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1.
World J Gastroenterol ; 30(26): 3221-3228, 2024 Jul 14.
Article in English | MEDLINE | ID: mdl-39086638

ABSTRACT

BACKGROUND: Glucagon-like peptide-1 receptor agonists (GLP-1 RA) are effective in diabetes and obesity, reducing hyperglycemia by increasing insulin release and delaying gastric emptying. However, they can cause gastroparesis, raising concerns about aspiration during procedures. Recent guidelines advise discontinuing GLP-1 RA before surgery to reduce the risk of pulmonary aspiration. AIM: To evaluate the effect of GLP-1 RAs on gastric residual contents during endoscopic procedures. METHODS: A retrospective chart review at BronxCare Health System, New York, from January 2019 to October 2023, assessed gastric residue and aspiration in GLP-1 RA patients undergoing endoscopic procedures. Two groups were compared based on dietary status before the procedure. Data included demographics, symptoms of gastroparesis, opiate use, hemoglobin A1c, GLP-1 agonist indication, endoscopic details, and aspiration occurrence. IBM SPSS was used for analysis, calculating means, standard deviations, and applying Pearson's chi-square and t-tests for associations, with P < 0.05 as being significant. RESULTS: During the study, 306 patients were included, with 41.2% on a clear liquid/low residue diet and 58.8% on a regular diet before endoscopy. Most patients (63.1%) were male, with a mean age of 60 ± 12 years. The majority (85.6%) were on GLP-1 RAs for diabetes, and 10.1% reported digestive symptoms before endoscopy. Among those on a clear liquid diet, 1.5% had residual food at endoscopy compared to 10% on a regular diet, which was statistically significant (P = 0.03). Out of 31 patients with digestive symptoms, 13% had residual food, all from the regular diet group (P = 0.130). No complications were reported during or after the procedures. CONCLUSION: The study reflects a significant rise in GLP-1 RA use for diabetes and obesity. A 24-hour liquid diet seems safe for endoscopic procedures without aspiration. Patients with upper gastrointestinal symptoms might have a higher residual food risk, though not statistically significant. Further research is needed to assess risks based on diabetes duration, gastroparesis, and GLP-1 RA dosing, aiming to minimize interruptions in therapy during procedures.


Subject(s)
Gastroparesis , Glucagon-Like Peptide-1 Receptor , Humans , Retrospective Studies , Male , Female , Middle Aged , Glucagon-Like Peptide-1 Receptor/agonists , Aged , Gastroparesis/prevention & control , Gastroparesis/etiology , Gastroparesis/epidemiology , Gastroparesis/drug therapy , Gastric Emptying/drug effects , Hypoglycemic Agents/therapeutic use , Hypoglycemic Agents/administration & dosage , Endoscopy, Gastrointestinal/methods , Diabetes Mellitus, Type 2/drug therapy , Adult , Glucagon-Like Peptide-1 Receptor Agonists
2.
Article in English | MEDLINE | ID: mdl-39077862

ABSTRACT

Though there has been advancement in the management of lung cancer, it is not well utilized due to its limited availability and high cost. This is a prospective observational study done at a tertiary care center from January 2014 to December 2022, involving patients with primary lung cancer. After tumor-node-metastasis staging and molecular testing, the patients received chemotherapy, radiotherapy, surgery, targeted therapy, and immunotherapy in various combinations as per the prevailing National Comprehensive Cancer Network Guidelines. 92 patients were enrolled in the study, with the mean age being 58.94±10.33 and 72 (78.26%) being males. 69 (75%) patients were either current or former smokers. 78 (84.78%) patients had an Eastern Cooperative Oncology Group (ECOG) score of 0-2 while the remaining had an ECOG of 3-4. 80 (86.95%) patients had non-small cell lung cancer (NSCLC) [44 (47.83%) adenocarcinoma, 25 (27.17%) squamous cell carcinoma, and 11 (11.95%) NSCLC: not otherwise specified], while 12 (13.04%) patients had small cell lung cancer. One (1.08%) patient each presented in stage I and stage II, 31 (33.69%) patients presented in stage III, and 59 (64.13%) patients presented in stage IV. 44 patients with adenocarcinoma were subjected to mutational analysis, and an epidermal growth factor receptor mutation was found in 13 (29.5%) patients. None of the patients had ALK mutation, ROS-1 rearrangement, or BRAF mutation. PD-L1 expression was evaluated in 9 patients with NSCLC, and it was found in 6 (66.66%) patients. The overall mean survival was 12.7 months. The mean survival for patients with stages I, II, III, and IV was 70, 96, 8.1, and 12.7 months, respectively. Survival in stage IV was better than in stage III, as the eligible patients received targeted therapy and immunotherapy. Targeted therapy and immunotherapy have improved survival. Molecular analysis should be done whenever indicated, and eligible patients must be administered targeted therapy and immunotherapy.

4.
Clin Dysmorphol ; 33(2): 63-68, 2024 Apr 01.
Article in English | MEDLINE | ID: mdl-38441200

ABSTRACT

Aniridia is an autosomal dominant condition characterized by the complete or partial absence of the iris, often with additional presentations such as foveal hypoplasia, nystagmus, cataract, glaucoma and other ocular abnormalities. Most cases are caused by heterozygous mutations in the paired box 6 gene (PAX6), which codes for a transcription factor that regulates eye development. Four patients from our hospital who presented with ocular phenotypes were recruited for research sequencing with informed consent. Sanger sequencing of PAX6 coding exons or exome sequencing was performed on genomic DNA from venous blood samples. Variants in PAX6 were identified in the four patients. Two variants are recurrent single-nucleotide substitutions - one is a substitution found in a patient with bilateral aniridia, whereas the other is a splice variant in a patient with nystagmus and neuroblastoma. The other two variants are novel and found in two patients with isolated aniridia. Both are small duplications that are predicted to lead to premature termination. For the recurrent variants, the comparison of phenotypes for patients with identical variants would shed light on the mechanisms of pathogenesis, and the discovery of two novel variants expands the spectrum of PAX6 mutations.


Subject(s)
Aniridia , Cataract , Humans , Face , Aniridia/genetics , Cataract/genetics , Exons , Asia, Southeastern , PAX6 Transcription Factor/genetics
5.
Am J Clin Pathol ; 162(1): 12-16, 2024 Jul 05.
Article in English | MEDLINE | ID: mdl-38437878

ABSTRACT

OBJECTIVES: Gender equity studies have shown that women are underrepresented in journal editor in chief positions, which confer major professional opportunities and influence. We sought to systematically investigate editor in chief gender and journal attributes within pathology. METHODS: We constructed a journal data set using the Scimago Journal & Country Rank and Clarivate Journal Citation Reports databases. We also included official journals of the major medical societies for the 12 pathology subspecialties recognized by the Association of American Medical Colleges. The final data set included 126 journals. We obtained editor in chief gender, impact factor, publication model (ie, hybrid access vs open access), year of founding, and geographic location for all included pathology journals. RESULTS: Women made up only 18% of the 141 total editor in chief positions. This inequity was present irrespective of all pathology journal variables studied. Among 10 journals with 2 editor in chief positions, 5 had only men and 5 had 1 man and 1 woman. All 3 journals with 3 editor in chief positions had 2 men and 1 woman. CONCLUSIONS: Women are significantly underrepresented among editor in chiefs across pathology journals. Journals and affiliated members should advocate for diversity among these influential positions, given their impact on research, science, and medicine.


Subject(s)
Pathology , Periodicals as Topic , Humans , Female , Periodicals as Topic/statistics & numerical data , Male , Journal Impact Factor , Gender Equity
8.
Pak J Med Sci ; 39(4): 1124-1128, 2023.
Article in English | MEDLINE | ID: mdl-37492301

ABSTRACT

Objective: To identify genetic causes of Shabbir syndrome in two patients of Pakistani origin. Methods: In the present study, we have investigated a Pakistani family with two affected members segregating Laryngo-onycho-cutaneous (LOC) syndrome. The patients were diagnosed as suspected cases of LOC based on phenotypes including abnormal larynx, nails, and hyperpigmentation in patients' eyes. Genetic investigation was done by performing whole exome sequencing (WES) using DNA of the patients. Sanger sequencing was performed to validate WES findings and segregation analysis in the family. Results: Data analysis of exomes and Sanger sequencing of patients revealed a homozygous one base pair duplication (NM_000227.6; LAMA3; c.151dup; p.Val51GlyfsTer4) in LAMA3 in the patients. Parents of the patients were heterozygous for the identified variant. Conclusion: Previously, the same variant has been found in most of the Pakistani Punjabi patients affected with LOC. Therefore, Pakistani Punjabi families affected with Shabbir Syndrome may be screened for c.151dup variant in LAMA3 using targeted sequencing. Sanger sequencing is a cost-effective and time-saving technique as compared to whole exome/genome sequencing. Hence, developing ethnicity-specific LAMA3 targeted molecular diagnostic test would be cost-effective. Further, the study would assist in carrier testing and prenatal diagnosis of the affected families.

9.
Medicine (Baltimore) ; 102(26): e34185, 2023 Jun 30.
Article in English | MEDLINE | ID: mdl-37390240

ABSTRACT

BACKGROUND: The Amplatzer Amulet (AA) and Watchman devices (WD) are the 2 most frequently used devices for percutaneous LAA closure globally. OBJECTIVE: To evaluate the safety and clinical outcomes associated with these 2 devices in patients undergoing percutaneous LAA closure. METHOD: We systematically searched all electronic databases from inception until February 21, 2023. The primary endpoint was procedure related complications. Secondary endpoints were device related thrombus, stroke, cardiovascular mortality, peri device leak, systemic embolism, and all-cause mortality. RESULTS: A total of 3 randomized clinical trials with 2150 patients were included in this meta-analysis. The mean age was 75 and 76 years in the Amplatzer group and in the Watchman group, respectively. The odds of procedure-related complications (OR, 1.80 [95% CI: 1.21-2.67], P < .001) were significantly higher among patients with AA compared to the WD. However, the odds of all-cause mortality (OR, 0.75 (95% CI: 0.49-1.16), P = .20), stroke (OR, 0.79 [95% CI: 0.47-1.34], P = .39), systemic/pulmonary embolism (OR, 1.34 [95% CI: 0.30-6.04], P = .70), and major bleeding (OR, 1.10 [95% CI: 0.83-1.48], P = .50) were comparable between the two devices. The odds of device related thrombus (OR, 0.72 [95% CI: 0.46-1.14], P = .17) was comparable between both the group of patients, however the incidence of peri device leak was significantly lower in AA group (OR, 0.41 [95% CI: 0.26-0.66], P < .001) compared with WD group of patients. CONCLUSION: The AA was not superior to the Watchman device in terms of safety and efficacy. However, the Amulet occluder was associated with a higher incidence of procedure-related complications, and lower peri device leak.


Subject(s)
Atrial Appendage , Cardiac Surgical Procedures , Pulmonary Embolism , Stroke , Humans , Aged , Atrial Appendage/surgery , Databases, Factual , Stroke/epidemiology , Stroke/etiology , Randomized Controlled Trials as Topic
10.
Indian J Otolaryngol Head Neck Surg ; 75(Suppl 1): 83-87, 2023 Apr.
Article in English | MEDLINE | ID: mdl-37206739

ABSTRACT

The most popular objective physiologic test for detecting hearing loss that is in use today is the ABR, however it is not frequency specific. The frequency specific tool available for evaluation of hearing is ASSR. The study is aimed to assess the ability of ASSR to estimate hearing thresholds and identify the ideal modulation frequency in hearing impaired personnel. All subjects and controls were subjected to PTA to determine presence/absence of hearing loss, and the nature and configuration of the hearing loss if any. The subjects were then subjected to ASSR testing to objectively ascertain hearing thresholds. The PTA thresholds obtained and the hearing thresholds obtained by ASSR were correlated in this study. The study was carried out in 100 subjects under the age of 50 years (50 with normal hearing & 50 with impaired hearing by PTA) after obtaining informed consent. Moderate correlation was found between PTA and ASSR thresholds only in certain frequencies while in other frequencies the correlation though present, was low. This study concluded that ASSR system could be used to estimate hearing thresholds only approximately as no significant linear correlations were found between PTA thresholds and ASSR at the tested frequencies.

11.
Genes (Basel) ; 14(5)2023 05 19.
Article in English | MEDLINE | ID: mdl-37239474

ABSTRACT

Bardet-Biedl syndrome (BBS) is a rare clinically and genetically heterogeneous autosomal recessive multi-systemic disorder with 22 known genes. The primary clinical and diagnostic features include six different hallmarks, such as rod-cone dystrophy, learning difficulties, renal abnormalities, male hypogonadism, post-axial polydactyly, and obesity. Here, we report nine consanguineous families and a non-consanguineous family with several affected individuals presenting typical clinical features of BBS. In the present study, 10 BBS Pakistani families were subjected to whole exome sequencing (WES), which revealed novel/recurrent gene variants, including a homozygous nonsense mutation (c.94C>T; p.Gln32Ter) in the IFT27 (NM_006860.5) gene in family A, a homozygous nonsense mutation (c.160A>T; p.Lys54Ter) in the BBIP1 (NM_001195306.1) gene in family B, a homozygous nonsense variant (c.720C>A; p.Cys240Ter) in the WDPCP (NM_015910.7) in family C, a homozygous nonsense variant (c.505A>T; p.Lys169Ter) in the LZTFL1 (NM_020347.4) in family D, pathogenic homozygous 1 bp deletion (c.775delA; p.Thr259Leufs*21) in the MKKS/BBS5 (NM_170784.3) gene in family E, a pathogenic homozygous missense variant (c.1339G>A; p.Ala447Thr) in BBS1 (NM_024649.4) in families F and G, a pathogenic homozygous donor splice site variant (c.951+1G>A; p?) in BBS1 (NM_024649.4) in family H, a pathogenic bi-allelic nonsense variant in MKKS (NM_170784.3) (c.119C>G; p.Ser40*) in family I, and homozygous pathogenic frameshift variants (c.196delA; p.Arg66Glufs*12) in BBS5 (NM_152384.3) in family J. Our findings extend the mutation and phenotypic spectrum of four different types of ciliopathies causing BBS and also support the importance of these genes in the development of multi-systemic human genetic disorders.


Subject(s)
Bardet-Biedl Syndrome , Ciliopathies , Polydactyly , Humans , Male , Bardet-Biedl Syndrome/diagnosis , Codon, Nonsense , Mutation , Polydactyly/genetics , Microtubule-Associated Proteins/genetics , Cytoskeletal Proteins/genetics , Phosphate-Binding Proteins/genetics
12.
J Gene Med ; 25(10): e3513, 2023 10.
Article in English | MEDLINE | ID: mdl-37178061

ABSTRACT

BACKGROUND: Population diversity is important and rare disease isolates can frequently reveal novel homozygous or biallelic mutations that lead to expanded clinical heterogeneity, with diverse clinical presentations. METHODS: The present study describes two consanguineous families with a total of seven affected individuals suffering from a clinically similar severe syndromic neurological disorder, with abnormal development and central nervous system (CNS) and peripheral nervous system (PNS) abnormalities. Whole exome sequencing (WES) and Sanger sequencing followed by 3D protein modeling was performed to identify the disease-causing gene. RNA was extracted from the fresh blood of both families affected and healthy individuals. RESULTS: The families were clinically assessed in the field in different regions of Khyber Pakhtunkhwa. Magnetic resonance imagining was obtained in the probands and blood was collected for DNA extraction and WES was performed. Sanger sequencing confirmed a homozygous, likely pathogenic mutation (GRCh38: chr17:42684199G>C; (NM_003632.3): c.333G>C);(NP_003623.1): p.(Trp111Cys) in the CNTNAP1 gene in family A, previously associated with Congenital Hypo myelinating Neuropathy 3 (CHN3; OMIM # 618186) and a novel nonsense variant in family B, (GRCh38: chr16: 57654086C>T; NC_000016.10 (NM_001370440.1): c.721C>T); (NP_001357369.1): p.(Gln241Ter) in the ADGRG1 gene previously associated with bilateral frontoparietal polymicrogyria (OMIM # 606854); both families have extended CNS and PNS clinical manifestations. In addition, 3D protein modeling was performed for the missense variant, p.(Trp111Cys), identified in the CNTNAP1, suggesting extensive secondary structure changes that might lead to improper function or downstream signaling. No RNA expression was observed in both families affected and healthy individuals hence showing that these genes are not expressed in blood. CONCLUSIONS: In the present study, two novel biallelic variants in the CNTNAP1 and ADGRG1 genes in two different consanguineous families with a clinical overlap in the phenotype were identified. Thus, the clinical and mutation spectrum is expanded to provide further evidence that CNTNAP1 and ADGRG1 are very important for widespread neurological development.


Subject(s)
Cell Adhesion Molecules, Neuronal , Mutation, Missense , Humans , Consanguinity , Mutation , Genes, Recessive , Phenotype , Cell Adhesion Molecules, Neuronal/genetics
14.
Curr Probl Cardiol ; 48(5): 101595, 2023 May.
Article in English | MEDLINE | ID: mdl-36690312

ABSTRACT

The Racial disparity between the clinical outcomes post interventions among Peripheral Artery Disease (PAD) have not been well studied, with limited literature available. We conducted a meta-analysis to evaluate the post-procedure outcomes among PAD patients between Black and White race. We systematically searched all electronic databases from inception until first November 2022. The primary endpoint was major amputation within 30 days. Secondary endpoints were myocardial infarction (MI) within 30 days, mortality within 30 days, and all-cause mortality (ACM). A total of 136,395 patients were included in the analysis, with 117,177 patients of the White race and 19,218 patients of the Black race. The mean age of the patients in each group was (66.41 vs 62.75). Most common comorbidity among White and Black patients was diabetes mellitus (42.15% vs 55.90%), and hypertension (HTN) (39.53% vs 90.07%). The odds of major amputation within 30 days was significantly higher in Black patients compared to white patients (OR, 0.40 (95% CI: 0.19-0.84, P = 0.02), while the odds of MI was higher in White patients compared to Black race PAD patients (OR, 1.29, (95%CI:1.05-1.58), P < 0.02). There was no significant difference in ACM (OR, 0.97(95%CI: 0.64-1.47, P = 0.88), and mortality within 30 days (OR, 1.09(95%CI:0.77-1.53, P = 0.64) between both groups. To our knowledge, this is the first meta-analysis with the largest sample size thus far, highlighting that Black patients are at a higher risk for major amputation within 30 days compared to white patients although mortality remains comparable between the 2 races.


Subject(s)
Myocardial Infarction , Peripheral Arterial Disease , Humans , Black or African American , Myocardial Infarction/epidemiology , Peripheral Arterial Disease/epidemiology , Peripheral Arterial Disease/surgery , Risk Factors , Treatment Outcome , White People , Middle Aged , Aged
15.
Environ Technol ; 44(15): 2300-2314, 2023 Jun.
Article in English | MEDLINE | ID: mdl-34994296

ABSTRACT

Low density Polyethylene (LDPE) in various forms has become a part of life. Its accretion due to non degradable nature is concern, endangering life on earth. Amongst various methods of LDPE disposal bioremediation is regarded as ecofriendly & widely accepted. Current investigation was an attempt to isolate potent PE degrading fungus from municipal landfill soils of Bhopal, India loaded with plastic waste.16 fungal isolates were recorded from the site; PE deteriorating fungus was screened using mineral salt agar medium amended with 3% LDPE powder as sole carbon source. The isolate Penicillium citrinum showed fast fungal colony growth in screening medium was selected for biodegradation study. P.citrinum showed 38.82 ± 1.08% weight loss of untreated LDPE pieces; to improve the degradation capacity nitric acid pretreatment was performed; biodegradation was significantly stimulated by 47.22 ± 2.04% after it's pretreatment. Laccase, lipase, esterase & manganese peroxidase activities were assayed by spectrophotometer. LDPE biodegradation was analyzed by weight loss %, change in pH during fungal growth, field emission scanning electron microscopy (FE-SEM), fourier transform infrared spectroscopy (FTIR) & thermogravimetric analysis (TGA). FTIR spectra showed appearance of new functional groups assigned to hydrocarbon biodegradation, confirming enzymatic role in process. Changes in FTIR spectra of LDPE samples (untreated & pretreated) before & after biodegradation & surface changes in the biodegraded LDPE (indicated from FE-SEM) confirmed depolymerization of LDPE. Further changes in thermal decomposition rates of biodegraded samples in comparison to control, validate biodegradation. This is the first report signifying high competence of P.citrinum in LDPE degradation without prior pretreatment.


Subject(s)
Penicillium , Polyethylene , Polyethylene/chemistry , Plastics , Biodegradation, Environmental , Waste Disposal Facilities , Penicillium/metabolism , India
16.
Mitochondrion ; 73: 62-71, 2023 Nov.
Article in English | MEDLINE | ID: mdl-38506094

ABSTRACT

Rheumatoid arthritis (RA) is a chronic, autoimmune, and inflammatory disease that primarily targets the joints, leading to cartilage and bone destruction.Fibroblast-like synoviocytes (FLS) are specialized cells of the synovial lining in the joint that plays a fundamental role in the development of RA. Particularly, FLS of RA patients (RA-FLS) in the joint exhibit specific characteristics like higher invading and immunogenic properties, hyperproliferation, and reduced apoptotic capacity, suggesting a dysfunctional mitochondrial pool in these cells. Mitochondria are emerging as a potential organelle that can decide cellular immunometabolism, invasion properties, and cell death. Accordingly, multiplestudies established that mitochondria are crucial in establishing RA. However, the underlying mechanism of impaired mitochondrial function in RA remains poorly understood. This review will provide an overview of the mitochondrial role in the progression of RA, specifically in the context of FLS biology. We will also outline how mitochondria-centric therapeutics can be achieved that would yield novel avenues of research in pathological mediation and prevention.


Subject(s)
Arthritis, Rheumatoid , Mitochondrial Diseases , Synoviocytes , Humans , Synoviocytes/metabolism , Synoviocytes/pathology , Arthritis, Rheumatoid/metabolism , Cells, Cultured , Fibroblasts/metabolism , Mitochondrial Diseases/pathology , Cell Proliferation
17.
Ann Med Surg (Lond) ; 84: 104884, 2022 Dec.
Article in English | MEDLINE | ID: mdl-36582908

ABSTRACT

Introduction: Myocarditis is the inflammation of the myocardium. The clinical presentation of myocarditis ranges from asymptomatic state to acute heart failure which may mimic acute coronary events. Because of the similar presentation of chest pain, elevated cardiac enzymes, and electrocardiographic (ECG) changes, acute myocarditis may rarely masquerade as acute myocardial infarction (AMI). High suspicion is often necessary for treating such patients, keeping in mind the different treatment protocols required for managing each pathology. Methods: SCARE 2020 Guidelines. Case report: We report a case of a young female presenting with sudden onset chest pain with ECG changes suggestive of acute anterior wall myocardial infarction (AWMI). Further investigations ruled out AWMI, and she was diagnosed with acute myocarditis. She was treated for myocarditis and showed a prompt recovery. Discussion: Acute myocarditis may present clinically similarly to ACS; hence a high level of suspicion is required to differentiate the two entities. The absence of significant cardiovascular risk factors for atherosclerotic coronary artery disease, absence of RWMA, and normal coronary angiogram are further suggestive of myocarditis.

18.
Biotechnol Rep (Amst) ; 36: e00761, 2022 Dec.
Article in English | MEDLINE | ID: mdl-36159743

ABSTRACT

The therapeutic efficacy of Artemisia annua L. is governed by artemisinin (ART), prevalently produced by A. annua extraction. Due to the modest amount of ART (0.01-1 %dw) in this plant, commercialization of ACTs is difficult. In this study, the floral-dip based transformation protocol for A. annua was developed to enhance expression of artemisinin biosynthesis genes and ART content. For dipping, the effective infiltration media components were optimized, and to obtain high transformation (26.9%) partially open bud stage capitulum of floral development was used. Hygromycin phospho-transferase (hptII) selection marker was used to validate the transformed T1 progenies. The copy numbers of the transgene (hptII) in T1 progenies were determined using a sensitive, high-throughput SYBR Green based quantitative RT-PCR. The results of the hptII transgene were compared with those of the low copy number, internal standard (hmgr). Using optimised PCR conditions, one, two and three transgene copies in T1 transformants were achieved.

19.
ACS Omega ; 7(35): 30967-30977, 2022 Sep 06.
Article in English | MEDLINE | ID: mdl-36092636

ABSTRACT

With the advent of modern lifestyles, diabetes-related comorbidities attributed the importance of low-caloric natural sweetener plants such as Stevia rebaudiana. This plant is the viable source of steviol glycosides (SGs) and other economically important secondary metabolites. Glandular trichomes (GTs) play the role as a reservoir for all secondary products present in the plant species. Therefore, the present study was carried out to evaluate the influence of different plant growth regulators (PGRs) on GT density and its impact on the SG content. The direct shoot regeneration system was developed on Murashige and Skoog (MS) + benzyl aminopurine (BAP) (1.0 mg/L) + naphthaleneacetic acid (NAA) (0.5 mg/L), and MS + BAP (1.5 mg/L) + NAA (0.5 mg/L) from nodal and leaf explants, respectively. Among the combination of PGRs used, MS medium fortified with BAP (1.0 mg/L) and 2,4-dichlorophenoxyacetic acid (2,4-D) (0.5 mg/L) played a significant role in increasing the GT density on leaf and stem tissues of S. rebaudiana. Furthermore, high-performance thin-layer chromatography and gas chromatography-mass spectrophotometry data confirmed a notable rise in SGs and other valuable secondary metabolites. Thus, the protocol developed can be used for the propagation of stevia with an improved metabolic profile at a large scale.

20.
J Fungi (Basel) ; 8(4)2022 Mar 22.
Article in English | MEDLINE | ID: mdl-35448558

ABSTRACT

Fungal volatile organic compounds (VOCs) represent promising candidates for biopesticide fumigants to control crop pests and pathogens. Herein, VOCs produced using three strains of the entomopathogenic fungus Metarhizium brunneum were identified via GC-MS and screened for antimicrobial activity. The VOC profiles varied with fungal strain, development state (mycelium, spores) and culture conditions. Selected VOCs were screened against a range of rhizosphere and non-rhizosphere microbes, including three Gram-negative bacteria (Escherichia coli, Pantoea agglomerans, Pseudomonas aeruginosa), five Gram-positive bacteria (Micrococcus luteus, Staphylococcus aureus, Bacillus subtilis, B. megaterium, B. thuringiensis), two yeasts (Candida albicans, Candida glabrata) and three plant pathogenic fungi (Pythium ultimum, Botrytis cinerea, Fusarium graminearum). Microbes differed in their sensitivity to the test compounds, with 1-octen-3-ol and isovaleric acid showing broad-spectrum antimicrobial activity. Yeasts and bacteria were inhibited by the same VOCs. Cryo-SEM showed that both yeasts and bacteria underwent some form of "autolysis", where all components of the cell, including the cell wall, disintegrated with little evidence of their presence in the clear, inhibition zone. The oomycete (P. ultimum) and ascomycete fungi (F. graminearum, B. cinerea) were sensitive to a wider range of VOCs than the bacteria, suggesting that eukaryotic microbes are the main competitors to M. brunneum in the rhizosphere. The ability to alter the VOC profile in response to nutritional cues may assist M. brunneum to survive among the roots of a wide range of plant species. Our VOC studies provided new insights as to how M. brunneum may protect plants from pathogenic microbes and correspondingly promote healthy growth.

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