, 2020 11 02.
Artigo em Inglês | MEDLINE | ID: mdl-32667123

RESUMO

Single crystals of optoelectronic materials that respond to external stimuli, such as mechanical, light, or heat, are immensely attractive for next generation smart materials. Here we report single crystals of a green fluorescent protein (GFP) chromophore analogue with irreversible mechanical bending and associated unusual enhancement of the fluorescence, which is attributed to the strained molecular packing in the perturbed region. Soft crystalline materials with such fluorescence intensity modulations occurring in response to mechanical stimuli under ambient pressure conditions will have potential implications for the design of technologically relevant tunable fluorescent materials.

16.
Angew Chem Int Ed Engl ; 59(27): 10971-10980, 2020 Jun 26.
Artigo em Inglês | MEDLINE | ID: mdl-32087039

RESUMO

Ductility is a common phenomenon in many metals but is difficult to achieve in molecular crystals. Organic crystals bend plastically on one or two face-specific directions but fracture when stressed in any other arbitrary directions. An exceptional metal-like ductility and malleability in the isomorphous crystals of two globular molecules, BH3 NMe3 and BF3 NMe3 , is reported, with characteristic tensile stretching, compression, twisting, and thinning. The mechanically deformed samples, which transition to lower symmetry phases, retain good long-range order amenable to structure determination by single-crystal X-ray diffraction. Molecules in these high-symmetry crystals interact through electrostatic forces (B- -N+ ) to form columnar structures with multiple slip planes and weak dispersive forces between columns. On the other hand, the limited number of facile slip planes and strong dihydrogen bonding in BH3 NHMe2 negates ductility. Our study has implications for the design of soft ferroelectrics, solid electrolytes, barocalorics, and soft robotics.

17.
Nat Commun ; 10(1): 3711, 2019 08 16.
Artigo em Inglês | MEDLINE | ID: mdl-31420538

RESUMO

Molecular crystals are not known to be as stiff as metals, composites and ceramics. Here we report an exceptional mechanical stiffness and high hardness in a known elastically bendable organic cocrystal [caffeine (CAF), 4-chloro-3-nitrobenzoic acid (CNB) and methanol (1:1:1)] which is comparable to certain low-density metals. Spatially resolved atomic level studies reveal that the mechanically interlocked weak hydrogen bond networks which are separated by dispersive interactions give rise to these mechanical properties. Upon bending, the crystals significantly conserve the overall energy by efficient redistribution of stress while perturbations in hydrogen bonds are compensated by strengthened π-stacking. Furthermore we report a remarkable stiffening and hardening in the elastically bent crystal. Hence, mechanically interlocked architectures provide an unexplored route to reach new mechanical limits and adaptability in organic crystals. This proof of concept inspires the design of light-weight, stiff crystalline organics with potential to rival certain inorganics, which currently seem inconceivable.

18.
Small ; 15(21): e1900134, 2019 May.
Artigo em Inglês | MEDLINE | ID: mdl-30989808

RESUMO

The quest for sustainable energy sources has led to accelerated growth in research of organic solar cells (OSCs). A solution-processed bulk-heterojunction (BHJ) OSC generally contains a donor and expensive fullerene acceptors (FAs). The last 20 years have been devoted by the OSC community to developing donor materials, specifically low bandgap polymers, to complement FAs in BHJs. The current improvement from ≈2.5% in 2013 to 17.3% in 2018 in OSC performance is primarily credited to novel nonfullerene acceptors (NFA), especially fused ring electron acceptors (FREAs). FREAs offer unique advantages over FAs, like broad absorption of solar radiation, and they can be extensively chemically manipulated to tune optoelectronic and morphological properties. Herein, the current status in FREA-based OSCs is summarized, such as design strategies for both wide and narrow bandgap FREAs for BHJ, all-small-molecule OSCs, semi-transparent OSC, ternary, and tandem solar cells. The photovoltaics parameters for FREAs are summarized and discussed. The focus is on the various FREA structures and their role in optical and morphological tuning. Besides, the advantages and drawbacks of both FAs and NFAs are discussed. Finally, an outlook in the field of FREA-OSCs for future material design and challenges ahead is provided.

19.
J Oral Biol Craniofac Res ; 6(3): 179-186, 2016.
Artigo em Inglês | MEDLINE | ID: mdl-27761381

RESUMO

BACKGROUND: Head and neck cancer in Indian perspective predominantly relates to tobacco use. The present study explores the prevalence of oral ulcers and its association with addictions among the population of Uttar Pradesh and Rajasthan, India. METHODOLOGY: The screening method in early detection of head and neck cancer is broadly symptom based. 1399 subjects from Uttar Pradesh and Rajasthan were screened by trained personnel between April and June 2015. RESULTS: Study findings showed, mouth ulcers and trismus were common symptoms and tobacco chewing and smoking were common addictions. There were statistically significant associations among the symptoms and addictions as well as predominance in rural populations. The majority of smokers (27.1%) belonged to age ≥55 years whereas the tobacco chewers (29.2%) and alcohol abusers (45.8%) in the age group 25-34 years. Also the risk of developing mouth ulcers and trismus in this area are approximately 35 (MRR: 35.7, 95% CI: 15.5-81.9) and nearly eight (MRR: 7.7, 95% CI: 2.2-26.6) times higher respectively in males. However, joint use of smoked and smokeless tobacco increases nearly three times more risk of either mouth ulcers or trismus. CONCLUSION: Male individuals are more exposed to certain addictions such as tobacco (smoked and smokeless) and alcohol. The prevalence of oral ulcers is primarily associated with the addictions. Therefore, these persons are more at risk of further developing head neck cancer. A large level community screening and awareness are required especially among the rural population of India.

20.
Acta Crystallogr B Struct Sci Cryst Eng Mater ; 72(Pt 3): 372-80, 2016 06 01.
Artigo em Inglês | MEDLINE | ID: mdl-27240768

RESUMO

Λ-Cobalt(III) sepulchrate trinitrate crystallizes in P6322 with Z = 2 (Z' = 1/6) at room temperature. Slabs perpendicular to the hexagonal axis comprise molecules Co(sepulchrate) alternating with nitrate groups A and B. Coordinated by six sepulchrate molecules, highly disordered nitrate groups C are accommodated between the slabs. Here we report the fully ordered, low-temperature crystal structure of Co(sep)(NO3)3. It is found to be a high-Z' structure with Z' = 12 of the 12-fold 6a_{h}\times\sqrt{3}b_{h}\times c_{h} superstructure with monoclinic symmetry P21 (c unique). Correlations between structural parameters are effectively removed by refinements within the superspace approach. Superstructure formation is governed by a densification of the packing in conjunction with ordering of nitrate group C, the latter assuming different orientations for each of the Z' = 12 independent copies in the superstructure. The Co(sep) moiety exhibits small structural variations over its 12 independent copies, while orientations of nitrate groups A and B vary less than the orientations of the nitrate group C do. Molecular packing in the superstructure is found to be determined by short C-H...H-C contacts, with H...H distances of 2.2-2.3 Å, and by short C-H...O contacts, with H...O distances down to 2.2 Å. These contacts presumably represent weak C-H...O hydrogen bonds, but in any case they prevent further densification of the structure and strengthening of weak N-H...O hydrogen bonds with observed H...O distances of 2.4-2.6 Å.

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