Visual discrimination and short-term memory for random patterns in patients with a focal cortical lesion

Visual discrimination and short-term recognition memory for computer- generated random patterns were explored in 23 patients with a postsurgical lesion in one of the cortical hemispheres. Their results are compared with those of 23 age-matched volunteers. In a same- different forced-choice discrimination task, d' and log beta (measures of sensitivity and bias), as well as reaction time (RT) were determined. All participants viewed patterns defined either by luminance contrast or isoluminant red-green color contrast, the amplitude of which was adjusted to be 10 times the respective detection threshold level. Block patterns consisting of a 6 x 6 matrix of light and dark (red and green) checks were randomly configured on each presentation. They were presented in pairs, randomly in two visual quadrants for a duration of 200 msec. Three presentation conditions were used: simultaneous presentation of reference and test stimulus, sequential presentation with a short delay (interstimulus interval, ISI = 3 s), and sequential presentation with a long delay (ISI = 6 s). The results indicate that patients with a lesion in the occipitotemporal cortex, the superior temporal cortex and the frontal cortex were significantly impaired on both luminance-contrast and color-contrast pattern discrimination. Patients with damage in the anterior inferotemporal cortex showed no overall impairment. The results suggest that performance in visual discrimination and recognition memory tasks rely on distributed neural processes with more than one neocortical location.      

Laparoscopic gynaecological surgery

Surgical technology has advanced to a level where most gynaecological operations can be performed laparoscopically. Performing laparoscopic surgery requires a degree of surgical skill and structured training is required. A mixture of simulation training and supervised clinical training is required to acquire the skills to perform laparoscopic surgery competently. Attending good quality training courses will enhance the required skills and allow practice of these procedures before attempting these procedures on patients. A patient-centred approach should be adopted when counselling patients pre-operatively, particularly when choosing the route of a procedure. Structured training in technical and non-technical skills is essential.     

Efficiency of low-intensity pulsed ultrasound on distraction osteogenesis in case of delayed callotasis -- clinical results

AIM: Low-intensity pulsed ultrasound has been proven to accelerate fracture healing both clinically and experimentally. In this study the influence of low-intensity pulsed ultrasound during distraction-osteogenesis in case of delayed callotasis was investigated. METHOD: 20 patients could be included in this study. 16 patients initially were treated because of fractures of the lower leg, 2 because of fractures of the femur with resulting shortening of the afflicted limb. One patient suffered from chronic osteitis at the thigh and one from chronic osteitis at the upper arm without previous trauma. Because of delayed callotasis an adjunctive ultrasound treatment device was transcutaneously applied (frequency 1.5 MHz, signal burst width 200 microseconds, signal repetition frequency 1.0 kHz, intensity 30 mW/cm (2)) with the transducer placed at the distraction zone for 20 minutes daily. In all cases in-home treatment was performed. Evaluation was done by radiographic and sonographic controls of the distraction zone during examination of all patients at the outpatients' department every 3-4 weeks. RESULTS: Progress of callotasis was achieved in 15 out of 20 patients. Patients who were smokers during ultrasound therapy showed lower healing rates than those who never smoked. 2 patients suffering from osteitis of the tibia and missing callotasis had to be amputated. 3 other patients needed additional operative treatment including cancellous bone grafts because of missing new bone formation. Negative effects of low-intensity pulsed ultrasound during therapy could not be detected. CONCLUSION: We conclude that ultrasound treatment can accelerate bone maturation and formation in distraction osteogenesis, sometimes even in states of poor callotasis. It may provide a method of great promise in cases where delayed bone formation during distraction osteogenesis occurs.     

Acute Isovolemic Anemia Does Not Impair Peripheral or Central Nerve Conduction

Background: Previous studies have found subtle slowing of responses in tests of addition and digit-symbol substitution during acute severe isovolemic anemia to a hemoglobin concentration of 5 g/dl in healthy unmedicated humans. In this study, the authors tested the hypothesis that such changes relate to the slowing of afferent neural traffic.

Methods: The median nerve was stimulated at the wrist in seven healthy unmedicated volunteers before and after induction of acute isovolemic anemia to a nadir hemoglobin concentration of 5.1 +/- 0.3 g/dl (mean +/- SD). Times for neural impulses to travel from the stimulus site to the brachial plexus, cervical spinal cord, and cerebral cortex were measured using somatosensory evoked potentials. Tests were repeated during acute anemia with the subject breathing oxygen. As a control for time and intrasubject variation, the testing was repeated on a separate day when anemia was not produced at times equivalent to those on the experimental day.

Results: Induced acute severe isovolemic anemia decreased nerve conduction latencies from the wrist to the contralateral cerebral cortex (i.e., to the N20 peak) by 2.3 +/- 1.6% compared with values at a mean hemoglobin concentration of 12.7 g/dl (P < 0.01). These decreased latencies were due solely to an increased peripheral conduction velocity, from the wrist to the brachial plexus (P < 0.05), and were not altered when subjects breathed oxygen (P > 0.05). Conduction velocity from the brachial plexus or cervical spinal cord to the cerebral cortex did not change with acute anemia (P > 0.05). Latencies did not differ on the control day among the times of testing (all P > 0.05), nor did they differ at baseline between the control and experimental days (all P > 0.05).     

Long term clinical outcome of chronic hepatitis C patients with sustained virological response to interferon monotherapy

BACKGROUND: The key end point for treatment efficacy in chronic hepatitis C is absence of detectable virus at six months after treatment. However, the incidence of clinical events during long term follow up of patients with sustained virological response is still poorly documented and may differ between the Eastern and Western world. AIMS: To assess clinical end points during long term follow up of European patients with a sustained virological response to interferon monotherapy. METHODS: Meta-analysis of individual patient data from eight European protocolled follow up studies of interferon treatment for chronic hepatitis C. RESULTS: A total of 286 sustained virological responders and 50 biochemical responders (detectable virus but normal alanine aminotransferase levels) were followed up for 59 months. Fifteen sustained virological responders (5.2%) had cirrhosis before treatment and 112 (39%) had genotype 1. The late virological relapse rate after five years of follow up was 4.7% (95% confidence interval (CI) 2.0-7.4) among sustained virological responders; all late relapses occurred within four years after treatment. Among sustained virological responders, the rate of decompensation after five years of follow up was 1.0% (95% CI 0.0-2.3) and none developed hepatocellular carcinoma (HCC). Survival was comparable with the general population, matched for age and sex, the standard mortality ratio being 1.4 (95% CI 0.3-2.5). Clinical outcome of patients with cirrhosis was similar to other sustained virological responders. For biochemical responders, the rates of development of decompensation and HCC during long term follow up were 9.1% (95% CI 0.5-17.7) and 7.1% (95% CI 0-15.0), respectively. CONCLUSIONS: Five year survival of European sustained virological responders was similar to the overall population, matched for age and sex. No HCCs were detected during long term follow up.     

Induction of T helper cell type 1 response and elimination of HBeAg during treatment with IL-12 in a patient with therapy-refractory chronic hepatitis B

This study reports the increase of immunoregulatory T helper cell type 1 response and elimination of HBV-DNA during IL-12 therapy in a patient with chronic hepatitis B virus infection who had not responded to three previous interferon-alpha therapies and one treatment with Famciclovir over a period of 6 years. The patient received IL-12 at a dose of 0.5 microgram/kg bodyweight weekly. Peripheral blood mononuclear cells were isolated before and during IL-12 application and incubated for 7 days with specific type 1 (purified protein derivative) and type 2 (tetanus-toxoid) TH cell antigens as well as with a macrophage/monocyte activating antigen (Bacille Calmette-Guérin). In the supernatants cytokines were determined by a double-sandwich ELISA. After 8 weeks HBV-DNA became negative and HBeAg seroconversion to anti-HBeAg occurred. Immunologically the loss of viremia was accompanied by a strong increase of the purified protein derivative-induced production of the type 1 cytokine interferon-gamma (1219 pg/mL before, 13,138 pg/mL after IL-12 therapy). Furthermore, Bacille Calmette-Guérin-induced secretion of the macrophage/monocyte-associated cytokines IL-1, tumor necrosis factor-alpha and granulocyte-macrophage colony-stimulating factor was higher at the end of therapy. This case indicates that IL-12 enhances type 1 T helper cell activity which may be a predisposition for elimination of HBeAg and successful treatment of hepatitis B.     

Increasing applicability of liver transplantation for patients with hepatitis B-related liver disease

Liver transplantation in patients with hepatitis B has been under discussion for 20 years because of inferior results without reinfection prophylaxis; therefore, we analyzed our overall experience with liver transplantation in hepatitis B patients with immunoprophylaxis, particularly the influence of the available antiviral treatment in different periods. From 1988 to 2000, 228 liver transplants in 206 hepatitis B patients were performed. Indications were acute liver failure (10%), hepatitis B virus (HBV) cirrhosis alone (67%) or with hepatitis D virus (HDV) (13%), or hepatitis C virus (HCV) coinfection (7%). All patients received long-term immunoprophylaxis (anti-HBs > 100 U/L). HBV DNA-positive patients were treated before and after surgery with famciclovir or lamivudine since 1993 and 1996, respectively. Since 1993, antivirals also were used for HBV reinfection. The 1-, 5-, and 10-year patient survival rates were 91%, 81%, and 73%. In patients with hepatocellular carcinoma (HCC) (60% 5-year survival, P <.01) or HBV reinfection (69% 5-year survival, P <.01) survival was significantly impaired. Those with HDV or HCV coinfection had a slightly better survival than with HBV monoinfection (P >.05, not significant). Preoperative positive HBV DNA (hybridization-assay) test results were associated with a slightly impaired patient survival (78% 5-year survival, P >.05, not significant versus DNA-negative). Preoperative positive hepatitis B e antigen (HBeAg) predicted significantly worse survival (P <.05 versus negative HBeAg). Graft loss caused by reinfection was most frequent before the availability of antiviral drugs. Two-year patient survival increased from 85% in era I (1988-1993) to 94% in era III (1997-2000, P <.05). The 2-year recurrence rates in these 2 periods were 42% and 8% (P <.05). In conclusion, excellent long-term results can be achieved in hepatitis B patients after liver transplantation with modern strategies, and survival rates are similar to other indications. Based on our experience, hepatitis B patients, including those with active viral replication, should not be excluded from liver transplantation.     

雪灵芝对二乙基亚硝胺诱导大鼠肝癌组织细胞的抑制作用

目的：验证雪灵芝是否具有抑制大鼠肝癌的功效。方法：实验于2003—09/2004—08在广西疾病预防控制中心SPF级动物实验室完成。选用健康成年SD大鼠160只。按体质量分层随机分为5组：空白对照组、模型组、雪灵芝高剂量组、雪灵芝中剂量组和雪灵芝低剂量组，每组32只。雪灵芝高、中、低剂量组大鼠分别灌胃2．500，1．250，0．625mL/kg雪灵芝溶液，阴性对照组和模型组灌胃等量蒸馏水，1次／d，连续60d。第61天开始雪灵芝高、中、低剂量组和模型组灌胃二乙基亚硝胺溶液，对照组灌胃等量的生理盐水。于停止灌胃90d后各组处死一半受试大鼠（雌雄各半），检测血常规及血清主要生化指标，观察各脏器大体形态改变、脏器的癌变程度。1周后给剩余大鼠灌胃雪灵芝溶液（不含二乙基亚硝胺）。7周后处死余下的一半雄性大鼠，进行相同操作。8周后处死余下的全部大鼠，操作及检测方法同前。结果：纳入的160只SD大鼠，145只进入结果分析，15只脱落。①病理切片检查结果：除阴性对照组，其他各组大鼠肝组织均发生癌变或癌前病变。雪灵芝高、中、低剂量组的癌前病变发生率与模型组相近（P〉0．05）；癌变的发生率均低于模型组，差异有显著性意义（P〈0．05，0．01）。②大体标本检查结果：阴性对照组大鼠肝脏的大体标本均无异常改变，其他各组大鼠的肝脏有些可见表面粗糙等病理改变。模型组大体标本病理改变的阳性率高于雪灵芝高、中、低剂量组，差异有显著性意义（P〈0．05）。肉眼观模型组癌变发生率高于其他各组。③其他脏器检查结果：模型组2只大鼠有肝癌肺转移。结论：以较大剂量的二乙基亚硝胺连续灌胃30d可以复制大鼠肝癌模型；雪灵芝对二乙基亚硝胺诱导的大鼠肝癌具有预防和抑制的作用。     

44-j?hrige Patientin mit unklarer Leberwerterh?hung und famili?r geh?uftem Gallensteinleiden

"Low phospholipid associated cholelithiasis" (LPAC) syndrome is an important differential diagnosis in younger patients with biliary symptoms after cholecystectomy and concomitant elevated serum liver tests. Typical symptoms include recurrence of biliary colics after cholecystectomy, echogenic material in the intrahepatic bile ducts, intrahepatic cholestasis of pregnancy or cholestasis under hormonal contraception and a family history of gallstone disease. Patients with LPAC syndrome can be successfully treated with ursodeoxycholic acid.