Perioperative outcomes of laparoscopic low anterior resection using ArtiSential® versus robotic approach in patients with rectal cancer: a propensity score matching analysis

BACKGROUND

Total mesorectal excision using conventional straight fixed devices may be technically difficult because of the narrow and concave pelvis. Several laparoscopic articulating tools have been introduced as an alternative to robotic systems. The aim of this study was to compare perioperative outcomes between laparoscopic low anterior resection using ArtiSential® and robot-assisted surgery for rectal cancer.

METHODS

This retrospective study included 682 patients who underwent laparoscopic or robotic low anterior resection  for rectal cancer from September 2018 to December 2021. Among them, 82 underwent laparoscopic surgery using ArtiSential® (group A) and 201 underwent robotic surgery (group B). A total of 73 [group A; 66.37 ± 11.62; group B 65.79 ± 11.34] patients were selected for each group using a propensity score matching analysis.

RESULTS

There was no significant difference in the baseline characteristics between group A and B. Mean operative time was longer in group B than A (163.5 ± 61.9 vs 250.1 ± 77.6 min, p < 0.001). Mean length of hospital stay was not significantly different between the two groups (6.2 ± 4.7 vs 6.7 ± 6.1 days, p = 0.617). Postoperative complications, reoperation, and readmission within 30 days after surgery were similar between the two groups. Pathological findings revealed that the circumferential resection margins were above 10 mm in both groups (11.00 ± 7.47 vs 10.17 ± 6.25 mm, p = 0.960). At least 12 lymph nodes were sufficiently harvested, with no significant difference in the number harvested between the groups (20.5 ± 9.9 vs 19.7 ± 7.3, p = 0.753).

CONCLUSIONS

Laparoscopic low anterior resection using ArtiSential® can achieve acceptable clinical and oncologic outcomes. ArtiSential®, a multi-joint and articulating device, may serve a feasible alternative approach to robotic surgery in rectal cancer.

Total intravenous anesthesia without muscle relaxant for pulmonary wedge resection in a patient with amyotrophic lateral sclerosis: a case report

Muscle relaxants may exacerbate the symptoms of amyotrophic lateral sclerosis (ALS). Furthermore, ALS patients often experience respiratory muscle weakness. Herein, we report the case of a 63-year-old man with ALS who underwent pulmonary wedge resection using total intravenous anesthesia without muscle relaxant and single lumen endotracheal tube. After an unremarkable surgical procedure, the patient was transferred to the intensive care unit after extubation. The patient did not experience any worsening of ALS symptoms over the one-year follow-up period. Our experience shows that total intravenous anesthesia without muscle relaxants can be used as an anesthetic method for lung surgery in ALS patients. We report this case along with a brief literature review.

Preparation of amine-functionalized lignins for the selective adsorption of Methylene blue and Congo red

Research on low-cost bio-adsorbents for the removal of harmful substances from effluents has recently attracted significant attention. In this study, three types of amino-silane-modified lignins (ASLs) with primary, secondary, and tertiary amine groups were prepared, and their adsorption behavior toward cationic and anionic dyes was investigated. Chemical structural analyses indicated that the three amino-silane reagents resulted in different molecular self-assembly structures on the lignin surface. The ASLs exhibited enhanced thermal stabilities and increased surface areas with different surface charges in different pH ranges. Owing to the high density of primary, secondary, and tertiary amine groups, the ASLs exhibited excellent adsorption capacities for cationic and anionic dyes. Additionally, they selectively adsorb anionic and cationic dyes according to the pH conditions. The ASL with primary amine had the highest adsorption capacity for Methylene blue and Congo red, reaching 187.27 and 293.26 mg·g^-1, respectively, followed by ASLs with the secondary amine and tertiary amine. All adsorption processes followed the Langmuir and Temkin isotherms and had pseudo-second-order kinetics. The hypothesized adsorption mechanism mainly involves electrostatic interaction, NH-π interaction, hydrogen bonding interaction and π-π interaction.

Synthesis of lignin-modified cellulose nanocrystals with antioxidant activity via Diels-Alder reaction and its application in carboxymethyl cellulose film

Multifunctional polymers derived from renewable organic substances have received significant attention. In this work, the Diels-Alder "click" reaction was used to synthesize a renewable copolymer with the mechanical strength of cellulose nanocrystals (CNCs) and the natural antioxidant activity of lignin. Chemical structural analysis and molecular weight results confirmed that lignin was successfully attached to the CNCs. Phenolic hydroxyl groups were introduced into CNCs, resulting in good antioxidant activity with an IC₅₀ value of 1.49 mg/mL, although a slight decrease in the crystallinity index and thermal properties was observed. Additionally, carboxymethyl cellulose (CMC) films containing lignin-modified CNCs were prepared by solution casting. The lignin-modified CNCs endowed film with antioxidant activity and also contributed to increasing the tensile strength by 70%. This indicated that the lignin-modified CNCs with good antioxidant activities and mechanical strength have promising applications in multifunctional materials.

The potential cytotoxic effects of urban particle matter on olfaction

BACKGROUND

Urban particulate matter (UPM) in ambient air is implicated in a variety of human health issues worldwide, however, few studies exist on the effect of UPM on the olfactory system. This study aimed to identify the factors affecting the destruction of the olfactory system in a mouse model following UPM exposure.

METHODS

Mice were divided into: control and four UPM-exposed groups (200 µg UPM at 1 and 2 weeks, and 400 µg UPM at 1 and 2 weeks [standard reference material 1649b; average particle diameter 10.5 μm]). The olfactory neuroepithelium was harvested for histologic examination, gene ontology, quantitative real-time polymerase chain reaction, and western blotting.

RESULTS

Compared to the control group, olfactory marker protein, Olfr1507, ADCY3, and GNAL mRNA levels were lower, and S-100, CNPase, NGFRAP1, BDNF, and TACR3 mRNA levels were higher in the olfactory neuroepithelium of the UPM groups. Moderately positive correlation was present between the 1- and 2-week groups. After analyzing the 200 and 400 UPM groups separately, the strength of the association between the 200 UPM 1- and 2-week groups was moderately positive. No differences was present in the neuroepithelial inflammatory marker levels between the UPM and control groups.

CONCLUSIONS

UPM could have cytotoxic effects on the olfactory epithelium. The exposure time and particular concentration of UPM exposure could affect the degree of destruction of the olfactory neuroepithelium. The olfactory regeneration mechanism could be related to the neurotrophic factors, olfactory ensheathing cell stimulation, and trigeminal nerve support.

A Novel Biosorbent From Hardwood Cellulose Nanofibrils Grafted With Poly(m-Aminobenzene Sulfonate) for Adsorption of Cr(VI)

Cellulose from different lignocellulosic biomass can be used to prepare various materials. In this work, the cellulose nanofibrils were produced from hardwood bleached kraft pulp. Then, a novel biosorbent from cellulose nanofibrils grafted with poly(m-aminobenzene sulfonate) (PABS) was prepared for effective detoxification and adsorption of Cr(VI) in an aqueous medium. 6,6-tetramethylpiperidine-1-oxyl (TEMPO)-oxidized cellulose nanofibrils (TOCNF) with a high aspect ratio was used as an adsorbent matrix. PABS, an amine-rich conductive polymer, was grafted onto TOCNF via a successive two-step reaction. The analyses of Fourier transform infrared (FT-IR) spectroscopy and X-ray photoelectron spectroscopy (XPS) confirmed the successful grafting reaction between TOCNF and PABS. The biosorbent from TOCNF-bonded PABS with the nitrogen content of 7.0% was synthesized. It exhibited excellent Cr(VI) adsorption capacity at a solution pH below 3, and almost 100% Cr(VI) can be removed. The adsorption of Cr(VI) on the biosorbent was described by a pseudo-second-order model and obeyed the Langmuir model. The Cr(VI) adsorption capacity of the biosorbent from TOCNF-bonded PABS was almost 10 times higher than that of TOCNF. It was interesting to note that part of Cr(VI) ions had been reduced to Cr(III) during the adsorption process. It indicated that the biosorbent from TOCNF grafted with PABS could detoxify and adsorb Cr(VI) synchronously.

Upregulation of DJ-1 expression in melanoma regulates PTEN/AKT pathway for cell survival and migration

Cutaneous melanoma is known to be one of the most dangerous skin cancers because of its metastatic functions. Today, it is essential to investigate specific biomarkers for the target treatment in many diseases including cancers. DJ-1 protein, also known as Parkinson disease 7, has various functions associated with cancer progression including cell survival and migration. Phosphatase and tensin homolog (PTEN) is a tumor suppressor that regulates the PI3K/AKT signaling pathway and its mutations have been reported to frequently occur in many cancers such as thyroid, breast and skin. Recently, DJ-1 has been identified as a negative regulator of PTEN in many human cancer cells. However, the impacts and relationship of DJ-1 and PTEN have not been studied yet in melanoma. To confirm the expression of DJ-1 and PTEN in melanoma compared to normal skin tissues and find out functions of DJ-1 in melanoma cells, Western blot analysis and immunohistochemical staining were used. Transfection of G361 cells with DJ-1-specific small interfering RNA was performed to figure out the roles of DJ-1 and the relationship between DJ-1 and PTEN in melanoma cells. In our study, the DJ-1 protein was significantly increased with loss of PTEN protein in melanoma compared to that in normal skin. Inhibition of DJ-1 in G361 cells induced apoptosis, and suppressed cell survival and migration. Furthermore, suppression of DJ-1 in G361 cells increased the expression of cleaved caspase-3, cleaved PARP, Bax, p53, and Daxx as well as PTEN, while it decreased expression of survivin, caspase-3, and PARP. Also, downregulated DJ-1 inhibited phosphorylation of AKT in G361 cells. Collectively, DJ-1 overexpression could affect the proliferative and invasive capabilities of melanoma cells via regulating the PTEN/AKT pathway and apoptosis-related proteins. This study suggests that DJ-1 may be a potential target for the treatment of melanoma.

Overexpression of Nrf2 promotes colon cancer progression via ERK and AKT signaling pathways

PURPOSE

We investigated the expression of Nrf2 in colorectal cancer and its correlation with clinicopathological characteristics as well as mechanisms and roles of Nrf2 expression including cell signaling pathway, survival, proliferation, and migration.

METHODS

Nrf2 expression was measured in 12 and 30 different colorectal cancer (CRC) tissues by western blot (WB) and immunohistochemistry (IHC), respectively. SW480 cells were used for cell proliferation and cell migration tests. The correlation between the expression of Nrf2 and clinicopathologic parameters were evaluated using the chi-square or Fisher exact test. Data are expressed as the mean ± standard deviation for 3 independent experiments. P < 0.05 was considered statistically significant.

RESULTS

Analysis of WB demonstrated that Nrf2 proteins were increased in CRC tissues, and decreased in normal tissues. IHC staining showed that the Nrf2 expression was elevated in CRC tissues, compared to matched normal tissues. When SW480 cells were suppressed with small interfering RNA of Nrf2, cell viability was inhibited, and cell apoptosis was increased. These results were found along with suppression of the phosphorylated form of extracellular signal-regulated kinase 1/2 and AKT.

CONCLUSION

This study suggests that overexpression of Nrf2 may be related to carcinogenesis and progression of CRC.

Multi-omic analysis of the effects of low frequency ventilation during cardiopulmonary bypass surgery

BACKGROUND

Heart surgery with cardio-pulmonary bypass (CPB) is associated with lung ischemia leading to injury and inflammation. It has been suggested this is a result of the lungs being kept deflated throughout the duration of CPB. Low frequency ventilation (LFV) during CPB has been proposed to reduce lung dysfunction.

METHODS

We used a semi-biased multi-omic approach to analyse lung biopsies taken before and after CPB from 37 patients undergoing coronary artery bypass surgery randomised to both lungs left collapsed or using LFV for the duration of CPB. We also examined inflammatory and oxidative stress markers from blood samples from the same patients.

RESULTS

30 genes were induced when the lungs were left collapsed and 80 by LFV. Post-surgery 26 genes were significantly higher in the LFV vs. lungs left collapsed, including genes associated with inflammation (e.g. IL6 and IL8) and hypoxia/ischemia (e.g. HIF1A, IER3 and FOS). Relatively few changes in protein levels were detected, perhaps reflecting the early time point or the importance of post-translational modifications. However, pathway analysis of proteomic data indicated that LFV was associated with increased "cellular component morphogenesis" and a decrease in "blood circulation". Lipidomic analysis did not identify any lipids significantly altered by either intervention.

DISCUSSION

Taken together these data indicate the keeping both lungs collapsed during CPB significantly induces lung damage, oxidative stress and inflammation. LFV during CPB increases these deleterious effects, potentially through prolonged surgery time, further decreasing blood flow to the lungs and enhancing hypoxia/ischemia.

Comparison of open and pneumovesical approaches for Politano-Leadbetter ureteric reimplantation: a single-center long-term follow-up study

PURPOSE

To report our experience with the laparoscopic pneumovesical approach for Politano-Leadbetter ureteric reimplantation and to compare the results to those obtained using a traditional open approach.

METHODS

We retrospectively reviewed the medical records of 52 patients who underwent Politano-Leadbetter ureteral reimplantation between 2012 and 2017. The peri-operative parameters, postoperative outcomes, and complication rates of patients who underwent the open approach for the Politano-Leadbetter procedure and those who underwent the laparoscopic pneumovesical approach were compared.

RESULTS

During the study period, 52 ureteric reimplantation procedures were analyzed. Among these, 28 and 24 patients underwent surgery using the open and pneumovesical approaches, respectively. The mean operative time did not differ between the groups (143.64 min vs. 128.12 min, P = 0.092). However, the pneumovesical group had a shorter duration of hospital stay (5.08 days vs 7.43 days, P = 0.001) and required less morphine analgesic for pain than did the open group (7.7% vs 32.1%, P = 0.027). No significant differences in the success rates (94.9% vs 92.5%, P = 0.512) or procedure-related complications were noted between the pneumovesical and open techniques.

CONCLUSIONS

The transvesicoscopic Politano-Leadbetter technique with pneumovesicum is safe and effective for ureteric reimplantation and is comparable to the open approach.

Platinum Supported Nitrogen-Doped Carbon Nanotubes/ZIF-8 Derived Carbon Composite Electrodes for a Methanol Oxidation

Pt-supported on ZIF-8 derived porous carbon (CZIF8) and nitrogen-doped multi-walled carbon nanotubes (NCNT) composites was prepared by pyrolysis process and chemical reduction. The electrochemical characterization and morphological analysis of composites was measured by cyclic voltammetry (CV), chronoamperometry, transmission electron microscope (TEM), and fourier transform infrared spectroscopy (FT-IR). These results indicate that the Pt-NCNT@CZIF8 nanocomposite showed electrochemically superior properties to methanol oxidation reaction and the higher electrochemical surface area (ECSA). Also, ZIF-8 derived carbon and modified the CNTs was thought to enhance the effective area of the platinum deposition site.

Characterization of solvent-fractionated lignins from woody biomass treated via supercritical water oxidation

Crude supercritical lignin (SCL) extracted from hardwood (Quercus mongolica) treated via supercritical water (SCW) oxidation was subjected to sequential fractionation with four organic solvents; five lignin fractions (F1-F4 and F_IN) were thus obtained. The molecular weight (MW) of the fractionated lignins gradually increased as fractionation proceeded. However, the content of methoxyl groups and phenolic hydroxyl groups tended to decrease with increasing molecular weight of the lignins. The functional groups of SCL and the fractionated lignins were very similar based on Fourier-transform infrared analysis. The syringyl/guaiacyl ratio (S/G ratio) of the fractionated lignins increased with an increase in the MW. The thermal stability decreased with decreasing MW of the fractionated lignins, and all fractions except for F1 had a maximum degradation temperature of around 360 °C. The glass transition temperature (T_g) of the fractions increased from 83 °C to 137 °C with increasing MW.

Minimum effective local anesthetic volume for surgical anesthesia by subparaneural, ultrasound-guided popliteal sciatic nerve block: A prospective dose-finding study

Because of its rapid onset time, recent years have seen an increase in the use of ultrasound (US)-guided popliteal sciatic nerve block (PSNB) via subparaneural injection for induction of surgical anesthesia. Moreover, in below-knee surgery, combined blocks, as opposed to sciatic nerve block alone, have become more common. These combined blocks often require a large volume of local anesthetic (LA), thus increasing the risk of local-anesthetic systemic toxicity (LAST). Thus, to decrease the risk of LAST, it is important to know the minimum effective volume (MEV) required for an adequate block. We, therefore, aimed to determine the MEV of ropivacaine 0.75% for induction of surgical anesthesia by the method of US-guided popliteal sciatic nerve block via subparaneural injection.Thirty patients underwent a US-guided PSNB with ropivacaine 0.75% at a 20-mL starting volume. Using a step-up/step-down method, we determined injection volumes for consecutive patients from the preceding patient's outcome. When an effective block was achieved within 40 minutes after injection, the next patient's volume was decreased by 2 mL. If the block failed, the next patient's volume was increased by 2 mL. The sensory and motor blockade was graded according to a 4-point scale. The block was considered a success if a combination of anesthesia and paresis (a score of 3 for both the sensory and motor nerves) was achieved within 40 minutes. The primary outcome measure was the MEV resulting in a successful subparaneural block of the sciatic nerve in 50% of patients (MEV50). Additionally, the data were processed with a probit regression analysis to determine the volume required to produce a complete sciatic nerve block in 90% of subjects (ED90).The MEV50 of 0.75% ropivacaine is 6.14 mL (95% confidence interval, 4.33-7.94 mL). The ED90 by probit analysis for a subparaneural injection was 8.9 mL (95% CI, 7.09-21.75 mL).The 6.14-mL MEV50 of ropivacaine 0.75% represents a 71% reduction in volume compared with neurostimulation techniques and a 14.7% reduction in volume compared with US-guided PSNB using the alternative perineural injection technique.

Assessment of pupillary light reflex using a smartphone application

In unconscious patients, pupillary light reflex is an indicator of brain damage. In the current study, a smartphone application was developed for the purpose of measuring pupillary light reflex with an aim to determine the agreement between pupillary light reflex measurements using a smartphone application (APP) and a penlight (PEN). The APP acquires five sequential photographs using the camera flash in order to stimulate the pupil. The initial image is captured prior to the flash, and the subsequent image is obtained while the flash is on. The remaining three images are captured whilst the flash is off. Pupillary right reflex was assessed in 30 healthy subjects using a PEN. After 10 min, the examiners inspected the images of light reflex acquired from the same subjects using the APP, and completed the corresponding questionnaire containing details of pupil size and degree of response. Agreement between the two assessment methods was determined by calculating bias, limits of agreement, and the intraclass correlation (ICC) coefficient. A statistically significant difference was not observed between the two methods regarding pupil size and degree of response. Bias was 0.1 mm and limits of agreement were ±1.5 mm, as compared with PEN. ICC was 0.93 (95% confidence interval, 0.89-0.96). Therefore, it may be concluded that the results of pupillary light reflex assessed by PEN and APP display no significant difference. Furthermore, the APP provides advantages such as portability, objectivity and the possibility of being used as objective medical evidence.

Initial experiences of laparoscopic intravesical detrusorraphy using the Politano-Leadbetter technique

INTRODUCTION

Minimally invasive laparoscopic surgical procedures are increasingly being used for the management of vesicoureteral reflux.

OBJECTIVE

We present our experience of the laparoscopic Politano-Leadbetter technique performed under pneumovesicum conditions, which allows an orthotopic ureteral location after vesicoureteral reflux correction. Our procedure recreates the new ureteric orifice in a normal anatomical position with potential less morbidity and better cosmesis.

STUDY DESIGN

Our series comprises ten cases. The three 5 mm ports were introduced through bladder wall under cystoscopic vision. A 5-0 monofilament traction suture was used and dissection was carried out. After the ureteral mobilization, the location of the new hiatus was selected in a straight line superior to the original orifice. Dissection of the submucosal tunnel was started from the new hiatus and advanced to the original hiatus and the ureter was gently drawn passed through the tunnel. The ureter was rolled up and muscle fibers were incised until ureter could freely move from the base of the new hiatus. Finally, after spatulation of the terminal part of the ureter, ureterovesical anastomosis was performed with intracorporeal suturing using 5-0 monofilament sutures.

RESULTS

The average operative time was 125 min, with an average of 93 min for unilateral and 133 min for bilateral reimplantation. Blood loss was minimal and drains were used selectively. Removal of urethral catheter was decided empirically after hematuria stopped. Mean catheterization time was 5.1 days. The mean postoperative hospital stay was 6.2 days.

DISCUSSION

This study had limitations: the small number of cases, follow-up period is relatively short and data on the pre-operative bladder capacity, catheter-related morbidity, pain control and cosmesis are lacking. But most cases showed positive clinical results including acceptable operating time and good resolution rate with minimal complication. Our Politano-Leadbetter transvesicoscopic ureteric reimplantation is safe and useful in the resolution of VUR, even though the laparoscopic ureteric reimplantation is technically demanding even for experienced pediatric surgeons. Considering the main advantages of endoscopic surgery, our new vesicoscopic technique could be an optional treatment to the open reimplantation and has merits because whole the procedure are performed within the bladder, so there is no risk of intraperitoneal organ injury.

CONCLUSION

Though the role of this new technique in the treatment of VUR remains to be determined, the technique could be an optional treatment to replace other surgical methods as a less invasive and effective therapeutic method.

Body composition is more closely related to the development of knee osteoarthritis in women than men: a cross-sectional study using the Fifth Korea National Health and Nutrition Examination Survey (KNHANES V-1, 2)

OBJECTIVE

To evaluate the association between knee osteoarthritis (OA) and body composition parameters, and to analyze the correlations of both obesity and lower extremity muscle mass with radiographic knee OA in relation to sex.

METHODS

This was a cross-sectional study using data on body composition parameters measured using dual energy X-ray absorptiometry in 4246 participants in the Fifth Korea National Health and Nutrition Examination Survey. The relationships between knee OA and body composition parameters were evaluated. The associations between knee OA and the four subgroups corresponding to obesity and muscle mass percentage in both lower extremities were analyzed separately for each sex.

RESULTS

The lower extremity muscle mass showed a decreasing trend, while fat parameters showed an increasing linear trend (P for trend <0.05) with increasing severity of knee OA in women. The odds ratio of each quarter percentile group (25 percentile) for fat parameters showed an increasing trend, while that of the lower extremity muscle mass showed a decreasing linear trend in relation to knee OA in women (P for trend < 0.05). In women, low percentage of lower extremity muscle mass was more associated with knee OA regardless of obesity (P < 0.05). However, there were no associations between all body composition parameters and knee OA in men.

CONCLUSION

In women, high fat mass and low lower extremity muscle mass were associated with presence and severity of knee OA. Lower extremity muscle mass was more closely correlated with knee OA than obesity in women.

The influence of surgical factors on dislocation of the meniscal bearing after Oxford medial unicompartmental knee replacement: a case-control study

The aim of this study was to evaluate the risk factors for dislocation of the bearing after a mobile-bearing Oxford medial unicompartmental knee replacement (UKR) and to test the hypothesis that surgical factors, as measured from post-operative radiographs, are associated with its dislocation From a total of 480 UKRs performed between 2001 and 2012, in 391 patients with a mean age of 66.5 years (45 to 82) (316 female, 75 male), we identified 17 UKRs where bearing dislocation occurred. The post-operative radiological measurements of the 17 UKRs and 51 matched controls were analysed using conditional logistic regression analysis. The post-operative radiological measurements included post-operative change in limb alignment, the position of the femoral and tibial components, the resection depth of the proximal tibia, and the femoral component-posterior condyle classification. We concluded that a post-operative decrease in the posterior tibial slope relative to the pre-operative value was the only significant determinant of dislocation of the bearing after medial Oxford UKR (odds ratio 1.881; 95% confidence interval 1.272 to 2.779). A post-operative posterior tibial slope < 8.45° and a difference between the pre-operative and post-operative posterior tibial slope of > 2.19° may increase the risk of dislocation.

Comparison of two dosing schedules of intravenous dexmedetomidine in elderly patients during spinal anesthesia

Background

As the number of elder patients grows, spinal anesthesia for such patients are increasing significantly. Any effort is needed to use the least anesthetic drug for maintaining the anesthesia while avoiding hazards of cardio-pulmonary complications.

Methods

American Society of Anesthesiologists physical status classification I and II, Forty five elderly patients (≥ 60 years) who received transurethral resection of the prostate or transurethral resection of the bladder tumor were allocated randomly into three treatment groups. The DMT 0.5 group was designed as with dexmedetomidine 0.5 µg/kg while the DMT 1.0 group has a 1 µg/kg intravenous injection over 10 min before anesthetic induction. The Control group was designed to get a normal saline. Each group was compared regarding the maximum sensory block level, extension of anesthesia, degree of motor block, level of sedation, VAS score and complications.

Results

There were no significant differences among the 3 treatment groups regarding the maximum level of sensory block and motor block. However, the duration of sensory block was significantly longer in DMT 1.0 group than in the control group (P = 0.045). Both DMT 1.0 group (median = 3, range = 2-6) and DMT 0.5 group (median = 3, range = 1-6) showed a mean value of 3-4 Ramsay sedation score, which resulted in more excessive sedation and significantly greater incidence of bradycardia compared to the control group. No complications such as hypotension, nausea, tremor, and hypoxia were found during this investigation.

Conclusions

In elder patients, the DMT 1.0 group is effective in duration of sensory block and is superior in the aspect of prolonged duration of sensory block compared to the DMT 0.5 group.

A modified laparoscopic ureterolithotomy by pulling ureter with Carter-Thomason fascial closure and ureter incision by broken 15th blade

BACKGROUND AND AIMS

To evaluate the efficacy and safety of a modified laparoscopic ureterolithotomy for the treatment of upper ureteral stones; this method involved the use of a Carter-Thomason fascial closure device, a broken 15th blade.

MATERIAL AND METHODS

From February 2009 to December 2012, 38 patients with unilateral upper ureteral stones were examined and classified into 2 groups: one group underwent conventional laparoscopic ureterolithotomy (n = 21) and the other group underwent modified laparoscopic ureterolithotomy (n = 17). The modified laparoscopic ureterolithotomy consisted of the use of a Carter-Thomason fascial closure to extract the black silk along with the nylon tape. The ureter incision was made with a modified instrument consisting of a needle holder with a broken 15th blade tip.

RESULTS AND CONCLUSIONS

Patient demographics were similar in both groups. No significant differences were detected between the conventional laparoscopic ureterolithotomy and modified laparoscopic ureterolithotomy groups with respect to operating time, estimated blood loss, and stone clearance rates. Drain-indwelling times were significantly shorter in modified laparoscopic ureterolithotomy patients than in conventional laparoscopic ureterolithotomy patients (3.2 ± 1.3 vs 4.7 ± 1.5 days). Hospital stay was significantly lesser in modified laparoscopic ureterolithotomy patients than in conventional laparoscopic ureterolithotomy patients (4.3 ± 1.2 vs 5.2 ± 1.2 days). No differences were detected in the ureteral stent indwelling time for the two groups. The use of the Carter-Thomason fascial closure facilitated ureter handling, and the use of a needle holder with a broken 15th blade tip enabled a sharp and precise ureteral incision. Our method allows early removal of the drain and thus earlier patient discharge.

Effect of temperature on the treatment of domestic wastewater with a staged anaerobic fluidized membrane bioreactor

A laboratory staged anaerobic fluidized membrane bioreactor (SAF-MBR) system was applied to the treatment of primary clarifier effluent from a domestic wastewater treatment plant with temperature decreasing from 25 to 10 °C. At all temperatures and with a total hydraulic retention time of 2.3 h, overall chemical oxygen demand (COD) and biochemical oxygen demand (BOD5) removals were 89% and 94% or higher, with permeate COD and BOD5 of 30 and 7 mg/L or lower, respectively. No noticeable negative effects of low temperature on organic removal were found, although a slight increase to 3 mg/L in volatile fatty acids concentrations in the effluent was observed. Biosolids production was 0.01-0.03 kg volatile suspended solids/kg COD, which is far less than that with aerobic processes. Although the rate of trans-membrane pressure at the membrane flux of 9 L/m(2)/h increased as temperature decreased, the SAF-MBR was operated for longer than 200 d before chemical cleaning was needed. Electrical energy potential from combustion of the total methane production (gaseous and dissolved) was more than that required for system operation.

The correlation between the first heart sound and cardiac output as measured by using digital esophageal stethoscope under anaesthesia

OBJECTIVE

The use of an esophageal stethoscope is a basic heart sounds monitoring procedure performed in patients under general anesthesia. As the size of the first heart sound can express the left ventricle function, its correlation with cardiac output should be investigated. The aim of this study was to investigate the effects of cardiac output (CO) on the first heart sound (S1) amplitude. Methods : Six male beagles were chosen. The S1 was obtained with the newly developed esophageal stethoscope system. CO was measured using NICOM, a non-invasive CO measuring device. Ephedrine and beta blockers were administered to the subjects to compare changes in figures, and the change from using an inhalation anesthetic was also compared.

RESULTS

The S1 amplitude displayed positive correlation with the change rate of CO (r = 0.935, p < 0.001). The heart rate measured using the esophageal stethoscope and ECG showed considerably close figures through the Bland-Altman plot and showed a high positive correlation (r = 0.988, p < 0,001).

CONCLUSION

In beagles, the amplitude of S1 had a significant correlation with changes in CO in a variety of situations.

Correlation of blood pressure and the ratio of S1 to S2 as measured by esophageal stethoscope and wireless bluetooth transmission

Objective : Esophageal stethoscope has the advantage of being non-invasive, easily placed and capability to monitor the heart sound. This study was designed to determine whether the ratio of S1 to S2 analyzed by esophageal stethoscope and wireless bluetooth transmission can be accurate indicator that express the correlation with blood pressure.

METHODS

Total 33 adult male and female without cardiac disorder and with normal heart rhythm were selected randomly as the subjects of this Study. Two microphones were used with one for acquisition of heart sound by connecting it to the esophageal stethoscope while the other was used to measure the background noise in the operating room. After having transmitted the heart sound measured with the esophageal stethoscope to the receiver by using bluetooth module, it was saved in PC and outputted, following removal of noise in the operating room and the respiratory sound. S1 and S2 were measured with computation of the ratio of S1 to S2. Correlations between the systolic blood pressure with each of the S1, S2 and ratio of S1 to S2 were examined by using correlation analysis.

RESULTS

The ratio of S1 to S2 displayed the highest correlation with the systolic blood pressure, with S1 and S2 also displaying positive correlation with the systolic blood pressure.

CONCLUSION

As the result of analysis of the heart sound and the systolic blood pressure measured by using the esophageal stethoscope, the radio of S1 to S2 displayed greater correlation with the systolic blood pressure in comparison to the S1.

Germline mutations and genotype-phenotype correlations in patients with apparently sporadic pheochromocytoma/paraganglioma in Korea

The aim of our study was to assess the frequency of germline mutations and develop the genetic testing strategy in patients with apparently sporadic pheochromocytoma/paraganglioma (PPGL) in Korea. We included 53 patients diagnosed with non-syndromic PPGL without a family history of PPGLs in three referral centers from 2004 to 2011. Succinate dehydrogenase complex B (SDHB), SDHD, Von Hippel-Lindau (VHL), and rearranged during transfection (RET) genes were examined by direct sequencing and multiple ligation-dependent probe amplification. The study patients were composed of 26 men and 27 women, and mean age was 50.1 ± 13.5 years. The frequency of germline mutations was 13.2% (7/53): RET (n = 2), VHL (n = 1), SDHB (n = 2), and SDHD (n = 2). Six of seven mutation carriers were diagnosed before the age of 50. One of two patients harboring an SDHB mutation had malignant PPGLs. One patient with multifocal head and neck paraganglioma (PGL) and pheochromocytoma (PHEO) carried a SDHD mutation. The carriers of germline mutations in patients with apparently sporadic PPGL were 13.2% in our study. We recommend genetic testing in patients below 50 years and SDHD genetic testing in patients with multifocal PPGLs. In malignant PPGLs, SDHB genetic testing may be performed.

The effect of xylometazoline spray for expansion of nasal cavity

Background

During nasotracheal intubation it is important to have proper pretreatment for nasal mucosa constriction and nasal cavity expanding. Nasal packing of epinephrine gauze is widely used as well as xylometazoline. The aim of this study was to compare and evaluate the efficacy of prophylactic intranasal spray of xylometazoline against epinephrine gauze packing in expanding the nasal cavity.

Methods

Volunteers (n = 32) in their twenties without nasal disease such as septal deviation or rhinitis were enrolled in the study. The more patent nostril in each subject was measured by acoustic rhinometry as the base value. After intranasal spray of xylometazoline, the same nostril was remeasured by same method. Twenty four hours later, intranasal packing of epinephrine gauze was done and the same treatment was done. Subject preferences about the procedures were asked.

Results

There were significant difference among treatments (base value: 0.582 ± 0.164 cm², xylometazoline spray: 0.793 ± 0.165 cm², epinephrine gauze packing: 0.990 ± 0.290 cm²) in acoustic rhinometry. While the epinephrine gauze packing showed more efficient mucosa constriction, subjects preferred xylometazoline spray.

Conclusions

Even though xylometazoline spray was less effective than epinephrine gauze packing, the simplicity and convenience compensated. In patients undergoing nasotracheal intubation, xylometazoline spray can be an alternative to epinephrine gauze packing.

The association between the self-perception period of overactive bladder symptoms and overactive bladder symptom scores in a non-treated population and related sociodemographic and lifestyle factors

AIMS

To investigate the association between the self-perception period of OAB symptoms (SP-OAB) and the overactive bladder symptom score (OABSS), along with related sociodemographic and lifestyle factors.

METHODS

This was a cross-sectional study comprised of 192 men aged 40 years and older who participated in a prostate examination survey between February and May 2009 and proved to have OAB. Survey questionnaires included items on the OABSS and the SP-OAB assessed by the OABSS. Various sociodemographic and lifestyle factors were also included.

RESULTS

The average SP-OAB period was 24.72 ± 45.75 months and became significantly longer as the severity of OAB increased in correlation analysis (coefficient = 0.501, p < 0.001). Age, education, income, regular check-up, health maintenance and occupation were all risk factors in both OABSS and SP-OAB in univariate analysis. Body mass index (BMI), family size and SP-OAB were risk factors for OABSS in univariate analysis. Age and regular check-ups were factors in both OABSS and SP-OAB in multivariate analysis. BMI, income and SP-OAB were risk factors for OABSS.

CONCLUSION

These findings suggest that the SP-OAB is an independent risk factor for OAB progression and that various sociodemographic and lifestyle factors affect OABSS. The self-perception period should be considered in the treatment and prevention of OAB symptoms.

Sociodemographic and lifestyle factors affecting the self-perception period of lower urinary tract symptoms of international prostate symptom score items

AIMS

This study investigated the influence of sociodemographic and lifestyle factors on the lower urinary tract symptom (LUTS) self-perception period and International Prostate Symptom Score.

METHOD

This cross-sectional study examined 209 men aged ≥ 40 years with non-treated LUTS who participated in a prostate examination survey. Questions included International Prostate Symptom Score (IPSS) items with self-perception periods for each item. Sociodemographic and lifestyle factors were also assessed. Participants were divided by mild LUTS (IPSS less than 8) and moderate-to-severe LUTS (IPSS 8 or higher).

RESULTS

Self-perception period of the moderate-to-severe LUTS (n = 110) was affected by BMI; the self-perception period of the mild LUTS (n = 90) was affected by age, income, occupation and concomitant disease. Moderate-to-severe LUTS were affected by self-perception period (p = 0.03). Self-perception period was affected by concern for health (p = 0.005) by multivariate analysis, and self-perception period of mild LUTS was affected by BMI (p = 0.012). Moderate-to-severe LUTS were affected by age, number of family members, concern for health and drinking (p < 0.05, respectively) by multivariate analysis.

CONCLUSION

Lower urinary tract symptom was affected by self-perception period. In moderate-to-severe LUTS, age, concern for health and drinking were affecting factors of self-perception period.

Treatment satisfaction with low-dose tamsulosin for symptomatic benign prostatic hyperplasia: results from a multicentre cross-sectional survey

AIMS

To evaluate the efficacy and treatment satisfaction with low-dose (0.2 mg) tamsulosin in patients with symptomatic benign prostatic hyperplasia (BPH), and to investigate individual lower urinary tract symptoms according to treatment satisfaction.

METHODS

A cross-sectional study was conducted in a total sample of 2574 patients from multiple centres. International Prostate Symptom Score (IPSS), prostate volume, uroflowmetry and combined medications were reviewed. Detailed questionnaires were used to assess treatment satisfaction and IPSS 8 weeks after treatment with low-dose tamsulosin.

RESULTS

After 8 weeks of treatment with low-dose tamsulosin, IPSS improved significantly. Among the 2574 patients, 1,630 (63.42%) were satisfied and 940 patients (36.50%) were dissatisfied with low-dose tamsulosin. The reasons for dissatisfaction included efficacy problems (84.66%) and side effects (3.72%). Treatment satisfaction was affected by symptom duration, baseline IPSS, and prostate size (p = 0.0441, < 0.001, < 0.009, respectively). IPSS voiding (IPSS-V) and IPSS storage (IPSS-S) after treatment differed significantly depending on the degree of satisfaction (p < 0.001). IPSS-V after treatment did not improve in patients who were 'not satisfied' or 'totally not satisfied' (p = 0.170, 0.240, respectively). All the individual IPSS items except urgency (p = 0.1436) varied significantly with the degree of satisfaction (p < 0.001).

CONCLUSIONS

Treating symptomatic BPH with low-dose tamsulosin improved IPSS, but more than one-third of patients were dissatisfied with the treatment. The main reason for dissatisfaction was efficacy problems, and the degree of satisfaction was related to symptom duration, baseline IPSS, and prostate size, and also to IPSS-V. In patients with severe LUTS, the tamsulosin dose should be increased earlier.

Wire-reinforced endotracheal tube fire during tracheostomy -A case report-

Every operation could have a fire emergency, especially in the case of a tracheostomy. When a flammable gas meets a source of heat, the danger of fire is remarkable. A tracheal tube filled with a high concentration of oxygen is also a great risk factor for fire. Intra-tracheal tube fire is a rare, yet critical emergency with catastrophic consequences. Thus, numerous precautions are taken during a tracheostomy like, use of a special tube to prevent laser damage, ballooning of the tube with normal saline instead of air, and dilution of FiO₂ with helium or nitrogen. Since the first recorded cases on tube fires, most of the fires were initiated in the balloon and the tip. In the present case report, however, we came across a fire incidence, which originated from the wire.

The relaxant effect of ginseng saponin on the bladder and prostatic urethra: an in vitro and in vivo study

AIM

To assess the effects of ginseng saponin on relaxation of the bladder and prostatic urethra and to determine its mechanism of action.

MATERIALS AND METHODS

For the in vitro study, prostatic urethra muscle strips were harvested from 18 male New Zealand rabbits. The strips were mounted in organ baths and connected to force displacement transducers. After stabilization, maximal tissue contractions were obtained by the application of phenylepinephrine to the urethra strips, and a dose-response curve for ginseng saponin was constructed (10(-6)-10(-2)M). After pretreatment of urethra strips with N-nitro-L-arginine methyl ester (L-NAME), another dose-response curve for ginseng saponin was constructed. For the in vivo study, we used adult male Sprague-Dawley rats divided into three groups [control, partial bladder outlet obstruction (PBOO) and saponin-fed groups], and we monitored the vesical pressure (P(ves)) and urethral perfusion pressure (UPP).

RESULTS

The ginseng saponin induced a significant dose-dependent relaxant effect on the prostatic urethra strips. A significant relaxant effect of ginseng saponin was observed from 10(-3)M, and ginseng saponin significantly relaxed urethra strips by 50.2 ± 20.26% at 10(-2)M. The relaxant effect was partially inhibited with L-NAME pretreatment. In the in vivo study, the change in UPP between baseline and relaxation was significantly higher in the saponin group than in the control or PBOO group (p < 0.001). The saponin group showed a significantly lower baseline P(ves) than the PBOO group.

CONCLUSIONS

We observed a significant relaxation effect of ginseng saponin on the bladder and prostatic urethra in both in vitro and in vivo studies. The mechanism by which ginseng saponin induces relaxation appears to involve the nitric oxide/nitric oxide synthase pathway.

Loading behavior of Pt nanoparticles on the surface of multiwalled carbon nanotubes having defects formed via microwave treatment

We developed a simple and efficient method to load Pt nanoparticles (NPs) uniformly on defects generated in multiwalled CNTs (MWCNTs) without using reduction agents or organic reagents. Defects on the surfaces of MWCNTs were artificially generated by microwave treatment at various exposure times. Nucleation of Pt NPs occurs on the defect sites spontaneously due to an innate electropotential difference. Because of the correlation between defects and Pt NPs, we were able to control the size of Pt NPs by changing defect size, quantity and distribution, which was confirmed by Raman spectroscopy and TEM. After microwave treatment for 3 min, more uniform and smaller Pt NPs were observed. Also, the defects via microwave treatment make adhesion of Pt NPs stronger, which can be helpful to improve the reliability for applications. Finally, the methanol oxidation behavior of MWCNTs with Pt NPs was examined by cyclic voltammetry (CV).

Substance P sensitizes P2X3 in nociceptive trigeminal neurons

Peripheral inflammation produces pain hypersensitivity by sensitizing nociceptors. Potentiation of P2X3 receptor activity in nociceptors may play an important role in this peripheral sensitization. However, we do not fully understand how P2X3 activity is elevated in inflammation. Thus, we investigated whether P2X3 activity in trigeminal nociceptive neurons is regulated by the neurokinin-1 (NK-1) receptor that is activated by an inflammatory mediator, substance P. Single-cell RT-PCR and immunohistochemistry revealed that NK-1 in nociceptive neurons was mainly co-expressed with P2X3. Ca(2+) imaging and whole-cell patch-clamp recordings indicated that both substance P and Sar-substance P, a selective NK-1 agonist, significantly potentiated α,β-meATP-induced currents and [Ca(2+)](i) responses in nociceptive neurons. These potentiating effects were completely blocked by GR82334, a specific NK-1 antagonist. Our results demonstrate that substance P sensitizes P2X3 receptor through the activation of NK-1, thus warranting these receptors as possible targets for pain therapy in the orofacial region.

ABBREVIATIONS

α,β-methylene adenosine 5'-triphosphate (ATP), α,β-meATP; neurokinin-1, NK-1; single-cell reverse-transcription polymerase chain-reaction, single-cell RT-PCR; [Sar(9),Met(O(2))(11)]-substance P, Sar-substance P.

Transient cortical blindness after heart surgery in a child patient -A case report-

Visual loss occurring after pediatric cardiac surgery employing cardiopulmonary bypass (CPB) is relatively rare but the risk is substantial. Compromised cerebral perfusion due to a CPB related micro-embolization and inflammatory vascular changes as well as reduced oxygen carrying capacity in hemodilution and hypothermia during CPB might be major contributing factors to the development of postoperative visual loss after cardiac surgery with CPB. A case of immediate but transient postoperative visual loss was encountered in a 21-month-old male who underwent tricuspid valve surgery. Despite routine intraoperative measures to maintain an adequate perfusion pressure throughout the procedure, postoperative computed tomography revealed a subacute infarct in his occipital lobe. Recovery began on postoperative day 28, and the patient's vision was restored by 31 days.

A portable inhalational induction device provides co-operative induction of anaesthesia in preanaesthetic area for children

BACKGROUND

We introduce a new, simple portable inhalational induction device (PD) that provides co-operative inhalational induction of anaesthesia using N(2)O and subsequent sevoflurane in the preanaesthetic induction area in children.

METHODS

Forty-five children (30 to 94 months old age, <35 kg) who were scheduled to undergo simple operations were assigned randomly to one of three regimens. Patients were encouraged by their parents to inhale N(2)O followed by sevoflurane (PD N(2)O-sevo group) or sevoflurane (PD sevo group) using a portable inhalational induction device in the preanaesthetic induction area until they were unable to respond to their names. They were then transferred to the operating room while maintaining inhalation of sevoflurane via the device. The control group underwent conventional inhalational induction in the operating room with the parents in attendance.

RESULTS

Patients in the PD N(2)O-sevo group had a higher co-operative inhalation frequency than the patients in the PD sevo or the control group. Anaesthesia induction in the PD N(2)O-sevo and the PD sevo groups were faster than in the control group. Parent satisfaction score (0-100) was higher for the PD N(2)O-sevo group than for the control group.

CONCLUSIONS

A new portable inhalational induction device allows faster induction in co-operation with parents present in the preanaesthetic induction area compared to conventional inhalational induction in the unfamiliar operating room with the parents in attendance.

The effects of intravesical chemoimmunotherapy with gemcitabine and Bacillus Calmette-Guérin in superficial bladder cancer: a preliminary study

This prospective study investigated the long-term effects of intravesical chemoimmunotherapy with gemcitabine (GEM) and bacillus Calmette-Guérin (BCG; n = 36) versus BCG alone (n = 51) for the treatment of superficial bladder cancer. For the chemoimmunotherapy (GEM + BCG) group, GEM (1000 mg) was instilled immediately after transurethral resection of bladder tumour (TURBT) and again (2000 mg) 1 week later. From 2 to 7 weeks after TURBT, BCG was instilled into the bladder of all patients once weekly. The recurrence-free period of the GEM + BCG group (24.13 months) was significantly longer than that of the BCG monotherapy group (19.81 months). The overall recurrence rate was similar between the groups, although at 6 and 9 months post-TURBT, GEM + BCG produced a significantly lower rate of recurrence compared with BCG alone. This study suggests that intravesical chemoimmunotherapy with GEM + BCG is effective in reducing early tumour recurrence and in prolonging the recurrence-free period of superficial bladder cancer.

The effects of midazolam administered postoperatively on emergence agitation in pediatric strabismus surgery

Background

The present study tested the effect of midazolam administration after sevoflurane anesthesia against emergence agitation in children in the recovery phase.

Methods

A total of 60 children presenting for ophthalmic surgery under sevoflurane anesthesia were randomly placed in four groups from Group I to Group IV. Before the end of the surgery, we injected normal saline 2 ml in Group I and Group IV. We administered a 2-ml mixture of midazolam 0.025 mg/kg and midazolam 0.050 mg/kg to Group II and Group III respectively. Among the patients with agitation scores 4 or 5 in the peostanesthesia care unit (PACU), Group IV patients were intravenously given a 1-ml mixture of midazolam 0.025 mg/kg and normal saline up to 3 times. Agitation parameters, anesthesia recovery times, and the total administration amounts of midazolam were measured.

Results

Extubation time was significantly longer and maximum agitation scores higher in Group III than in Group I. The rate of the length of the period when the agitation score was 4 or 5 out of the length of stay in the PACU was significantly lower in Group II, Group III, and Group IV than in Group I. The length of stay in the PACU was significantly longer in Group III, and Group IV than in Group I.

Conclusions

For pediatric patients under sevoflurane anesthesia, postoperative midazolam administration slightly prolonged the length of stay in the PACU. But it effectively reduced emergence agitation without any side effects.

Arthrodesis of the knee using cannulated screws

We retrospectively evaluated eight patients who underwent arthrodesis of the knee using cannulated screws. There were six women and two men, with a mean age of 53 years. The indications for arthrodesis were failed total knee arthroplasty, septic arthritis, tuberculosis, and recurrent persistent infection. Solid union was achieved in all patients at a mean of 6.1 months. One patient required autogenous bone graft for delayed union. One suffered skin necrosis which was treated with skin grafting. The mean limb-length discrepancy was 3.1 cm. On a visual analogue scale, the mean pain score improved from 7.9 to 3.3. According to the Knee Injury and Osteoarthritis Outcome score quality of life items, the mean score improved from 38.3 pre-operatively to 76.6 at follow-up. Cannulated screws provide a high rate of union in arthrodesis of the knee with minimal complications, patient convenience, and a simple surgical technique.

The effect of bupivacaine.HCl on the physical properties of neuronal membranes

Fluorescent probe techniques were used to evaluate the effect of bupivacaine.HCl on the physical properties (transbilayer asymmetric lateral and rotational mobilities, annular lipid fluidity and protein distribution) of synaptosomal plasma membrane vesicles (SPMVs) isolated from bovine cerebral cortex. An experimental procedure was used based on selective quenching of both 1,3-di(1-pyrenyl)propane (Py-3-Py) and 1,6-diphenyl-1,3,5-hexatriene (DPH) by trinitrophenyl groups, and radiationless energy transfer (RET) from the tryptophans of membrane proteins to Py-3-Py. Bupivacaine.HCl increased the bulk lateral and rotational mobilities, and annular lipid fluidity in SPMVs lipid bilayers, and had a greater fluidizing effect on the inner monolayer than that of the outer monolayer. The magnitude of increasing effect on annular lipid fluidity in SPMVs lipid bilayer induced by bupivacaine.HCl was significantly far greater than magnitude of increasing effect of the drug on the lateral and rotational mobilities of bulk SPMVs lipid bilayer. It also caused membrane proteins to cluster. These effects of bupivacaine.HCl on neuronal membranes may be responsible for some, though not all, of the local anesthetic actions of bupivacaine.HCl.

Predictors of slow flow during primary percutaneous coronary intervention: an intravascular ultrasound-virtual histology study

OBJECTIVES

Slow flow phenomenon is a serious complication of percutaneous coronary intervention (PCI) and is associated with a poor prognosis. We sought to evaluate the characteristics of lesions predisposing to the slow/no-reflow phenomenon during primary PCI in patients with acute myocardial infarction.

METHODS

The study subjects consisted of 57 consecutive patients (mean age 58.5 (SD 14.5) years, 45 males) who underwent primary PCI for acute myocardial infarction and intravascular ultrasound-virtual histology (IVUS-VH) examination. Slow flow was defined as <or= thrombolysis in myocardial infarction grade 2 after PCI.

RESULTS

Slow flow developed in 12 patients (eight males). Patients with slow flow were likely to be older (67.5 (13.8) years vs 56.2 (13.9) years, p = 0.015), had more cardiogenic shock (16.7% vs 2.2%, p = 0.046), larger fibrofatty volume over the entire lesion length (36.7 (25.5) mm(3) vs 18.0 (18.6) mm(3), p = 0.006), higher remodelling index (1.10 (0.17) vs 0.99 (0.16), p = 0.043), larger plaque area (16.2 (5.4) mm(2) vs 12.5 (4.9) mm(2), p = 0.025), fibrous area (8.0 (3.3) mm(2) vs 5.4 (3.0) mm(2), p = 0.014) and fibrofatty area (2.7 (2.2) mm(2) vs 1.3 (1.6) mm(2), p = 0.016) at the minimal lumen site than those without slow flow (37 males). Multivariate analysis revealed that the fibrofatty volume over the entire lesion length was the only independent factor (beta = 0.359, 95% confidence interval 0.002 to 0.012, p = 0.006) for slow flow during primary PCI.

CONCLUSIONS

This study suggests that slow flow may be dependent on the tissue characterisation (fibrofatty volume) of the underlying lesion at the time of the primary PCI for acute myocardial infarction.

The performance of the sludge pretreatment system with venturi tubes

This research investigates the feasibility of the venturi cavitation system (VCS) for the sludge pretreatment to increase biodegradability. The performances of the VCS depended on the inclination angle of the venturi outlet, and better results obtained with 12 degrees than with 8 degrees or 15 degrees . Although it is energy efficient to use several venturies in series, the number of the venturies should be determined with detailed fluid dynamic calculations. The linear relationship between total solid (TS) concentration and the increases in soluble chemical oxygen demand (Delta SCOD) was observed for both wasted activated sludge (WAS) and primary sludge, which might be related to the better conditions for cavitation development at high TS concentrations even with higher viscosity. The VCS achieved better energy efficiency in terms of Delta SCOD/kJ compared to high-speed homogenizer (HSH). On the other hand, the VCS showed a similar energy efficiency for mixed sludge with 1.8% TS, but lower efficiency for WAS with 4% TS when compared to ultrasonic disintegration.