DFTB+, a software package for efficient approximate density functional theory based atomistic simulations

DFTB+ is a versatile community developed open source software package offering fast and efficient methods for carrying out atomistic quantum mechanical simulations. By implementing various methods approximating density functional theory (DFT), such as the density functional based tight binding (DFTB) and the extended tight binding method, it enables simulations of large systems and long timescales with reasonable accuracy while being considerably faster for typical simulations than the respective ab initio methods. Based on the DFTB framework, it additionally offers approximated versions of various DFT extensions including hybrid functionals, time dependent formalism for treating excited systems, electron transport using non-equilibrium Green's functions, and many more. DFTB+ can be used as a user-friendly standalone application in addition to being embedded into other software packages as a library or acting as a calculation-server accessed by socket communication. We give an overview of the recently developed capabilities of the DFTB+ code, demonstrating with a few use case examples, discuss the strengths and weaknesses of the various features, and also discuss on-going developments and possible future perspectives.

Treatment Strategy for Persistent Sciatic Artery and Novel Classification Reflecting Anatomic Status

BACKGROUND

Persistent sciatic artery (PSA) is a relatively rare congenital variant of the lower limb vasculature and can have highly variable clinical presentations. The purpose of this study was to analyze the relationship between PSA anatomy and clinical presentation, and to suggest an optimal management strategy.

METHODS

Between 2001 and 2014, 24 PSAs in 19 patients were diagnosed by computed tomography and referred to the vascular surgery department. Patient demographics, types of PSA and femoral artery, aneurysmal changes, symptoms, and treatment methods were assessed. Additionally, all English literature from 1964 to 2014 was reviewed and compared using the PubMed database (224 PSAs in 171 patients).

RESULTS

PSA was diagnosed in 10 men (52.6%) and nine women (47.4%). PSAs were bilateral in five patients (26.3%) and symptomatic in 12 patients, while in seven patients PSA was found incidentally. According to the Pillet-Gauffre classification, Type 2a was the most common variant (n = 15/24, 62.5%), with unclassifiable types in two limbs. Compared with cases in the literature, the PSA occlusion rate in this study was higher (n = 10/24, 41.7% vs. n = 54/224, 27.5%), but aneurysm incidence was higher in the literature cases (n = 5/24, 20.8% vs. n = 112/224; 50.7%). In this study, 16 limbs (66.6%) were treated conservatively, and six limbs were treated by open surgery, including four bypasses, one amputation, and one thrombo-embolectomy. Endovascular coil embolization was performed in one limb, and a hybrid procedure with stent graft was performed in one limb with PSA aneurysm. Based on the present series and the literature review, a new classification system and treatment option is proposed according to the anatomic status and the presence of aneurysm. According to the new classification, class III was the most common in both the present study (18/24; 75%) and the literature review, and the presence of aneurysm was the most important determinant of surgical treatment.

CONCLUSIONS

The new classification system is simple and provides guidance for management. Limb anatomy of the femoral artery system and the presence of PSA aneurysm should be considered when selecting the optimal treatment. The risk of embolism from the presence of aneurysm is an important factor for treatment, and bypass surgery is mostly required in classes III and IV.

Repeated cessation and resumption of resistance training attenuates increases in arterial stiffness

Although high-intensity resistance training (RT) increases arterial stiffness, removing weightlifting stimuli returns arterial stiffness to baseline levels within relatively short periods during 4-8 weeks. This study investigates the effects of repeated RT cessation and resumption on arterial stiffness. Eighteen young healthy subjects were randomly assigned to a group that performed continuous RT (CRT, n=9) and a group that performed periodic RT (PRT, n=9). Both groups performed RT at 75% of one repetition maximum for 3 days per week. The CRT group continuously trained for 16 weeks, whereas the PRT group performed 3 cycles of 4 weeks training, with 2 weeks detraining intervals between cycles. The carotid-femoral pulse wave velocity in the CRT group significantly increased (P<0.05) at 4, 6, 10, 12, 16 and 20 weeks from baseline, whereas in the PRT group it significantly increased (P<0.05) after 4, 10 and 16 weeks from baseline, and was significantly lower (P<0.05) than that of the CRT group after 6, 10, 12, 16 and 20 weeks. Muscle mass and strength in the both groups significantly increased after 16 weeks from baseline and persisted for 20 weeks (P<0.05). These results suggest that PRT, including short-term repeated cessation and resumption, attenuates increases in arterial stiffness.

Conversion of twice-daily tacrolimus to once-daily tacrolimus formulation in stable pediatric kidney transplant recipients: pharmacokinetics and efficacy

The pharmacokinetics, efficacy and safety of once-daily tacrolimus formulation (Tac-OD) were assessed in 34 stable pediatric kidney transplant recipients. Enrolled patients received their dose of twice-daily tacrolimus formulation (Tac-BID) on study Days 0 through 7. On the morning of study Day 8, the total daily doses for patients were converted to Tac-OD on a 1:1 basis and maintained on a once-daily morning dosing regimen. Tacrolimus pharmacokinetic profiles were obtained on study Days 7, 14 and 28 (after dose adjustment). Although the mean C0 concentrations (4.10 ± 1.16-3.53 ± 1.10 ng/mL, p = 0.004), and AUC0-24 (151.8 ± 41.6-129.8 ± 39.3 ng h/mL, p < 0.001) were decreased significantly after a 1:1 based conversion, there was high interindividual variability. The dose of Tac-OD was decreased in 26.5% and increased in 44.1% of patients. The resultant tacrolimus dose and pharmacokinetic profiles on study Day 28 were comparable to those on Day 7. There were no serious adverse events. In conclusion, Tac-BID can be safely converted to Tac-OD in stable pediatric kidney transplant patients with the heightened therapeutic drug monitoring. Effects of drug conversion on the cardiovascular risk factors, neurological side effects and adherence should be further evaluated.

Characterization of NODs and TLRs in innate immune response of human cementoblast cells

OBJECTIVES

Microbial Pattern-recognition receptors (PRRs), such as Toll-like receptors (TLRs) and the nucleotide-binding oligomerization domains (NODs), are essential for mammalian innate immune response. In this study, we examined the characterization of NODs and TLRs on innate immune responses in human cementoblast (HCEM) cells.

MATERIALS AND METHODS

The gene expression of NODs and TLRs was examined by RT-PCR. Interleukin-6 (IL-6) and Interleukin-8 (IL-8) productions in culture supernatants were measured by ELISA. Western blot analysis was performed to determine the degradation of IκB-α and Mitogen activated protein kinase (MAPK) activation in response to their agonist.

RESULTS

The levels of NODs and TLRs were apparently expressed in HCEM cells. Although a few gene levels were weak in intact cells, the stimulation by their agonists increased the gene expression of TLRs. NODs and TLRs led to the production of IL-6 or IL-8 and the degradation of IκB-α and MAPK activation in HCEM cells. Combination treatment of NOD1 or NOD2 agonists with TLRs agonists did not influence the production of IL-6 and IL-8 in HCEM cells.

CONCLUSIONS

Our results indicate that NODs and TLRs are functionally expressed in HCEM cells and can trigger innate immune responses. However, NOD1 and NOD2 may not be cooperated with TLRs to elicit an immune response in HCEM cells.

Direct peroral cholangioscopy using an ultraslim upper endoscope for management of residual stones after mechanical lithotripsy for retained common bile duct stones

BACKGROUND AND STUDY AIMS

The incidence of residual stones after mechanical lithotripsy for retained common bile duct (CBD) stones is relatively high. Peroral cholangioscopy using a mother-baby system may be useful for confirming complete extraction of stones, but has several limitations regarding routine use. We evaluated the role of direct peroral cholangioscopy (DPOC) using an ultraslim upper endoscope for the evaluation and removal of residual CBD stones after mechanical lithotripsy.

PATIENTS AND METHODS

From August 2006 to November 2010, 48 patients who had undergone mechanical lithotripsy for retained CBD stones with no evidence of filling defects in balloon cholangiography were recruited. The bile duct was inspected by DPOC after balloon cholangiography. Detected residual CBD stones were directly retrieved with a basket or balloon catheter under DPOC. The incidence of residual stones detected by DPOC, and the success rate of residual stone retrieval under DPOC were investigated.

RESULTS

DPOC was successfully performed in 46 of the 48 patients (95.8%). Of these, 13 patients (28.3%) had residual CBD stones (mean number 1.4, range 1-3; mean diameter 4.5 mm, range 2.3-9.6). The residual stones were removed directly under DPOC in 11 of these patients (84.6%). There were no complications associated with DPOC or stone removal.

CONCLUSION

DPOC using an ultraslim upper endoscope is a useful endoscopic procedure for the evaluation and extraction of residual stones after mechanical lithotripsy for retained CBD stones.

Effect-site concentration of remifentanil for nasotracheal versus orotracheal intubation during target-controlled infusion of propofol

The concentration of remifentanil required for acceptable nasotracheal intubation in adults after target-controlled infusion (TCI) of propofol without neuromuscular blockade was compared with that required for orotracheal intubation. Twenty-five patients undergoing oral and maxillofacial surgery received nasotracheal intubation and 25 undergoing ear, nose and throat surgery received orotracheal intubation. Anaesthesia was induced with propofol TCI at a target effect-site concentration of 5.0 μg/ml. The 50% and 95% effective concentrations (EC(50) and EC(95), respectively) for remifentanil, calculated using isotonic regression, were 5.40 and 6.85 ng/ml, respectively, in the orotracheal group and 5.75 and 7.43 ng/ml in the nasotracheal group. The EC(50) (± SD) values for remifentanil, calculated using a modified Dixon's up-and-down method, were 6.08 ± 0.75 and 5.58 ± 0.75 ng/ml for nasotracheal and orotracheal intubation, respectively. Effect-site remifentanil concentrations did not differ significantly between the two groups of patients. Coadministration of propofol and remifentanil can provide acceptable conditions for nasotracheal intubation without neuromuscular blockade.

Reduction of microemulsion propofol-induced injection pain via target-controlled remifentanil infusion

The intravenous injection of microemulsion propofol to induce anaesthesia causes more intense and frequent pain than lipid emulsion propofol. This study investigated whether different target effect-site concentrations of remifentanil could prevent pain due to microemulsion propofol injection. In total, 96 patients were randomly assigned to one of three groups receiving target effect-site concentrations of remifentanil 0 (control group), 4 or 6 ng/ml, followed by injection with microemulsion propofol. Remifentanil pretreatment significantly reduced the incidence and severity of injection pain compared with the control group. Although no difference in pain reduction between the two remifentanil-treated groups was observed, those receiving a target effect-site concentration of 6 ng/ml exhibited an increased rate of complications, compared with those receiving 4 ng/ml. In conclusion, prior administration of remifentanil at a target effect-site concentration of 4 ng/ml is a useful strategy to decrease the injection pain of microemulsion propofol.

Preoperative determination of anatomic variations of the small saphenous vein for varicose vein surgery by three-dimensional computed tomography venography

Objective

To define the anatomical variations of small saphenous vein (SSV) for varicose vein (VV) surgery by three-dimensional computed tomography venography (3D-CTV) and to analyse the impact of this preoperative evaluation on surgical outcomes.

Methods

A total of 120 consecutive limbs with SSV insufficiency having undergone VV surgery from January 2005 until December 2007 were enrolled. The medical records and images were analysed retrospectively.

Results

The relationship between SSV and gastrocnemial vein (GNV) were categorized into two: (a) SSV and GNV drained to popliteal vein (PV) separately (100 limbs, 87%) and (b) SSV and GNV made common channel which drained to PV (15 limbs, 13%). Saphenopopliteal junction morphology was normal (75 limbs), severe tortuosity near PV (19 limbs), ampullary ectasia (4 limbs) and duplicated drainage to PV (2 limbs). No recurrence of VV was noted.

Conclusions

CTV can provide thorough preoperative anatomic information of the SSV variations and reduce the recurrence of VV.

Bolus Effective Dose of Ketamine for Preventing Withdrawal Movement on Injection of Rocuronium in Paediatric Patients

The bolus effective dose of ketamine required to prevent withdrawal movement on injection of rocuronium was determined in 27 paediatric patients undergoing elective surgery. A predetermined dose of ketamine was given intravenously on arrival in the operating room and anaesthesia (2.5% thiopental, 5 mg/kg) was administered 1 min later. After loss of consciousness, 1% rocuronium at 0.6 mg/kg was injected over 5 s and the presence or absence of withdrawal movement recorded. The effective dose of ketamine was determined using a modified Dixon up-and-down method with a step size of 0.1 mg/kg, successful prevention of withdrawal movement being defined as no response or movement at the wrist only. The bolus effective dose of ketamine for preventing withdrawal movement after injection of rocuronium following thiopental anaesthesia in 50% of paediatric patients (ED50) was 0.21 mg/kg according to the modified Dixon up-and-down method. Probit analysis indicated an ED50 of 0.18 mg/kg and an ED95 of 0.33 mg/kg. The latter was the most satisfactory dose in the clinical setting.

The cartilage intermediate layer protein gene is associated with lumbar disc degeneration in collegiate judokas

Lumbar disc degeneration is frequently seen in athletes. Lumbar disc diseases include a spectrum of diseases and/or symptoms, including lumbar disc degeneration. Some reports suggest an association between lumbar disc diseases and a functional single-nucleotide polymorphism (SNP;1184T/C, rs 2073711) of the cartilage intermediate layer protein ( CILP) gene. We hypothesized that lumbar disc degeneration occurrence may be significantly associated with SNP variants at the CILP gene in Japanese collegiate judo athletes. Eighty-nine Japanese judo athletes participated in this study. T2-weighted magnetic resonance imaging was used to define lumbar disc degeneration. Genotyping of the CILP gene (1184T/C) was performed using DNA sequencing. By using logistic regression analysis, significant associations of lumbar disc degeneration with the CILP C allele (odds ratio=4.1, 95% confidence interval: 1.57-10.71) and body weight (odds ratio=1.06, 95% confidence interval: 1.02-1.09) were observed. We conclude that the CILP gene 1184T/C polymorphism is a significant risk factor for lumbar disc degeneration occurrence in Japanese collegiate judo athletes.

Prevention of propofol-induced pain in children: combination of alfentanil and lidocaine vs alfentanil or lidocaine alone

BACKGROUND

Pain from a propofol injection is a common side-effect in paediatric patients. This prospective, randomized, double-blind study evaluated the efficacy of a combined pretreatment of alfentanil with lidocaine on the incidence and severity of propofol injection pain in children.

METHODS

After obtaining parental consent, 120 paediatric patients were allocated randomly into one of the three groups (n=40, in each). The patients in the alfentanil group received alfentanil 15 microg kg(-1) 90 s before the propofol injection. The patients in the lidocaine group received propofol 3 mg kg(-1) premixed with lidocaine 0.1% over a 15 s period. The patients in the combination group received both alfentanil and lidocaine.

RESULTS

The incidence of propofol injection pain (severity 2 or more) in the combination group (2.6%) was significantly lower than that in the alfentanil and lidocaine groups (30% and 38.5%, respectively) (P=0.001 and <0.001, respectively). No patient in the combination group complained of moderate or severe pain from propofol injection.

CONCLUSIONS

Our study demonstrated that the combination treatment of two different analgesic modalities, alfentanil and lidocaine, could prevent the moderate and severe pain on propofol injection, and reduce the incidence of mild pain compared with each drug alone.

Carbon dioxide and argon gas embolism during laparoscopic hepatic resection

During laparoscopic hepatic resection, an abrupt decrease in FE'CO(2) (from 28 mmHg to 9 mmHg) associated with near cardiac arrest occurred concomitantly with hepatic vein laceration and the use of an argon beam coagulator system. During venous gas embolism, transesophageal echocardiography (TEE) proved the transpulmonary passage of the gas. In the post-operative period, the patient developed pulmonary edema and made a full recovery after 5 days. This is a case report of a possible paradoxic carbon dioxide (CO(2)) and argon gas embolism by transpulmonary passage during laparoscopic hepatic resection.

The optimal dose of remifentanil for intubation during sevoflurane induction without neuromuscular blockade in children

The optimal dose of remifentanil needed to produce successful intubating conditions following inhalation induction of anaesthesia using 5% sevoflurane without the use of neuromuscular blocking drugs, was investigated in 25 children aged 3-10 years. Sixty seconds after inhalation induction of anaesthesia using sevoflurane 5% in 100% oxygen, a predetermined dose of remifentanil was injected over 30 s. The dose of remifentanil was determined using the modified Dixon's up-and-down method (0.2 microg x kg(-1) as a step size). The first patient was tested at 1.0 microg x kg(-1) remifentanil. Ninety seconds following the bolus administration of remifentanil, the child's trachea was intubated. The optimal bolus dose of remifentanil required for successful tracheal intubation was 0.56 (0.15) microg x kg(-1) in 50% of children during inhalation induction using 5% sevoflurane in the absence of neuromuscular blocking drugs. Using probit analysis, the 95% effective dose (ED(95)) of remifentanil was 0.75 microg x kg(-1) (95% confidence limits 0.63-1.38 microg x kg(-1)).

Mandibular symphyseal distraction osteogenesis with stepwise osteotomy in adult skeletal class III patient

This technical note reports the use of symphyseal distraction with stepwise osteotomy in a case of lower anterior crowding and rotation in the incisor area. This technique allows for easy dental decompensation and reduced presurgical orthodontic time in skeletal class III cases.

Awake nasotracheal intubation using fiberoptic bronchoscope in a pediatric patient with Freeman-Sheldon syndrome

The Freeman-Sheldon syndrome is a congenital disease primarily affecting the facial, limb and respiratory muscles that give rise to classical clinical features including typical whistling face and short webbed neck associated with difficult intubation. We present successful awake nasotracheal intubation in a 6-year-old patient with typical clinical features of Freeman-Sheldon syndrome by using fiberoptic bronchoscope on two separate occasions.

Laparoscopic distal pancreatectomy with preservation of the spleen and splenic vessels for benign pancreas neoplasm

BACKGROUND

Laparoscopic distal pancreatectomy to conserve the spleen is a beneficial operation for patients with benign and borderline malignancy in the pancreas. With this procedure, it is very desirable to preserve the splenic artery and vein as well.

METHODS

From May 2000 to July 2003, five laparoscopic distal pancreatectomies with preservation of the spleen and splenic vessels were performed for benign pancreas neoplasm at Ewha Womans University Mokdong Hospital in Seoul, Korea.

RESULTS

The postoperative pathologic diagnoses were two serous cystadenomas, two mucinous cystadenomas, and one solid and papillary epithelial tumor. The tumors ranged in size from 1.5 to 7 cm. Four trocars (10-15 mm) and a laparoscopic linear stapler were used for transection of the pancreas. The mean operation time was 348 min, and the mean length of the incision for extraction was 3.6 cm. The mean postoperative hospital stay was 10.4 days. There was no complication or mortality.

CONCLUSION

Laparoscopic distal pancreatectomy with preservation of the spleen and splenic vessels is a relatively safe and feasible option for the management of benign tumor or borderline malignancy in the distal pancreas.

Sex-based analysis of the outcome of laparoscopic cholecystectomy for acute cholecystitis

BACKGROUND

Complicated acute cholecystitis, for example when empyema or gangrene is present, is associated with increased postoperative morbidity and mortality rates. The aim of this study was to determine the correlation between sex, the severity of acute cholecystitis and the outcome of laparoscopic cholecystectomy.

METHODS

Of 674 patients in whom laparoscopic cholecystectomy was attempted, 348 had chronic cholecystitis and 326 had acute cholecystitis. The medical records of the latter were reviewed retrospectively.

RESULTS

The proportion of male patients significantly increased with the severity of cholecystitis: 37.4 per cent of those with chronic cholecystitis were men, compared with 44.4 per cent of those with uncomplicated acute cholecystitis and 57 per cent of those with complicated acute cholecystitis (P = 0.001). Multivariate analysis showed that advanced age (odds ratio 2.24; P = 0.004) and male sex (odds ratio 1.76; P = 0.029) independently predicted complicated acute cholecystitis. The conversion rate to open operation was 6.4 per cent in men and 5.9 per cent in women (P = 0.843). The postoperative complication rate was 10.3 and 8.2 per cent respectively (P = 0.528).

CONCLUSION

Male sex was identified as a risk factor for more severe acute cholecystitis, but outcome for men after laparoscopic cholecystectomy was not significantly different from that for women.

Risk factors on graft survival of living donor kidney transplantation

Living donors have always been the basic resources of transplantation in our country, where cadaveric harvesting is still hampered for various reasons.

OBJECTIVE

The aim of this study was to compare graft survival rates between living unrelated donor (LURD) and living related donor (LRD), to assess the potential risk factors for the graft survival, and to discuss the role of LURD.

METHOD

From October 1991 to February 2003, 77 living donor renal transplants were performed: 41 were LURD and 36 were LRD transplants. The analyzed variables were donor relationship, recipient age and sex, donor age and sex, HLA-DR mismatching, nonspecific blood transfusion history of donor, acute rejection episodes, repeated rejection episode (more than 3 times), delayed graft function, recurred primary disease, and immunosuppressive regimen. Graft survival rate was assessed with the Kaplan-Meier method and the significance of possible variables with the Cox proportional hazard model.

RESULTS

Eleven recipients lost their grafts (6 from LURD and 5 from LRD), most of them are due to chronic rejection (n = 7). Overall 3-, 5- and 10-year graft survival in live donors were 92.8%, 86.6%, and 76.9%, respectively. Graft survival at 3, 5, and 10 years being 91.9%, 88.5%, and 74.7% for the LURD versus 94%, 84%, and 78.8% for LRD transplants (P > .05). Acute rejection episodes, especially more than 3 times (risk ratio [RR] = 11.1) and preoperative multiple transfusion history (RR = 4.2) were significant factors on graft survival in our series.

CONCLUSION

Acute rejection episodes markedly decreased the long-term graft survival in live donor renal transplants. The use of LURD transplants provides graft survival comparable with LRD transplants and proper management to acute rejection is essential for long-term graft survival.

Comparison of survival probabilities for living-unrelated versus cadaveric renal transplant recipients

Any attempt to improve organ donation would be of benefit due to the growing shortage of cadaveric sources for transplantation.

OBJECTIVE

We compared the graft survivals and possible predictive variables among renal transplant recipients with organs from living unrelated (LURD) versus cadaveric donors (CD).

METHOD

Among 104 consecutive renal transplants performed from July 1992 to February 2003, 41 were from LURD and 24 from CD. Immunosuppressive regimens were based on cyclosporine and steroids with mycophenolate mofetil added after 1998. Patient and graft survivals were estimated using the Kaplan-Meier method and compared using log-rank tests. The significance level of predictive variables was analyzed with the Cox proportional hazard model. The follow-up period was 2 to 127 months (median 46 months).

RESULTS

Eight recipients lost their grafts (six from LURD and two from CD) due to four chronic rejections, one acute rejection, one recurrence of primary disease, and one death with a functioning graft. The graft survival rates at 1, 3, 5, and 7 years were 97.6%, 91.9%, 88.5%, and 82.2% for LURD transplants versus 95.5%, 90.9%, 90.9%, and 90.9% for CD transplants, respectively (P > .05). Delayed graft function and donor age (>55 years old) were statistically significant predictors of graft survival among LURD transplants. Donor age (>55 years old) and multiple preoperative transfusion history were significant in CD transplants.

CONCLUSION

LURD transplant survival was similar to that of CD transplants in our series. LURDs are an excellent source of organs to expand the donor pool.

Anaesthesia in patients with Brugada syndrome

Brugada syndrome is characterized by right bundle branch block, ST segment elevation in the precordial leads and sudden death caused by ventricular fibrillation. We present two successful anaesthetic management cases in patients with Brugada syndrome.

Laparoscopic repair of various types of biliary-enteric fistula: three cases

Biliary-enteric fistula is one of the reasons for converting from laparoscopic cholecystectomy (LC) to open surgery. Here we present three cases of various types of biliary-enteric fistula treated successfully by laparoscopic surgery. Two cases were diagnosed preoperatively, and the remaining case intraoperatively. The first patient had a cholecystoduodenal fistula with a common bile duct stone. The second patient had cholecystocolic and choledochoduodenal fistulas with a common bile duct stone, and the third patient had a cholecystogastric fistula. The fistulas were repaired laparoscopically by intracorporeal suturing or with an endoscopic linear stapling device. All the patients had good postoperative courses without any postoperative complication. Our experience has shown us that with advances in surgical skills and instruments, laparoscopic surgery for biliary-enteric fistula can be adopted as the first treatment choice regardless of the preoperative diagnosis.

Expression of cyclooxygenase 2, microsomal prostaglandin E synthase 1, and EP receptors is increased in rat oesophageal squamous cell dysplasia and Barrett's metaplasia induced by duodenal contents reflux

BACKGROUND AND AIM

It is known that bile acids can induce mucosal injury, stimulate cell proliferation, and promote tumorigenesis. A large body of genetic and biochemical evidence indicate that the biosynthetic pathway of prostaglandin E2 (PGE2) may play an important role in human and rodent tumours. Therefore, we examined the expression pattern of cyclooxygenase 1 (COX-1), COX-2, and microsomal prostaglandin E synthase 1 (mPGES-1), as well as EP receptor subtypes in rat oesophageal lesions induced by duodenal contents reflux.

METHODS

Oesophagoduodenal anastomosis was performed in rats to induce duodenal contents reflux. We examined histological changes and expression of COX-1, COX-2, mPGES-1, and EP receptor subtypes in the oesophagus by immunohistochemistry and reverse transcription-polymerase chain reaction.

RESULTS

Normal control oesophageal tissues showed COX-1 expression in subepithelial stromal cells, including endothelial cells and muscular cells, and did not reveal expression of COX-2 or mPGES-1. In the case of squamous cell lesions, immunoreactivity of COX-1 was similar to that of normal lesions, and COX-2 was maximally expressed around the vascular papillae of tissues showing dysplasia and surrounding epithelial layer and basal layer. mPGES-1 was highly expressed in stromal cells with COX-2 expression. In the case of Barrett's oesophagus, COX-2 and mPGES-1 were predominantly in subepithelial stromal cells. mRNA levels of COX-2, mPGES-1, EP2, EP3, and EP4 were higher in the experimental groups than in controls.

CONCLUSIONS

We suggest that the biosynthetic pathway of PGE2 may play an important role in oesophageal squamous cell dysplasia and glandular metaplasia induced by duodenal contents reflux.

Development of the Korean versions of WHO Quality of Life scale and WHOQOL-BREF

The purpose of this study was to develop the Korean version of World Health Organization Quality of Life study assessment instrument (WHOQOL) and WHOQOL-BREF, an abbreviated version of WHOQOL and to identify contributing factors in the quality of life of Koreans. The WHOQOL and WHOQOL-BREF were translated into colloquial Korean according to instructions of the WHOQOL study group. Then the Korean questionnaire was applied to 538 subjects, composed of 171 medical patients and 367 healthy subjects who volunteered to rate the scale. Finally, 486 subjects completed the rating. Collected data were analyzed statistically. The Korean version of WHOQOL and WHOQOL-BREF domain scores demonstrated good test-retest reliability, internal consistency, criterion validity, content validity and discriminant validity. The physical, psychological, social and environmental domains made a significant contribution to explaining the variance in the quality of life while the independence and spiritual domains made a lesser contribution. The domain scores produced by the WHOQOL-BREF correlated highly with the WHOQOL. The physical health domain contributed most in overall quality of life, while the social domain made the least contribution. These results suggest that the Korean version of WHOQOL and WHOQOL-BREF are valid and reliable in the assessment of quality of life and that physical domain is contributing most and social and spiritual factors are contributing least to the quality of life in Koreans.

Effects of transdermal nicotine on attention and memory in healthy elderly non-smokers

RATIONALE

Nicotine has been found to improve cognitive functions in patients with Alzheimer's disease, but little is known about its effects in the healthy non-smoking elderly.

OBJECTIVES

This study aimed to investigate the effects of nicotine on cognitive function in healthy non-smoking or nicotine-naïve elderly subjects.

METHODS

A transdermal patch containing either 5 mg nicotine or placebo was applied on the back of 63 healthy nicotine-naïve or non-smoking elderly Koreans. Cognitive functions were evaluated with the Short Blessed Test, Rey-Kim Memory Test, and digit span test of the Korean-WAIS, both before and 5.5 h after nicotine administration. The plasma level of nicotine after testing was measured using gas chromatography.

RESULTS

The subjects' memory functions in trial 5 of the Rey-Kim Memory Tests improved significantly. Furthermore, the effect on memory slope was significantly correlated with the higher plasma level of nicotine. However, the other tests did not reveal any correlation to a significant degree.

CONCLUSIONS

These results suggest that nicotine of lower plasma level can improve short-term verbal memory functions in non-smoking or nicotine-naïve healthy elderly people and that some effects are dependent on nicotine plasma levels.

[Genetic study of plant height of tall plant mutant Mh-1 in rice (Oryza sativa L.)]

Mh-1 is a tall plant mutant induced by irradiation from semi-dwarfed variety Guichao 2. The genetic analyses were carried out through the F1, F2, F3 progenies and test-crossed F1 on Mh-1 crossed with materials with sd-1 gene, non-allelic gene to sd-1 and common tall plant. The results indicate that the induced tall plant trait of Mh-1 is controlled by a recessive inhibiting gene, named tentatively i-sd-1(t), that can regulate the expression of sd-1 gene but not of non-allelic gene to sd-1. The valuation of i-sd-1(t) in hybrid rice breeding was discussed.

Role of lipid peroxidation and poly(ADP-ribose) polymerase activation in oxidant-induced membrane transport dysfunction in opossum kidney cells

This study was undertaken to examine the role of lipid peroxidation and poly(ADP-ribose) polymerase (PARP) activation in H(2)O(2)-induced inhibition of Na(+)-dependent phosphate (Na(+)-Pi) uptake in opossum kidney (OK) cells. H(2)O(2) inhibited Na(+)-Pi uptake in a dose-dependent manner. H(2)O(2)-induced inhibition of Na(+)-Pi uptake was prevented by dithiothreitol and glutathione. A potent antioxidant, DPPD, had no effect on H(2)O(2) inhibition of Na(+)-Pi uptake, despite completely inhibiting lipid peroxidation induced by H(2)O(2). However, in primary cultured rabbit proximal tubular cells, the effect of H(2)O(2) on Na(+)-Pi uptake was significantly prevented by DPPD, suggesting a species difference in the role of lipid peroxidation in the inhibition of Na(+)-Pi uptake occurring with H(2)O(2). t-Butylhydroperoxide (tBHP) caused the inhibition of Na(+)-Pi uptake that was prevented by DPPD in OK cells and rabbit proximal tubular cells. The PARP inhibitor 3-aminobenzamide completely protected the inhibition of Na(+)-Pi uptake induced by H(2)O(2) but not by tBHP. H(2)O(2)-induced ATP depletion was prevented by 3-aminobenzamide but not by DPPD. tBHP-induced ATP depletion was prevented by DPPD, whereas it was not altered by 3-aminobenzamide. Effects of H(2)O(2) and tBHP on Na(+)-Pi uptake and ATP depletion were prevented by an iron chelator, deferoxamine, suggesting that the oxidants inhibit Na(+)-Pi uptake through an iron-dependent mechanism. The extent of DNA damage by tBHP was similar to that by H(2)O(2). These results indicate that the effect of H(2)O(2) on membrane transport function in OK cells is associated with PARP activation but not lipid peroxidation, whereas the effect of tBHP is associated with lipid peroxidation.

Positive and negative symptoms and regional cerebral perfusion in antipsychotic-naive schizophrenic patients: a high-resolution SPECT study

In 17 antipsychotic-naive schizophrenic patients, the scores of positive and negative symptoms of schizophrenia were correlated with relative regional cerebral perfusion measured by 99m-Tc-ECD (ethyl cysteinate dimer) single photon emission computed tomography (SPECT). Scans were performed in subjects at rest. The negative symptom dimension was significantly correlated with a decreased level of perfusion in the left thalamic region. Other non-significant trends were also observed; the positive symptom dimension was related to decreased perfusion in the left temporal region and to increased perfusion in the right frontal region, while the negative symptom dimension was related to increased perfusion in the left frontal region. These findings suggest that the positive and negative symptoms of schizophrenia are related to dysfunctions in different regions of the brain and different lateralized patterns of dysfunction.

[Genetic analysis on a new sterile locus discovered in hybrids between indica and japonica rice (Oryza sativa L.)]

Japonica line 02428, possessing wide compatibility gene S-5n, showed semi-sterility as crossed with indica variety IR24. Genetic analysis was conducted on the spikelet fertility in segregation generations from the crosses of 02428 with IR24, Pecos and Akihikara. The results indicated that the sterility in hybrids between 02428 and IR24 was controlled by a single non-allelic to S-5 gene and its inheritance fitted to one-locus sporo-gametophytic interaction model. Pecos, an American variety, has a neutral allele. The new sterility locus was preliminarily located near G24 marker on chromosome 11 detected by RFLP. The non-allelic S-locus in the study is named tentatively S-p(t). It was found that the sterility caused by the cross of Akihikara and IR24 was controlled by two S-loci, S-5 and S-p(t), and its genetical effect was additive.

Inhibition of stress-induced plasma corticosterone levels by ginsenosides in mice: involvement of nitric oxide

Ginseng total saponins (GTS) injected intracerebroventricularly (i.c.v.) at doses of 0.1-1 microg inhibited the i.c.v. injection stress-induced plasma corticosterone levels in mice. The inhibitory action of GTS was blocked by co-administered N(G)-nitro-L-arginine methyl ester (L-NAME; 1.5 microg, i.c.v.), an inhibitor of nitric oxide synthase (NOS). Of the ginsenosides Rb1, Rb2, Rc, Rd, Re, Rf, Rg1, 20(S)-Rg3 and 20(R)-Rg3 injected i.c.v. at doses of 0.01-1 microg, 20(S)-Rg3 and Rc significantly inhibited the i.c.v. injection stress-induced plasma corticosterone levels. The inhibitory actions of 20(S)-Rg3 and Rc were blocked by co-administered L-NAME (1.5 microg, i.c.v.). These results suggest that GTS, 20(S)-Rg3 and Rc may inhibit the i.c.v. injection stress-induced hypothalamo-pituitary-adrenal response by inducing NO production in the brain.

Laterality in somatization

OBJECTIVE

To identify whether there is a lateralized pattern in somatic symptoms related to emotional disturbances.

METHOD

Sixty-one patients with depressive disorders, anxiety disorders, and somatization disorders were examined for the lateralized distribution of somatic symptoms in the body and its relationship to the severity of anxiety and depression.

RESULTS

The chief somatic symptoms presented significantly more on the left side than on the right side of the body. Headache and other forms of pain, especially, occurred more on the left side. There was no significant difference between left-sided and right-sided groups in demographic variables such as age, gender, marital status, education level, diagnosis, and duration of illness. The scores on Hamilton's anxiety scale or Hamilton's depression scale were higher in the left-sided group than the right-sided group, although the difference was not statistically significant.

CONCLUSIONS

These results suggest that the right hemisphere of the brain is more involved then the left with somatization symptom formation related to emotional disturbances.

RFLP mapping of QTLs for yield and related characters in rice (Oryza sativa L.)

Quantitative triat loci (QTLs) for yield and related traits in rice were mapped based on RFLP maps from two indica/indica F2 populations, Tesanai 2/CB and Waiyin 2/CB. In Tesanai 2/CB, 14 intervals carrying QTLs for eight traits were detected, including 3 for grain weight per plant (GWT), 2 for number of panicles per plant (NP), 2 for number of grains per panicle (NG), 1 for total number of spikelets per panicle (TNS), 1 for spikelet fertility (SF), 3 for 1000-grain weight (TGWT), 1 for spikelet density (SD), and 1 for number of first branches per main panicle. The 3 QTLs for GWT were located on chromosomes 1, 2, and 4, with 1 in each chromosome. The additive effect of the single locus ranged from 2.0 g to 9.1 g. A major gene (np4) for NP was detected on chromosome 4 within the interval of RG143-RG214, about 4cM for RG143, and this locus explained 26.1% of the observed phenotypic variance for NP. The paternal allele of this locus was responsible for reduced panicles per plant (3 panicles per plant). In another population, Waiyin 2/CB, 12 intervals containing QTLs for six of the above-mentioned traits were detected, including 3 for GWT, 2 for each of NP, TNS, TGWT and SD, 1 for SF. Three QTLs for GWT were located on chromosome 1, 4, and 5, respectively. The additive effect of the single locus for GWT ranged from 6.7 g to 8.8 g, while the dominance effect was 1.7-11.5 g. QTL mapping in two populations with a common male parent is compared and discussed.

Flow cytometric DNA analysis of gastric cancer--correlation with histology and clinical outcome

Nuclear DNA content was analysed by means of flow cytometric measurements in 103 patients with gastric carcinomas, using paraffin-embedded archival tissue. DNA aneuploidy was found in 40 cases (38.8%). The mean DNA index of aneuploid tumors was 1.45(range 1.13 to 2.37). No significant association between ploidy and either age, sex, tumor location, size, stage, growth pattern, or histologic type was found. However, the incidence of aneuploidy was higher in high grade carcinomas than in low grade carcinomas; the incidence of aneuploidy was 10%, 68.8%, and 45.8% for Grade II, III, and IV carcinomas, respectively, as compared with Grade I carcinomas which were all diploid. On statistical analysis, Abnormal cellular DNA content was significantly correlated with high histologic grade (P < 0.005). Patients with aneuploid cancer (39.2%) had a poorer prognosis than those with diploid cancer (70.0%) based on (P < 0.01). The 2-year survival rate for advanced gastric carcinoma. Therefore, DNA ploidy might be a useful prognostic factor in cases of advanced gastric cancer.

Risperidone versus haloperidol in the treatment of chronic schizophrenic patients: a parallel group double-blind comparative trial

A parallel group double-blind comparative trial was conducted to study the efficacy and safety of risperidone compared with haloperidol. After a one-week wash-out, 35 chronic schizophrenic patients (17 males, 18 females) were randomly assigned to one of two groups for eight weeks of double-blind treatment. The patients' psychopathology was assessed by means of the Positive and Negative Syndrome Scale for Schizophrenia (PANSS) and the Clinical Global Impression (CGI). Safety assessments included the Extrapyramidal Symptom Rating Scale (ESRS), the UKU Side Effect Rating Scale, vital signs, body weight, ECG and laboratory screening. Thirty-two patients completed the trial: there were 3 dropouts in the risperidone group. The results on the PANSS and CGI indicate that the mean changes from baseline on the total PANSS score and on the total BPRS score were comparable in both treatment groups. The number of patients where a clinical improvement at least 20% reduction in baseline score was also similar in both treatment groups. Risperidone caused less extrapyramidal symptoms and less side effects in UKU scale than haloperidol. No significant ECG changes were induced, no relevant changes in blood pressure or clinical laboratory parameters were observed. This study has demonstrated that the combined serotonin 5-HT2 and dopamine-D2 antagonist risperidone is an antipsychotic as potent as haloperidol. Risperidone causes less extrapyramidal symptoms, and is better tolerated than haloperidol.

Modification of atracurium or vecuronium blockade and their reversal by succinylcholine in the cat

The interaction between succinylcholine (SCC) and non-depolarizers, atracurium or vecuronium was investigated in 36 cats of either sex using the sciatic nerve-anterior tibialis muscle preparation. Additionally, the relation of SCC to pseudocholinesterase activity was examined. The duration of action of vecuronium (6.5 +/- 1.3 to 7.3 +/- 2.2 minutes) in cats pretreated with SCC was greater than those (2.0 +/- 0.6 minutes) in non-pretreated cats. However, SCC had no influence on the duration of atracurium. The serum pseudocholinesterase activity was decreased after the injection of atracurium or neostigmine in contrast to vecuronium. The authors conclude that the prior administration of SCC prolongs the duration of vecuronium but not that of atracurium, and pseudocholinesterase activity is not related to the prolonging effect of SCC.

Hemispheric asymmetry in visual recognition of words and motor response in schizophrenic and depressive patients

Two-letter Hangul words were presented tachistoscopically as target words to either the right or left visual field of normal subjects, schizophrenics, and depressive patients. The subjects' task was to judge the similarity or difference between the target words and the words used for comparison. They were to signal as soon as possible by pressing a key with their hands. In normal subjects, the correct response rate was significantly higher in the left hemisphere; there was little difference in the speed of motor response between the two hemispheres, however. Compared with normal subjects, both patient groups showed generalized impairment. Schizophrenia was associated with impairment in the left hemisphere, depression was associated with impairment in the right hemisphere.

Tourette disorder and HLA typing

HLA A, B, C and DR were typed in 73 Korean patients with Tourette disorder meeting the diagnostic criteria of DSM III-R and compared with 291 normal subjects. Relatively higher frequencies were found in HLA A11 and A26(10) with lower incidences in HLA A24(9) and B13. A family history of tic disorders was associated with a lower frequency of HLA A24(9).

Comparative study of affective disorders in three Asian countries. II. Differences in prevalence rates and symptom presentation

This study used standardized diagnostic criteria and method to investigate both prevalence rates and nature of symptoms of depressive disorders in three Asian centres--Nagasaki, Shanghai and Seoul. Of the patients who visited a psychiatric clinic in each of the 3 centres for the first time, over 20% suffered from depression. Unlike previous reported prevalence rates for Asian countries, these results suggest that rates in Asia may not be much lower than those reported in Western countries. Although prevalence rates of depression were similar in all 3 centres, differences in symptoms were noted.

Comparative study of affective disorders in three Asian countries. I. Differences in diagnostic classification

A study aimed at the standardization of symptom evaluation of patients with depression was carried out as the first step in an extensive collaborative study on affective disorders between centers in Nagasaki, Shanghai and Seoul. This study was initiated in order to clarify the factors affecting the low reported prevalence rates of depressive disorders in Asia. No significant difference in evaluation of psychiatric symptoms was observed between the 3 centers. Nevertheless, the diagnoses given by ICD-9 showed very interesting differences. For any given case, Nagasaki tended to make a diagnosis of an affective psychosis depression, while Shanghai made a diagnosis of neurotic disorder. No significant tendency was observed in the Seoul center. These findings are discussed in terms of their importance for future international collaborative studies.