Bradyarrhythmias and Laparoscopy: A Prospective Study of Heart Rate Changes with Laparoscopy

Cardiac arrhythmias are a common complication of laparoscopy. Brady-arrhythmias (including asystole) may be life-threatening. The recent introduction of new shorter-acting muscle relaxants (atracurium and vecuronium), with their lack of vagolytic activity, may exacerbate this situation. At the Royal Women's Hospital there have been several episodes of severe bradyarrhythmias and/or asystole associated with these relaxants. This study evaluated heart rate changes in 49 women during laparoscopy: 47% of patients had arrhythmias, 30% of these being bradyarrhythmias. Nearly all the episodes occurred during carbon dioxide insufflation or with traction on pelvic structures. The life-threatening nature of this phenomenon should be understood by all anaesthetists and gynaecologists engaged in laparoscopic procedures.     

Progressive decrease of left Heschl gyrus and planum temporale gray matter volume in first-episode schizophrenia: a longitudinal magnetic resonance imaging study

BACKGROUND: The Heschl gyrus and planum temporale have crucial roles in auditory perception and language processing. Our previous investigation using magnetic resonance imaging (MRI) indicated smaller gray matter volumes bilaterally in the Heschl gyrus and in left planum temporale in patients with first-episode schizophrenia but not in patients with first-episode affective psychosis. We sought to determine whether there are progressive decreases in anatomically defined MRI gray matter volumes of the Heschl gyrus and planum temporale in patients with first-episode schizophrenia and also in patients with first-episode affective psychosis. METHODS: At a private psychiatric hospital, we conducted a prospective high spatial resolution MRI study that included initial scans of 28 patients at their first hospitalization (13 with schizophrenia and 15 with affective psychosis, 13 of whom had a manic psychosis) and 22 healthy control subjects. Follow-up scans occurred, on average, 1.5 years after the initial scan. RESULTS: Patients with first-episode schizophrenia showed significant decreases in gray matter volume over time in the left Heschl gyrus (6.9%) and left planum temporale (7.2%) compared with patients with first-episode affective psychosis or control subjects. CONCLUSIONS: These findings demonstrate a left-biased progressive volume reduction in the Heschl gyrus and planum temporale gray matter in patients with first-episode schizophrenia in contrast to patients with first-episode affective psychosis and control subjects. Schizophrenia but not affective psychosis seems to be characterized by a postonset progression of neocortical gray matter volume loss in the left superior temporal gyrus and thus may not be developmentally fixed.     

Functional activation of the left amygdala and hippocampus during associative encoding

The human hippocampus is critical to episodic encoding, but the role of the amygdala in memory is less clear. Animal research suggests a role for the amygdala in associative memory, but this has not been examined systematically in humans. Using fMRI, we compared amygdala and hippocampus activation for seven healthy subjects during two visual encoding tasks: serially presented single faces and faces presented as pairs. Single faces activated bilateral hippocampi, but not the amygdala. Paired faces activated bilateral amygdala, but only the left hippocampus. Subtraction of the two conditions revealed greater activation within the left amygdala and hippocampus during paired face encoding, suggesting that associative encoding activates a left-lateralized limbic network including the hippocampus and amygdala.     

高通量筛选JAK-STAT6信号传导通路抑制剂方法的初步建立

目的构建可用于高通量筛选JAK/STAT6信号传导通路抑制剂的工程细胞株,建立稳定可靠的筛选方法。方法利用基因重组和转染技术,将STAT6特异性识别启动子IgE基因序列和虫荧光素酶报告基因联合插入pCMV质粒,脂质体法转染至HeLa细胞,经潮红霉素B抗性筛选及报告基因检测,得到稳定表达虫荧光素酶的工程细胞株。通过优化溶剂DMSO浓度,IL4作用浓度及孵育时间等筛选条件,建立了可靠的筛选方法,并在此基础上对1600种化合物进行了筛选。结果建立的筛选方法稳定可靠,系统Z′因子达到0.64。通过对1600种化合物的筛选,得到3个抑制效果较理想的化合物并测得其IC50值。结论所建立的高通量筛选方法可用于JAK/STAT6信号传导通路抑制剂的筛选。     

Continuous Spinal Anesthesia/Analgesia for Perioperative Management of Morbidly Obese Patients Undergoing Laparotomy for Gastroplastic Surgery

Background: The authors determined prospectively the safety of continuous spinal anesthesia combined with general anesthesia and the efficacy of postoperative pain relief with continuous spinal analgesia for morbidly obese patients undergoing vertical banded gastroplasty. Methods: 27 patients (13 men, 14 women) with a mean body mass index (BMI) of 50.4 ± 7.8 and several co-morbidities were studied. All patients were anesthetized with the same anesthetic regimen, which included midazolam, fentanyl, propofol, muscle relaxants, N₂O, isoflurane and intrathecal bupivacaine. Postoperative pain relief was provided for 5 days and all patients received the same regimen, which included intrathecal bupivacaine, fentanyl and intravenous tenoxicam. The intrathecal analgesic regimen was administered continuously through a pump which had the facility of providing bolus doses when requested in predetermined lockout intervals. Intra-operative monitoring included hemodynamic and respiratory parameters. Additional postoperative monitoring included respiratory rate, degree of sedation, sensory level of anesthesia, motor response and intensity of pain. Results: Intraoperative anesthetic technique was safe and provided satisfactory results in the immediate postoperative period. Furthermore, the postoperative analgesia regimen provided effective analgesia in all patients.The mean doses of fentanyl and bupivacaine infused intrathecally for the first 24 postoperative hours were 14.1 ± 2.0 μg.h^-1 and 0.7 ± 0.1 mg.h^-1 respectively, while the requirements of anal gesia decreased progressively with time. The technique provided effective analgesia with low pain scores, which was reflected by ease in mobilizing and performing physical exercises with the physiotherapist. Only minor complications related to anesthesia and analgesia were encountered. Conclusion: To our knowledge, this technique of anesthesia and postoperative analgesia has not been described before in morbidly obese patients. This regimen merits further controlled trials to establish its place in the perioperative management of morbidly obese patients.     

Cytogenetic and molecular genetic analysis of tumorigenic human bronchial epithelial cells induced by radon alpha particles

To establish a cell culture model for lung carcinogenesis, independent populations of the human papillomavirus 18-immortalized human bronchial epithelial cell line BEP2D were treated with high linear energy transfer radon-simulated alpha-particles, expanded and xenotransplanted into Nu/Nu mice. Six independent cell lines were established from tumors that developed from three separate radiation treatments as follows: treatment (Tx) 1 (30 cGy--two doses), H2BT, Tx 2 (30 cGy-- single dose), R30T1L, R30T2 and R30T3L, Tx 3 (30 cGy--single dose), H1ATN and H1ATBA1. Cytogenetic analysis revealed common changes in all tumor lines: loss of the Y chromosome (ch), one of three copies of ch8, one of three copies of ch14, and one of two copies of ch4p16-pter and ch11p15-pter. Analysis of polymerase chain reaction-amplified short tandem repeats of informative loci confirmed the loss of chY in all lines and loss of heterozygosity (LOH) at eight loci spanning the length of ch8 in all lines from Tx's 1 and 2. Our data support previous studies indicating the presence of tumor suppressor genes on ch8. LOH also was confirmed on ch14 at locus D14S306 in all cell lines from Tx 2 and in one of two lines from Tx 3. This region, 14q12-q13, may contain changes in one of the five known somatostatin receptor genes (SSTR1). No LOH was detected at any of the informative loci tested for on ch4 or ch11.      

Model of normal prepubertal growth

Overheating may cause terminal apnoea and cot death. Rectal temperature and breathing patterns were examined in normal infants at home during the first 6 months of life. Twenty one infants had continuous overnight rectal temperature and breathing recordings for 429 nights (mean 20.4 nights, range 7-30) spaced over the first six months of life. Periods when breathing was 'regular' were directly marked on single night records. Sleep state was determined from respiratory variables. 'Regular' breathing was a reliable marker of 'quiet' sleep (specificity 93%). The duration of 'quiet' sleep increased from 6 to 22 minutes from two weeks to three months of age and then remained static, as did the proportion of sleep spent in the quiet phase (9% to 34%). Rectal temperature fell during 66% of quiet sleep and usually rose during rapid eye movement (REM) sleep. The drop in rectal temperature was maximal at the start of quiet sleep, whereas the maximum rise during REM sleep was reached after 10 to 15 minutes. Oscillations in rectal temperature are associated with changes in sleep and breathing state. The maturation of rectal temperature patterns during the first six months of life are closely related to a maturation of sleep state and breathing patterns.