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1.
Bioprocess Biosyst Eng ; 36(1): 57-68, 2013 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-22678130

RESUMO

This study aimed to assess the variability in respect of titer and properties of xylanase from Trichoderma reesei SAF3 under both solid-state and submerged fermentation. SSF was initially optimized with different agro-residues and among them wheat bran was found to be the best substrate that favored maximum xylanase production of 219 U (gws)(-1) at 96 h of incubation. The mycelial stage of the fungi and intracellular accumulation of Ca(++) and Mg(++) induced maximum enzyme synthesis. Inoculum level of 10 × 10(6) spores 5 g(-1) of dry solid substrate and water activity of 0.6 were found to be optimum for xylanase production under SSF. Further optimization was made using a Box-Behnken design under response surface methodology. The optimal cultivation conditions predicted from canonical analysis of this model were incubation time (A) = 96-99 h, inoculum concentration (B) = 10 × 10(6) spores 5 g(-1) of dry substrate, solid substrate concentration (C) = 10-12 g flask(-1), initial moisture level (D) = 10 mL flask(-1) (equivalent to a(w) = 0.55) and the level of xylanase was 299.7 U (gws)(-1). Subsequent verification of these levels agreed (97 % similar) with model predictions. Maximum amount of xylanase was recovered with water (6:1, v/w) and under shaking condition (125 rpm). Purified xylanase from SSF showed better stability in salt and pH, was catalytically and thermodynamically more efficient over enzyme from SmF, though molecular weight of both enzymes was identical (53.8 kDa).


Assuntos
Reatores Biológicos/microbiologia , Endo-1,4-beta-Xilanases/biossíntese , Modelos Biológicos , Trichoderma/enzimologia , Triticum/microbiologia , Simulação por Computador , Endo-1,4-beta-Xilanases/isolamento & purificação
2.
Artigo em Inglês | MEDLINE | ID: mdl-37807029

RESUMO

The hydrogen industry has garnered substantial attention as a pivotal solution in addressing the intricate challenges of energy transition and achieving decarbonization across diverse sectors. The efficacy of deploying hydrogen technologies hinges upon the availability of robust financing mechanisms that can adequately support the dynamic demands and intricate supply chain intricacies inherent in the hydrogen sector. This comprehensive study is underpinned by a rigorous and systematic review of prior research on the hydrogen economy, leveraging authoritative databases including Web of Science, Scopus, and a range of consultancy-based reports. The study meticulously assesses the escalating interest in hydrogen as a paramount clean energy alternative, emphasizing its significance in propelling the multifaceted development and expansion of hydrogen supply chain dynamics. Furthermore, this research critically scrutinizes the intricate financial facets of the hydrogen sector, with a specific focus on delineating the drivers of demand and unraveling the complexities interwoven within the supply chain. Building upon this analysis, the study offers a forward-looking perspective on hydrogen financing, which considers emerging technologies, evolving policy landscapes, and dynamic market trends. In the face of existing global constraints within the hydrogen supply chain, innovative financing mechanisms such as green bonds, project financing underwritten by risk guarantees through public-private partnership paradigms, venture capital-equity models, and carbon pricing mechanisms emerge as indispensable tools poised to address these challenges effectively.

3.
Clean Technol Environ Policy ; 24(5): 1337-1358, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35069066

RESUMO

The Indian renewable energy sector has grown at a compounded annual growth rate of 15.51% in the last five years, where wind growth is about 8%. The Indian government has been adopting changes to create a safe, cheap, and sustainable energy system to fuel vigorous economic growth. The government has made significant efforts in ensuring universal access to energy, giving power to its residents. It is implementing a large-scale deployment of renewable energy, particularly solar and wind. This paper examines the country's wind sector in-depth, including the government policy, financial incentives, and accomplishments. The study goes on to discuss the prospects and problems of the wind sector, as well as solutions to overcome them to reach the estimated target of 140-150 GW by 2030. Wind power growth in the country has weakened in the last few years which may hamper the country's ambitious renewable energy targets. Wind industry is facing several hindrances ranging from discontinuation of incentives, land acquisition, DISCOM's poor health, change in bidding scheme, old wind sites, etc. Certain steps, such as repowering outdated wind farms, giving generation-based incentives, tax concessions, reassessing the country's wind potential, and constructing competitive renewable energy zones could aid in reviving the wind energy sector.

4.
Saudi J Kidney Dis Transpl ; 29(4): 879-888, 2018.
Artigo em Inglês | MEDLINE | ID: mdl-30152425

RESUMO

Oxygen is very important to the existence of life. Oxygen deficiency, defined as hypoxia, elicits adaptive responses in cells and tissues. Lower oxygen concentration can cause the alteration of renal function, affects the maintenance of a balance of the body fluids, electrolytes, pH, and blood pressure homeostasis. Impaired fluid regulation could, in addition, contribute to the precipitation of pulmonary edema and exacerbate hypoxemia which may accelerate the progression of chronic kidney disease. In this context, the present study attempted to evaluate the association of renal injury and oxidative stress at different atmospheric pressures (1829, 3657, and 5486 m). Limited fecal analysis of experimental animals was also done to evaluate the impact of hypobaric hypoxia on the composition of dominant gastrointestinal microbiota. The study was performed on 24 male Wister strain rats and divided into four groups (C, HA-I, HA-II, and HA-III), and exposure was carried out for seven days period. In hypoxic exposure rats, plasma urea, creatinine, electrolytes and malonaldehyde level elevated and catalase and superoxide dismutase level diminished significantly compared to the controls. Increase in blood uremia profile, toxicity markers, and lipid peroxidation marker enzymes indicated that hypoxia causes renal failure. Histological structures of the kidney of group HA-II and HA-III animals showed severe disorganization of glomerulus and dilation of renal tubules. These results indicate nephrotoxicity or acute renal failure can occur at hypobaric hypoxia and it also affected the gut microbial population. This alteration was observed significantly above 3000 m.


Assuntos
Injúria Renal Aguda , Microbioma Gastrointestinal/fisiologia , Hipóxia , Injúria Renal Aguda/metabolismo , Injúria Renal Aguda/fisiopatologia , Animais , Pressão Atmosférica , Nitrogênio da Ureia Sanguínea , Creatinina/sangue , Hipóxia/metabolismo , Hipóxia/fisiopatologia , Masculino , Malondialdeído/sangue , Estresse Oxidativo/fisiologia , Oxigênio/sangue , Oxigênio/metabolismo , Ratos , Ratos Wistar
5.
J Contemp Brachytherapy ; 10(4): 321-336, 2018 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-30237816

RESUMO

PURPOSE: This study analyzes clinical consequences and dosimetric variations after imperfect brachytherapy insertions. It examines treatment decisions after such insertions in patients having difficult anatomy, which leads to good subsequent insertions with acceptable dose volume parameters. MATERIAL AND METHODS: We reviewed images of all insertions performed during last one year and sorted faulty ones out. Clinical outcome was assessed, analyzing original treatment records. Repeat three-dimensional planning using identical dose-optimization-technique compared their dosimetry. Statistical analysis using SPSS®-Statistics-software included Fisher's-exact-test to analyze predisposing factors for faulty insertions and predictive factors for subsequent satisfactory insertion. Friedman test was used to compare dose-volume-effects of normalization. RESULTS: Eighteen of 292 brachytherapy plans revealed imperfect insertions, including thirteen perforations (4.5%). Lack of pre-planning, obstructing mass, narrow vagina, acute anteversion of uterus, and multi-parity were significant (p ≤ 0.05) predisposing factors for atypical insertions. Satisfactory optimization was possible after correcting acute anteflexion or positioning tandem in retroverted direction in uncorrectable retroverted uterus. Dose normalization at point A shifted optimized dose from contoured volume to point of normalization, often undesirably. This difference, however, was statistically not significant (p = 0.121). In patients having obstructing mass, subsequent insertions were perfect, and dose volume parameters were acceptable only when full prescribed dose was delivered to at least 60% volume of the mass after a faulty insertion (p < 0.001). CONCLUSIONS: Pre-planning by imaging is suggested in all cases of brachytherapy. Insertion of adequate length of tandem aligned to uterine axis is warranted for adequate tumor coverage. Whenever detected, acute anteflexion and mobile retroversion should be corrected. Tandem inserted in retroverted direction in uncorrectable retroverted uterus generates acceptable dose volume parameters. In cases with obstructive cervical mass, good subsequent insertion is possible with acceptable dose volume parameters, if planned dose can be delivered to its 60% volume.

6.
J Contemp Brachytherapy ; 9(5): 431-445, 2017 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-29204164

RESUMO

PURPOSE: This study is intended to compare dose-volume parameters evaluated using different forward planning- optimization techniques, involving two applicator systems in intracavitary brachytherapy for cervical cancer. It looks for the best applicator-optimization combination to fulfill recommended dose-volume objectives in different high-dose-rate (HDR) fractionation schedules. MATERIAL AND METHODS: We used tandem-ring and Fletcher-style tandem-ovoid applicator in same patients in two fractions of brachytherapy. Six plans were generated for each patient utilizing 3 forward optimization techniques for each applicator used: equal dwell weight/times ('no optimization'), 'manual dwell weight/times', and 'graphical'. Plans were normalized to left point A and dose of 8 Gy was prescribed. Dose volume and dose point parameters were compared. RESULTS: Without graphical optimization, maximum width and thickness of volume enclosed by 100% isodose line, dose to 90%, and 100% of clinical target volume (CTV); minimum, maximum, median, and average dose to both rectum and bladder are significantly higher with Fletcher applicator. Even if it is done, dose to both points B, minimum dose to CTV, and treatment time; dose to 2 cc (D2cc) rectum and rectal point etc.; D2cc, minimum, maximum, median, and average dose to sigmoid colon; D2cc of bladder remain significantly higher with this applicator. Dose to bladder point is similar (p > 0.05) between two applicators, after all optimization techniques. CONCLUSIONS: Fletcher applicator generates higher dose to both CTV and organs at risk (2 cc volumes) after all optimization techniques. Dose restriction to rectum is possible using graphical optimization only during selected HDR fractionation schedules. Bladder always receives dose higher than recommended, and 2 cc sigmoid colon always gets permissible dose. Contrarily, graphical optimization with ring applicators fulfills all dose volume objectives in all HDR fractionations practiced.

7.
Case Rep Dent ; 2016: 2197450, 2016.
Artigo em Inglês | MEDLINE | ID: mdl-26881145

RESUMO

Certain dipteran flies larvae causing invasion of the tissues and organs of the humans or other vertebrates are called as myiasis, which feed on hosts dead or living tissues. It is well documented in the skin and hot climate regions; underdeveloped countries are affected more commonly. Oral cavity is affected rarely and it can be secondary to serious medical conditions. Poor oral hygiene, alcoholism, senility, or suppurating lesions can be associated with the oral myiasis. Inflammatory and allergic reactions are the commonest clinical manifestations of the disease. In the present case, gingiva of maxillary anterior region was affected by larval infection in a 13-year-old mentally retarded patient.

8.
J Int Oral Health ; 6(6): 18-21, 2014.
Artigo em Inglês | MEDLINE | ID: mdl-25628477

RESUMO

BACKGROUND: Oral and maxillofacial surgeons are concern about the intraoperative bleeding because blood supply to face is very generous. Increased blood loss may lead to the need for transfusion of blood and blood products and hence patients are exposed to the risks associated with it. Hence, this study was undertaken to compare whether there is any significant difference in blood loss, surgical field and duration of surgery in patients undergoing maxillofacial surgeries with and without hypotensive anesthesia. MATERIALS AND METHODS: The study was conducted on patients undergoing various maxillofacial surgeries. The patients were randomly divided into two groups, the study group and the control group. In the study group patients, induced hypotension was used in order to maintain systolic pressure of 80-90 mm Hg. In the control group patients, normotensive anesthesia was used. Estimation of blood loss (EBS), quality of the surgical field and duration of surgery was calculated for both groups in three types of surgical procedures. Statistical analysis was performed by using two-tailed Pearson correlation test. RESULTS: EBS was found to be significantly less in all the surgical procedures carried out under hypotensive anesthesia (P < 0.05). The quality of the surgical field was better in cases with induced hypotension, but there was no significant difference in duration of the procedures with and without induced hypotension. CONCLUSION: Our study shows that hypotensive anesthesia can be safely used in almost all maxillofacial surgical procedures with reduced blood loss and improved surgical field.

9.
J Int Oral Health ; 6(1): 20-6, 2014 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-24653598

RESUMO

BACKGROUND: Mandibular fractures are treated surgically by either rigid or semi-rigid fixation, two techniques that reflect almost opposite concept of craniomaxillofacial osteosynthesis. The shortcomings of these fixations led to the development of 3 dimensional (3D) miniplates. This study was designed with the aim of evaluating the efficiency of 3D miniplate over Champys miniplate in anterior mandibular fractures. MATERIALS & METHODS: This study was done in 40 patients with anterior mandibular fractures. Group I consisting of 20 patients in whom 3D plates were used for fixation while in Group II consisting of other 20 patients, 4 holes straight plates were used. The efficacy of 3D miniplate over Champy's miniplate was evaluated in terms of operating time, average pain, post operative infection, occlusion, wound dehiscence, post operative mobility and neurological deficit. RESULTS: The mean operation time for Group II was more compared to Group I (statistically significant).There was significantly greater pain on day of surgery and at 2nd week for Group II patients but there was no significant difference between the two groups at 4th week. The post operative infection, occlusal disturbance, wound dehiscence, post operative mobility at facture site, neurological deficit was statistically insignificant (chi square test). CONCLUSION: The results of this study suggest that fixation of anterior mandibular fractures with 3D plates provides three dimensional stability and carries low morbidity and infection rates. The only probable limitation of these 3D plates may be excessive implant material, but they seem to be easy alternative to champys miniplate. How to cite the article: Barde DH, Mudhol A, Ali FM, Madan RS, Kar S, Ustaad F. Efficacy of 3-Dimensional plates over Champys miniplates in mandibular anterior fractures. J Int Oral Health 2014;6(1):20-6.

10.
J Contemp Brachytherapy ; 5(1): 42-4, 2013 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-23634154

RESUMO

We report a unique case of successfully performed intraluminal brachytherapy for low volume urethral mucosal recurrence of transitional cell carcinoma urinary bladder, initially treated by transurethral resection of bladder tumor, followed by radical cystectomy. Since the patient was unwilling to undergo any other operational interventions, intraluminal brachytherapy of urethra was attempted. Fluroscopy guided intraluminal HDR brachytherapy using Lumencath(®) catheter under local anesthesia, and remote afterloading system (Nucletron, an Elekta company, Elekta AB, Stockholm, Sweden) was performed. A fraction dose of 7 Gy in seven weekly fractions was prescribed at 0.5 cm from the single applicator. The result was promising in terms of local control and symptomatic relief. Therefore, intraluminal brachytherapy in low volume superficial local disease in urethra may play a potential role, and should be applied when repeated surgery is not feasible due to technical or medical reasons.

11.
J Neurosci Rural Pract ; 3(2): 152-7, 2012 May.
Artigo em Inglês | MEDLINE | ID: mdl-22865967

RESUMO

BACKGROUND: Trigeminal neuralgia is a commonly diagnosed neurosensory disease of head, neck and face region, involving 5(th) cranial nerve. Carbamazepine is the first line drug if there is decrease in efficacy or tolerability of medication, surgery needs to be considered. Factors such as pain relief, recurrence rates, morbidity and mortality rates should be taken in to account while considering which technique to use. Peripheral neurectomy is a safe and effective procedure for elderly patients and in rural and remote centers where neurosurgical facilities are not available. It is also effective in those patients who are reluctant for major neurosurgical procedures. Although loss of sensation along the branches of trigeminal nerve and recurrence rate are associated with peripheral neurectomy, we consider it as the safe and effective procedure in rural practice, which can be done under local anesthesia. AIMS: The aim of this prospective study is to evaluate the long term efficacy of peripheral neurectomy with and without the placement of stainless steel screws in the foramina and to calculate the mean remission period after peripheral neurectomies for different branches of trigeminal nerve. SETTING AND DESIGN: The sample was divided into 2 groups by selecting randomly the patients, satisfying inclusion criteria. Both groups were operated under local anesthesia by regional nerve blocks. In one group of patients after peripheral neurectomy, the proximal nerve stump was left alone in the foramina, and in another group of patients, obturation of foramina was done with stainless steel screws after peripheral neurectomy. MATERIALS AND METHODS: Peripheral neurectomy was done on the terminal branches of trigeminal nerve in 14 patients. We selected only those cases that were experiencing pain after Carbamazepine therapy, all our patients were from rural and remote areas where facilities to neurosurgical centers are limited. Elderly patients who were unfit for surgical procedures and those patients who were reluctant for major neurosurgical treatments were considered for the study. RESULTS: Post-surgical pain relief varied from 15 months to 24 months in cases where neurectomy was done without placing stainless steel screws in the foramina. Those cases where peripheral neurectomy was done along with the placement of stainless steel screws in the foramina, none of the patient had painful symptoms even after minimum 2 years of follow-up. Student's `t`-test of 2 groups showed the remission period to be statistically highly significant in patients with stainless steel screw obturation, having P-value <0.0005.Obturating the foramen with stainless steel screws can prevent nerve regeneration. Thus, remission of pain can be prolonged. CONCLUSION: Peripheral neurectomy is thus a safe and effective procedure for elderly patients, for those patients living in remote and rural places that cannot avail major neurosurgical facilities, and for those patients who are reluctant for major neurosurgical procedures.

12.
Appl Biochem Biotechnol ; 167(5): 1052-60, 2012 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-22222433

RESUMO

Microbial xylanases have a promising biotechnological potential to be used in industries. In this study, regulation of xylanase production was examined in Bacillus cereus BSA1. Xylanase production was induced by xylan. The enzyme production further increased in the presence of xylose and arabinose in very low concentration with addition of xylan (0.5% up to 6.02 U/ml). Addition of glucose (about 0.1%) to the media supplemented with xylan repressed xylanase production. Even higher concentration (>0.1%) of xylose and arabinose repressed xylanase biosynthesis. Glucose-mediated repression was partially relived by addition of cyclic adenosine monophosphate. Chemical like 2-4-dinitrophenol, which can inhibit adenosine triphosphate synthesis in cell, repressed xylanase synthesis and it suggested xylanase synthesis to be an energy dependent process.


Assuntos
Bacillus cereus/metabolismo , Endo-1,4-beta-Xilanases/biossíntese , 2,4-Dinitrofenol/farmacologia , Bacillus cereus/efeitos dos fármacos , Carbono/metabolismo , AMP Cíclico/farmacologia , Nucleotídeos/química , Nucleotídeos/farmacologia , Fatores de Tempo , Xilanos/metabolismo
13.
J Ind Microbiol Biotechnol ; 35(4): 245-9, 2008 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-18180968

RESUMO

In the present study, the optimum conditions for the production of xylanase by immobilized spores of Trichoderma reesei SAF3 in calcium alginate beads were determined. The operational stability of the beads during xylanase production under semi-continuous fermentation was also studied. The influence of alginate concentration (1, 2, 3, and 4%) and initial cell loading (100, 200, 300, 400, and 500 beads per flask) on xylanase production was considered. The production of xylanase was found to increase significantly with increasing concentration of alginate and reached a maximum yield of 3.12+/-0.18 U ml(-1) at 2% (w/v). The immobilized cells produced xylanase consistently up to 10 cycles and reached a maximum level at the forth cycle (3.36+/-0.2 U ml(-1)).


Assuntos
Alginatos/química , Endo-1,4-beta-Xilanases/química , Endo-1,4-beta-Xilanases/metabolismo , Microbiologia Industrial , Trichoderma/enzimologia , Reatores Biológicos , Células Imobilizadas/enzimologia , Fermentação , Proteínas Fúngicas/metabolismo , Ácido Glucurônico/química , Ácidos Hexurônicos/química , Índia , Microesferas , Esporos Fúngicos/enzimologia , Especificidade por Substrato , Trichoderma/isolamento & purificação
14.
Artigo em Inglês | VETINDEX | ID: vti-444017

RESUMO

A xylanase producing fungi has been isolated from soil and identified as Trichoderma reesei SAF3. Maximum growth of the organism was found at 48 h under submerged condition in xylan containing enriched medium, whereas highest enzyme production (4.75U/mL) was recorded at 72 h. No detectable cellulase activity was noted during whole cultivation period. The partially purified enzyme hydrolyzed xylan into xylopentose and xylose. All these properties of xylanase highlighten its promising uses in industrial scale.


A partir de solo, isolou-se uma cepa de fungos produtos de xilanase, posteriormente identificado como Trichoderma reesei SAF3. O crescimento máximo do fungo foi obtido após 48h em condições submersas em meio de cultura contendo xilano, enquanto produção máxima de enzima (4,75U/mL) ocorreu em 72h. Durante o período de cultivo, não foi detectada atividade celulásica. A enzima parcialmente purificada hidrolizou xilano a xilopentose e xilose. Essas propriedades da xilanase destacam seu uso promissor em escala industrial.

15.
Braz. j. microbiol ; Braz. j. microbiol;37(4): 462-464, Oct.-Dec. 2006. graf, ilus
Artigo em Inglês | LILACS | ID: lil-442195

RESUMO

A xylanase producing fungi has been isolated from soil and identified as Trichoderma reesei SAF3. Maximum growth of the organism was found at 48 h under submerged condition in xylan containing enriched medium, whereas highest enzyme production (4.75U/mL) was recorded at 72 h. No detectable cellulase activity was noted during whole cultivation period. The partially purified enzyme hydrolyzed xylan into xylopentose and xylose. All these properties of xylanase highlighten its promising uses in industrial scale.


A partir de solo, isolou-se uma cepa de fungos produtos de xilanase, posteriormente identificado como Trichoderma reesei SAF3. O crescimento máximo do fungo foi obtido após 48h em condições submersas em meio de cultura contendo xilano, enquanto produção máxima de enzima (4,75U/mL) ocorreu em 72h. Durante o período de cultivo, não foi detectada atividade celulásica. A enzima parcialmente purificada hidrolizou xilano a xilopentose e xilose. Essas propriedades da xilanase destacam seu uso promissor em escala industrial.


Assuntos
Fungos , Técnicas In Vitro , Trichoderma , Xilanos , Meios de Cultura , Fermentação
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