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2.
ACS Chem Neurosci ; 2024 Sep 12.
Artículo en Inglés | MEDLINE | ID: mdl-39265183

RESUMEN

Peroxisome proliferator-activated receptors (PPARs) have emerged as a promising target for the treatment of various neurodegenerative disorders. Studies have shown that both PPAR α & γ individually modulate various pathophysiological events like neuroinflammation and insulin resistance, which are known to variedly affect neurogenesis. Our study aimed to evaluate the effect of saroglitazar (SGZR), a dual PPAR agonist, on adult neurogenesis and spatial learning and memory, in intracerebroventricular streptozotocin (ICV STZ)-induced dementia in rats. We have found that SGZR at the dose of 4 mg/kg per oral showed significant improvement in learning and memory compared to ICV STZ-treated rats. A substantial increase in neurogenesis was observed in the subventricular zone (SVZ) and the dentate gyrus (DG), as indicated by an increase in the number of 5-bromo-2'-deoxyuridine (BrdU)+ cells, BrdU+ nestin+ cells, and doublecortin (DCX)+cells. Treatment with SGZR also decreased the active form of glycogen synthase kinase 3ß (GSK3ß) and hence enhanced the nuclear translocation of the ß-catenin. Enhanced expression of Wnt transcription factors and target genes indicates that the up-regulation of Wnt signaling might be involved in the observed increase in neurogenesis. Hence, it can be concluded that the SGZR enhances memory functions and adult neurogenesis via the upregulation of Wnt ß-catenin signaling in ICV STZ-treated rats.

4.
Neuropediatrics ; 2024 Jul 29.
Artículo en Inglés | MEDLINE | ID: mdl-39074800

RESUMEN

BACKGROUND: Supratentorial intraventricular tumors, encompassing lateral and third ventricular tumors, are uncommon intracranial neoplasms, typically slow-growing and benign, manifesting symptoms only upon reaching a substantial size. This study aims to identify optimal surgical approaches, assess the prevalence and characteristics of these tumors, and evaluate postoperative outcomes among pediatric and adult age groups. METHODS: A retrospective comparative study at a tertiary care hospital from January 2014 to June 2020 included 165 patients (68 pediatrics, 97 adults) meeting inclusion criteria for intraventricular tumor management. Data covered demographic factors, clinical history, neurological assessments, neuroimaging, surgical approaches, histopathological diagnoses, immunohistochemical features, adjuvant therapies, follow-up status, postoperative complications, and morbidity/mortality. RESULTS: Ventricular tumor incidence showed male preponderance in both adults (M:F = 1.2:1) and pediatrics (M:F = 3:1). Lateral ventricles were the most common location. Pediatric cases exhibited more frequent calcifications on computed tomography scans (35.6% vs. 29.5%). Grade II and III tumors were more prevalent in adults within the lateral ventricle (27.1 and 1.9%) compared with pediatrics (6.5 and 8.4%). The third ventricle predominantly featured benign lesions, with pediatric patients experiencing significantly longer hospital stays (16.12 ± 21.94 days vs. 9.58 ± 6.21 days) (p = 0.006). Adults and pediatric patients showed a significant difference in high-grade lateral ventricle tumors (p-value = 0.002*). CONCLUSIONS: Supratentorial ventricular tumors are relatively more prevalent in children than adults, presenting challenges due to size and bleeding risks. Surgical resection is the primary treatment, with a focus on the optimal approach for gross total excision to reduce recurrence risk.

5.
World Neurosurg ; 189: e652-e661, 2024 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-38945207

RESUMEN

BACKGROUND: Craniovertebral junction (CVJ) tumors are challenging due to their unique anatomical location. This study aimed to evaluate the complexities in dealing with such precarious CVJ extradural lesions over the decade. METHODS: Twenty-seven patients of extradural CVJ tumors operated between 2009 and 2018 were included. The demographic details, neurological status, surgical approach, extent of resection, type of fixation, complications, and outcome at final follow-up were recorded for each patient. RESULTS: The mean age of the patients was 39.5 ± 20 years. Most (17/27) of the patients had involvement of a single level. Clivus was the most common (9/17) involved region followed by atlas (7/17) vertebrae. Majority of the patients (13/27) were operated through the posterior-only approach. About 15 patients (55.5%) had instability or extensive lesions that necessitated posterior fixation. None of the patients underwent anterior fixation. Gross and near total excision were achieved in 10 patients (37%) and 3 patients (11%) respectively while 14 patients underwent subtotal excision of tumor. On histopathological analysis, clival chordoma (8/27) was found to be the most common pathology followed by giant cell tumor (6/27), plasmacytoma (4/27), and multiple myeloma (2/27). Most patients (13 out of 27) had the same neurological status after the surgery. Six patients (22%) improved post-operatively with decreased weakness and spasticity. Thirteen (48%) patients underwent adjuvant radiotherapy. CONCLUSIONS: This retrospective study provides valuable insights into managing extradural CVJ tumors and highlights the importance of individualized approaches for optimal outcome.


Asunto(s)
Neoplasias de la Base del Cráneo , Neoplasias de la Médula Espinal , Humanos , Persona de Mediana Edad , Adulto Joven , Estudios Retrospectivos , Neoplasias de la Base del Cráneo/tratamiento farmacológico , Neoplasias de la Base del Cráneo/patología , Neoplasias de la Base del Cráneo/cirugía , Neoplasias de la Médula Espinal/tratamiento farmacológico , Neoplasias de la Médula Espinal/patología , Neoplasias de la Médula Espinal/cirugía , Resultado del Tratamiento , Medicina de Precisión , Masculino , Femenino
6.
Chem Commun (Camb) ; 60(33): 4495-4498, 2024 Apr 18.
Artículo en Inglés | MEDLINE | ID: mdl-38567462

RESUMEN

We have demonstrated that cisplatin (CP), an anticancer drug, showed a preference for binding the sulfated-L-iduronic acid (S-L-IdoA) unit over the sulfated-D-glucuronic acid unit of heparan sulfate. The multivalency of S-L-IdoA, such as in the proteoglycan mimic, resulted in distinct modes of cell-surface engineering in normal and cancer cells, with these disparities having a significant impact on CP-mediated toxicity.


Asunto(s)
Cisplatino , Proteoglicanos , Heparitina Sulfato/química , Ácido Glucurónico/metabolismo , Ácido Idurónico , Sulfatos
7.
Radiology ; 310(2): e232365, 2024 02.
Artículo en Inglés | MEDLINE | ID: mdl-38349244

RESUMEN

Background Image-guided tumor ablation is the first-line therapy for early-stage hepatocellular carcinoma (HCC), with ongoing investigations into its combination with immunotherapies. Matrix metalloproteinase (MMP) inhibition demonstrates immunomodulatory potential and reduces HCC tumor growth when combined with ablative treatment. Purpose To evaluate the effect of incomplete cryoablation with or without MMP inhibition on the local immune response in residual tumors in a murine HCC model. Materials and Methods Sixty 8- to 10-week-old female BALB/c mice underwent HCC induction with use of orthotopic implantation of syngeneic Tib-75 cells. After 7 days, mice with a single lesion were randomized into treatment groups: (a) no treatment, (b) MMP inhibitor, (c) incomplete cryoablation, and (d) incomplete cryoablation and MMP inhibitor. Macrophage and T-cell subsets were assessed in tissue samples with use of immunohistochemistry and immunofluorescence (cell averages calculated using five 1-µm2 fields of view [FOVs]). C-X-C motif chemokine receptor type 3 (CXCR3)- and interferon γ (IFNγ)-positive T cells were assessed using flow cytometry. Groups were compared using unpaired Student t tests, one-way analysis of variance with Tukey correction, and the Kruskal-Wallis test with Dunn correction. Results Mice treated with incomplete cryoablation (n = 6) showed greater infiltration of CD206+ tumor-associated macrophages (mean, 1.52 cells per FOV vs 0.64 cells per FOV; P = .03) and MMP9-expressing cells (mean, 0.89 cells per FOV vs 0.11 cells per FOV; P = .03) compared with untreated controls (n = 6). Incomplete cryoablation with MMP inhibition (n = 6) versus without (n = 6) led to greater CD8+ T-cell (mean, 15.8% vs 8.29%; P = .04), CXCR3+CD8+ T-cell (mean, 11.64% vs 8.47%; P = .004), and IFNγ+CD8+ T-cell infiltration (mean, 11.58% vs 5.18%; P = .02). Conclusion In a mouse model of HCC, incomplete cryoablation and systemic MMP inhibition showed increased cytotoxic CD8+ T-cell infiltration into the residual tumor compared with either treatment alone. © RSNA, 2024 Supplemental material is available for this article. See also the editorial by Gemmete in this issue.


Asunto(s)
Carcinoma Hepatocelular , Criocirugía , Neoplasias Hepáticas , Femenino , Animales , Ratones , Carcinoma Hepatocelular/cirugía , Inhibidores de la Metaloproteinasa de la Matriz , Neoplasias Hepáticas/cirugía , Linfocitos T CD8-positivos , Metaloproteinasas de la Matriz
9.
NMR Biomed ; 37(5): e5102, 2024 May.
Artículo en Inglés | MEDLINE | ID: mdl-38263680

RESUMEN

A unique feature of the tumor microenvironment is extracellular acidosis in relation to intracellular milieu. Metabolic reprogramming in tumors results in overproduction of H+ ions (and lactate), which are extruded from the cells to support tumor survival and progression. As a result, the transmembrane pH gradient (ΔpH), representing the difference between intracellular pH (pHi) and extracellular pH (pHe), is posited to be larger in tumors compared with normal tissue. Controlling the transmembrane pH difference has promise as a potential therapeutic target in cancer as it plays an important role in regulating drug delivery into cells. The current study shows successful development of an MRI/MRSI-based technique that provides ΔpH imaging at submillimeter resolution. We applied this technique to image ΔpH in rat brains with RG2 and U87 gliomas, as well as in mouse brains with GL261 gliomas. pHi was measured with Amine and Amide Concentration-Independent Detection (AACID), while pHe was measured with Biosensor Imaging of Redundant Deviation in Shifts (BIRDS). The results indicate that pHi was slightly higher in tumors (7.40-7.43 in rats, 7.39-7.47 in mice) compared with normal brain (7.30-7.38 in rats, 7.32-7.36 in mice), while pHe was significantly lower in tumors (6.62-6.76 in rats, 6.74-6.84 in mice) compared with normal tissue (7.17-7.22 in rats, 7.20-7.21 in mice). As a result, ΔpH was higher in tumors (0.64-0.81 in rats, 0.62-0.65 in mice) compared with normal brain (0.13-0.16 in rats, 0.13-0.16 in mice). This work establishes an MRI/MRSI-based platform for ΔpH imaging at submillimeter resolution in gliomas.


Asunto(s)
Neoplasias Encefálicas , Glioma , Ratas , Ratones , Animales , Fuerza Protón-Motriz , Neoplasias Encefálicas/metabolismo , Roedores , Glioma/diagnóstico por imagen , Encéfalo/metabolismo , Imagen por Resonancia Magnética/métodos , Concentración de Iones de Hidrógeno , Microambiente Tumoral
10.
Mol Neurobiol ; 61(8): 5928-5934, 2024 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-38252382

RESUMEN

Axons are long slender portions of neurons that transmit electrical impulses to maintain proper physiological functioning. Axons in the central nervous system (CNS) and peripheral nervous system (PNS) do not exist in isolation but are found to form a complex association with their surrounding glial cells, oligodendrocytes and Schwann cells. These cells not only myelinate them for faster nerve impulse conduction but are also known to provide metabolic support. Due to their incredible length, continuous growth, and distance from the cell body (where major energy synthesis takes place), axons are in high energetic demand. The stability and integrity of axons have long been associated with axonal energy levels. The current mini-review is thus focused on how axons accomplish their high energetic requirement in a cell-autonomous manner and how the surrounding glial cells help them in maintaining their integrity by fulfilling their energy demands (non-cell autonomous trophic support). The concept that adjacent glial cells (oligodendrocytes and Schwann cells) provide trophic support to axons and assist them in maintaining their integrity comes from the conditional knockout research and the studies in which the metabolic pathways controlling metabolism in these glial cells are modulated and its effect on axonal integrity is evaluated. In the later part of the mini-review, the current knowledge of axon-glial metabolic coupling during various neurodegenerative conditions was discussed, along with the potential lacunae in our current understanding of axon-glial metabolic coupling.


Asunto(s)
Axones , Metabolismo Energético , Oligodendroglía , Células de Schwann , Células de Schwann/metabolismo , Axones/metabolismo , Animales , Oligodendroglía/metabolismo , Metabolismo Energético/fisiología , Humanos
11.
Paediatr Anaesth ; 34(4): 340-346, 2024 04.
Artículo en Inglés | MEDLINE | ID: mdl-38189558

RESUMEN

BACKGROUND AND AIMS: Airway management in children with oral cleft surgery carries unique challenges, concerning the proximity of the surgical site and the tracheal tube. We hypothesized that using a Microcuff oral RAE tube would reduce tube exchange and migration rate. We aimed to compare the performance of Microsoft and uncuffed oral performed tracheal tubes in children undergoing cleft palate surgeries regarding the rate of tracheal tube exchange, endobronchial intubation, and ventilatory parameters. METHODS: One hundred children scheduled for cleft palate surgery were randomized into two groups. In the uncuffed group (n = 50), the tracheal tube was selected using the Modified Coles formula, and in the Microcuff (n = 50) group, the manufacturer's recommendations were followed. Intraoperatively, we compared the primary outcome of tube exchange using the chi-square test. The leak pressure and ventilatory parameters after head extension and mouth gag application were measured in both groups. RESULTS: The tracheal tube exchange rate was significantly lower in the Microcuff group (0/50) than in uncuffed (19/50) preformed tubes (0 vs. 38% respectively; p <.001). The uncuffed and Microcuff tracheal tube were comparable concerning ventilation parameters and leak pressure of finally placed tubes (17.78 ± 3.95 vs. 19.26 ± 3.81 cm H2 O respectively, with a mean difference (95% CI) of -1.48 (-0.01-2.98); p-value =0.059. Cuff pressure did not vary significantly during the initial hour, and the incidence of postoperative airway morbidity between uncuffed and Microcuff tube was comparable, 5/50 (10%) versus 7/50 (14%) with risk ratio (95% CI) of 0.71(0.24-2.1), p value .49. CONCLUSION: Microcuff oral preformed tubes performed better than uncuffed tubes regarding tube exchange during cleft palate surgery.


Asunto(s)
Fisura del Paladar , Niño , Humanos , Fisura del Paladar/cirugía , Respiración , Manejo de la Vía Aérea , Periodo Posoperatorio , Intubación Intratraqueal
12.
Perfusion ; : 2676591231226161, 2024 Jan 05.
Artículo en Inglés | MEDLINE | ID: mdl-38182129

RESUMEN

BACKGROUND: Modifiable and non-modifiable factors contribute to development and progression of acute kidney injury (AKI) during cardiac surgery. We hypothesized that, the difference between preoperative mean arterial pressure (MAP) and the average mean arterial pressure maintained on cardiopulmonary bypass (CPB) would be strongly predictive of AKI. We also measured plasma Neutrophil gelatinase-associated lipocalin (NGAL), to establish its association with cardiac surgery associated-AKI (CSA-AKI). METHODS: One hundred and twelve high-risk patients undergoing valve, and valve plus coronary artery bypass grafting (CABG) surgery under cardiopulmonary bypass (CPB) were included in this study. Delta mean arterial pressure (MAP) was calculated as the difference between the average of pre-operative and on-bypass MAP, and blood was sampled for NGAL levels, at baseline, and 6-h after CPB. Detailed data collection was done, tabulating most of the factors which might influence development of post-operative cardiac surgery associated-AKI (CSA-AKI). To define CSA-AKI within the first 24-h post-operatively, the Kidney Disease Improving Global Outcomes (KDIGO) classification was used. RESULTS: Out of 112 patients, 44 (39.3%) developed CSA-AKI postoperatively. With an ROC analysis cut-off of delta MAP of more than 25.67 mmHg, 46.4% patients developed post-operative AKI, and the average CPB flows which were 1.8 ± 0.2 were not contributory to the development of early CSA-AKI. In our study, ELISA test for human NGAL was performed on serum samples, and the estimated cut-off value of 1661 ng/mL was found to be significantly associated with early CSA-AKI. CONCLUSIONS: Delta MAP and CPB flows are not related to early post-surgical CSA-AKI in cases with prior high-risk elements. However, baseline serum NGAL, as well as its percent change during the early post-surgical period independently predicted the development of CSA-AKI. This implies that, there may be patients with a higher pre-operative preponderance to develop this complication, which could actually be delineated by the use of serum NGAL estimations at baseline.

13.
Artículo en Inglés | MEDLINE | ID: mdl-38247033

RESUMEN

Cranial nerve palsies can be presenting signs of intracranial aneurysms. There is a classic pairing between an aneurysmal vessel and adjacent nerves leading to cranial neuropathy. Isolated abducens nerve palsy can be a localizing sign of an unruptured vertebrobasilar circulation aneurysm. Aneurysms involving Anterior Inferior Cerebellar Artery (AICA) and Posterior Inferior Cerebellar Artery (PICA) have been reported to be associated with abducens nerve palsy. The symptoms in unruptured aneurysms are due to the mass effect on adjacent neurovascular structures. Most of the abducens nerve palsy resolves following microsurgical clipping. Here, we present a rare case of an unruptured Posterior Cerebral Artery (PCA) aneurysm presenting with abducens nerve palsy and diplopia associated with contralateral hemianopsia which markedly improved following endovascular coil embolization.

14.
Arch Gynecol Obstet ; 309(2): 385-396, 2024 02.
Artículo en Inglés | MEDLINE | ID: mdl-37147484

RESUMEN

PURPOSE: Pre-conceptual comorbidities, an inherent risk of graft loss, rejection during pregnancy, and the postpartum period in women with thoracic lung transplant may predispose them to increased risk of adverse feto-maternal outcomes. The study aimed to systematically analyze and assess the risk of adverse pregnancy outcomes in women with thoracic organ transplant. METHODS: MEDLINE, EMBASE, and Cochrane library were searched for publication between January 1990 and June 2020. Risk of bias was assessed using Joanna Briggs critical appraisal tool for case series. The primary outcomes included maternal mortality and pregnancy loss. The secondary outcomes were maternal complications, neonatal complications, and adverse birth outcomes. The analysis was performed using the DerSimonian-Laird random effects model. RESULTS: Eleven studies captured data from 275 parturient with thoracic organ transplant describing 400 pregnancies. The primary outcomes included maternal mortality {pooled incidence (95% confidence interval) 4.2 (2.5-7.1) at 1 year and 19.5 (15.3-24.5) during follow-up}. Pooled estimates yielded 10.1% (5.6-17.5) and 21.8% (10.9-38.8) risk of rejection and graft dysfunction during and after pregnancy, respectively. Although 67% (60.2-73.2) of pregnancies resulted in live birth, total pregnancy loss and neonatal death occurred in 33.5% (26.7-40.9) and 2.8% (1.4-5.6), respectively. Prematurity and low birth weight were reported in 45.1% (38.5-51.9) and 42.7% (32.8-53.2), respectively. CONCLUSIONS: Despite pregnancies resulting in nearly 2/3rd of live births, high incidence of pregnancy loss, prematurity and low birth weight remain a cause of concern. Focused pre-conceptual counseling to avoid unplanned pregnancy, especially in women with transplant-related organ dysfunctions and complications, is vital to improve pregnancy outcomes. PROSPERO NUMBER: CRD42020164020.


Asunto(s)
Aborto Espontáneo , Trasplante de Órganos , Complicaciones del Embarazo , Embarazo , Recién Nacido , Femenino , Humanos , Resultado del Embarazo , Recién Nacido de Bajo Peso , Trasplante de Órganos/efectos adversos , Complicaciones del Embarazo/epidemiología , Complicaciones del Embarazo/etiología , Recien Nacido Prematuro
15.
Neuroradiol J ; 37(2): 221-228, 2024 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-38148622

RESUMEN

BACKGROUND: Cerebral computed tomography angiography (CTA) has revolutionized the diagnosis of neurovascular emergencies. Strategies to reduce radiation, a concern for cancer, involve tube voltage and current reduction but with increased noise and inferior image quality. Hence, the objective of the study was to evaluate the quality of images obtained through low-dose radiation and low-contrast volume CTA with an iterative reconstruction (IR) technique versus standard CTA without IR. METHODS: This prospective trial involved 100 adults requiring cerebral CTA for cerebrovascular diseases. They were split into two groups: one with 120 kVp tube voltage and 80 mL contrast using filtered back projection, and the other with 80 kVp and 30 mL contrast with IR. Evaluation criteria included attenuation values, signal-to-noise ratio, contrast-to-noise ratio, and subjective assessments. RESULTS: Compared to 120 kVp, 80 kVp showed higher vessel attenuation in the internal (272.91 ± 30.59 vs 405.52 ± 53.08; p < .001) and middle cerebral artery (247.55 ± 29.84 vs 372.55 ± 49.02; p < .001) regions. Brain parenchymal attenuation at the centrum semiovale was lower with 80 kVp (29.12 ± 1.87 vs 24.78 ± 2.94; p < .001), accompanied by higher noise. Signal-to-noise ratio (p < .001) and contrast-to-noise ratio (p < .05) were lower at 80 kVp. Image quality didn't significantly differ, and radiation exposure reduced significantly by 70% in the 80 kVp group, suggesting its diagnostic feasibility. CONCLUSIONS: The 80 kVp protocol for CTA of the cerebral vessels combined with lower contrast volume produces images with similar image quality with significant radiation effective dose and total iodine dose reduction. The 80 kVp protocol holds significant promise for replacing the standard 120 kVp protocol in cerebral CTA.


Asunto(s)
Angiografía por Tomografía Computarizada , Medios de Contraste , Adulto , Humanos , Angiografía por Tomografía Computarizada/métodos , Estudios Prospectivos , Dosis de Radiación , Interpretación de Imagen Radiográfica Asistida por Computador/métodos , Tomografía Computarizada por Rayos X/métodos
17.
J Craniovertebr Junction Spine ; 14(3): 259-267, 2023.
Artículo en Inglés | MEDLINE | ID: mdl-37860028

RESUMEN

Background: Lumbar discectomy is performed for symptomatic lumbar disc herniation and is one of the most widely performed spinal surgical procedures worldwide in a variety of ways. This survey aimed at providing an overview/perspective of different practice patterns and the impact of lumbar discectomy on axial back pain with or without sciatica. Methods: An online survey was performed using the application "Google Forms." The link to the questionnaire was distributed to neurosurgeons through personal E-mail and social media platforms. Results: We received 333 responses. The largest percentage of responses across five continents was from Asia (66.97%, n = 223). The mean age of the respondents was 40.08 ± 10.5 years. A total of 66 respondents (20%) had a spine practice of 7%-90%, and 28 respondents had a spine practice of 90%-100% (8.4%). The number of respondents who practiced microscopic discectomy using a tubular retractor (n = 143 respondents, 42.9%) was nearly equal to the number of respondents who practiced open discectomy (n = 142 respondents, 42.6%). An almost equal proportion of respondents believed discectomy does not help in relieving axial back pain. Only 20.4% (n = 68) of respondents recommend bed rest for a longer duration postoperatively. Conclusions: Our survey revealed that only 22.2% of spine surgeons recommended discectomy in patients with radiological disc herniation with axial back pain alone and preferred a minimally invasive method of discectomy. Almost half of them believed discectomy to be ineffective for axial low back pain and only a few recommended prolonged bed rest postoperatively.

18.
Environ Monit Assess ; 195(11): 1377, 2023 Oct 26.
Artículo en Inglés | MEDLINE | ID: mdl-37882874

RESUMEN

The current study determined Tor putitora (Hamilton, 1822) fishery, growth, mortality, and population characteristics using length-frequency data assembled monthly from the Tehri dam reservoir in Uttarakhand from January to December 2022. The estimation data was separated into 40-mm class intervals, and population parameters were investigated and computed using the FiSAT-II software tool. W = 0.0101 L2.996, where a = 0.0101 and b = 2.99, were determined as the length-weight relationships, and the growth performance index (ϕ) was computed to be 5.40. Tor putitora commercial catches in the Tehri dam reservoir were dominated by length groups of 360-399 and 320-359 mm. Different growth parameters were estimated using length-frequency data as L∞ = 987.00 mm, K = 0.26 yr-1, and t0 = -0.0003 years. Z, M, and F mortality coefficients were estimated to be 1.01, 0.27, and 0.73, respectively. At the end of the first, second, third, fourth, fifth, sixth, and seventh years, the fish measured 226, 400, 535, 638, 718, and 780, and 827, respectively. The estimated value of the exploitation rate (E) was 0.73 using the length-converted catch curve approach, which was determined to be somewhat higher than the optimum value (0.50). Tor putitora recruitment patterns from the Tehri dam reservoir reveal that the species only has one recruitment pattern every year, and that solely occurs from June to September. The current exploitation level (0.73) has already exceeded the maximum fishing pressure (Emax = 0.508), indicating that there is a decline in the catch at the current fishing pressure, and a further increase in fishing efforts may lead to a decline in the stock, which may be detrimental to the sustainable fishery of Tor putitora in the Tehri dam reservoir, Uttarakhand, India.


Asunto(s)
Cyprinidae , Explotaciones Pesqueras , Animales , Dinámica Poblacional , Monitoreo del Ambiente , India
19.
Prog Nucl Magn Reson Spectrosc ; 136-137: 1-60, 2023.
Artículo en Inglés | MEDLINE | ID: mdl-37716754

RESUMEN

The scalar couplings that result in the splitting of the signals in the NMR spectrum arise due to the interaction of the nuclear spins, whereby the spin polarization is transmitted through chemical bonds. The interaction strengths depend inter alia on the number of consecutive chemical bonds intervening between the two interacting spins and on the molecular conformation. The pairwise interaction of many spins in a molecule resulting in a complex spectrum poses a severe challenge to analyse the spectrum and hence the determination of magnitudes and signs of homo- and heteronuclear couplings. The problem is more severe in the analysis of 1H spectra than the spectra of most of the other nuclei due to the often very small chemical shift dispersion. As a consequence, the straightforward analysis and the accurate extraction of the coupling constants from the 1H spectrum of a complex spin system continues to remain a challenge, and often may be a formidable task. Over the years, the several pure shift-based one-dimensional and two-dimensional methodologies have been developed by workers in the field, which provide broadband homonuclear decoupling of proton spectra, removing the complexity but at the cost of the very informative scalar couplings. To circumvent this problem, several one-dimensional and two-dimensional NMR experiments have been developed for the determination of homonuclear and heteronuclear couplings (nJHX, where n = 1,2,3) while retaining the high resolution obtained by implementing pure shift strategies. This review attempts to summarize the extensive work reported by a large number of researchers over the years for the accurate determination of homo- and heteronuclear scalar couplings.

20.
World Neurosurg ; 177: 109-121, 2023 Jun 22.
Artículo en Inglés | MEDLINE | ID: mdl-37355169

RESUMEN

OBJECTIVE: This meta-analysis evaluated the impact of lumbar disk herniation and lumbar spinal stenosis (LSS) on axial back pain and the extent of improvement of axial and radicular pain following lumbar decompression and discectomy surgery in patients with low back pain (LBP). METHODS: A systematic search for published literature between January 2012 and January 2023 was made on PubMed, Google Scholar, and Cochrane library database on 31st January 2023. Original articles that included patients with lumbar disc herniation or LSS who underwent lumbar discectomy or lumbar decompression respectively were included in the study. RESULTS: A total of 71 studies including 16,770 patients with LBP undergoing lumbar discectomy or decompression surgery were included in the meta-analysis. The pooled standard mean difference between postoperative and preoperative: Visual Analog Scale scores for leg pain was -5.14 with 95% confidence interval (CI): -6.59 to -3.69 (P-value = 0) and for back pain was -2.90 with 95% CI: -3.79 to -2.01 (P value = 0), Numerical pain Rating Scale for leg pain was -1.64 with 95% CI: -1.97 to -1.30 (P-value<0.01) and for back pain was -1.58 with 95% CI: -1.84 to -1.32 (P-value <0.01), Oswerty Disability Index score was -4.76 with 95% CI: -6.22 to -3.29 (P-value = 0) and the Japanese Orthopaedic Association score was 3.45 with 95% CI: 0.02 to 6.88 (P value 0) at follow-up. CONCLUSIONS: This meta-analysis provides evidence that lumbar discectomy and decompression are effective in improving axial LBP in patients with lumbar disk herniation and LSS.

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