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1.
Summary Mutant strains were derived from Clostridium thermoaceticum ATCC 39 289 by treatment with chemical mutagenic agents and selective enrichment procedures. Some mutant strains exhibited growth when cultured in media containing 20 mabetm (1.75 g l–1) pyruvate of high-magnesium lime (dolime) above pH 6.0. One strain (G-20) grew and produced acetate when 80 mabetm (7 gl–1) pyruvate or 50 mabetm (2.3 g l–1) formate at pH 5.6 was the sole energy source. In a fed-batch process controlled at pH 6.2, this mutant produced 52.5 g l–1 acetate (equivalent to 72.5 g l–1 Na acetate) and 67 g l–1 calcium-magnesium acetate (CMA) in 140 h when dolime was the neutralizing agent, with 93% substrate utilization. This mutant strain holds promise for CMA production due to its better tolerance of dolime and its ability to synthesize high levels of acetic acid.
Offprint requests to: S. R. Parekh 相似文献
2.
Shafiq Fahad Iqbal Muhammad Raza Syed Hammad Akram Nudrat Aisha Ashraf Muhammad 《Journal of Plant Growth Regulation》2023,42(3):1267-1290
Journal of Plant Growth Regulation - Fullerenols are carbon nanoparticles that have been declared as free radical sponges. There is a need to take a prudent path toward its applications in various... 相似文献
3.
Expression of desmin, laminin and fibronectin during in situ differentiation (decidualization) of rat uterine stromal cells 总被引:2,自引:0,他引:2
Stanley R. Glasser Saara Lampelo M. Idrees Munir JoAnne Julian 《Differentiation; research in biological diversity》1987,35(2):132-142
Immunocytochemical analysis of frozen rat uterine sections containing decidual tissue, formed in response to normal or artificial stimulation of uteri sensitized by endogenous or exogenous hormonal regimens, demonstrated an elevated expression of the intermediate filament protein desmin in decidual cells. Changes in the expression of extracellular matrix (ECM) components were coordinated with the elevated expression of desmin as stromal cells underwent decidualization. In parallel with the pattern of regional decidualization, as determined by elevated desmin expression, laminin accumulated in ECM of decidual cells while an apparent decrease in fibronectin was associated with altered organization at the decidual cell surface. The in situ observations confirm previous results, which indicated that the expression of desmin in decidual cells formed in vivo or in vitro is a valid marker of their differentiation, and resolve questions unanswered in the previous study: (a) desmin (and laminin) appear to be constitutively expressed in non-decidualized stroma at barely detectable levels, (b) desmin is a valid marker of stromal cell differentiation because it is expressed similarly in decidual cells, irrespective of varying experimental protocols for uterine sensitization and stimulation, and (c) desmin expression follows the same regional progression described for the process of decidualization in morphological and histochemical studies. 相似文献
4.
Mohamed S. Elshikh Mohammad Ajmal Ali Fahad Al-Hemaid Soo Yong Kim Meena Elangbam Arun Bahadur Gurung Prasanjit Mukherjee Mohamed El-Zaidy Joongku Lee 《Saudi Journal of Biological Sciences》2022,29(3):1313-1321
The enhanced understanding of chloroplast genomics would facilitate various biotechnology applications; however, the chloroplast (cp) genome / plastome characteristics of plants like Fagonia indica Burm.f. (family Zygophyllaceae), which have the capability to grow in extremely hot sand desert, have been rarely understood. The de novo genome sequence of F. indica using the Illumina high-throughput sequencing technology determined 128,379 bp long cp genome, encode 115 unique coding genes. The present study added the evidence of the loss of a copy of the IR in the cp genome of the taxa capable to grow in the hot sand desert. The maximum likelihood analysis revealed two distinct sub-clades i.e. Krameriaceae and Zygophyllaceae of the order Zygophyllales, nested within fabids. 相似文献
5.
Fahad A. Alhumaydhi 《Saudi Journal of Biological Sciences》2022,29(5):3276-3286
There is a rapid rise in cases of Type-2-diabetes mellitus (T2DM) globally, irrespective of the geography, ethnicity or any other variable factors. The molecular mechanisms that could cause the condition of T2DM need to be more thoroughly analysed to understand the clinical manifestations and to derive better therapeutic regimes. Tools in bioinformatics are used to trace out key gene elements and to identify the key causative gene elements and their possible therapeutic agents. Microarray datasets were retrieved from the Gene expression omnibus database and studied using R to derive different expressed gene (DEG) elements. With the comparison of the expressed genes with disease specific genes in DisGeNET, the final annotated genes were taken for analysis. Gene Ontology studies, Protein–protein interaction (PPI), Co-expression analysis, Gene-drug interactions were performed to scale down the hub genes and to identify the novelty across the genes analysed so far. In vivo and invitro analysis of key genes and the trace of interaction pathway is crucial to better understand the unique outcomes from the novel genes, forming the basis to understand the pathway that ends up causing T2DM. Afterwards, docking was executed enabling recognition of interacting residues involved in inhibition. The complex CCL5-265 and CD8A-40585 thus docked showed best results as is evident from its PCA analysis and MMGBSA calculation. There is now scope for deriving candidate drugs that could possibly detect personalized therapies for T2DM. 相似文献
6.
7.
Muhammad Tariq-Khan Tariq Mukhtar Anjum Munir Johannes Hallmann Holger Heuer 《Journal of Phytopathology》2020,168(6):322-336
The present study documents the root-knot nematodes (RKN) fauna of the Poonch division in Azad Jammu and Kashmir infecting vegetables. An overall prevalence of 40% of RKN was recorded. Of the four districts investigated, maximum prevalence was recorded in district Poonch with 59%, followed by Sudhnuti with 58%. The lowest prevalence of RKN was found in districts Bagh (29%) and Haveli (33%). Out of 15 vegetables investigated, RKN was found on five crops. The highest prevalence of 37.8% was recorded on okra, followed by 31.3% on cucumber and 17.5% on tomato. RKN was less prevalent on eggplant (8.3%) and beans (7.7%). Three RKN species, that is Meloidogyne incognita, Meloidogyne javanica and Meloidogyne arenaria, were found infecting the hosts. M. javanica was found to be the most prevalent followed by M. incognita and M. arenaria. This trend was found in all the districts. Overall prevalence of M. javanica as sole population was 9% and that of M. incognita was 2%. Meloidogyne arenaria was not found in any of the fields as sole population. The prevalence of M. incognita with M. javanica or M. arenaria as mixed populations was 8% and 5%, respectively, and that of M. javanica with M. arenaria was 4%. Similarly, all the three species prevailed as mixed populations in 12% of the fields in the division. The severity of RKN infections, measured as galling index, was found to be variable within each infected field (GI 2–9). Identification of RKN species was based on the morphology of perineal patterns and confirmed by molecular SCAR and CO1 makers based identification. In conclusion, RKN were distributed in the Poonch division and M. javanica was predominant. Cucumber, okra, tomato and eggplant were severely attacked by these nematodes warranting the adoption of stringent control strategies for their management. 相似文献
8.
Muhammad Afzal Imran Kazmi Anwarulabedin Mohsin Quazi Aftab Ahmad Fahad A. Al-Abaasi Faisal Imam Khalid Saad Alharbi Sami I. Alzarea Ameeduzzafar Zafar 《Saudi Journal of Biological Sciences》2021,28(6):3418-3423
The 6-shogaol, is a flavanone type flavonoid that is abundant in citrus fruit and has a wide range of pharmacological effects. The present study attempted to evaluate the antiurolithic effect of 6-shogaol on ethylene glycol (EG) and ammonium chloride (AC)-induced experimental urolithiasis in rats. The efficacy of 6-shogaol 50 mg/kg and 100 mg/kg was studied in EG 0.75% (V/V) and AC 1% (W/V) experimentally induced urolithiasis in rats for 21 days. The weight difference, urine volume, the levels of calcium, phosphate, magnesium, oxalate and uric acid in urine was observed. The blood urea nitrogen, creatinine, uric acid in serum and levels of malondialdehyde (MDA) and glutathione (GSH) were also measured. Histopathological analyses in kidneys were also performed. The rats weights were higher in the 6-shogaol groups than the urolithiasis group. EG caused a significant increase in serum creatinine (p < 0.05), BUN (P < 0.001), and uric acid (p < 0.01) while treatment with Cystone (750 mg/kg), and 6-shogaol (50 and 100 mg/kg) showed the significant reduction in increased serum levels of creatinine (p < 0.001), uric acid (p < 0.01) and BUN (p < 0.001). Administration of EG and AC showed statistically significant (p < 0.001) elevated levels of MDA and reduction in GSH levels. Treatment of Cystone (750 mg/kg), and 6-shogaol (50 and 100 mg/kg) significantly (p < 0.001) reduced MDA levels and an increase GSH levels as compared to EG and AC-treated group. The histological findings further attested antiurolithiatic properties of 6-shogaol. The present study attributed clinical shreds of evidence first time that claiming the significant antiurolithic effect of 6-shogaol and could be a cost-effective candidate for the prevention and treatment of urolithiasis. 相似文献
9.
Khalid Ghilan Asim Mehmood Zafar Ahmed Ahmed Nahari Mohammed J. Almalki Abdulrahman M. Jabour Fahad khan 《Saudi Journal of Biological Sciences》2021,28(1):643-650
BackgroundEfficiency remains one of the most important drivers of decision making in health care system. Fund allocators need to receive structured information about the cost healthcare services from hospitals for better decisions related to resource allocation and budgeting. The objective of the study was to estimate the unit cost for health services offered to inpatients in King Fahd Central hospital (KFCH) Jazan during the financial year 2018.MethodsWe applied a retrospective approach using a top-down costing method to estimate the cost of health care services. Clinical and Administrative departments divided into cost centres, and the unit cost was calculated by dividing the total cost of final care cost centres into the total number of patients discharged in one year. The average cost of inpatient services was calculated based on the average cost of each ward and the number of patients treated.ResultsThe average cost per patient stayed in KFCH was SAR 19,034, with the highest cost of SAR 108,561 for patients in the Orthopedic ward. The average cost of the patient in the Surgery ward, Plastic surgery, Neurosurgery, Medical ward, Pediatric ward and Gynecology ward was SAR 33,033, SAR 29,425, SAR 23,444, SAR 20,450, SAR 9579 and SAR 8636 respectively.ConclusionThis study provides necessary information about the cost of health care services in a tertiary care setting. This information can be used as a primary tool and reference for further studies in other regions of the country. Hence, this data can help to provide a better understanding of tertiary hospital costing in the region to achieve the privatization objective. 相似文献
10.
Mohammed K. Al-Sadoon Mohammed Fahad Albeshr Bilal Ahamad Paray Abdul Rahman Al-Mfarij 《Saudi Journal of Biological Sciences》2021,28(1):582-586
Snakebite being medical emergency and known cause for increased mortality needs assessment and treatment on high-priority bases, even in patients of snakebite who appear fine initially. The current retrospective study presents the snake bites in Saudi Arabia from 2015 to 2018 reported by General Administration of Statistics and Information, Ministry of Health, Kingdom of Saudi Arabia. The data presented in the current study, was extracted, analyzed, and reported after getting ethical approval from institutional committee. Totally, 14,679 cases of snakebites were reported during the four-year study period, with a higher prevalence in males (80%) in their productive age. Most patients were within the age group between 25 and 44 followed by 44 to 64 years. The majority of snakebite affected inhabitants were reported from farms of the rural areas, commonly during night hours of spring and summer seasons when snakes are very active. Only 36 (0.24%) patients out of 14,679 were reported dead and 14,643 (99.63%) were discharged after the treatment. Awareness among the general public should be encouraged and early diagnosis and usage of proper snake antivenoms could be life-saving. The delay in appropriate treatment can lead to significant morbidity and mortality. 相似文献