Solvent Selection for Liquid-Liquid Extraction of Acetic Acid from Biomass Hydrolysate

Biofuels are one of the most hopeful alternative energy sources to fossil fuels. However, the processing and production of biofuels needs improvement to be economically competitive in the current market. One drawback is the presence of naturally occurring compounds that decrease the bioethanol production rate and yield; these are called inhibitors. A resolution to this problem is to remove the inhibitors from biomass fermentation broth prior to fermentation. This project examined liquid-liquid extraction (LLE) for removal of acetic acid, a major inhibitor. Initially, a stock solution of glucose, xylose, acetic acid, and water was combined with an additional organic solvent to form a two-phase system. After mixing, the concentrations of the components in the water phase were analyzed using high performance liquid chromatography (HPLC). The compounds remaining in the solvent-rich phase were calculated via a simple mass balance. Nine different organic solvents were tested with the same mixture of compounds, after which the four most effective solvents were tested with liquid fermentation broth. The four best solvents were: ethyl acetate, butyl acetate, ethyl propionate, and isobutyl acetate. These four solvents had the highest split fraction, meaning that the acetic acid separated in the desired direction into the organic solvent. Butyl acetate was the best solvent because it extracted the most acetic acid, while retaining the sugars within the aqueous phase. Further research must be done on the organic phase analysis to ensure that the compound mass balance is closed. This research can help promote a more efficient production of biofuel

Trainee participation and perioperative complications in benign hysterectomy: the effect of route of surgery

BACKGROUND: Intraoperative trainee involvement in hysterectomy is common. However, the effect of intraoperative trainee involvement on perioperative complications depending on surgical approach is unknown. OBJECTIVE: To estimate the effect of intraoperative trainee involvement on perioperative complication after vaginal, laparoscopic, and abdominal hysterectomy for benign disease. METHODS: Patients undergoing laparoscopic, vaginal, or abdominal hysterectomy for benign disease from 2010 to 2012 were identified from the American College of Surgeons National Surgical Quality Improvement Program database. Patients with and without trainee involvement were compared with regard to perioperative complications. Complications that occurred from the start of surgery to 30-days postoperatively were included. Perioperative complications were defined via the use of the validated Clavien-Dindo scale with ≥grade 3 complications defined as major and ≤grade 2 complications defined as minor. Major complications included myocardial infarction, pneumonia, venous thromboembolism, deep or organ space surgical-site infection, stroke, fascial dehiscence, unplanned return to the operating room, renal failure, cardiopulmonary arrest, sepsis, intubation greater than 48 hours, and death. Minor complications included urinary tract infection, blood transfusion, and superficial wound infection. To estimate the effect of trainee involvement depending on route of surgery, a stratified analysis was performed. Bivariable analysis and adjusted multivariable logistic regression were used. RESULTS: We identified 22,499 patients, of whom 42.1% had trainee participation. Surgical approaches were vaginal (22.7%), abdominal (47.1%), and laparoscopic (30.2%). The rate of major complication was 3.2%, and minor complication was 7.2%. In bivariable analysis, trainee involvement was associated with major complications in vaginal hysterectomy (3.3% vs 2.3%, P = .03), but not laparoscopic (3.0% vs 2.9%, P = .78) or abdominal hysterectomy (4.4% vs 3.6%, P = .07). Trainee involvement was also associated with minor complication in vaginal (7.3% vs 5.4%, P = .007), laparoscopic (5.9% vs 4.3%, P < .001), and abdominal hysterectomy (14.1% vs 9.2%, P < .001). In a multivariable analysis in which we adjusted for age, body mass index, medical comorbidity, American Society of Anesthesiologists score, and surgical complexity, the association between trainee involvement in vaginal hysterectomy and major complication persisted (adjusted odds ratio 1.45, 95% confidence interval 1.03-2.04); however, when operative time was added to the model, there was no longer an association between trainee involvement and major complication (adjusted odds ratio 1.26, 95% confidence interval 0.89-1.80). CONCLUSION: Surgical approach influences the relationship between trainee involvement and perioperative complication. Operative time is a key mediator of the relationship between trainee involvement and complication, and may be a modifiable risk factor

Venous Thromboembolism in Minimally Invasive Compared With Open Hysterectomy for Endometrial Cancer

OBJECTIVE: To evaluate whether minimally invasive surgery for endometrial cancer is independently associated with a decreased odds of venous thromboembolism compared with open surgery. METHODS: We performed a secondary analysis cohort study of prospectively collected quality improvement data and examined patients undergoing hysterectomy for endometrial cancer from 2008 to 2013 recorded in the National Surgical Quality Improvement Program database. Patients undergoing minimally invasive (laparoscopic or robotic) surgery were compared with those undergoing open surgery with respect to 30-day postoperative venous thromboembolism. Demographic and procedure variables were examined as potential confounders. Data regarding receipt of perioperative venous thromboembolism prophylaxis were not available. Bivariable tests and logistic regression were used for analysis. RESULTS: Of 9,948 patients who underwent hysterectomy for the treatment of endometrial cancer, 61.9% underwent minimally invasive surgery and 38.1% underwent open surgery. Patients undergoing minimally invasive surgery had a lower venous thromboembolism incidence (0.7%, n=47) than patients undergoing open surgery (2.2%, n=80) (P<.001). In a multivariate model adjusting for age, body mass index, race, operative time, Charlson comorbidity score, and surgical complexity, minimally invasive surgery remained associated with decreased odds of venous thromboembolism (adjusted odds ratio 0.36, 95% confidence interval 0.24-0.53) compared with open surgery. CONCLUSION: Minimally invasive surgery for the treatment of endometrial cancer is independently associated with decreased odds of venous thromboembolism compared with open surgery

The health-related quality of life journey of gynecologic oncology surgical patients: Implications for the incorporation of patient-reported outcomes into surgical quality metrics

To report the changes in patient-reported quality of life for women undergoing gynecologic oncology surgeries

Who presents satisfied? Non-modifiable factors associated with patient satisfaction among gynecologic oncology clinic patients

To examine associations between non-modifiable patient factors and patient satisfaction (PS) among women presenting to a gynecologic oncology clinic

Does the Robotic Platform Reduce Morbidity Associated With Combined Radical Surgery and Adjuvant Radiation for Early Cervical Cancers?

Open radical hysterectomy followed by adjuvant radiation for cervical cancer has been associated with significant rates of morbidity. Radical hysterectomy is now often performed robotically. We sought to examine if the robotic platform decreased the morbidity associated with radical hysterectomy followed by adjuvant radiation

Clinical Benefits Associated With Medicaid Coverage Before Diagnosis of Gynecologic Cancers

Many low-income patients enroll in Medicaid at the time of cancer diagnosis, which improves survival outcomes. Medicaid enrollment before cancer diagnosis may confer additional benefits. Our objective was to compare stage at diagnosis and overall mortality between women with and without Medicaid enrollment before gynecologic cancer diagnosis

A preoperative personalized risk assessment calculator for elderly ovarian cancer patients undergoing primary cytoreductive surgery

Cytoreductive surgery for ovarian cancer has higher rates of postoperative complication than neoadjuvant chemotherapy followed by surgery. If patients at high risk of postoperative complication were identified preoperatively, primary therapy could be tailored. Our objective was to develop a predictive model to estimate the risk of major postoperative complication after primary cytoreductive surgery among elderly ovarian cancer patients

The impact of surgical complications on health-related quality of life in women undergoing gynecologic and gynecologic oncology procedures: a prospective longitudinal cohort study

There are currently no assessments of the impact of surgical complications on health-related quality of life in gynecology and gynecologic oncology. This is despite complications being a central focus of surgical outcome measurement, and an increasing awareness of the need for patient-reported data when measuring surgical quality

In vivo characterization of connective tissue remodeling using infrared photoacoustic spectra

Premature cervical remodeling is a critical precursor of spontaneous preterm birth, and the remodeling process is characterized by an increase in tissue hydration. Nevertheless, current clinical measurements of cervical remodeling are subjective and detect only late events, such as cervical effacement and dilation. Here, we present a photoacoustic endoscope that can quantify tissue hydration by measuring near-infrared cervical spectra. We quantify the water contents of tissue-mimicking hydrogel phantoms as an analog of cervical connective tissue. Applying this method to pregnant women in vivo, we observed an increase in the water content of the cervix throughout pregnancy. The application of this technique in maternal healthcare may advance our understanding of cervical remodeling and provide a sensitive method for predicting preterm birth