Online monitoring of protein refolding in inclusion body processing using intrinsic fluorescence

Inclusion bodies (IBs) are protein aggregates formed as a result of overexpression of recombinant protein in E. coli. The formation of IBs is a valuable strategy of recombinant protein production despite the need for additional processing steps, i.e., isolation, solubilization and refolding. Industrial process development of protein refolding is a labor-intensive task based largely on empirical approaches rather than knowledge-driven strategies. A prerequisite for knowledge-driven process development is a reliable monitoring strategy. This work explores the potential of intrinsic tryptophan and tyrosine fluorescence for real-time and in situ monitoring of protein refolding. In contrast to commonly established process analytical technology (PAT), this technique showed high sensitivity with reproducible measurements for protein concentrations down to 0.01 g L- 1 . The change of protein conformation during refolding is reflected as a shift in the position of the maxima of the tryptophan and tyrosine fluorescence spectra as well as change in the signal intensity. The shift in the peak position, expressed as average emission wavelength of a spectrum, was correlated to the amount of folding intermediates whereas the intensity integral correlates to the extent of aggregation. These correlations were implemented as an observation function into a mechanistic model. The versatility and transferability of the technique were demonstrated on the refolding of three different proteins with varying structural complexity. The technique was also successfully applied to detect the effect of additives and process mode on the refolding process efficiency. Thus, the methodology presented poses a generic and reliable PAT tool enabling real-time process monitoring of protein refolding.

Advances in clinical applications of bioceramics in the new regenerative medicine era

In this editorial, we comment on the hard and soft tissue applications of different ceramic-based scaffolds prepared by different mechanisms such as 3D printing, sol-gel, and electrospinning. The new concept of regenerative medicine relies on biomaterials that can trigger in situ tissue regeneration and stem cell recruitment at the defect site. A large percentage of these biomaterials is ceramic-based as they provide the essential requirements of biomaterial principles such as tailored multisize porosity, antibacterial properties, and angiogenic properties. All these previously mentioned properties put bioceramics on top of the hierarchy of biomaterials utilized to stimulate tissue regeneration in soft and hard tissue wounds. Multiple clinical applications registered the use of these materials in triggering soft tissue regeneration in healthy and diabetic patients such as bioactive glass nanofibers. The results were promising and opened new frontiers for utilizing these materials on a larger scale. The same results were mentioned when using different forms and formulas of bioceramics in hard defect regeneration. Some bioceramics were used in combination with other polymers and biological scaffolds to improve their regenerative and mechanical properties. All this progress will enable a larger scale of patients to receive such services with ease and decrease the financial burden on the government.

Outcomes after surgery for children in Africa (ASOS-Paeds): a 14-day prospective observational cohort study

BACKGROUND

Safe anaesthesia and surgery are a public health imperative. There are few data describing outcomes for children undergoing anaesthesia and surgery in Africa. We aimed to get robust epidemiological data to describe patient care and outcomes for children undergoing anaesthesia and surgery in hospitals in Africa.

METHODS

This study was a 14-day, international, prospective, observational cohort study of children (aged <18 years) undergoing surgery in Africa. We recruited as many hospitals as possible across all levels of care (first, second, and third) providing surgical treatment. Each hospital recruited all eligible children for a 14-day period commencing on the date chosen by each participating hospital within the study recruitment period from Jan 15 to Dec 23, 2022. Data were collected prospectively for consecutive patients on paper case record forms. The primary outcome was in-hospital postoperative complications within 30 days of surgery and the secondary outcome was in-hospital mortality within 30 days after surgery. We also collected hospital-level data describing equipment, facilities, and protocols available. This study is registered with ClinicalTrials.gov, NCT05061407.

FINDINGS

We recruited 8625 children from 249 hospitals in 31 African countries. The mean age was 6·1 (SD 4·9) years, with 5675 (66·0%) of 8600 children being male. Most children (6110 [71·2%] of 8579 patients) were from category 1 of the American Society of Anesthesiologists Physical Status score undergoing elective surgery (5325 [61·9%] of 8604 patients). Postoperative complications occurred in 1532 (18·0%) of 8515 children, predominated by infections (971 [11·4%] of 8538 children). Deaths occurred in 199 (2·3%) of 8596 patients, 169 (84·9%) of 199 patients following emergency surgeries. Deaths following postoperative complications occurred in 166 (10·8%) of 1530 complications. Operating rooms were reported as safe for anaesthesia and surgery for neonates (121 [54·3%] of 223 hospitals), infants (147 [65·9%] of 223 hospitals), and children younger than 6 years (188 [84·3%] of 223 hospitals).

INTERPRETATION

Outcomes following anaesthesia and surgery for children in Africa are poor, with complication rates up to four-fold higher (18% vs 4·4-14%) and mortality rates 11-fold higher than high-income countries in a crude, unadjusted comparison (23·15 deaths vs 2·18 deaths per 1000 children). To improve surgical outcomes for children in Africa, we need health system strengthening, provision of safe environments for anaesthesia and surgery, and strategies to address the high rate of failure to rescue.

FUNDING

Jan Pretorius Research Fund of the South African Society of Anaesthesiologists and Association of Anesthesiologists of Uganda.

Corrigendum: State-of-the-art and novel approaches to mild solubilization of inclusion bodies

[This corrects the article DOI: 10.3389/fbioe.2023.1249196.].

State-of-the-art and novel approaches to mild solubilization of inclusion bodies

Throughout the twenty-first century, the view on inclusion bodies (IBs) has shifted from undesired by-products towards a targeted production strategy for recombinant proteins. Inclusion bodies can easily be separated from the crude extract after cell lysis and contain the product in high purity. However, additional solubilization and refolding steps are required in the processing of IBs to recover the native protein. These unit operations remain a highly empirical field of research in which processes are developed on a case-by-case basis using elaborate screening strategies. It has been shown that a reduction in denaturant concentration during protein solubilization can increase the subsequent refolding yield due to the preservation of correctly folded protein structures. Therefore, many novel solubilization techniques have been developed in the pursuit of mild solubilization conditions that avoid total protein denaturation. In this respect, ionic liquids have been investigated as promising agents, being able to solubilize amyloid-like aggregates and stabilize correctly folded protein structures at the same time. This review briefly summarizes the state-of-the-art of mild solubilization of IBs and highlights some challenges that prevent these novel techniques from being yet adopted in industry. We suggest mechanistic models based on the thermodynamics of protein unfolding with the aid of molecular dynamics simulations as a possible approach to solve these challenges in the future.

Ultrasound-guided lumbar erector spinae plane block versus caudal block for postoperative analgesia in pediatric hip and proximal femur surgery: a randomized controlled study

BACKGROUND

According to previous research, 20% of infants experience prolonged postsurgical pain 6-12 months after major surgery, which is linked to functional impairment and a lower quality of life. The aim of our study is to evaluate whether the analgesic effect of the erector spinae plane block (ESPB) is superior to that of caudal epidural anesthesia (CEA) in pediatric patients undergoing hip or proximal femoral surgeries.

METHODS

Seventy-six children ranging in age from 1 to 7 years scheduled for hip or proximal femur surgery were randomly assigned to receive either a unilateral ultrasound-guided ESPB or CEA with bupivacaine 0.25% at a dose of 0.5 ml/kg. The primary outcome was the Face, Legs, Activity, Cry, and Consolability (FLACC) scale 2 h postoperatively. The secondary outcomes were pain scores every 15 min for the first hour and then at 6, 12, and 24 h postoperatively; the block failure rate; time to perform a successful block; and time to first rescue analgesia.

RESULTS

The FLACC score 2 h post¬operatively was not superior in the ESPB group compared to the CEA group; indeed, it was significantly higher in the ESPB group at 15 and 30 min post-operation (P = 0.005, 0.004, respectively). Additionally, the time to first rescue analgesia was prolonged in the CEA group (P < 0.001). The time to perform a successful block was comparable between the groups.

CONCLUSIONS

The analgesic effect of the ESPB was not superior to that of CEA in pediatric patients undergoing hip and proximal femur surgery.

Success of embryo transfer of hybrid embryos in Old World camelids: A first study

This is the first study to test the embryo transfer (ET) of hybrid embryos in Old World camelids and produces a live calf from a dromedary recipient. Hybrid embryos were collected from 7 dromedary and 10 Bactrian donors, with or without ovarian super-stimulation, and transferred to dromedary recipients. Pregnancy diagnosis was conducted on Day 10 post-ET by using the progesterone-ELISA test and trans-rectal ultrasonography at 1 and 2 months of gestation. The date of abortion, stillbirth, or normal calving for each pregnant recipient was recorded. Without ovarian super-stimulation, two and one recipients were pregnant at 10 days post-ET, from ♂ Bactrian X ♀ dromedary and ♂ dromedary X ♀ Bactrian, respectively. While at 2 months of gestation, only 1 recipient was diagnosed pregnant from ♂ Bactrian X ♀ dromedary. Response to ovarian super-stimulation was successful in all 4 of the tested dromedary donors and in 8 out of 10 Bactrian donors. Additionally, 4 super-stimulated Bactrian donors (40%) showed failure of ovulation. The number of super-stimulated developed follicles and recovered embryos was higher in dromedary donors compared to Bactrian donors. Ten and two recipients were diagnosed pregnant at 10 days post-ET for ♂ Bactrian X ♀ dromedary and ♂ dromedary X ♀ Bactrian, respectively. At 2 months of gestation, the number of pregnant recipients from ♂ Bactrian X♀ dromedary was reduced to 8, while the two pregnant recipients from ♂ dromedary X♀ Bactrian remained pregnant. Total early pregnancy loss (EPL) at 2 months gestation for all transferred hybrid embryos, obtained with or without ovarian super-stimulation, was 4/15 (26.6%). One healthy male calf was born from a recipient, with a total gestation period of 383 days, that received an embryo from a Bactrian male and a dromedary donor. Stillbirth was observed in six cases after 10.5-12 months of gestation and 3 cases aborted between 7-9 months of gestation due to Trypanosomiasis. In conclusion, embryo transfer of hybrid embryos in Old World camelids is successful. However, further studies are required to improve the outcome of this technology to be used for meat and milk production in camels.

A single center comparative study of two single use digital flexible ureteroscopy in the management of renal stones less than 2 cm

PURPOSE

For renal stones < 2 cm, guidelines recommend the use of retrograde intrarenal surgery as a first line treatment option. Many available single use flexible ureteroscopy were found. We aim to compare the effectiveness of two single use flexible ureteroscopy; Pusen Uscope 3011 versus LithoVue in the management of renal stones less than 2 cm.

METHODS

Our study prospectively included 60 patients equally divided in to two groups: Pusen group and LithoVue group during the period from June 2020 to June 2021. The included patients were above 18 years old. Perioperative details as operative time, fluoroscopy time, hospital stay, and complications were recorded. Stone free rate was assessed. Base purchase cost was also compared.

RESULTS

There was no statistically significant difference between the two groups regarding age, gender, and body mass index (BMI), stones size, side, number and location. The perioperative evaluation and outcome had no statistically significant differences between the two groups regarding the operative time, hospital stay, access sheath use, and stone free rate or radiation exposure. Among all cases, we had 49 cases (81.6%) with no postoperative complications (21 cases for Pusen group and 28 cases for LithoVue group). The incidence of postoperative complications was significantly higher among Pusen group than LithoVue group (p = 0.02). Initial purchase cost for both FURS had no significant difference (P = 0.86).

CONCLUSION

RIRS can be performed effectively with Pusen 3011 and LithoVue single use flexible ureteroscopy in patients diagnosed with renal calculi < 2 cm with superior outcomes with LithoVue.

Feasibility and efficacy of erector spinae plane block versus transversus abdominis plane block in laparoscopic bariatric surgery: a randomized comparative trial

BACKGROUND

Overweight and obesity are growing public health concerns worldwide. Bariatric surgery is a modality of weight reduction; however, postoperative pain can increase the length of hospital stay, with all the associated consequences. While regional anesthesia is an available option, the feasibility of performing abdominal wall blocks on patients with obesity is questionable.

METHODS

Sixty adult patients with a body mass index of 40-50 kg/m2 undergoing laparoscopic bariatric surgery were randomly assigned to receive either an ultrasound-guided transversus abdominis plane (TAP) or erector spinae plane (ESP) block. The primary outcome was the analgesic effect in the first 24 h postoperatively, assessed using the mean visual analog scale (VAS) score. Secondary outcomes were the time required for a successful block, incidence of complications, time to first rescue analgesia, time to flatus or stool passage, and total opioid consumption.

RESULTS

The mean VAS score during the first 24 h was higher with the TAP block than with the ESP block (2.78 ± 0.34 vs. 2.32 ± 0.12, P < 0.001). Additionally, the time to first rescue analgesia was greater with the ESP block (P = 0.001) and the time required for a successful block was higher with the TAP block (P = 0.001). However, the incidence of complications, total opioid consumption, and other secondary outcomes was similar between the groups.

CONCLUSIONS

Compared with the TAP block, the bilateral ESP block is a more feasible and effective method for intra- and postoperative analgesia in patients undergoing laparoscopic bariatric surgery.

ADDITION OF LOCAL CRYOTHERAPY FOR TREATMENT OF POST-MASTECTOMY LYMPHEDEMA

Worldwide, lymphedema can present as a significant health issue. Left untreated, it can have long-term medical and psychological consequences for patients. Cryotherapy is a new physical therapy modality used for many purposes including reduction of pain, inflammation, and edema. It is thought to decrease interstitial fluid volume through many mechanisms. Therefore, it is reasonable to think that cryotherapy might have a positive effect in treatment of lymphedema. The goal of this study was to investigate how local cryotherapy in combination with standard therapy affects patient outcomes. Forty post-mastectomy female patients aged 40-60 years old with lymphedema were referred to the outpatient clinics of the Faculty of Physical Therapy at South Valley University for medical treatment and follow-up by the vascular surgery department. Patients were randomly divided into two groups of equal size. Traditional physical therapy programs (manual lymphatic drainage, pneumatic compression, bandaging, breathing exercises, circulatory exercises, shoulder mobilizations, and ROM exercises) were combined with pulsed local cryotherapy three times per week for 12 weeks in Group (A). For 12 weeks, Group (B) received only traditional physical therapy three times per week. Patients were evaluated using circumferential measurement with tape at the wrist, below the elbow, and above the elbow level, as well as ultrasonography to assess skin thickness before the start of physical therapy, 6 weeks later, and at the end of the treatment (after 12 weeks). Results indicate that cryotherapy is an effective adjunct modality for the treatment of secondary lymphedema and should be added to physical therapy protocols for lymphedema rehabilitation.

Unraveling Synergistic Redox Interactions in Tetraphenylporphyrin-Polyluminol-Carbon Nanotube Composite for Capacitive Charge Storage

Organic redox-active materials, combined with high-surface-area carbonaceous substrates, form sustainable and low-cost composites with greatly enhanced electrochemical charge storage capacities. The electrochemical capacitive behavior of a composite electrode containing tetraphenylporphyrin sulfonate (TPPS), Chemically polymerized luminol (CpLum), and carbon nanotubes (TPPS-CpLum-CNT) was studied and compared with individual TPPS-CNT and CpLum-CNT composites. The dual-layer TPPS-CpLum had a combined contribution to the electrochemical charge storage, which led to an increased volumetric capacitance over the bare CNT and individual TPPS-CNT and CpLum-CNT composites. The synergistic interactions in the composite enabled faster charge storage kinetics and great stability. Spectroscopic analyses revealed that TPPS and CpLum interact electronically through noncovalent π-π and van der Waals bonds, which facilitates the transfer of electrons during charge and discharge. The synergy in charge storage was confirmed by density functional theory computational analysis, which suggested favorable physisorption and interfacial electronic interactions for TPPS adsorbed to a CpLum-carbon substrate. The combined insights from experimental and computational characterizations show that superimposing redox-active organic layers can be an effective and sustainable approach to design and engineer the surface of carbonaceous materials for capacitive charge storage.

Caring for carers: A virtual psychosocial supervision intervention to improve the quality and sustainability of mental health and psychosocial support in humanitarian contexts

Introduction

Mental health and psychosocial support (MHPSS) staff in humanitarian settings have limited access to clinical supervision and are at high risk of experiencing burnout. We previously piloted an online, peer-supervision program for MHPSS professionals working with displaced Rohingya (Bangladesh) and Syrian (Turkey and Northwest Syria) communities. Pilot evaluations demonstrated that online, peer-supervision is feasible, low-cost, and acceptable to MHPSS practitioners in humanitarian settings.

Objectives

This project will determine the impact of online supervision on i) the wellbeing and burnout levels of local MHPSS practitioners, and ii) practitioner technical skills to improve beneficiary perceived service satisfaction, acceptability, and appropriateness.

Methods

MHPSS practitioners in two contexts (Bangladesh and Turkey/Northwest Syria) will participate in 90-minute group-based online supervision, fortnightly for six months. Sessions will be run on zoom and will be co-facilitated by MHPSS practitioners and in-country research assistants. A quasi-experimental multiple-baseline design will enable a quantitative comparison of practitioner and beneficiary outcomes between control periods (12-months) and the intervention. Outcomes to be assessed include the Kessler-6, Harvard Trauma Questionnaire and Copenhagen Burnout Inventory and Client Satisfaction Questionnaire-8.

Results

A total of 80 MHPSS practitioners will complete 24 monthly online assessments from May 2022. Concurrently, 1920 people receiving MHPSS services will be randomly selected for post-session interviews (24 per practitioner).

Conclusions

This study will determine the impact of an online, peer-supervision program for MHPSS practitioners in humanitarian settings. Results from the baseline assessments, pilot evaluation, and theory of change model will be presented.

Disclosure

No significant relationships.

Video Laryngoscope versus USB borescope aided endotracheal intubation in adults with anticipated difficult airway: a prospective randomized controlled study

Background

Video laryngoscopes are approved equipment for difficult airway intubations. The borescope, which was introduced during the coronavirus disease 2019 (COVID-19) era, is placed over a direct laryngoscope blade to provide an economical video laryngoscope. In the current study, we investigated the use of an endotracheal tube mounted over a USB borescope versus a video laryngoscope in patients with suspected difficult airways.

Methods

After obtaining informed consent, 120 adult patients with suspected difficult airways undergoing elective surgery were included in this study. Patients were randomized into the USB borescope and video laryngoscope groups. The primary outcome was time to successful intubation. The secondary outcomes included hemodynamic changes, anesthetist’s satisfaction, and the incidence of complications.

Results

Intubation time was comparable between the two groups (video laryngoscope: 30.63 s and borescope: 28.35 s; P = 0.166). However, the view was clearer (P = 0.026) and the incidence of fogging was lower (P = 0.015) with the video laryngoscope compared to the borescope. Conversely, anesthetist’s satisfaction frequency was higher with the borescope than with the video laryngoscope (P < 0.001).

Conclusions

The video laryngoscope provided a better view and less fogging with an intubation time that was comparable to that of the borescope; however, the higher cost of the video laryngoscope limits its availability. Therefore, the borescope is a low-cost, readily available device that can be used for intubating patients with potentially difficult airways.

Addition of local cryotherapy for treatment of post-mastectomy lymphedema

Worldwide, lymphedema can present as a significant health issue. Left untreated, it can have long-term medical and psychological consequences for patients. Cryotherapy is a new physical therapy modality used for many purposes including reduction of pain, inflammation, and edema. It is thought to decrease interstitial fluid volume through many mechanisms. Therefore, it is reasonable to think that cryotherapy might have a positive effect in treatment of lymphedema. The goal of this study was to investigate how local cryotherapy in combination with standard therapy affects patient outcomes. Forty post-mastectomy female patients aged 40-60 years old with lymphedema were referred to the outpatient clinics of the Faculty of Physical Therapy at South Valley University for medical treatment and follow-up by the vascular surgery department. Patients were randomly divided into two groups of equal size. Traditional physical therapy programs (manual lymphatic drainage, pneumatic compression, bandaging, breathing exercises, circulatory exercises, shoulder mobilizations, and ROM exercises) were combined with pulsed local cryotherapy three times per week for 12 weeks in Group (A). For 12 weeks, Group (B) received only traditional physical therapy three times per week. Patients were evaluated using circumferential measurement with tape at the wrist, below the elbow, and above the elbow level, as well as ultrasonography to assess skin thickness before the start of physical therapy, 6 weeks later, and at the end of the treatment (after 12 weeks). Results indicate that cryotherapy is an effective adjunct modality for the treatment of secondary lymphedema and should be added to physical therapy protocols for lymphedema rehabilitation.

A prospective, randomized comparison of standard prone position versus flank-free modified supine position in percutaneous nephrolithotomy: A single-center initial experience

Background:

Percutaneous nephrolithotomy (PCNL) is the first choice for treatment of large renal stone >2 cm. The prone position is the classical position preferred by most surgeons. Aiming to improve patient anesthesia and surgery-related inconveniences of the prone position, Valdivia et al., 1987, described the performance of PCNL with the patient in the supine position. Hence, we aimed to study the safety and efficacy of flank-free modified supine position in PCNL compared to the standard prone position.

Patients and Methods:

This is a prospective randomized study for 60 patients with large renal stones planned for PCNL operation during the period from November 2017 to May 2019. Patients were divided into two groups (30 patients each group): Group A – patients underwent PCNL in the prone position and Group B – patients underwent PCNL in the modified flank supine position. Patients’ demographics, stone size, Hounsfield unit with intraoperative details as fluoroscopy time, operative time, and complications were recorded. Postoperatively, need for or not to blood transfusions, hospital stay, stone-free status, and postoperative complications were assessed.

Results:

There was no statistically significant difference between the prone and supine positions regarding stone size (4 cm vs. 4.5 cm, P = 0.16), Hounsfield unit (940 HU vs. 955 HU, P = 0.78), body mass index (31.2 kg/m² vs. 32.5 kg/m², P = 0.49), fluoroscopy time (6.9 min vs. 7.3 min, P = 0.5), operative time (89.5 min vs. 90.4 min, P = 0.9), residual stones (10% vs. 20%, P = 0.8), and hospital stay (45.6 h vs. 48.6 h, P = 0.5). Fever occurred in 3.3% of cases in each group and urine leakage observed in one patient with prone position. No blood transfusion was needed in both the groups.

Conclusions:

PCNL in the modified supine position proved to be a safe and effective choice compared to the prone position for adult patients with large renal calculi.

Evaluation of a novel technique of bladder neck and supramontanal sparing ejaculatory preserving transurethral prostatectomy

PURPOSE

Transurethral resection of the prostate (TURP) can achieve highly satisfying symptomatic and functional outcomes but the loss of antegrade ejaculation represents a major reason for the avoidance of surgical treatment to preserve normal ejaculation and paternity. We present a novel technique to duplicate both bladder neck sparing and supramontanal sparing with resection of apical tissues to improve voiding and antegrade ejaculation.

METHODS

A prospective study done from June 2018 to June 2020 on 60 consecutive male patients with normal sexual activity diagnosed with benign prostatic enlargement. These patients were randomized into two groups; 30 patients in each group. Group 1 underwent bladder neck and supramontanal sparing ejaculatory preserving transurethral bipolar resection of prostate (ep-TUBRP) and Group 2 underwent classic transurethral bipolar resection of prostate (c-TUBRP). All patients were evaluated pre- and postoperatively (after 3 months) using IPSS, Qmax and by IIEF-5.

RESULTS

In both groups, there were significant improvements 3 months postoperative in Qmax [7.97 mL/s to 18.47 mL/s (group A) and 7.8 to 20.7 mL/s (group B)] and in micturition symptoms according to reductions in IPSS score [24 to 7.5 (group A) and 25 to 8.5 (group B)]. IIEF-5 score improved significantly from a mean of 12.9 to 18.6 (group A) and from 11.6 to 16.4 (group B). Antegrade ejaculation reported in 80% of patients in group A and 27% in group B which was significant (p < 0.001). Postoperative period did not reveal acute urinary retention, stress urinary incontinence, or serious adverse events.

CONCLUSIONS

On short-term results, bladder neck and supramontanal ejaculation preserving transurethral bipolar resection of the prostate is superior to classic TURP in preservation of forward ejaculation with comparable efficacy in micturition parameters.

The use of intraoperative bedside lung ultrasound in optimizing positive end expiratory pressure in obese patients undergoing laparoscopic bariatric surgeries

BACKGROUND

Anesthetic management of patients with obesity undergoing laparoscopic abdominal surgeries requires careful plan for intraoperative mechanical ventilation aiming to avoid lung atelectasis and/or overdistention. There are conflicting data on the optimum positive end expiratory pressure (PEEP) during these surgeries. We hypothesized that lung ultrasound could be used for PEEP titration during laparoscopic surgery.

OBJECTIVE

The purpose of this study is to evaluate the effectiveness of intraoperative individualized lung ultrasound-guided PEEP in obese patients undergoing laparoscopic bariatric surgery on intraoperative partial arterial oxygen tension (PaO₂) and early postoperative pulmonary complications.

METHODS

A randomized controlled trial included 40 adult patients with body mass index (BMI) > 35 kg/m² undergoing laparoscopic bariatric surgery. Patients were randomized into: control group (n = 20) who received PEEP 4 cm.H₂ O and ultrasound-guided group (n = 20) who received individualized lung ultrasound stepwise PEEP. All patients received volume-controlled ventilation with a tidal volume of 6 mL/kg of ideal weight and a fraction of inspired oxygen of .5. The primary outcome was the difference in partial arterial oxygen tension (PaO₂) between the control group and the ultrasound-guided group. The secondary outcomes included the incidence of early postoperative pulmonary atelectasis, respiratory failure, bronchospasm, hypoxia or pneumothorax.

SETTINGS

General surgery operating theatre at Cairo University hospitals.

RESULTS

Ultrasound-guided group showed higher PO₂ after PEEP optimization and postoperatively compared with control group (P = .005, and P = .01 respectively). Also, ultrasound-guided group showed no postoperative complications compared with control group that had 5 cases who developed postoperative pulmonary complications in the form of hypoxia and basal collapse in the first 24 hour postoperatively chest x ray (0% versus 25%, P = .047).

CONCLUSION

In patients with obesity undergoing laparoscopic bariatric surgery, the use of lung ultrasound individualized stepwise PEEP approach improved oxygenation, compliance and reduced the incidence of postoperative pulmonary atelectasis and hypoxia without causing hemodynamic instability.

Impact of risk-factor modification on arrhythmia recurrence among morbidly obese patients undergoing atrial fibrillation ablation

BACKGROUND

Morbid obesity is associated with prohibitively high arrhythmia recurrence rates following atrial fibrillation (AF) ablation.

DESIGN

This was a single-center study comprising 239 patients with morbid obesity and symptomatic paroxysmal or persistent AF undergoing AF ablation compared to 239 patients with a body mass index less than 30 kg/m² matched based on age, sex, ejection fraction, AF type, presence and type of heart failure, and left atrial volume index.

METHODS

Our primary outcome of interest was arrhythmia recurrence.

RESULTS

During a mean follow-up of 29 months, arrhythmia recurrence was observed in 65% of the morbidly obese cohort compared to 27% of the control group (P < .0001). Among those with morbid obesity, sleep apnea screening, and treatment (91% vs 40%; P < .0001), blood pressure control (62% vs 53%; P = .001), glycemic control (85% vs 56%; P = .004), and weight loss more than equal to 5% (33% vs 57% in those who lost less than 5% and 83% in those who gained weight, P < .0001) were associated with lower arrhythmia recurrence. Recurrent arrhythmia was observed in one (4%) patient who accomplished all four goals, compared to 36% who achieved 3 of 4, 85% who modified 2 of 4%, and 97% of those who modified zero or one risk-factor. Risk-factor modification (RFM) was also associated with substantial reductions in the need for repeat ablation or direct-current cardioversion and arrhythmia-related hospitalization (P < .0001).

CONCLUSION

RFM through pragmatic noninvasive means such as blood pressure and glycemic control, sleep apnea screening and treatment, and weight loss is associated with substantially lower rates of recurrent arrhythmia among morbidly obese patients undergoing AF ablation.

Impact of Bariatric Surgery on Atrial Fibrillation Type

Background:

Obesity is an independent risk factor for atrial fibrillation (AF) and is associated with a higher AF burden. Recently, weight loss has been found to be associated with a significant reversal in AF type. Bariatric surgery (BS) is associated with reductions in inflammation, left atrial and ventricular remodeling, sleep apnea, blood pressure, and improved glycemic control, all of which may reduce AF burden. In this study, we sought to determine the impact of BS on AF type.

Methods:

We studied AF type before and after BS in 220 morbidly obese patients (body mass index, ≥40 kg/m 2 ). All patients underwent extended outpatient cardiac rhythm monitoring within 12 months of BS and at least 1 year after BS.

Results:

There was a significant reduction in body mass index following BS from 49.7±9 to 37.2±9 kg/m 2 . Weight loss was the greatest in the gastric bypass group with a mean percentage weight loss of 25% compared with 19% in patients who underwent sleeve gastrectomy and 16% following gastric banding ( P <0.0001). Significant reductions in CRP (C-reactive protein), NT-proBNP (N-terminal pro-B-type natriuretic peptide), HbA1C (glycated hemoglobin), and systolic blood pressure were observed in all 3 groups. Reversal of AF type occurred in 71% of patients following gastric bypass, 56% of patients who underwent sleeve gastrectomy, and 50% of patients following gastric banding ( P =0.004). On Cox proportional hazards analyses, percentage weight loss was significantly associated with AF reversal ( P =0.0002).

Conclusions:

BS is associated with significant reductions in weight, inflammatory markers, blood pressure, and AF type, and the beneficial effects appear to be the greatest in those undergoing gastric bypass surgery. This study further exemplifies the importance of weight loss and risk factor modification in AF management.

Association Between Pre-Ablation Glycemic Control and Outcomes Among Patients With Diabetes Undergoing Atrial Fibrillation Ablation

OBJECTIVES

The aim of this study was to investigate the impact of improved glycemic control on atrial fibrillation (AF) recurrence rates after ablation.

BACKGROUND

Diabetes is associated with increased rates of AF. The impact of improved pre-ablation glycemic control remains unknown.

METHODS

The 12-month pre-ablation trends in glycemic control were studied in 298 patients with diabetes undergoing AF ablation. Recurrence data were obtained during a mean follow-up period of 25.92 ± 20.26 months post-ablation.

RESULTS

Higher glycated hemoglobin (HbA_1c) at the time of ablation was associated with higher post-ablation recurrence rates. More than two-thirds (68.75%) of patients with HbA_1c >9% at the time of ablation developed recurrent AF, compared with 32.4% of those with HbA_1c <7% (p < 0.0001). On multivariate analysis, only the 12-month trend in HbA_1c was significantly associated with AF recurrence. Although 91.1% of patients with a worsening trend in HbA_1c during the 12 months prior to ablation developed recurrent AF, only 2% of patients with improvements in HbA_1c of 10% or more experienced AF recurrence (p < 0.0001).

CONCLUSIONS

The trend in glycemic control prior to ablation predicts arrhythmia recurrence after ablation. A multidisciplinary approach to reduce HbA_1c is imperative in patients with diabetes with AF to reduce recurrence rates after ablation.

Comparative study of levobupivacaine and bupivacaine for bilateral maxillary nerve block during pediatric primary cleft palate surgery: a randomized double-blind controlled study

Background

Cleft lip and palate are common major congenital anomalies. Cleft palate (CP) repair causes pain and needs large doses of intravenous opioids. The risk of postoperative airway obstruction or respiratory depression is high, requiring continuous and vigilant monitoring. The primary outcome was to evaluate the efficacy of using different local anesthetics during bilateral maxillary nerve block (MNB) with general anesthesia on quality of recovery after primary CP repair. We hypothesized that levobupivacaine would be better than bupivacaine. Also, to investigate the potency of bilateral MNB in improving quality of postoperative analgesia.

Methods

Sixty children undergoing primary CP repair surgery were enrolled in the study. Combined general anesthesia and regional bilateral MNB were used for all patients. Group L (n = 30): children received 0.15 ml/kg of 0.2% levobupivacaine, while in Group B (n = 30): children received 0.15 ml/kg of 0.2% bupivacaine.

Results

Face, Legs, Activity, Cry, and Consolability pain score readings were 0 score in 7 cases of the Group L and 10 cases of Group B, 1 score in 14 cases of the Group L and 12 cases of Group B, and 2 score in 9 cases of the Group L and 8 cases of Group B. We found no statistically significant difference between the two study groups as regarding pain score or serious complications.

Conclusions

Levobupivacaine is as effective and safe as bupivacaine to be used for MNB block with a lower incidence of complications. Bilateral suprazygomatic MNB is an effective, easy, and safe method for pain relief in children undergoing primary cleft palate repair surgeries.

SUTURE VERSUS FIBRIN GLUE MICRONEURAL ANASTOMOSIS OF THE FEMORAL NERVE IN SPRAGUE DEWLY RAT MODEL. A COMPARATIVE EXPERIMENTAL ASSESSMENT OF THE CLINICAL, HISTOLOGICAL AND STATISTICAL FEATURES

INTRODUCTION

Peripheral nerve injury is a frequently encountered clinical problem that leads to functional losses at the long-term. Although microsurgical repair has been introduced to clinical practice in peripheral nerve injuries, unsatisfactory outcomes regarding functional recovery in target organ cause an increasing interest on studies about nerve injury and biology of the recovery in nerve injuries1.

MATERIAL AND METHODS

Sciatic nerves of seventy adult Sprague Dewly rats were transected and primary anastomosis was performed. Rats were then divided into three groups: Control group, while 30 rats were repaired with sutures, and the remaining 30 were repaired with fibrin glue. After 30 days the rats were sacrified and the sciatic nerves were investigated histologically with morphometrical and statistical analyses.

RESULTS

In microsurgical nerve repair, suture placement has been thought to cause hindrance to the sprouting axons and compress the blood supply to the fascicles, thereby impairing the regeneration of the transected nerve ends after repair, with possible neuroma formation. On the other hand, fibrin glue is a simple, effective technique, less time consuming than suturing. Another advantage of this suture-free technique is that it avoids injuring the axon with needles, and the lack of foreign bodies minimizes the inflammatory reaction.

CONCLUSION

We recommend using fibrin glue as it demonstrates less inflammatory reaction, less scar tissue formation, it is less time consuming and provides better outcomes.

Management of upper ureteral stones exceeding 15 mm in diameter: Shock wave lithotripsy versus semirigid ureteroscopy with holmium:yttrium-aluminum-garnet laser lithotripsy

Objectives:

We conducted a retrospective study to evaluate the efficacy and outcome of shock wave lithotripsy versus semirigid ureteroscopy in the management of the proximal ureteral stones of diameter exceeding 15 mm.

Methods:

During the 2009−2014 study period, 147 patients presenting with the proximal ureteral stones exceeding 15 mm in diameter were treated. Both shock wave lithotripsy and ureteroscopy with laser lithotripsy were offered for our patients. A 6/8.9 Fr semirigid ureteroscope was used in conjunction with a holmium:yttrium–aluminum–garnet laser. The stone-free rate was assessed at 2 weeks and 3 months post-treatment. All patients were evaluated for stone-free status, operation time, hospital stay, perioperative complications, and auxiliary procedures.

Results:

Of the 147 patients who took part in this study, 66 (45%) had undergone shock wave lithotripsy and 81 (55%) underwent ureteroscopy. At the 3-month follow-up, the overall stone-free rate in the shock wave lithotripsy group was 39/66 (59%) compared to 70/81 (86.4%) in the ureteroscopic laser lithotripsy group. Ureteroscopic laser lithotripsy achieved a highly significant stone-free rate (p = 0.0002), and the mean operative time, auxiliary procedures, and postoperative complication rates were comparable between the two groups.

Conclusion:

In terms of the management of proximal ureteral stones exceeding 15 mm in diameter, ureteroscopy achieved a greater stone-free rate and is considered the first-line of management. Shock wave lithotripsy achieved lower stone-free rate, and it could be used in selected cases.

Abstract 472: Prevalence of Fredrickson-Levy Dyslipidemia Phenotypes at Extreme HDL-C Levels: The Very Large Database of Lipids (VLDL-9B)

Introduction: Big data techniques offer a novel opportunity to characterize individuals with extreme phenotypes. In this context, we aimed to describe the prevalence of classical Fredrickson-Levy dyslipidemia phenotypes at the extremes of HDL-C levels in a cross-sectional big data study.

Methods: We examined 848,801 U.S. adults and children from the Very Large Database of Lipids 1.0 who were referred for lipoprotein testing from 2009 to 2011. We categorized patients into HDL-C percentile categories (<0.1th, 0.1th to 99th to 99.9th, and >99.9th). We examined the prevalence of Fredrickson-Levy dyslipidemia phenotypes (I, IIa, IIb, III, IV and V) within these categories. We identified those who did not meet criteria for any classical dyslipidemia phenotype as the continuum group.

Results: Type I and V were mostly present at extremely low HDL-C levels. Type IIa was more prevalent in high vs. low HDL-C levels. Type III was 2-fold more prevalent in extremely low vs. high HDL-C levels. Type IV was the most prevalent classical dyslipidemia phenotype in our population, and was the most frequent at low HDL-C percentiles. About 50% of the extremely low and 90% of the extremely high HDL-C levels were classified into the continuum group.

Conclusion: In our cross-sectional big data analysis, there was a significantly higher prevalence of most classical dyslipidemia phenotypes at extremely low HDL-C compared with extremely high HDL-C levels. Only types I and V were more prevalent in extreme groups than general population. To some extent, very low HDL-C levels may be determined by inheritable, highly atherogenic dyslipidemias.

Abstract 361: Characterization of Lipoproteins in the Hypertriglyceridemic Fredrickson-Levy Dyslipidemic Phenotypes with Chylomicrons: The Very Large Database of Lipids (VLDL-7)

Background

The major dyslipidemia (DL) classes (I-V) are relatively rare with limited phenotypic characterization across large populations.

Methods

We studied 1,340,614 U.S. adults from the Very Large Database of Lipids and identified those with chylomicron (CM) excess (types I and V). Lipid testing was by ultracentrifugation (VAP, Atherotech, Birmingham, AL). The distributions of total cholesterol (TC), HDL-C, LDL-C and triglycerides (TG) in the database were superimposable with those in the NHANES 2007-2008 survey. We used the following criteria to classify the excess lipoprotein components of DL in subjects with TG >130 mg/dL: CM defined by TG/Total cholesterol (TC) ratio > 9 only (Type I) and CM with >90th percentile VLDL-C (Type V). Subjects with types II, III, or IV DL were excluded.

Results

Type I DL was characterized by very high TG and very low HDL-C, LDLr-C, non-HDL-C and normal VLDL-C and RLP-C. Type V was characterized by TG approximately twice that of type I, low HDL-C and LDLr-C, and elevated VLDL-C, RLP-C and non-HDL-C. The VLDL3-C/IDL-C ratio was approximately 2, twice that of the non-CM groups (Table).

Summary

To our knowledge, this is the largest single report of subjects with these rare hyper-CM phenotypes. The findings support the mechanism of reduced CM clearance and impaired conversion of VLDL to IDL and LDL. The marked reduction in HDL-C is consistent with cholesterol ester transport protein mediated TG-Cholesterol ester exchange between CM and apoB100 lipoproteins.

Abstract 362: Characterization of Triglyceride-Rich Remnant Lipoproteins in the Hypertriglyceridemic Fredrickson-Levy Dyslipidemic Phenotypes without Chylomicrons: The Very Large Database of Lipids (VLDL-6)

Background

The major dyslipidemia (DL) classes are relatively rare with limited phenotypic characterization across large populations.

Methods

We studied 1,340,614 U.S. adults from the Very Large Database of Lipids. Lipid testing was by ultracentrifugation (VAP, Atherotech, Birmingham, AL). Distributions of total cholesterol (TC), HDL-C, LDL-C and triglycerides (TG) in the database were superimposable with those in the NHANES 2007-2008 survey. We used the following criteria to classify the excess lipoprotein components of DL in subjects with TG >130 mg/dL without chylomicrons (CM): VLDL-C or LDLr-C (directly measured LDL-C - Lp(a)-C -IDL-C) > 90 th percentile, Type III DL remnant lipoprotein cholesterol (RLP-C = VLDL3-C + IDL-C) excess by criterion of VLDL-C/TG > 0.3. The remaining subjects (continuum) not classified by DL criteria were further stratified by TG/HDL-C <3 vs. >3, associated with insulin resistance.

Results

VLDL3-C/ IDL-C ratio was approximately 1 across DL and the continuum groups. The highest concentration of RLP-C was in Type III DL; lesser RLP-C elevation is present in all DL characterized by VLDL excess. The highest non-HDL-C was present in type IIb with lesser elevations in types III and IV. RLP-C was higher in the TG/HDL-C>3 continuum than TG/HDL-C<3 continuum reference group (Table).

Summary

In addition to type III, the major non-CM DL is frequently associated with excess RLP-C. RLP-C tended to be normal in the continuum subjects, trending higher in those with TG/HDL-C>3.

Abstract 442: Correlates of the Triglyceride/HDL Cholesterol Ratio: The Very Large Database of Lipids (VLDL-4)

Background

The Triglyceride/HDL Cholesterol Ratio (TG/HDL-C) is predictive of atherosclerosis and vascular disease risk. It is frequently elevated in the metabolic syndrome and diabetes and tracks with measures of insulin resistance.

Methods

We investigated the correlates of TG/HDL-C in 3,609 serial subjects of the 1,340,614 U.S. adults from the VLDL dataset who had apoB, hsCRP, serum insulin levels, hemoglobin A1C (A1C) measurements in addition to ultracentrifugation lipid measurement by VAP method (Atherotech, Birmingham, AL). A continuous LDL density parameter (LLDR) was calculated as the natural log of the ratio of dense to buoyant LDL-C subfractions. Remnant lipoprotein cholesterol (RLP-C) was defined as dense remnant VLDL3-C + IDL-C. TG/HDL-C was modeled using multiple linear regression.

Results

The strongest correlates of TG/HDL-C in model 1 were serum insulin, RLP-C, LLDR and Lp(a)-C with overall model r=0.801, adjusted r2=0.641, p<0.001. Model 2 substituted dense VLDL3-C and IDL-C individually as independent variables in lieu of their sum, RLP-C; overall model r=0.855, adjusted r2=0.730, p<0.001. IDL-C was inversely correlated while VLDL3-C was more strongly and positively associated with TG/HDL-C. A1C was not significantly correlated in the multivariate models (Table).

Summary

TG/HDL-C ratio represents a composite of metabolic and lipid atherosclerosis risk markers including insulin levels, LDL density, RLP-C, lp(a)-C, homocysteine, gender and apoB.

A systematic review of hepatitis C virus epidemiology in Asia, Australia and Egypt

BACKGROUND

The hepatitis C pandemic has been systematically studied and characterized in North America and Europe, but this important public health problem has not received equivalent attention in other regions.

AIM

The objective of this systematic review was to characterize hepatitis C virus (HCV) epidemiology in selected countries of Asia, Australia and Egypt, i.e. in a geographical area inhabited by over 40% of the global population.

METHODOLOGY

Data references were identified through indexed journals and non-indexed sources. In this work, 7770 articles were reviewed and 690 were selected based on their relevance.

RESULTS

We estimated that 49.3-64.0 million adults in Asia, Australia and Egypt are anti-HCV positive. China alone has more HCV infections than all of Europe or the Americas. While most countries had prevalence rates from 1 to 2% we documented several with relatively high prevalence rates, including Egypt (15%), Pakistan (4.7%) and Taiwan (4.4%). Nosocomial infection, blood transfusion (before screening) and injection drug use were identified as common risk factors in the region. Genotype 1 was common in Australia, China, Taiwan and other countries in North Asia, while genotype 6 was found in Vietnam and other Southeast Asian countries. In India and Pakistan genotype 3 was predominant, while genotype 4 was found in Middle Eastern countries such as Egypt, Saudi Arabia and Syria.

CONCLUSION

We recommend implementation of surveillance systems to guide effective public health policy that may lead to the eventual curtailment of the spread of this pandemic infection.