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A major source of anthropogenic polycyclic aromatic hydrocarbon (PAH) inputs into marine environments are diffuse emissions which result in low PAH concentrations in the ocean water, posing a potential threat for the affected ecosystems. However, the remediation of low-dosage PAH contaminations through microbial processes remains largely unknown. Here, we developed a process-based numerical model to simulate batch cultures receiving repeated low-dosage naphthalene pulses compared to the conventionally used one-time high-dosage. Pulsing frequency as well as dosage concentration had a large impact on the degradation efficiency. After 10 days, 99.7%, 97.2%, 86.6%, or 83.5% of the 145 mg L -1 naphthalene was degraded when given as a one-time high-dosage or in 2, 5, or 10 repeated low-concentration dosages equally spaced throughout the experiment, respectively. If the simulation was altered, giving the system that received 10 pulses time to recover to 99.7%, pulsing patterns affected the degradation of naphthalene. When pulsing 10 days at once per day, naphthalene accumulated following each pulse and if the degradation was allowed to continue until the recovered state was reached, the incubation time was prolonged to 17 days with a generation time of 3.81 days. If a full recovery was conditional before the next pulse was added, the scenario elongated to 55 days and generation time increased to 14.15 days. This indicates that dissolution kinetics dominate biodegradation kinetics, and the biomass concentration of PAH-degrading bacteria alone is not a sufficient indicator for quantifying active biodegradation. Applying those findings to the environment, a one-time input of a high dosage is potentially degraded faster than repeated low-dosage PAH pollution and repeated low-dosage input could lead to PAH accumulation in vulnerable pristine environments. Further research on the overlooked field of chronic low-dosage PAH contamination is necessary., (© 2023. The Author(s).)

Background: Laparoscopy has enjoyed improvements over the last three decades primarily in achieving high definition, but the 70° field of view (FOV) remains unchanged. Complications related to events that take place out of the FOV continue to be reported. Additional problems leading to poor visualization are fogging and smoke accumulation. A novel laparoscopic system (SurroundScope, 270Surgical) was developed and dramatically expands the FOV from the 70° to 270° by adding side cameras at the distal tip of the laparoscope, while LED illumination eliminates fogging and improves smoke effects. This study describes the initial clinical experience with SurroundScope and its potential advantages over traditional laparoscopy., Methods: SurroundScope was studied at Bnai Zion Medical Center in Israel and the Minnesota Institute for Minimally Invasive Surgery in America. 27 laparoscopic surgeries were performed, and at the end of each procedure, evaluations were completed by all surgeons and camera holders., Results: All 27 cases were completed successfully without adverse events. No injuries occurred as a result of surgical tool manipulation outside of the central frame while 133 potentially adverse events were identified on side frames. There was no fogging across the 27 cases. The impact of smoke was negligible in all cases, as laparoscope removal or venting was never necessary. Surgeon respondents indicated that tools could be followed from the port to the site of surgery without camera manipulation. Most surgeons strongly agreed that the potential to identify bleeding was improved. Camera holders strongly agreed that the ergonomics were improved and that they moved the camera less than with a standard laparoscope., Conclusions: Initial results demonstrate numerous advantages for SurroundScope as compared to traditional laparoscopy. The important benefits of expanded FOV, complete lack of fogging, and negligible smoke may improve patient safety, reduce adverse events and the duration of surgery. Further investigation to quantify these benefits is recommended., (© 2021. The Author(s), under exclusive licence to Springer Science+Business Media, LLC, part of Springer Nature.)

Background: Male patients undergoing bariatric surgery have (historically) been considered higher risk than females. The aim of this study was to examine the disparity between genders undergoing laparoscopic sleeve gastrectomy (SG) and laparoscopic Roux-en-Y gastric bypass (RYGB) procedures and assess gender as an independent risk factor., Methods: The MBSAQIP® Data Registry Participant User Files for 2015-2017 was reviewed for patients having primary SG and RYGB. Patients were divided into groups based on gender and procedure. Variables for major complications were grouped together, including but not limited to PE, stroke, and MI. Univariate and propensity matching analyses were performed., Results: Of 429,664 cases, 20.58% were male. Univariate analysis demonstrated males were older (46.48 ± 11.96 vs. 43.71 ± 11.89 years, p < 0.0001), had higher BMI (46.58 ± 8.46 vs. 45.05 ± 7.75 kg/m 2 , p < 0.0001), and had higher incidence of comorbidities. Males had higher rates of major complications (1.72 vs. 1.05%; p < 0.0001) and 30-day mortality (0.18 vs. 0.07%, p < 0.0001). Significance was maintained after subgroup analysis of SG and RYGB. Propensity matched analysis demonstrated male gender was an independent risk factor for RYGB and SG, major complications [2.21 vs. 1.7%, p < 0.0001 (RYGB), 1.12 vs. 0.89%, p < 0.0001 (SG)], and mortality [0.23 vs. 0.12%, p < 0.0001 (RYGB), 0.10 vs. 0.05%; p < 0.0001 (SG)]., Conclusion: Males continue to represent a disproportionately small percentage of bariatric surgery patients despite having no difference in obesity rates compared to females. Male gender is an independent risk factor for major post-operative complications and 30-day mortality, even after controlling for comorbidities.

Introduction: The use of non-narcotic modalities for postoperative analgesia may decrease exposure to opioids, thereby limiting their deleterious effects. The objective of this study was to determine the effectiveness of a liposomal bupivacaine transverse abdominis plane (TAP) block prior to laparoscopic sleeve gastrectomy (LSG) and laparoscopic gastric bypass (LRYGB). The primary outcome was total postoperative morphine equivalents., Methods: A single-surgeon, IRB-approved retrospective chart review was performed on consecutive patients who underwent LRYGB or LSG from 2010 to 2016. Patients were grouped according to those who received TAP blocks immediately preoperatively with rescue opioids (TAP group) and those who received PCA only (PCA group). Total parenteral morphine equivalents (PME) were calculated. Numerical pain scores were collected immediately following surgery, 12 h postoperatively, and on the day of discharge. Median length of stay (LOS) and 30-day readmissions were also calculated., Results: There were 440 patients who met inclusion criteria. The TAP group had significantly less opioid use (total PME) than the PCA, irrespective of surgical approach (70.4 ± 2.7 PCA LRYGB and 26.5 ± 1.5 TAP block LRYGB, p value ≤ 0.0001; 60.0 ± 3.5 PCA LSG vs. and 24.1 ± 2.0 TAP block LSG, p value < 0.0001). Median LOS was 2.0 days for both PCA groups, whereas LOS decreased to 1.0 day for both groups of patients receiving TAP blocks (p < 0.0001). Pain scores immediately following and 12 h after surgery were significantly elevated in the TAP LRYGB versus PCA LRYGB (p < 0.05) and immediately following surgery for PCA versus TAP block for LSG (p = 0.0109)., Conclusions: TAP blocks with liposomal bupivacaine lead to significantly less use of parenteral morphine equivalents and decreased LOS compared to PCA alone. Pain scores were higher in the TAP LRYGB group compared to the LRYGB PCA group, with no differences in pain scores noted in the LSG groups.

Grasshoppers produce an extraordinary oviposition behavior that is associated with multiple specializations of the skeletal and neuromuscular systems in the posterior abdomen, including a central pattern generator (CPG) in the female's terminal abdominal ganglion. Two pairs of shovel-shaped appendages, the ovipositor valves on the abdomen tip, excavate the soil for deposition of eggs. By contrast, the sexually monomorphic pregenital region of the abdomen is without appendages. Morphological homologues of ovipositor muscles and efferent neurons in the eighth abdominal segment are nevertheless present in pregenital segments of males and females. In both sexes, a robust rhythmic motor program was induced in pregenital segments by the same experimental methods used to elicit oviposition digging. The activity, recorded extracellularly, was oviposition-like in burst period (5-6 s) and homologous muscle phase relationships, and it persisted after sensory inputs were removed, indicating the presence of pregenital CPGs. The abdomen exhibited posterior-going waves of activity with an intersegmental phase delay of approximately 1 s. These results indicate that serially homologous motor systems, including functional CPGs, provided the foundation for the evolution of oviposition behavior.

Purpose: We have previously shown that stress prior to induction worsens clinical presentation and inflammatory parameters in a rat model of endometriosis. This study was designed to examine whether stress during the development of endometriosis can affect the growth of endometriotic implants through nerve growth and immune alterations., Methods: Endometriosis was surgically induced in female Sprague-Dawley rats by suturing uterine horn implants onto the small intestine mesentery. Two weeks later, one group of rats (endo-stress) was subjected to a 10-day swim stress protocol. Controls had no stress (endo-no stress) or sutures only and stress (sham-stress). On day 60, all rats were killed and examined for the presence of endometriotic vesicles. The size of each vesicle was measured. The uterus and colon were removed and assessed for damage, cell infiltration, and expression of nerve growth factor (NGF), its receptors (p75 and Tropomyosin receptor kinase A (Trk-A)/pTrk-A), and calcitonin gene-related peptide, a sensory fiber marker. A differential analysis of peritoneal fluid white blood cell count was performed., Results: Stress significantly increased endometriotic vesicle size but not colonic damage and increased infiltration of mast cells. Significantly increased expression of NGF and its receptors was found in the uterus of animals with endometriosis receiving stress., Conclusions: Stress stimulates the development of ectopic endometrial vesicles in an animal model of endometriosis and increases inflammatory cell recruitment to the peritoneum. In addition, stress promotes nerve fiber growth in the uterus.

Studies have examined how endometriosis interacts with the nervous system, but little attention has been paid to opioidergic systems, which are relevant to pain signaling. We used the autotransplantation rat model of endometriosis and allowed to progress for 60 days. The brain was collected and examined for changes in endogenous opioid peptides, mu opioid receptors (MORs), and the N-methyl-d-aspartate subunit receptor (NR1) in the periaqueductal gray (PAG), since both of these receptors can regulate PAG activity. No changes in endogenous opioid peptides in met- and leu-enkephalin or β-endorphin levels were observed within the PAG. However, MOR immunoreactivity was significantly decreased in the ventral PAG in the endometriosis group. Endometriosis reduced by 20% the number of neuronal profiles expressing MOR and reduced by 40% the NR1 profiles. Our results suggest that endometriosis is associated with subtle variations in opioidergic and glutamatergic activity within the PAG, which may have implications for pain processing., (© The Author(s) 2016.)

We have previously shown detrimental effects of stress in an animal model of endometriosis. We now investigated whether the ability to control stress can affect disease parameters. Endometriosis was surgically induced in female Sprague-Dawley rats before exposing animals to a controllable (submerged platform) or uncontrollable (no platform) swim stress protocol. Corticosterone levels and fecal pellet numbers were measured as an indicator of stress. Uncontrollable stress increased the number and size of the endometriotic cysts. Rats receiving uncontrollable stress had higher anxiety than those exposed to controllable stress or no stress and higher corticosterone levels. Uncontrollable stressed rats had more colonic damage and uterine cell infiltration compared to no stress, while controllable stress rats showed less of an effect. Uncontrollable stress also increased both colonic and uterine motility. In summary, the level of stress controllability appears to modulate the behavior and pathophysiology of endometriosis and offers evidence for evaluating therapeutic interventions., (© The Author(s) 2014.)

Background: Hepatocellular carcinoma (HCC) is a major global health burden. Although chronic, heavy alcohol abuse is an established risk factor for HCC, obesity is emerging as an increasingly important factor in HCC development. Given that other risk factors for HCC act synergistically to promote tumorigenesis, we investigated the effects of diet-induced obesity and chronic ethanol consumption on tumor progression., Methods: A diethylnitrosamine (DEN) mouse model of HCC was established and mice randomized to control (CD; 10 % kcal% fat) or high fat (HFD; 60 % kcal% fat diet) at 5 weeks of age. At 35 weeks, mice were randomized to 10/20 % ethanol (EtOH) in drinking water (alternate days), or drinking water (H2O) alone. Tumor incidence/size were measured and confirmed. Liver tissue was analyzed for oxidative stress and EtOH-metabolizing enzymes and serum analyzed for liver function and nutritional status., Results: DEN treatment induced HCC formation in 60 % CD-H2O mice (6 of 10), an effect exacerbated by HFD (89 %). Tumors in HFD animals occupied significantly more of the liver than mice on CD. EtOH-feeding did not impact HCC incidence or tumor size. HFD resulted in increased liver injury and liver:body weight ratio regardless of EtOH consumption. Increased tumor incidence was associated with elevated hepatic oxidative stress in the absence of changes in intrinsic antioxidant (glutathione) levels., Conclusions: Obesity independently promoted HCC formation in the absence or presence of a known hepatocarcinogen (DEN), and enhanced both number and size of hepatic tumors independent of chronic EtOH consumption in mice.

Background: Hepatocellular carcinoma (HCC) is a rapidly increasing cancer whose known risk factors are chronic ethanol abuse, viral hepatitis infection, and aflatoxin exposure. Obesity, an emerging HCC risk factor, is reaching epidemic proportions in developed nations. This study investigated the effects of diet-induced obesity (DIO) and chronic ethanol consumption on HCC progression in mice in vivo., Methods: In this study, C57BL/6 DIO mice and lean litter mates were maintained on a 60% (high-fat diet [HFD]) diet or a 10% (control diet [CD]) kcal% fat diet for 7 weeks before they were weaned to 10/20% ([v/v], alternating days) ethanol in drinking water (EtOH) or maintenance on drinking water (H(2)O) alone. Hepatic tumor formation was initiated by intrahepatic Hepa1-6 cell (6 × 10(6) cells) inoculation 6 weeks later via the mesenteric vein., Results: The animals receiving the HFD showed decreased tumor incidence and area of hepatic foci versus the CD animals maintained on H(2)O alone. The action of EtOH suppressed tumor incidence further in both the CD and the HFD mice. Serologic analysis showed no significant differences in liver enzymes among the groups. Protein analysis demonstrated increased P450 2E1 (CYP2E1) in the groups maintained on EtOH, an effect exacerbated by HFD. Reverse transcriptase-polymerase chain reaction (RT-PCR) analysis demonstrated increased tumor necrosis factor-alpha (TNF-α) expression in HFD HCC mice (H(2)O and EtOH) concomitant with decreased transforming growth factor-beta (TGF-β) expression., Conclusions: Although obesity and EtOH consumption are known risk factors for HCC initiation and development, the data in this study suggest that these factors impair progression of established tumors within the liver.

Women with endometriosis have significant emotional distress; however, the contribution of stress to the pathophysiology of this disease is unclear. We used a rat model of endometriosis to examine the effects of stress on the development of this condition and its influence on inflammatory parameters. Female Sprague-Dawley rats were subjected to swim stress for 10 consecutive days prior to the surgical induction of endometriosis by suturing uterine horn implants next to the intestinal mesentery (endo-stress). Sham-stress animals had sutures only, and an endo-no stress group was not subjected to the stress protocol. At the time of sacrifice on day 60, endometriotic vesicles were measured and colons assessed for macroscopic and microscopic damage. Colonic tissue and peritoneal fluid were collected for inflammatory cell analysis. Endometriosis, regardless of stress, produced a decrease in central corticotropin-releasing factor immunoreactivity, specifically in the CA3 subregion of the hippocampus. Prior exposure to stress increased both the number and severity of vesicles found in animals with endometriosis. Stress also increased colonic inflammation, motility, myeloperoxidase levels, and numbers of mast cells. In summary, prior stress may contribute to the development and severity of endometriosis in this animal model through mechanisms involving cell recruitment (eg, mast cells), release of inflammatory mediators, and deregulation of hypothalamic-pituitary axis responses in the hippocampus.

Background: The use of fluorescent proteins to label tumors is revolutionizing cancer research, enabling imaging of both primary and metastatic lesions, which is important for diagnosis, staging, and therapy. This report describes the use of fluorescence laparoscopy to image green fluorescent protein (GFP)-expressing tumors in an orthotopic mouse model of human pancreatic cancer., Methods: The orthotopic mouse model of human pancreatic cancer was established by injecting GFP-expressing MiaPaCa-2 human pancreatic cancer cells into the pancreas of 6-week-old female athymic mice. On postoperative day 14, diagnostic laparoscopy using both white and fluorescent light was performed. A standard laparoscopic system was modified by placing a 480-nm short-pass excitation filter between the light cable and the laparoscope in addition to using a 2-mm-thick emission filter. A camera was used that allowed variable exposure time and gain setting. For mouse laparoscopy, a 3-mm 0° laparoscope was used. The mouse's abdomen was gently insufflated to 2 mm Hg via a 22-gauge angiocatheter. After laparoscopy, the animals were sacrificed, and the tumors were collected and processed for histologic review. The experiments were performed in triplicate., Results: Fluorescence laparoscopy enabled rapid imaging of the brightly fluorescent tumor in the pancreatic body. Use of the proper filters enabled simultaneous visualization of the tumor and the surrounding structures with minimal autofluorescence. Fluorescence laparoscopy thus allowed exact localization of the tumor, eliminating the need to switch back and forth between white and fluorescence lighting, under which the background usually is so darkened that it is difficult to maintain spatial orientation., Conclusion: The use of fluorescence laparoscopy permits the facile, real-time imaging and localization of tumors labeled with fluorescent proteins. The results described in this report should have important clinical potential.