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1.
J Surg Oncol ; 129(5): 869-875, 2024 Apr.
Article in English | MEDLINE | ID: mdl-38185838

ABSTRACT

BACKGROUND AND OBJECTIVES: The accepted approach to pain management following open pancreatoduodenectomy (PD) remains controversial, with the most recent enhanced recovery after surgery (ERAS) protocols recommending epidural anesthesia (EA). Few studies have investigated intrathecal (IT) morphine, combined with transversus abdominis plane (TAP) blocks. We aim to compare the different approaches to pain management for open PD. METHODS: Patients who underwent open PD at our institution from 2020 to 2022 were included in the study. Patient characteristics, pain management, and postoperative outcomes between EA, IT morphine with TAP blocks, and TAP blocks only were compared using univariate analysis. RESULTS: Fifty patients were included in the study (58% male, median age 66 years [interquartile range, IQR: 58-73]). Most patients received IT morphine (N = 24, 48%) or EA (N = 18, 36%). The TAP block-only group required higher doses of postoperative narcotics while hospitalized (p = 0.004) and at discharge (p = 0.017). The IT morphine patients had a shorter median time to Foley removal (p = 0.007). Postoperative pain scores, non-opioid administration, postoperative bolus requirements, postoperative outcomes, and length of stay were similar between pain modalities. CONCLUSIONS: IT morphine and EA showed comparable efficacy with superior results compared to TAP blocks alone. Integration of IT morphine into PD ERAS protocols should be considered.


Subject(s)
Anesthesia, Epidural , Morphine , Humans , Male , Aged , Female , Analgesics, Opioid , Pancreaticoduodenectomy/adverse effects , Abdominal Muscles/surgery , Pain, Postoperative/drug therapy , Pain, Postoperative/etiology , Pain, Postoperative/prevention & control
2.
Cureus ; 15(11): e49718, 2023 Nov.
Article in English | MEDLINE | ID: mdl-38033448

ABSTRACT

Background The prevalence of diabetes mellitus (DM) in Saudi Arabia is among the highest in the Middle East and North Africa (MENA) regions. Various complications of DM can cause problems in the long term. One of the most prevalent microvascular problems and the primary cause of blindness is diabetic retinopathy (DR), and a significant proportion of the population with diabetes eventually develop diabetes retinopathy. Recognizing and understanding DR may be crucial for patients in identifying and averting this complication.  Objectives The objective of this atudy is to assess the awareness of DR among patients with type 2 DM at primary healthcare centers in Madinah, Saudi Arabia.  Methods This cross-sectional study involved a survey of patients with diabetes who attended Madinah primary care clinics between August and September 2023. The study was conducted in Madinah, Saudi Arabia, from May to November 2023.  Results A total of 240 patients participated with a median age of 49.7 years and a gender distribution of 121 (50.4%) men. Overall, less than half of patients had a fair level of knowledge (47.1%) and a good level of knowledge (42.1%) about DR, whereas 10.8% had poor knowledge. Physicians were the primary source of information for patients, followed by the internet, family, and friends. Higher levels of education, diabetes that had been present for a longer period, and regular eye exams were associated with better understanding. This study emphasizes the importance of improving patient knowledge and awareness of DR.  Conclusions We observed a high level of awareness of DR among participants. Furthermore, higher awareness was associated with longer disease duration and compliance with diabetes treatment.

3.
J Prev Alzheimers Dis ; 9(4): 731-742, 2022.
Article in English | MEDLINE | ID: mdl-36281678

ABSTRACT

BACKGROUND: The Comparative Effectiveness Dementia and Alzheimer's Registry (CEDAR) trial demonstrated that individualized, multi-domain interventions improved cognition and reduced the risk of Alzheimer's disease (AD). As biological sex is a significant risk factor for AD, it is essential to explore the differential effectiveness of targeted clinical interventions in women vs. men. METHODS: Patients were recruited from an Alzheimer's Prevention Clinic. Subjects with normal cognition, subjective cognitive decline, or asymptomatic preclinical AD were classified as "Prevention". Subjects with mild cognitive impairment due to AD or mild AD were classified as "Early Treatment." The primary outcome was the change from baseline to 18-months on the modified-Alzheimer's Prevention Cognitive Composite. Secondary outcomes included a cognitive aging composite, AD and cardiovascular (CV) risk scales, and serum biomarkers. Subjects who adhered to > 60% of recommendations in the CEDAR trial were included in this a priori sub-group analysis to examine whether individualized intervention effects were modified by sex (n=80). RESULTS: In the Prevention group, both women (p=0.0205) and men (p=0.0044) demonstrated improvements in cognition with no sex differences (p=0.5244). In the Early Treatment group, there were also no significant sex differences in cognition (p=0.3299). In the Prevention group, women demonstrated greater improvements in the Multi-Ethnic Study of Atherosclerosis risk score (MESA-RS) than men (difference=1.5, p=0.0013). Women in the Early Treatment group demonstrated greater improvements in CV Risk Factors, Aging and Incidence of Dementia (CAIDE) risk score (difference=2.3, p=0.0067), and the MESA-RS (difference=4.1, p<0.001). CONCLUSIONS: Individualized multi-domain interventions are equally effective at improving cognition in women and men. However, personally-tailored interventions led to greater improvements in calculated AD and CV risk, and CV blood biomarkers, in women compared to men. Future study in larger cohorts is necessary to further define sex differences in AD risk reduction in clinical practice.


Subject(s)
Alzheimer Disease , Cognitive Dysfunction , Female , Humans , Male , Alzheimer Disease/drug therapy , Biomarkers , Cognition , Cognitive Dysfunction/psychology , Risk Factors , Clinical Trials as Topic
4.
J Taibah Univ Med Sci ; 17(3): 506-515, 2022 Jun.
Article in English | MEDLINE | ID: mdl-35079243

ABSTRACT

Objective: Teledentistry conveniently delivers dental care when in-person visits are restricted, such as during the COVID-19 pandemic. This study aimed to assess Saudi Arabian patients' accuracy, perceptions, knowledge, attitudes, and challenges regarding teledentistry used for diagnosis during the COVID-19 pandemic, as well as its accuracy, versus traditional dental visits. Methods: A single-blind, parallel-group randomised controlled trial design was used. The 70 participants were randomised equally into study and control groups. While the control group waited, the study group received teledentistry diagnoses which were compared with baseline clinical examinations retrieved from the UQU dental hospital, Makkah, KSA. After the intervention was completed, all participants answered a questionnaire. Results: There were no significant differences between the groups in knowledge or attitudes regarding teledentistry. However, study group participants had more favourable experiences with teledentistry. They reported good accuracy with diagnosis and recording of their chief complaints (74.3%), number of missing teeth (74.3%), number of filled teeth (71.4%), and oral hygiene status (65.7%). Additionally, moderate accuracy was reported on recording of health complaints (51.4%) and number of decayed teeth (40.?%). The number of decayed teeth and the decayed, missing, and filled teeth (DMF) index scores reported using teledentistry were significantly (p < 0.05) higher than reported in the baseline examinations. Conclusion: Teledentistry is widely accepted by patients and can be efficient for preliminary examinations, particularly during pandemic lockdowns or in more frequently occurring situations such as severe weather conditions, but subsequent clinical examination is necessary for maximally accurate diagnoses.

5.
Indian J Otolaryngol Head Neck Surg ; 74(Suppl 3): 4336-4340, 2022 Dec.
Article in English | MEDLINE | ID: mdl-36742602

ABSTRACT

Temporal bone fracture accounts for 30-70% of skull fractures. Temporal bone trauma is associated with severe traumatic brain injury. Temporal bone fractures are invariably due to road traffic accidents (RTA). Temporal bone fractures are traditionally classified as transverse, longitudinal or mixed fractures depending on their relationship to the petrous pyramid. Recent studies classify temporal bone fractures as otic capsule sparing (OCS) and otic capsule violating (OCV) types and has more relevance with the prognosis of hearing loss and complications. To study of type and degree of hearing loss following temporal bone fractures according to the old and new classification of temporal bone fractures. The prospective study of 35 cases of head injuries attending emergency department was conducted in the Department of Otorhinolaryngology, SNMC and H.S.K. Hospital & Research centre, Bagalkot during the study period from January 2019 to June 2020. High Resolution Computed Tomography (HRCT) of bilateral temporal bone was done to look for type of temporal bone fractures. Pure tone audiometry (PTA) to assess degree and type of hearing loss. Appropriate statistical analysis at the end of study was done. Most patients were in age group of 21-40 years. Among 35 cases, 30 were longitudinal fractures, 4 were transverse and 1 was mixed.27 cases were OCS and 8 of OCV type.OCV type of fractures are having higher degree of hearing loss. Longitudinal type of temporal bone fractures constitutes majority. Hearing loss was more in OCV type.

6.
Hum Mol Genet ; 30(17): 1632-1648, 2021 08 12.
Article in English | MEDLINE | ID: mdl-34077515

ABSTRACT

Fragile X-associated tremor and ataxia syndrome (FXTAS) is a late-onset, progressive neurodegenerative disorder characterized by tremors, ataxia and neuropsychological problems. This disease is quite common in the general population with approximately 20 million carriers worldwide. The risk of developing FXTAS increases dramatically with age, with about 45% of male carriers over the age of 50 being affected. FXTAS is caused by a CGG-repeat expansion (CGGexp) in the fragile X mental retardation 1 (FMR1) gene. CGGexp RNA is translated into the FMRpolyG protein by a mechanism called RAN translation. Although both gene and pathogenic trigger are known, no therapeutic interventions are available at this moment. Here, we present, for the first time, primary hippocampal neurons derived from the ubiquitous inducible mouse model which is used as a screening tool for targeted interventions. A promising candidate is the repeat binding, RAN translation blocking, small molecule 1a. Small molecule 1a shields the disease-causing CGGexp from being translated into the toxic FMRpolyG protein. Primary hippocampal neurons formed FMRpolyG-positive inclusions, and upon treatment with 1a, the numbers of FMRpolyG-positive inclusions are reduced. We also describe for the first time the formation of FMRpolyG-positive inclusions in the liver of this mouse model. Treatment with 1a reduced the insoluble FMRpolyG protein fraction in the liver but not the number of inclusions. Moreover, 1a treatment had a reducing effect on the number of Rad23b-positive inclusions and insoluble Rad23b protein levels. These data suggest that targeted small molecule therapy is effective in an FXTAS mouse model and has the potential to treat CGGexp-mediated diseases, including FXTAS.


Subject(s)
Ataxia/genetics , Fragile X Mental Retardation Protein/genetics , Fragile X Syndrome/genetics , Tremor/genetics , Animals , Ataxia/physiopathology , Cell Communication , DNA Repair Enzymes/genetics , DNA-Binding Proteins/genetics , Disease Models, Animal , Fragile X Mental Retardation Protein/metabolism , Fragile X Syndrome/physiopathology , Humans , Male , Mice , Neurons/metabolism , Tremor/physiopathology , Trinucleotide Repeat Expansion
7.
Brain Commun ; 3(1): fcab007, 2021.
Article in English | MEDLINE | ID: mdl-33709078

ABSTRACT

CGG repeat expansions within the premutation range (55-200) of the FMR1 gene can lead to Fragile X-associated tremor/ataxia syndrome and Fragile X-associated neuropsychiatric disorders. These CGG repeats are translated into a toxic polyglycine-containing protein, FMRpolyG. Pathology of Fragile X-associated tremor/ataxia syndrome and Fragile X-associated neuropsychiatric disorders comprises FMRpolyG- and p62-positive intranuclear inclusions. Diagnosing a FMR1-premutation carrier remains challenging, as the clinical features overlap with other neurodegenerative diseases. Here, we describe two male cases with Fragile X-associated neuropsychiatric disorders-related symptoms and mild movement disturbances and novel pathological features that can attribute to the variable phenotype. Macroscopically, both donors did not show characteristic white matter lesions on MRI; however, vascular infarcts in cortical- and sub-cortical regions were identified. Immunohistochemistry analyses revealed a high number of FMRpolyG intranuclear inclusions throughout the brain, which were also positive for p62. Importantly, we identified a novel pathological vascular phenotype with inclusions present in pericytes and endothelial cells. Although these results need to be confirmed in more cases, we propose that these vascular lesions in the brain could contribute to the complex symptomology of FMR1-premutation carriers. Overall, our report suggests that Fragile X-associated tremor/ataxia syndrome and Fragile X-associated neuropsychiatric disorders may present diverse clinical involvements resembling other types of dementia, and in the absence of genetic testing, FMRpolyG can be used post-mortem to identify premutation carriers.

8.
Appl Microbiol Biotechnol ; 105(1): 105-117, 2021 Jan.
Article in English | MEDLINE | ID: mdl-33215258

ABSTRACT

The world economy depends heavily on crude oil. With a conventional oil recovery process, only one-third of crude oil is extracted. Various technologies have been developed to maximize the recovery of oil resources from natural reservoirs. Polymer technology has been used in many oil fields around the world. The biopolymer pullulan, produced by some Aureobasidium species, has been used in many industrial applications, but no research has been conducted regarding its use in the microbial enhancement of oil recovery (MEOR). Here, we investigate the potential of pullulan produced by newly isolated species Aureobasidium mangrovei SARA-138H for enhancement of oil recovery. Our results indicate that under optimized conditions, that is, sucrose as the carbon source in the medium, a pH of 9, incubation at 25 °C, and 250 rpm agitation, the fungus was able to produce 10 g/L of pullulan. The maximum viscosity achieved under these conditions was 318 cP after 15 days of incubation. Pullulan solution (10 g/L) showed the ability to recover 36.7% of heavy crude oil after 34.2% of secondary oil recovery. However, diluted pullulan in brine at the ratio (1:1) resulted in the recovery of 20.23% of oil from the residual oil in the core after 22.6% of secondary oil recovery. A 20-day injectivity test revealed that pullulan passed smoothly through the core, causing no blockage. It was concluded that pullulan from A. mangrovei SARA-138H was able to increase oil recovery to a degree comparable to that achieved with many polymers used in oil fields around the world. KEY POINTS: • First report of biopolymer "pullulan" from A. mangrovie. • Optimum conditions for pullulan production were obtained. • Pullulan recovered 36.7% of heavy oil from residual oil in place, with good injectivity.


Subject(s)
Aureobasidium , Petroleum , Biopolymers , Culture Media , Viscosity
9.
Front Mol Biosci ; 7: 599101, 2020.
Article in English | MEDLINE | ID: mdl-33381520

ABSTRACT

Fragile X-associated tremor/ataxia syndrome (FXTAS) is a rare neurodegenerative disorder caused by a 55-200 CGG repeat expansion in the 5' untranslated region of the Fragile X Mental Retardation 1 (FMR1) gene. FXTAS is characterized by progressive cerebellar ataxia, Parkinsonism, intention tremors and cognitive decline. The main neuropathological hallmark of FXTAS is the presence of ubiquitin-positive intranuclear inclusions in neurons and astrocytes throughout the brain. The molecular pathology of FXTAS involves the presence of 2 to 8-fold elevated levels of FMR1 mRNA, and of a repeat-associated non-AUG (RAN) translated polyglycine peptide (FMRpolyG). Increased levels of FMR1 mRNA containing an expanded CGG repeat can result in cellular toxicity by an RNA gain-of-function mechanism. The increased levels of CGG repeat-expanded FMR1 transcripts may create RNA foci that sequester important cellular proteins, including RNA-binding proteins and FMRpolyG, in intranuclear inclusions. To date, it is unclear whether the FMRpolyG-positive intranuclear inclusions are a cause or a consequence of FXTAS disease pathology. In this report we studied the relation between the presence of neuronal intranuclear inclusions and behavioral deficits using an inducible mouse model for FXTAS. Neuronal intranuclear inclusions were observed 4 weeks after dox-induction. After 12 weeks, high numbers of FMRpolyG-positive intranuclear inclusions could be detected in the hippocampus and striatum, but no clear signs of behavioral deficits related to these specific brain regions were found. In conclusion, the observations in our inducible mouse model for FXTAS suggest a lack of correlation between the presence of intranuclear FMRpolyG-positive aggregates in brain regions and specific behavioral phenotypes.

11.
J Prev Alzheimers Dis ; 7(2): 104-111, 2020.
Article in English | MEDLINE | ID: mdl-32236399

ABSTRACT

BACKGROUND: Alzheimer's disease (AD) is the most common and most costly chronic neurodegenerative disease globally. AD develops over an extended period prior to cognitive symptoms, leaving a "window of opportunity" for targeted risk-reduction interventions. Further, this pre-dementia phase includes early physiological changes in sleep and autonomic regulation, for which wearable biosensor devices may offer a convenient and cost-effective method to assess AD-risk. METHODS: Patients with a family history of AD and no or minimal cognitive complaints were recruited from the Alzheimer's Prevention Clinic at Weill Cornell Medicine and New York-Presbyterian. Of the 40 consecutive patients screened, 34 (85%) agreed to wear a wearable biosensor device (WHOOP). One subject (2.5%) lost the device prior to data collection. Of the remaining subjects, 24 were classified as normal cognition and were asymptomatic, 6 were classified as subjective cognitive decline, and 3 were amyloid-positive (one with pre-clinical AD, one with pre-clinical Lewy-Body Dementia, and one with mild cognitive impairment due to AD). Sleep-cycle, autonomic (heart rate variability [HRV]) and activity measures were collected via WHOOP. Blood biomarkers and neuropsychological testing sensitive to cognitive changes in pre-clinical AD were obtained. Participants completed surveys assessing their sleep-patterns, exercise habits, and attitudes towards WHOOP. The goal of this prospective observational study was to determine the feasibility of using a wrist-worn biosensor device in patients at-risk for AD dementia. Unsupervised machine learning was performed to first separate participants into distinct phenotypic groups using the multivariate biometric data. Additional statistical analyses were conducted to examine correlations between individual biometric measures and cognitive performance. RESULTS: 27 (81.8%) participants completed the follow-up surveys. Twenty-four participants (88.9%) were satisfied with WHOOP after six months, and twenty-three (85.2%) wanted to continue wearing WHOOP. K-means clustering separated participants into two groups. Group 1 was older, had lower HRV, and spent more time in slow-wave sleep (SWS) than Group 2. Group 1 performed better on two cognitive tests assessing executive function: Flanker Inhibitory Attention/Control (FIAC) (p=.031), and Dimensional Change Card Sort (DCCS) (p=.061). In Group 1, DCCS was correlated with SWS (ρ=.68, p=0.024) and HRV (ρ=.6, p=0.019). In Group 2, DCCS was correlated with HRV (ρ=.55, p=0.018). There were no significant differences in blood biomarkers between the two groups. CONCLUSIONS: Wearable biosensor devices may be a feasible tool to assess AD-related physiological changes. Longitudinal collection of sleep and HRV data may potentially be a non-invasive method for monitoring cognitive changes related to pre-clinical AD. Further study is warranted in larger populations.


Subject(s)
Actigraphy/instrumentation , Alzheimer Disease/prevention & control , Wearable Electronic Devices , Adult , Aged , Feasibility Studies , Female , Heart Rate , Humans , Male , Middle Aged , Risk Assessment , Sleep , Surveys and Questionnaires
12.
Front Mol Biosci ; 7: 31, 2020.
Article in English | MEDLINE | ID: mdl-32219099

ABSTRACT

Fragile X-associated tremor/ataxia syndrome (FXTAS) is a late-onset neurodegenerative monogenetic disorder affecting carriers of premutation (PM) forms of the FMR1 gene, resulting in a progressive development of tremors, ataxia, and neuropsychological problems. This highly disabling disease is quite common in the general population with an estimation of about 20 million PM carriers worldwide. The chances of developing FXTAS increase dramatically with age, with about 45% of male carriers over the age of 50 being affected. Both the gene and pathogenic trigger, a mutant expansion of CGG RNA, causing FXTAS are known. This makes it an interesting disease to develop targeted therapeutic interventions for. Yet, no such interventions are available at this moment. Here we discuss in silico, in vitro, and in vivo approaches and how they have been used to identify the molecular determinants of FXTAS pathology. These approaches have yielded substantial information about FXTAS pathology and, consequently, many markers have emerged to play a key role in understanding the disease mechanism. Integration of the different approaches is expected to provide crucial information about the value of these markers as either therapeutic target or biomarker, essential to monitor therapeutic interventions in the future.

13.
Acta Neuropathol Commun ; 7(1): 27, 2019 02 26.
Article in English | MEDLINE | ID: mdl-30808398

ABSTRACT

The fragile X premutation is a CGG trinucleotide repeat expansion between 55 and 200 repeats in the 5'-untranslated region of the fragile X mental retardation 1 (FMR1) gene. Human carriers of the premutation allele are at risk of developing the late-onset neurodegenerative disorder, fragile X-associated tremor/ataxia syndrome (FXTAS). Characteristic neuropathology associated with FXTAS includes intranuclear inclusions in neurons and astroglia. Previous studies recapitulated these histopathological features in neurons in a knock-in mouse model, but without significant astroglial pathology. To determine the role of astroglia in FXTAS, we generated a transgenic mouse line (Gfa2-CGG99-eGFP) that selectively expresses a 99-CGG repeat expansion linked to an enhanced green fluorescent protein (eGFP) reporter in astroglia throughout the brain, including cerebellar Bergmann glia. Behaviorally these mice displayed impaired motor performance on the ladder-rung test, but paradoxically better performance on the rotarod. Immunocytochemical analysis revealed that CGG99-eGFP co-localized with GFAP and S-100ß, but not with NeuN, Iba1, or MBP, indicating that CGG99-eGFP expression is specific to astroglia. Ubiquitin-positive intranuclear inclusions were found in eGFP-expressing glia throughout the brain. In addition, intracytoplasmic ubiquitin-positive inclusions were found outside the nucleus in distal astrocyte processes. Intriguingly, intranuclear inclusions, in the absence of eGFP mRNA and eGFP fluorescence, were present in neurons of the hypothalamus and neocortex. Furthermore, intranuclear inclusions in both neurons and astrocytes displayed immunofluorescent labeling for the polyglycine peptide FMRpolyG, implicating FMRpolyG in the pathology found in Gfa2-CGG99 mice. Considered together, these results show that Gfa2-CGG99 expression in mice is sufficient to induce key features of FXTAS pathology, including formation of intranuclear inclusions, translation of FMRpolyG, and deficits in motor function.


Subject(s)
Astrocytes/physiology , Ataxia/genetics , Cell Communication/physiology , Fragile X Mental Retardation Protein/genetics , Fragile X Syndrome/genetics , Motor Skills Disorders/genetics , Tremor/genetics , Trinucleotide Repeat Expansion/genetics , Animals , Astrocytes/metabolism , Astrocytes/pathology , Ataxia/metabolism , Ataxia/pathology , Base Sequence , Fragile X Mental Retardation Protein/biosynthesis , Fragile X Syndrome/metabolism , Fragile X Syndrome/pathology , Gene Expression , Male , Mice , Mice, Inbred C57BL , Mice, Transgenic , Motor Skills Disorders/metabolism , Motor Skills Disorders/pathology , Tremor/metabolism , Tremor/pathology
14.
Cureus ; 10(7): e3001, 2018 Jul 19.
Article in English | MEDLINE | ID: mdl-30250763

ABSTRACT

Introduction Diabetic foot ulcers are a pressing complication of diabetes mellitus. Wound care requires a significant proportion of healthcare resources. It is imperative, therefore, for healthcare professionals to possess sound knowledge of the disease along with a positive attitude to ensure better clinical practice. Our literature search revealed a scarcity of data pertaining to diabetic foot ulcers. Therefore, this study aims to evaluate the knowledge and attitudes of nurses regarding diabetic foot care. Methods A cross-sectional study design was employed, a pre-validated and pre-tested questionnaire was used to collect data from a sample size of 250 nurses working at two tertiary care hospitals in Karachi, Pakistan. The study was conducted over a period of three months (January to March 2018) and included all nurses who possessed at least one year of clinical experience in diabetic ulcer care. The statistical software employed was SPSS version 19 (IBM Corp., Armonk, NY, US). Non-parametric tests and descriptive statistics were used for data analysis and statistical significance was assumed at a p-value of less than 0.5. Results Only 54% of the nurses in our study possessed adequate knowledge of diabetic foot ulcers. The mean score of knowledge was 74.9 (±9.5). Macdonald's standard criteria for learning outcomes was used to gauge the knowledge levels of our study population. Nurses performed best in the domain of ulcer care with 65.3% of the participants possessing good knowledge of the topic. The overall attitude of nurses towards patients with diabetic ulcers was positive.  Conclusion This study highlights important gaps in nurses' knowledge and sheds light on the lack of evidence-based practice. Poor knowledge can compromise healthcare standards, even with the presence of positive attitudes. Hence, a comprehensive revision of nursing curricula across local tertiary hospitals for allowing nurses to update their knowledge is warranted.

15.
Scientifica (Cairo) ; 2018: 9230143, 2018.
Article in English | MEDLINE | ID: mdl-29755805

ABSTRACT

The identification of potential hydrocarbon utilizing bacteria is an essential requirement in microbial enhanced oil recovery (MEOR). Molecular approaches like proteomic and genomic characterization of the isolates are replacing the traditional method of identification with systemic classification. Genotypic profiling of the isolates includes fingerprint or pattern-based technique and sequence-based technique. Understanding community structure and dynamics is essential for studying diversity profiles and is challenging in the case of microbial analysis. The present study aims to understand the bacterial community composition from different heavy oil contaminated soil samples collected from geographically related oil well areas in Oman and to identify spore-forming hydrocarbon utilizing cultivable bacteria. V4 region of 16S rDNA gene was the target for Ion PGM™. A total of 825081 raw sequences were obtained from Ion torrent from all the 10 soil samples. The species richness and evenness were found to be moderate in all the samples with four main phyla, Firmicutes, Bacteroidetes, Proteobacteria, and Actinobacteria, the most abundant being Firmicutes. Bacillus sp. ubiquitously dominated in all samples followed by Paenibacillus, which was followed by Brevibacillus, Planococcus, and Flavobacterium. Principal Coordinate Analysis (PCoA) and UPGMA dendrogram clustered the 10 soil samples into four main groups. Weighted UniFrac significance test determined that there was significant difference in the communities present in soil samples examined. It can be concluded that the microbial community was different in all the 10 soil samples with Bacillus and Paenibacillus sp. as predominating genus. The 16S rDNA sequencing of cultivable spore-forming bacteria identified the hydrocarbon utilizing bacteria as Bacillus and Paenibacillus sp. and the nucleotide sequences were submitted to NCBI GenBank under accession numbers KP119097-KP119115. Bacillus and Paenibacillus sp., which were relatively abundant in the oil fields, can be recommended to be chosen as candidates for hydrocarbon utilization study.

16.
PLoS One ; 12(2): e0171432, 2017.
Article in English | MEDLINE | ID: mdl-28196087

ABSTRACT

Microbial Enhanced Oil Recovery (MEOR) is a potential technology for residual heavy oil recovery. Many heavy oil fields in Oman and elsewhere have difficulty in crude oil recovery because it is expensive due to its high viscosity. Indigenous microbes are capable of improving the fluidity of heavy oil, by changing its high viscosity and producing lighter oil fractions. Many spore-forming bacteria were isolated from soil samples collected from oil fields in Oman. Among the isolates, an autochthonous spore-forming bacterium was found to enhance heavy oil recovery, which was identified by 16S rDNA sequencing as Paenibacillus ehimensis BS1. The isolate showed maximum growth at high heavy oil concentrations within four days of incubation. Biotransformation of heavy crude oil to light aliphatic and aromatic compounds and its potential in EOR was analyzed under aerobic and anaerobic reservoir conditions. The isolates were grown aerobically in Bushnell-Haas medium with 1% (w/v) heavy crude oil. The crude oil analyzed by GC-MS showed a significant biotransformation from the ninth day of incubation under aerobic conditions. The total biotransformation of heavy crude oil was 67.1% with 45.9% in aliphatic and 85.3% in aromatic fractions. Core flooding experiments were carried out by injecting the isolates in brine supplemented with Bushnell-Haas medium into Berea sandstone cores and were incubated for twelve days under oil reservoir conditions (50°C). The extra recovered oil was analyzed by GC-MS. The residual oil recovered from core flood experiments ranged between 10-13% compared to the control experiment. The GC-MS analyses of the extra recovered oil showed 38.99% biotransformation of heavy to light oil. The results also indicated the presence of 22.9% extra aliphatic compounds in the residual crude oil recovered compared to that of a control. The most abundant compound in the extra recovered crude oil was identified as 1-bromoeicosane. The investigations showed the potential of P. ehimensis BS1 in MEOR technology by the biotransformation of heavy to lighter crude oil under aerobic and reservoir conditions. Heavy oil recovery and biotransformation to lighter components are of great economic value and a few studies have been done.


Subject(s)
Paenibacillus/metabolism , Petroleum/metabolism , Biodegradation, Environmental , DNA, Bacterial/genetics , Paenibacillus/genetics , Petroleum/microbiology , RNA, Ribosomal, 16S/genetics
17.
Am J Primatol ; 79(1): 1-8, 2017 Jan.
Article in English | MEDLINE | ID: mdl-26496532

ABSTRACT

Hair loss is commonly used as an indicator of well being in primate facilities, yet it has been shown to also occur in otherwise healthy pregnant and postpartum females. There is significant variability in the incidence of hair loss during these important developmental periods, reasons for which remain unclear. We studied female rhesus monkeys (Macaca mulatta, n = 47) with and without hair loss in pregnancy/postpartum. We hypothesized that, similar to previously published reports, pregnancy would result in an increased likelihood of hair loss, and that hair loss would be correlated with higher hair cortisol concentrations (HCCs). We further hypothesized that hair loss among pregnant females is related to differential maternal investment. We studied a subset of monkeys (n = 26) from mid-to-late pregnancy through peak lactation, some of which exhibited hair loss in the perinatal period (n = 15), and some of which did not (n = 11). We examined fetal measurements, infant birth weight, infant growth rate, and milk yield volume (MYV) in the first 30 days as indices of investment. We found that pregnant monkeys showed a greater incidence of hair loss across the study year (χ2(2) = 6.55, P = 0.038), and that mothers with hair loss had significantly higher HCCs in pregnancy than those without (F(2,28) = 3.8, P = 0.017, ηp2 = 0.21). HCCs in pregnancy were correlated with severity of hair loss in the neonatal period (r(37) = 0.42, P = 0.008). Moreover, HCCs in pregnancy were positively correlated with infant birth weight (r(12) = 0.56, P = 0.038), infant growth rate (r(12) = 0.64, P = 0.014), and MYV (r(11) = 0.85, P < 0.001) for alopecic but not non-alopecic mothers. These mothers did not differ in fetal measurements, infant birth weight/growth rate, or MYV. Our results suggest that hair loss in some monkeys, especially during the birthing season, may be a signal of greater physiological stress during pregnancy and differential investment by mothers to their offspring. Am. J. Primatol. 79:e22489, 2017. © 2015 Wiley Periodicals, Inc.


Subject(s)
Alopecia/veterinary , Lactation , Macaca mulatta , Pregnancy, Animal/physiology , Animals , Female , Hair , Mothers , Pregnancy
18.
Am J Primatol ; 79(1): 1-8, 2017 Jan.
Article in English | MEDLINE | ID: mdl-27008590

ABSTRACT

Hair loss is common in macaque colonies. Very little is known about the relationship between psychological stress and hair loss. We initially examined alopecia and hair cortisol concentrations in 198 (89 male) rhesus macaques from three primate centers and demonstrated replicability of our previous finding that extensive alopecia (>30% hair loss) is associated with increased chronic cortisol concentrations and significantly affected by facility. A subset of these monkeys (142 of which 67 were males) were sampled twice approximately 8 months apart allowing us to examine the hypotheses that gaining hair should be associated with decreases in cortisol concentrations and vice versa. Hair loss was digitally scored using ImageJ software for the first sample. Then visual assessment was used to examine the second sample, resulting in three categories of coat condition: (i) monkeys that remained fully haired; (ii) monkeys that remained alopecic (with more than 30% hair loss); or (iii) monkeys that showed more than a 15% increase in hair. The sample size for the group that lost hair was too small to be analyzed. Consistent with our hypothesis, monkeys that gained hair showed a significant reduction in hair cortisol concentrations but this effect only held for females. Coat condition changed little across sampling periods with only 25 (11 male) monkeys showing a greater than 15% gain of hair. Twenty (7 male) monkeys remained alopecic, whereas 97 (49 males) remained fully haired. Hair cortisol was highly correlated across samples for the monkeys that retained their status (remained alopecic or retained their hair). Am. J. Primatol. 79:e22547, 2017. © 2016 Wiley Periodicals, Inc.


Subject(s)
Alopecia/veterinary , Biomarkers , Macaca mulatta , Stress, Physiological , Animals , Female , Hair , Hydrocortisone , Hypothalamo-Hypophyseal System , Male
19.
Front Microbiol ; 7: 1853, 2016.
Article in English | MEDLINE | ID: mdl-27933041

ABSTRACT

The biosurfactant production by Bacillus licheniformis W16 and evaluation of biosurfactant based enhanced oil recovery (EOR) using core-flood under reservoir conditions were investigated. Previously reported nine different production media were screened for biosurfactant production, and two were further optimized with different carbon sources (glucose, sucrose, starch, cane molasses, or date molasses), as well as the strain was screened for biosurfactant production during the growth in different media. The biosurfactant reduced the surface tension and interfacial tension to 24.33 ± 0.57 mN m-1 and 2.47 ± 0.32 mN m-1 respectively within 72 h, at 40°C, and also altered the wettability of a hydrophobic surface by changing the contact angle from 55.67 ± 1.6 to 19.54°± 0.96°. The critical micelle dilution values of 4X were observed. The biosurfactants were characterized by different analytical techniques and identified as lipopeptide, similar to lichenysin-A. The biosurfactant was stable over wide range of extreme environmental conditions. The core flood experiments showed that the biosurfactant was able to enhance the oil recovery by 24-26% over residual oil saturation (Sor). The results highlight the potential application of lipopeptide biosurfactant in wettability alteration and microbial EOR processes.

20.
Front Microbiol ; 6: 1324, 2015.
Article in English | MEDLINE | ID: mdl-26635782

ABSTRACT

Biosurfactant production using Candida bombicola ATCC 22214, its characterization and potential applications in enhancing oil recovery were studied at laboratory scale. The seed media and the production media were standardized for optimal growth and biosurfactant production. The production media were tested with different carbon sources: glucose (2%w/v) and corn oil (10%v/v) added separately or concurrently. The samples were collected at 24 h interval up to 120 h and checked for growth (OD660), and biosurfactant production [surface tension (ST) and interfacial tension (IFT)]. The medium with both glucose and corn oil gave better biosurfactant production and reduced both ST and IFT to 28.56 + 0.42mN/m and 2.13 + 0.09mN/m, respectively within 72 h. The produced biosurfactant was quite stable at 13-15% salinity, pH range of 2-12, and at temperature up to 100°C. It also produced stable emulsions (%E24) with different hydrocarbons (pentane, hexane, heptane, tridecane, tetradecane, hexadecane, 1-methylnaphthalene, 2,2,4,4,6,8-heptamethylnonane, light and heavy crude oil). The produced biosurfactant was extracted using ethyl acetate and characterized as a mixture of sophorolipids (SPLs). The potential of SPLs in enhancing oil recovery was tested using core-flooding experiments under reservoir conditions, where additional 27.27% of residual oil (Sor) was recovered. This confirmed the potential of SPLs for applications in microbial enhanced oil recovery.

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