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1.
Chem Commun (Camb) ; 60(70): 9372-9375, 2024 Aug 27.
Artigo em Inglês | MEDLINE | ID: mdl-39139106

RESUMO

Ketenyl lithium compounds of type [RC(Li)CO] (with R = Ph2P(E), E = O, S, Se) were found to exhibit lower thermal stabilities than their potassium analogues due to the stronger coordination of the oxygen of the ketene moiety to the harder metal cation, resulting in a more pronounced ynolate character. Using additional ligands allows manipulation of the O-Li interaction, thereby influencing the stability and reactivity of the ketenyl anions.

2.
Organometallics ; 43(4): 585-593, 2024 Feb 26.
Artigo em Inglês | MEDLINE | ID: mdl-38425382

RESUMO

Ketenyl anions are versatile intermediates in synthetic chemistry and have recently become accessible as isolable reagents from metalated ylides by exchange of the phosphine with CO. Herein, we report on a systematic study of substituent effects on the structure and bonding situation in ketenyl anions. A series of phosphinoyl-substituted ketenyl anions {[R2P(X)CCO]- with X = O, NTol, S, Se} were prepared by carbonylation of the corresponding yldiides and isolated as their corresponding potassium salts. NMR and IR spectroscopic analyses together with computational studies demonstrate that the more electron-withdrawing oxo- and iminophosphinoyl substituents increase the s-character in the bond to the ketene moiety and hence the ynolate character of the anion. This trend is particularly seen in solution, whereas the solid-state properties are influenced by packing effects affecting the bonding situation.

3.
Cureus ; 15(9): e45933, 2023 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-37885554

RESUMO

BACKGROUND:  Parkinson's disease (PD) is the second most common neurodegenerative disorder. Though the cardinal features of PD are motor symptoms, it is also associated with many non-motor symptoms, such as cognitive impairment, autonomic dysfunction, sleep disorders, and depression, which could affect the quality of life. Early identification of PD's non-motor signs can aid in the diagnosis of PD. The current research aimed to assess the neurophysiological changes in PD patients using auditory evoked P300 potential and to determine the possible correlation between P300 wave components and cognitive impairment. MATERIALS AND METHODS:  This cross-sectional research involved 32 idiopathic PD patients. The neurophysiological changes in PD patients were studied using auditory evoked P300 potential and the obtained data were compared with normative data. The patient's cognitive status was scored using the Montreal Cognitive Assessment (MoCA) questionnaire and they were divided into two groups: the patients with normal cognition and the patients with impaired cognition. RESULTS:  The participants showed a significant decrease in P300 amplitude (p = 0.000) but no change in P300 latency when compared to normative data using the Wilcoxon rank sum test. Also, there was a positive correlation between the MoCA score and P300 amplitude (p < 0.05), indicating that if cognition is impaired, P300 amplitude would also be reduced. There was a significant difference between PD patients with impaired cognition and patients with normal cognition in the P300 amplitude at Cz (p = 0.001) and Fz (p = 0.003) when the Mann-Whitney U test was used. These findings indicate that it is possible to notice changes in the P300 wave components among PD patients when their cognition is impaired. CONCLUSION:  Auditory evoked P300 potentials can be used to objectively evaluate cognition in PD patients and by starting supportive therapy, the quality of life for PD patients can be improved.

4.
Ann Indian Acad Neurol ; 26(1): 33-38, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37034036

RESUMO

Background: Natural history and disease progression in patients with Idiopathic Parkinson's Disease (PD) is quite heterogeneous. Autonomic dysfunction occurs commonly among Idiopathic PD patients. Heart rate variability and ambulatory blood pressure monitoring are used to assess cardiac autonomic dysfunction. The prevalence and magnitude of supine hypertension in Indian PD patients has not been studied to date. The present study aimed to record cardiovascular autonomic functions and supine hypertension in PD patients and to correlate them with the age of onset, duration and severity of the disease, and non-motor symptom burden. Material and Methods: The cross-sectional study involved 60 PD patients. Webster rating scale was used to determine the disease severity. Non-motor symptom burden was assessed using the Non-Motor Symptom Scale (NMSS). Ambulatory blood pressure monitoring and heart rate variability parameters determined cardiac autonomic function. Supine hypertension was defined as Systolic Blood Pressure (SBP) ≥150 mmHg and/or DBP ≥90 mmHg. Less than 10% decrease or even increase in blood pressure during the night were classified as non-dippers. Pearson coefficient was used appropriately to establish correlation. P ≤ 0.05 was considered significant. Results: Age of onset was 61.2 ± 8.7 years and duration of disease was 1.7 ± 1.1 years. Mean Webster and non-motor symptom scores were 12.7 ± 4.4 and 15.5 ± 8.0, respectively. About 50 patients (83%) were non-dipper, while 32 (53%) had supine hypertension. Low Frequency oscillations (LF) (r = 0.28), High Frequency oscillations (HF) (r = 0.29), Standard Deviation NN intervals (SDNN) (0.26), and Root Mean Squared Successive Differences of NN intervals (RMSSD) (r = 0.28) correlated significantly with non-motor symptoms scale. LF (r = -0.39), HF (r = -0.43), SDNN (-0.40), RMSSD (r = -0.41), NN50 (r = -0.38), PNN50 (r = -0.42), mean SBP (r = 0.26), and mean DBP (r = 0.33) correlated significantly with disease duration. PNN50 (r = -0.255), mean SBP (r = -0.29), and mean DBP (r = -0.27) correlated significantly with age at onset. Conclusion: Awareness regarding neurogenic supine hypertension is needed as it occurs commonly among Indian PD patients. Heart rate variability (HRV) parameters and ambulatory blood pressure are of significant help in the detection of early cardiovascular autonomic dysfunction and correlate significantly with disease duration and non-motor symptom burden among PD patients.

5.
Chem Commun (Camb) ; 59(1): 110-113, 2022 Dec 22.
Artigo em Inglês | MEDLINE | ID: mdl-36477167

RESUMO

The hydroamination of electron-deficient olefins was carried out using the (CAAC)Cu-Cl (CAAC = cyclic (alkyl)(amino)carbene) catalyst with an excellent yield at room temperature and under an open atmosphere. Furthermore, the catalyst shows excellent efficiency in the hydroaryloxylation and hydroalkoxylation of alkenes under mild conditions. The efficiency of the catalyst was tested for a wide range of substrates with different electronic and steric functionalities. Detailed computational studies have been carried out to understand the mechanism of these Cu(I) catalyzed reactions, which revealed that the reaction proceeds via either a four-membered or a six-membered cyclic transition state containing the copper ion.


Assuntos
Alcenos , Cobre , Alcenos/química , Cobre/química , Elétrons , Catálise
6.
J Altern Complement Med ; 24(12): 1181-1188, 2018 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-30160530

RESUMO

Background: This study was conducted to test the hypothesis that prenatal yogic exercises are effective in alleviating labor pain and improving birth outcomes, by comparing pregnant women undertaking yoga with a control group. Trial design: Single blinded, parallel randomized control trial. Methods: Two hundred primigravid women of 30 weeks of gestation onward who met the inclusion criteria (primigravida, 20-35 years of age, gestational age of 30 weeks, no prior experience of yoga) were randomly assigned to study (n = 100) and control groups (n = 100) by using the minimized randomization program version 2.01. The study group received the intervention in the form of integrated yoga consisting of a series of 30-min practice sessions at the 30th, 32nd, 34th, 36th, 37th, 38th, and 39th weeks of gestational age. The matched control group did not perform yoga. The patients were followed till delivery for maternal comfort, alleviation of labor pain, and birth outcome. Alleviation of labor pain was assessed by using numerical pain intensity scale (NPIS), pain behavioral observational scale (PBOS), and maternal delivery comfort questionnaire. Only the assessors were blinded. Results: Two hundred patients were randomized into 100 each in case and control groups. Final analysis was done on 75 patients in each group after exclusion due to development of complications, loss to follow-up. The requirement of induction of labor and analgesics was significantly less in the study group (p < 0.044, p < 0.045). There was significantly more number of normal vaginal deliveries (p < 0.037) and less caesarean sections (p < 0.048), shorter first stage of labor (p < 0.0003) in the study group practicing yoga. The tolerance of pain was better in the study group as shown by NPIS (p < 0.001) and PBOS scores (p < 0.0001). Postpartum, the maternal comfort questionnaire score showed higher comfort in the study group (p < 0.032). The number of low birth weight babies was also significantly less in the study group (p < 0.042). There were no adverse effects attributed to yoga. Conclusion: The study has highlighted that yoga is a noninvasive, easy to learn mind-body medicine and complementary health practice, effective in alleviation of labor pain and possibly improving birth outcome.


Assuntos
Terapia por Exercício/métodos , Dor do Parto/terapia , Trabalho de Parto/fisiologia , Meditação/métodos , Cuidado Pré-Natal/métodos , Yoga , Adulto , Feminino , Humanos , Gravidez , Resultado da Gravidez , Adulto Jovem
7.
J Clin Diagn Res ; 10(12): CM04-CM06, 2016 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-28208852

RESUMO

INTRODUCTION: Altered cardiac autonomic functions in form of reduced Heart Rate Variability (HRV) have been found to be associated with increased cardiovascular morbidity and mortality in depressive patients. AIM: To investigate the relationship between HRV measures, which is a non-invasive marker of autonomic nervous system and depression. MATERIALS AND METHODS: The study included a convenient sample size of drug naive depressive patients (n=30) diagnosed on basis of ICD-10 and compared with age and gender matched healthy volunteers (n=30). Five minute ECG recording was done for HRV analysis and frequency domain measures like LF (Low Frequency), HF (High Frequency), LF/HF ratio as well as time domain measures like SDNN (Standard Deviation of all NN interval) and RMSSD (Root Mean Square of Successive differences of NN intervals) were obtained. RESULTS: In the frequency domain parameters, values of LF (nu) and LF/HF Ratio were found to be significantly higher (p<0.001) whereas, that of HF (nu) was significantly lower (p<0.001) in depression group as compared to control group. However, in the time domain parameters, no significant difference was observed in SDNN and RMSSD values in between the two groups. CONCLUSION: HRV recordings showed significant changes in frequency domain parameters in the patients suffering from depression. Thus, it could be said from our study that autonomic imbalance reflecting enhanced sympathetic activation relative to parasympathetic component is associated with depression.

8.
Int J Yoga ; 4(1): 26-32, 2011 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-21654972

RESUMO

BACKGROUND: Stress is often associated with an increased occurrence of autonomic, cardiovascular, and immune system pathology. This study was done to evaluate the impact of stress on psychological, physiological parameters, and immune system during medical term -academic examination and the effect of yoga practices on the same. MATERIALS AND METHODS: The study was carried out on sixty first-year MBBS students randomly assigned to yoga group and control group (30 each). The yoga group underwent integrated yoga practices for 35 minutes daily in the presence of trained yoga teacher for 12 weeks. Control group did not undergo any kind of yoga practice or stress management. Physiological parameters like heart rate, respiratory rate, and blood pressure were measured. Global Assessment of Recent Stress Scale and Spielbergers State Anxiety score were assessed at baseline and during the examination. Serum cortisol levels, IL-4, and IFN-γ levels were determined by enzyme-linked immunosorbent assay technique. RESULT: In the yoga group, no significant difference was observed in physiological parameters during the examination stress, whereas in the control group, a significant increase was observed. Likewise, the indicators of psychological stress showed highly significant difference in control group compared with significant difference in yoga group. During the examination, the increase in serum cortical and decrease in serum IFN-γ in yoga group was less significant (P<0.01) than in the control group (P<0.001). Both the groups demonstrated an increase in serum IL-4 levels, the changes being insignificant for the duration of the study. CONCLUSION: Yoga resists the autonomic changes and impairment of cellular immunity seen in examination stress.

9.
Indian J Physiol Pharmacol ; 55(1): 53-9, 2011.
Artigo em Inglês | MEDLINE | ID: mdl-22315810

RESUMO

Adolescent girls are at high risk of developing iron deficiency because of increased iron demands during puberty, menstrual losses, and limited dietary iron intake. This study was carried out to demonstrate the effects of Iron Deficiency Anemia on Audiovisual reaction time in adolescent girls. Adolescent girls between 17-19 years of age with similar socioeconomic background were recruited from college of nursing for the study. They were all screened and categorized into two groups depending on their haemoglobin status. Students having Hb > 12 gm/dl formed the control group i.e. Group I (n=30). All students having Hb < 12 gm/dl and S. Ferritin < 12 microg/dl formed group II i.e. iron deficient anemic (IDA) group. The following haematological parameters were studied Hemoglobin (Hb), MCV, MCH, MCHC (using Sysmex kx-21 Autoanalyser), Serum.Iron, TIBC (Spectrophotometry), Serum.Ferritin (ELISA). Auditory and Visual reaction time were measured by reaction time instrument supplied by Medicaid system, chandigarh. The mean Hb levels in Group I was 12.93 +/- 0.86 and Group II was 10.08 +/- 0.51 (P<0.001). The MCV, MCH, MCHC, S. Iron, S. Ferritin was also significantly less in group II as compared to group I (P<0.001). TIBC was significantly more in group II as compared to group I (P<0.001). Results showed that both ART and VRT were significantly increased (P<0.001) in iron deficient adolescents suggesting a deterioration in sensorimotor performance in anemics.


Assuntos
Anemia Ferropriva/fisiopatologia , Audição , Tempo de Reação , Visão Ocular , Adolescente , Adulto , Feminino , Humanos
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