Limited liver resections in the posterosuperior segments: international multicentre propensity score-matched and coarsened exact-matched analysis comparing the laparoscopic and robotic approaches

Background

Limited liver resections (LLRs) for tumours located in the posterosuperior segments of the liver are technically demanding procedures. This study compared outcomes of robotic (R) and laparoscopic (L) LLR for tumours located in the posterosuperior liver segments (IV, VII, and VIII).

Methods

This was an international multicentre retrospective analysis of patients who underwent R-LLR or L-LLR at 24 centres between 2010 and 2019. Patient demographics, perioperative parameters, and postoperative outcomes were analysed; 1 : 3 propensity score matching (PSM) and 1 : 1 coarsened exact matching (CEM) were performed.

Results

Of 1566 patients undergoing R-LLR and L-LLR, 983 met the study inclusion criteria. Before matching, 159 R-LLRs and 824 L-LLRs were included. After 1 : 3 PSM of 127 R-LLRs and 381 L-LLRs, comparison of perioperative outcomes showed that median blood loss (100 (i.q.r. 40–200) versus 200 (100–500) ml; P = 0.003), blood loss of at least 500 ml (9 (7.4 per cent) versus 94 (27.6 per cent); P < 0.001), intraoperative blood transfusion rate (4 (3.1 per cent) versus 38 (10.0 per cent); P = 0.025), rate of conversion to open surgery (1 (0.8 per cent) versus 30 (7.9 per cent); P = 0.022), median duration of Pringle manoeuvre when applied (30 (20–46) versus 40 (25–58) min; P = 0.012), and median duration of operation (175 (130–255) versus 224 (155–300); P < 0.001) were lower in the R-LLR group compared with the L-LLR group. After 1 : 1 CEM of 104 R-LLRs with 104 L-LLRs, R-LLR was similarly associated with significantly reduced blood loss and a lower rate of conversion to open surgery.

Conclusion

Based on a matched analysis of well selected patients, both robotic and laparoscopic access could be undertaken safely with good outcomes for tumours in the posterosuperior liver segments.

Determination of Aflatoxins in Agricultural Products: Use of Aqueous Acetone for Extraction

An analytical procedure originally developed for the determination of aflatoxins in cottonseed products has been modified for application to many agricultural materials. Aflatoxins are rapidly extracted free of lipid contamination with 70% acetone. Many interfering pigments are removed from the crude extract by precipitation as insoluble lead derivatives, transfer of aflatoxins into chloroform, and further purification of the chloroform extract with silica gel.

The procedure was compared with four recently proposed methods for the analysis of peanut products. This technique is capable of detecting as little as 0.3 ppb of aflatoxin Bi in peanuts and peanut butters. Adequate recovery of added aflatoxins was obtained when this method was applied to numerous different agricultural products.

Effects of proton pump inhibitor on the human gut microbiome profile in multi-ethnic groups in Singapore

INTRODUCTION

The objectives of this study were to examine the effects of ethnicity, gender and a proton pump inhibitor (PPI), omeprazole, on the human gut microbiome. PPIs are commonly used for the treatment of acid-related disorders. We hypothesised that PPI therapy might perturb microbial communities and alter the gut microbiome.

METHODS

Healthy subjects of Chinese (n = 12), Malay (n = 12) and Indian (n = 10) ancestry, aged 21-37 years, were enrolled. They provided a baseline stool sample (Day 1) and were then given a course of omeprazole at therapeutic dose (20 mg daily) for seven days. Stool samples were collected again on Day 7 and 14 (one week after stopping omeprazole). Microbial DNA was extracted from the stool samples, followed by polymerase chain reaction, library construction, 16S rRNA sequencing using Illumina MiSeq, and statistical and bioinformatics analyses.

RESULTS

The findings showed an increase in species richness (p = 0.018) after omeprazole consumption on Day 7, which reverted to baseline on Day 14. There were significant increases in the relative abundance of Streptococcus vestibularis (p = 0.0001) and Veillonella dispar (p = 0.0001) on Day 7, which diminished on Day 14. Faecalibacterium prausnitzii, Sutterella stercoricanis and Bacteroides denticanum were characteristic of Chinese, Malays and Indians, respectively. Lactobacillaceae and Bacteroides xylanisolvens were the signature taxa of male and female subjects, respectively.

CONCLUSION

The study demonstrated alterations in the gut microbiome following omeprazole treatment. This may explain the underlying pathology of increased risk of Clostridium difficile infections associated with omeprazole therapy.

The Cambridge Prognostic Groups for improved prediction of disease mortality at diagnosis in primary non-metastatic prostate cancer: a validation study

BACKGROUND

The purpose of this study is to validate a new five-tiered prognostic classification system to better discriminate cancer-specific mortality in men diagnosed with primary non-metastatic prostate cancer.

METHODS

We applied a recently described five-strata model, the Cambridge Prognostic Groups (CPGs 1-5), in two international cohorts and tested prognostic performance against the current standard three-strata classification of low-, intermediate- or high-risk disease. Diagnostic clinico-pathological data for men obtained from the Prostate Cancer data Base Sweden (PCBaSe) and the Singapore Health Study were used. The main outcome measure was prostate cancer mortality (PCM) stratified by age group and treatment modality.

RESULTS

The PCBaSe cohort included 72,337 men, of whom 7162 died of prostate cancer. The CPG model successfully classified men with different risks of PCM with competing risk regression confirming significant intergroup distinction (p < 0.0001). The CPGs were significantly better at stratified prediction of PCM compared to the current three-tiered system (concordance index (C-index) 0.81 vs. 0.77, p < 0.0001). This superiority was maintained for every age group division (p < 0.0001). Also in the ethnically different Singapore cohort of 2550 men with 142 prostate cancer deaths, the CPG model outperformed the three strata categories (C-index 0.79 vs. 0.76, p < 0.0001). The model also retained superior prognostic discrimination in the treatment sub-groups: radical prostatectomy (n = 20,586), C-index 0.77 vs. 074; radiotherapy (n = 11,872), C-index 0.73 vs. 0.69; and conservative management (n = 14,950), C-index 0.74 vs. 0.73. The CPG groups that sub-divided the old intermediate-risk (CPG2 vs. CPG3) and high-risk categories (CPG4 vs. CPG5) significantly discriminated PCM outcomes after radical therapy or conservative management (p < 0.0001).

CONCLUSIONS

This validation study of nearly 75,000 men confirms that the CPG five-tiered prognostic model has superior discrimination compared to the three-tiered model in predicting prostate cancer death across different age and treatment groups. Crucially, it identifies distinct sub-groups of men within the old intermediate-risk and high-risk criteria who have very different prognostic outcomes. We therefore propose adoption of the CPG model as a simple-to-use but more accurate prognostic stratification tool to help guide management for men with newly diagnosed prostate cancer.

Comparison of Kaposi Sarcoma Risk in Human Immunodeficiency Virus-Positive Adults Across 5 Continents: A Multiregional Multicohort Study

BACKGROUND

We compared Kaposi sarcoma (KS) risk in adults who started antiretroviral therapy (ART) across the Asia-Pacific, South Africa, Europe, Latin, and North America.

METHODS

We included cohort data of human immunodeficiency virus (HIV)-positive adults who started ART after 1995 within the framework of 2 large collaborations of observational HIV cohorts. We present incidence rates and adjusted hazard ratios (aHRs).

RESULTS

We included 208140 patients from 57 countries. Over a period of 1066572 person-years, 2046 KS cases were diagnosed. KS incidence rates per 100000 person-years were 52 in the Asia-Pacific and ranged between 180 and 280 in the other regions. KS risk was 5 times higher in South African women (aHR, 4.56; 95% confidence intervals [CI], 2.73-7.62) than in their European counterparts, and 2 times higher in South African men (2.21; 1.34-3.63). In Europe, Latin, and North America KS risk was 6 times higher in men who have sex with men (aHR, 5.95; 95% CI, 5.09-6.96) than in women. Comparing patients with current CD4 cell counts ≥700 cells/µL with those whose counts were <50 cells/µL, the KS risk was halved in South Africa (aHR, 0.53; 95% CI, .17-1.63) but reduced by ≥95% in other regions.

CONCLUSIONS

Despite important ART-related declines in KS incidence, men and women in South Africa and men who have sex with men remain at increased KS risk, likely due to high human herpesvirus 8 coinfection rates. Early ART initiation and maintenance of high CD4 cell counts are essential to further reducing KS incidence worldwide, but additional measures might be needed, especially in Southern Africa.

Transgenerational effects of paternal heroin addiction on anxiety and aggression behavior in male offspring

BACKGROUND

Heroin addiction is a growing concern, affecting the socioeconomic development of many countries. Little is known about transgenerational effects on phenotype changes due to heroin addiction. This study aims to investigate changes in level of anxiety and aggression up to four different generations of adult male rats due to paternal exposure to heroin.

METHODS

Male Sprague-Dawley rats were exposed with heroin intraperitoneally (i.p.) twice-daily for 14 days with increasing dosage regimen (F0-heroin). Male Sprague-Dawley rats (6-weeks-old) were divided into: (1) heroin exposed group (F0-heroin) and (2) control group treated with saline solution (F0-control). The dosage regime started with the lowest dose of 3 mg/kg per day of heroin followed by 1.5 mg/kg increments per day to a final dose of 13.5 mg/kg per day. Offspring were weaned on postnatal day 21. The adult male offspring from each generation were then mated with female-naïve rats after 2 weeks of heroin absence. Open field test and elevated plus maze test were used to study the anxiety level, whereas resident intruder test was used to evaluate aggression level in the addicted male rats and their offspring.

RESULTS

Heroin exposure in male rats had resulted in smaller sizes of the litters compared to the control. We observed a higher anxiety level in the F1 and F2 progenies sired by the heroin exposed rats (F0) as compared to the control rats. Paternal heroin exposure also caused significantly more aggressive offspring in F1 compared to the control. The same pattern was also observed in the F2.

CONCLUSION

Our results demonstrated that the progenies of F1 and F2 sustained higher levels of anxiety and aggression which are due to paternal heroin exposure.

Systematic characterization and comparison of the CYP2C9 variability of the Orang Asli in Malaysia with 12 populations

We conducted a systematic characterization of CYP2C9 variants in 61 Orang Asli and 96 Singaporean Malays using the whole genome sequences data and compared the variants with the other 11 HapMap populations. The frequency of rs1057910 (CYP2C9*3) is the highest in the Orang Asli compared to other populations. Three alleles with clinical implication were detected in the Orang Asli while 2 were found in the Singaporean Malays. Large numbers of the Orang Asli are predicted to have reduced metabolic capacity and therefore they would require a lower dose of drugs which are metabolized by CYP2C9. They are also at increased risks of adverse effects and therapeutic failures. A large number of CYP2C9 variants in the Orang Asli were not in the Hardy Weinberg Equilibrium which could be due to small sample size or mutations that disrupt the equilibrium of allele frequencies. In conclusion, different polymorphism patterns, allele frequencies, genotype frequencies and LD blocks are observed between the Orang Asli, the Singaporean Malays and the other populations. The study provided new information on the genetic polymorphism of CYP2C9 which is important for the implementation of precision medicine for the Orang Asli.

Serous cystic neoplasm of the pancreas: a multinational study of 2622 patients under the auspices of the International Association of Pancreatology and European Pancreatic Club (European Study Group on Cystic Tumors of the Pancreas)

OBJECTIVES

Serous cystic neoplasm (SCN) is a cystic neoplasm of the pancreas whose natural history is poorly known. The purpose of the study was to attempt to describe the natural history of SCN, including the specific mortality.

DESIGN

Retrospective multinational study including SCN diagnosed between 1990 and 2014.

RESULTS

2622 patients were included. Seventy-four per cent were women, and median age at diagnosis was 58 years (16-99). Patients presented with non-specific abdominal pain (27%), pancreaticobiliary symptoms (9%), diabetes mellitus (5%), other symptoms (4%) and/or were asymptomatic (61%). Fifty-two per cent of patients were operated on during the first year after diagnosis (median size: 40 mm (2-200)), 9% had resection beyond 1 year of follow-up (3 years (1-20), size at diagnosis: 25 mm (4-140)) and 39% had no surgery (3.6 years (1-23), 25.5 mm (1-200)). Surgical indications were (not exclusive) uncertain diagnosis (60%), symptoms (23%), size increase (12%), large size (6%) and adjacent organ compression (5%). In patients followed beyond 1 year (n=1271), size increased in 37% (growth rate: 4 mm/year), was stable in 57% and decreased in 6%. Three serous cystadenocarcinomas were recorded. Postoperative mortality was 0.6% (n=10), and SCN's related mortality was 0.1% (n=1).

CONCLUSIONS

After a 3-year follow-up, clinical relevant symptoms occurred in a very small proportion of patients and size slowly increased in less than half. Surgical treatment should be proposed only for diagnosis remaining uncertain after complete workup, significant and related symptoms or exceptionally when exists concern with malignancy. This study supports an initial conservative management in the majority of patients with SCN.

TRIAL REGISTRATION NUMBER

IRB 00006477.

Systematic pharmacogenomics analysis of a Malay whole genome: proof of concept for personalized medicine

BACKGROUND

With a higher throughput and lower cost in sequencing, second generation sequencing technology has immense potential for translation into clinical practice and in the realization of pharmacogenomics based patient care. The systematic analysis of whole genome sequences to assess patient to patient variability in pharmacokinetics and pharmacodynamics responses towards drugs would be the next step in future medicine in line with the vision of personalizing medicine.

METHODS

Genomic DNA obtained from a 55 years old, self-declared healthy, anonymous male of Malay descent was sequenced. The subject's mother died of lung cancer and the father had a history of schizophrenia and deceased at the age of 65 years old. A systematic, intuitive computational workflow/pipeline integrating custom algorithm in tandem with large datasets of variant annotations and gene functions for genetic variations with pharmacogenomics impact was developed. A comprehensive pathway map of drug transport, metabolism and action was used as a template to map non-synonymous variations with potential functional consequences.

PRINCIPAL FINDINGS

Over 3 million known variations and 100,898 novel variations in the Malay genome were identified. Further in-depth pharmacogenetics analysis revealed a total of 607 unique variants in 563 proteins, with the eventual identification of 4 drug transport genes, 2 drug metabolizing enzyme genes and 33 target genes harboring deleterious SNVs involved in pharmacological pathways, which could have a potential role in clinical settings.

CONCLUSIONS

The current study successfully unravels the potential of personal genome sequencing in understanding the functionally relevant variations with potential influence on drug transport, metabolism and differential therapeutic outcomes. These will be essential for realizing personalized medicine through the use of comprehensive computational pipeline for systematic data mining and analysis.

Nontraumatic hemorrhagic stroke in young adults in taiwan

We reviewed the medical records and imaging studies on the in-hospital patients to investigate the clinical and etiological patterns in hemorrhagic stroke in young patients. We evaluated 210 patients (131 males and 79 females) aged 15-45 years who had traumatic hemorrhagic stroke between April 1, 1986, and November 30, 1992. Nontraumatic intracerebral hemorrhage was diagnosed in 170 patients (80.9%). The main causes of nontraumatic intracerebral hemorrhage were hypertension, ruptured arteriovenous malformation, and blood dyscrasia. A cause was not found in 42 patients (24.7%). Subarachnoid hemorrhage was found in 40 patients (19.1%). The main causes were ruptured aneurysms and arteriovenous malformations. The overall in-hospital survival of young patients with hemorrhagic stroke was 64.7%. Young adults with nontraumatic intracerebral and subarachnoid hemorrhage are a heterogeneous group. Hypertension accounts for about one-third of intracerebral hemorrhage and is an important preventable cause of hemorrhagic stroke in young adults in Taiwan.

Gastrocolic fistula: a rare complication of gastric carcinoma

Malignant gastrocolic fistula formation is a rare complication of gastric carcinoma. We report a cachectic 82-year-old woman who presented with upper abdominal pain, diarrhoea, loss of weight and loss of appetite. Further investigation of her symptoms revealed a gastrocolic fistula connecting the ulcerated tumour of the body of the stomach to the splenic flexure of the colon.

Molecular and pharmacodynamic properties of estrogenic extracts from the traditional Chinese medicinal herb, Epimedium

The Chinese medicinal herb, Epimedium, used traditionally for bone health exerts estrogenic activity (EA) in vitro. A genetically characterized Epimedium brevicornum (EB) extract induced biphasic responses in the mRNA and protein expression of the estrogen-regulated progesterone receptor gene in breast cancer (MCF-7) cells. These changes were mirrored changes in estrogenic receptor (ERalpha) content. In male Sprague-Dawley rats, administration of the estrogenic prodrug, estradiol valerate increased area-under-curve of serum effects for ERalpha (AUC difference: 18,900EA(ERalpha) min; 95% CI: 0-37,800; p = 0.05) and breast cancer cell (MCF-7) growth (AUC difference: 30,200EA(MCF-7) min; 95% CI: 24,200-36,200; p<0.001), compared to placebo. Oral administration of Epimedium brevicornum increased ERalpha activity (1320EA(ERalpha) min, p<0.01). Our data indicate that estrogen-responsive bioassays can measure the pharmacokinetic/pharmacodynamics of estrogenic activity in serum. Epimedium brevicornum extract increases estrogenic activity in serum and human studies are required to evaluate whether Epimedium extracts have utility for estrogen replacement therapy.

Induction of stanniocalcin-1 expression in apoptotic human nasopharyngeal cancer cells by p53

There is growing evidence to suggest that altered patterns of STC1 gene expression relate to the process of human cancer development. Our previous study has demonstrated the involvement of HIF-1 in the regulation of STC1 expression in human cancer cells. Recently, STC1 has been implicated as a putative pro-apoptotic factor in regulating the cell-death mechanism. Thus it would be of interest to know if STC1 is regulated by a tumor suppressor protein, p53. In this study, we provide evidence to demonstrate that the induction of STC1 expression in apoptotic human nasopharyngeal cancer cells (CNE2) is mediated by the activation of p53. Our study indicated that the activation of STC1 and heat-shock protein (hsp70) accompanied iodoacetamide (IDAM)-induced apoptosis in CNE-2. In addition, cellular events such as GSH depletion, mitochondrial membrane depolarization, reduction of pAkt and procaspase-3, and the induction of total p53 protein, acetylated p53, and annexin V positive cells were observed. The activation of STC1 was found to be at the transcriptional level and was independent of prior protein synthesis. Co-treatment of IDAM exposed cells with N-acetyl cysteine (NAC) prevented cell death by restoring mitochondrial membrane potential and cellular levels of GSH. NAC co-treatment also suppressed STC1 expression but had no effect on IDAM-induced hsp70 expression. RNA interference studies demonstrated that endogenous p53 was involved in activating STC1 gene expression. Collectively, the present findings provide the first evidence of p53 regulation of STC1 expression in human cancer cells.

Pulmonary complications following adult liver transplantation

PURPOSE

Pulmonary complications frequently occur after liver transplantation, but the risk factors associated with them have not been fully determined. We therefore sought to identify risk factors for pulmonary complications among adult liver transplant recipients.

METHODS

We retrospectively reviewed the medical records of 128 consecutive adult patients who underwent 131 liver transplantations during 2001. We evaluated the incidence, time of onset, and outcome of radiographically determined pulmonary complications, as well as the factors predictive of infectious complications.

RESULTS

Postoperative chest roentgenograms detected 68 cases of pulmonary complications, including pleural effusion (n = 50), atelectasis (n = 6), pneumonia (n = 6), pulmonary edema (n = 5), and acute respiratory distress syndrome associated with pneumonia (n = 1). Of the seven patients with pneumonia, five died. On univariate analysis the risk factors predictive for pneumonia were high serum creatinine and total bilirubin, hemodialysis at the time of occurrence, and history of acute rejection and on multivariate analysis increased total bilirubin and history of acute rejection. Pulmonary complications were dependent on the medical condition at the time of occurrence rather than on the preoperative condition.

CONCLUSIONS

Although the incidence of pneumonia in liver recipients was relatively low, the mortality rate in patients who developed this complication was high. High-risk patients undergoing liver transplantation thus require early diagnosis and intensive treatment to diminish the morbidity and mortality associated with pulmonary complications.

Severe acute gastric dilatation causing respiratory failure

Severe acute gastric dilatation occurring in the absence of bowel obstruction is uncommon. We report acute gastric dilatation developing postoperatively in a 79-year-old man, culminating in respiratory failure. On the third postoperative day following bilateral inguinal hernia repair, he developed abdominal distension with absent bowel sounds. Abdominal radiograph showed a grossly distended gastric shadow and small bowel dilatation. The patient's oxygen saturation then deteriorated suddenly and severely, necessitating intubation. He recovered well with conservative measures.

Dynamics of progestogenic activity in serum following administration of Ligusticum chuanxiong

Many women are using botanical alternatives for menopausal hormone replacement therapy (HRT) because current progestins, compounds with progesterone activity, have adverse risk profiles. However the development of phyto-progestins for HRT is hampered by the absence of basic pharmacokinetic/pharmacodynamic (PK/PD) data due to the lack of methods to capture summated effects of the numerous compounds that contribute to bioactivity in vivo. In this study, we explored the utility of progesterone receptor (PR)-driven bioassays to track changes in serum progestogenic activity following administration of traditional Chinese medicinal herb, Ligusticum chuanxiong, with potent progestogenic activity. Sensitive and specific (>300-fold) increases in progestogenic activity were observed when HeLa cells transfected with PR and a PR-driven promoter were exposed to the progestogenic drug, medroxy-progesterone acetate (MPA), suggesting the utility of the bioassay to measure progestogenic effects for PK/PD studies. Progestogens were administered to male Sprague-Dawley rats and serum extracted for measurement of progestogenic activity. Effect-time studies indicate that injection of MPA and L. chuanxiong extract raised area-under-curve of progestogenic activity in sera by 8.2-fold (p<0.001) and 4.5-fold (p<0.01) respectively, compared to sera from rats administered vehicle only. Administration of MPA and L. chuanxiong extract by the oral route resulted in a 5.4 (p<0.001) and 2.3-fold (p=0.07) increase respectively. Our data suggest that PR-responsive reporter gene bioassays can measure bioavailability of compounds, known and unknown, of complex botanicals for hormone replacement therapy. L. chuanxiong extracts exert progestogenic activity in vivo, and may have utility for progesterone-replacement therapy.

Prospective study of the effectiveness of percutaneous transhepatic photodynamic therapy for advanced bile duct cancer and the role of intraductal ultrasonography in response assessment

BACKGROUND AND STUDY AIMS

We evaluated the therapeutic effects of percutaneous transhepatic photodynamic therapy (PDT) in patients with advanced bile duct cancer. The utility of intraductal ultrasonography (IDUS) for the assessment of responses and for regular follow up after PDT was also examined.

METHODS

Percutaneous transhepatic biliary drainage (PTBD) was initiated before PDT. Following dilation and maturation of the PTBD tract, percutaneous PDT was performed. Intraluminal photoactivation was carried out using percutaneous cholangioscopy 2 days after intravenous application of a hematoporphyrin derivative. All patients were additionally provided with percutaneous bile duct drainage catheters after PDT. IDUS was conducted monthly to measure the thickness of the tumor mass before and after PDT.

RESULTS

24 patients with advanced cholangiocarcinomas (Bismuth IIIa, n = 4; IIIb, n = 10; IV, n = 10) were treated with PDT. At 3 months after PDT, the mean thickness of the tumor mass had decreased from 8.7 +/- 3.7 mm to 5.8 +/- 2.0 mm (P < 0.01). At 4 months after PDT, the thickness of the mass had increased to 7.0 +/- 3.7 mm. Quality of life indices improved dramatically and remained stable 1 month after PDT; the Karnofsky index increased from 39.1 +/- 11.36 to 58.2 +/- 22.72 points (P = 0.003). The 30-day mortality rate was 0 %, and the median survival time was 558 +/- 178.8 days (current range 62 - 810 days).

CONCLUSIONS

PDT using percutaneous cholangioscopy is safe and effective for advanced hilar cholangiocarcinoma, and seems to prolong survival. IDUS is useful for evaluating changes in the thickness of the tumor mass after PDT.

Endoluminal gastroplication for treatment of patients with classic gastroesophageal reflux symptoms and borderline 24-h pH studies

BACKGROUND

Patients with classic gastroesophageal reflux disease (GERD) symptoms and borderline 24-h pH studies are not considered to be good candidates for surgical fundoplication. Endoluminal gastroplication (ELGP) is a new endoscopic treatment for patients with GERD. The aim of this study was to evaluate the efficacy of ELGP in these patients.

METHODS

Patients with heartburn, regurgitation symptoms and a DeMeester score of less than 30 were studied. ELGP involved placement of two or three plications within 2 cm of the gastroesophageal junction. Clinical outcomes measured were heartburn symptom score (HSS), regurgitation frequency score (RFS) and medication use.

RESULTS

Twenty-five patients (11 M, 14 F, mean age of 51 years) had a medication use of 11.5 doses of proton-pump inhibitors per week prior to ELGP. Average lower esophageal sphincter pressure measured 15 +/- 8 mmHg, and average DeMeester score was 18 +/- 8. Nine patients had hiatal hernias and 11 had esophagitis. Twenty-four patients were available for a mean follow-up of 12 months. HSS significantly decreased from 48 to 17 (P < 0.01) and RFS was reduced from 1.8 to 0.7 (P < 0.01). Proton-pump inhibitor use was 5.3 doses per week (P < 0.01) post-ELGP; 12 patients (50%) were off medications, 3 (13%) had a 50% reduction in medication use, and in 9 (37%) there was no change. Complications were bleeding in one patient and aspiration pneumonia in another patient.

CONCLUSIONS

Endoluminal gastroplication provides symptomatic relief for patients with classic GERD symptoms despite medical therapy and borderline 24-h pH studies.

Sorption and degradation of steroid hormones in soils during transport: column studies and model evaluation

Natural and synthetic analogues of steroid hormones and their metabolites have emerged as contaminants of concern. Characterizing sorption and degradation processes is essential to assess the environmental distribution, persistence, and ecological significance of steroid hormones in terrestrial and aquatic systems. We examined the fate and transport of testosterone and 17beta-estradiol by conducting a series of fast-flow-velocity transport experiments under pulse-type and flow-interruption boundary conditions in columns packed with a surface soil, freshwater sediment, and two sands. Flow-interruption experiments provided independent estimates of degradation coefficients for the parent hormones and their metabolites, while pulse-input type experiments were used to identify transport mechanisms for hormones by employing forward modeling approaches. Estimated degradation rate coefficients (k) for the hormones from flow-interruption experiments ranged from 0.003 to 0.015 h(-1) for testosterone and from 0.0003 to 0.075 h(-1) for estradiol, similar to those observed in batch studies. Degradation rate coefficients for the two primary metabolites were 1-2 orders of magnitude larger than those for the parent chemicals. Estimated k values decreased with column life as a result of nutrient depletion. Large sorption by soils of the parent and metabolites (log Koc approximately 2.77-3.69) did not appear to hinder degradation; k values were an order of magnitude smaller than the estimated sorption mass-transfer constants. Differences in hormone breakthrough curves from a single-pulse displacement and those predicted using independently estimated parameters suggest that modeling hormone degradation as a simple first-order kinetic process may be sufficient, but not accurate.

Differential inducibilities of GFAP expression, cytostasis and apoptosis in primary cultures of human astrocytic tumours

Glial fibrillary acidic protein (GFAP) is an astrocytic lineage-specific intermediate filament protein, and its expression or non-expression is inversely correlated with the tumourigenecity of astrocytoma cells. To estimate the GFAP levels of astrocytes in intracranial tumour tissues, we established primary cultures from six astrocytic tumour specimens and used a double-staining flow cytometric method to detect the different levels of GFAP among these primary cultures. Although these primary cultures exhibited the same Matrigel invasiveness, their GFAP expression is inversely related to the rate of cell growth and the histologic grade of the original tumour. Phenylacetate, 12-O-tetradecanoylphorbol-13-acetate (TPA) and sodium butyrate, which are potent inducers of differentiation in various cancer cells, have been examined for their effects on these primary cultures. Cytostasis was more or less caused by these compounds in all six primary cultures, but induction of GFAP was observed only in the primary culture derived from a less malignant astrocytoma specimen having the highest intrinsic GFAP level. Interestingly, this primary culture, but not others, also exhibited increased HRG-alpha expression after phenylacetate or sodium butyrate treatment. Loss of the inducibility of differentiation-related gene expression could be one of the events involved in the malignant progression of astrocytomas. In addition, the chemotherapeutic agent BiCNU has a killing effect on all six primary culture cells, with LD50 less than 60 nM. The underlying mechanism was through the induction of apoptosis in these primary culture cells regardless of their varying malignancies of original tumours. However, unlike colon cancer and leukaemia cells, sodium butyrate could not induce apoptosis within 4 days in these astrocytic tumour cells, indicating that the cell context of different cell types indeed determined the ability of sodium butyrate to induce apoptosis.

A survey on anesthesia for thoracoscopic sympathetic surgery in treatment of hyperhidrosis palmaris in Taiwan

Thoracoscopic approach to sympathetic surgery has gained its popularity and emerged as the main stream in the treatment of hyperhidrosis palmaris in Taiwan. Different kinds of anesthesia have been practiced and reported in these surgeries. We made a survey of anesthetic methods in twelve medical centers and regional hospitals of the island. It was found out that the choice of the anesthesia was mainly dependent on the mutual trust and the full communication between the anesthesiologist and the surgeon, both based on their skills and the operative methods chosen by the surgeon. Single-lumen endotracheal tube with general inhalation anesthesia is practiced in most of the hospitals surveyed. Sevoflurane and desflurane are the choices of the inhalational anesthetic agents. In short, the anesthesiologists tend to practice the type of anesthesia that is simple but safe enough to secure the airway of the patient throughout the thoracoscopic sympathetic surgery.

Coupled effects of treated effluent irrigation and wetting-drying cycles on transport of triazines through unsaturated soil columns

The physical and chemical parameters controlling the movement of atrazine (6-chloro-N2-ethyl-N4-isopropyl-l,3,5-triazine-2,4-diamine; 98.8%) and prometryn [N,N'-bis(1-methylethyl)-6-(methylthio)-l,3,5triazine-2,4-diamine; 99.5%] were investigated in columns infiltrated with treated effluent under unsaturated transient conditions and subjected to drying events at 22 or 60 degrees C followed by rewetting. Three soils varying in soil pH and texture and three solutions were used. The infiltrating solutions consisted of either a CaCl2 matrix (CC), a swine waste-derived lagoon effluent (SW), or a simulated buffer solution (SB) representative of the element composition and pH of the SW but with no dissolved organic matter. Several parameters were monitored including leachate triazine concentrations, pH, dissolved organic carbon (DOC), inorganic carbon, and flow rates. Compared with CC, application of SW and SB increased column leachate pH, enhanced dissolution of organic carbon and particle dispersion, and decreased average flow rates, which allowed for increased desorption time. The coupled effect of these processes enhanced movement of triazines in some cases, with SW generally having the greatest effect. The individual effect of increased pH was more pronounced for prometryn (pKa=4.05) versus atrazine (pKa=1.66), and most dramatic for the soil with the lowest initial pH. High-temperature drying, which simulated intensive evaporation, further enhanced the dissolution of soil organic matter and the reduction in leachate flow rates with SW and SB applications; however, the net effect under the experimental conditions employed varied with soil type. Relative to low-temperature drying, high-temperature drying in the silty clay loam-packed columns reduced pesticide migration.

Human Ca2+/calmodulin-dependent protein kinase kinase beta gene encodes multiple isoforms that display distinct kinase activity

Ca(+2)/calmodulin-dependent protein kinases (CaMKs) are activated upon binding of Ca(+2)/calmodulin. To gain maximal activity, CaMK I and CaMK IV can be further phosphorylated by an upstream kinase, CaMK kinase (CaMKK). We previously isolated cDNA clones encoding human CaMKK beta isoforms that are heterogeneous in their 3'-sequences (Hsu, L.-S., Tsou, A.-P., Chi, C.-W., Lee, C.-H., and Chen, J.-Y. (1998) J. Biomed. Sci. 5, 141-149). In the present study, we examined the genomic organization and transcription of the human CaMKK beta gene. The human CaMKK beta locus spans more than 40 kilobase pairs and maps to chromosome 12q24.2. It is organized into 18 exons and 17 introns that are flanked by typical splice donor and acceptor sequences. Two major species of transcripts, namely the beta1 (5.6 kilobase pairs) and beta2 (2.9 kilobase pairs), are generated through differential usage of polyadenylation sites located in the last and penultimate exons. Additional forms of CaMKK beta transcripts were also identified that resulted from alternative splicing of the internal exons 14 and/or 16. These isoforms display differential expression patterns in human tissues and tumor-derived cell lines. They also exhibit a distinct ability to undergo autophosphorylation and to phosphorylate the downstream kinases CaMK I and CaMK IV. The differential expression of CaMKK beta isoforms with distinct activity further suggests the complexity of the regulation of the CaMKK/CaMK cascade and an important role for CaMKK in the action of Ca(+2)-mediated cellular responses.

Role of pH in partitioning and cation exchange of aromatic amines on water-saturated soils

Predicting the reversible interactions between aromatic amines and soil is essential for assessing the mobility, bioavailability and exposure from contaminated sites. Reversible sorption mechanisms of aniline and alpha-naphthylamine were investigated by using single and binary solute sorption to five soils at several pH values, and by applying a distributed parameter (DP) model. The DP model assumes linear partitioning of the neutral species into soil organic matter domains and organic cation binding on negative-charged sites with the exchange coefficients represented by a Gaussian probability distribution. Sorption nonlinearity was attributed to cation exchange with varying site affinities, which was adequately simulated using the DP model. Greater uptake by hydrophobic partitioning and selectivity for cation exchange sites was observed for alpha-naphthylamine compared to aniline. Sorption of alpha-naphthylamine was not impacted quantitatively by aniline under those conditions examined; however, aniline sorption was reduced by alpha-naphthylamine with the largest reduction occurring in the soil with the lowest pH. DP model simulations showed that although hydrophobic partitioning increases with soil-solution pH, cation exchange still contributes significantly to the total sorption even at soil-solution pH values greater than pKa + 2.

Effects of dissolved organic matter from animal waste effluent on chlorpyrifos sorption by soils

The increased use of animal waste-derived effluents for irrigation could result in the enhanced movement of pesticides through complexation with dissolved organic materials. Batch equilibrium studies were conducted to measure the interaction among soil, chlorpyrifos [O,O-diethyl O-(3,5,6-trichloro-2-pyridyl) phosphorothioate], and dissolved organic matter (DOM) from poultry, swine, and cow waste-derived lagoon effluents. All DOM was found to have a strong affinity for chlorpyrifos, resulting in reduced sorption of chlorpyrifos by soil, thus the potential for DOM-enhanced mobility. Effluent DOM was observed to sorb to soils. Thus, for increasingly higher soil mass to solution volume ratios, the effect of chlorpyrifos association with water-borne DOM on sorption decreases significantly. For high soil mass to solution volume ratios typical of soil profiles in the landscape, the potential for DOM-enhanced transport will be greatly attenuated. Dissolved organic matter concentration and the nonpolar nature of DOM in the lagoon effluent decreased with increasing residence time in the cells of the lagoon system, thus reducing the potential for DOM-enhanced transport.

A metastatic pituitary carcinoid tumor successfully treated with gamma knife radiosurgery

Intracranial metastasis occurs in a certain number of patients with carcinoid tumor. However, carcinoid tumor with metastasis to the pituitary gland is extremely rare. Up to the present, no effective treatment for either a metastatic intracranial carcinoid tumor or a metastatic pituitary lesion of any origin has been documented. We have treated a case of metastatic carcinoid tumor of the pituitary gland with transsphenoidal tumor resection followed by gamma knife radiosurgery. A 59-year-old man presented with headache and left oculomotor palsy. He was treated at the same hospital for bronchial atypical carcinoid tumor one and a half years ago. Magnetic resonance image of the brain showed a pituitary tumor. There were no signs of recurrent or metastatic lesion elsewhere despite thorough investigation. Transsphenoidal approach for removal of tumor was done and the pathology turned out to be a metastatic carcinoid tumor. Subsequent gamma knife radiosurgery was given for residual tumor. The oculomotor palsy improved after radiosurgery. No neurological deficit occurred. Follow-up CT scan of the brain showed complete resolution of the tumor. We concluded that gamma knife radiosurgery could be used to treat a metastatic intracranial carcinoid tumor. It can also be used to treat a metastatic lesion of the pituitary gland without causing neurological deficit.

Modeling competitive cation exchange of aromatic amines in water-saturated soils

Competitive association to several components of soil through ion exchange processes influences the fate of organic cations in the environment. To examine these processes, the distributions of aniline and 1-aminonaphthalene between aqueous 5 mM CaCl2 solutions and three different Indiana soils were evaluated. Solute ratios (Sr) of aniline to 1-aminonaphthalene of 0.4-4.7 were employed, and the soil solutions ranged in pH from 2.7 to 7.5, with all measurements made 24 h after the introduction of the chemicals to the soils. Two previously proposed equilibrium models--the two-site (TS) and distributed parameter (DP) models--were modified to predict competition. These models assume instantaneous equilibrium of the following reversible processes: (i) acid dissociation of the protonated organic base (BHaq+) in the aqueous phase; (ii) ion exchange on the soil between the protonated organic base and inorganic divalent cations (Daq2+ = Caaq2+ + Mgaq2+); and (iii) partitioning of the nonionic species of aniline (Baq) to soil organic carbon. The TS model is a general mass action model that does not take into consideration cation exchange site heterogeneity, whereas the DP model considers association constants to these sites to be distributed in a log-normal fashion. To describe competition for cation exchange sites within the DP model, it was necessary to add a correlation coefficient (rho) that relates the ion-exchange association constant (KBH) probability density distribution functions of the two compounds. The value of rho is characteristic of each soil. Results indicate that competition has a greater effect at low pH values, where ion exchange is the predominant process. For all cases, these models capture the general trends in the soil-water distribution data of both amines. The DP model also captures the nonlinearity of the 1-aminonaphthalene isotherms at low pH while at the same time capturing the nearly linear isotherms of aniline as a competing organic base.

Microsurgical treatment of deep arteriovenous malformations--basal ganglia and thalamus

BACKGROUND

Surgery for deep nuclei arteriovenous malformations (AVMs) is controversial after the introduction of stereotactic irradiation and embolization. However, rupture of an AVM in this location can lead to catastrophic parenchymal or intraventricular hemorrhage. Thus, microsurgery still has its place in treatment of such lesions to prevent the untreated AVM bleeding or rebleeding. We present a series of 16 AVMs located in the deep nuclei treated by direct microsurgery before radiosurgery was available in 1993.

METHODS

We reviewed the clinical and angiographic characteristic of 16 patients with deep-seated AVMs (three in caudate nucleus, three in lentiform nucleus and ten in thalamus). The surgical approach was described separately depending upon the location of the AVMs. The surgical outcomes were classified as excellent (symptoms improved), good (no additional neurological deficit), fair (minor neurological deficit), bad (major neurological deficit) and dead.

RESULTS

Complete AVM elimination was achieved in 16 patients (100%) in one-stage operation. Eleven patients had excellent or good outcomes, three had fair outcomes and two had bad outcomes. There were no deaths in this series. Two patients had permanent hemiparesis to make a late morbidity rate of 12.5%.

CONCLUSIONS

With improving microsurgical techniques, neuroimaging and neuroanesthesia, difficult and deeply hidden AVMs can be successfully resected under microsurgery with an acceptably low morbidity and mortality rate.

Genetic risk factors of sporadic Alzheimer's disease among Chinese in Taiwan

To evaluate the genetic factors for AD among a Chinese population in Taiwan, we studied the polymorphisms of six candidate genes of Alzheimer's disease (AD), including the regulatory region of apolipoprotein E (Apo-E, G-186T), the promoter of apolipoprotein E (Apo-E, A-491T), the bleomycin hydrolase gene (BH, A1450G), a mutation of alpha(2)-macroglobulin gene (A2M G2998A), low-density lipoprotein receptor-related protein gene (LRP, C766T), and alpha(1)-antichymotrypsin gene (ACT, -15Ala/Thr) in AD patients and non-affected elder individuals among Taiwanese Chinese. Eighty-two AD patients and 110 non-affected individuals were recruited for this study. We used polymerase chain reaction (PCR) and restriction enzyme digestion to identify their genotypes. The statistical examination was performed by combining the results of our previous reports - apolipoprotein E epsilon4 (ApoE-4), presenilin-1 intronic polymorphism (PS-1, allele 1/2), and the five-nucleotide deletion of alpha(2)-macroglobulin gene (A2M). Among these nine candidate genes of AD, the ApoE-4 allele is the only independent genetic risk factor for AD. The other candidate genes in this study were not associated with the occurrence of AD. In addition, there are no gene-gene interactions.

Analysis of grape ESTs: global gene expression patterns in leaf and berry

Analysis of 2479 ESTs from Vitis vinifera berry tissue and 2438 from leaf revealed that 1% of the ESTs match to known Vitis proteins, 72% to plant proteins, 11% to non-plant, and 16% had no match (P[N]>0.5). The levels of redundancy were similar in the leaf and berry libraries. Only 12% of the genes matched by the ESTs were common to both libraries indicating marked differences in the genes expressed in the two tissues. The abundance of transcripts with predicted cellular roles in leaf and berry were estimated by classifying the primary BLAST matches to known proteins (score >80) into functional categories. Thirty-six percent of the leaf transcripts were involved in photosynthesis, compared to 3% in the berry. This is a much higher proportion of transcripts involved with a function limited to specialized cells, than was found when transcripts of 33 human tissues were compared using a similar approach, suggesting plant cells may involve their cellular machinery to a greater extent in specialized activities than animal cells. Relatively enhanced expression of specific transcription factors, and genes involved in defense, detoxification, stress response, proteolysis, trafficing, and signal transduction, suggests berry tissue is actively engaged in responding to environmental stimuli.

Elevated levels of urine angiostatin and plasminogen/plasmin in cancer patients

Previously, a specific angiogenesis inhibitor, angiostatin, discovered in urine and serum of tumor-bearing mice, was reported to potently block tumor growth and metastasis in animal models. Detection of angiostatin and its precursor proteins in urine from cancer patients has not been reported. Now, we report the development of an antibody-based analysis system that allows us to detect angiostatin and plasminogen/plasmin (Pgn/plasmin) in the urine of cancer patients. The detection system is a combination of a novel lysine-ELISA assay and Western immunoblot analysis using a specific antibody to human angiostatin and Pgn/plasmin. High levels of Pgn/plasmin were detected in the urine from various cancer patients, whereas healthy individuals showed relatively low levels of urine Pgn/plasmin. Of interest, angiostatin is detectable in urine samples of patients with various cancers, including acute lymphoblastic leukemia, suggesting that angiogenesis may play an important role in the development and progression of leukemia. Our data for the first time show that angiostatin and Pgn/plasmin are present at relatively high levels in the urine of human cancer patients. Detection of urine angiostatin in cancer patients helps us not only to understand the role of this angiogenesis inhibitor in cancer development and progression but also allows us to develop tools of cancer diagnosis and prognosis. Thus angiostatin has both therapeutic and diagnostic implications in cancer disease.

Far lateral lumbar disc herniation

BACKGROUND

Far lateral lumbar disc herniation is an uncommon condition that may compress the nerve root outside the vertebral canal and in its extraforaminal course. The traditional midline interlaminar approach for the exploration of far lateral lumbar disc herniation is often difficult because the intervertebral articulation obviates a direct view of the course of the extraspinal nerve. In this report, we present two surgical approaches for the treatment of far lateral lumbar disc herniation: the paramedian muscle-splitting microtechnique and the enlarged midline approach.

METHODS

Eight patients with far lateral lumbar disc herniation were found among 160 lumbar disc operations in 160 patients. According to computed tomography results, we divided patients with far lateral lumbar disc herniations into two groups; the extraforaminal and foraminal groups. Clinical presentation, imaging studies and surgical approach were thoroughly reviewed.

RESULTS

Three patients in the extraforaminal group underwent the paramedian muscle-splitting microtechnique. Two patients in the foraminal group underwent the enlarged midline approach. The other three were operated on before the introduction of the paramedian muscle-splitting microtechnique and the enlarged midline approach. One of these patients who underwent the traditional interlaminar approach with resection of the lateral portion of facet joint, received additional instrumentation and fusion for the prevention of further instability. All had good results and no further surgical treatment was necessary.

CONCLUSIONS

The incidence of far lateral lumbar disc herniation was 5% of all surgically treated disc herniations at our institution. For the extraforaminal group, the paramedian muscle-splitting microtechnique is the surgical route of choice. For the foraminal group, the enlarged midline approach is better than the traditional, interlaminar approach in saving the facet joint and preventing postoperative instability.

Membranous occlusion of the foramen of Monro following ventriculoperitoneal shunt insertion: a role for endoscopic foraminoplasty

We report two cases of lateral ventricle dilatation due to membranous occlusion of the foramen of Monro following ventriculoperitoneal shunt insertion. Both cases were treated successfully by endoscopic foraminoplasty of the obstructed foramen of Monro and III ventriculostomy. One child had meningomyelocele and hydrocephalus. She had CSF infection after repair of the back lesion. Isolated left lateral ventricle occurred after insertion of a right ventriculoperitoneal shunt for hydrocephalus when the girl was 2 months old. A right ventriculoperitoneal shunt was then inserted. Chronic shunt infection with abdominal pseudocyst was found 8 years later. The shunts were exteriorized. Membranous obstruction of the foramen of Monro was found endoscopically. Fenestration of the membranous obstruction along with a III ventriculostomy was performed. After the endoscopic procedure, the exteriorized ventriculoperitoneal shunt was removed 2 weeks later. The patient was still symptom free without shunting 14 months after the operation. The other child had hydrocephalus after a premature birth and hemorrhage. Repeated ventriculoperitoneal shunt infections contributed to membranous obstruction of bilateral foramen of Monro. After the shunt infection was treated this patient's shunting procedure was simplified by endoscopic foraminoplasty of the left and right foramen of Monro along with a III ventriculostomy. He was symptom free with a new ventriculoperitoneal shunt 9 months after the operation.

Field and numerical analysis of in-situ air sparging: a case study

An in-situ air sparging operation was used to remediate the sandy subsurface soils and shallow groundwater under a drum storage site near Chicago, IL, where either periodic or random spillage of a light non-aqueous phase liquid (LNAPL) occurred between 1980 and 1987. Both field measurements and model simulations using commercially available computer software suggested that microbial degradation was the most significant contributor to the removal of contaminant mass. Toluene, ethylbenzene and total xylenes (TEX), which were of major concern with regards to reaching clean-up criteria at the site, were observed to decline by 88% in concentration. Furthermore, up to 97% of the total mass removed through microbial degradation consisted of TEX. Of the total contaminant spill, up to 23% of initial organic chemical mass was removed through microbial degradation compared to less than 6% by physical stripping. Greater loss to microbial degradation is most likely attributed to the relatively low air injection rate used during the course of the air sparging remediation. Evaluation of air sparging at the site using model simulations supported this analysis by estimating 140 and 620 kg of total contaminant mass being removed through volatilization and biodegradation, respectively. An evaluation of several system design parameters using model simulations suggested that only the type of sparging operation (i.e. pulsed or continuous) was significant in terms of total contaminant removal time, while both the sparging operation and air injection rate were significant in terms of removal of a critical species, total xylenes.

Anterior cervical stabilization with the synthes cervical spine locking plate system

BACKGROUND

The Synthes cervical spine locking plate (CSLP) was originally designed by Mörscher and colleagues, who refined it to prevent the migration and loosening of a locking screw by using a cross-split screw head that could be locked into the plate. This eliminated the requirement of the posterior cortex purchase and thereby decreased the risk of spinal cord injury. The purpose of this report is to review our experience using the cervical spine locking plate system and to evaluate its ability to stabilize the cervical spine.

METHODS

Twenty patients with cervical trauma, cervical spondylosis of failed anterior interbody fusion underwent anterior cervical fusion with the Synthes CSLP system between August, 1993, and April, 1996. All patients were evaluated preoperatively and postoperatively by plain radiography and magnetic resonance imaging (MRI).

RESULTS

All 20 patients achieved solid bone fusion and 19 of them had neurologic improvement, by a mean follow-up period of 36 months. No patients suffered from neurologic injury as a result of the locking device. No patient demonstrated radiologic evidence of implant failure. The postoperative MRI examination disclosed minimal implant artifacts and adequate spinal cord decompression.

CONCLUSIONS

The Synthes CSLP system for anterior stabilization provides efficacy, safety and ease of use. It also caused less distortion and minimal artifacts on postoperative MRI.

Detection of mammosomatotrophs in paraffin-embedded specimens of various pituitary adenomas

BACKGROUND

There are various classification systems for pituitary adenomas based on whether mammosomatotroph cells, which simultaneously express both prolactin (PRL) and growth hormone (GH), can be found. Until the present, the identification of such cells required special techniques and could not be performed in paraffin-embedded specimens. This hindered large-scale studies for detection of mammosomatotrophs in various pituitary adenomas and, as a result, such classification has remained controversial. To establish a methodology for the detection of mammosomatotrophs in paraffin-embedded specimens and to propose a more logical classification for pituitary adenomas, the authors conducted this retrospective study.

METHODS

We performed double immunofluorescence staining of PRL and GH in paraffin-embedded specimens of various pituitary adenomas with subsequent observation with a confocal laser-scanning microscope.

RESULTS

Mammosomatotrophs were found in four of the 10 GH-secreting adenomas and one of the 10 clinically nonfunctioning adenomas. However, mammosomatotrophs were not identified in all 10 cases of prolactinoma.

CONCLUSIONS

This is the first report in the literature that successfully demonstrates the presence of mammosomatotrophs in routine paraffin-embedded pituitary adenomas. The new methodology is important for future study of the function and role of these cells. A large-scale study for mammosomatotrophs in various pituitary adenomas with this method and a more logical classification of pituitary adenomas are proposed.

Intraoperative neurosurgical ultrasonography

BACKGROUND

Ultrasound scanning is a well-established means of evaluating intracranial structures in infants and children with open fontanelles. However, it remains underutilized in neurosurgical operations. We present our experience with the intraoperative use of realtime ultrasonography during 36 neurosurgical procedures.

METHODS

Thirty-six intraoperative ultrasonography (IOUS) procedures were performed over the past two years. Thirty-two patients had intracranial lesions and four had intraspinal tumors. A real-time scanner equipped with a 5 MHz and a 7.5 MHz transducer was used during surgery.

RESULTS

IOUS worked well, regardless of the location of the craniotomy site. It was useful in localizing and characterizing intracranial and intraspinal masses, assuring the completeness of tumor removal (22 cases), proper positioning of ventricular shunt catheters (5 cases), guiding and confirming the decompression of cysts or abscesses (3 cases) and real time monitoring of surgical complications (36 cases).

CONCLUSIONS

IOUS can be helpful in defining intracranial and intraspinal lesions as well as normal architecture. It shortens the operative time and decreases the surgical morbidity. The expertise of the physician with sonographic equipment facilitates its accurate and expedient intraoperative neurosurgical application.

Prolonged circulating lives of single-chain Fv proteins conjugated with polyethylene glycol: a comparison of conjugation chemistries and compounds

The utility of single-chain Fv proteins as therapeutic agents would be substantially broadened if the circulating lives of these minimal antigen-binding polypeptides were both prolonged and adjustable. Poly(ethylene glycol) (PEG) bioconjugate derivatives of the model single-chain Fv, CC49/218 sFv, were constructed using six different linker chemistries that selectively conjugate either primary amines or carboxylic acid groups. Activated PEG polymers with molecular weights of 2000, 5000, 10 000, 12 000, and 20 000 were included in the sFv bioconjugate evaluation. Additionally, the influence of PEG conjugate geometry in branched PEG strands (U-PEG) and the effect of multimeric PEG-sFv bioconjugates on circulating life and affinity were examined. Although random and extensive PEG polymer conjugations have been achievable in highly active derivatives of the prototypical PEG-enzymes, PEGylation of CC49/218 sFv required stringent adjustment of reaction conditions in order to preserve antigen-binding affinity as measured in either mucin-specific or whole cell immunoassays. Purified bioconjugates with PEG:sFv ratios of 1:1 through 2:1 were identified as promising candidates which exhibit sFv affinity (K(d)) values within 2-fold of the unmodified sFv protein. Interestingly, PEG conjugation to carboxylic acid moieties, using a PEG-hydrazide chemistry, achieved significant activity retention in bioconjugates at a higher PEG:sFv ratio (5:1) than with any of the amine-reactive activated PEG polymers. Prolonged circulating life in mice was demonstrated for each of the PEG conjugates. An increase in PEG polymer length was found to be more effective for serum half-life extension than a corresponding increase in total PEG mass. For example, CC49/218 sFv conjugated to either one strand of PEG-20000, or four strands of PEG-5000, displayed about 20- or 14-fold increased serum half-life, respectively, relative to the unmodified sFv. The demonstrated suitability of established random conjugation chemistries for PEGylation of sFv proteins, in conjunction with innovative site-specific conjugation methods, indicates that production of a panoply of sFv proteins with both engineered affinity and tailored circulating life may now be achievable.

Computerized tomography-guided stereotactic aspiration of brain abscesses: experience with 28 cases

BACKGROUND

Computerized tomography (CT)-guided stereotactic techniques allow accurate identification of brain abscesses and provide promising results for the management of brain abscesses.

METHODS

We reviewed the results of stereotactic aspiration of brain abscesses in 28 consecutive patients from 1984 to 1995. In all patients, the diagnosis of brain abscess was made by computerized tomography (CT). All patients underwent stereotactic aspiration of abscesses as the primary surgical therapy. Intravenous antibiotics were administered preoperatively and adjusted according to organism type and sensitivity to antibiotics. In patients with multiple lesions, aspirations were performed on abscesses larger than 2 cm in diameter or on those causing significant mass effects. CT was performed weekly to monitor abscess growth or failure to resolve. Patients were followed on an outpatient basis. This report is a retrospective review of clinical features, diagnostic methods, treatment and postoperative results.

RESULTS

A total of 19 patients had good recoveries and six patients had mild neurologic sequelae. One patient had persistent conscious impairment. Intracranial hemorrhage occurred in one patient. Two deaths occurred during hospitalization. One patient with a fungal infection underwent additional surgical excision of the abscess. Most patients had resolution of abscesses after stereotactic treatment within two months. The cure rate was 92% in patients with bacterial brain abscesses treated with stereotactic aspiration and intravenous antibiotics for six weeks.

CONCLUSIONS

Stereotactic surgery is a procedure with minimal morbidity and mortality, and can be the treatment of choice for brain abscesses when combined with appropriate antibiotic therapy.

Aneurysmal subarachnoid hemorrhage in Taiwan

In 1993, the annual report about prospective survey and registry of stroke revealed there were 439 cases of ruptured intracranial aneurysms in Taiwan area. Thirty-two of them had multiple aneurysms; therefore, totally 476 aneurysms occurred in these cases. The anatomic distribution of these aneurysms were as the following: internal carotid artery-posterior communicating artery 32%, anterior communicating artery 30%, middle cerebral artery 18%, carotid bifurcation 6%, anterior cerebral artery 4%, carotid-ophthalmic artery 2%, intracavernous carotid artery 2%, and vertebrobasilar system 6%. 364 cases received surgical or interventional treatment, which 88% was clipping procedure, 8% was interventional procedure with coil, and 4% was wrapping. The surgical mortality was 13%.

Pilocytic astrocytoma of the posterior fossa: a follow-up study in 15 patients

BACKGROUND

The extent of resection in pilocytic astrocytoma of the posterior fossa remains undefined, as the problem of hydrocephalus has not yet been solved. We retrospectively reviewed the data from 15 patients with a pilocytic astrocytoma of the posterior fossa to evaluate the impact of surgical technique, in terms of resection extent, by serial magnetic resonance imaging (MRI) examinations. In addition, the issue of hydrocephalus was considered and related to the different treatment modalities.

METHODS

Macroscopic, gross, total resection of the tumor was performed in all 15 patients. Follow-up was obtained in 14 patients for a period ranging between 11 and 119 months (median, 41.5 months). The ages of patients ranged from two to 13 years (mean, 7 +/- 3 years). All patients underwent serial MRI examinations in the first month, every six months for the first two years and then yearly.

RESULTS

Outcome was good in 12 patients who had no neurologic deficit and fair in two patients who were slightly handicapped but had an independent life. There were four patients with an abnormally persistent enhancement on MRI, with a median follow-up of 30 months. One of these patients had progressively increasing size of the enhancement. Three of them had the same size of enhancement during the follow-up period. The MRI findings showed residual tumors in four patients. One of them had tumor regrowth one year after surgery. There were 11 cases with pilocytic astrocytoma and hydrocephalus. Five patients were treated with tumor removal and external CSF drainage. Six patients underwent tumor removal only, without perioperative cerebrospinal fluid (CSF) drainage. Only one patient had a permanent ventriculoperitoneal shunt.

CONCLUSIONS

Our study illustrated that the extent of tumor resection of pilocytic astrocytoma can be defined by postoperative serial MRI examinations. Long-term follow-up with MRI seems mandatory in cases with abnormal enhancement. Hydrocephalus is a common finding in patients with a pilocytic astrocytoma. A permanent ventriculoperitoneal shunt is required only in patients with postoperative hydrocephalus.

Microsatellite variation and assessment of genetic structure in tea tree (Melaleuca alternifolia-Myrtaceae)

Analysis of five microsatellite loci in 500 Melaleuca alternifolia individuals produced 98 alleles that were useful for population genetic studies. Considerable levels of observed heterozygosity were recorded (HO = 0.724), with approximately 90% of the variability being detected within populations. A low level of selfing (14%) was suggested to be the principal cause of excess homozygosity in a number of populations (overall FIS = 0.073). This study showed low levels of inbreeding in certain populations as well as a significant isolation-by-distance model. Only two groups of populations (Queensland and New South Wales) constituted different genetic provenances as a result of geographical isolation. The M. alternifolia data suggest that microsatellite loci did not always arise by a stepwise mutation process but that larger jumps in allele size may be involved in their evolution.

Bioequivalence study of two morphine extended release formulations after multiple dosing in healthy volunteers

AIM

Two extended release (ER) formulations of morphine sulphate (30 mg each), Oramorph SR (test) and a marketed reference formulation (MST Mundipharma Retardtabletten), were investigated for their relative bioavailability at steady-state:

METHODS

The study was designed as a single-centre, open-label, two-period crossover, pharmacokinetic comparison in 28 healthy male volunteers and was completed in 23 subjects. The determination of morphine and its metabolite morphine-6-glucuronide in plasma was done by HPLC with electrochemical detection after solid-phase extraction.

RESULTS

Under steady-state conditions in the first dosing interval, mean maximum plasma concentrations for morphine were 19.1 ng/ml (CV% 41) for Oramorph SR 30 mg and 19.1 ng/ml (CV% 33) for MST-30 Mundipharma Retardtabletten. Geometric mean AUC(0-12) values were calculated as 108 ngxh/ml (CV% 40) for Oramorph SR 30 mg and as 118 ng x h/ml (CV% 30) for the reference formulation. The plasma concentrations of the major metabolite, morphine-6-glucuronide, were found to be generally in a higher range compared to the parent compound. The 90% confidence intervals of test to reference ratios calculated for all relevant parameters (AUC, C(max), PTF) for both the parent compound and morphine-6-glucuronide were all within the limits of 80 - 125%. The most frequent adverse events (AE > 10%) during Oramorph SR 30 mg treatment were headache (36%), dizziness (18%), nausea (21%), vomiting (21%) and pruritus (11%). During treatment with MST-30 Mundipharma Retardtabletten, the most frequent AEs were headache (29%), dizziness (13%), nausea (29%) and vomiting (29%).

CONCLUSION

The results demonstrate bioequivalence of Oramorph SR 30 mg and MST-30 Mundipharma Retardtabletten.

Abnormal transcripts of FHIT gene in Chinese brain tumors

FHIT located at chromosome 3p14.2 was discovered and proposed as a candidate tumor suppressor gene in several cancers. To determine whether the FHIT gene at 3p14.2 is altered in Chinese brain tumors, we examined 13 brain tumors for deletions within FHIT locus. Evaluation of the FHIT gene in the panel of brain tumors led to a comprehensive mutation analysis. The complete sequence of the FHIT gene was determined and deletions between exon 5-8 were found in all 13 cases. In addition, single point mutation of amino acid from two glioblastoma and one atypical meningioma cases and multiple amino acid mutations from one pituitary tumor were observed. Our results support the hypothesis that FHIT gene alteration is involved in tumorigenic development of human neoplasms.