Publications by authors named "Ahmed Salman"

193 Publications

Management of Complicated Acute Pancreatitis: The Role of Hub-and-Spoke Model.

J Coll Physicians Surg Pak 2022 May;32(5):575-580

Department of Surgery, North Cumbria Integrated Care, Carlisle, UK.

Objective: To determine the primary and secondary outcomes of patients with complicated acute pancreatitis (CAP) of moderate to severe intensity managed by using the hub-and-spoke model.

Study Design: An observational study.

Place And Duration Of Study: Department of Surgery, North Cumbria Integrated Care, Carlisle, UK, from January 2014 to December 2018.

Methodology: Retrospective analysis of 496 episodes of acute pancreatitis managed in 405 patients was done. Data for demographic features and clinical outcomes were analysed. In patients with recurrent admissions, only index admission was considered for analysis. Complicated acute pancreatitis was defined by using the revised Atlanta classification and included all the acute pancreatitis patients with local and or systemic complications.    Results: The frequency of CAP was 21.7% (88/405). The mean patients' age was 62.11 ± 17.90 years. The intensive therapy unit (ITU) admission rate was 33% (n = 29), whereas the overall intervention rate was 43.2% (n = 38). The in-hospital mortality rate was 10.2% (n = 9), and the overall mortality rate was 14.8% (n = 13). A comparative analysis of clinical outcomes according to the revised Atlanta classification showed that the rate of complications, need for ITU admission, duration of hospital stay, in-hospital mortality and overall mortality were significantly higher in patients with moderately severe AP (MSAP) and severe AP (SAP).

Conclusion: The rate of progression from mild AP to MSAP and SAP remains high. Patients with CAP are at higher risk of ITU admission, prolonged hospital stay, in-hospital mortality and overall mortality. To improve clinical outcomes, the progression of AP to severer forms should be prevented by developing newer strategies, and in cases where complications have already developed, the mortality rate needs to be improved by developing innovative treatment modalities.

Key Words: Acute pancreatitis, Complicated acute pancreatitis, Revised Atlanta classification, Morbidity, Mortality, Survival analysis, Hub and spoke model.
View Article and Find Full Text PDF

Download full-text PDF

Source
http://dx.doi.org/10.29271/jcpsp.2022.05.575DOI Listing
May 2022

The Impact of Outpatient Laboratory Alerting Mechanisms in Patients with AKI.

Kidney360 2021 Oct 14;2(10):1560-1568. Epub 2021 Jul 14.

Harvard Medical School, Boston, Massachusetts.

Background: AKI is an abrupt decrease in kidney function associated with significant morbidity and mortality. Electronic notifications of AKI have been utilized in patients who are hospitalized, but their efficacy in the outpatient setting is unclear.

Methods: We evaluated the effect of two outpatient interventions: an automated comment on increasing creatinine results (intervention I; 6 months; =159) along with an email to the provider (intervention II; 3 months; =105), compared with a control (baseline; 6 months; =176). A comment was generated if a patient's creatinine increased by >0.5 mg/dl (previous creatinine ≤2.0 mg/dl) or by 50% (previous creatinine >2.0 mg/dl) within 180 days. Process measures included documentation of AKI and clinical actions. Clinical outcomes were defined as recovery from AKI within 7 days, prolonged AKI from 8 to 89 days, and progression to CKD with in 120 days.

Results: Providers were more likely to document AKI in interventions I (=0.004; OR, 2.80; 95% CI, 1.38 to 5.67) and II (=0.01; OR, 2.66; 95% CI, 1.21 to 5.81). Providers were also more likely to discontinue nephrotoxins in intervention II (<0.001; OR, 4.88; 95% CI, 2.27 to 10.50). The median time to follow-up creatinine trended shorter among patients with AKI documented (21 versus 42 days; =0.11). There were no significant differences in clinical outcomes.

Conclusions: An automated comment was associated with improved documented recognition of AKI and the additive intervention of an email alert was associated with increased discontinuation of nephrotoxins, but neither improved clinical outcomes. Translation of these findings into improved outcomes may require corresponding standardization of clinical practice protocols for managing AKI.
View Article and Find Full Text PDF

Download full-text PDF

Source
http://dx.doi.org/10.34067/KID.0003312021DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC8785781PMC
October 2021

An infrequent case of adult nasopharynx rhabdomyosarcoma with bony involvement: A case report.

J Pak Med Assoc 2022 Mar;72(3):544-548

Department of Medicine, Dow University of Health Sciences, Ojha Campus, Karachi, Pakistan.

Rhabdomyosarcoma is a rare and highly aggressive malignancy arising from the striated skeletal muscle fibre. It is commonly a childhood tumour and rarely seen in adults. The most predominant part commonly involved is head and neck. We are reporting a rare case of a 54 year old adult male with Rhabdomyosarcoma of nasopharynx with a non specific presentation of weight loss for past four months, fever, a perianal abscess and backache since 10 days. The haematological and biochemical parameters were within normal limits however C reactive protein and erythrocyte sedimentation rate were raised. An MRI for the pelvis, which was done for the extension of perianal abscess, also displayed some heterogeneous marrow signal, which raised the suspicion of some infiltrative process. Later, a bone scan, PET scan, and a biopsy of the nasopharaynx was done. The biopsy confirmed the findings of Rhabdomyosarcoma by showing marked pleomorphism with strong positive desmin and myogin stain. The patient was then referred to the oncology department for further management.
View Article and Find Full Text PDF

Download full-text PDF

Source
http://dx.doi.org/10.47391/JPMA.984DOI Listing
March 2022

Predictors of type-2 diabetes remission following bariatric surgery after a two-year follow up.

Asian J Surg 2022 Mar 4. Epub 2022 Mar 4.

General Surgery Department, Kasralainy School of Medicine, Cairo University, Egypt. Electronic address:

Purpose: Bariatric surgery is evolving as a successful tool for managing morbid obesity and T2DM. This study aimed to identify predictors of diabetes remission after two types of bariatric procedures.

Methods: This prospective study enrolled 172 patients with morbid obesity associated with T2DM scheduled for bariatric surgery. Two laparoscopic bariatric procedures were done; single anastomosis gastric bypass (SAGB, n = 83) and sleeve gastrectomy (LSG, n = 68). Lipid accumulation product index (LAP) and quantitative insulin sensitivity check index (QUICKI) were used to evaluate lipid profile and insulin sensitivity. Two years after surgery condition of DM was evaluated as complete remission (CR), partial remission (PR), or improvement. The primary outcome measure was predictors of diabetes remission.

Results: Two years after surgery, 151 patients were available for evaluation, where 75 patients (49.7%) achieved CR, while PR was found in 36 (23.8%). CR was significantly associated with younger age, shorter duration of DM (p < 0.001, for both), higher C-peptide and GLP-1 levels (p < 0.001 and p = 0.002, respectively), and bypass surgery (p = 0.027). On multivariate analysis, shorter duration of DM, lower BMI, and higher C-peptide levels were the independent factors predicting CR.

Conclusion: Complete remission of T2DM can be achieved in nearly half of the patients two years after SG or SAGB. The duration of diabetes and preoperative BMI and C-peptide levels are the independent factors predicting complete remissions.
View Article and Find Full Text PDF

Download full-text PDF

Source
http://dx.doi.org/10.1016/j.asjsur.2021.12.070DOI Listing
March 2022

Pharmacognostic and phytochemical study of the flowers of Cordia sebestena L.

Pak J Pharm Sci 2022 Jan;35(1):69-76

Department of Pharmacognosy, Faculty of Pharmacy and Pharmaceutical Sciences, University of Karachi, Karachi, Pakistan.

The present study shows the pharmacognostic and phytochemical studies on the flowers of Cordia sebestena L. belongs to the family Boraginaceae. C. sebestena L. is found primarily in tropical and subtropical regions of the American, Asian and African continents. Though it is an important plant, until date no pharmacognostic work is found on its parts such as flowers. Various organoleptic characters were recorded by macroscopic study. Microscopic study of the flowers were also conducted which shows the presence of fibers, calcium oxalate crystals and multiple types of trichomes, along with fluorescence analysis. The present study also deals with the Fourier transform infrared spectroscopic analysis of C. sebestena L. FT-IR spectra revealed the presence of C-H, C=C, C-N, C-O and aromatic groups. Chemical composition of the hexane extract of the flowers of C. sebestena L. was detected through GC-MS and spectrum achieved through GC-MS were correlated with the database of National Institute of Standards and Technology (NIST) which comprise of beyond 62000 outlines of the mass spectrum. GC-MS analysis of n-hexane extract shown the existence of Retinoic acid, lupeol, β-sitosterol, stigmasterol, hexadecanoic acid along with fatty acids, esters, alkaloids and alcohols. These pharmacognostic and phytochemical studies can be valuable towards giving reliable proof of the quality of the plant which can benefit health professionals and herbal medicine manufacturers.
View Article and Find Full Text PDF

Download full-text PDF

Source
January 2022

An Electrostatic MEMS Roll-Pitch Rotation Rate Sensor with In-Plane Drive Mode.

Sensors (Basel) 2022 Jan 18;22(3). Epub 2022 Jan 18.

Si-Ware Systems, Heliopolis, Cairo 11361, Egypt.

In this paper, we presented a novel electrostatic Roll/Pitch MEMS gyroscope with in-plane drive mode and out-of-plane sense mode. The proposed structure is developed based on a tuning fork gyroscope with decoupled sense mass on each tine that control the sense out-of-plane frequency. A multi-height deep reactive ion etching (DRIE) fabrication process was utilized to achieve and enhance decoupling between the drive and sense modes. We presented our design methodology followed by an analytical and finite element (FEM) model. Our experimental results showed a good match between the analytical model and those obtained experimentally, from the drive and sense oscillation frequencies. Our characterization setup used a custom made application specific integrated circuit (ASIC) for characterization and was able to achieve ARW of 0.2 deg/rt-h, a bias instability 5.5 deg/h, and scale factor non-linearity (SFNL) 156 ppm FS.
View Article and Find Full Text PDF

Download full-text PDF

Source
http://dx.doi.org/10.3390/s22030702DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC8839371PMC
January 2022

The Kidney Failure Risk Equation Score and CKD Care Delivery Measures: A Cross-sectional Study.

Kidney Med 2022 Jan 15;4(1):100375. Epub 2021 Oct 15.

Division of Renal Medicine, Brigham and Women's Hospital, Harvard Medical School, Boston, MA.

Rationale & Objective: The 4-variable kidney failure risk equation (KFRE) allows for the prediction of chronic kidney disease (CKD) progression using age, sex, estimated glomerular filtration rate, and urine albumin/creatinine ratio. Electronic health records enable KFRE auto-calculation, and registries allow population-level application. We assessed whether 2-year KFRE score categories are associated with CKD care metrics.

Study Design: Cross-sectional cohort.

Setting & Participants: This study included individuals with CKD in March 2020 who were receiving care within the Partners HealthCare system in Massachusetts.

Outcomes: The presence of sufficient data to calculate the KFRE and, among those with a KFRE score, performance on CKD clinical care metrics, including (1) prescription of angiotensin-converting enzyme inhibitor or angiotensin receptor blocker; (2) blood pressure at goal (<140/90 mm Hg) based on clinic measurements; (3) composite metric of hepatitis B virus immunity; (4) composite metric of referral, evaluation, or waitlist status for kidney transplantation; (5) advance directive documentation; (6) yearly influenza vaccination; and (7) pneumonia vaccination.

Analytical Approach: Multivariable logistic regression analysis was used to analyze the association of KFRE score category with CKD care metrics.

Results: Of 61,546 patients, 18,272 (30%) had auto-calculated 2-year KFRE scores; the remaining patients lacked KFRE scores because of absent albuminuria assessment. Individuals with a KFRE score were more likely to have a primary care provider or nephrologist. Among patients with 2-year KFRE scores, high-risk patients had increased odds of completing advance directives (OR, 1.52; 95% CI, 1.07-2.17), while low-risk patients had decreased odds of influenza vaccination (OR, 0.85; 95% CI, 0.75-0.97). Patients with moderate- and high-risk KFRE scores had lower odds of having blood pressure at goal (OR, 0.77; 95% CI, 0.61-0.96 and OR, 0.63; 95% CI, 0.44-0.88, respectively).

Limitations: Albuminuria data may have been assessed outside of the Partners system.

Conclusions: A higher-risk KFRE score is associated with the delivery of some but not all CKD care measures. An opportunity exists to improve albuminuria measurement.
View Article and Find Full Text PDF

Download full-text PDF

Source
http://dx.doi.org/10.1016/j.xkme.2021.08.010DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC8767093PMC
January 2022

Secondary Hyperparathyroidism Before and After Bariatric Surgery: a Prospective Study with 2-Year Follow-Up.

Obes Surg 2022 04 20;32(4):1141-1148. Epub 2022 Jan 20.

General Surgery Department, Kasralainy School of Medicine, Cairo University, Cairo, Egypt.

Purpose: Secondary hyperparathyroidism (SHPT) is linked to obesity. Bariatric surgery may be associated with calcium and vitamin D deficiencies leading to SHPT. This study aimed to detect the prevalence of SHPT before and after bariatric surgery.

Methods: This prospective study assessed the prevalence of SHPT after sleeve gastrectomy (SG, n = 38) compared to one-anastomosis gastric bypass (OAGB, n = 86). All patients were followed up for 2 years. Bone mineral density (BMD) was assessed using dual-energy X-ray absorptiometry.

Results: Of the 124 patients, 71 (57.3%) were females, and 53 (42.7%) were males, with a mean age of 37.5 ± 8.8 years. Before surgery, 23 patients (18.5%) suffered from SHPT, and 40 (32.3%) had vitamin D deficiency. The prevalence of SHPT increased to 29.8% after 1 year and 36.3% after 2 years. SHPT was associated with lower levels of vitamin D and calcium and higher reduction of BMD in the hip but not in the spine. After 2 years, SHPT was associated with a significantly lower T-score in the hip. SHPT and vitamin D deficiency were significantly more common in patients subjected to OAGB compared to SG (p = 0.003, and p < 0.001, respectively). There is a strong negative correlation between vitamin D levels and parathormone levels before and after surgery.

Conclusion: Prevalence of SHPT is high in obese patients seeking bariatric surgery, especially with lower vitamin D levels. Bariatric surgery increases the prevalence of SHPT up to 2 years. Gastric bypass is associated with a higher risk of developing SHPT compared to SG.
View Article and Find Full Text PDF

Download full-text PDF

Source
http://dx.doi.org/10.1007/s11695-022-05902-7DOI Listing
April 2022

Autoimmune Hemolytic Anemia Exacerbation Associated With COVID-19 Infection and Markedly Elevated Inflammatory Markers.

Cureus 2021 Dec 14;13(12):e20416. Epub 2021 Dec 14.

Internal Medicine, Regional Medical Center, Anniston, USA.

The association between previously diagnosed autoimmune hemolytic anemia and exacerbations due to coronavirus disease 2019 (COVID-19) infection is a rare phenomenon that is not well understood. In this case, we present a 68-year-old female with a past medical history significant for systemic lupus erythematosus (SLE), splenectomy, and autoimmune hemolytic anemia (AIHA) since childhood that had been very well controlled with only one previous exacerbation. This patient's chief complaint and clinical symptoms at admission were related to hemolytic anemia and not active COVID-19 infection. This case report reveals a possible association between the hyperinflammatory syndrome caused by COVID-19 and the exacerbation of previously well-controlled autoimmune diseases.
View Article and Find Full Text PDF

Download full-text PDF

Source
http://dx.doi.org/10.7759/cureus.20416DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC8759712PMC
December 2021

Nutritional Complications After Laparoscopic Roux-en-Y Gastric Bypass and One-Anastomosis Gastric Bypass: A Comparative Systematic Review and Meta-Analysis.

Cureus 2022 Jan 11;14(1):e21114. Epub 2022 Jan 11.

General and Laparoscopic Surgery, El Zaitoun Specialized Hospital, Cairo, EGY.

A systematic review and meta-analysis were carried out involving studies that compared the nutritional complications of Roux-en-Y gastric bypass (RYGB) and one-anastomosis gastric bypass (OAGB); these included the incidence of malnutrition as well as deficiencies of other nutritional elements, such as total protein, albumin, calcium and iron. A comprehensive search strategy was implemented in PubMed, Embase, and the Cochrane Library. Effect sizes included the pooled odds ratios (ORs) and 95% confidence intervals (95% CIs), as well as mean differences (MDs) and 95% CIs of the percentage total weight loss (%TWL) and excess weight loss percentage (%EWL). Thirteen studies were included (12,964 patients, 66.27% females, 53.82% underwent OAGB). At the longest follow-up period (≥3 years), OAGB was associated with significantly higher %TWL (MD=5.41%, 95%CI, 1.52 to 9.29) and %EWL (MD=13.81%, 95%CI, 9.60 to 18.02) compared to RYGB. However, OAGB procedures were associated with malnutrition (OR=3.00, 95%CI, 1.68 to 5.36, p<0.0001), hypoalbuminemia (OR=2.38, 95%CI, 1.65 to 3.43, p<0.0001), hypoproteinemia (OR=1.85, 95%CI, 1.09 to 3.14, p=0.022), anemia (OR=1.38, 95%CI, 1.08 to 1.77, p=0.011), and hypocalcemia (OR=1.78, 95%CI, 1.01 to 3.12, p=0.046). On subgroup analyses, the proportions of anemia and hypoalbuminemia remained significantly higher at longer follow-up periods and in studies published in Asia. Despite the favorable weight loss profile, the unfavorable nutritional consequences of OAGB merits further investigations to explore the malabsorptive element, ethnic variation, and the role of biliopancreatic limb length.
View Article and Find Full Text PDF

Download full-text PDF

Source
http://dx.doi.org/10.7759/cureus.21114DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC8752406PMC
January 2022

Ursodeoxycholic acid for the prevention of gall stones after laparoscopic sleeve gastrectomy: a prospective controlled study.

Surg Endosc 2022 Jan 12. Epub 2022 Jan 12.

General Surgery Department, Kasralainy School of Medicine, Cairo University, Cairo, Egypt.

Background: Obesity is a risk factor for cholelithiasis. Besides, rapid weight loss after bariatric surgery upsurges the rate of cholelithiasis and acute cholecystitis. This study aimed to compare gallstone development frequency after LSG under ursodeoxycholic acid (UDCA) prophylaxis.

Methods: This prospective controlled study included 332 patients scheduled for LSG randomized to receive 500 mg UDCA daily for 12 months (UDCA Group) or no treatment (Control Group). Ultrasonography was done 6 and 12 months after surgery to detect gallstones. Cholecystectomy was done for complicated cases of cholelithiasis.

Results: Seventy-one patients were lost to follow-up, and 3 developed severe adverse effects of UDCA and excluded. Data are presented for 130 patients in the UDCA group and 128 in the Control group. Collectively, 11 patients (8.5%) of the UDCA group and 41 (32.0%) of the Control group developed gall stones during the first postoperative year (p < 0.001). Cholecystectomy was indicated in 3 patients (2.3%) of the UDCA group and 9 (7.0%) of the Control group (p = 0.072). On multivariate analysis, higher BMI, dyslipidemia, and lacking UDCA prophylaxis were the independent factors significantly associated with stone development. Also, stone development was associated with higher weight loss after 6 and 12 months.

Conclusion: UDCA 500 mg once daily for 12 months after LSG is effective in reducing gallstone formation at 1 year. UDCA administration reduced the frequency of cholecystectomies from 7 to 2.3%. High BMI and dyslipidemia are the independent preoperative factors significantly associated with stone development.
View Article and Find Full Text PDF

Download full-text PDF

Source
http://dx.doi.org/10.1007/s00464-021-08980-3DOI Listing
January 2022

Effects of Gastric Bypass and Sleeve Gastrectomy on Bone Mineral Density and Bone Turnover Markers: A Systematic Review and Meta-Analysis.

World J Surg 2022 Apr 10;46(4):865-875. Epub 2022 Jan 10.

Gastroenterology and Hepatology Department, National Hepatology and Tropical Medicine Research Institute, Cairo, Egypt.

Background: There is a growing interest in the post-operative bone-related effects of bariatric surgery. However, little is known about the comparative effects of the most commonly performed bariatric procedures, namely Roux-en-Y gastric bypass (RYGB) and sleeve gastrectomy (SG).

Objectives: To systematically assess the differences in areal bone mineral density (aBMD) and biochemical and hormonal markers of bone metabolism among patients undergoing RYGB and SG.

Methods: We conducted a systematic review and meta-analysis of studies aBMD at different sites, as well as bone-specific alkaline phosphatase (BALP), 25-OH-vitamin D, calcium and parathyroid hormone (PTH) after RYGB and SG.

Results: Fourteen studies were included (717 patients, 50.63% in the RYGB arm). Based on data collected at 1 year, 2 years and > 2 years, there were no significant differences in aBMD measurements at the total hip, lumbar spine, femoral neck, and the whole body with no statistical heterogeneity among different comparisons. Patients in the RYGB group showed significantly higher concentrations of BALP at 1 year (SMD = 0.52, 95%CI, 0.23-0.81, p = 0.0004) and PTH at > 2 years of follow-up (SMD = 0.68, 95%CI, 0.31-1.05, p = 0.0003) compared to the SG group.

Conclusion: There were no significant differences in aBMD measurements at the hip, lumbar spine, femoral neck, and the total body following RYGB and SG procedures. However, BALP and PTH concentrations were significantly higher after RYGB surgeries compared to SG. Attention should be paid to patients undergoing RYGB to prevent the expected skeletal fragility over time.
View Article and Find Full Text PDF

Download full-text PDF

Source
http://dx.doi.org/10.1007/s00268-021-06429-1DOI Listing
April 2022

Glycated haemoglobin association with severity of thrombus burden in non-diabetic versus diabetic patients with ST-elevation myocardial infarction.

J Pak Med Assoc 2021 Oct;71(10):2355-2358

Department of Public Health, The Shaheed Zulfikar Ali Bhutto Institute of Science and Technology, Karachi, Pakistan.

Objective: To determine and compare the relationship between glycated haemoglobin level on admission and the angiographic thrombus burden in diabetic and non-diabetic patients with ST-segment elevation myocardial infarction.

Methods: The cross-sectional study was conducted at the National Institute of Cardiovascular Diseases, Karachi, from June 2018 to July 2019, and comprised patients presenting with ST-elevation myocardial infarction. Demographic details and self-reported duration of diabetes was recorded. The thrombus burden was assessed on angiography classifying 0 = no thrombus, 1 = possible thrombus, 2 = small thrombus, 3 = moderate thrombus, 4 = large thrombus, and 5 = total occlusion. The data was analysed using SPSS 21.

Results: Of the 212 patients, 173(81.6%) were men, and 75(35.4%) had body mass index ≥30kg/m2. The overall mean age of the sample was 54.62±11.75 years. Known diabetic cases were 82(38.7%) and 20(24.4%) were insulin-dependent. Mean glycated haemoglobin level was 7.18±2.03% and 96(45.3%) patients had the critical value >6.5%. Pre-procedure thrombus score in 118(55.7%) patients was 3 and 4 and 57(26.9%) had total occlusion. A significant relationship between glycated haemoglobin level and thrombus score was found in the overall sample as well as in diabetic and non-diabetic groups (p<0.001).

Conclusions: Increased glycated haemoglobin level was found to have a positive correlation with thrombus score in both diabetic and non-diabetic patients.
View Article and Find Full Text PDF

Download full-text PDF

Source
http://dx.doi.org/10.47391/JPMA.02-445DOI Listing
October 2021

The Impact of Drain and Reinforcement on the Outcomes of Bariatric Surgery: A Prospective Study.

Cureus 2021 Dec 13;13(12):e20382. Epub 2021 Dec 13.

General Surgery, Sunderland Royal Hospital, Sunderland, GBR.

Purpose We aimed to investigate the impact of reinforcement and abdominal drains on the outcome of laparoscopic sleeve gastrectomy (LSG). Methods The present study was a prospective study that included obese patients scheduled to undergo LSG. Patients were assigned to receive drain, reinforcement, or both according to the surgeon's preference and followed up for one month after surgery. The present study's primary outcome was the identification of the association between intraoperative drain/reinforcement and the incidence of postoperative complications. Results A total of 125 (20.3%) patients received intraoperative drains. The proportion of postoperative morbidity was comparable between the drain and non-drain groups (3.2% versus 1.6%; p = 0.25). Patients in the drain group had similar incidence of blood transfusion (2.4% versus 1.7% in non-drain group; p = 0.43) and postoperative leakage (0.8% versus 0.2% in non-drain group; p = 0.36). The incidences of blood transfusion (p = 0.56) and reoperation (p = 0.98) were comparable between the drain and non-drain groups. There were no statistically significant differences between the drain and non-drain groups regarding postoperative mortality and wound infection (p > 0.05). On the other hand, 440 (71.3%) patients received reinforcement. The proportion of postoperative morbidity was comparable between the reinforcement and non-reinforcement groups (1.6% versus 2.8%, p = 0.07). Patients in the reinforcement group were less likely to develop postoperative bleeding (0.7% versus 4% in the non-reinforcement group; p = 0.004), while no significant difference was detected in terms of postoperative leakage (p = 0.33) and in-hospital mortality. Conclusion In conclusion, abdominal drainage did not reduce the complications of LSG patients. Reinforcement has some role in controlling the bleeding but not leaks. Both techniques did not significantly impact the mortality rate. In the future, additional, large randomized trials are needed to examine the gastrointestinal-related quality of life.
View Article and Find Full Text PDF

Download full-text PDF

Source
http://dx.doi.org/10.7759/cureus.20382DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC8673688PMC
December 2021

Controlled Study of Decision-Making Algorithms for Kidney Replacement Therapy Initiation in Acute Kidney Injury.

Clin J Am Soc Nephrol 2022 02 15;17(2):194-204. Epub 2021 Dec 15.

Division of Renal Medicine, Brigham and Women's Hospital, Harvard Medical School, Boston, Massachusetts.

Background And Objectives: AKI requiring KRT is associated with high mortality and utilization. We evaluated the use of an AKI Standardized Clinical Assessment and Management Plan (SCAMP) on patient outcomes, including mortality, hospital length of stay, and intensive care unit length of stay.

Design, Setting, Participants, & Measurements: We conducted a 12-month controlled study in the intensive care units of a large academic tertiary medical center. We alternated use of the AKI-SCAMP with use of a "sham" control form in 4- to 6-week blocks. The primary outcome was risk of inpatient mortality. Prespecified secondary outcomes included 30- and 60-day mortality, hospital length of stay, and intensive care unit length of stay. Generalized estimating equations were used to estimate the effect of the AKI-SCAMP on mortality and length of stay.

Results: There were 122 patients in the AKI-SCAMP group and 102 patients in the control group. There was no significant difference in inpatient mortality associated with AKI-SCAMP use (41% versus 47% control). AKI-SCAMP use was associated with significantly reduced intensive care unit length of stay (mean, 8; 95% confidence interval, 8 to 9 days versus mean, 12; 95% confidence interval, 10 to 13 days; <0.001) and hospital length of stay (mean, 25; 95% confidence interval, 22 to 29 days versus mean, 30; 95% confidence interval, 27 to 34 days; =0.02). Patients in the AKI-SCAMP group were less likely to receive KRT in the context of physician-perceived treatment futility than those in the control group (2% versus 7%; =0.003).

Conclusions: Use of the AKI-SCAMP tool for AKI KRT was not significantly associated with inpatient mortality, but was associated with reduced intensive care unit length of stay, hospital length of stay, and use of KRT in cases of physician-perceived treatment futility.

Clinical Trial Registry Name And Registration Number: Acute Kidney Injury Standardized Clinical Assessment and Management Plan for Renal Replacement Initiation, NCT03368183.

Podcast: This article contains a podcast at https://www.asn-online.org/media/podcast/CJASN/2022_02_07_CJN02060221.mp3.
View Article and Find Full Text PDF

Download full-text PDF

Source
http://dx.doi.org/10.2215/CJN.02060221DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC8823944PMC
February 2022

Therapeutic potential of marine peptides in cervical and ovarian cancers.

Mol Cell Biochem 2022 Feb 2;477(2):605-619. Epub 2021 Dec 2.

State Key Laboratory of Quality Research in Chinese Medicine, Institute of Chinese Medical Sciences, University of Macau, Zhuhai, China.

Cervical and ovarian cancers contribute significantly to female morbidity and mortality worldwide. The current standard of treatment, including surgical removal, radiation therapy, and chemotherapy, offers poor outcomes. There are many side effects to traditional chemotherapeutic agents and treatment-resistant types, and often the immune response is depressed. As a result, traditional approaches have evolved to include new alternative remedies, such as natural compounds. Aquatic species provide a rich supply of possible drugs. The potential anti-cancer peptides are less toxic to normal cells and can attenuate multiple drug resistance by providing an efficacious treatment approach. The physiological effects of marine peptides are described in this review focusing on various pathways, such as apoptosis, microtubule balance disturbances, suppression of angiogenesis, cell migration/invasion, and cell viability. The review also highlights the potential role of marine peptides as safe and efficacious therapeutic agent for the treatment of cervical and ovarian cancers.
View Article and Find Full Text PDF

Download full-text PDF

Source
http://dx.doi.org/10.1007/s11010-021-04306-yDOI Listing
February 2022

Improvement of Coronary Calcium Scores After Bariatric Surgery in People with Severe Obesity.

Obes Surg 2022 02 22;32(2):472-479. Epub 2021 Nov 22.

General Surgery Department, Faculty of Medicine, Cairo University, Giza, Egypt.

Background: Obesity is an independent risk factor for cardiovascular diseases. Coronary artery calcium (CAC) is a direct measure of coronary atherosclerosis. The study investigated the effect of bariatric surgery on CAC scores in people with severe obesity subjected to laparoscopic sleeve gastrectomy (LSG).

Methods: This prospective study included 129 people with severe obesity in two groups; the LSG group (n=74) subjected to surgery and the diet group (n=55), managed by a diet regimen and lifestyle modification. Cardiovascular risk was assessed by Framingham risk score (FRS) and coronary calcium score (CCS) measured by computed tomography initially and after 3 years.

Results: The two groups had a comparable CAD risk before treatment according to FRS or CCS. After treatment, CCS improved significantly in the LSG group (p=0.008) but not in the diet group (p=0.149). There was no correlation between FRS and CCS (r=0.005, p=0.952). Treatment resulted in significant weight reduction and improved fasting blood glucose and lipid profile in the two groups. The change of weight, blood glucose, and HDL, and remission of diabetes mellitus (DM) were significantly higher in the LSG group compared to the diet group.

Conclusion: LSG may reduce the risk of developing future cardiovascular comorbidities evidenced by reducing CAC scores. Significant weight reduction and improvement of cardiovascular risk factors may recommend LSG as a cardioprotective procedure in people with severe obesity.
View Article and Find Full Text PDF

Download full-text PDF

Source
http://dx.doi.org/10.1007/s11695-021-05801-3DOI Listing
February 2022

Analgesic and anti-inflammatory potential of four varieties of bell pepper (Capsicum annum L.) in rodents.

Pak J Pharm Sci 2021 Jul;34(4):1369-1376

Faculty of Pharmacy, Salim Habib University, Karachi, Pakistan.

The aim of study was to evaluate the analgesic and anti-inflammatory activity of four different colored (green, yellow, orange and red) sweet bell peppers (Capsicum annuum L.) available in the local market of Karachi Pakistan. Their 95% ethanol extracts at 200 and 400 mg/kg were prepared and compared with commonly used analgesic (aspirin) and anti-inflammatory agents supporting its traditional use. The analgesic effects of 95% ethanol extracts of Capsicum annum L. were investigated by acetic acid induced writhing, tail immersion and hot plate test. The anti-inflammatory activities were observed using carrageenan-induced edema of hind paw in rats. Animals were divided into 10 groups (n=7): (1) Control (2) CAG 200 (3) CAG 400 (4) CAR 200 (5) CAR 400 (6) CAO 200 (7) CAO 400 (8) CAY 200 (9) CAY 400 and (10) Standard. All the extracts were given orally. Acute toxicity was also determined by increasing the dose till 3000 mg/kg, which showed no evidence of mortality. All extracts of Capsicum significantly increased the hot plate pain threshold, moreover remarkably reduced the carrageenan-induced rat paw edema. Results obtained were compared with corresponding control group revealed that the fresh fruits extract of all four kinds of bell pepper (200 mg/kg and 400mg/kg) possess anti-inflammatory and pain suppressing activities possibly mediated via PG synthesis inhibition.
View Article and Find Full Text PDF

Download full-text PDF

Source
July 2021

Correlation Between Preoperative Gastric Volume and Weight Loss After Laparoscopic Sleeve Gastrectomy.

Int J Gen Med 2021 12;14:8135-8140. Epub 2021 Nov 12.

General Surgery Department, Kasr Al Ainy School of Medicine, Cairo University, Cairo, Egypt.

Purpose: Long-term studies reported inadequate weight loss or weight regain after laparoscopic sleeve gastrectomy (LSG). This study investigated a possible relationship between preoperative gastric volume (GV) measured by CT volumetry and weight loss one year after LSG.

Methods: This prospective study included 120 patients scheduled for LSG. 3D CT gastric volumetry was done before surgery. The weight loss in the first year was serially recorded. The primary outcome measure was the correlation between preoperative GV and postoperative weight loss after one year. The secondary outcomes were the correlation between preoperative GV and other patients' characteristics as age and body mass index (BMI).

Results: Weight and BMI decreased significantly up to 12 months. The percentage of excess weight loss (%EWL) at 6 and 12 months was significantly higher than at three months. Preoperative GV was 1021 ± 253, ranging from 397 to 1543 mL. GV was not related to sex, age, weight, height, postoperative weight, and BMI.

Conclusion: Preoperative gastric volume cannot predict weight loss one year after LSG. It is not correlated with age, sex, or preoperative weight, and BMI.
View Article and Find Full Text PDF

Download full-text PDF

Source
http://dx.doi.org/10.2147/IJGM.S335368DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC8594781PMC
November 2021

Frequency and impact of slow flow / no flow in primary percutaneous coronary intervention.

J Pak Med Assoc 2021 Nov;71(11):2548-2553

College of Physicians and Surgeons of Pakistan, Karachi, Pakistan.

Objective: To determine the frequency of slow/no flow in primary percutaneous coronary intervention, to know the clinical and angiographical predictors of the phenomenon, and to investigate the immediate impact of slow/no flow on haemodnamics.

Method: The cross-sectional study was conducted at the National Institute of Cardiovascular Diseases, Karachi, from June 2018 to July 2019, and comprised patients presenting with ST elevation myocardial infarction who underwent primary percutaneous coronary intervention. Demographic and clinical details of the patients were recorded. The antegrade flow was assessed and determined using the thrombolysis in myocardial infarction criterion. Patients were assessed for the occurrence, predictors and impact of slow/no flow. Data was analysed using SPSS 21.

Results: Of the 559 patients, 441(78.9%) were males. The overall mean age of the sample was 55.86±11.07 years. Angiographical slow/no flow during the procedure occurred in 53 (9.5%) patients, while normal flow was achieved in 506(90.5%). The thrombolysis in myocardial infarction grade in the affected patients was 0 in 10(1.8%), 1 in 15(2.7%), and 2 in 28(5%) patients. Smoking status, prior myocardial infarction, prior heart failure, no history of pre-infarct angina, cerebrovascular disease, New York Heart Association class III or IV, Killip class III or IV, and lower ejection fraction were significant predictors of slow/no flow (p<0.05). The angiographical and procedural predictors were total occlusion of culprit vessel and high thrombus burden (p<0.05). Direct stenting and use of bare metal stents had significantly less chance of developing slow/no flow (p<0.05). The most common immediate impact was hypotension 26(49.1%) and bradyarrhythmia 5(9.4%). However, 2(3.8%) patients developed haemodnamically unstable ventricular tachycardia that resulted in mortality.

Conclusions: Predictors on the basis of history and angiographical features can be taken into account to anticipate the occurrence of slow/no flow phenomenon.
View Article and Find Full Text PDF

Download full-text PDF

Source
http://dx.doi.org/10.47391/JPMA.12-1390DOI Listing
November 2021

Progressive pseudorheumatoid dysplasia misdiagnosed as juvenile idiopathic arthritis: a case report.

J Med Case Rep 2021 Nov 8;15(1):551. Epub 2021 Nov 8.

Department of Paediatrics and Child Health, University of Nairobi, Nairobi, Kenya.

Background: Progressive pseudorheumatoid dysplasia is a rare, autosomal recessively inherited, noninflammatory musculoskeletal disorder caused by mutations occurring in the WNT1-inducible signaling pathway protein 3 gene. Joint cartilage is the primary site of involvement, leading to arthralgia, joint stiffness, contractures, enlargement of the epiphyses and metaphysis of the hand joints, spinal abnormalities, short stature, early osteoarthritis, and osteoporosis. Juvenile idiopathic arthritis is the most common chronic rheumatic disease in childhood and has unknown etiology. Clinical features of progressive pseudorheumatoid dysplasia resemble those of juvenile idiopathic arthritis. Patients with progressive pseudorheumatoid dysplasia are usually misdiagnosed as having juvenile idiopathic arthritis.

Case Presentation: A 13-year-old Yemeni female presented to the rheumatology clinic with a history of joint pains, bone pains, and bone deformity for 7 years. Weight and height were below the third percentiles. There was no tender swelling of metacarpophalangeal and interphalangeal joints, and she presented with scoliosis. Radiographs of the hands revealed the widening of the epiphyses. Progressive pseudorheumatoid dysplasia was suspected, and genetic testing for WNT1-inducible signaling pathway protein 1, 2, and 3 was requested with these findings. A homozygous, likely pathogenic variant was identified in the WNT1-inducible signaling pathway protein 3 gene, which confirmed our diagnosis.

Conclusion: Progressive pseudorheumatoid dysplasia is a rare form of spondyloepimetaphyseal dysplasia and is clinically misdiagnosed as juvenile idiopathic arthritis. It is crucial to consider progressive pseudorheumatoid dysplasia, especially in patients with standard inflammatory markers who are being followed up for juvenile idiopathic arthritis and not improving with antirheumatic intervention.
View Article and Find Full Text PDF

Download full-text PDF

Source
http://dx.doi.org/10.1186/s13256-021-03082-zDOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC8576979PMC
November 2021

Impact of Hypothyroidism on Patients with Hepatocellular Carcinoma Undergoing Liver Transplantation.

Int J Gen Med 2021 16;14:5711-5718. Epub 2021 Sep 16.

Internal Medicine Department, Faculty of Medicine, Cairo University, Cairo, Egypt.

Background: This work endeavored to explore the effect of hypothyroidism on mortality in subjects with HCC who underwent living-donor liver transplantation (LDLT).

Methods: This prospective study included 107 patients with HCC subjected to LDLT, divided into hypothyroid group (n=53) and euthyroid group (n=54). The primary objectives were overall and disease-free survival (DFS).

Results: Euthyroid and hypothyroid groups were comparable in all baseline characteristics except the age of patients. Overall survival (OS) of the whole group at 48 months was 68.8%, while the DFS was 60.2%. On univariate analysis, OS was negatively affected by the older age of the patients (p<0.001) or the donor (p<0.001), hypothyroidism (p=0.008), HBV (p=0.029), larger tumor size (p=0.023), and defective Milan criteria (p=0.022). On multivariate analysis, the age of the patients and donors was the independent factor affecting OS. On univariate analysis, DFS was negatively affected by older age of the patients (p < 0.001) or the donor (p=0.005), hypothyroidism (p=0.005), HBV (p=0.019), larger tumor size (p=0.023), and defective Milan criteria (p=0.020). On multivariate analysis, the age of the patients, thyroid status, and Milan criteria were the independent factors affecting DFS.

Conclusion: Hypothyroidism is a risk factor for worse outcomes in HCC patients after liver transplantation.
View Article and Find Full Text PDF

Download full-text PDF

Source
http://dx.doi.org/10.2147/IJGM.S326315DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC8455075PMC
September 2021

A universal vaccine candidate against Plasmodium vivax malaria confers protective immunity against the three PvCSP alleles.

Sci Rep 2021 09 9;11(1):17928. Epub 2021 Sep 9.

Nuffield Department of Medicine, The Jenner Institute, University of Oxford, The Henry Wellcome Building for Molecular Physiology, Roosevelt Drive, Oxford, OX3 7BN, UK.

Malaria is a highly prevalent parasitic disease in regions with tropical and subtropical climates worldwide. Among the species of Plasmodium causing human malaria, P. vivax is the second most prevalent and the most geographically widespread species. A major target of a pre-erythrocytic vaccine is the P. vivax circumsporozoite protein (PvCSP). In previous studies, we fused two recombinant proteins representing three allelic variants of PvCSP (VK210, VK247 and P. vivax-like) to the mumps virus nucleocapsid protein to enhance immune responses against PvCSP. The objective of the present study was to evaluate the protective efficacy of these recombinants in mice challenged with transgenic P. berghei parasites expressing PvCSP allelic variants. Formulations containing Poly (I:C) or Montanide ISA720 as adjuvants elicited high and long-lasting IgG antibody titers specific to each PvCSP allelic variant. Immunized mice were challenged with two existing chimeric P. berghei parasite lines expressing PvCSP-VK210 and PvCSP-VK247. We also developed a novel chimeric line expressing the third allelic variant, PvCSP-P. vivax-like, as a new murine immunization-challenge model. Our formulations conferred partial protection (significant delay in the time to reach 1% parasitemia) against challenge with the three chimeric parasites. Our results provide insights into the development of a vaccine targeting multiple strains of P. vivax.
View Article and Find Full Text PDF

Download full-text PDF

Source
http://dx.doi.org/10.1038/s41598-021-96986-1DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC8429696PMC
September 2021

Therapeutic potential of marine peptides in glioblastoma: Mechanistic insights.

Cell Signal 2021 11 4;87:110142. Epub 2021 Sep 4.

Department of Pharmacy, Abdul Wali Khan University Mardan 23200, Pakistan. Electronic address:

Glioblastoma multiforme (GBM) is the most common primary malignant brain tumor in humans. It is characterized by excessive cell growth and accelerated intrusion of normal brain tissue along with a poor prognosis. The current standard of treatment, including surgical removal, radiation therapy, and chemotherapy, is largely ineffective, with high mortality and recurrence rates. As a result, traditional approaches have evolved to include new alternative remedies, such as natural compounds. Aquatic species provide a rich supply of possible drugs. The physiological effects of marine peptides in glioblastoma are mediated by a range of pathways, including apoptosis, microtubule balance disturbances, suppression of angiogenesis, cell migration/invasion, and cell viability; autophagy and metabolic enzymes downregulation. Herein, we address the efficacy of marine peptides as putative safe therapeutic agents for glioblastoma coupled with detail molecular mechanisms.
View Article and Find Full Text PDF

Download full-text PDF

Source
http://dx.doi.org/10.1016/j.cellsig.2021.110142DOI Listing
November 2021

Insights on the Regeneration Potential of Müller Glia in the Mammalian Retina.

Cells 2021 07 31;10(8). Epub 2021 Jul 31.

Nuffield Department of Clinical Neuroscience, University of Oxford, Oxford OX3 9DU, UK.

Müller glia, the major glial cell types in the retina, maintain retinal homeostasis and provide structural support to retinal photoreceptors. They also possess regenerative potential that might be used for retinal repair in response to injury or disease. In teleost fish (such as zebrafish), the Müller glia response to injury involves reprogramming events that result in a population of proliferative neural progenitors that can regenerate the injured retina. Recent studies have revealed several important mechanisms for the regenerative capacity of Müller glia in fish, which may shed more light on the mechanisms of Müller glia reprogramming and regeneration in mammals. Mammalian Müller glia can adopt stem cell characteristics, and in response to special conditions, be persuaded to proliferate and regenerate, although their native regeneration potential is limited. In this review, we consider the work to date revealing the regenerative potential of the mammalian Müller glia and discuss whether they are a potential source for cell regeneration therapy in humans.
View Article and Find Full Text PDF

Download full-text PDF

Source
http://dx.doi.org/10.3390/cells10081957DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC8394255PMC
July 2021

Marine peptides in breast cancer: Therapeutic and mechanistic understanding.

Biomed Pharmacother 2021 Oct 16;142:112038. Epub 2021 Aug 16.

Department of Pharmacy, Abdul Wali Khan University Mardan, 23200, Pakistan. Electronic address:

Breast cancer is the most prevalent invasive form of cancer in females and posing a great challenge for overcoming disease burden. The growth in global cancer deaths mandates the discovery of new efficacious natural anti-tumor treatments. In this regard, aquatic species offer a rich supply of possible drugs. Studies have shown that several marine peptides damage cancer cells by a broad range of pathways, including apoptosis, microtubule balance disturbances, and suppression of angiogenesis. Traditional chemotherapeutic agents are characterized by a plethora of side effects, including immune response suppression. The discovery of novel putative anti-cancer peptides with lesser toxicity is therefore necessary and timely, especially those able to thwart multi drug resistance (MDR). This review addresses marine anti-cancer peptides for the treatment of breast cancer.
View Article and Find Full Text PDF

Download full-text PDF

Source
http://dx.doi.org/10.1016/j.biopha.2021.112038DOI Listing
October 2021

Anti-Neutrophil Cytoplasmic Antibodies: To Care or Not to Care.

Cureus 2021 Aug 11;13(8):e17094. Epub 2021 Aug 11.

Internal Medicine, Baylor College of Medicine, Houston, USA.

Anti-neutrophil cytoplasmic antibodies (ANCA) associated vasculitis is a disease process with a wide range of presentations, from asymptomatic or minimally symptomatic disease with positive laboratory testing, to florid acute end-organ damage. Consensus has not been established as to the frequency and/or protocol by which ANCA testing should be repeated. We present the case of a 53-year-old woman who initially came to medical attention with persistent dyspnea and pulmonary infiltrates presumed to be due to acute exacerbation of chronic diastolic congestive heart failure. Extensive infectious disease testing was negative, but ANCA testing was positive. However, because antinuclear antibody (ANA) interference in the original sample rendered the test result difficult to interpret, the test was not repeated. The patient presented eight months after the initial hospitalization with acute hypoxemic respiratory failure requiring intubation, with an ANCA titer of 1:1280 with a negative ANA titer, and renal biopsy-proven severe crescentic glomerulonephritis. In the discussion of our case, we review the importance of interpreting ANCA testing in the correct clinical context. The ANCA laboratory testing requires cautious interpretation, and diagnosed ANCA-associated vasculitis (AAV) requires vigilance for prompt and proactive treatment.
View Article and Find Full Text PDF

Download full-text PDF

Source
http://dx.doi.org/10.7759/cureus.17094DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC8356677PMC
August 2021

A Deep Convolutional Neural Network Model for Improving WRF Simulations.

IEEE Trans Neural Netw Learn Syst 2021 Aug 10;PP. Epub 2021 Aug 10.

Advancements in numerical weather prediction (NWP) models have accelerated, fostering a more comprehensive understanding of physical phenomena pertaining to the dynamics of weather and related computing resources. Despite these advancements, these models contain inherent biases due to parameterization of the physical processes and discretization of the differential equations that reduce simulation accuracy. In this work, we investigate the use of a computationally efficient deep learning (DL) method, the convolutional neural network (CNN), as a postprocessing technique that improves mesoscale Weather Research and Forecasting (WRF) one-day simulation (with a 1-h temporal resolution) outputs. Using the CNN architecture, we bias-correct several meteorological parameters calculated by the WRF model for all of 2018. We train the CNN model with a four-year history (2014-2017) to investigate the patterns in WRF biases and then reduce these biases in simulations for surface wind speed and direction, precipitation, relative humidity, surface pressure, dewpoint temperature, and surface temperature. The WRF data, with a spatial resolution of 27 km, cover South Korea. We obtain ground observations from the Korean Meteorological Administration station network for 93 weather station locations. The results indicate a noticeable improvement in WRF simulations in all station locations. The average of annual index of agreement for surface wind, precipitation, surface pressure, temperature, dewpoint temperature, and relative humidity of all stations is 0.85 (WRF:0.67), 0.62 (WRF:0.56), 0.91 (WRF:0.69), 0.99 (WRF:0.98), 0.98 (WRF:0.98), and 0.92 (WRF:0.87), respectively. While this study focuses on South Korea, the proposed approach can be applied for any measured weather parameters at any location.
View Article and Find Full Text PDF

Download full-text PDF

Source
http://dx.doi.org/10.1109/TNNLS.2021.3100902DOI Listing
August 2021

Quantifying techno-economic indicators' impact on isolated renewable energy systems.

iScience 2021 Jul 12;24(7):102730. Epub 2021 Jun 12.

School of Mechanical Engineering, Shanghai Jiao Tong University, Shanghai 200240, China.

Addressing climate change with the rising global energy usage necessitates electricity sector decarbonization by rapidly moving toward flexible and efficient off-grid renewable energy systems (RESs). This paper analyzes the wind and solar micro-grids, with batteries and pumped hydro storage for a robust off-grid RES techno-economic operation, while considering diverse multi-objective optimization cases. This research has considered the RES variable operational losses in the developed methodology and relations between different indicators are evaluated, revealing a basic understanding between them. The results reveal that the reliability index is inversely related to the oversupply index, while directly related to the system self-sufficiency index. The cost of energy is more sensitive to technical indicators rather than the storage cost and so can be used as a primary monetary index. Energy and cost balance analysis showed that 16%-20% of the used energy was drained in RES operational losses, which were usually ignored in previous studies.
View Article and Find Full Text PDF

Download full-text PDF

Source
http://dx.doi.org/10.1016/j.isci.2021.102730DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC8258682PMC
July 2021
-->