Postoperative pulmonary vascular growth in patients with congenital diaphragmatic hernia

BACKGROUND

Postoperative pulmonary growth in congenital diaphragmatic hernias (CDH) remains unclear. We investigated postoperative pulmonary vascular growth using serial lung perfusion scintigraphy in patients with CDH.

METHODS

Neonates with left CDH who underwent surgery and postoperative lung perfusion scintigraphy at our institution between 2001 and 2020 were included. Patient demographics, clinical courses, and lung scintigraphy data were retrospectively analyzed by reviewing medical records.

RESULTS

Twenty-one patients with CDH were included. Of these, 10 underwent serial lung scintigraphy. The ipsilateral perfusion rate and median age on the 1st and serial lung scintigraphy were 32% (34 days) and 33% (3.6 years), respectively. Gestational age at prenatal diagnosis (p = 0.02), alveolar-arterial oxygen difference (A-aDO2) at birth (p = 0.007), and preoperative nitric oxide (NO) use (p = 0.014) significantly correlated with the 1st lung scintigraphy. No other variables, including operative approach, were significantly correlated with the 1st or serial scintigraphy findings. All patients improved lung perfusion with serial studies [Difference:  + 7.0 (4.3-13.25) %, p = 0.001, paired t-test]. This improvement was not significantly correlated with preoperative A-aDO2 (p = 0.96), NO use (p = 0.28), or liver up (p = 0.90). The difference was significantly larger in patients who underwent thoracoscopic repair than in those who underwent open abdominal repair [+ 10.6 (5.0-17.1) % vs. + 4.25 (1.2-7.9) %, p = 0.042].

CONCLUSION

Our study indicated a postoperative improvement in ipsilateral lung vascular growth, which is possibly enhanced by a minimally invasive approach, in patients with CDH.

The importance of designing a protector for a preterm and low birth weight infant with ectopia cordis

Ectopia cordis is a rare condition with expected low survival rate based on past studies. We encountered a case of a preterm and low birth weight infant with ectopia cordis. When the infant cried, the prolapse of the heart, liver, and intestinal tract worsened. A pressure-applying protector was used to protect the organs and reduce the prolapse. Upon application, the infant's tachypnea and desaturation worsened. Fluoroscopic examination suggested that the pressure from the prolapsed regions was impeding pulmonary expansion and negatively affecting circulation. It is essential to carefully design a protector that accommodates the infant's growth.

Design and validation of looping assistance methods in robotic-assisted neonatal surgical suturing in a chest model

BACKGROUND

Neonate patients have a reduced thoracic cavity, making thoracoscopic procedures even more challenging than their adult counterparts.

METHODS

We evaluated five control strategies for robot-assisted thoracoscopic surgical looping in simulations and experiments with a physical robotic system in a neonate surgical phantom. The strategies are composed of state-of-the-art constrained optimization and a novel looping force feedback term.

RESULTS

All control strategies allowed users to successfully perform looping. A user study in simulation showed that the proposed strategy was superior in terms of Physical demand p < 0.05 $\left(p< 0.05\right)$ and task duration p < 0.05 $\left(p< 0.05\right)$ . The cumulative sum analysis of inexperienced users shows that the proposed looping force feedback can speed up the learning. Results with surgeons did not show a significant difference among control strategies.

CONCLUSIONS

Assistive strategies in looping show promise and further work is needed to extend these benefits to other subtasks in robot-aided surgical suturing.

A case of Hirschsprung's disease with segmental dilatation of the colon

BACKGROUND

Segmental dilatation of the colon (SDC) is a rare disease that is characterized by an abrupt segment of dilated colon between regions of normal-sized colon. We herein report a case of SDC associated with Hirschsprung's disease (HD).

CASE PRESENTATION

The patient developed abdominal distension soon after birth, and enema examination showed localized intestinal dilatation from the descending colon to the sigmoid colon with significant caliber changes on both the oral and anal sides of the dilated colon. The findings of the rectal mucosal biopsy were consistent with HD. We considered this case to be a combination of HD and SDC and performed laparoscopic-assisted Soave pull-through with resection of the dilated colon when the patient was 7 months old. Resected specimens showed steep caliber changes on the oral and anal sides of the dilated colon. In the pathological examination, no ganglion cells were found in the submucosa on the anal side of the dilated colon. Based on the above findings, we finally made the diagnosis of HD with SDC.

CONCLUSION

In HD with a characteristic dilated colon, the possibility of SDC should be considered.

Examination of the effectiveness of bedside nasojejunal tube placement using a portable imaging device with a flat panel detector

Transporting pediatric patients with severe cardiovascular complications to the fluoroscopy room can be difficult. Therefore, we started using a portable imaging device with a flat panel detector (FPD) for nasojejunal tube (NJT) placement. The purpose of this study was to investigate the differences in length of time of NJT placement and dosage of radiation exposure using a portable imaging device with FPD versus fluoroscopy. Pediatric patients who underwent NJT placement between April 2016 and December 2018 were identified retrospectively from the clinical records. The age, sex, body weight, and height of each child at the time of the procedure as well as the procedure time, outcomes of the procedure, and dosage of radiation exposure was compared between the two groups. In 76 cases of NJT placement (41 patients), there was no significant difference in the success rate of NJT placement between the FPD (90%) and fluoroscopy groups (95%). However, the NJT placement time was significantly longer in the FPD group than in the fluoroscopy group (488 s vs 291 s). According to our calculations, the radiation dosage was lower in the FPD group than in the fluoroscopy group (136 μGy per procedure vs 2819 μGy per procedure). These results suggest that NJT placement using a portable imaging device with an FPD can be an effective method for children who are difficult to transport with an equal success rate and lower dosage of radiation exposure compared with conventional fluoroscopy.

Discovery of Candidate Stool Biomarker Proteins for Biliary Atresia Using Proteome Analysis by Data-Independent Acquisition Mass Spectrometry

Biliary atresia (BA) is a destructive inflammatory obliterative cholangiopathy of the neonate that affects various parts of the bile duct. If early diagnosis followed by Kasai portoenterostomy is not performed, progressive liver cirrhosis frequently leads to liver transplantation in the early stage of life. Therefore, prompt diagnosis is necessary for the rescue of BA patients. However, the prompt diagnosis of BA remains challenging because specific and reliable biomarkers for BA are currently unavailable. In this study, we discovered potential biomarkers for BA using deep proteome analysis by data-independent acquisition mass spectrometry (DIA–MS). Four patients with BA and three patients with neonatal cholestasis of other etiologies (non-BA) were recruited for stool proteome analysis. Among the 2110 host-derived proteins detected in their stools, 49 proteins were significantly higher in patients with BA and 54 proteins were significantly lower. These varying stool protein levels in infants with BA can provide potential biomarkers for BA. As demonstrated in this study, the deep proteome analysis of stools has great potential not only in detecting new stool biomarkers for BA but also in elucidating the pathophysiology of BA and other pediatric diseases, especially in the field of pediatric gastroenterology.

Optimal Viewing Direction of the Oblique Laparoscope in Single-Incision Laparoscopic Percutaneous Extraperitoneal Closure for Inguinal Hernia

Background: It is difficult for novice surgeons to manipulate the oblique laparoscope in single-incision laparoscopic percutaneous extraperitoneal closure (SILPEC) for inguinal hernia because of collisions between the instruments. To standardize manipulation of the laparoscope, we studied the viewing direction of the oblique laparoscope, and assessed the optimal manipulation of the laparoscope to avoid collisions. Methods: A retrospective chart review was performed on patients who underwent SILPEC between April 2016 and April 2017. The viewing direction of the 30° oblique laparoscope was measured according to the location of the field stop pointer. Patients were divided into three groups according to the viewing direction at the beginning of the procedure: the inside viewing direction was from -90° to -11°, upward viewing direction was from -10° to 10°, and outside viewing direction was from 11° to 90°. The length of the procedure, viewing direction at the end, and the percentage of cases in which there was a change in viewing direction during the procedure were compared. Results: Ninety-eight cases of SILPEC were performed during the study period. The percentage of patients with a change in category of viewing direction in the inside, upward, and outside groups was 35%, 21%, and 11%, respectively, showing a significant difference among the three groups. Conclusions: Setting the initial viewing direction to the outside can reduce correction of the viewing direction during SILPEC. Because the intersection angle between the outside-viewing laparoscope and forceps is close to a right angle, this might reduce collisions.

A large superior mesenteric artery aneurysm and ileal obstruction: a rare presentation of polyarteritis nodosa in an infant

Polyarteritis nodosa (PAN) is a rare form of vasculitis that occurs in childhood and affects small- and medium-sized arteries. Large aneurysms due to PAN can induce fatal complications like rupturing or occlusion of the affected arteries. Here, we report a case of a 4-month-old girl with PAN complicated by a large superior mesenteric artery aneurysm and ileal obstruction. We controlled her blood pressure to prevent the artery from rupturing. A combination of prednisolone, intravenous cyclophosphamide, and plasma exchange reduced the inflammation. She developed mechanical ileus due to ileum stricture and underwent bowel resection. Histopathological examinations revealed reparative arteritis around the healed ulcer. Her postoperative course was uneventful without further dilatation of the aneurysm. This case highlights the importance of intensive immunosuppressive therapy and appropriate blood pressure control in pediatric patients with PAN complicated by large aneurysms. Mechanical ileus can develop and may require surgical management even after remission of vasculitis.

Evaluation of Surgical Devices Using an Artificial Pediatric Thoracic Model: A Comparison Between Robot-Assisted Thoracoscopic Suturing Versus Conventional Video-Assisted Thoracoscopic Suturing

BACKGROUND

Pediatric robot-assisted surgery is increasingly being performed, but it is difficult to perform this procedure in infants. A pediatric thoracoscopic model of a 1-year-old patient was developed in our previous study, and this model was used to evaluate the use of a surgical robot for infant surgery.

METHODS

Eight pediatric surgeons performed an intracorporeal suturing and knot-tying task using the da Vinci Xi Robotic Surgical System. The task completion time, number of needle manipulations, and force applied during suturing of the robot-assisted thoracoscopic surgery (RATS) group were compared with those of the video-assisted thoracoscopic surgery (VATS) group whose data had been collected from the same 8 surgeons in our previous study.

RESULTS

The RATS group showed a significantly shorter completion time than the VATS group in the knot-tying phase (P = .016) and in the total phase (P = .0078). The RATS group showed a significantly smaller number of manipulations than the VATS group in the total phase (P = .039). The RATS group showed a significantly smaller pushing force index than the VATS group in the suturing phase (P = .031), knot-tying phase (P = .031), and in the total phase (P = .031). A seventh rib in the model was dislocated in all RATS group cases.

CONCLUSIONS

The da Vinci Surgical System might be useful in infants because of fast movement and small pushing force. However, the robotic 8 mm instruments were too large for use in the thoracic cavity of the 1-year-old infant.

More than one-third of successfully nonoperatively treated patients with complicated appendicitis experienced recurrent appendicitis: Is interval appendectomy necessary?

BACKGROUND

Although nonoperative treatment (non-OPT) for complicated appendicitis is performed widely, the long-term outcomes and merits of interval appendectomy (IA) need to be evaluated.

METHODS

Between April 2007 and December 2013, all appendicitis patients with well-circumscribed abscess or phlegmon were required to select either laparoscopic surgery (OPT) or non-OPT with optional IA on admission. Optional IA was planned at ≥3months after non-OPT. For non-OPT, intravenous injection of antibiotics was continued until the serum C-reactive protein concentration decreased to <0.5mg/dL, with occasional drainage of abscesses.

RESULTS

Thirty-three patients chose OPT, and 55 chose non-OPT. Among non-OPT patients, 16 selected IA. The success rate of non-OPT was 98.2%. Recurrence occurred in 13 (34.2%) of the 38 non-IA group patients. Although the non-IA group patients frequently had perforated appendicitis at recurrence, they visited the hospital earlier than at the initial appendicitis and had less inflammation. Readmission rate or complications in patients undergoing IA were not different compared with those of the patients in the non-IA group, who had recurrence at ≥3months, or with those of patients in the OPT group.

CONCLUSION

Although many patients experienced recurrent appendicitis after successful nonoperative treatment, IA may not be necessary after non-OPT.

LEVEL OF EVIDENCE

Prospective comparative study, level II.

A multi-degree-of-freedom needle driver with a short tip and small shaft for pediatric laparoscopic surgery: in vivo assessment of multi-directional suturing on the vertical plane of the liver in rabbits

BACKGROUND

Laparoscopic Kasai portoenterostomy has been performed in infants with biliary atresia at several institutions, but laparoscopic anastomosis requiring multi-directional suturing on a vertical plane of the liver remains a challenge. To assist multi-directional suturing, we developed a multi-degree-of-freedom (DOF) needle driver whose tip length was 15 mm and shaft diameter was 3.5 mm. The tip of the multi-DOF needle driver has three DOFs for grasp, flection and rotation. The aim of this study was to evaluate the performance of the multi-DOF needle driver in two kinds of in vivo experiments.

METHODS

Surgeons were asked to perform four-directional laparoscopic suturing on a vertical plane of the liver in six rabbits using the multi-DOF needle driver or a conventional needle driver. The needle grasping time, the needle handling time, the number of needle insertions, the number of liver lacerations, the suturing width and depth, and the area of necrotic tissues were analyzed and compared. Additionally, one surgeon was asked to perform laparoscopic hepato-jejunostomy in four rabbits to assess the feasibility of Kasai portoenterostomy using the multi-DOF needle driver.

RESULTS

The suturing depth using the multi-DOF needle driver was significantly larger than that using the conventional needle driver in both the right and downward suturing directions. No statistically significant differences were found in other metrics. Liver lacerations were observed only when suturing was performed using the conventional needle driver. The experimental laparoscopic hepato-jejunostomy using the multi-DOF needle driver was successful.

CONCLUSIONS

Using the multi-DOF needle driver, uniform multi-directional suturing on a vertical plane of the liver could be performed. The short distal tip of the multi-DOF needle driver demonstrated its advantages in multi-directional suturing in a small body cavity. The multi-DOF needle driver may be able to be used to perform complex tasks in laparoscopic Kasai portoenterostomy.

Influence of surgical intervention on neurodevelopmental outcome in infants with focal intestinal perforation

BACKGROUND

Intestinal perforation is known to correlate with neurodevelopmental outcome in very low-birthweight (VLBW) infants, and its two major causes are necrotizing enterocolitis (NEC) and focal intestinal perforation (FIP). Infants with FIP are reported to have better neurodevelopmental outcome than infants with NEC, but outcome has not been compared with that in infants without diseases that require surgery. The aim of this study was to compare neurodevelopmental outcomes between FIP survivors and infants without diseases that require surgery.

METHODS

Records of VLBW infants with FIP and infants without surgical diseases were retrospectively analyzed. Neurodevelopmental outcome was compared between eight infants with FIP and 24 case-matched control infants without surgical diseases using the Kyoto Scale of Psychological Development. Control group members were individually matched with FIP survivors for sex, gestational age, birthweight, and intraventricular hemorrhage (IVH) grade. Those with an episode of sepsis or severe IVH (grade 3-4) that occurred irrespective of FIP were excluded.

RESULTS

Three FIP survivors and 12 infants without surgical diseases were classified as neurodevelopmentally normal (37.5% vs 50%, P = 0.69) at a corrected age of 18 months-3 years. All neurodevelopmentally normal FIP survivors were born at a gestational age ≥ 26 weeks.

CONCLUSION

Excluding the influence of sepsis or severe IVH, no significant difference was found in neurodevelopmental outcome between FIP survivors and infants without surgical diseases. None of the FIP infants born before 26 weeks of gestation, however, had normal neurodevelopment, suggesting that longer gestation might be needed to overcome the stress associated with FIP.

Video-based skill assessment of endoscopic suturing in a pediatric chest model and a box trainer

PURPOSE

Pediatric endoscopic surgery requires special surgical skills because of the small working space and tissue fragility. This article presents a video-based skill assessment method for endoscopic suturing using a pediatric chest model.

MATERIALS AND METHODS

A commercial suture pad was placed in a rapid-prototyped pediatric chest model of a 1-year-old patient to simulate the thoracoscopic repair of esophageal atresia type C. Twenty-eight pediatric surgeons (9 experts, 9 intermediates, and 10 trainees) performed an endoscopic intracorporeal suturing and knot-tying task both in the pediatric chest model and in a box trainer. The tasks were video-recorded and rated by two blinded observers using the 29-point checklist method and a suturing errors score sheet method. The task completion time and the number of needle manipulations were measured.

RESULTS

The expert group showed better performance than the intermediate and trainee groups in the pediatric chest model, and the differences were larger than those in the box trainer. Significant differences between the expert and the trainee groups were observed in the items related to safety such as the skills for keeping the needle in view at all times. Significant differences between the expert and intermediate groups were observed in the items related to task quality and efficiency such as the smoothness of knot tying and the number of needle manipulations.

CONCLUSIONS

Video-based skill assessment of endoscopic suturing using the pediatric chest model and a box trainer distinguished pediatric endoscopic surgeons according to their clinical experience, and pediatric-specific skills were identified.

Laparoscopic partial nephrectomy for the treatment of large cystic nephroma in children

Abstract Background: Cystic nephroma (CN) is a rare benign renal neoplasm. The differential diagnosis of cystic partially differentiated nephroblastoma is only possible with pathological findings. Therefore, surgical resection is necessary to diagnose suspected CN lesions. Because CN is usually well demarcated and has a good prognosis, partial nephrectomy is recommended for its treatment. However, to our knowledge, laparoscopic treatment of CN has not been reported. We describe 2 cases of large CNs successfully treated: Case 1 was a 9-month-old boy with a lower polar mass in the right kidney, which occupied two-thirds of the kidney, and Case 2 was a 9-month-old boy with an upper polar mass in the left kidney, which occupied three-fourths of the kidney.

MATERIALS AND METHODS

Using the transperitoneal approach, the lesion was detected by a laparoscopic ultrasound probe, and vessels in the affected region were dissected. After the renal artery was clamped with bulldog clips, the parenchyma of the affected region was divided with an ultrasonically activated scalpel. The partly cut pelvis was closed by suturing, and the resected stump was coated with hemostatic agents and covered with the pediculate peritoneum.

RESULTS

The lesion was not exposed during surgery, and the microscopic features were consistent with CN in both cases. Residual renal function was good, and no residual tumor was found in both cases for over a year.

CONCLUSIONS

Laparoscopic partial nephrectomy is a feasible approach to treat large CNs. When it is difficult to close the resection stump by parenchymal suturing, covering the stump with hemostatic agents and pediculate peritoneum is feasible.

Development of new devices for translumenal endoscopic esophageal anastomosis

AIM

This study aimed to develop new devices for translumenal endoscopic esophageal anastomosis-a stent and a ligating device-and to confirm the feasibility of our novel procedure using those devices.

MATERIALS AND METHODS

We designed a ligating device as an overtube whose tip worked like the EVL device (Sumitomo Bakelite Co. Ltd., Tokyo, Japan). The newly developed procedure for anastomosis is as follows: a silicone elastic band, which was released from the device located at the upper esophagus, and a custom-made expandable stent, which was expanded by the balloon catheter in the lower esophagus, tightened the upper and lower esophageal walls. After producing the devices, we performed the anastomosis procedure in porcine models.

RESULTS

A ligating device and an expandable stent were developed for this study. An ex vivo feasibility study was performed in three porcine models. Endoscopic visualization revealed that all steps in this procedure were technically successful. The median time needed to perform this procedure was 24 (range, 19-25) minutes. Patency of the anastomosis was confirmed in all specimens.

CONCLUSIONS

Translumenal esophagoesophageal anastomosis using the new devices was feasible. The procedure time was sufficiently short for clinical use. An in vivo survival study is needed to confirm the safety and reliability of this procedure.

External stabilization for severe tracheobronchomalacia using separated ring-reinforced ePTFE grafts is effective and safe on a long-term basis

PURPOSE

Tracheobronchomalacia is a respiratory disorder that results from abnormal cartilage development. Since 2003, we have performed external stabilization for severe tracheobronchomalacia using separated ring-reinforced expanded polytetrafluoroethylene (ePTFE) grafts. The aim of this study was to analyze the short- and long-term outcomes of our procedure.

METHODS

We reviewed the charts of patients who underwent external tracheobronchial stabilization from January 2003 through December 2012. Separated ring-reinforced ePTFE grafts were fixed to the anterior and posterior lesions of malacia independently, with confirmation of a well-opened lumen by bronchoscopy.

RESULTS

Five children with severe tracheobronchomalacia underwent six operations. The median follow-up period was 43 months (range 11-109 months). There was no operative mortality associated with the procedure. One patient required removal of a section of the graft owing to the development of bronchial granulation tissue at the site of fixation. All patients showed improved respiratory function, and tracheal growth was confirmed by follow-up computed tomography.

CONCLUSIONS

External stabilization with separated ring-reinforced ePTFE grafts for severe tracheobronchomalacia is effective, less invasive than alternatives and preserves the growth potential of the affected airway segment.

Development of a needle driver with multiple degrees of freedom for neonatal laparoscopic surgery

AIMS

The aims of this study were to develop a thin needle driver with multiple degrees of freedom and to evaluate its efficacy in multidirectional suturing compared with a conventional needle driver.

MATERIALS AND METHODS

The tip (15 mm) of the novel user-friendly needle driver (3.5 mm in diameter) has three degrees of freedom for grasping, rotation, and deflection. Six pediatric surgeons performed two kinds of suturing tasks in a dry box: three stitches in continuous suturing that were perpendicular or parallel to the insertion direction of the instrument, first using the novel instrument, then using a conventional instrument, and finally using the novel instrument again. The accuracy of insertion and exit compared with the target points and the procedure time were measured.

RESULTS

In the conventional and novel procedures the mean gaps from the insertion point to the target in perpendicular suturing were 0.8 mm and 0.7 mm, respectively; in parallel suturing they were 0.8 mm and 0.6 mm, respectively. The mean gaps from the exit point to the target in perpendicular suturing were 0.6 mm and 0.6 mm for conventional and novel procedures, respectively; in parallel suturing they were 0.6 mm and 0.8 mm, respectively. The procedure time for perpendicular suturing was 33 seconds and 64 seconds for conventional and novel procedures, respectively (P=.02); for parallel suturing it was 114 seconds and 91 seconds, respectively.

CONCLUSIONS

Our novel needle driver maintained accuracy of suturing; parallel suturing with the novel driver may be easier than with the conventional one.

A topographical study of ERP correlates of semantic and syntactic violations in the Japanese language using the multichannel EEG system

Language processing was investigated using event-related potentials obtained using a multichannel (58-channel) EEG system, with regard to semantic dependency (i.e., selectional restriction between a verb and the arguments it takes: the SR type) and syntactic dependency between sentence-final particles and interrogative phrases (the WH-Q type) in Japanese. It was found that semantic violations elicited the conventional N400, which was distributed in the bilateral occipital and the right temporal regions, and that the syntactic violations elicited the P600 in a broad area, predominantly in the centroparietal regions. Scalp current density mappings suggested that the right temporal cortex plays a significant role in integrating pieces of contextual information, especially when it is difficult to integrate a word in the context of a sentence, and that the P600 was connected to the syntactic processes conceivably indexed by the left temporal current sink with a relatively early onset.

Comparison of the effects of zolpidem and triazolam on nocturnal sleep and sleep latency in the morning: a cross-over study in healthy young volunteers

1. Zolpidem (ZPD, 10 mg) was directly compared with triazolam (TRZ, 0.25 mg), a benzodiazepine hypnotic of a short action comparable to ZPD. The compounds were given to healthy young subjects for three nights, in a crossover design. 2. Polysomnographic data of three 150-min sections of the nights as well as the whole nights were analyzed, to clearly detect the proper effects of the very short acting hypnotics, which might be missed in the analysis of whole night. 3. Time courses were significantly different between the two compounds in the ratios (%) of stage wake (SW), stage 2 (S2), slow wave sleep (SWS) and stage REM (SR). 4. Compared to the baseline, SWS was increased by ZPD on the first night, not by TRZ. The separate analysis of the three 150-min sections revealed an increase of SWS during the first 150-min of the ZPD night, suggesting a proper action of ZPD to augment SWS. An increase of S2 and a decrease of SR were caused by TRZ, not by ZPD. However, the separate analysis indicated that ZPD might reduce SR during the first 150-min, which was cancelled by a subsequent rebound increase in the whole night analysis. 5. During the withdrawal period, TRZ, not ZPD, increased SW and SR with worsening of mood in the morning. ZPD did not affect sleep latency in the morning, while TRZ caused a trend of the reduction.

Comparison of the effects of zolpidem and zopiclone on nocturnal sleep and sleep latency in the morning: a cross-over study in healthy young volunteers

Zolpidem (ZOL) and zopiclone (ZPC) are non-benzodiazepine hypnotics, with unique effects on sleep architecture compared with conventional benzodiazepines. The two compounds have different profiles in action to two major subtypes of the GABA-A receptors, therefore different effects on sleep structure may be expected. In the present study, the effects of ZOL (10mg) and ZPC (7.5mg) were compared in nine healthy young male subjects during nine-night sessions, employing a crossover design. Time courses during the sessions were significantly different between the compounds in the ratio (%) of S2 and S1. Compared to the baseline, an increase of S2 and a decrease of S1 and SR were caused by ZPC, not by ZOL. SWS was increased by both ZPC and ZOL. Significant changes by ZOL were found during the first 150-min, while changes by ZPC were mostly observed during the second 150-min. This might be related to their half-lives. ZOL did not affect sleep latency in the morning, while ZPC caused a significant decrease. Subjective sleepiness, however, was not increased in the ZPC or ZOL mornings. It was speculated that difference in the action to the GABA-A receptor subtypes might be related to the differences in the effects on the sleep architecture between the compounds.

Type of feeding during infancy and later development of schizophrenia

Nutrition may be critical for neurodevelopment and can affect the later development of schizophrenia. Recently, a marked reduction in breast-feeding was reported in infants that developed schizophrenia in later life (McCreadie, R.G., 1997. The Nithsdale Schizophrenia Surveys. 16. Breast-feeding and schizophrenia: preliminary results and hypothesis. Br. J. Psychiatr. 170, 334-337). In the present study, we investigated feeding patterns during the infancy of 100 schizophrenia patients, 37 of their siblings and 200 age-matched healthy controls using a structured written questionnaire. Having been breast-fed was not negatively associated with schizophrenia.

Effects of zolpidem and zopiclone on cognitive and attentional function in young healthy volunteers: an event-related potential study

The effects of zolpidem and zopiclone, non-benzodiazepine ultra-short-acting hypnotics, on cognitive function and vigilance level were investigated in the morning following nocturnal administration using event-related potentials (ERP) and a sleep latency test (SLT). Zopiclone significantly shortened the sleep latency the following morning, whereas zolpidem did not, perhaps due to the difference in the elimination half-lives between the compounds. No significant effect was observed for either drug on the ERP indices, including the P3, mismatch negativity and negative difference components. At a clinically prescribed dosage these sleep inducers have no remarkable effect on cognitive or attentional functions but increase sleepiness of the subjects.

Overnight effects of triazolam on cognitive function: an event-related potentials study

The effects of triazolam on cognitive function and vigilance on the morning following a nocturnal administration were investigated using event-related potentials (ERP) measurement and a sleep latency test (SLT). We previously reported a significant reducing effect on target N1 amplitude on the morning following triazolam administration, suggesting a residual effect of triazolam. In order to demonstrate, which aspect of cognitive function alteration caused the reducing effect on N1 amplitude, we added the ignore condition for ERP measurement, which enabled us to separate mismatch negativity (MMN) from other subcomponents overlapping N1. As a result, MMN was attenuated and sleep latency was shortened on the morning following triazolam administration. Two possibilities were suggested for the mechanism of MMN attenuation. One is GABAergic activation caused by the residual effect of triazolam per se, and the other is the lowered vigilance level demonstrated in the SLT. Further studies are necessary to determine whether this alteration in physiological bases underlying mismatch detection is specific to triazolam and/or other benzodiazepines or related to nonspecific vigilance level.

Decreased plasma cortisol level during alprazolam treatment of panic disorder: a case report

1. Changes in the plasma cortisol level were reported in a male patient with panic disorder during the period of low-dose alprazolam treatment (mean 0.62 +/- 0.15 mg/day) compared with during the period of high-dose period (mean 1.08 +/- 0.28 mg/day). 2. The plasma cortisol level was significantly higher in the low-dose period (mean 13.90 +/- 3.35 micrograms/ml) than in the high-dose period (mean 9.06 +/- 2.75 micrograms/ml) although, paradoxically, the panic attack frequency was significantly lower in the low-dose period (mean 1.35 +/- 0.29/day) than in the high-dose period (mean 2.09 +/- 0.66/day). 3. Thus, the decreased plasma cortisol level during alprazolam treatment of panic disorder was suggested to be caused not by symptom alleviation due to alprazolam but by alprazolam administration itself.

What influences social skills in patients with schizophrenia? Preliminary study using the role play test, WAIS-R and event-related potential

Persons with schizophrenia exhibit disabilities which profoundly affect their social and independent living skills, and social skills training is expected to be an effective treatment for reducing the level of severity of disabilities. Many factors may influence usage and learning of social skills; little is definitively known regarding which disabilities related to schizophrenia compromise social skills. The present report deals with factors affecting social skills. Twenty persons with schizophrenia (DSM-III-R) were tested using a Japanese version of the role play test, the reliability and validity of which were verified. Subjects were also tested using BPRS, auditory event-related potential (ERP) and WAIS-R. Nonverbal skills showed significant positive correlation with the amplitude of the N1 ERP component and age of onset, and 59% of the variance of nonverbal skills was accounted for by these factors using multiple regression analysis. Nonverbal skills are at least partially based on either automatic discriminating processes or selective attention, reflected in N1A. Information receiving and processing skills showed significant positive correlation with Performance IQ and Global Assessment of Functioning, and 61% of the variance of receiving and processing skills was accounted for by BPRS score, PIQ score and age. These skills are not directly related to elementary cognitive function as assessed by analyzing, for example, the ERP P3 component, but are based on more complex neuropsychological function.

[A nation-wide survey on the occurrence of amoebic keratitis in Japan]

Acanthamoeba keratitis in Japan was first reported by Ishibashi in 1988. Since then, the incidence of Acanthamoeba keratitis has gradually increased. We retrospectively analyzed 39 cases, 42 eyes, of amoebic keratitis reported in Japan from 1988 to September 1993. Of the 39 patients, 35 (89.7%) wore contact lenses, 32 (82.1%) soft contact lenses, and 3 (7.7%) hard contact lenses, and 4 (10.3%) did not wear contact lenses. Of the 4 patients without contact lenses, 3 had a history of trauma. Acanthamoeba keratitis is often difficult to diagnose. Twenty-four cases were misdiagnosed as herpetic keratitis. Early diagnosis and adequate therapy are important.