Room-Temperature Synthesis of Covalent Organic Frameworks using Gamma-Irradiation in Open-Air Conditions.

Covalent organic frameworks (COFs), which have layered stacking structures, extended π-conjugation, and periodic frameworks have become a promising class of materials for a wide range of applications. However, their synthetic pathways frequently need high temperatures, enclosed systems under high pressures, an inert atmosphere, and extended reaction time, which restrict their practicality in real-world applications. Herein, the use of gamma irradiation is presented to synthesize highly crystalline COFs at room temperature under an open-air condition within a short time. This is demonstrated that there is no significant difference in crystallinity of COFs by gamma irradiation under air, N2 or Ar atmosphere conditions. Moreover, this approach can successfully fabricate COFs in the vessel with different degrees of transparency or even in a plastic container. Importantly, this strategy is applicable not only to imine linkage of COFs but also effective to the imide linkages of COFs. Most importantly, these COFs demonstrate improved crystallinity, surface area, and thermal stability in comparison to the corresponding materials synthesized via the solvothermal method. Finally, a COF synthesized through gamma irradiation exhibits remarkable photocatalytic activity in promoting the sacrificial hydrogen evolution from water, displaying a more catalytic efficiency compared with that of its solvothermal analogue.

Postoperative pancreatic fistula after pancreaticogastrostomy versus pancreatojejunostomy after pancreatic resection, a comparative systematic review and meta-analysis.

BACKGROUND: In patients undergoing pancreaticoduodenectomy (PD), there has been some evidence favoring pancreaticogastrostomy (PG) over pancreatojejunostomy (PJ) in the occurrence of postoperative pancreatic fistulas (POPF) and considering PG as a safer anastomotic technique. However, other publications revealed comparable incidences of POPF attributed to both techniques. The current work attempts to reach a more consolidated conclusion about such an issue. METHODS: This is a systematic review and meta-analysis that analyzed the studies comparing PG and PJ during PD in terms of the rate of POPF occurrence. Studies were obtained by searching the Scopus, PubMed Central, and Cochrane Central Register of Controlled Trials databases. RESULTS: 35 articles published between 1995 and 2022 presented data from 14,666 patients; 4547 underwent PG and 10,119 underwent PJ. Statistically significant lower rates of POPF (p = 0.044) and clinically relevant CR-POPF (p = 0.043) were shown in the PG group. The post-pancreatectomy hemorrhage (PPH) was significantly higher in the PG group, while no significant difference was found between the two groups in the clinically significant PPH. No statistically significant differences were found regarding the amount of intraoperative blood loss, length of hospital stay, DGE, overall morbidity rates, reoperation rates, or mortality rates. The percentage of male sex in the PG group and the percentage of soft pancreas in the PJ group seem to influence the odds ratio of CR-POPF (p = 0.076 and 0.074, respectively). CONCLUSION: The present study emphasizes the superiority of PG over PJ regarding CR-POPF rates. Higher rates of postoperative hemorrhage were associated with PG. Yet, the clinically significant hemorrhage rate was comparable between the two groups.

Outcomes of revisional surgery options after inadequate sleeve gastrectomy: A comprehensive network meta-analysis.

BACKGROUND: Despite the success of sleeve gastrectomy (SG) in of weight loss and treatment of the medical problems associated with obesity, some concerns have arisen about the need for revisional surgeries after SG in some patients. This study aimed to present an updated and comprehensive comparison among the presently available revisional surgeries employed explicitly in cases of inadequate outcomes after SG, which is the most frequently performed bariatric surgery in contemporary practice. METHODS: This network meta-analysis included studies that compared the outcomes of different revisional bariatric procedures after an inadequate outcome of SG. RESULTS: Searching across the electronic databases yielded 31 eligible articles. Re-SG was associated with the highest rate of significant complications. Patients treated with single anastomosis duodenal-ileal bypass (SADI) had a significantly higher percentage of total weight loss (%TWL) than those treated with one anastomosis gastric bypass (OAGB) and Roux-en-Y gastric bypass (RYGB). The percentage of excess weight loss (%EWL) at the end of the follow-up period was significantly higher in patients in the SADI group compared to those in the RYGB group and the OAGB, and re-SG exhibited the least values compared to SADI, biliopancreatic diversion with duodenal switch (BPD/DS), and OAGB. Significantly lower rates of reflux worsening/de novo development were observed in the SADI group compared to the OAGB group and the re-SG group, which showed significantly higher rates than SADI and RYGB. CONCLUSION: Our comprehensive network meta-analysis highlights SADI as a promising revisional option post-SG, demonstrating superior weight loss outcomes, lower significant complication rates, and a favorable impact on reflux compared to other procedures. While acknowledging the limitations of our study, these findings support the potential efficacy of SADI in addressing the challenges of inadequate weight loss after sleeve gastrectomy.

Erector spinae plane block versus paravertebral block in analgesic outcomes following breast surgery.

This article represents the response to the inquiries adopted by Dr. Raghuraman M Sethuraman, M.D., regarding our recently published study which compared the erector spinae plane block (ESPB) versus paravertebral block (PVB) regarding postoperative analgesic consumption following breast surgeries (Elewa et al, BMC Anesthesiol 22: 1-9, 2022). We would like to introduce our appreciation and gratitude to the author for his interest in our work, despite being inaccurate in some of his comments.

Model systems for regeneration: salamanders.

Salamanders have been hailed as champions of regeneration, exhibiting a remarkable ability to regrow tissues, organs and even whole body parts, e.g. their limbs. As such, salamanders have provided key insights into the mechanisms by which cells, tissues and organs sense and regenerate missing or damaged parts. In this Primer, we cover the evolutionary context in which salamanders emerged. We outline the varieties of mechanisms deployed during salamander regeneration, and discuss how these mechanisms are currently being explored and how they have advanced our understanding of animal regeneration. We also present arguments about why it is important to study closely related species in regeneration research.

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

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.

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

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.

Comparison between erector spinae plane block and paravertebral block regarding postoperative analgesic consumption following breast surgery: a randomized controlled study.

BACKGROUND: Pain control following breast surgery is of utmost importance in order to reduce the chance of chronic pain development, and facilitate early rehabilitation. The erector spinae plane block (ESPB) is a recently developed regional anaesthesia procedure successfully used for different types of surgical procedures including thoracic and abdominal surgeries. METHODS: A double-blind, randomized, controlled trial was conducted on 90 patients who were scheduled for modified radical mastectomy (MRM). Patients were randomly categorized into groups I (women who underwent ESPB), II (women who underwent paravertebral block (PVB), and III (women who underwent general anaesthesia). RESULTS: The ESPB (4.9 ± 1.2 mg) and PVB (5.8 ± 1.3 mg) groups had significantly lower total morphine consumption than the control group had (16.4 ± 3.1 mg; p < 0.001). Notably, patients in the ESPB group had insignificantly lower morphine consumption than those in the PVB group had (p = 0.076). Moreover, patients in the ESPB and PVB groups had a significantly longer time to first required anaesthesia than those in the control group (7.9 ± 1.2 versus 7.5 ± 0.9 versus 2 ± 1.2 h, respectively; p < 0.001). The postoperative visual analog scale scores were lower in the ESPB and PVB groups than in the control group on the first 24 h after the procedure (p < 0.001). CONCLUSION: ESPB and PVB provide effective postoperative analgesia for women undergoing MRM. The ESPB appears to be as effective as the PVB. TRIAL REGISTRATION: The study was registered before the enrolment of the first patient at the Pan African Clinical Trial Registry ( www.pactr.org ) database. Identification number for the registry is (PACTR202008836682092).

Salamander-like tail regeneration in the West African lungfish.

Salamanders, frog tadpoles and diverse lizards have the remarkable ability to regenerate tails. Palaeontological data suggest that this capacity is plesiomorphic, yet when the developmental and genetic architecture of tail regeneration arose is poorly understood. Here, we show morphological and molecular hallmarks of tetrapod tail regeneration in the West African lungfish Protopterus annectens, a living representative of the sister group of tetrapods. As in salamanders, lungfish tail regeneration occurs via the formation of a proliferative blastema and restores original structures, including muscle, skeleton and spinal cord. In contrast with lizards and similar to salamanders and frogs, lungfish regenerate spinal cord neurons and reconstitute dorsoventral patterning of the tail. Similar to salamander and frog tadpoles, Shh is required for lungfish tail regeneration. Through RNA-seq analysis of uninjured and regenerating tail blastema, we show that the genetic programme deployed during lungfish tail regeneration maintains extensive overlap with that of tetrapods, with the upregulation of genes and signalling pathways previously implicated in amphibian and lizard tail regeneration. Furthermore, the lungfish tail blastema showed marked upregulation of genes encoding post-transcriptional RNA processing components and transposon-derived genes. Our results show that the developmental processes and genetic programme of tetrapod tail regeneration were present at least near the base of the sarcopterygian clade and establish the lungfish as a valuable research system for regenerative biology.

Evaluation of Nested Polymerase Chain Reaction and Immunoassay for Rapid Diagnosis of Clostridium difficile in Children with Community Acquired Diarrhea.

BACKGROUND: Clostridium difficile (C. difficile) is a known pathogen associated with diarrhea especially in hospital acquired diarrhea. Yet, it is being recognized as a probable etiology for community acquired diarrhea. The aim of the present study was to detect the presence of C. difficile as a pathogen causing community acquired diarrhea in children and to verify the value of different laboratory methods for diagnosis, namely specific culture, immunoassay for toxin detection, and nested polymerase chain reaction (nested-PCR). METHODS: This prospective study was carried out in children attending Mansoura University Children's hospital complaining of acute diarrhea between the periods from January 2015 until December 2015. Stool samples were collected and subjected to microbiological culture specific for C. difficile and rapid detection of toxin A by chromatographic device and by nested PCR for toxin B detection. RESULTS: Stool samples were collected from 413 children. C. difficile was isolated by culture from 41 patients (9.9%), while direct nested-PCR detected 39 (9.4%) toxigenic strains. Toxin A was detected in all 41 positive culture samples (9.9%). In comparing the clinical and laboratory findings between patients with C. difficile and those without C. difficile, though there was a higher association of bloody, watery diarrhea in patients with C. difficile these associations were not statistically significant (p = 0.4, p = 0.5, respectively). Comparing nested-PCR and toxin detection with culture for detection of C. difficile showed an excellent accuracy of both methods. CONCLUSIONS: From this study, we can conclude that community acquired diarrhea due to C. difficile is common among children. It should be sought among the pathogens causing this infection. Rapid laboratory detection of toxin A by a rapid chromatography device is accurate compared to time consuming culture. Moreover, nested PCR for toxin B is an accurate and rapid method when it is available.

Efficacy and Safety of Infliximab Versus Adalimumab in Adult Subjects With Moderate to Severe Ulcerative Colitis: A Systematic Review and Meta-Analysis.

Ulcerative colitis (UC) is an inflammatory disorder affecting the colon, and typically, during the disease course, the condition may exacerbate, relapse, and remit. One of the most successful lines for inducing and maintaining clinical remission in subjects with UC is biological therapy with anti-tumor necrosis factor α (anti-TNF) agents, including adalimumab (ADA) and infliximab (IFX). This meta-analysis is an attempt to obtain complementary information driven by real-world experience (RWE) concerning the efficacy and safety of two of the most popular anti-TNFs in treating UC. This is a systematic review and meta-analysis of RWE studies comparing ADA and IFX as naïve anti-TNF agents for the treatment of subjects with UC. Studies were obtained by searching Scopus, Google Scholar, the Cochrane Central Register of Controlled Trials, Embase, and the PubMed Central databases. Patients treated with IFX showed significantly higher induction responses. No statistically significant difference was found in the comparison of response in the maintenance treatment period. Higher overall adverse events were related to IFX treatment, with serious adverse events that were nonsignificantly higher in the ADA-treated group. In conclusion, IFX demonstrated significantly higher induction responses compared to ADA in patients with moderate-to-severe UC. IFX was associated with higher overall adverse events, whereas serious adverse events were non-significantly higher in the ADA-treated group. IFX may be favored as a first-line agent for its induction efficacy, and the choice between IFX and ADA should be individualized based on comprehensive clinical evaluation.

Effective remediation of Pb2+ polluted environment by adsorption onto recyclable hydroxyl bearing covalent organic framework.

The removal of heavy metal ions from wastewater has attracted considerable interest because of their toxicity. Adsorption is one of the most promising methods for the removal of heavy metal ions due to its simplicity and effectiveness. Recently, covalent organic frameworks (COFs) have become promising adsorbents for effective wastewater remediation. However, many building blocks have been developed, and the design of COFs with high adsorption efficiency remains a challenge. Here, a covalent organic framework (DHTP-TPB COF) decorated with hydroxyl groups was developed for the efficient removal of Pb2+ ions. The DHTP-TPB COF showed excellent performance in adsorbing Pb2+ from aqueous solution. More importantly, DHTP-TPB COF exhibited high selectivity for Pb2+ compared to other competing ions, capturing Pb2+ ions with a removal efficiency of over 96% at pH 4. The results show that the DHTP-TPB COF exhibits excellent adsorption capacity at pH 4 of up to 154.3 mg/g for Pb2+ ions; the value is comparable to many previously reported COFs. Moreover, the adsorbed Pb2+ ions could be easily eluted with a 0.1 M EDTA solution, and the DHTP-TPB COF can be reused for more than five adsorption-desorption cycles without significant loss of adsorption capacity. Moreover, the adsorption mechanism was revealed using XPS analysis, indicating the formation of strong coordination-bonding interactions between hydroxyl and Pb2+ ions. Therefore, the DHTP-TPB COF prepared herein has high potential for the treatment of Pb2+-contaminated wastewater and is promising for the adsorption of Pb2+ ions in practical applications.

A small noncoding RNA links ribosome recovery and translation control to dedifferentiation during salamander limb regeneration.

Building a blastema from the stump is a key step of salamander limb regeneration. Stump-derived cells temporarily suspend their identity as they contribute to the blastema by a process generally referred to as dedifferentiation. Here, we provide evidence for a mechanism that involves an active inhibition of protein synthesis during blastema formation and growth. Relieving this inhibition results in a higher number of cycling cells and enhances the pace of limb regeneration. By small RNA profiling and fate mapping of skeletal muscle progeny as a cellular model for dedifferentiation, we find that the downregulation of miR-10b-5p is critical for rebooting the translation machinery. miR-10b-5p targets ribosomal mRNAs, and its artificial upregulation causes decreased blastema cell proliferation, reduction in transcripts that encode ribosomal subunits, diminished nascent protein synthesis, and retardation of limb regeneration. Taken together, our data identify a link between miRNA regulation, ribosome biogenesis, and protein synthesis during newt limb regeneration.

One Anastomosis Gastric Bypass (OAGB) with a 150-cm Biliopancreatic Limb (BPL) Versus a 200-cm BPL, a Systematic Review and Meta-analysis.

This is a systematic review and meta-analysis that assessed the impact of performing OAGB with a 150-cm BPL versus a 200-cm BPL concerning weight loss, comorbidities remission, and adverse nutritional effects. The analysis included studies that compared patients who underwent OAGB with a 150-cm BPL and 200-cm BPL. Eight studies were eligible for this review after searching in the EMBASE, PubMed central database, and Google scholar. The pooled analysis revealed favoring the 200-cm BPL limb length for weight loss, with a highly significant difference in the TWL% (p=0.009). Both groups showed comparable comorbidities remission. Significantly higher ferritin and folate deficiency rates were found in the 200-cm BPL group. Considering a 200-cm BPL when performing OAGB delivers a better weight loss outcome than a 150-cm BPL, which is at the expense of a more severe nutritional deficiency. No significant differences were found regarding the comorbidities' remission.

Nissen Versus Toupet Fundoplication For Gastro-oesophageal Reflux Disease, Short And Long-term Outcomes. A Systematic Review And Meta-analysis.

BACKGROUND: Gastroesophageal reflux disease (GERD) remains one of the most commonly encountered gastrointestinal disorders. Proton pump inhibitors still show an inadequate effect on about 10% to 40% of the patients. Laparoscopic antireflux surgery is the surgical alternative for managing GERD in patients who are not responding to proton pump inhibitors. AIM OF THE STUDY: This study objected at comparing laparoscopic Nissen fundoplication and laparoscopic Toupet fundoplication (LTF) concerning the short-term and long-term outcomes. PATIENTS AND METHODS: This is a systematic review and meta-analysis that evaluated the studies comparing between Nissen fundoplication and LTF for the treatment of GERD. Studies were obtained by searching on the EMBASE, the Cochrane Central Register of Controlled Trials, and PubMed central database. RESULTS: The LTF group showed significantly longer operation time, less postoperative dysphagia and gas bloating, less pressure on the lower esophageal sphincter, and higher Demeester scores. No statistically significant differences were found between the 2 groups in the perioperative complications, the recurrence of GERD, the reoperation rate, the quality of life, or the reoperation rate. CONCLUSION: LTF is favored for the surgical treatment of GERD being of lower postoperative dysphagia and gas bloating rates. These benefits were not at the expense of significantly additional perioperative complications or surgery failure.

Three-Dimensional Multi-detector Computed Tomography (3D-MDCT) Gastric Volumetry in Patients with obesity and Normal-Weight Individuals.

BACKGROUND: Obesity is a widely prevalent medical and socioeconomic problem. Bariatric surgery is indicated for patients with clinically severe obesity. Reduction of gastric volume is an important factor that contributes to weight loss after laparscopic sleeve gastrectomy (LSG). The impact of the gastric volume on weight after LSG has been studied. AIM OF THE STUDY: This study was designed to assess the gastric volume in patients with obesity prior to LSG and in the normal-weight patients, using three-dimensional multi-detector computer tomography (3D-MDCT), and to evaluate the potential correlation of the gastric volume with body mass index (BMI). PATIENTS AND METHODS: A total of 100 patients were equally enrolled in two groups: one group for patients with obesity scheduled for LSG and another one for normal-weight patients scheduled for non-bariatric surgery. The study patients underwent 3D-MDCT gastric volumetry. RESULTS: The gastric volume ranged from 525 to 1170 mL in patients with obesity and from 312 to 676 mL in the normal-weight group. Statistically significant difference was found between the two groups. Age, weight, and BMI were found to be predictors for the gastric volume in normal-weight patients only. CONCLUSION: MDCT gastric volumetry is a feasible method to assess the stomach volume. Higher volumes were evident in patients with obesity. Age, weight, and BMI are predictors for the gastric volume in normal-weight patients with linear regression equations that could help during the preoperative planning of bariatric surgeries.

Surgical Management of Perforated Peptic Ulcer: A Comparative Meta-analysis of Laparoscopic Versus Open Surgery.

BACKGROUND: Despite the widescale success of proton pump inhibitors to reducing the incidence of peptic ulcer disease, perforated peptic ulcer (PPU) remains a significant cause of severe complications and death. The implementation of open or surgical repair of PPU should be guided by reliable guidelines which are based on current systematic evidence. OBJECTIVES: To assess the comparative efficacy and safety of laparoscopic and open repair of PPU. METHODS: A systematic review and meta-analysis was conducted based on retrospective, prospective cohort studies, and randomized clinical trials. Duration of surgery and postoperative complications and death were collected from eligible studies, and the outcomes were pooled using mean differences (MD) or relative risks (RRs) for numerical and binary outcomes, respectively. The estimated variance was expressed as 95% confidence intervals (95% CIs). RESULTS: Forty-five studies were included (8456 patients, 56.08% underwent open repair, 6 prospective studies, 7 randomized clinical trials, and 32 retrospective studies). Compared with open repair, laparoscopic surgeries were associated with longer operative times (MD=8.36, 95% CI, 0.49-16.22), shorter hospital stay (MD=-2.74, 95% CI, -3.70 to-1.79), a higher risk of suture leakage (RR=1.91, 95% CI, 1.04-3.49) and lower risks of mortality (RR=0.57, 95% CI, 0.47-0.70), septic shock (RR=0.69, 95% CI, 0.49-0.98), renal failure (RR=0.38, 95% CI, 0.18-0.79), and wound infection (RR=0.26, 95% CI, 0.19-0.37). CONCLUSION: Laparoscopic repair of PPU showed promising safety outcomes; however, future well-designed randomized studies are warranted to reduce the observed performance bias and possible selection bias in individual studies.

Epicardium-derived cells organize through tight junctions to replenish cardiac muscle in salamanders.

The contribution of the epicardium, the outermost layer of the heart, to cardiac regeneration has remained controversial due to a lack of suitable analytical tools. By combining genetic marker-independent lineage-tracing strategies with transcriptional profiling and loss-of-function methods, we report here that the epicardium of the highly regenerative salamander species Pleurodeles waltl has an intrinsic capacity to differentiate into cardiomyocytes. Following cryoinjury, CLDN6+ epicardium-derived cells appear at the lesion site, organize into honeycomb-like structures connected via focal tight junctions and undergo transcriptional reprogramming that results in concomitant differentiation into de novo cardiomyocytes. Ablation of CLDN6+ differentiation intermediates as well as disruption of their tight junctions impairs cardiac regeneration. Salamanders constitute the evolutionarily closest species to mammals with an extensive ability to regenerate heart muscle and our results highlight the epicardium and tight junctions as key targets in efforts to promote cardiac regeneration.

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

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.