Browsing by Author "Pankaj Kumar"

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A family of multiply warped product semi-riemannian einstein metrics
(American Institute of Mathematical Sciences, 2020) Buddhadev Pal; Pankaj Kumar
In this paper, we characterize multiply warped product semi - Riemannian manifolds when the base is conformal to an n-dimensional pseudo-Euclidean space. We prove some conditions on warped product semi- Riemannian manifolds to be an Einstein manifold which is invariant under the action of an (n − 1)-dimensional translation group. After that we apply this result for the case of Ricci-flat multiply warped product space when the fibers are Ricci-flat. We also discuss the existence of infinitely many Ricci-flat multiply warped product spaces under the same action with null like vector. © 2020 American Institute of Mathematical Sciences. All rights reserved.
Almost Ricci-Bourguignon soliton on warped product space
(Elsevier Ltd, 2023) Santosh Kumar; Pankaj Kumar; Buddhadev Pal
The purpose of this article is to study the almost Ricci-Bourguignon soliton on warped product space. Some results for solenoidal and concurrent vector fields are obtained on warped product space with almost Ricci-Bourguignon soliton. We provide the relation between the warped manifold and its base manifold (fiber manifold) for an almost Ricci-Bourguignon soliton. We also generalize the Bochner formula in warped product space. Next, we study the Riemannian map whose total manifold admits an almost Ricci-Bourguignon soliton. We find the condition for a kernel of Riemannian map to become an almost Ricci-Bourguignon soliton. Moreover, we give an example for almost Ricci-Bourguignon soliton on warped product space. © 2023 Polish Scientific Publishers
An Integrated Statistical-Machine Learning Approach for Runoff Prediction
(MDPI, 2022) Abhinav Kumar Singh; Pankaj Kumar; Rawshan Ali; Nadhir Al-Ansari; Dinesh Kumar Vishwakarma; Kuldeep Singh Kushwaha; Kanhu Charan Panda; Atish Sagar; Ehsan Mirzania; Ahmed Elbeltagi; Alban Kuriqi; Salim Heddam
Nowadays, great attention has been attributed to the study of runoff and its fluctuation over space and time. There is a crucial need for a good soil and water management system to overcome the challenges of water scarcity and other natural adverse events like floods and landslides, among others. Rainfall–runoff (R-R) modeling is an appropriate approach for runoff prediction, making it possible to take preventive measures to avoid damage caused by natural hazards such as floods. In the present study, several data-driven models, namely, multiple linear regression (MLR), multiple adaptive regression splines (MARS), support vector machine (SVM), and random forest (RF), were used for rainfall–runoff prediction of the Gola watershed, located in the south-eastern part of the Uttarakhand. The rainfall–runoff model analysis was conducted using daily rainfall and runoff data for 12 years (2009 to 2020) of the Gola watershed. The first 80% of the complete data was used to train the model, and the remaining 20% was used for the testing period. The performance of the models was evaluated based on the coefficient of determination (R2), root mean square error (RMSE), Nash–Sutcliffe efficiency (NSE), and percent bias (PBAIS) indices. In addition to the numerical comparison, the models were evaluated. Their performances were evaluated based on graphical plotting, i.e., time-series line diagram, scatter plot, violin plot, relative error plot, and Taylor diagram (TD). The comparison results revealed that the four heuristic methods gave higher accuracy than the MLR model. Among the machine learning models, the RF (RMSE (m3/s), R2, NSE, and PBIAS (%) = 6.31, 0.96, 0.94, and −0.20 during the training period, respectively, and 5.53, 0.95, 0.92, and −0.20 during the testing period, respectively) surpassed the MARS, SVM, and the MLR models in forecasting daily runoff for all cases studied. The RF model outperformed in all four models’ training and testing periods. It can be summarized that the RF model is best-in-class and delivers a strong potential for the runoff prediction of the Gola watershed. © 2022 by the authors. Licensee MDPI, Basel, Switzerland.
An overview of human health risk from opium alkaloids and related pharmaceutical products pollution in aquatic ecosystems
(Elsevier, 2022) Sonam; Markandeya; Y. Shiv Shankar; Prashant Bhushan; Deepak Gautam; Pankaj Kumar; S.P. Shukla; Devendra Mohan
Fresh water is a valuable resource, but the increase in pollution of aquatic ecosystem is a matter of concern. Industries are rapidly budding in India, which discharge their effluents into the water bodies either directly or after treating partially. Pharmaceutical compounds are very important, but at the same time, release toxic contaminants in the environment. Pharmaceutical products impose huge effects on aquatic environment, resulting in acute and chronic damages, reproductive damage, behavioral changes, and inhibition of cell proliferation. The effluents produced from alkaloid processing industries is highly polluted having low pH, high COD, BOD5, sulfate, and TKN values, and a characteristic dark brown color. A number of physical as well as biological processes occurring in aquatic ecological unit may cause reduction of trace concentrations of pharmaceutical compounds. Treatment of wastewater generated from alkaloid processing is a challenging task because of the complex mixture of contaminants. Several methods for the treatment of these wastes, such as anaerobic and aerobic biological treatment, anaerobic treatment with membrane treatment, and aerobic treatment with catalytic wet air oxidation have been reported. Studies have also been conducted on physicochemical treatment in combination with activated sludge process. Membrane processes and Fenton oxidation have also been investigated as a post-treatment method. Membrane technologies are desirable for industrial wastewater treatment as no external addition of chemicals is required. © 2022 Elsevier Inc. All rights reserved.
An overview of textile dyes and their removal techniques: Indian perspective
(EM International, 2017) Karuna Singh; Pankaj Kumar; Rajani Srivastava
Textile industry discharge a huge amount of dye containing waste water which pollutes water, soil and also have adverse affect on human health, animal and plants. Imperfection of dyeing process, approximately 10-15% of the synthetic dyes is released into the industrial waste, causing serious environmental problems, flora and fauna of aquatic ecosystems as well as terrestrial ecosystem. It causes contamination of surface water, accumulation of toxic and carcinogenic substance in water. Removal of dyes from dye containing waste water must be done by either physico-chemical or biological methods. Biological methods are dominant over physico-chemical methods, and involve fungi, algae, actinomycetes and bacteria. Biological method is considered to be more efficient in terms of its long lasting benefits, and no negative impact on environment. For complete treatment of textile waste water, integration of physical, chemical and biological methods are necessary. Biological method is considered to be more efficient in terms of its long lasting benefits, and no negative impact on environment. Careful selection of microbial strain is an important suggestion and recommendation. © Copyright EM International.
Applications of UAVs in Plantation Health and Area Management in Malaysia
(Springer International Publishing, 2019) Ram Avtar; Stanley Anak Suab; Ali P. Yunus; Pankaj Kumar; Prashant K. Srivastava; Manish Ramaiah; Churchill Anak Juan
The scope of unmanned aerial vehicles (UAVs), also known as “drone technology, " is increasing, with various applications in the field of remote sensing and environment. UAVs not only provide high-resolution, real-time data, but also have different applications for end users. They have become an essential tool for land surveyors because traditional land survey methods are expensive and time-consuming, requiring trained professionals and many hours to measure a single plot of land. With the advancement of UAVs, we can significantly reduce the cost. In this study, we have collected UAV data in Malaysia to acquire information about the plantation management practices, as well as oil palm health assessment. Our results showed that multispectral data collected from a UAV-borne MicaSense RedEdge camera is useful for identifying physiological stress in mature oil palm plants, which clearly illustrates stunted tree crown with low value of normalized difference vegetation index (NDVI). © Springer Nature Switzerland AG 2020.
Characterization of Einstein Poisson warped product space
(Springer Science and Business Media Deutschland GmbH, 2022) Buddhadev Pal; Pankaj Kumar
In this article, we study the problem of the existence and nonexistence of warping function associated with constant scalar curvature on pseudo-Riemannian Poisson warped product space under the assumption that fiber space has constant scalar curvature. We characterize the warping function on Einstein Poisson warped space by taking the various dimensions of base space B (i.e; (1). dimB= 1 , (2). dimB≥ 2). © 2022, African Mathematical Union and Springer-Verlag GmbH Deutschland, ein Teil von Springer Nature.
Compact Einstein multiply warped product space with nonpositive scalar curvature
(World Scientific Publishing Co. Pte Ltd, 2019) Buddhadev Pal; Pankaj Kumar
In this paper, we characterize the Einstein multiply warped product space with nonpositive scalar curvature. As a result, it is shown that, if M is Einstein multiple-warped product spaces with compact base and nonpositive scalar curvature, then M is simply a Riemannian manifold. Next, we apply our result on Generalized Robertson-Walker space-time and Generalized Friedmann-Robertson-Walker space-time. © 2019 World Scientific Publishing Company.
Complexes of Zn(II) containing (o-)/(p-) carboxylato phenyl azo pentane 2,4-dione and 2,2′ bipyridine as ligands: Synthesis, characterization, colorimetric and fluorometric modulation in the presence of Ag+ ions
(Elsevier Ltd, 2013) Md. Amin Hasan; Niraj Kumari; Pankaj Kumar; Brajesh Pathak; Lallan Mishra
Azo-enol based ligands 2-[N′-(1-acetyl-2-oxo-propylidene) hydrazino]-benzoic acid (L1H2) and 4-[N′-(1 acetyl-2 oxo-propylidene)-hydrazino]-benzoic acid (L2H2) and their complexes [Zn(L1H)2(bpy)] (1) and [Zn(L 2H)2(bpy)] (2) (where bpy = 2, 2′-bipyridine) have been synthesized and characterized using elemental analyses, spectral (FT-IR, 1H NMR, 13C NMR, electronic absorption), emission and single-crystal X-ray diffraction studies. Complexes 1 and 2 display selective chromogenic and fluorogenic responses with Ag+ ions in the presence of several other metal ions. The binding is monitored separately using UV-Vis, fluorescence and 1H NMR spectral titrations. Job's plot supports a 1:2 stoichiometry for 1 and 2 with Ag+ ions. The pH dependent "on-off" switching of fluorescence from complexes 1 and 2 have been studied. The fluorescence intensity quenches (turns-off) upon addition of OH- ions, while it enhances (turns-on) in the presence of H + ions. © 2012 Elsevier Ltd. All rights reserved.
Comprehensive Drought Vulnerability Assessment in Northwestern Odisha: A Fuzzy Logic and Analytical Hierarchy Process Integration Approach
(Multidisciplinary Digital Publishing Institute (MDPI), 2023) Susanta Mahato; Gita Mandal; Barnali Kundu; Sonali Kundu; P.K. Joshi; Pankaj Kumar
Crafting a comprehensive strategy to mitigate the impact of droughts, a complex geo-hazard profoundly affecting socio-economic aspects, entails the creation of a drought vulnerability map as a primary step. This study harmonizes geospatial techniques and the Fuzzy Analytical Hierarchy Process (fuzzy AHP) to formulate such a map for northwestern Odisha, India. From six principal drought-induced vulnerability parameters, namely physical attributes, water demand and usage, agriculture, land use, groundwater and population/development, 22 sub-parameters were selected. Spatial layers were generated for each sub-parameter, followed by their fuzzification using a fuzzy membership approach. Subsequently, AHP was employed to establish parameter weights through pair-wise comparisons. By applying the weighted overlay method, drought vulnerability maps were generated, classifying regions into five vulnerability levels: very high, high, moderate, low, and very low. The outcomes indicate that roughly 33% of the area is classified as having high drought vulnerability. Validation of the approach using statistical metrics, including accuracy, root mean square error and mean absolute error, demonstrates its efficacy in gauging drought vulnerability, thereby aiding planners in devising effective drought mitigation strategies. © 2023 by the authors.
Correction to: Role of Neurokinin B in gametogenesis and steroidogenesis of freshwater catfish, Clarias batrachus (Cell and Tissue Research, (2023), 393, 2, (377-391), 10.1007/s00441-023-03788-0)
(Springer Science and Business Media Deutschland GmbH, 2023) Ankur Singh; Bechan Lal; Pankaj Kumar; Ishwar S. Parhar; Robert P. Millar
The authors regret that Fig. 7 is a repetition of Fig. 6 as presented in the original article. The original figure for Fig. 7 is shown below. The legend and description for the figure (Fig. 7) remain the same but with some minor change. (Figure presented.) Western blots analysis of StAR, 3β-HSD, 17β-HSD (a) and pERK1/2, ERK1/2, pAkt & Akt proteins (b) in the testicular explants of Clarias batrachus incubated with 5 nM and 50 nM of MRK-08 for 24 h in vitro. The expression is presented as an integrated relative density value (IRDV) as an arbitrary unit. All the values are expressed as Mean ± SEM (n = 3). Means with the same superscript do not differ from each other, while means with different superscripts are different from each other statistically at p < 0.05 (Duncan’s multiple range test). Superscripts *, ** and *** are used for StAR, while superscripts # & ### are used for 3β-HSD and superscripts, and for 17β-HSD, respectively (Fig. 7a). Superscripts *, ** and *** are used for p44 and superscripts #, ## & ### for p42 while superscripts and for pAkt (Fig. 7b) The original article has been corrected. © 2023, The Author(s), under exclusive licence to Springer-Verlag GmbH Germany, part of Springer Nature.
Correlation of nitric oxide (NO) activity and gonadal function in Japanese quail, Coturnix coturnix japonica following temporal phase relation of serotonergic and dopaminergic oscillations
(2008) Pankaj Kumar; Chandra Mohini Chaturvedi
Nitric oxide (NO), a highly reactive and short-lived radical, is considered to be an important trigger molecule for several physiological mechanisms including gonadotrophin releasing hormone (GnRH) secretion in mammals, although there is no such information in avian literature. On the other hand, specific temporal phase relation of circadian neural (serotonergic and dopaminergic) oscillations is reported to modulate reproductive activity in many avian species including Japanese quail. The present study was undertaken to investigate the correlation of NO activity and gonadal function of Japanese quail. In experiment I, the effect of serotonin and dopamine precursors, (5-hydroxytryptophan (5-HTP) and l-dihydroxyphenyalanine (l-DOPA) respectively; 5 mg per 100 g body weight) administered at intervals of 8 or 12 h over a period of 13 days, was studied on reproductive responses and NO activity. Measurements of body weight, cloacal gland size, testosterone concentration, spermatogenesis, nitrite-nitrate concentration in plasma, hypothalamus and testes, and NADPH-diaphorase (NADPH-d) activity in testes were made on the 2nd, 3rd, 6th and 11th days of treatment and 2nd and 30th day post-treatment. In experiment II, quail were divided into five groups including the control. One experimental group received 13 daily injections of 5-HTP and l-DOPA at intervals of 8 h along with 0.1 ml of normal saline administered orally (8-hr + Veh), while another group of 8-hr quail received NO donor (sodium nitroprusside (SNP), 5 mg per 100 g body weight) orally (8-hr + SNP). The third experimental group received 5-HTP and l-DOPA at intervals of 12 h along with normal saline (12-hr + Veh), while the fourth group of quail along with 5-HTP and l-DOPA at intervals of 12 h also received the NOS inhibitor (N-nitro-l-arginine methyl ester, l-NAME, 25 μg per 100 g body weight) intraperitoneally (12-hr + l-NAME) for 13 days. This experiment was terminated after 21 days of the treatment. Results indicate that 5-HTP and l-DOPA administered 8 h apart (8-hr) suppressed but if given 12 h apart (12-hr) stimulated the reproductive system and NO activity compared to the control. These effects were apparent on the 6th day of injections and were maintained 30 days following the termination of the treatment. A significant decrease in nitrite and nitrate concentration and NADPH-d activity in reproductively inhibited 8-hr group and an increase in reproductively stimulated 12-hr quail was also evident. In contrast, these activities were stimulated in 8-hr + SNP quail and were suppressed in 12-hr + l-NAME group quail. It is concluded that activity of the reproductive system and NO activity waxes and wanes simultaneously in Japanese quail. Moreover, experimental modulation of gonadal activity (following changes in the phase relation of serotonergic and dopaminergic activity) or NO activity (following the administration of NO modulator or inhibitor) affects each other maintaining a parallel relation between the two systems. Further, it is interesting to note that the gonado-stimulatory effect of SNP overpowers the gonado-inhibitory effects of the 8-hr time interval and inhibitory effects of l-NAME mask the stimulatory effects of 12-hr temporal relation of 5-HTP and l-DOPA administration. These findings strongly suggest that reproductive effects may be induced via changes in NO activity, however the exact mechanism by which NO drives gonadal axis needs to be ascertained. © 2007 Elsevier B.V. All rights reserved.
Does the Laxmi Ridge continue towards the Laccadive Ridge? New insights from an integrated geophysical study
(Elsevier Ltd, 2020) Akhil Mishra; Anil Kumar Chaubey; Shravan Kumar; Pitchika Vinay Kumar; Pankaj Kumar; Kanchan Mani Dubey
The Laxmi and Laccadive ridges are two major aseismic ridges in the NW Indian Ocean. Bathymetry, gravity and magnetic data and their derivatives are analyzed and modelled to assess interrelationship between both the ridges as well as to establish their crustal structure, nature and isostatic compensation. Boundaries of the Laxmi and Laccadive ridges are delineated by tilt derivative with constraints from available seismic-sections. Integrated gravity and magnetic models reveal that both the ridges have almost similar crustal layers and are underplated all along its length. Crustal models also depict that both the ridges are carpeted with flood basalt and heavily intruded. 3D coherence between mantle Bouguer anomaly and residual bathymetry reveals that the elastic plate thickness and subsurface to surface load ratio for both the ridges vary from 3 to 4 km and 0.7 to 0.8, respectively. Several characteristic similarities viz. crustal structure and nature, elastic plate thickness, magmatism have been observed for both the ridges. Seismic sections near the junction of the ridges suggest that the basement high corresponding to the Laxmi Ridge is further continued towards the Laccadive Ridge. In addition, the northwestern part of the Laccadive Ridge has NW-SE structural lineaments similar to that of the NW-SE segment of the Laxmi Ridge. Based on results of the present and previous studies, we infer that (i) the Laxmi Ridge is extended southeastward towards the Laccadive Ridge, (ii) both the ridges are continental slivers which are underplated as well as intruded and carpeted by volcanics, and (iii) both the ridges are locally compensated. © 2020 Elsevier Ltd
Effect of α-dl tocopherol acetate (antioxidant) enriched edible coating on the physicochemical, functional properties and shelf life of minimally processed carrots (Daucus carota subsp. sativus)
(Elsevier B.V., 2022) Divya Keshari; Abhishek Dutt Tripathi; Aparna Agarwal; Saloni Rai; Suresh Kumar Srivastava; Pankaj Kumar
The present study was carried out to investigate the effect of varying sodium alginate-based edible coating (1, 2, and 3 %, w/v) supplemented with α- tocopherol acetate (antioxidant) at different concentrations (0.5 and 1 % w/v) on minimally processed carrot slices during 15 d storage at 10 °C and 65 % relative humidity. Seven different formulations (T1- T7) comprising different alginate and antioxidant combination were tested for selecting the best formulation maintaining the physicochemical attributes, antioxidant potential, carotenoid content, and overall acceptability (microbial counts) of carrot slices. Treatment T4 (2% sodium alginate + 1% α-tocopherol acetate) served as the best formulation in maintaining the quality, acceptability, nutritive value of minimally processed carrots. The T4 treated carrot samples showed minimum variation in weight loss, TSS, pH, whiteness index, reducing sugar, ascorbic acid content, TPC, antioxidant activity, total carotenoids, total aerobic bacterial count and yeast and mold counts, respectively in comparison to other treatments during storage. The statistical analysis also confirmed the significant (p<0.05) variation in physicochemical properties, antioxidant potential, carotenoid content and microbial count in control samples than edible coating formulations during storage. © 2022
Effects of simulated hypo- and hyper-reproductive conditions on the characteristics of circadian rhythm in hypothalamic concentration of serotonin and dopamine and in plasma levels of thyroxine, triiodothyronine, and testosterone in Japanese quail, Coturnix coturnix japonica
(2009) Pankaj Kumar; Atanu Kumar Pati; Jag Mohan; Kochiganti Venkata Hanumat Sastry; Jagbir Singh Tyagi; Chandra Mohini Chaturvedi
In this study, hypo- and hyper-reproductive conditions, as measured by concentrations of plasma testosterone in male Japanese quail held on long days LD 16:8, were experimentally simulated with injections of 5-hydroxytryptophan (5-HTP) and L-dihydroxyphenylalanine, (L-DOPA) with 8 h and 12 h phase angle differences between them in intact and melatonin-treated birds. The effects of these treatments were assessed on the characteristics of the circadian rhythm in the hypothalamic concentration of serotonin (5-HT), dopamine (DA), and plasma levels of thyroxine (T4), triiodothyronine (T3), and testosterone (T). These rhythms were also studied in sham-operated (SO), pinealectomized (Px), vehicle- (Veh), and melatonin (Mel)-treated birds. On the basis of the circadian mesors of the testosterone rhythms, three distinct categories could be identified: category A (i.e., normal breeding concentrations of plasma testosterone), which includes control, sham-operated, and vehicle-treated groups; category A+ (i.e., concentrations of plasma testosterone higher than that found in normal breeding quail), which includes 12 h, 12 h+vehicle-treated, and Px quails; and category A- (concentrations of plasma testosterone lower than that found in normal breeding quail), which includes 8 h, melatonin-, and 12 h+melatonin-treated groups. It is evident that in normal and hypergonadal conditions (i.e., birds belonging to categories A and A+) the circadian rhythm in hypothalamic serotonin maintained a positive phase angle of about 16 h. In contrast, birds of category A- (i.e., in a hypogonadal condition) exhibited a negative phase angle of about 2 h. The present results clearly suggest that the internal phase relationship between the circadian rhythms in hypothalamic serotonin and dopamine might play a crucial role in strategizing and conferring a particular reproductive status to the birds. The role of circadian mechanisms involving circulating thyroid hormones in conferring reproductive status is completely ruled out, as no definite internal phase angle between these two hormonal rhythms was witnessed vis-a-vis different treatment groups. The testosterone peaks always occurred at the same time irrespective of breeding status of the bird, but with significant variation in its amplitude (high in hypergonadal and low in hypogonadal condition). It is suggested that administration of 5-HTP and L-DOPA at specific time interval and variation in pineal functions that modulate reproductive responses also alter the circadian pattern (acrophase and amplitude) of hypothalamic serotonin and dopamine, maintaining a specific phase relation between these cycles and breeding status. These findings strengthen our previous reports that a specific circadian phase relation of serotonergic and dopaminergic oscillations regulates reproduction. The present study strongly supports interdependence and specific relation of the two systems (gonadal activity and circadian pattern/phase relation of neural oscillation) in both natural and experimentally simulated conditions. Copyright © Informa Healthcare USA, Inc.
Einstein Poisson warped product space
(IOP Publishing Ltd, 2021) Buddhadev Pal; Pankaj Kumar
In this paper, we provide some results on Poisson manifold (M, Π) with contravariant Levi–Civita connection D associated to pair (Π, g). We introduce the notion of Einstein Poisson warped product space (M = B ×f F, Π, gf) (where Π = Π1 + Π2). Moreover, we show that if M is an Einstein Poisson warped product space with nonpositive scalar curvature and compact base B, J1 is a field endomorphism on T∗B satisfies J12 = I, then M is simply a Riemannian Poisson product. For a contravariant Lorentzian Poisson warped space (M = B ×f F, g, Π) (where B = I × R) one can determine contravariant Einstein equations and the cosmological constant Λ corresponding to the contravariant Einstein equation G = −Λg. Moreover, it is shown that Einstein equation G = −Λg, induces the contravariant Einstein equation GijF = −ΛFgijF with cosmological constant ΛF on fiber space (F, gF, ΠF). © 2021 IOP Publishing Ltd.
Einstein warped product spaces on Lie groups
(Universidad de la Frontera, 2022) Buddhadev Pal; Santosh Kumar; Pankaj Kumar
We consider a compact Lie group with bi-invariant metric, coming from the Killing form. In this paper, we study Einstein warped product space, M = M1 ×f1 M2 for the cases, (i) M1 is a Lie group (ii) M2 is a Lie group and (iii) both M1 and M2 are Lie groups. Moreover, we obtain the conditions for an Einstein warped product of Lie groups to become a simple product manifold. Then, we characterize the warping function for generalized Robertson-Walker spacetime, (M = I ×f1 G2, −dt2 + f12 g2) whose fiber G2, being semi-simple compact Lie group of dim G2 > 2, having bi-invariant metric, coming from the Killing form. © 2022 B. Pal et al. This open access article is licensed under a Creative Commons Attribution-NonCommercial 4.0 International License.
Emergence of non-albicans Candida among candidal vulvovaginitis cases and study of their potential virulence factors, from a tertiary care center, North India
(2013) Varsha Kumari; Tuhina Banerjee; Pankaj Kumar; Sulekha Pandey; Ragini Tilak
Purpose: The purpose of this study was to determine the prevalence of various Candida species and study some of their virulence factors among thevulvovaginal candidiasis(VVC)patients. Study Design and Settings: The study was conducted in a Tertiary Care University Hospital in North India. Materials and Methods: This study was carried out prospectively for a period of 1 year. High vaginal swabs (HVSs) were collected from women in childbearing age group attending the gynecology and obstetrics out-patient departments with the complaints suggestive of vulvovaginitis. Samples were plated on Sabouraud's dextrose agar slope. Candida spp. isolated was further speciated based on microscopy, biochemical tests and culture characteristics on special media. Virulence factors of these strains were determined by biofilm formation and phospholipase activity. Result: A total of 464 HVS from 232 patients with the complaints of vulvovaginitis were included in this study. Following laboratory workup, 71 specimens were positive for genus Candida (30.6%). Further speciation showed 32.4% as Candida albicans, 45.07% Candida parapsilosis and 22.53% of Candida glabrata. Biofilm production was shown by 50 candidal strains (70.4%) and phospholipase activity was given by 41 candidal strains (57.74%). Conclusion: Our study suggests increasing prevalence of non-albicans Candida among the VVC cases along with their virulence factors. Therefore, we recommend that microbiological investigation upto species level should be mandatory to determine the emergence of non-albicans Candida as a major cause of VVC.
Endocrine regulation of testosterone production by Leydig cells in the catfish, Clarias batrachus: Probable mediators of growth hormone
(Elsevier B.V., 2015) N. Dubey nee Pathak; Pankaj Kumar; Bechan Lal
Growth hormone (GH), in the recent past, has been recognized as a potent steroid stimulating hormone independent of gonadotropin (GtH). However, the mode and mechanism of its steroidogenic action in the testis is not yet elucidated, particularly in fish. The present study was designed to understand the mode and mechanism of steroidogenic action of growth hormone in testis of the catfish, Clarias batrachus through in vivo and in vitro Leydig cell culture studies using the signaling molecule inhibitors. Exogenous administration of GtH, GH and insulin to the male catfish increased testicular and circulating testosterone level. In vitro treatment of Leydig cells with these hormones also increased testosterone production. The steroidogenic action of GH appeared to be indirect and mediated through Leydig cell produced insulin-like growth factor I (IGF-I), as the treatments with actinomycin D, cycloheximide and anti-IGF-I abolished the GH-induced testosterone production by Leydig cells. The GH-induced stimulation in IGF-I production by the isolated Leydig cells further substantiates this notion. GH appears to employ cAMP/PKA and tyrosine kinase signaling pathways to induce IGF-I production, as the adenylyl cyclase inhibitor (SQ 22,536), cAMP-dependent protein kinase (PKA) blocker (H-89) and tyrosine kinase inhibitor (lavendustin A) abolished the GH-induced IGF-I production and in turn testosterone by the Leydig cells. This study suggests that GH exerts independent androgenic effect in the catfish testis indirectly through augmenting the Leydig cell production of IGF-I. © 2015 Elsevier B.V.
Endoscopic Third Ventriculostomy in Cases of Hydrocephalus: An Institutional Experience
(Georg Thieme Verlag, 2019) Prarthana Saxena; Sharad Pandey; Pankaj Kumar; Kaviraj Kausik; Shiv Lal Soni
Background With the recent advances in optical and mechanical instrumentation, endoscopic third ventriculostomy (ETV) has emerged as the procedure of choice for the treatment of hydrocephalus in selected patients. Objective: To study the role of ETV in therapeutic management of hydrocephalus in a tertiary care center. Materials and Methods The present study was conducted in the Department of Neurosurgery at Dr. Ram Manohar Lohia Hospital. Endoscopic third ventriculostomy was performed as a therapeutic procedure in patients diagnosed with hydrocephalus requiring surgical intervention and admitted from June 2017 to July 2018. ETV success was defined by resolution or improvement in clinical symptoms and ETV failure was considered in patients whose symptoms either deteriorated or did not improve from the baseline and required ventriculoperitoneal shunt. Results A total of 85 patients were included in this study who underwent the therapeutic ETV. In the present study, the overall ETV success rate was 75.2% (64/85). 86.7% cases of aqueductal stenosis, 74.4% cases of post meningitis (including tubercular meningitis) hydrocephalus, and 71% of posterior fossa tumors showed resolution or improvement in clinical symptoms. Conclusion ETV is an effective treatment modality for obstructive hydrocephalus and with better results in post meningitis hydrocephalus and post tubercular meningitis hydrocephalus. However, more extensive studies dedicated to ETV with a larger sample size are required to further study its efficacy in various etiologies. © 2019 Neurological Surgeons' Society of India.