Improving the Conversion Success Rate of Hepatocellular Carcinoma: Focus on the Use of Combination Therapy with a High Objective Response Rate

The high mortality rate in hepatocellular carcinoma (HCC) is partially due to the fact that a significant number of patients are diagnosed at an intermediate or advanced stage, with surgical treatment options unavailable. Conversion therapy, which involves both locoregional and systemic treatments, has the potential to downstage tumors in selected patients with initially unresectable HCC, thereby making surgical treatment a possibility and potentially increasing long-term survival. To optimize the conversion rate, it is necessary to maximize successful conversions and clearly define the target population for conversion treatment through a collaborative effort. In this review article, we summarize the clinical experience and evidence for conversion therapy in patients with 'potentially resectable' HCC from four perspectives: 1) defining the target population for conversion therapy, 2) selecting the appropriate conversion strategy, placing emphasis on the utilization of combination therapy that exhibits a significant objective response rate, 3) determining the timing and urgency of surgical resection, 4) promoting the adoption of a multidisciplinary team model. The authors are optimistic that with the continuous progress in treatment and a deeper understanding of HCC, the success rate of HCC conversion therapy will increase, and the overall survival of HCC patients will be prolonged.

Advancing laparoscopy in resource-limited settings

BACKGROUND

Although laparoscopic surgery has made remarkable progress and become the standard approach for various surgical procedures worldwide over the past 30 years, its establishment in low-resource settings, particularly in public hospitals, has been challenging. The lack of equipment and trained expertise has hindered its widespread adoption in these settings. Cholecystectomy is one of the most commonly performed procedures using laparoscopy world wide AIM: The aim of the study is to determine whether laparoscopic cholecystectomy is feasible in a resource challenged setting METHODS: The research focused on individuals who underwent laparoscopic or open cholecystectomies at Yekatit 12 Hospital in Addis Ababa, Ethiopia, over a one-year period. Comprehensive data collection was conducted prospectively, encompassing both intraoperative and postoperative parameters. Follow-up was carried out via phone calls. The surgical procedures employed innovative techniques, including the reuse of sterilized single-use equipment and the utilization of local resources. The evaluation involved a comparison of demographic information, intraoperative details (such as critical view determination and operative duration), and postoperative complications, including assessments of pain and wound infections RESULTS: From August 2021 to September 2022, 119 patients were assessed. Among these patients, 65 (54.6%) underwent open cholecystectomies, while the remaining 54 (45.4%) underwent laparoscopic cholecystectomies. The average duration of the laparoscopic cholecystectomies was 90.7 min, which is 17.7 min behind the open. Patients in the laparoscopy group had significantly shorter hospital stays than the open group, and 94% were discharged by post operative day 2. The conversion rate from laparoscopic to open surgery was determined to be 3.3% CONCLUSION: To sum up, the safe execution of laparoscopic cholecystectomies is feasible in public hospitals and settings with limited resources, given adequate training and resource distribution. The study findings showcased superior outcomes, including reduced hospitalization duration and fewer complications, while maintaining comparable levels of operative duration and patient satisfaction in both groups.

Single incision robotic myomectomy: selection criteria, learning curve and cost

The article "Comparison of operative and fertility outcomes of single-incision robotic myomectomy: a retrospective single-center analysis of 286 cases" by Kim et al. compares the effectiveness of robotic single-port myomectomy against the traditional multiport approach. The study finds similar operating outcomes, complication rates, and pregnancy rates in expert hands for both methods. Our systematic review supports these findings, revealing no significant differences in operative time, blood loss, or complication rates. Recent meta-analysis further emphasizes the benefits of the single-port approach in reducing morcellation time, overall operative duration, and blood loss. Our letter seeks insights on patient selection criteria to minimize conversion rates between surgical approaches and inquiries on learning curve differences. Additionally, we seek cost analysis details for both techniques. We appreciate the authors' valuable contributions to this field.

Challenges in the determination of total vitamin B12 by cyanidation conversion: insights from stable isotope dilution assays

Previous methods for vitamin B12 (B12) analysis have extensively used cyanidation conversion with the intention of converting all cobalamins to cyanocobalamin (CNCbl) for total B12 determination. This approach has been favored for its advantages in reducing the number of analytes, increasing analyte concentration, and improving analyte stability. However, the present study revealed underlying limitations associated with this approach. First, a stable isotope dilution assay (SIDA) determining total B12 as CNCbl after cyanidation conversion (conversion SIDA method) was developed. Method validation demonstrated good sensitivity, recovery, accuracy, and reproducibility for the target analyte CNCbl. However, subsequent application of the conversion method to real meat samples showed incomplete conversions of cobalamins. These inconsistencies revealed day-to-day variability and reliability challenges associated with the cyanidation process. It was not possible to identify this issue during method validation as CNCbl was spiked as the sole analyte and it requires no further cyanidation conversion. The application of LC-MS/MS enabled the detection of trace amounts of unconverted cobalamins. Nevertheless, this approach remains restricted by instrument sensitivity and stability as well as the performance of immunoaffinity purification for different vitamers. Further development of a reliable monitoring method is a prerequisite for further optimization of the cyanidation process. However, significant improvements of analytical instrumentation in terms of sensitivity and stability are required to overcome the current limitations.

Emergency versus elective cholecystectomy: Experience at a university hospital in the Eastern Province, Saudi Arabia

BACKGROUND

Laparoscopic cholecystectomy (LC), the procedure of choice for treating most gallbladder pathology, has become the most trusted elective procedure for treating gallstone disease because of its effectiveness and safety. While the timing is an important factor in those cases, our aim in this study was to compare emergency and elective LC, determine the differences in postoperative complications, and assess the conversion rate to open cholecystectomy.

MATERIALS AND METHODS

This study included a total of 627 patients who had undergone laparoscopic cholecystectomy during 2017-2019 at King Fahd Hospital of the University (KFHU). Records of both emergency and elective cases were reviewed from Quadra-med (software package). All demographic data of the patients, presenting complaint, laboratory and inflammatory marker, type of the operation, intraoperative complications, procedure time, conversion rate from laparoscopic to open cholecystectomy, postoperative period, length of hospital stay, and pathological diagnosis were entered into an Excel sheet. The data was analyzed using SPSS 23.0. Qualitative variables were described as frequencies and percentages, and continuous variables were summarized with mean and standard deviation (SD). Chi-square test, t-test, and the Mann-Whitney U-test were applied to test for statistical significance at P ≤ 0.05.

RESULTS

The mean age for patients undergoing elective LC was 39.94 years (SD=13.56) whereas, mean age of patients undergoing emergency LC was 40.64 years (SD=13.02). About 71% of cases in elective LC group were females compared to 55% in the emergency LC group. There was a significant difference in C-reactive protein (CRP) in relation to the type of surgery where P < 0.05. Twelve (1.9%) patients had subtotal cholecystectomy and two cases converted from LC to open. There was a significant association between postoperative complication and the type of surgery. The length of hospital stay (LOS) was also found to be significantly more in patients having emergency LC (6.0 vs. 4.5 d; P < 0.05).

CONCLUSION

The relation between conversion to an open procedure and type of surgery (elective or emergency) in our study was nonsignificant. There was a significant association between preoperative CRP, postoperative complication, length of hospital stay, and type of surgery. Further multicenter studies are required for further investigation.

Effect of thickness on the degree of conversion of two bulk-fill and one conventional posterior resin-based composites at high irradiance and high temporal resolution

OBJECTIVES

This study: 1) measures the effect of sample thickness and high irradiance on the depth-dependent time delay before photopolymerization reaction onset; 2) determines if exposure reciprocity exists; 3) measures the conversion rate at four irradiance levels; 4) determines the time, t0, at which the maximum DC rate is reached for two bulk-fill and one conventional posterior resin-based composites (RBCs).

METHODS

Tetric PowerFill IVA shade (Ivoclar Vivadent) and Aura bulk-fill ultra universal restorative (SDI), and one conventional posterior resin-based composite (RBC), Heliomolar A3 (Ivoclar Vivadent), that were either 0.2 mm, 2 mm, or 4 mm thick were photocured using a modified Bluephase G4 (Ivoclar Vivadent) light-curing unit (LCU) that delivered a single emission band (wavelength centered at 449 nm). The same radiant exposure of 24 J/cm2 was delivered at irradiances ranging from 0.5 to 3 W/cm2 by adjusting the exposure time. PowerFill was also photocured for 3 s or 6 s using a Bluephase PowerCure LCU (Ivoclar Vivadent) on the 3 s mode setting. The degree of conversion (DC) was measured in real-time at a high temporal resolution at 30 °C using Attenuated Total Reflection (ATR) FTIR spectroscopy with a sampling rate of 13 DC data points per second. The DC data were analyzed using a phenomenological autocatalytic model. The RBC viscosity was measured at 21 °C and 30 °C. Light transmission through the RBC samples at 22 °C was monitored with time to calculate the extinction coefficients of the RBCs.

RESULTS

The time delay before photopolymerization started increased as the RBC thickness increased and the irradiance decreased. An autocatalytic model described the DC data. The time t0 was less than 77 ms for the 0.2 mm thick samples of PowerFill irradiated using the highest irradiance of 3 W/cm2. Among the three RBCs for each sample thickness and irradiance level, the PowerFill had the smallest time t0. There was a time delay of 0.59 s and 1.25 s before the DC started to increase at the bottom of 4 mm thick samples for the PowerFill and Aura, respectively, when an irradiance of 1 W/cm2 was delivered. The time delay increased to 3.65 s for the Aura when an irradiance of 0.5 W/cm2 was delivered. The extinction coefficients near 449 nm were 0.78 mm-1, 0.76 mm-1, and 1.55 mm-1 during the first 2 s after the start of photocuring of PowerFill, Aura, and Heliomolar, respectively. Only PowerFill followed exposure reciprocity. At T = 30 °C, the viscosity was 3400, 17000, and 5200 Paˑs for PowerFill, Aura, and Heliomolar, respectively.

SIGNIFICANCE

The time delay between when photopolymerization starts at the top and bottom of 2- or 4-mm thick RBC restorations may affect the structural integrity of the bond between the tooth and the bottom of the restoration. Only PowerFill followed exposure reciprocity between irradiance levels of 0.5 to 3 W/cm2. Exposure reciprocity did not occur for Aura or Heliomolar, neither of which are optimized for short light exposure or high irradiance conditions.

Serial interferon-gamma release assay in lung cancer patients receiving immune checkpoint inhibitors: a prospective cohort study

Recent advancements in cancer immunotherapy using immune checkpoint inhibitors (ICIs) have received considerable attention. Although advantageous, ICI therapies cause unique immune-related adverse events (irAEs) in some patients. Moreover, infectious diseases, such as tuberculosis, have been recognized as emerging concerns during immunotherapy. We aimed to evaluate the interferon-gamma release assay (IGRA) conversion rate and active tuberculosis incidence during immunotherapy to elucidate the incidence of tuberculosis reactivation after ICI therapy induction.We prospectively assessed IGRA results in lung cancer patients who received ICI monotherapy before ICI treatment and at 6 and 12 months after ICI treatment. We also assessed computed tomography findings to determine the presence of active tuberculosis when positive IGRA results were obtained. The ICIs used were nivolumab, pembrolizumab, atezolizumab, and durvalumab.In all, 178 patients were prospectively recruited between March 2017 and March 2020. Of these, 123 completed serial IGRAs, of whom 18, 101, and 4, respectively, had positive, negative, and indeterminate IGRAs at baseline. Three and four patients, respectively, showed IGRA reversion and conversion during immunotherapy. One patient with a sustained, stable positive IGRA and one with IGRA conversion developed active pulmonary tuberculosis during immunotherapy.We found that 3.3% and 1.6% of the patients developed IGRA conversion and active tuberculosis, respectively. Of the four patients who developed IGRA conversion, one developed active pulmonary tuberculosis during immunotherapy. Another patient with sustained, stable positive IGRA developed active tuberculosis. Physicians should be alert to tuberculosis development during ICI therapy, and IGRA testing is a useful tool to assess the risk of developing active tuberculosis.

Impact of COVID-19 on the patient referral pattern and conversion rate in the university versus private facial plastic surgery centers

Purpose

To compare the number of referrals and conversion rate between the pandemic and pre-pandemic period.

Methods

The number of referrals and conversion rate between the 10-month pandemic (March–December 2020) and pre-pandemic (March–December 2019) were evaluated in the two university (mainly non-cosmetic) and private (mainly cosmetic) facial plastic surgery centers. Demographics and monthly number and type (cosmetic and non-cosmetic) of the referrals and surgeries were recorded from the both and cosmetic facial injections (botulinum toxin and filler) and the source of referrals (web- and non-web-based) from the private center. The conversion rate was a ratio of the number of the surgeries to the number of referrals.

Results

The number of referrals declined by 7.7% in the private center which was significantly higher for the non-cosmetic (26%) than the cosmetic (0.5%) referrals. It was 32% in the university center. The private center conversion rate significantly (P < 0.001) decreased for both the cosmetic (60%) and non-cosmetic (82%) procedures. It was not significantly different between the cosmetic (65%) and non-cosmetic (58%) procedures in the university center. However, the number of cosmetic facial injections (11%) and the web-based referral source (4%) increased. The recovery was better for the number of referrals (better in the private center) than the conversion rate.

Conclusion

The fall in the conversion rate was statistically significant in the private center. While the number of referrals recovered to almost the pre-pandemic level, the conversion rates, despite recovery, remained at a lower level at the end.

Supplementary Information

The online version contains supplementary material available at 10.1007/s10792-022-02469-1.

The use of telemedicine in pre-surgical evaluation: a retrospective cohort study of a neurosurgical oncology practice

Purpose

To determine if there was a discrepancy between telemedicine versus in-person New Patient Visits (NPVs) regarding the conversion rate to operative and radiosurgery cases at a tertiary surgical neuro-oncology practice.

Methods

A retrospective analysis was performed of patients who had an outpatient encounter with a neurosurgeon from the Tumor Division at our institution’s Department of Neurosurgery between February 1, 2021 and April 30, 2021. NPVs during this period were registered as either telemedicine or in-person appointments. The primary endpoint of the study was to compare the rate at which telemedicine NPVs and in-person NPVs underwent surgery or radiosurgery, reported as the surgical conversion rate.

Results

A total of 206 patients were included in this study. Of them, 119 (57.8%) were seen using telemedicine and 87 (42.2%) were seen in clinic via an in-person visit. A total of 70 (34%) of all patients underwent surgery or radiosurgery. Of the 119 patients seen via telemedicine, 40 (33.6%) underwent surgery or radiosurgery; during the same period, 87 NPVs were conducted in person and 30 (34.5%, p = 1.0) received an intervention. Further stratification revealed no differences between the two groups across measured criteria including diagnosis, number of pre-operative visits, elapsed time from appointment to surgery, follow-up visits, and distance from home address to neurosurgical clinic.

Conclusion

Telemedicine NPVs did not differ significantly from in-person NPVs when evaluating the likelihood of a new patient committing to surgical treatment. This study provides quantifiable evidence that telemedicine is an effective means of meeting new patients and planning complex neurosurgical interventions.

Robotic and laparoscopic surgical procedures for colorectal cancer

The study aims to investigate perioperative indices and immediate outcomes of laparoscopic and robotic surgical interventions in colorectal cancer patients. The study included 163 patients [90 (55.2%) females and 73 (44.8%) males, aged 67.46 ± 6.72 years, on average] who had surgery for morphologically checked colorectal cancer. Of those, 101 patients had laparoscopic surgery (Group 1), and 62 patients had robot-assisted surgery (Group 2). The study found that the safety profile of both robot and laparoscopic procedures for colorectal cancer is comparable. The total complication rate in the laparoscopic group was 6.9% (in 7 patients), in the robot-assisted group-11.3% (in 7 patients) (χ² = 0.93, p = 0.34). Robotic surgery for colorectal cancer is a promising direction for improving patients' level and quality of care with this oncological pathology.

Photo-polymerization kinetics of a dental resin at a high temporal resolution

OBJECTIVES

This study: 1) aims to measure with high temporal resolution the intrinsic rate of the degree of conversion (DC) of a dental resin-based composite (RBC) photo-cured at two irradiances; 2) aims to determine the transition time at which the DC rate is maximum; 3) used two different irradiances to measure the shift in transition time; 4) aims to compare transition times measured using DC and shrinkage strain.

METHODS

Samples (n = 20) 1 mm thick by 10 mm diameter of Filtek One bulk-fill restorative A2 shade (3M Oral Care) were photocured for 20 s with a single emission peak (wavelength centered at 455 nm) light-emitting-diode-based light-curing unit at irradiance levels of 890 mW/cm² and 209 mW/cm², and initial sample temperature of T = 23 °C. The DC was measured in real-time using Attenuated Total Reflection (ATR) FTIR spectroscopy with a sampling rate of 13 DC data points per second. The data were analyzed within a phenomenological autocatalytic model. In addition, the axial shrinkage strain was measured using 3 samples of the RBC with the same outer dimensions and under similar experimental conditions using the bonded disk method and an interferometric technique.

RESULTS

For the 890 mW/cm² and 209 mW/cm² irradiance levels, the DC with time was found to agree with the model enabling the determination of transition times of 0.66 ± 0.05 s and 2.3 ± 0.2 s, and the DC at these times of 5.5 ± 0.2% and 6.4 ± 0.2%. The maximum linear strain rate at 0.76 ± 0.01 s and 1.98 ± 0.02 s for the 890 mW/cm² and 209 mW/cm² irradiance levels, respectively, are within two standard deviations of the corresponding transition times.

SIGNIFICANCE

At an irradiance level much greater than 1000 mW/cm², the photo-polymerization kinetics of a dental RBC may be too fast to be measured accurately using ATR-FTIR spectroscopy. A viable alternative to monitor the kinetics is through the measurements of the axial shrinkage strain employing the bonded disk method and an interferometric technique.

Surgical outcome of percutaneous transhepatic gallbladder drainage in acute cholecystitis: Ten years' experience at a tertiary care centre

Background

Percutaneous transhepatic gallbladder drainage (PTGBD) plays an important role in the treatment of elderly patients and/or patients in poor health with acute cholecystitis (AC). The primary aim of this study is to determine how these factors influence the clinical outcome of PTGBD. Moreover, we assessed the timing and results of subsequent cholecystectomies.

Patients and Methods

We retrospectively examined the results of 162 patients undergoing PTGBD between 2010 and 2020 (male–female ratio: 51.23% vs. 48.77%; mean age: 71.43 ± 13.22 years). Patient’s performance status and intervention outcomes were assessed with clinical success rates (CSR) and in-hospital mortality. The conversion rate (CR) of possible urgent or delayed, elective laparoscopic cholecystectomies (LC) after PTGBD were analysed.

Results

PTGBD was the definitive treatment in 42.18% of patients, while it was a bridging therapy prior to cholecystectomy (CCY) for the other patients. CSR was 87.97%, it was only 64.29% in grade III AC. In 9.87% of the cases, urgent LC was necessary after PTGBD, and its conversion rate was approximately equal to that of elective LC (18.18 vs. 17.46%, respectively, p = 0.2217). Overall, the post-PTGBD in-hospital mortality was 11.72%, while the same figure was 0% for grade I AC, 7.41% for grade II and 40.91% for grade III. Based on logistic regression analyses, in-hospital mortality (OR 6.07; CI 1.79–20.56), clinical progression (OR 7.62; CI 2.64–22.05) and the need for emergency CCY (OR 14.75; CI 3.07–70.81) were mostly determined by AC severity grade.

Conclusion

PTGBD is an easy-to-perform intervention with promising clinical success rates in the treatment of acute cholecystitis. After PTGBD, the level of gallbladder inflammation played a decisive role in the course of AC. In a severe, grade III inflammation, we have to consider low CSR and high mortality.

[Robotic-assisted surgery of rectal cancer-Technique, limitations and results]

BACKGROUND

The number of oncological robotic-assisted rectal cancer resections is rapidly increasing in Germany and worldwide; however, the indications, technique and potential limitations of this surgical technique are still discussed.

MATERIAL AND METHODS

The standardized modular surgical technique, the results in our clinic and the currently published evidence are presented.

RESULTS

The procedure should be divided into seven modules in terms of standardization and teaching. After the learning curve there are principally no limitations or contraindications. The robotic-assisted approach is superior to open surgery in the following points: blood loss, lymph node harvest, negative circumferential resection margin (CRM), complication rate and length of hospital stay. In comparison to conventional laparoscopy the conversion rate and postoperative sexual and bladder function disorders are decreased. The operating time is longer.

CONCLUSION

Robotic-assisted rectal cancer resection is firmly established and standardized. The technique is superior to open surgery and conventional laparoscopy in some important aspects and is developing into the standard for this disease.

Role of laparoscopy in the treatment of internal biliary fistulas in a high-volume center and a review of the literature

BACKGROUND

Biliary fistulas may result as a complication of gallstone disease. According to their tract, abdominal internal biliary fistulas may be classified into cholecystobiliary and bilioenteric fistulas. Surgical treatment is challenging and requires highly trained surgeons with high preoperative suspicion. Conventional surgery is still of choice by most of the authors. However, laparoscopy is emerging as a minimally invasive alternative. We investigated the surgical approach, conversion rate, and outcomes according to the type of biliary fistula.

METHODS

We retrospectively reviewed 11,130 laparoscopic cholecystectomies, 31 open cholecystectomies, and 31 surgeries for gallstone ileus at our institution from May 2007 to May 2020. We diagnosed internal biliary fistula in 73 patients and divided them into two groups according to their fistulous tract: cholecystobiliary fistula and bilioenteric fistula. We described demographic characteristics, preoperative imaging modalities, surgical approach, conversion rates, surgical procedures, and outcomes. We additionally revised the literature and compared our results with 13 studies from the past 10 years.

RESULTS

There were 22 and 51 patients in the cholecystobiliary and bilioenteric groups, respectively. Our preoperative suspicion of a fistula was 80%. We started 88% of procedures by laparoscopic approach. The effectiveness of laparoscopy in the resolution of internal biliary fistula was 40% for cholecystobiliary fistula and 55% for bilioenteric fistulas. The most frequent cause for conversion to laparotomy was the difficulty to identify anatomical features, in addition to the need to perform a Roux en-Y hepaticojejunostomy. Choledocholithiasis was not associated with an increase in conversion rates.

CONCLUSIONS

Laparoscopic resolution of a biliary fistula is still a matter of controversy. Despite the high conversion rates, we believe that a great number of patients benefit from this minimally invasive technique. A high preoperative suspicion and trained surgeons are vital in the treatment of internal biliary fistulas.

Evaluation of the conversion rate as it relates to preoperative risk factors and surgeon experience: a retrospective study of 4013 patients undergoing elective laparoscopic cholecystectomy

Background

Our aim is to determine the relationships among patient demographics, patient history, surgical experience, and conversion rate (CR) during elective laparoscopic cholecystectomies (LCs).

Methods

We analyzed data from patients who underwent LC surgery between 2005 and 2014 based on patient charts and electronic documentation. CR (%) was evaluated in 4013 patients who underwent elective LC surgery. The relationships between certain predictive factors (patient demographics, endoscopic retrograde cholangiopancreatography (ERCP), acute cholecystitis (AC), abdominal surgery in the patient history, as well as surgical experience) and CR were examined by univariate analysis and logistic regression.

Results

In our sample (N = 4013), the CR was 4.2%. The CR was twice as frequent among males than among females (6.8 vs. 3.2%, p < 0.001), and the chance of conversion increased from 3.4 to 5.9% in patients older than 65 years. The detected CR was 8.8% in a group of patients who underwent previous ERCP (8.8 vs. 3.5%, p < 0.001). From the ERCP indications, most often, conversion was performed because of severe biliary tract obstruction (CR: 9.3%). LC had to be converted to open surgery after upper and lower abdominal surgeries in 18.8 and 4.8% cases, respectively. Both AC and ERCP in the patient history raised the CR (12.3%, p < 0.001 and 8.8%, p < 0.001). More surgical experience and high surgery volume were not associated with a lower CR prevalence.

Conclusions

Patient demographics (male gender and age > 65 years), previous ERCP, and upper abdominal surgery or history of AC affected the likelihood of conversion. More surgical experience and high surgery volume were not associated with a lower CR prevalence.

A novel high-performance CeO2-CuMn2O4 catalyst for toluene degradation

A series of spinel CuM₂O₄ (M = Mn, Fe, and Al) was used as the catalyst to investigate the effective degradation of toluene, and then CuMn₂O₄ with better catalytic activity was selected as the research object to study its activity at different ratios of Cu and Mn. Meanwhile, CeO₂ was introduced to modify CuMn bimetallic oxide to improve its catalytic performance. The structure, morphology, and valence states of surface elements of as-prepared catalysts were characterized by XRD, TEM, SEM, N₂ adsorption-desorption, XPS, and H₂-TPR. Using toluene as a probe molecule, the catalytic activity of the catalyst was tested and the results showed that the conversion rate of toluene catalyzed by CeO₂-CuMn₂O₄ catalyst can reach 90% at 200 °C (T₉₀) and 100% at 240 °C (T₁₀₀). The CO₂ yield can also reach 100% at 248 °C. Moreover, the possible catalytic mechanism for toluene by the CeO₂-CuMn₂O₄ was briefly explored. The catalytic oxidation of toluene over the oxide follows the Mars-van Krevelen mechanism.

Conversion rate of laparoscopic or robotic to open sacrocolpopexy: are there associated factors and complications?

OBJECTIVES

To evaluate the conversion rate of laparoscopic or robotic to open sacrocolpopexy and to identify associated factors in a large population-based database.

METHODS

We used Health Care Cost and Utilization Project-National Inpatient Sample (HCUP-NIS) databases 2005-2014. We extracted data on apical suspension and synthetic mesh with laparoscopy or robot in adult women using International Classification of Diseases, ninth edition, Clinical Modification (ICD-9-CM) codes. We evaluated the rate of conversion and used logistic regression to study the association with risk factors.

RESULTS

We identified 3295 women with laparoscopic or robotic sacrocolpopexies. There were 2777 robotic procedures with 37 conversion (1.33%) and 518 laparoscopic procedures with 37 conversions (7.14%), with an overall conversion rate of 2.2%. Median age was 62 years [interquartile range (IQR) = 55-69]. Concomitant hysterectomy was significantly more frequent in the robotic than laparascopic group (41.7% versus 13.9%, p < 0.01) and was not associated with conversion. Factors associated with lower conversion included a robotic approach (adjusted odd ratio (aOR) 0.32 [95% CI 0.19-0.54]) and private insurance (aOR 0.53 [95% CI 0.32-0.86]). Factors associated with higher conversion were obesity (aOR 3.27 [95% CI 1.72-6.19]) and lysis of adhesions (aOR 3.32 [95% CI 1.89-5.85]). Accidental organ puncture was significantly associated with conversion (14.9% versus 3.8%; p < 0.01).

CONCLUSION

In this American database, the rate of conversion of laparoscopic or robotic to open sacrocolpopexy was low. The majority (84%) of minimally invasive sacrocolpopexies used a robotic approach, which was associated with a lower risk of conversion. Obesity and lysis of adhesions were associated with a higher risk of conversion.

Pretreatment clamping of pulmonary artery during uniportal thoracoscopic lobectomy

Background

Intraoperative pulmonary artery (PA) hemorrhage is one of the leading reasons for conversion from uniportal VATS to open thoracotomy, especially for the small incision (≤3 cm) uniportal VATS performed by our department. So, We designed a technology called pretreatment clamping of the pulmonary artery, which may be helpful to solve the problem.

Methods

A retrospective analysis of 19 patients who had pulmonary artery bleeding during uniportal thoracoscopic lobectomy in which one group had undergone preventive pulmonary artery clamping, the clamping group (n = 11), and one group which did not receive preventive clamping, the non-clamping group (n = 8). We compared the rates of conversion from the uniportal VATS approach to open thoracotomy or multi-incision operation, duration of pulmonary artery repair, blood loss, length of postoperative hospital stay and postoperative complications of the two groups.

Results

Compared to the non-clamping group, the clamping group had lower rates of conversion to open thoracotomy (0% vs 62.5%, p < 0.05) and lower rates of conversion to multi-incision operations (18.2% of non-clamping converted to 2-port approach vs 12.5% of clamping converted to 2-port approach and 12.5% converted to 3-port approach, p < 0.05). Duration of pulmonary artery repair was reduced in the clamping group (10.1 ± 3.2 min vs 18.3 ± 5.5 min, p < 0.05). The clamping group also had decreased blood loss (23.6 ± 11.2 ml vs 47.5 ± 14.9 ml, p<0.05). There were no significant differences in postoperative hospital stay and postoperative complications between the two groups.

Conclusion

Pretreatment clamping of the pulmonary artery in VATS lobectomy can decrease conversion rates, decrease blood loss, shorten repairing time of the pulmonary artery, and feasibly can be applied in uniportal thoracoscopic lobectomy.

[Value of laparoscopy in blunt and penetrating abdominal trauma-a systematic review]

BACKGROUND

The range of indications for laparoscopic procedures has been continuously widened in recent years. At the same time, however, the diagnostic and therapeutic role of laparoscopy in the management of blunt and penetrating abdominal trauma remains controversial.

METHODS

A systematic literature search was carried out in PubMed from 2008 to 2019 on the use of laparoscopy in blunt and penetrating abdominal trauma. Studies were analyzed in terms of relevant operative and perioperative event rates (rate of missed injuries, conversion rate, postoperative complication rate). On the basis of this analysis, an algorithm for the use of laparoscopy in abdominal trauma was developed for clinical practice.

RESULTS

A total of 15 full texts with 5869 patients were found. With a rate of 1.4%, laparoscopically missed injuries were very rare for both penetrating and blunt abdominal trauma. Of all trauma laparoscopies 29.3% were converted to open surgery (laparotomy). Among the non-converted laparoscopies 60.5% were therapeutic. Complications occurred after trauma laparoscopy in 8.6% of cases.

CONCLUSION

By means of systematic laparoscopic exploration, missed injuries in abdominal trauma are extremely rare, so that concerns in this respect no longer seem justified. A large proportion of intra-abdominal injuries can be treated using laparoscopy or laparoscopically assisted procedures.

Testing possible causes of gametocyte reduction in temporally out-of-synch malaria infections

BACKGROUND

The intraerythrocytic development cycle (IDC) of the rodent malaria Plasmodium chabaudi is coordinated with host circadian rhythms. When this coordination is disrupted, parasites suffer a 50% reduction in both asexual stages and sexual stage gametocytes over the acute phase of infection. Reduced gametocyte density may not simply follow from a loss of asexuals because investment into gametocytes ("conversion rate") is a plastic trait; furthermore, the densities of both asexuals and gametocytes are highly dynamic during infection. Hence, the reasons for the reduction of gametocytes in infections that are out-of-synch with host circadian rhythms remain unclear. Here, two explanations are tested: first, whether out-of-synch parasites reduce their conversion rate to prioritize asexual replication via reproductive restraint; second, whether out-of-synch gametocytes experience elevated clearance by the host's circadian immune responses.

METHODS

First, conversion rate data were analysed from a previous experiment comparing infections of P. chabaudi that were in-synch or 12 h out-of-synch with host circadian rhythms. Second, three new experiments examined whether the inflammatory cytokine TNF varies in its gametocytocidal efficacy according to host time-of-day and gametocyte age.

RESULTS

There was no evidence that parasites reduce conversion or that their gametocytes become more vulnerable to TNF when out-of-synch with host circadian rhythms.

CONCLUSIONS

The factors causing the reduction of gametocytes in out-of-synch infections remain mysterious. Candidates for future investigation include alternative rhythmic factors involved in innate immune responses and the rhythmicity in essential resources required for gametocyte development. Explaining why it matters for gametocytes to be synchronized to host circadian rhythms might suggest novel approaches to blocking transmission.

Reproducibility of the T-SPOT.TB test for screening Mycobacterium tuberculosis infection in Japan

OBJECTIVES

The interferon-gamma release assay (IGRA) is useful for diagnosing Mycobacterium tuberculosis infections, especially in countries where Bacille Calmette-Guérin vaccinations are performed. However, reproducibility of the IGRA is unclear, as recent data suggest high IGRA conversion and reversion rates in serial tests among healthcare workers. This longitudinal study aimed to evaluate reproducibility of T-SPOT.TB for screening M. tuberculosis infections in Japan.

METHODS

Results of T-SPOT.TB tests performed between April 2014 and March 2016 at two hospitals in Yokohama, Japan, where the incidence of tuberculosis was 18.0 per 100,000 population in 2014, were analyzed.

RESULTS

In total, 3890 T-SPOT.TB tests were included. Overall, positive and negative test rates were 8.4% and 87.6%, respectively. Among 373 serial tests within two years, conversion and reversion rates were only 1.1% and 12.5%, respectively. Almost all patients who were initially negative (98.9%) remained so. There was no statistically significant difference between the outcomes observed at the two hospitals.

CONCLUSIONS

The conversion rate of T-SPOT.TB in Japan is as low as that recently reported in other countries where the incidence of tuberculosis is low. These data indicate that T-SPOT.TB is a reproducible tuberculosis screening tool at local hospitals in areas with a moderate incidence of tuberculosis.

Comparison of Robotic and Laparoscopic Hysterectomy for the Large Uterus

Background and Objectives:

We compared the outcome of robotic hysterectomy (RH) with laparoscopic hysterectomy (LH) for large uteri (≥16 weeks).

Methods:

This was a retrospective review over 5 years of 165 women (RH, 46; LH, 119). Demographic data, conversion, hemoglobin drop, indication, operating time, postoperative stay, and intra-operative strategies (adhesiolysis, myomectomy) were recorded.

Results:

Mean age was 45.7 ± 6.4 years and 44.5 ± 5.4 years (no diff) and body mass index was 30.2 ± 6.3 kg/m² and 27.8 ± 4.8 kg/m² (P = .009) in the RH and LH groups. There was no difference in percentage of women with previous laparotomy (RH, 15.2% vs LH, 13.4%) and mean number of lower-segment caesarean section (RH, 1.0 vs LH, 0.8). Mean size of uterus was similar (RH, 20.0 weeks vs LH, 17.4 weeks). The mean number of ports was higher in the RH group (RH, 4.2 vs LH, 3.4; P < .001) as was needed for adhesiolysis (RH, 71.7% vs LH, 35.3%; P < .001). Difficult bladder dissection was more in the RH group (56.5% vs 26.1%; P < .001). Vaginal morcellation was similar in both groups (RH, 89.1%; LH, 83.2%). RH took longer operating time (131.0 vs 110.6 minutes; P = .006). RH had less drop in Hb (1.0 vs 1.8 g/dL; P < .001) and remained the same after multiple regression analysis. Postoperative stay was similar in both groups (1.4 days). Requirement of intravenous analgesia was significantly lower in the RH group (12.5 vs 30.9 hours; P < .001). Open conversion rate was 4.3% (RH) and 10.9% (LH) but not significant.

Conclusion:

A higher body mass index, more adhesiolysis, and difficult bladder dissection imply a more challenging nature of women who underwent RH. Despite this, RH was shown to be feasible and safe with a lower blood loss.

Single-Incision Laparoscopic Appendectomy in Children And Conversion to Multiport Appendectomy

BACKGROUND

Single-incision laparoscopic appendectomy (SILA) in the pediatric population has been well described. Our children's hospital has adopted this modality for nearly all appendectomies. From our center's experience, we hoped to identify factors that portend conversion from SILA to multiport appendectomy. We compared our cohort of conventional three-port laparoscopic appendectomy (CLA) for outcomes including operative time, postop length of stay (LOS), complications, and readmission.

MATERIALS AND METHODS

A retrospective chart review of patients who underwent appendectomy from 2012 to 2017 at our children's hospital was performed. The type of appendectomy performed, if the case required conversion to multiple ports, and perforation status were recorded. Demographic data identified included age, sex, and body mass index. Outcomes analyzed were operative time, LOS, and postoperative complication/readmission rate.

RESULTS

Of 1001 appendectomies performed, 959 (95.9%) were initiated with plan for SILA, and 35 (3.5%) were initiated CLA. Of those initiated SILA, 884/959 (92.2%) were completed without additional port placement. Cases which were not able to be completed SILA were statistically significantly more likely to be male patients, have increased body mass index, or perforated appendicitis. When compared to cases initiated CLA, SILA remained statistically similar for readmission and LOS but had significantly faster operative time.

CONCLUSIONS

SILA appears to be a safe and efficient modality for the treatment of appendicitis in pediatric populations with no increased morbidity. Parents of children who are obese, males, or present with perforation should be counseled regarding the possibility of additional port placement or considered for initiating conventional three-port laparoscopic appendectomy.

Surgical volume and conversion rate in laparoscopic hysterectomy: does volume matter? A multicenter retrospective cohort study

Background

A multicenter, retrospective, cohort study was conducted in the Netherlands. The aim was to evaluate whether surgical volume of laparoscopic hysterectomies (LHs) performed by proven skilled gynecologists had an impact on the conversion rate from laparoscopy to laparotomy.

Methods

In 14 hospitals, all LHs performed by 19 proven skilled gynecologists between 2007 and 2010 were included in the analysis. Surgical volume, conversion rate and type of conversion (reactive or strategic) were retrospectively assessed. To estimate the impact of surgical volume on the conversion rate, logistic regressions were performed. These regressions were adjusted for patient’s age, Body Mass Index (BMI), ASA classification, previous abdominal surgery and the indication (malignant versus benign) for the LH.

Results

During the study period, 19 proven skilled gynecologists performed a total of 1051 LHs. Forty percent of the gynecologists performed over 20 LHs per year (median 17.3, range 5.4–49.5). Conversion to laparotomy occurred in 5.0% of all LHs (53 of 1051); 38 (3.6%) were strategic and 15 (1.4%) were reactive conversions. Performing over 20 LHs per year was significantly associated with a lower overall conversion rate (OR_adjusted 0.43, 95% CI 0.24–0.77), a lower strategic conversion rate (OR_adjusted 0.32, 95% CI 0.16–0.65), but not with a lower reactive conversion rate (OR_adjusted 0.96, 95% CI 0.33–2.79).

Conclusion

A higher annual surgical volume of LHs by proven skilled gynecologists is inversely related to the conversion rate to laparotomy, and results in a lower strategic conversion rate.

Contributions of vehicular emissions and secondary formation to nitrous acid concentrations in ambient urban air in Tokyo in the winter

Nitrous acid (HONO) plays an important role in the formation of OH radicals, which are involved in photochemical oxidation. HONO concentrations in ambient air at urban sites have previously been measured, but very few studies have been performed in central Tokyo. In this study, HONO concentrations in ambient air in southeast central Tokyo (near Tokyo Bay) in winter were determined by incoherent cavity enhanced absorption spectroscopy. The O₃, NO, NO₂, and SO₂ concentrations were simultaneously determined. The NO concentrations were used to classify the parts of the study period into types I (high pollution), II (medium pollution), and III (low pollution). The maximum HONO concentrations in the type I, II, and III periods were 7.1, 4.5, and 3.0ppbv, respectively. These concentrations were comparable to concentrations previously found in other Asian megacities. The mean HONO concentration varied diurnally, and HONO was depleted between 00:00 and 03:00 each day. The sampling site is surrounded by roads with high traffic loads, but vehicular emissions were estimated to contribute <10% of the HONO concentrations. Two positive and negative relative humidity dependences of the HONO to NO₂ ratio were confirmed, implying the existence of the two different secondary formation process of HONO. The NO₂ to HONO conversion rates at night in the type I, II, and III periods were 6.3×10^-3, 7.6×10^-3, and 4.2×10^-3h^-1, respectively.

Phosphoenolpyruvate:glucose phosphotransferase system modification increases the conversion rate during L-tryptophan production in Escherichia coli

Escherichia coli FB-04(pta1), a recombinant L-tryptophan production strain, was constructed in our laboratory. However, the conversion rate (L-tryptophan yield per glucose) of this strain is somewhat low. In this study, additional genes have been deleted in an effort to increase the conversion rate of E. coli FB-04(pta1). Initially, the pykF gene, which encodes pyruvate kinase I (PYKI), was inactivated to increase the accumulation of phosphoenolpyruvate, a key L-tryptophan precursor. The resulting strain, E. coli FB-04(pta1)ΔpykF, showed a slightly higher L-tryptophan yield and a higher conversion rate in fermentation processes. To further improve the conversion rate, the phosphoenolpyruvate:glucose phosphotransferase system (PTS) was disrupted by deleting the ptsH gene, which encodes the phosphocarrier protein (HPr). The levels of biomass, L-tryptophan yield, and conversion rate of this strain, E. coli FB-04(pta1)ΔpykF/ptsH, were especially low during fed-batch fermentation process, even though it achieved a significant increase in conversion rate during shake-flask fermentation. To resolve this issue, four HPr mutations (N12S, N12A, S46A, and S46N) were introduced into the genomic background of E. coli FB-04(pta1)ΔpykF/ptsH, respectively. Among them, the strain harboring the N12S mutation (E. coli FB-04(pta1)ΔpykF-ptsHN12S) showed a prominently increased conversion rate of 0.178 g g^-1 during fed-batch fermentation; an increase of 38.0% compared with parent strain E. coli FB-04(pta1). Thus, mutation of the genomic of ptsH gene provided an alternative method to weaken the PTS and improve the efficiency of carbon source utilization.

Irreversible Total Loss of Brain Function and Organ Donation in Patients with Aneurysmal Subarachnoid Hemorrhage

OBJECTIVE

Aneurysmal subarachnoid hemorrhage (aSAH) is a life-threatening disease with an often fatal clinical course leading to irreversible loss of brain function (ILBF) (i.e., brain death). The purpose of this study was to assess the prevalence and characteristics of patients with aSAH who became organ donors after diagnosis of ILBF.

METHODS

Anonymized clinical data sets of 395 patients treated for aSAH at a university medical center from January 2011 to December 2016 were retrospectively analyzed. Prevalence of consent for organ donation and clinical characteristics, including parameters for diagnosis of irreversible loss of brain function, were assessed.

RESULTS

After initial admission to the intensive care unit, 18.0% of patients (n = 71) died (Glasgow Outcome Scale score 1). Intracerebral hemorrhage occurred in 42.3% of patients who died, aneurysmal rebleeding occurred in 19.7%, and intraventricular hemorrhage occurred in 87.3%. In 50.7% of patients who died (n = 36), ILBF was diagnosed, and 32.4% (n = 23) of these patients became organ donors. In 55.6%, additional diagnostic electroencephalography was performed. Male patients significantly more often became organ donors than female patients (P = 0.008). ILBF with subsequent organ donation was predominantly seen in patients <60 years old. A total 85 of organs were explanted for donation, including 42 kidneys, 21 livers, 3 pancreas, 11 hearts and 8 lungs.

CONCLUSIONS

ILBF in the setting of fatal aSAH is a prevalent diagnosis with complex demands for neurointensive care physicians. We demonstrated the clinical characteristics and epidemiologic factors of patients with aSAH converting to organ donors.

Prevalence and conversion to dementia of Mild Cognitive Impairment in an elderly Italian population

BACKGROUND

Mild Cognitive Impairment (MCI) represents a significant risk factor for dementia but there are only a few Italian population studies on its prevalence and its rate of conversion to dementia.

AIMS

Aim of this study was to assess the prevalence of MCI, its subtypes, and rates of conversion to dementia 1 year later in an elderly Italian population.

METHODS

The data are based on an Italian multicenter population-based cohort study with both cross-sectional and longitudinal components. Two thousand three hundred thirty-seven individuals over 65 underwent screening, clinical confirmation and 1-year follow-up.

RESULTS

The prevalence of MCI was 21.6% and the amnestic multiple domain was the most frequent subtype (63.2%). The conversion rate to dementia was 4.1% and was found only in the amnestic multiple domain and in the unclassifiable subjects, persons with cognitive deficit but neither demented nor with MCI.

DISCUSSION

The prevalence of MCI in this population sample was similar to that found in other population studies using Petersen's modified MCI criteria as well as his original criteria. With regard to conversion to dementia, our results emphasize the importance to better classify the unclassifiable subjects at high risk of progression to dementia and also at risk of being undiagnosed and untreated.

CONCLUSION

MCI is characterized by extreme variability and instability. Data on the prevalence and the rate of conversion from MCI to dementia are difficult to compare given the important differences from study to study especially with regard to the diagnostic criteria utilized and their operationalization.

Hospital characteristics associated with increased conversion rates among organ donors in New England

BACKGROUND

It is unknown whether hospital characteristics affect institutional performance with regard to organ donation. We sought to determine which hospital- and patient-level characteristics are associated with high organ donor conversion rates after brain death (DBD).

METHODS

Data were extracted from the regional Organ Procurement Organization (2011-2014) and other sources. Hospitals were stratified into high-conversion hospitals (HCH; upper-tertile) and low-conversion hospitals (LCH; lower-tertile) according to conversion rates. Hospital- and patient-characteristics were compared between groups.

RESULTS

There were 564 potential DBD donors in 27 hospitals. Conversion rates differed between hospitals in different states (p < 0.001). HCH were more likely to be small (median bed size 194 vs. 337; p = 0.024), non-teaching hospitals (40% vs. 88%; p = 0.025), non-trauma center (30% vs. 77%; p = 0.040). Potential donors differed between HCH and LCH in race (p < 0.01) and mechanism of injury/disease process (p < 0.01).

CONCLUSION

There is significant variation between hospitals in terms of organ donor conversion rates. This suggests that there is a pool of potential donors in large specialized hospitals that are not successfully converted to DBD.

The impact of body mass index on short-term surgical outcomes after laparoscopic hepatectomy, a retrospective study

Background

Surgeons may expect technical difficulties and worse outcomes when performing laparoscopic hepatectomy (LH) on obese patients. The aim of this study is to assess the impact of body mass index (BMI) on short-term surgical outcomes and to verify risk factors of conversion rate and complications of LH.

Methods

Data were collected from 551 patients who underwent attempted LH between August 1998 and April 2013. Patients were classified into four groups depending on their BMI according to the WHO’s definition of obesity for Asia-Pacific region: underweight <18.5 kg/m² (Group1); normal 18.5–23.9 kg/m² (Group2); overweight 24–27.9 kg/m² (Group3); obese ≥ 28 kg/m² (Group4) respectively. Short-term surgical outcomes were compared across the BMI categories. Possible risk factors concerned conversion rate and complications were analyzed.

Results

The overall conversion rate of the 551 patients was 13.07 %. Conversion rate for Group 1, 2, 3, and 4 were 14.3 % (n = 5), 11.2 % (n = 38), 13.0 % (n = 19), and 34.5 % (n = 10) respectively. Patients within the obese group had a much higher conversion rate. The overall complications rate was 11.98 %, where the complication for Group 1, 2, 3, and 4 were 22.9 % (n = 8), 12.7 % (n = 43), 18.2 % (n = 12), and 10.3 % (n = 3) respectively. Patients within the underweight group had a higher complication rate, but it did not reach statistic difference. Obesity and surgical site of left lobe were independent risk factors of conversion. Age, abdominal surgery history, and type of left and right lobe resection were independent risk factors for complications.

Conclusions

In China, obesity increases risk of conversion rate but it dose not affect surgical complications and other short-outcomes after LH.

Electronic supplementary material

The online version of this article (doi:10.1186/s12871-016-0194-1) contains supplementary material, which is available to authorized users.

Enhanced conversion of induced neuronal cells (iN cells) from human fibroblasts: Utility in uncovering cellular deficits in mental illness-associated chromosomal abnormalities

The novel technology of induced neuronal cells (iN cells) is promising for translational neuroscience, as it allows the conversion of human fibroblasts into cells with postmitotic neuronal traits. However, a major technical barrier is the low conversion rate. To overcome this problem, we optimized the conversion media. Using our improved formulation, we studied how major mental illness-associated chromosomal abnormalities may impact the characteristics of iN cells. We demonstrated that our new iN cell culture protocol enabled us to obtain more precise measurement of neuronal cellular phenotypes than previous iN cell methods. Thus, this iN cell culture provides a platform to efficiently obtain possible cellular phenotypes caused by genetic differences, which can be more thoroughly studied in research using other human cell models such as induced pluripotent stem cells.

Vermicomposting as manure management strategy for urban small-holder animal farms - Kampala case study

Inadequate organic waste management can contribute to the spread of diseases and have negative impacts on the environment. Vermicomposting organic waste could have dual beneficial effects by generating an economically viable animal feed protein in the form of worm biomass, while alleviating the negative effects of poor organic waste management. In this study, a low-maintenance vermicomposting system was evaluated as manure and food waste management system for small-holder farmers. A vermicomposting system using the earthworm species Eudrilus eugeniae and treating cow manure and food waste was set up in Kampala, Uganda, and monitored for 172days. The material degradation and protein production rates were evaluated after 63days and at the end of the experiment. The material reduction was 45.9% and the waste-to-biomass conversion rate was 3.5% in the vermicomposting process on a total solids basis. A possible increase in the conversion rate could be achieved by increasing the frequency of worm harvesting. Vermicomposting was found to be a viable manure management method in small-scale urban animal agriculture; the return of investment was calculated to be 280% for treating the manure of a 450kg cow. The vermicompost was not sanitised, although hygiene quality could be improved by introducing a post-stabilisation step in which no fresh material is added. The value of the animal feed protein generated in the process can act as an incentive to improve current manure management strategies.

Laparoscopic Hysterectomies: Our 10 Years Experience in a Single Laparoscopic Center

STUDY OBJECTIVE

To evaluate the association between outcomes of laparoscopic hysterectomy with respect to clinical factors, intraoperative variants, and post-operative complications.

DESIGN

The study conducted was retrospective (Canadian Task Force Classification II-1).

SETTING

The set used in this study was a gynecological laparoscopic centre.

PATIENTS

The present study included 858 women who underwent laparoscopic hysterectomies with or without bilateral/unilateral salpingo-oophorectomy, from December 2004 to May 2014.

INTERVENTIONS

Eight hundred and sixteen patients underwent total laparoscopic hysterectomy, 14 patients underwent subtotal laparoscopic hysterectomy, 20 patients underwent laparoscopic-assisted vaginal hysterectomy, and 8 patients underwent laparoscopic radical hysterectomy with bilateral pelvic lymph node dissection.

MEASUREMENTS AND MAIN RESULTS

All surgeries were performed by the same surgeon, using the same surgical technique. The medical records were reviewed, and data were collected with respect to age, indications, type of surgery performed, intraoperative variants, and post-operative complications. Patient average age was 44.9 ± 6.2 years. Most common indication for benign TLH was leiomyoma of 54.4 %. Indications for laparoscopic radical hysterectomy were early stage endometrial cancer (n = 5) and early stage cervical cancer (n = 3). The maximum uterine size operated on was from 20-26 weeks, 4.9 % (n = 42). 9.7 % had previous abdominopelvic surgery. Fifty three % underwent unilateral/bilateral salpingo-oophorectomy. Conversion rate was 0.93 % (n = 8). The minimum and maximum operating time during the total study period was 20 min-2 h. The major complication rates were 0.9 % (n = 8). The hospital stay was not more than 2 days.

CONCLUSION

In our experience of 858 laparoscopic hysterectomies, 850 were done for benign indications, and 8 done for malignancies. TLH can be performed more safely and under vision, with less blood loss, early post-operative recovery, less post-operative infection, and less complication rate.

Conversion from radiologically isolated syndrome to multiple sclerosis

BACKGROUND

The aim of this study was to estimate the conversion rate from radiologically isolated syndrome (RIS) to definite multiple sclerosis (MS).

METHODS

During a mean (standard deviation [SD]) follow-up period of 17.4 (5.4) (range 8-29) months, 25 subjects with RIS and without neurological symptom aged 22-45 year from a single-center have been examined for the occurrence of definite MS. The mean (SD) age of participants was 35.1 (6.2) years at first brain magnetic resonance imaging (MRI). The definite MS were assessed using the revised McDonald's criteria (2010).

RESULTS

Six of 25 patients developed clinical symptom consistent with criteria for definite MS. The conversion rate from RIS to definite MS was 1.5 (95% confidence interval [CI] 0.54, 3.17) per 100 person-months based on 480 person-months of follow-up. Multivariate analysis revealed that presence of contrast-enhancing lesions on the initial MRI was marginally significantly associated with MS (hazard ratio 1.83, 95% CI 0.98, 3.45, P = 0.060).

CONCLUSIONS

This is the first estimate of conversion rate from RIS to definite MS in Iran. The conversion rates from RIS to definite MS in these participants are high and intensive follow-up and intervention strategies are recommended for these high-risk individuals. A larger study is warranted to assess this risk in greater detail.

The HAC trial (harmonic for acute cholecystitis): a randomized, double-blind, controlled trial comparing the use of harmonic scalpel to monopolar diathermy for laparoscopic cholecystectomy in cases of acute cholecystitis

BACKGROUND

The HARMONIC SCALPEL (H) is an advanced ultrasonic cutting and coagulating surgical device with important clinical advantages, such as: reduced ligature demand; greater precision due to minimal lateral thermal tissue damage; minimal smoke production; absence of electric corrents running through the patient. However, there are no prospective RCTs demonstrating the advantages of H compared to the conventional monopolar diathermy (MD) during laparoscopic cholecystectomy (LC) in cases of acute cholecystitis (AC).

METHODS

This study was a prospective, single-center, randomized trial (Trial Registration Number: NCT00746850) designed to investigate whether the use of H can reduce the incidence of intra-operative conversion during LC in cases of AC, compared to the use of MD. Patients were divided into two groups: both groups underwent early LC, within 72 hours of diagnosis, using H and MD respectively (H = experimental/study group, MD = control group). The study was designed and conducted in accordance with the regulations of Good Clinical Practice.

RESULTS

42 patients were randomly assigned the use of H (21 patients) or MD (21 patients) during LC. The two groups were comparable in terms of basic patient characteristics. Mean operating time in the H group was 101.3 minutes compared to 106.4 minutes in the control group (p=ns); overall blood loss was significantly lower in the H group. Conversion rate was 4.7% for the H group, which was significantly lower than the 33% conversion rate for the control group (p<0.05). Post-operative morbidity rates differed slightly: 19% and 23% in the H and control groups, respectively (p=ns). Average post-operative hospitalization lasted 5.2 days in the H group compared to 5.4 days in the control group (p=ns).

CONCLUSIONS

The use of H appears to correlate with reduced rates of laparoscopic-open conversion. Given this evidence, H may be more suitable than MD for technically demanding cases of AC.

Sputum conversion at the end of 8weeks among category 1 tuberculosis patients: How reliable are the peripheral laboratory results?

OBJECTIVE

To assess the quality of week 8 sputum smear AFB microscopy performed by peripheral TB laboratories in Nigeria.

METHOD

A cross-sectional review was performed of all week 8 tuberculosis sputum smear slides reported for the first quarter of 2009 by peripheral laboratories in five States of Nigeria. Each slide was reviewed by two independent external slide readers as external quality check and also crosschecked with fluorescent microscopy.

RESULTS

In Akwa Ibom, Anambra, Enugu, Kogi and Ogun States, a total of 415, 315, 231, 206 and 428week 8 slides respectively were studied (a grand total of 1595 slides studied). The wide range of conversion rates between the different States as reported by peripheral labs (83.8% in Anambra State to 98.1% in Kogi State) was also observed by the external quality check (68.4% in Kogi State to 88.0% in Akwa Ibom State). In all the States, the studied sputum conversion rates reported by the peripheral labs were significantly higher than values obtained from external quality check and fluorescent microscopy (P=0.000).

CONCLUSION/RECOMMENDATION

There is a wide range of sputum conversion rates between States, but the conversion rate in each State is significantly higher than those of external quality check possibly indicating many false negative reports by peripheral labs. It is recommended that training and re-training of laboratory persons be continued. Internal and external quality checks should also continue to be practiced in the national TB program.

A national survey of spinal cord stimulation trial-to-permanent conversion rates

OBJECTIVES

Conversion rates from trial leads to permanent spinal cord stimulation (SCS) systems have recently come under scrutiny. Our goal was to examine the rate of conversion from trial lead to permanent system placement as well as identify factors associated with successful SCS conversion.

MATERIALS AND METHODS

We designed a large retrospective analysis using the Thomson Reuters MarketScan database. We included all patients who underwent a percutaneous trial of neurostimulatory electrodes from the years 2000 to 2009 who were aged 18 and older. Patients were then tracked to see if they went on to receive a permanent SCS system. Patients were also analyzed in univariate and multivariate models to identify factors associated with successful conversion.

RESULTS

A total of 21,672 unique instances of percutaneous trials were identified. Overall, 41.4% of those receiving trials went on to have a permanent SCS system installed within the subsequent three months. Factors associated with increased likelihood of successful conversion included having commercial insurance (43% vs. 37%, p < 0.0001), younger age (43% for those aged 35-44 vs. 39% for those aged 65 and older, p < 0.0001), and never having had a previous percutaneous trial attempt (44% for first-time trials vs. 27% for those on their second trial vs. 14% for those on their third or later trial, p < 0.0001). In multivariate analysis, we found significant variation in conversion rate by geographic area (patients in the North Central region vs. Northeast region: odds ratio 1.48, 95% confidence interval [1.31, 1.66]; p < 0.0001).

CONCLUSIONS

In this study of a national cohort of patients, we identified specific factors associated with higher conversion rates, along with significant geographical variation. In general, there is a need for better patient selection by physicians who practice neuromodulation.

Autonomic dysreflexia: a possible trigger for the development of heterotopic ossifications after traumatic spinal cord injury? : A clinical longitudinal study

PURPOSE

The aim of this study was to investigate the influence of the initial American Spinal Injury Association Impairment Scale (AIS) category and the conversion rate in acute traumatic tetraplegic patients on the development of heterotopic ossifications (HO). The second objective was to prove the hypothesis that tetraplegic patients with autonomic dysreflexia (AD) develop HO more often than patients without AD.

METHODS

A retrospective analysis from 2002 to 2009 of 330 patients with spinal cord injuries was performed and led to the inclusion of 77 traumatic tetraplegic patients. Clinical data was reviewed to determine the appearance of HO (n = 8) and its possible coincidence with AD during urodynamics. Spearman's correlation coefficient was calculated to test the relationship between HO and initial AIS category or the change in AIS category within 6 weeks. A matched pair (age, neurological level of injury) analysis of two samples (n = 8 with/without appearance of HO; total n = 16) was performed.

RESULTS

The appearance of HO was significantly correlated with an initial AIS A compared to incomplete tetraplegia at baseline (p < 0.017). The conversion of AIS A into incomplete tetraplegia was highly correlated with the incidence of HO (p < 0.003). AD showed a positive correlation with HO (r = 0.97, p = 0.001).

CONCLUSIONS

An initial AIS A that converts early into an incomplete tetraplegia constitutes a risk factor for the development of HO. Additionally, AD constitutes an important trigger in the development of HO in acute traumatic tetraplegic patients.