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Comparative efficacy of craniotomy versus craniectomy in surgical management of acute subdural hematoma: A systematic review and meta-analysis. J Clin Neurosci 2024; 124:154-168. [PMID: 38718611 DOI: 10.1016/j.jocn.2024.04.010] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/14/2023] [Revised: 04/07/2024] [Accepted: 04/09/2024] [Indexed: 05/18/2024]
Abstract
INTRODUCTION Acute subdural hematoma (ASDH), a predominantly lethal neurosurgical emergency in the settings of traumatic brain injury, requires surgical evacuation of hematoma, via craniotomy or craniectomy. The clinical practices vary, with no consensus over the superiority of either procedure. AIM To evaluate whether craniotomy or craniectomy is the optimal approach for surgical evacuation of ASDH. METHODS After a comprehensive search of PubMed, Google Scholar, Scopus, and Cochrane Central Register of Controlled Trials (CENTRAL) up to January 2024, to identify relevant studies, a meta-analysis was performed using a random-effects model, and risk ratios were calculated with 95% confidence intervals (CIs). For quality assessment, the Cochrane risk of bias tool and Newcastle-Ottawa Scale were applied. RESULTS Out of 2143 potentially relevant studies, 1875 were deemed suitable for screening. Eighteen studies were included in the systematic review. Thirteen studies, in which 1589 patients underwent craniotomy and 1452 patients underwent craniectomy, allowed meta-analysis. Pooled estimates showed that there was no significant correlation of mortality at 6 months (RR 1.14;95 % CI; 0.94-1.38 P = 0.18) and 12 months (RR 1.17; 95 % CI; 0.84-1.63 P = 0.36) with the two surgical modalities. A positive association was observed between improved functional outcomes at 6-months and craniotomy (RR 0.76; 95 % CI; 0.62-0.93 P = 0.008), however, no significant difference was observed between the two treatment groups at 12 months follow-up (RR 0.89; 95 % CI; 0.72-1.09 P = 0.26). Craniotomy reported a significantly higher proportion of patients discharged to home (RR 0.63; 95 % CI; 0.49-0.83 P = 0.0007), whereas incidence of residual subdural hematoma was significantly lower in the craniectomy group (RR 0.70; 95 % CI; 0.52-0.94 P = 0.02). CONCLUSION Craniectomy is associated with poor clinical outcomes. However, with long-term follow-up, no difference in mortality and functional outcomes is observed in either of the patient populations. On account of equivocal evidence regarding the efficacy of craniectomy over craniotomy in the realm of long-term outcomes, utmost preference shall be directed toward craniotomy as it is less invasive and associated with fewer complications.
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Safety and efficacy of clot-dissolving therapies for submassive pulmonary embolism: A network meta-analysis of randomized controlled trials. CARDIOVASCULAR REVASCULARIZATION MEDICINE 2024; 62:73-81. [PMID: 38176962 DOI: 10.1016/j.carrev.2023.12.011] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/02/2023] [Revised: 12/05/2023] [Accepted: 12/18/2023] [Indexed: 01/06/2024]
Abstract
BACKGROUND Acute pulmonary embolism (PE) is a serious condition that needs quick and effective treatment. Anticoagulation therapy is the usual care for most PE patients but may not work well for higher-risk ones. Thrombolysis breaks the clot and improves blood flow. It can be given systemically or locally. Ultrasound-assisted catheter-directed thrombolysis (USAT) is a new technique that boosts clot-busting drugs. This network meta-analysis compares death, bleeding, and benefits of four treatments in acute submassive PE. METHODS We comprehensively searched relevant databases up to July 2023 for RCTs. The outcomes encompassed all-cause mortality, major and minor bleeding, PE recurrence, and hospital stay duration. Bayesian network meta-analysis computed odds ratios (OR) and 95 % CI estimates. RESULTS In this network meta-analysis of 23 RCTs involving 2521 PE patients, we found that SCDT had the most favorable performance for mortality, as it had the lowest odds ratio (OR) among the four interventions (OR 5.41e-42; 95 % CI, 5.68e-97, 1.37e-07). USAT had the worst performance for major bleeding, as it had the highest OR among the four interventions (OR 4.73e+04; 95 % CI, 1.65, 9.16e+13). SCDT also had the best performance for minor bleeding, as it had the lowest OR among the four interventions (OR 5.68e-11; 95 % CI, 4.97e-25, 0.386). CONCLUSION Our meta-analysis suggests that SCDT is the most effective treatment intervention in improving the risks of All-cause mortality and bleeding. Thrombolytic therapy helps in improving endpoints including the risk of PE recurrence and the duration of hospital stay.
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Treating Pulmonary Arterial Hypertension With Sotatercept: A Meta-Analysis. Cureus 2024; 16:e51867. [PMID: 38327917 PMCID: PMC10849008 DOI: 10.7759/cureus.51867] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/20/2023] [Accepted: 01/08/2024] [Indexed: 02/09/2024] Open
Abstract
Pulmonary arterial hypertension (PAH) results from proliferative remodeling and narrowing of the pulmonary vasculature. Sotatercept is a first-in-class fusion protein that has recently garnered attention for showing improvements in patients with PAH. This meta-analysis of randomized controlled trials (RCTs) assesses the overall efficacy of Sotatercept in treating PAH. PubMed, Google Scholar, and Clinicaltrials.gov were searched using relevant keywords and MeSH terms. Studies were included if RCTs compared Sotatercept with placebo in patients with PAH. Our comprehensive literature search yielded 3,127 results, of which two RCTs with 429 patients were included in this meta-analysis. The patients were on background therapy for PAH. Results of the meta-analysis show that when compared with placebo, Sotatercept improved the six-minute walk distance (mean difference [MD] 34.99; 95% confidence interval [CI] 19.02-50.95; P < 0.0001), the World Health Organization (WHO) functional class (odds ratio [OR] 2.50; 95% CI 1.50-4.15; P = 0.0004), and pulmonary vascular resistance (PVR, MD -253.90; 95% CI -356.05 to -151.75; P < 0.00001). However, reduction in N-terminal pro-B-type natriuretic peptide (NT-proBNP, MD -1563.14; 95% CI -3271.93 to 145.65; P = 0.07) was not statistically significant in the Sotatercept group versus placebo. In conclusion, Sotatercept improves the six-minute walk distance, WHO functional class, and PVR in patients with PAH receiving background therapy. However, the effect on NT-proBNP levels was not statistically significant. More research is needed to assess the clinical relevance of these findings.
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Left Bundle Branch Pacing: A Paradigm Shift in Physiological Pacing for Patients With Atrioventricular Block and Preserved Left Ventricular Systolic Function, A Systematic Review and Meta-analysis. Curr Probl Cardiol 2023; 48:101983. [PMID: 37473943 DOI: 10.1016/j.cpcardiol.2023.101983] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/07/2023] [Accepted: 07/16/2023] [Indexed: 07/22/2023]
Abstract
His-Purkinje conduction system pacing (HPCSP) via His bundle pacing (HBP) and Left Bundle Branch Pacing (LBBP) offer a physiological approach to pacing by restoring normal ventricular activation. This meta-analysis compares the feasibility, outcomes, and success rates of HBP and LBBP in patients with atrioventricular block (AVB) and preserved left ventricular function. A systematic search identified studies comparing LBBP with HBP in AVB patients with preserved systolic function. Primary outcomes included QRS duration, success rates, pacing threshold, and improvement in R-wave amplitudes. Secondary outcomes were procedure time and fluoroscopy time. Random-effects models calculated odds ratios (OR) and mean differences (MD) with 95% confidence intervals (CI). Methodological quality was assessed using the Newcastle-Ottawa scale. Among 382 screened articles, seven observational studies involving 1035 patients were analyzed. The mean age was 69.9 years, the mean LVEF was 59.3%, and the average follow-up duration was 8.7 months. LBBP showed higher R-wave amplitudes (MD 7.88, 95% CI 7.26 to 8.50, P < 0.0001) and lower pacing thresholds (MD -0.64, 95% CI -0.81 to -0.47, P < 0.0001) compared to HBP. LBBP had shorter procedure time (MD -17.81, 95% CI -30.44 to -5.18, P = 0.006) and reduced fluoroscopy time (MD -5.39, 95% CI -8.81 to -1.97, P = 0.002). No significant differences were observed in QRS duration or success rates. LBBP offers advantages over HBP, including improved electrical activation, lower pacing thresholds, and shorter procedure and fluoroscopy times. Success rates and QRS duration reductions were comparable between LBBP and HBP. These findings support LBBP as a feasible and effective alternative to HBP in AVB patients with preserved systolic function.
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Clinical Efficacy and Safety of Bempedoic Acid in High Cardiovascular Risk Patients: A Systematic Review and Meta-analysis of Randomized Controlled Trials. Curr Probl Cardiol 2023; 48:102003. [PMID: 37516330 DOI: 10.1016/j.cpcardiol.2023.102003] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/20/2023] [Accepted: 07/24/2023] [Indexed: 07/31/2023]
Abstract
Bempedoic acid (BA) is the new addition to lipid-lowering medications. This systematic review and meta-analysis of randomized controlled trials (RCTs) assess the clinical efficacy and safety of BA in high cardiovascular (CV) risk patients along with its effects on low-density lipoprotein cholesterol (LDL-C) and total cholesterol. PubMed, Google Scholar, Cochrane Central Register of Controlled Trials, Embase, and ClinicalTrials.gov were searched for RCTs comparing BA with placebo, reporting CV outcomes. Seven RCTs with a total of 17,816 patients were selected for the analysis. Results showed that BA significantly reduced the risk of MACE (RR 0.87, 95% CI 0.80-0.94; P = 0.007), nonfatal myocardial infarction (RR 0.73; 95% CI 0.62-0.85; P < 0.0001), hospitalization for unstable angina (RR 0.69; 95%CI 0.54-0.88; P = 0.003), coronary and noncoronary revascularization (RR 0.82; 95%CI 0.73-0.92; P = 0.0007) and (RR 0.41; 95%CI 0.18-0.96; P = 0.04), respectively. However, BA increased the risk of gout (RR 1.55; 95% CI 1.26-1.90; P < 0.0001), hyperuricemia (RR 1.94; 95% CI 1.73-2.18; P < 0.00001) and worsening renal function (RR 1.34; 95%CI 1.21-1.48; P < 0.00001). BA also reduced LDL-C (MD -22.38%; 95% CI -25.94 to - 18.82; P < 0.00001) and total cholesterol (MD -13.86%; 95% CI -15.82 to -11.91; P < 0.0000) compared with placebo. Bempedoic acid is an addition to the arsenal of lipid-lowering drugs used in patients that are statin intolerant or need additional lipid-lowering therapy.
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Association between e-cigarette use and myocardial infarction: a systematic review and meta-analysis. Egypt Heart J 2023; 75:97. [PMID: 38032522 PMCID: PMC10689622 DOI: 10.1186/s43044-023-00426-6] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/14/2023] [Accepted: 11/26/2023] [Indexed: 12/01/2023] Open
Abstract
BACKGROUND The popularity of e-cigarettes has risen dramatically over the last few years, particularly among the younger population. Although the use of combustible cigarettes has established evidence to be associated with the development of several adverse cardiopulmonary diseases, the investigations regarding the prospective long-term effects of e-cigarette use on the cardiovascular system have just begun. We set to investigate if there is an association between the history of MI and e-cigarette use among smokers and non-smokers? METHODS The current review aims to assess the association of myocardial infarction with e-cigarette consumption. PubMed, Google Scholar, and Cochrane Central Register of Controlled Trials (CENTRAL) were queried up to October 2022 to identify articles assessing the incidence of myocardial infarction among e-cigarette users. Data were meta-analyzed using a random-effects model to derive odds ratios (OR) and 95% confidence intervals. RESULTS Nine studies involving 984,764 patients were included. The mean age of e-cigarette smokers was less than the controls, and female participants dominated the sample size. E-cigarette users were associated with increased odds of MI than non-users [OR = 1.44; 95% CI (1.22, 1.74); P < 0.0001]. Dual users were also associated with increased odds of MI with large effect when compared to non-users [OR = 4.04; 95% CI (3.40, 4.81); P < 0.00001]. CONCLUSIONS Dual use is associated with an increased risk of MI than e-cigarette use only. Similarly, dual and solely e-cigarette consumption patterns of nicotine delivery are at a higher risk of MI than non-smokers.
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Revolutionizing the effect of Azadirachta indica extracts on edema induced changes in C-reactive protein and interleukin-6 in albino rats: in silico and in vivo approach. EUROPEAN REVIEW FOR MEDICAL AND PHARMACOLOGICAL SCIENCES 2023; 27:5951-5963. [PMID: 37458623 DOI: 10.26355/eurrev_202307_32947] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 07/20/2023]
Abstract
OBJECTIVE The aim of the present study is to determine the in vivo and in silico anti-inflammatory effect of Azadirachta indica (A. indica) in carrageenan-induced rats and its blood biomarkers. A. indica (Neem) is a widely used medicinal plant across the world, especially in Pakistan. Neem leaves have been traditionally used for the synthesis of drugs and treatment of a wide variety of diseases. MATERIALS AND METHODS In this study, sixty albino rats (160-200 g) were divided into 4 groups: control (group I), standard (group II), ethanolic and aqueous (group III and IV) at doses of 50, 100, 200 and 400 mg/kg. RESULTS Ethanolic and aqueous extracts showed maximum inhibition in paw size at the 5th hour (400 mg/kg). Similarly, biomarkers measured, including Interleukin-6 and C-reactive protein, exhibited significant anti-inflammatory activity at the highest dose of 400 mg/kg in both experimental groups but were more distinct in the group treated with ethanolic extracts. Correlation between C-reactive protein (CRP) and inter-leukin-6 (IL-6) showed positive correlation in group III, while negative in group IV. Similarly, positive and negative correlations were observed between CRP biomarkers and paw size in group III and IV, and the same results were also shown in the case of IL-6 and paw size. In molecular docking, the binding energy value of protein CRP and IL-1β with the identified ligands quercetin and nimbosterol showed (-8.2 kcal/mol and -7.7 kcal/mol) the best binding affinity as compared to standard drug diclofenac with -7.0 kcal/mol binding energy respectively. CONCLUSIONS In conclusion, in silico and in vivo analysis revealed that the extracts of A. indica leaves can be used as an effective drug to manage inflammation.
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Monkeypox Virus and Other Emerging Outbreaks: An Overview and Future Perspective. INQUIRY : A JOURNAL OF MEDICAL CARE ORGANIZATION, PROVISION AND FINANCING 2023; 60:469580231175437. [PMID: 37190997 DOI: 10.1177/00469580231175437] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/17/2023]
Abstract
Monkeypox (MPX) is a zoonotic disease caused by the MPX virus from the poxviridae family of orthopoxviruses. Typically, endemic in central and west Africa, it has now become a matter of concern since cases have been reported in non-endemic countries around mid-June 2022, especially in the European region, with the transmission not related to travel. The diagnosis is made by PCR testing of the skin lesions. Even though treatment is symptomatic, antiretrovirals, such as tecovirimat, are used in severe cases. Vaccination with second and third generation vaccines is approved for prophylaxis in high risk individuals. Unfortunately, these options of treatment and prevention are only available in high income countries at the moment. This review, through a thorough literature search of articles from 2017 onward, focuses on epidemiology, clinical manifestations, challenges, treatment, prevention and control of MPX virus and how they can be corelated with other viral outbreaks including COVID-19, Acute Hepatitis of unknown origin, Measles and Dengue, to better predict and therefore prevent its transmission. The previous COVID-19 pandemic increased the disease burden on healthcare infrastructure of low-middle income countries, therefore, this recent MPX outbreak calls for a joint effort from healthcare authorities, political figures, and NGOs to combat the disease and prevent its further spread not only in high income but also in middle- and low-income countries.
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Efficacy of pentamidine-loaded chitosan nanoparticles as a novel drug delivery system for Leishmania tropica. Trop Biomed 2022; 39:511-517. [PMID: 36602209 DOI: 10.47665/tb.39.4.003] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/31/2022]
Abstract
The present study compares the in vitro effects of nanoparticles loaded pentamidine drug and conventional pentamidine on Leishmania tropica. Herein, pentamidine-loaded chitosan nanoparticles (PTN-CNPs) have been synthesized through an ionic gelation method with sodium tripolyphosphate (TPP). Next, the physical characteristics of PTN-CNPs were determined through the surface texture, zeta potential, in vitro drug release, drug loading content (DLC), and encapsulation efficacy (EE) and compared its efficacy with free pentamidine (PTN) drug against promastigotes and axenic amastigotes forms of L. tropica in vitro. The PTN-CNPs displayed a spherical shape having a size of 88 nm, an almost negative surface charge (-3.09 mV), EE for PTN entrapment of 86%, and in vitro drug release of 92% after 36 h. In vitro antileishmanial activity of PTN-CNPs and free PTN was performed against Leishmania tropica KWH23 promastigote and axenic amastigote using 3-(4, 5- dimethylthiazol-2-yl)-2, 5-diphenyletetrazolium bromide (MTT) assay. It was observed that the effect of PTN-CNPs and free PTN on both forms of the parasite was dose and time dependent. Free PTN presented low efficacy even at higher dose (40 µg/ml) with 25.6 ± 1.3 and 26.5 ±1.4 mean viability rate of the promastigotes and axenic amastigotes, respectively after 72 hrs incubation. While PTN-CNPs showed strong antileishmanial effects on both forms of parasite with 16 ± 0.4 and 19 ± 0.7 mean viability rate at the same higher concentration (40 µg/ml) after 72 hrs incubation. Half maximal inhibitory concentration (IC50) values of PTN-CNPs toward promastigotes and amastigotes were obtained as 0.1375 µg/ml and 0.1910 µg/ml, respectively. In conclusion, PTN-CNPs effectively inhibited both forms of the L. tropica; however, its effect was more salient on promastigotes. This data indicates that the PTN-CNPs act as a target drug delivery system. However, further research is needed to support its efficacy in animal and human CL.
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Development of Scalable Stem Cell Cultivation Processes in Bioreactors. CHEM-ING-TECH 2022. [DOI: 10.1002/cite.202255185] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/07/2022]
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Antimicrobial prescribing trends and appropriateness in a tertiary teaching hospital in Malaysia. Int J Infect Dis 2020. [DOI: 10.1016/j.ijid.2020.09.263] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/25/2022] Open
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Aptamer-based biosensors: a novel toolkit for early diagnosis of cancer. MATERIALS TODAY CHEMISTRY 2019. [DOI: 10.1016/j.mtchem.2019.04.005] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 02/05/2023]
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Medical Malpractice in Bronchoscopy: Failure to Diagnose and Treat Remains the Top Reason for Litigation. A72. ADVANCES IN INTERVENTIONAL PULMONARY 2019. [DOI: 10.1164/ajrccm-conference.2019.199.1_meetingabstracts.a2363] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 09/02/2023]
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Resistant Cytomegalovirus Infection in Solid-organ Transplantation: Single-center Experience, Literature Review of Risk Factors, and Proposed Preventive Strategies. Transplant Proc 2018; 50:3756-3762. [PMID: 30586840 DOI: 10.1016/j.transproceed.2018.02.091] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/28/2018] [Accepted: 02/17/2018] [Indexed: 01/21/2023]
Abstract
BACKGROUND Cytomegalovirus (CMV) infection causes morbidity and mortality in solid-organ transplant recipients. Drug-resistant CMV is an emerging problem with poor survival outcomes and limited therapeutic options. In this study we comprehensively address the issue of drug resistance in CMV when compared with standard therapies, such as ganciclovir (GCV) and foscarnet. METHODS We conducted a retrospective review of adult patients diagnosed with CMV after solid-organ transplant at our center between 2013 and 2017, and identified 7 resistant CMV cases. To study risk factors in the published literature, we performed an extensive database search. RESULTS All patients had documented UL97 mutations, and 3 patients harbored both UL97 and UL54 mutations. For cases with increasing viral load or failure to achieve clinical improvement despite optimal therapy, genetic resistance testing was carried out. Patients received GCV and foscarnet combination therapy. As an adjunct, CMV immunoglobulin, cidofovir, and leflunomide were added. Risk factors, including donor+/recipient- serostatus, persistent high viral replication, prolonged therapeutic GCV exposure (>2.5 months), and allograft rejection, were assessed. CONCLUSION Patients at risk, especially those with D+/R- serostatus, should be judiciously monitored for resistance. Prolonged intravenous GCV exposure increases the risk for development of drug resistance. Therefore, precise guidelines are required for prevention of long-term GCV/VGCV exposure. Investigation regarding interferon-gamma release assay and adoptive transfer of T cells in diagnosed CMV patients is warranted to improve future prophylactic and management strategies against CMV, with a potential to reduce the requirement for available toxic antiviral drugs.
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Microbiological variation amongst fresh and minimally processed vegetables from retail establishers - a public health study in Pakistan. FOOD RESEARCH 2017. [DOI: 10.26656/fr.2017.6.060] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/12/2022] Open
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Effect of supplementation of prebiotic mannan-oligosaccharides and probiotic mixture on growth performance of broilers subjected to chronic heat stress. Poult Sci 2012; 91:2235-40. [DOI: 10.3382/ps.2012-02182] [Citation(s) in RCA: 222] [Impact Index Per Article: 18.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/29/2022] Open
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EXACT SOLUTIONS FOR OSCILLATING MOTION OF A SECOND-GRADE FLUID ALONG AN EDGE WITH MIXED BOUNDARY CONDITIONS. CHEM ENG COMMUN 2012. [DOI: 10.1080/00986445.2011.636849] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/28/2022]
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6611 Hepatocellular carcinoma: a retrospective analysis of 276 cases. EJC Suppl 2009. [DOI: 10.1016/s1359-6349(09)71332-1] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/20/2022] Open
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Renal artery stenosis: clinical picture, frequency, and management. JOURNAL OF THE SOUTH CAROLINA MEDICAL ASSOCIATION (1975) 1998; 94:306-9. [PMID: 9689782] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 02/08/2023]
Abstract
Our review has demonstrated a high prevalence of RAS in the elderly population, particularly the group affected by atherosclerosis, as well as disclosing the potential benefits of early diagnosis, treatments, and the associated morbidity/mortality of each corrective intervention.
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Abstract
The BamHI restriction-modification system contains a third gene, bamHIC, which positively regulates bamHIR. Similar small genes from other systems were tested in vivo for their ability to cross-complement. C.BamHI protein was identified, purified, and used to raise polyclonal antibodies. Attempts to detect other C proteins in cell extracts by cross-reactivity with C.BamHI antibodies proved unsuccessful.
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Purification and characterization of C.BamHI, a regulator of the BamHI restriction-modification system. Gene X 1995; 157:227-8. [PMID: 7607495 DOI: 10.1016/0378-1119(94)00698-r] [Citation(s) in RCA: 14] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/26/2023] Open
Abstract
The bamHIC gene, controlling the BamHI restriction-modification (R-M) system can functionally be replaced by providing pvuIIC or smaIC in trans. C.BamHI, the protein product encoded by bamHIC, has been purified and shown to bind a 345-bp DNA fragment within the BamHI R-M system.
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BseRI a novel restriction endonuclease from a Bacillus species which recognizes the sequence 5'...GAGGAG...3'. Nucleic Acids Res 1993; 21:3585. [PMID: 8346041 PMCID: PMC331471 DOI: 10.1093/nar/21.15.3585] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/30/2023] Open
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A gene required for very short patch repair in Escherichia coli is adjacent to the DNA cytosine methylase gene. J Bacteriol 1990; 172:4214-21. [PMID: 2198248 PMCID: PMC213244 DOI: 10.1128/jb.172.8.4214-4221.1990] [Citation(s) in RCA: 93] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/30/2022] Open
Abstract
Deamination of 5-methylcytosine in DNA results in T/G mismatches. If unrepaired, these mismatches can lead to C-to-T transition mutations. The very short patch (VSP) repair process in Escherichia coli counteracts the mutagenic process by repairing the mismatches in favor of the G-containing strand. Previously we have shown that a plasmid containing an 11-kilobase fragment from the E. coli chromosome can complement a chromosomal mutation defective in both cytosine methylation and VSP repair. We have now mapped the regions essential for the two phenotypes. In the process, we have constructed plasmids that complement the chromosomal mutation for methylation, but not for repair, and vice versa. The genes responsible for these phenotypes have been identified by DNA sequence analysis. The gene essential for cytosine methylation, dcm, is predicted to code for a 473-amino-acid protein and is not required for VSP repair. It is similar to other DNA cytosine methylases and shares extensive sequence similarity with its isoschizomer, EcoRII methylase. The segment of DNA essential for VSP repair contains a gene that should code for a 156-amino-acid protein. This gene, named vsr, is not essential for DNA methylation. Remarkably, the 5' end of this gene appears to overlap the 3' end of dcm. The two genes appear to be transcribed from a common promoter but are in different translational registers. This gene arrangement may assure that Vsr is produced along with Dcm and may minimize the mutagenic effects of cytosine methylation.
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Abstract
Three peaks of methyltransferase activity specific for MNNG alkylated DNA have been identified from extracts of chemically adapted M. luteus. They are designated as TI to TIII in order to their elution from a Sephadex G-75 column. The first one of these peaks has been purified to homogeneity. TI, is an inducible, unusually salt resistant, heat labile protein which corrects O6-methylguanine in alkylated DNA by the transfer of the O6-alkyl group to a cysteine amino acid in the TI protein. There is a stoichiometric relationship between the loss of O6-methylguanine from the DNA and the production of S-methylcysteine. Partially purified TII & TIII proteins show specificity for O4-alkylthymine and methyl phosphotriesters respectively. The mode of repair by the isolated methyltransferases is similar yet there is no competition for substrate specificity. The apparent molecular weights of TI, TII & TIII proteins are 31Kd, 22Kd, and 13Kd respectively.
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Abstract
Five peaks of DNA glycosylase activity showing a preference for MNNG alkylated DNA have been identified from extracts of adapted M. luteus. They are numerically designated as GI to GV in order of their decreasing molecular weights. The first two of these peaks have been highly purified. GI, is a constitutive heat labile protein, 35% stimulated by the presence of 50 mM NaCl, acts exclusively on 3 MeA residues in alkylated DNA, 60-70% inhibited by the presence of 2 mM free 3MeA and has been designated as 3MeA DNA glycosylase enzyme. GII, which is an inducible protein, is heat stable, 28% inhibited by the presence of 50 mM NaCl, removes 3MeA, 3MeG, 7MeA & 7MeG with different efficiency, and has been designated as 3,7 methylpurine DNA glycosylase enzyme. The rate of release of 3 methylpurines is 30 times that of 7MeG. There is no activity of either enzyme on O2-MeC, O2-MeT, O4-MeT or O6-MeG. The apparent molecular weights of GI and GII proteins are 28 Kd and 22 Kd respectively.
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28
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Abstract
The dcm locus of Escherichia coli K-12 has been shown to code for a methylase that methylates the second cytosine within the sequence 5'-CC(A/T)GG-3'. This sequence is also recognized by the EcoRII restriction-modification system coded by the E. coli plasmid N3. The methylase within the EcoRII system methylates the same cytosine as the dcm protein. We have isolated, from a library of E. coli K-12 DNA, two overlapping clones that carry the dcm locus. We show that the two clones carry overlapping sequences that are present in a dcm+ strain, but are absent in a delta dcm strain. We also show that the cloned gene codes for a methylase, that it complements mutations in the EcoRII methylase, and that it protects EcoRII recognition sites from cleavage by the EcoRII endonuclease. We found no phage restriction activity associated with the dcm clones.
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