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In this case, we discuss emergent small bowel resection and reanastomosis for a closed loop small bowel obstruction in the setting of recent bevacizumab exposure. Bevacizumab is a humanized monoclo...

Objectives: The objective of this retrospective review was to assess barriers to successful clinical trial enrollment among gynecologic cancer patients at a comprehensive cancer center. Methods: A retrospective chart review was performed of all new patients and established patients requiring treatment changes seen in a clinic setting by physicians in the gynecologic oncology department at a national cancer institute between July 1, 2019, and June 30, 2020. Demographic information collected for each patient included age, race, language, distance from the cancer center, insurance type, marital status, education, performance status and medical history. Demographic factors were compared between patients who enrolled in trials and those who were deemed eligible for clinical trials but did not enroll. Patients who did not enroll in a clinical trial were stratified by the reason for not enrolling as physician factor, patient factor, trial factor, and screening failure. Data was collected in a secure REDCap database. Data was analyzed using the Wilcoxon rank sum test and Fisher's exact test. Results: 960 records were reviewed and 165 patients were found to be eligible for a clinical trial at the time of their visit. 35 of these 165 patients (21.2%) enrolled in a clinical trial. Among patients who did not enroll in a clinical trial, the reasons for not doing so were due to a physician factor (71/130 or 55%), patient factor (42/130 or 32%), screening failure (13/130 or 10%), or a trial factor (4/130 or 3%). There were no significant differences in demographics between patients who enrolled in trials and those who did not. Patients who did not enroll secondary to a physician factor differed significantly from those enrolled or attempted to enroll in age and insurance type. Patients who did not enroll secondary to a physician factor were older when compared to those who enrolled or attempted to enroll in a clinical trial but failed the screening process (median of 70 vs 61.5 years old, p=0.014). They were also more likely to have Medicare and less likely to have private insurance (p=0.044). Patients who did not enroll secondary to a patient factor did not appear to differ significantly from patients who did enroll or who failed screening. Although patients who did not enroll secondary to a patient factor lived a mean distance almost twice as far away as those who enrolled or attempted to enroll (mean of 184 vs 91 miles), this was not statistically significant (p=0.107). Conclusions: Based on a one year time span of retrospective review, including the COVID 19 pandemic time, physician factor and concern for a patient's age appears to be the biggest barrier to clinical trial enrollment. Exploring additional reasons behind physicians’ reluctance to enroll patients in trials may be the key to increasing clinical trial enrollment of eligible patients.

Background Hysterectomies are the most common benign gynecologic surgical procedures performed in the United States. Currently, there are no tissue models that exist to teach trainees the techniques for colpotomy during laparoscopic hysterectomy. To address this educational gap, we have created a laparoscopic colpotomy model using a porcine stomach attached to a uterine manipulator. Methods A segment of a porcine stomach is secured onto a uterine manipulator to simulate the cervicovaginal junction. A uterus model created with craft materials and reused in subsequent sessions is placed above the porcine stomach onto the uterine manipulator tip. Porcine stomach was obtained from a local butcher or meat market costing less than $1.00 per model. The tissue can be refrigerated or frozen for storage, then thawed before each use. This model can be used with any energy device and any laparoscopic platform to teach and perform the colpotomy. Usability survey showed that trainees responded positively to the model and attendings thought it was a useful teaching tool. Experience Trainees and faculty responded favorably to the model and stated that the use of actual tissue enhanced the realism of a colpotomy simulation. Conclusion The porcine stomach laparoscopic colpotomy model is an innovative, low-cost teaching tool to add to a gynecologic surgical education simulation toolkit.

In the US, obesity rates are increasing greatly. The Centers for Disease Control and Prevention estimates that 68.5% of Americans, including 63.9% of adult women older than 20 years, are overweight (body mass index between 25 kg/m2 and 29.9 kg/m2) or obese (body mass index >30 kg/m2). In light of this, it is not surprising that the rates of bariatric surgery have also been increasing. When considering the metabolic changes associated with both bariatric surgery and contraceptive use, in combination with the unique medical considerations of obese women, it is indisputable that clear guidelines are needed when counseling obese patients of reproductive age after bariatric surgery. In this literature review, we focus on depot medroxyprogesterone acetate (DMPA) and the implications of its use in obese women, preweight and postweight loss following bariatric surgery. Both DMPA use and bariatric surgery are known to cause bone loss, but it is still unclear whether there is an additive effect of the two factors on bone loss and whether either of these factors directly leads to an increased risk of bone fracture. The current consensus guidelines do not impose a restriction on the use of DMPA after bariatric surgery. DMPA use is associated with weight gain, and it is unclear whether weight loss blunting occurs with the use of DMPA after bariatric surgery. Prior studies had demonstrated an association with weight gain in adolescents, and therefore, those prescribing DMPA use after bariatric surgery in adolescents should proceed with caution. Adult women do not have a similar response to the use of DMPA. DMPA use has rarely been associated with increased risk of venous thromboembolism (VTE). The obesity-associated increase in VTE should be mitigated by surgically induced weight loss. The concurrent use of DMPA in the post bariatric surgical period should not further increase the risk of VTE.

e18067 Background: Concern for toxicities in obese ovarian cancer patients may limit weight-based chemotherapy dosing, which has been associated with poor survival. We sought to evaluate the impact of obesity on treatment and outcomes by race/ethnicity at a National Cancer Institute (NCI)-designated Comprehensive Cancer Center (CCC). Methods: 66 minority (non-Hispanic black, Hispanic) epithelial ovarian cancer patients diagnosed 2006 and treated with frontline chemotherapy were frequency matched to two non-Hispanic white (NHW) patients by 5-year age group and stage (n = 198). For frontline carboplatin, relative dose intensity (RDI) was calculated by dividing the dose received by the expected dose, with an RDI < 0.85 indicating carboplatin dose reduction. Patient characteristics and RDI were compared by obesity and race/ethnicity. Cox proportional hazards regression was used to estimate hazard ratios (HR) and 95% confidence intervals (CI) for the association between obesity, race/ethnicity and RDI with mortality, adjusting for confounders. Results: Minorities were more likely to be obese, underinsured, and to experience delays in chemotherapy compared to NHW. Compared to normal/overweight patients, obese patients were more likely to experience carboplatin under dosing in the neoadjuvant (p = 0.004) and adjuvant (p < 0.0001) setting, but there were no differences in RDI by race/ethnicity or toxicities. No association with survival was observed for dose reduction and BMI. Compared to NHW, minorities had similar survival in the first 4 years after diagnosis (HR = 0.99, 95% CI = 0.60-1.63), but an increased risk of mortality > 4 years after diagnosis (HR = 4.07, 95% CI = 1.92, 8.60). Conclusions: Even though minorities were more likely to be obese, there were no differences in dosing by race/ethnicity at an NCI CCC. Minorities had similar survival to NHW in the first 4 years after diagnosis, likely due to similar access to quality care at an NCI CCC. However, > 4 years after diagnosis, the racial/ethnic survival disparity persisted after adjustment for clinical and pathologic characteristics. Expansion of this work to other patient populations may help determine if findings are similar outside of a tertiary care center.

A novel, low-cost and direct green synthesis strategy was developed for the preparation of polymer composite spheres composed of silver nanoparticles (AgNPs) decorated on the polymer colloids in a raspberry-like fashion. The polymer colloids were employed as both the reductant and the substrate support. The environmentally benign reaction system consists of AgNO3, polymer spheres and an ethanol solvent, without any additional reducing agents or stabilizers. The obtained composite spheres are surprisingly stable. The size range of the formed AgNPs is from several to tens of nanometers, dependent on the reaction time, AgNO3 concentration, and the amount of polymer spheres. A four-step mechanism was proposed for the formation of AgNPs-coated polymer spheres emphasizing the role of ethanol for saturating the external surface of the polymer spheres first. These composites exhibit excellent antibacterial activity, which is dependent on both the concentration of the composite spheres and the size of coated AgNPs.

Mutations in polycystin-1 and transient receptor potential polycystin 2 (TRPP2) account for almost all clinically identified cases of autosomal dominant polycystic kidney disease (ADPKD), one of the most common human genetic diseases. TRPP2 functions as a cation channel in its homomeric complex and in the TRPP2/polycystin-1 receptor/ion channel complex. The activation mechanism of TRPP2 is unknown, which significantly limits the study of its function and regulation. Here, we generated a constitutively active gain-of-function (GOF) mutant of TRPP2 by applying a mutagenesis scan on the S4-S5 linker and the S5 transmembrane domain, and studied functional properties of the GOF TRPP2 channel. We found that extracellular divalent ions, including Ca(2+), inhibit the permeation of monovalent ions by directly blocking the TRPP2 channel pore. We also found that D643, a negatively charged amino acid in the pore, is crucial for channel permeability. By introducing single-point ADPKD pathogenic mutations into the GOF TRPP2, we showed that different mutations could have completely different effects on channel activity. The in vivo function of the GOF TRPP2 was investigated in zebrafish embryos. The results indicate that, compared with wild type (WT), GOF TRPP2 more efficiently rescued morphological abnormalities, including curly tail and cyst formation in the pronephric kidney, caused by down-regulation of endogenous TRPP2 expression. Thus, we established a GOF TRPP2 channel that can serve as a powerful tool for studying the function and regulation of TRPP2. The GOF channel may also have potential application for developing new therapeutic strategies for ADPKD.

Mutations in polycystin-1 and TRPP2 (transient receptor potential polycystin 2) account for almost all clinically identified cases of autosomal dominant polycystic kidney disease (ADPKD), one of the most common human genetic diseases. TRPP2 functions as cation channel when it is homomeric assembled, and when it forms a complex with polycystin-1. Studies on the function and regulation of TRPP2 are significantly delayed due to the lack of knowledge on its activation mechanism. Here, by applying a mutagenesis scan on the S4-S5 linker and the S5 transmembrane domain, we generated the constitutively active gain-of-function (GOF) mutant TRPP2_F604P and studied functional properties of this GOF channel.

The interleukin-8 (IL-8, CXCL8) chemokine, also known as the neutrophil chemotactic factor, is a cytokine that plays a key role in inflammatory response, cell proliferation, migration, and survival. IL-8 expression is increased not only in inflammatory disorders, but also in many types of cancer, including prostate cancer. IL-8 acts as a ligand for the C-X-C chemokine receptor 2 (CXCR2) protein present on the cell plasma membrane. Binding of the IL-8 ligand to the CXCR2 receptor results in an intracellular signaling pathway mediated by GTP binding proteins coupled to the receptor itself. Knowledge of the CXCR2 expression levels facilitates the understanding of the role and function of IL-8. In this chapter, we describe a protocol that uses the immunofluorescence method and confocal microscopy to analyze the CXCR2 surface expression in human prostate cancer cells. However, this protocol is easily adaptable to analyze the surface expression of other cytokine receptors in different cell types.

Cytokines are pleiotropic, low-molecular-weight proteins that regulate the immune responses to infection and inflammation. They stimulate the immune responses by binding to cytokine receptors on the cell plasma membrane. Thus, knowledge of the expression level of particular cytokine receptors on cell surface is crucial for understanding the cytokine function and regulation. One of the techniques to explore the membrane embedded cytokine receptors is cell surface biotinylation. Biotinylated surface proteins can be rapidly purified through the strong interaction between biotin and streptavidin. Here, we describe the procedure for surface biotinylation and purification of biotinylated cytokine receptors for further downstream analysis.

The interleukin-8 (IL-8, CXCL8) chemokine, also known as the neutrophil chemotactic factor, is a cytokine that plays a key role in inflammatory response, cell proliferation, migration, and survival. IL-8 expression is increased not only in inflammatory disorders, but also in many types of cancer, including prostate cancer. IL-8 acts as a ligand for the C-X-C chemokine receptor 2 (CXCR2) protein present on the cell plasma membrane. Binding of the IL-8 ligand to the CXCR2 receptor results in an intracellular signaling pathway mediated by GTP binding proteins coupled to the receptor itself. Knowledge of the CXCR2 expression levels facilitates the understanding of the role and function of IL-8. In this chapter, we describe a protocol that uses the immunofluorescence method and confocal microscopy to analyze the CXCR2 surface expression in human prostate cancer cells. However, this protocol is easily adaptable to analyze the surface expression of other cytokine receptors in different cell types.

Cytokines are pleiotropic, low-molecular-weight proteins that regulate the immune responses to infection and inflammation. They stimulate the immune responses by binding to cytokine receptors on the cell plasma membrane. Thus, knowledge of the expression level of particular cytokine receptors on cell surface is crucial for understanding the cytokine function and regulation. One of the techniques to explore the membrane embedded cytokine receptors is cell surface biotinylation. Biotinylated surface proteins can be rapidly purified through the strong interaction between biotin and streptavidin. Here, we describe the procedure for surface biotinylation and purification of biotinylated cytokine receptors for further downstream analysis.

Transient receptor potential channel polycystin subfamily (TRPP) proteins assemble with polycystic kidney disease (PKD) proteins to form functionally important complexes. For example, the TRPP2/PKD1 receptor-ion channel complex plays a critical role in renal physiology. Mutations in either protein cause autosomal dominant polycystic kidney disease (ADPKD), one of the most common genetic diseases in humans. A similar complex, assembled by TRPP3 and PKD1L3, is a candidate for the sour taste receptor. The TRPP2/PKD1 complex contains three TRPP2 subunits and one PKD1 subunit and the interaction between their C-termini is crucial for the complex assembly. The TRPP3/PKD1L3 complex has the same subunit stoichiometry but its assembly involves interactions between the transmembrane segments of both proteins. These interactions have been shown to be essential for the assembly, surface expression and function of the complexes. Here we find another novel binding site between these proteins. When co-expressed in HEK293T cells, the extracellular loops between the first and second transmembrane segments (I-II loop) of TRPP2 and TRPP3 associate with the extracellular loops between the sixth and seventh transmembrane segments (VI-VII loop) of PKD1 and PKD1L3 respectively. These loops can also associate with their binding partners when the latter is expressed as full-length proteins. The loop-loop associations are functionally crucial since expression of either the TRPP3 I-II loop or the PKD1L3 VI-VII loop shows dominate negative effect on the acid-induced current of TRPP3/PKD1L3 complex. These results demonstrate, for the first time, the previously unknown essential role that these extracellular loops play in the assembly of TRPP/PKD complexes.