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1.
Trends Genet ; 38(4): 307-309, 2022 04.
Artigo em Inglês | MEDLINE | ID: mdl-35135699

RESUMO

Modern wheat shows phenomenal evolutional success and adaptability to a range of environments owing to polyploidization; however, during its hybridization process a major genetic gain has been overlooked. Recently, Gaurav et al. emphasized harnessing genetic diversity from wheat wild progenitor Aegilops tauschii for the improvement of hexaploid wheat through introgression or transgenesis.


Assuntos
Aegilops , Aegilops/genética , Triticum/genética
2.
Mol Biol Rep ; 51(1): 537, 2024 Apr 20.
Artigo em Inglês | MEDLINE | ID: mdl-38642174

RESUMO

BACKGROUND: Hexaploid bread wheat underwent a series of polyploidization events through interspecific hybridizations that conferred adaptive plasticity and resulted in duplication and neofunctionalization of major agronomic genes. The genetic architecture of polyploid wheat not only confers adaptive plasticity but also offers huge genetic diversity. However, the contribution of different gene copies (homeologs) encoded from different subgenomes (A, B, D) at different growth stages remained unexplored. METHODS: In this study, hybrid of elite cultivars of wheat were developed via reciprocal crosses (cytoplasm swapping) and phenotypically evaluated. We assessed differential expression profiles of yield-related negative regulators in these cultivars and their F1 hybrids and identified various cis-regulatory signatures by employing bioinformatics tools. Furthermore, the preferential expression patterns of the syntenic triads encoded from A, B, and D subgenomes were assessed to decipher their functional redundancy at six different growth stages. RESULTS: Hybrid progenies showed better heterosis such as up to 17% increase in the average number of grains and up to 50% increase in average thousand grains weight as compared to mid-parents. Based on the expression profiling, our results indicated significant dynamic transcriptional expression patterns, portraying the different homeolog-dominance at the same stage in the different cultivars and their hybrids. Albeit belonging to same syntenic triads, a dynamic trend was observed in the regulatory signatures of these genes that might be influencing their expression profiles. CONCLUSION: These findings can substantially contribute and provide insights for the selective introduction of better cultivars into traditional and hybrid breeding programs which can be harnessed for the improvement of future wheat.


Assuntos
Melhoramento Vegetal , Triticum , Triticum/genética , Hibridização Genética , Vigor Híbrido/genética
3.
Br J Neurosurg ; : 1-5, 2024 Apr 26.
Artigo em Inglês | MEDLINE | ID: mdl-38712620

RESUMO

PURPOSE: Degenerative cervical myelopathy (DCM) is the commonest cause of adult spinal cord dysfunction worldwide, for which surgery is the mainstay of treatment. At present, there is limited literature on the costs associated with the surgical management of DCM, and none from the United Kingdom (UK). This study aimed to evaluate the cost-effectiveness of DCM surgery within the National Health Service, UK. MATERIALS AND METHODS: Incidence of DCM was identified from the Hospital Episode Statistics (HES) database for a single year using five ICD-10 diagnostic codes to represent DCM. Health Resource Group (HRG) data was used to estimate the mean incremental surgery (treatment) costs compared to non-surgical care, and the incremental effect (quality adjusted life year (QALY) gain) was based on data from a previous study. A cost per QALY value of <£30,000/QALY (GBP) was considered acceptable and cost-effective, as per the National Institute for Health and Clinical Excellence (NICE) guidance. A sensitivity analysis was undertaken (±5%, ±10% and ±20%) to account for variance in both the cost of admission and QALY gain. RESULTS: The total number of admissions for DCM in 2018 was 4,218. Mean age was 62 years, with 54% of admissions being of working age (18-65 years). The overall estimated cost of admissions for DCM was £38,871,534 for the year. The mean incremental (per patient) cost of surgical management of DCM was estimated to be £9,216 (ranged £2,358 to £9,304), with a QALY gain of 0.64, giving an estimated cost per QALY value of £14,399/QALY. Varying the QALY gain by ±20%, resulted in cost/QALY figures between £12,000 (+20%) and £17,999 (-20%). CONCLUSIONS: Surgery is estimated to be a cost-effective treatment of DCM amongst the UK population.

4.
Saudi Pharm J ; 32(1): 101898, 2024 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-38192384

RESUMO

Dodonaea viscosa grows widely in Saudi Arabia, but studies evaluating its neuroprotective activity are lacking. Thus, this study aimed to isolate and identify the secondary metabolites and evaluate the neuroprotective effects of D. viscosa leaves. The isolation and identification of phytochemicals were performed using chromatographic and spectroscopic techniques. The neuroprotective potential of the extract was evaluated against focal cerebral ischaemia-reperfusion injury in rat model. Neurobehavioural deficits in the rats were evaluated, and their brains were harvested to measure infarct volume and oxidative biomarkers. Results revealed the presence of three compounds: a novel isoprenylated phenolic derivative that was elucidated as 4-hydroxy-3-(3'-methyl-2'-butenyl) phenyl 1-O-ß-D-apiosyl-(1''' â†’ 6'')- ß-D-glucopyranoside (named Viscomarfadol) and two known compounds (isorhamnetin-3-O-rutinoside and epicatechin (4-8) catechin). Pre-treatment of the rats with the extract improved neurological outcomes. It significantly reduced neurological deficits and infarct volume; significantly reduced lipid peroxidation, as evidenced by decreased malondialdehyde levels; and significantly elevated antioxidant (superoxide dismutase, catalase, and glutathione) activities. These results indicate that D. viscosa is a promising source of bioactive compounds that can improve neurological status, decrease infarct volume, and enhance antioxidant activities in rats with cerebral ischaemic injury. Thus, D. viscosa could be developed into an adjuvant therapy for ischaemic stroke and other oxidative stress-related neurodegenerative disorders. Further investigations are warranted to explore other bioactive compounds in D. viscosa and evaluate their potential neuroprotective activities.

5.
Eur Spine J ; 32(1): 38-45, 2023 01.
Artigo em Inglês | MEDLINE | ID: mdl-36469131

RESUMO

BACKGROUND: Osteoporotic vertebral compression fractures (OVCF) are common in elderly patients and may cause local kyphosis due to the vertebral collapse and wedging. Balloon kyphoplasty (BKP) with polymethyl methacrylate is widely used to relieve back pain and restore the height and kyphosis of the destroyed vertebra Johnell (Osteoporos Int 17(12):1726-33, 2006); Wasnich (Bone 18: 179S-183S, 1996); Finnern (Osteoporos Int 14:429-436, 2003). However, the influence of BKP on global sagittal alignment (GSA) in patients with OVCF remains unclear. OBJECTIVE: To systematically evaluate the relevant literature regarding the influence of BKP on the global spinal sagittal alignment using the following radiological parameters: Pelvic Incidence (PI), Pelvic Tilt (PT), Lumbar Lordosis (LL), Thoracic Kyphosis (TK), Sagittal Vertical Axis (SVA) and Spinosacral Angle (SSA). Visual Analogue Score (VAS) was also recorded. METHODS: A systematic review of the English language literature dating up until August 2022, was undertaken utilising the PRISMA guidelines. RESULTS: Of a total of 548 articles, 4 studies met the inclusion criteria (4 level III evidence) and were analyzed. Overall, 201 patients of mean age 73.8 years (69-77) had acute OVCF of one or more vertebra. The male to female ratio was 51:128. The number of fractured vertebrae was 235 (average of 1.17 fractured vertebrae per patient). Their pre-operative radiological parameters on standing x-rays showed a mean PI of 56°, PT 24.1°, LL 44.4°, TK 42.3°, PI-LL 11.7°, SVA 4.9 cm, LL/TK 1 and SSA 114.8°. The average VAS was 7.6 (2.6-10). All the patients underwent BKP and their radiological parameters on standing x-rays post operatively showed a mean PI of 55.3°, PT 23.1°, LL 45.1°, TK 41.4°, PI-LL 10.3°, SVA 4.29 cm, LL/TK 1.07 and SSA 116.8°. Their average VAS post BPK was 2.36 (0-4.8).A statistical analysis comparing the pre/post-operative GSA (111 patients, 3 studies with standard deviations) showed no statistical difference in PT (24.1° vs. 23.5°, P = 0.93), TK (42.3° vs. 42.4°, P = 0.57), PI-LL (14.4° vs.12.4°, P = 0.4), SVA (6.1 cm vs. 5.5 cm, P = 0.19) SSA (114.8° vs. 116.7° P = 0.36). VAS was significantly reduced post BKP (7.1 vs. 2.5 P = 0.004). CONCLUSION: Performing BKP procedures does not significantly affect the global sagittal alignment in patients with osteoporotic vertebral compression fractures. There was however, a significant improvement in pain scores in patients undergoing BKP at 1 or more levels.


Assuntos
Doenças Ósseas Metabólicas , Fraturas por Compressão , Cifoplastia , Cifose , Lordose , Fraturas por Osteoporose , Fraturas da Coluna Vertebral , Humanos , Masculino , Feminino , Idoso , Fraturas por Compressão/diagnóstico por imagem , Fraturas por Compressão/cirurgia , Fraturas da Coluna Vertebral/diagnóstico por imagem , Fraturas da Coluna Vertebral/cirurgia , Fraturas da Coluna Vertebral/complicações , Cifoplastia/métodos , Coluna Vertebral/cirurgia , Cifose/diagnóstico por imagem , Cifose/cirurgia , Cifose/etiologia , Lordose/complicações , Fraturas por Osteoporose/diagnóstico por imagem , Fraturas por Osteoporose/cirurgia , Doenças Ósseas Metabólicas/complicações , Vértebras Lombares/diagnóstico por imagem , Vértebras Lombares/cirurgia , Vértebras Lombares/lesões , Estudos Retrospectivos
6.
Eur Spine J ; 32(1): 1-7, 2023 01.
Artigo em Inglês | MEDLINE | ID: mdl-36163394

RESUMO

BACKGROUND: Despite the heterogeneity of chronic lower back pain aetiologies, cluneal nerve entrapment remains underdiagnosed and poorly understood with few studies discussing the efficacy of its surgical release. OBJECTIVE: The current study opts to conduct a systematic review reporting on the efficacy of cluneal nerve surgical decompression in patients with an established diagnosis who fail conservative treatment. We aimed to systematically evaluate the literature regarding the clinical outcomes, recurrence of symptoms and revision rates of surgical intervention. METHODS: A systematic review of the English language literature dating up until May 2022 was undertaken according to the PRISMA guidelines. Isolated case reports were excluded. RESULTS: Of a total of 54 articles, 4 studies met the inclusion criteria (three were level IV evidence and one level III evidence) and were analyzed. Overall, 98 patients of mean age 61 years, (range 17-86) underwent cluneal nerve release with a mean follow-up of 25.5 months (6-58 months). There was significant improvement in symptoms post operatively in the 4 studies. No systemic or local complications were encountered during the surgeries. Four articles reported on revision surgery for recurrent symptoms in 8 patients out of 98 with a rate of 8.2%. Of the reoperated patients, 7/8 had new branches released that were not addressed initially and 1 had neurectomy for an adhered pre-released branch. CONCLUSION: This systematic review demonstrated that cluneal nerve decompression has been performed in a total of 98 patients with significant clinical improvement, zero systemic and local complications and revision rates of 8.2% of the cases.


Assuntos
Dor Lombar , Síndromes de Compressão Nervosa , Humanos , Lactente , Pré-Escolar , Criança , Dor Lombar/cirurgia , Dor Lombar/complicações , Síndromes de Compressão Nervosa/complicações , Nádegas/inervação , Nádegas/cirurgia , Procedimentos Neurocirúrgicos/efeitos adversos , Descompressão Cirúrgica/efeitos adversos
7.
Eur Spine J ; 32(9): 3047-3057, 2023 09.
Artigo em Inglês | MEDLINE | ID: mdl-37306799

RESUMO

BACKGROUND CONTEXT: Whilst spinal fusion remains the gold standard in the treatment of adolescent idiopathic scoliosis (AIS), anterior vertebral body tethering (AVBT) is gaining momentum with relatively few studies on its efficacy thus far. PURPOSE: To conduct a systematic review reporting on the early results of AVBT for patients undergoing surgery for AIS. We aimed to systematically evaluate the relevant literature pertaining to the efficacy of AVBT with respect to degree of correction of the major curve Cobb angle, complications and revision rates. STUDY DESIGN/SETTING: Systematic review. PATIENT SAMPLE: Of a total of 259 articles, 9 studies met the inclusion criteria and were analysed. Overall, 196 patients of (mean age 12.08 years) underwent an AVBT procedure for correction of AIS with a mean follow-up of 34 months. OUTCOME MEASURES: Degree of Cobb angle correction, complications and revision rates were used as outcome measures. METHODS: A systematic review of the literature on AVBT was performed for studies published between Jan 1999-March 2021 applying the PRISMA guidelines. Isolated case reports were excluded. RESULTS: Overall, 196 patients of (mean age 12.08 years) underwent an AVBT procedure for correction of AIS with a mean follow-up of 34 months. There was a significant correction of the main thoracic curve of scoliosis (mean preoperative Cobb angle 48.5°, post-operative Cobb angle at final follow-up of 20.1°, P = 0.01). Overcorrection and mechanical complications were seen in 14.3% and 27.5% of cases, respectively. Pulmonary complications including atelectasis and pleural effusion were seen in 9.7% of patients. Tether revision was performed in 7.85%, and revision to a spinal fusion in 7.88%. CONCLUSION: This systematic review incorporated 9 studies of AVBT and 196 patients with AIS. The complication and revision to spinal fusion rates were 27.5% and 7.88%, respectively. The current literature on AVBT is restricted largely to retrospective studies with non-randomised data. We would recommend a prospective, multi-centre trial of AVBT with strict inclusion criteria and standardised outcome measures.


Assuntos
Cifose , Escoliose , Fusão Vertebral , Humanos , Adolescente , Criança , Escoliose/diagnóstico por imagem , Escoliose/cirurgia , Corpo Vertebral , Seguimentos , Estudos Retrospectivos , Estudos Prospectivos , Fusão Vertebral/métodos , Resultado do Tratamento , Vértebras Torácicas/diagnóstico por imagem , Vértebras Torácicas/cirurgia , Estudos Multicêntricos como Assunto
8.
Eur Spine J ; 32(7): 2580-2587, 2023 07.
Artigo em Inglês | MEDLINE | ID: mdl-37222801

RESUMO

BACKGROUND: Thoracic kyphosis, or loss of lumbar lordosis, is often equated with osteoporosis because vertebral fractures are assumed to be a major causative factor, in addition to degeneration related to age. Despite the few studies aiming to measure the natural change in global sagittal alignment (GSA) that occurs with advancing age, the overall effect of conservatively managed osteoporotic vertebral compression fractures (OVCF) on the GSA in the elderly remains poorly understood. OBJECTIVE: To systematically evaluate the relevant literature regarding the influence of OVCF on the GSA compared to patients of similar age without fractures using the following radiological parameters: Pelvic Incidence (PI), Pelvic Tilt (PT), Lumbar Lordosis (LL), Thoracic Kyphosis (TK), Sagittal Vertical Axis (SVA) and Spino-sacral Angle (SSA). METHODS: A systematic review of the English language literature dating up until October 2022, was undertaken utilizing the PRISMA guidelines. RESULTS: Of a total of 947 articles, 10 studies met the inclusion criteria (4 Level II, 4 level III and 2 level IV evidence) and were subsequently analyzed. Overall, 584 patients (8 studies) of mean age 73.7 years (69.3-77.1) had acute OVCF of one or more vertebra that were managed conservatively. The male to female ratio was 82:412. Five studies mentioned the number of fractured vertebrae, with a total of 393 in 269 patients (average of 1.4 fractured vertebrae per patient). Their pre-operative radiological parameters on standing X-rays showed a mean PI of 54.8°, PT 24°, LL 40.8°, TK 36.5°, PI-LL 14°, SVA 4.8 cm, and SSA 115°. In addition, 437 patients were used as a control group with osteoporosis without fractured vertebrae, (6 studies) with an average age of 72.4 years (67-77.8) and male to female ratio of 96:210 (5 studies). They all had upright X-rays to assess their global sagittal alignments. Radiological parameters showed an average PI of 54.3°, PT 17.3°, LL 43.4°, TK 31.25°, PI-LL 10.95°, SVA 1.27 cm and SSA 125°. A statistical analysis comparing the OVCF group with the control group (4 studies), showed a significant increase in PT of 5.97° (95%CI 2.63, 9.32; P < 0.0005), a significant increase in TK by 8.28° (95%CI 2.15, 14.4; P < 0.008), an increase in PI-LL by 6.72° (95%CI 3.39, 10.04; P < 0.0001), an increase in SVA by 1.35 cm (95%CI 0.88, 1.83; P < 0.00001), and a decrease in SSA by 10.2° (95%CI 10.3, 23.4; P < 0.00001). CONCLUSION: Osteoporotic vertebral compression fractures managed conservatively appear to be a significant causate factor of global sagittal imbalance.


Assuntos
Doenças Ósseas Metabólicas , Fraturas por Compressão , Cifose , Lordose , Osteoporose , Fraturas por Osteoporose , Fraturas da Coluna Vertebral , Humanos , Masculino , Feminino , Idoso , Lordose/diagnóstico por imagem , Lordose/complicações , Fraturas por Compressão/diagnóstico por imagem , Fraturas da Coluna Vertebral/diagnóstico por imagem , Fraturas da Coluna Vertebral/terapia , Fraturas da Coluna Vertebral/complicações , Vértebras Lombares/cirurgia , Cifose/cirurgia , Fraturas por Osteoporose/diagnóstico por imagem , Fraturas por Osteoporose/terapia , Osteoporose/complicações , Doenças Ósseas Metabólicas/complicações , Estudos Retrospectivos
9.
An Acad Bras Cienc ; 95(2): e20220680, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37341275

RESUMO

In this study, a hybrid control strategy is proposed to improve the tracking performance of lower limb exoskeleton system dedicated for rehabilitation the motion of hip and knee limbs in disabled persons. The proposed controller together with exoskeleton device is practically instructive to make exercises for people suffering weakness in their lower limbs. The proposed controller combined both active disturbance rejection control (ADRC) with sliding mode control (SMC) to get their powerful characteristics in terms of rejection capability and robustness characteristics. The dynamic modelling of swinging lower limbs are developed and the controller has been designed accordingly. The numerical simulations have been conducted to validate the effectiveness of proposed controller. A comparison study in performance has been performed between the proposed controller and the traditional controller ADRC based on proportional-derivative controller. The simulated results showed that the proposed controller has better tracking performance than conventional version. In addition, the results showed that the sliding mode-based ADRC can considerably reduce the chattering level and better rejection capability, fast tracking behavior and less control effort.


Assuntos
Pessoas com Deficiência , Exoesqueleto Energizado , Humanos , Extremidade Inferior , Terapia por Exercício , Exercício Físico
10.
Acta Neurochir (Wien) ; 164(6): 1535-1541, 2022 06.
Artigo em Inglês | MEDLINE | ID: mdl-35511406

RESUMO

PURPOSE: Degenerative cervical myelopathy (DCM) is the most common cause of adult spinal cord dysfunction worldwide. However, the current incidence of DCM is poorly understood. The Hospital Episode Statistics (HES) database contains details of all secondary care admissions across NHS hospitals in England. This study aimed to use HES data to characterise surgical activity for DCM in England. METHODS: The HES database was interrogated for all cases of DCM between 2012 and 2019. DCM cases were identified from 5 ICD-10 codes. Age-stratified values were collected for 'Finished Consultant Episodes' (FCEs), which correspond to a patient's hospital admission under a lead clinician. Data was analysed to explore current annual activity and longitudinal change. RESULTS: 34,903 FCEs with one or more of the five ICD-10 codes were identified, of which 18,733 (53.6%) were of working age (18-64 years). Mean incidence of DCM was 7.44 per 100,000 (SD ± 0.32). Overall incidence of DCM rose from 6.94 per 100,000 in 2012-2013 to 7.54 per 100,000 in 2018-2019. The highest incidence was seen in 2016-2017 (7.94 per 100,000). The median male number of FCEs per year (2919, IQR: 228) was consistently higher than the median female number of FCEs per year (2216, IQR: 326). The rates of both emergency admissions and planned admissions are rising. CONCLUSIONS: The incidence of hospitalisation for DCM in England is rising. Health care policymakers and providers must recognise the increasing burden of DCM and act to address both early diagnoses and access to treatment in future service provision plans.


Assuntos
Doenças da Medula Espinal , Medicina Estatal , Adolescente , Adulto , Bases de Dados Factuais , Feminino , Hospitalização , Hospitais , Humanos , Masculino , Pessoa de Meia-Idade , Doenças da Medula Espinal/epidemiologia , Doenças da Medula Espinal/cirurgia , Adulto Jovem
11.
Medicina (Kaunas) ; 58(2)2022 Feb 21.
Artigo em Inglês | MEDLINE | ID: mdl-35208645

RESUMO

Background and objective: The purpose of this study is to compare the attitudes, views, and factors that influence drug abuse among pharmacy and nursing students at a Saudi Arabian university. Materials and Methods: A cross-sectional study, was conducted among pharmacy and nursing students who are currently enrolled in the respective courses at the study site. The data were collected over 4 months from August to November 2019 using structured self-administered paper-based questionnaires. Results: Among the participants, pharmacy students accounted for 184 (58.2%) while 132 (41.8%) of the students were from nursing. More than a third of the students 129, (40.8%) smoked cigarettes. The majority of pharmacy (80.4%) and nursing students (67.4%) reported having undertaken a drug misuse course in college. Among the participants, 132 (41.7%) stated that an offer from friends, followed by joy seeking 129 (40.8%), parents' divorce 126 (39.8%), having access to drugs 125 (39.5%), family issues 110 (34.8%), 66 (20.8%) having a family member who is addicted, and 101 (31.9%) reported curiosity to be the factors regarding the use of abusive drugs. Transient euphoria (75.9%) followed by depression 197 (62.3%) was the most prevalent physical or psychological change that occurred following drug use. The family size and father's education have significantly affected the attitudes scores of the students (F = 5.188; p = 0.0001). Conclusion: In this study, joy-seeking, access to drugs, and family issues were found to be the major factors listed as reasons for drug abuse, with some of them being controllable or reversible. Educating about the adverse outcomes of abused drugs is warranted.


Assuntos
Drogas Ilícitas , Estudantes de Farmácia , Atitude , Estudos Transversais , Atenção à Saúde , Demografia , Humanos , Arábia Saudita/epidemiologia , Estudantes de Farmácia/psicologia , Inquéritos e Questionários
12.
Malays J Pathol ; 44(1): 115-120, 2022 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-35484894

RESUMO

INTRODUCTION: Malignant peripheral nerve sheath tumour (MPNST) is an uncommon malignant neoplasm of childhood with unfavourable prognosis. Only a limited number of cases have been reported in children less than 12 years of age, and approximately one-half arise from a benign peripheral nerve sheath tumour, especially in the background of neurofibromatosis type 1 (NF1). Primary MPNST in children is even rarer. CASE REPORT: A 3-year-old Malay girl presented with painful right axillary swelling for six months, initially treated as axillary lymphadenitis and she defaulted follow up. She came back four months later with enlargement of the swelling. The previous biopsy was reported as Schwannoma, which correlates with a benign peripheral nerve sheath tumour's MRI findings. The final diagnosis after debulking surgery was consistent with MPNST. She succumbed to death 20 months after her initial diagnosis of advanced MPNST and lung metastasis. PATHOLOGICAL FINDINGS: Grossly, a huge partly circumscribed soft tissue mass was noted arising from a nerve with a solid greyish yellowish myxoid cut surface. Spindle-shaped cells arranged in a herringbone pattern alternated with areas of myxoid hypocellular areas exhibited marked pleomorphism, brisk mitosis, and extensive necrosis are seen microscopically. Immunohistochemistry shows patchy S100 protein staining with loss of expression of H3K27me3. CONCLUSION: Although MPNST is rare in the paediatric age group, the diagnosis should be considered in children without NF1 with a rapidly evolving and painful mass in the peripheral nerve distribution. In this case, the diagnosis was delayed and made after surgery. Due to its morphologic heterogeneity and lack of specific immunohistochemical markers, MPNST remains a diagnostic challenge.


Assuntos
Neoplasias de Bainha Neural , Neurilemoma , Neurofibrossarcoma , Pré-Escolar , Feminino , Humanos , Imuno-Histoquímica , Neoplasias de Bainha Neural/diagnóstico , Neoplasias de Bainha Neural/patologia , Neurilemoma/diagnóstico , Neurilemoma/patologia , Neurofibrossarcoma/diagnóstico , Neurofibrossarcoma/patologia , Proteínas S100
13.
Pak J Med Sci ; 38(1): 57-61, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35035401

RESUMO

OBJECTIVE: To assess proliferative diabetic retinopathy (PDR) and to describe the difference in angiographic representation of new vessels (NVs) and Intra retinal microvascular abnormalities (IRMA) on optical coherence tomography angiography (OCTA). METHODS: A cross-sectional observational study was performed at ISRA Postgraduate Institute of Ophthalmology, Karachi, from March 2018 to September 2018. Forty-two eyes of 21 patients with history of diabetes mellitus (DM) were examined. Twenty-eight eyes with a clinical diagnosis of severe non proliferative diabetic retinopathy (NPDR) or proliferative diabetic retinopathy (PDR) according to early treatment diabetic retinopathy study (ETDRS) were included and evaluated using Swept source optical coherence tomography angiography (SS-OCTA). Then face wide field SS-OCTA images and co registered structural optical coherence tomography (OCT) with flow overlay were used to distinguish the features of IRMA and retinal NVs. RESULTS: Forty-two eyes (21 patients) were examined clinically. Fourteen eyes had moderate NPDR, 15 had severe NPDR and 13 eyes had changes consistent with PDR. After clinical diagnosis, we included 28 eyes in our study based on inclusion criteria. These 28 eyes went through SS-OCTA evaluation and we observed 15 cases with PDR and 13 with severe NPDR changes. The OCTA and clinical diagnosis were similar except in 2 eyes, which is critical but not statically significant showing the importance of this noninvasive technology. CONCLUSIONS: Widefield OCTA can work as an alternative to fundus fluorescein angiography (FFA) in the diagnosis of diabetic retinopathy (DR). As it is a non-invasive and depth encoded technique so can be used frequently to monitor the retinal changes and their progression.

14.
Chemistry ; 27(60): 14971-14980, 2021 Oct 25.
Artigo em Inglês | MEDLINE | ID: mdl-34403562

RESUMO

The seven-membered cyclic potassium alumanyl species, [{SiNMes }AlK]2 [{SiNMes }={CH2 SiMe2 N(Mes)}2 ; Mes=2,4,6-Me3 C6 H2 ], which adopts a dimeric structure supported by flanking K-aryl interactions, has been isolated either by direct reduction of the iodide precursor, [{SiNMes }AlI], or in a stepwise manner via the intermediate dialumane, [{SiNMes }Al]2 . Although the intermediate dialumane has not been observed by reduction of a Dipp-substituted analogue (Dipp=2,6-i-Pr2 C6 H3 ), partial oxidation of the potassium alumanyl species, [{SiNDipp }AlK]2 , where {SiNDipp }={CH2 SiMe2 N(Dipp)}2 , provided the extremely encumbered dialumane [{SiNDipp }Al]2 . [{SiNDipp }AlK]2 reacts with toluene by reductive activation of a methyl C(sp3 )-H bond to provide the benzyl hydridoaluminate, [{SiNDipp }AlH(CH2 Ph)]K, and as a nucleophile with BPh3 and RN=C=NR (R=i-Pr, Cy) to yield the respective Al-B- and Al-C-bonded potassium aluminaborate and alumina-amidinate products. The dimeric structure of [{SiNDipp }AlK]2 can be disrupted by partial or complete sequestration of potassium. Equimolar reactions with 18-crown-6 result in the corresponding monomeric potassium alumanyl, [{SiNDipp }Al-K(18-cr-6)], which provides a rare example of a direct Al-K contact. In contrast, complete encapsulation of the potassium cation of [{SiNDipp }AlK]2 , either by an excess of 18-cr-6 or 2,2,2-cryptand, allows the respective isolation of bright orange charge-separated species comprising the 'free' [{SiNDipp }Al]- alumanyl anion. Density functional theory (DFT) calculations performed on this moiety indicate HOMO-LUMO energy gaps in the of order 200-250 kJ mol-1 .

15.
Chemistry ; 27(52): 13221-13234, 2021 Sep 15.
Artigo em Inglês | MEDLINE | ID: mdl-34190374

RESUMO

The addition of PPh2 H, PPhMeH, PPhH2 , P(para-Tol)H2 , PMesH2 and PH3 to the two-coordinate Ni0 N-heterocyclic carbene species [Ni(NHC)2 ] (NHC=IiPr2 , IMe4 , IEt2 Me2 ) affords a series of mononuclear, terminal phosphido nickel complexes. Structural characterisation of nine of these compounds shows that they have unusual trans [H-Ni-PR2 ] or novel trans [R2 P-Ni-PR2 ] geometries. The bis-phosphido complexes are more accessible when smaller NHCs (IMe4 >IEt2 Me2 >IiPr2 ) and phosphines are employed. P-P activation of the diphosphines R2 P-PR2 (R2 =Ph2 , PhMe) provides an alternative route to some of the [Ni(NHC)2 (PR2 )2 ] complexes. DFT calculations capture these trends with P-H bond activation proceeding from unconventional phosphine adducts in which the H substituent bridges the Ni-P bond. P-P bond activation from [Ni(NHC)2 (Ph2 P-PPh2 )] adducts proceeds with computed barriers below 10 kcal mol-1 . The ability of the [Ni(NHC)2 ] moiety to afford isolable terminal phosphido products reflects the stability of the Ni-NHC bond that prevents ligand dissociation and onward reaction.

16.
Inorg Chem ; 60(21): 16256-16265, 2021 Nov 01.
Artigo em Inglês | MEDLINE | ID: mdl-34661399

RESUMO

A combined experimental and computational study of the structure and reactivity of two [RuZn2Me2] complexes, neutral [Ru(PPh3)(Ph2PC6H4)2(ZnMe)2] (2) and cationic [Ru(PPh3)2(Ph2PC6H4)(ZnMe)2][BArF4] ([BArF4] = [B{3,5-(CF3)2C6H3}4]) (3), is presented. Structural and computational analyses indicate these complexes are best formulated as containing discrete ZnMe ligands in which direct Ru-Zn bonding is complemented by weaker Zn···Zn interactions. The latter are stronger in 2, and both complexes exhibit an additional Zn···Caryl interaction with a cyclometalated phosphine ligand, this being stronger in 3. Both 2 and 3 show diverse reactivity under thermolysis and with Lewis bases (PnBu3, PCy3, and IMes). With 3, all three Lewis bases result in the loss of [ZnMe]+. In contrast, 2 undergoes PPh3 substitution with PnBu3, but with IMes, loss of ZnMe2 occurs to form [Ru(PPh3)(C6H4PPh2)(C6H4PPhC6H4Zn(IMes))H] (7). The reaction of 3 with H2 affords the cationic trihydride complex [Ru(PPh3)2(ZnMe)2(H)3][BArF4] (12). Computational analyses indicate that both 12 and 7 feature bridging hydrides that are biased toward Ru over Zn.

17.
Eur Spine J ; 30(10): 2791-2799, 2021 10.
Artigo em Inglês | MEDLINE | ID: mdl-33184702

RESUMO

OBJECTIVE: The goal of this study was to review the incidence of complications and unplanned re-operations after surgery for metastatic spinal tumors. BACKGROUND: The spinal column is the most common osseous site for metastatic spread. The goals of the treatment of spinal metastases are largely palliative. The surgical aims include establishing a diagnosis, providing stability, relieving neurological compression and deterioration, decreasing pain and increasing patient independence. Patients with spinal metastases who undergo surgery are considered high risk, with higher morbidity and mortality rates. MATERIALS AND METHODS: A systematic review was undertaken; PubMed and Embase databases were searched between (2010-2020) for relevant publications in English language with the following search items: metastasis OR metastases AND spine AND surgery AND complications OR revision. Using a standard PRISMA template, 2293 articles were identified. Full-text articles of interest were assessed for inclusion criteria of greater than 30 patients. RESULTS: A final number of 19 articles fully met the search criteria. Four were level II evidence, and the remaining were level III/IV. Surgical site infection 6.5% (135/2088) was reported as the main complication following surgery for spinal metastases followed by neurological deterioration 3.3% (53/1595) and instrumentation failure 2.0% (30/1501). Re-operation rate was 8.3% (54/651), with SSI (27.8%) being the most common reason for revision surgery. CONCLUSION: Patients with spinal metastases frequently present with complex therapeutic challenges requiring multidisciplinary team assessment. Surgical site infection (6.5%) was the main reason for a re-operation in patients undergoing surgery for spinal metastases.


Assuntos
Neoplasias da Coluna Vertebral , Humanos , Procedimentos Neurocirúrgicos , Reoperação , Neoplasias da Coluna Vertebral/cirurgia , Coluna Vertebral , Infecção da Ferida Cirúrgica
18.
Hemoglobin ; 45(4): 239-244, 2021 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-34794358

RESUMO

Immigration impact on genetic epidemiology of thalassemia worldwide is well-recognized. Over the past decade, the Duhok Province of Northern Iraq attracted a large number of immigrants. To assess whether immigration had contributed to changes in the mutation spectrum of ß-thalassemia (ß-thal) in the region, we recruited 218 registered patients with symptomatic ß-thal. The recruited patients included 50 (22.9%) from resettled migrant families. A total of 431 ß-thal alleles were fully characterized, with 20 different thalassemia mutations, the most frequent being IVS-II-1 (G>A) (HBB: c.315 + 1G>A), IVS-I-6 (T>C) (HBB: c.92 + 6T>C), codon 5 (-CT) (HBB: c.17_18delCT), IVS-I-110 (G>A) (HBB: c.93-21G>A), codon 44 (-C) (HBB: c.135delC), codon 8 (-AA) (HBB: c.25_26delAA) and IVS-I-1 (G>A) (HBB: c.92 + 1G>A) constituting 72.8% of the total. Some differences in mutation spectrum were observed compared to earlier studies from this same province, the most notable of which were the higher frequencies of IVS-I-110 and codon 8. Interestingly, the highest proportions of alleles related to immigrants were encountered in these two allele groups. Ethnic variation was also documented, so that while Muslim Kurds had IVS-II-1, IVS-I-6, IVS-I-110, codon 5 and codon 44 as their most frequent mutations, the most frequent among Kurdish Yazidis, were codon 5, codon 44, codon 8 and IVS-I-6. These ethnic variations and changes in mutation spectrums are important and should be taken in consideration to ensure effective implementation of the thalassemia preventive program.


Assuntos
Talassemia beta , Análise Mutacional de DNA , Emigração e Imigração , Etnicidade , Frequência do Gene , Genótipo , Humanos , Iraque/epidemiologia , Mutação , Globinas beta/genética , Talassemia beta/etnologia , Talassemia beta/genética
19.
Angew Chem Int Ed Engl ; 60(26): 14390-14393, 2021 Jun 21.
Artigo em Inglês | MEDLINE | ID: mdl-33899319

RESUMO

Copper-alumanyl complexes, [LCu-Al(SiNDipp )], where L=carbene=NHCiPr (N,N'-diisopropyl-4,5-dimethyl-2-ylidene) and Me2 CAAC (1-(2,6-diisopropylphenyl)-3,3,5,5-tetramethyl-pyrrolidin-2-ylidene) and featuring unsupported Al-Cu bonds, have been prepared. Divergent reactivity observed with carbodiimides and CO2 implies an ambiphilicity in the Cu-Al interaction that is dependent on the identity of the carbene co-ligand.

20.
Niger J Clin Pract ; 24(8): 1200-1205, 2021 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-34397031

RESUMO

OBJECTIVE: The aim of this study was to investigate the potential relationship between the volumetric area of the upper airway and rheumatoid arthritis (RA) by comparing upper airway measurements between patients with and without RA. METHODS: This case-control study compared upper airway measurements between patients with and without RA using lateral cephalometric radiographs. Two distinct measurements were made: the area of the upper airway, which is defined as "the area extending from the point of the retro-palatal region to the base of the epiglottis," and the distance of the upper airway, which is defined as "the distance between the anterior border of the third cervical vertebra (C3) and the anterior border of the soft tissue of the neck". A single examiner performed all measurements, and the intra-examiner reliability was assessed. RESULTS: Sixty-one RA patients and 95 non-RA patients were included in the case and control groups, respectively. RA patients were significantly older in age and with higher BMI values. Patients with or without RA had Angle Class II as the most prevalent orthodontic classification. The upper airway was slightly narrower in RA patients, resulting in a smaller area, and the length of the upper airway was significantly longer in RA patients. CONCLUSION: Patients with RA have narrower upper airways as measured on lateral cephalometric radiographs. This may partially explain the high prevalence of obstructive sleep apnea among patients with RA. Focusing on airways measurements when cephalometric radiographs are taken for patients with RA could give some idea about which patient is likely to have OSA.


Assuntos
Artrite Reumatoide , Apneia Obstrutiva do Sono , Artrite Reumatoide/diagnóstico por imagem , Estudos de Casos e Controles , Cefalometria , Humanos , Faringe , Reprodutibilidade dos Testes
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