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1.
Plant Biol (Stuttg) ; 23(5): 686-694, 2021 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-33768665

RESUMO

Reactive oxygen species (ROS) generation within a cell is a natural process of specific subcellular components involved in redox reactions. Within a plant cell, chloroplasts are one of the major sources of ROS generation. Plastid-generated ROS molecules include singlet oxygen (1 O2 ), superoxide radical (O2 - ), hydroxyl radical (OH• ) and hydrogen peroxide (H2 O2 ), which are produced mainly during photochemical reactions of photosynthesis and chlorophyll biosynthetic process. Under normal growth and developmental, generated ROS molecules act as a secondary messenger controlling several metabolic reactions; however, perturbed environmental conditions lead to multi-fold amplification of cellular ROS that eventually kill the target cell. To maintain homeostasis between production and scavenging of ROS, the cell has instituted several enzymatic and non-enzymatic antioxidant machineries to maintain ROS at a physiological level. Among chloroplastic ROS molecules, excess generation of singlet oxygen (1 O2 ) is highly deleterious to the cell metabolic functions and survival. Interestingly, within cellular antioxidant machinery, enzymes involved in detoxification of 1 O2 are lacking. Recent studies suggest that under optimal concentrations, 1 O2 acts as a signalling molecule and drives the cell to either the acclimation pathway or regulated cell death (RCD). Stress-induced RCD is a survival mechanism for the whole plant, while the involvement of chloroplasts and chloroplast-localized molecules that execute RCD are not well understood. In this review, we advocate for participation of chloroplasts-generated 1 O2 in signalling and RCD in plants.


Assuntos
Morte Celular Regulada , Oxigênio Singlete , Cloroplastos , Plastídeos , Espécies Reativas de Oxigênio
2.
J Appl Microbiol ; 128(4): 1128-1142, 2020 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-31821696

RESUMO

AIM: The aim of this study was to identify and characterize promising endophytes capable of enhancing the content of root alkaloids ajmalicine and serpentine in low alkaloid yielding genotype of Catharanthus roseus cultivar Prabal and the possible mechanisms involved. METHOD AND RESULT: Of the four strains isolated from alkaloid-rich genotype of C. roseus cultivar Dhawal, endophytic strains CATDLF5 (Curvularia sp.) and CATDLF6 (Choanephora infundibulifera) enhanced serpentine content by 211·7-337·6%, while CATDRF2 (Aspergillus japonicus) and CATDS5 (Pseudomonas sp.) increased the content of ajmalicine by 123·4-203·8% in cultivar Prabal. Upregulated expression of key genes, geraniol 10-hydroxylase, tryptophan decarboxylase and strictosidine synthase involved in terpenoid indole alkaloid (TIA) biosynthetic pathway was observed in endophyte inoculated plants. Upregulated Octadecanoid-derivative Responsive Catharanthus AP2/ERF domain transcription activators like ORCA3 while, and downregulation of transcriptional repressor, ZCTs (Cys2/His2-type zinc finger protein family) enhanced the expression of genes for secondary metabolite production in endophyte-inoculated plants. CONCLUSION: The present work concluded that the selected endophytes of C. roseus can enhance the ajmalicine and serpentine contents by modulating the expression of structural and regulatory genes of TIA biosynthetic pathway in root. SIGNIFICANCE AND IMPACT OF THE STUDY: Endophytes can play an important role to enhance in planta content of pharmaceutically important alkaloids in C. roseus and can therefore be useful in reducing the cost of production of important alkaloids.


Assuntos
Vias Biossintéticas/genética , Catharanthus/microbiologia , Endófitos/fisiologia , Alcaloides de Triptamina e Secologanina/metabolismo , Catharanthus/metabolismo , Endófitos/isolamento & purificação , Endófitos/metabolismo , Regulação da Expressão Gênica de Plantas , Proteínas de Plantas/genética , Raízes de Plantas/metabolismo , Raízes de Plantas/microbiologia , Fatores de Transcrição/genética
4.
J Appl Microbiol ; 122(5): 1286-1298, 2017 May.
Artigo em Inglês | MEDLINE | ID: mdl-28186676

RESUMO

AIMS: The aim of this study was to determine whether ACC (1-aminocyclopropane-1-carboxylic acid) deaminase-containing bacterial treatments could enhance the tolerance of poppy (Papaver somniferum L.) plants against biotic stress of downy mildew caused by Peronospora sp. METHODS AND RESULTS: Three different genotypes of P. somniferum, that is, Sampada, J-16 and I-14 were included in the experiment. The ACC deaminase-containing bacteria Pseudomonas putida (WPTe) reduced the downy mildew disease severity and significantly improved the growth and yield of P. somniferum plants. The chlorophyll content, photosynthetic rate, stomatal conductance and transpiration rate were modulated upon WPTe treatments in the poppy plants. We observed reduced synthesis of ethylene precursor (ACC) and abscisic acid (ABA), and enhanced production of indole acetic acid (IAA) in P. somniferum plants upon WPTe treatments. Moreover, WPTe treatment reduced proline and lipid peroxidation in plant leaves. CONCLUSION: These results highlight that the ACC deaminase-containing plant growth-promoting rhizobacteria (PGPR) enhance the tolerance of P. somniferum plant against downy mildew. SIGNIFICANCE AND IMPACT OF THE STUDY: ACC deaminase-containing PGPR may be used against phytopathogens which apart from protecting the plants from the disease could also be useful in reducing ethylene-induced damages in the event of abiotic stresses.


Assuntos
Carbono-Carbono Liases/metabolismo , Papaver/microbiologia , Peronospora/fisiologia , Doenças das Plantas/prevenção & controle , Pseudomonas putida/enzimologia , Aminoácidos Cíclicos , Carbono-Carbono Liases/genética , Clorofila/metabolismo , Papaver/crescimento & desenvolvimento , Papaver/metabolismo , Peronospora/genética , Fotossíntese , Doenças das Plantas/microbiologia , Folhas de Planta/crescimento & desenvolvimento , Folhas de Planta/metabolismo , Folhas de Planta/microbiologia , Pseudomonas putida/genética , Pseudomonas putida/isolamento & purificação , Microbiologia do Solo
5.
Dermatol Res Pract ; 2016: 3284937, 2016.
Artigo em Inglês | MEDLINE | ID: mdl-27143960

RESUMO

Micronutrients serve many important functions in our body and altered levels of heavy and trace metals are associated with cutaneous and systemic disorders. Vesicular palmoplantar eczema is an entity whose etiopathogenesis is a mystery. In this prospective case-noncase study blood levels of Zinc and Cadmium in 37 patients of chronic vesiculobullous hand dermatitis were estimated and compared with 40 noncases with similar age and gender distributions. Low serum Zinc levels were found in patients as compared to noncases. The mean difference of serum Zinc between the case and noncase groups was 27.26; the mean value of serum Zinc between the two groups was statistically significant (p < 0.0001). However, elevated Cadmium levels were detected in only 5 patients and in none of the noncases. The mean concentration of serum Cadmium was 2.32 ± 0.38 µg/dL, with a range of 1.90-2.80 µg/dL for the five cases in whom Cadmium was detected. Various toxic and trace metals can interact by influencing each other's absorption, retention, distribution, and bioavailability in the body. The clinical significance of this finding lies in the possible beneficial role of Zinc supplementation in the therapy of chronic vesiculobullous hand dermatitis.

6.
Indian J Cancer ; 51(3): 293-302, 2014.
Artigo em Inglês | MEDLINE | ID: mdl-25494125

RESUMO

Cutaneous T-cell lymphomas (CTCLs) comprise a heterogeneous group of lymphoproliferative disorders characterized by the proliferation of skin-homing post-thymic T-cells. It is the second most common extranodal non-Hodgekin's lymphoma. Many variants of mycosis fungoides and CTCLs are known to date, differing in clinical, histological, and immunophenotypic characteristics. Oral involvement has also been reported rarely in CTCLs. Treatment depends on the disease stage or the type of variant. New insights into the disease and the number of emerging novel therapeutic options have made it an interesting area for dermatologists and medical oncologists.

7.
Indian J Lepr ; 86(3): 111-6, 2014.
Artigo em Inglês | MEDLINE | ID: mdl-26118223

RESUMO

Leprosy is not a disease of modern civilization and industrialization, but its origin is as old as 4600 BC. Although the cure of leprosy is possible by MDT, there are certain misbelieves in the mind of leprosy patients leads to delay in disease reporting. Wandering of the patient from one healer to another healer also one of the cause that delays the start of MDT. It is known fact that the delayed response in getting medical treatment for leprosy causes permanent physical deformities in the patient. This study is aimed to identify the treatment behavior of leprosy patients on time scale. A total of 251 study subjects were selected randomly attending the Skin & VD OPD of S S Hospital of IMS, BHU, Varanasi. Questions related to treatment behavior on time scale were administered to leprosy patients aged 15 years or above by the interviewer himself. Time gap to start the initial treatment was significantly less in MB cases (5.3 months) as compared to PB cases (7.2 months). MB cases wasted significantly more time with allopathic treatment other than MDT. Urban patients (1.3 months) wasted more time with homeopathy than the rural patients (0.9 months). More than half the cases (51.4%) went for the treatment within three months of noticing symptoms of leprosy. There is a considerable delay in starting the MDT after noticing the first symptom of leprosy. As early as possible, measures to start the proper treatment i.e. MDT should be taken to avoid permanent disability due to leprosy.


Assuntos
Hansenostáticos/uso terapêutico , Hanseníase/tratamento farmacológico , Hanseníase/psicologia , Aceitação pelo Paciente de Cuidados de Saúde , Adolescente , Adulto , Estudos Transversais , Quimioterapia Combinada , Feminino , Humanos , Índia , Masculino , Adulto Jovem
8.
Indian J Dermatol ; 57(1): 12-4, 2012 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-22470201

RESUMO

BACKGROUND: Vitiligo is an acquired depigmenting disorder characterized by the loss of functional melanocytes from the epidermis. Although the etiology of vitiligo is unknown, over the last few years, substantial data from clinical research has greatly supported the 'Autoimmune theory' and this is supported by the frequent association of vitiligo with disorders that have an autoimmune origin, including Hashimoto's thyroiditis, Graves disease, type 1 insulin-dependent diabetes mellitus, and Addison's disease. As cytokines are important mediators of immunity, there is evidence to suggest that they play a major role in the pathogenesis of autoimmune diseases. AIM: Keeping this in view we have assayed sera for cytokine IL-6, IL-2, Tumor necrosis factor (TNF)-α, and IFNγ in 80 cases of vitiligo and compared it with healthy subjects, in order to find out whether they play a role in the pathogenesis of vitiligo or not. MATERIALS AND METHODS: Serum IL-6, IL-2, TNF-α, and IFNγ were done by the indirect enzyme linked immunosorbent assay (ELISA). RESULTS: The mean serum IL-6 and IL-2 levels in the patient group were significantly higher when compared with those of the normal controls. The mean serum IFNγ level in patients with vitiligo was significantly lower than that in the control group. There was no significant difference in the serum level of TNF-α between vitiligo and healthy controls. CONCLUSION: An increase in the production of proinflammatory cytokines such as IL-6 and IL-2 in vitiligo patients may play an important role in melanocytic cytotoxicity. Thus, we speculate that the cytokine production of epidermal microenvironment may be involved in vitiligo.

9.
Phys Chem Chem Phys ; 14(5): 1796-805, 2012 Feb 07.
Artigo em Inglês | MEDLINE | ID: mdl-22167090

RESUMO

We present femto-to-millisecond studies of the photodynamics of seven types of indole-based squaraine molecules (SQs) in solvents of different H-bonding ability and viscosity. These SQs can be classified into two families: SQs with two carboxylic groups in the side indole groups (symmetrical SQs) and with only one carboxylic group (asymmetrical SQs). Steady-state absorption and fluorescence techniques show narrow absorption and emission bands, with a small Stokes shift (about 300 cm(-1)). The femtosecond transient absorption spectra give a very short (∼100 fs) dynamics (assigned to IVR) and the associated spectra show two excited species assigned to two stereoisomers. A trans-cis photoisomerization occurs in a very fast time through a conical intersection. Pico-to-nanosecond emission experiments also reveal the presence of two fluorescing trans stereoisomers whose lifetimes show similar sensitivities to the nature of solvent. For example, lifetimes of 1.72, 0.46 and 0.29 ns were determined for the trans photoisomer of the SQ 41 in triacetin, dichloromethane and acetonitrile, respectively, reflecting the short decay of the S(1) state in highly polar and low viscous solvents. Flash photolysis experiments gave the transient absorption signals of the cis photoisomer that is formed after the twisting process at S(1). The cis-to-trans photoisomerization at the ground state happens in the µs time scale (1-4 µs), and it depends on the H-bonding ability and viscosity of the solvent. Thus, combining fs-ns and ns-µs experiments suggests that in the conical intersection region, only a small fraction of the twisted trans isomers are converted to the cis ones in the excited states. These results bring detailed and global insight into the large time window photodynamics of this family of SQs in solution.

10.
Int J Obstet Anesth ; 18(1): 85-8, 2009 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-19111230

RESUMO

Anaphylactoid reaction to Syntocinon is rare, but has been described in the literature. The reactions described include patchy erythema, hypotension, bronchospasm and oxygen desaturation, but pulseless electrical activity following Syntocinon has not been reported. We present the case of a 34-year-old primigravida with essential hypertension, gestational diabetes and hypothyroidism with a twin pregnancy following in vitro fertilization. During elective caesarean delivery she developed a severe anaphylactic reaction to Syntocinon leading to pulseless electrical activity.


Assuntos
Anafilaxia/induzido quimicamente , Ocitócicos/efeitos adversos , Ocitocina/efeitos adversos , Complicações na Gravidez/induzido quimicamente , Adulto , Anafilaxia/complicações , Anafilaxia/tratamento farmacológico , Raquianestesia/métodos , Eletrocardiografia , Feminino , Humanos , Hipertensão/complicações , Hipotireoidismo/complicações , Palpação/métodos , Gravidez , Complicações na Gravidez/tratamento farmacológico , Gravidez Múltipla , Gêmeos
11.
Med J Armed Forces India ; 63(1): 23-5, 2007 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-27407931

RESUMO

BACKGROUND: This study was conducted to assess and increase the level of awareness of occupational hazards among the dental surgeons of Indian Navy. METHODS: The data was obtained using a self-administrated questionnaire from 17 serving dental surgeons that included questions on personal data, awareness of occupational hazards, safety measures practiced and experience of occupational hazard while in practice. RESULTS: All the respondents were aware of the occupational hazards at workplace and had been vaccinated against Hepatitis B infection. 82.3% had regular exposure to dental amalgam. Backache was the commonest hazard in 70.59% members of the study. CONCLUSION: This study shows that although there appears to be a high level of awareness of exposure to occupational hazards among the dental surgeons of the Indian Navy, the practical steps to prevent them needs to be reinforced. Increased awareness must be created about the dangers of chronic mercury poisoning, its prevention, the importance of regular monitoring of blood mercury levels and the mercury vapour levels in the clinic.

12.
Med J Armed Forces India ; 61(2): 171-3, 2005 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-27407742

RESUMO

Orthodontic therapies involving no compliance from patients are the mainstay of modern orthodontics. Class II division 1 malocclusions constitute the bulk of cases requiring extractions to facilitate space gain to correct it. The Pendulum Appliance is an effective and reliable method for distalizing maxillary molars. Its major advantages are minimal dependence on patient compliance, ease of fabrication, one-time activation, adjustment of the springs if necessary to correct minor transverse and vertical molar positions and patient-acceptance. Simple laboratory procedure for fabrication and relatively low cost make it an excellent appliance to be incorporated into regular practice.

13.
J Wound Care ; 13(5): 177-9, 2004 May.
Artigo em Inglês | MEDLINE | ID: mdl-15160570

RESUMO

OBJECTIVE: To investigate the effect of topical placental extract in the treatment of non-healing wounds. METHOD: One hundred patients attending the wound clinic at University Hospital, Varanasi, India, with wounds of more than six weeks' duration were recruited. Fifty patients were treated with placental extract, and 50 were controls. Wound biopsy and swab culture and sensitivity were performed and the area surrounding the wound was X-rayed. Wound size was measured and the rate of epithelialisation assessed at weekly follow-ups. In nine cases biopsies were repeated after two weeks of treatment and sent for histopathological examination, including angiogenesis. RESULTS: Thirty patients dropped out, leaving 40 cases in the treatment group and 30 in the control group. Over an eight-week period, 27 patients (67.5%) in the treatment group showed more than 50% epithelialisation, compared with only seven patients (23.3%) in the control group. CONCLUSION: Placental extract has a beneficial role to play as a topical agent in the management of chronic non-healing wounds.


Assuntos
Extratos Placentários/uso terapêutico , Úlcera/terapia , Adulto , Doença Crônica , Feminino , Humanos , Masculino , Úlcera/patologia
14.
Int J Low Extrem Wounds ; 2(3): 164-7, 2003 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-15866841

RESUMO

Plantar ulcers occur in patients with Hansen's disease not because of the disease but because of its neuropathic effects on the skin over the feet. This enhances the risk of trauma to patients' feet, leading to the development of ulcers. This short article reviews the current management of leprosy on the basis of World Health Organization guidelines and the complexities of plantar ulceration in such patients. A guide to its management and prevention is also discussed.

16.
Med J Armed Forces India ; 57(3): 247-9, 2001 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-27365610
17.
J Am Acad Dermatol ; 43(1 Pt 1): 61-5, 2000 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-10863225

RESUMO

BACKGROUND: Topical corticosteroids, commonly used for psoriasis, show diminished response on continuous use. OBJECTIVE: We tested efficacy of topical corticosteroid and calcipotriene used on alternate weeks versus daily corticosteroid in patients with psoriasis. METHODS: In a randomized, observer-blind design, the experimental group of 25 patients with stable plaque psoriasis received augmented betamethasone dipropionate 0.05% cream once daily in the first and third weeks and calcipotriene 0.005% ointment twice daily in the second and fourth weeks. The control group of 27 patients received augmented betamethasone once daily for 4 weeks. RESULTS: The experimental regimen was more effective than the control regimen as evidenced by (1) more patients with at least a 90% reduction in Psoriasis Area and Severity Index (PASI) score (difference 49.5%, 95% confidence interval [CI], 26.1%-72.9%, P <. 001), (2) lower PASI after 2 weeks (P < or =.04), and (3) greater percentage reduction in PASI after 2 and 4 weeks (difference 23.1% [CI, 11.1%-35.1%] and 46.4% [28.9%-63.8%], respectively; P <.001). The study had power of 93.7%. No patient had skin irritation. CONCLUSION: Use of augmented betamethasone and calcipotriene on alternate weeks is more effective than daily corticosteroid and represents a novel strategy for treating psoriasis.


Assuntos
Calcitriol/análogos & derivados , Fármacos Dermatológicos/administração & dosagem , Psoríase/tratamento farmacológico , Administração Tópica , Adulto , Anti-Inflamatórios/administração & dosagem , Betametasona/administração & dosagem , Betametasona/análogos & derivados , Calcitriol/administração & dosagem , Feminino , Glucocorticoides , Humanos , Masculino , Pessoa de Meia-Idade , Método Simples-Cego , Resultado do Tratamento
18.
J Wound Care ; 9(5): 247-50, 2000 May.
Artigo em Inglês | MEDLINE | ID: mdl-11933336

RESUMO

One hundred patients with non-healing wounds of more than six weeks' duration were studied for clinico-epidemiological factors and their correlation with healing time. The majority of subjects were aged 30-59 years; those aged 50 and over had significantly delayed healing. Most of the subjects were farmers and physical labourers. Leprosy was the most common cause of non-healing wounds, followed by diabetes, trauma and venous ulcers; the lower limbs were the most common site of involvement. Diabetic wounds were more common in those aged 40 years and above. Diabetic wounds were slower to heal than others. The time to healing was calculated from the day subjects received treatment advice at the wound clinic. Seventy-five of the study group were included for calculation of healing time. The others were lost to follow-up or excluded for other reasons.


Assuntos
Úlcera Cutânea/epidemiologia , Pele/lesões , Ferimentos e Lesões/epidemiologia , Adolescente , Adulto , Idoso , Criança , Doença Crônica , Feminino , Hospitais , Humanos , Índia , Hanseníase/epidemiologia , Masculino , Pessoa de Meia-Idade
19.
Artigo em Inglês | MEDLINE | ID: mdl-20921779

RESUMO

A case of recurrent pityriasis rosea in a 25-year old man is reported. He had his first attack 4 years ago and new outbreaks followed every year in winter with last 2 episodes occurring in the same year. All investigations were normal and no explanation for recurrences was found.

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