Spatial trends and bioaccumulation of organochlorine pollutants in marine zooplankton from the Alaskan and Canadian Arctic

Planktonic copepods (Calanus glacialis and C. hyperboreus; n = 37) and water (n = 19) were collected to examine the spatial distribution and bioaccumulation of organochlorine contaminants (OCs) in the Alaskan and Canadian Arctic. The rank order of total OC (sigma OC) group concentrations in Calanus samples was toxaphene > or = sigma polychlorinated biphenyls (PCBs) > sigma hexachlorcyclohexane (HCH) > sigma DDT > sigma chlordane-related compounds (CHLOR) > sigma chlorobenzenes (ClBz). The dominant analyte was alpha-HCH in all water and zooplankton samples. The most abundant toxaphene congener in water and zooplankton samples was the hexachlorobornane B6-923. Organochlorine contaminant group concentrations in Alaskan zooplankton and water samples were lower than those in samples collected from sites in the eastern Canadian Arctic. Comparison of PCB and toxaphene congener profiles in zooplankton and water samples suggests that biotransformation by cytochrome P-4502B isozymes is low in Calanus, and limited phase I metabolism may occur. The log relationship of bioaccumulation factor (log BAF) versus octanol-water partition coefficient (log Kow) relationship was near 1:1 for OCs within the log Kow range of 3 to 6. A curvilinear model provided a better relationship between these two variables when OC compounds with log Kow > 6 were included. These results suggest that hydrophobic OCs (log Kow 3-6) in Calanus species are at equilibrium with the water concentrations and that physical partitioning, rather than biotransformation, is the major factor governing OC profiles in marine zooplankton.     

Reproducibility and clinical value of 18F-fluorodeoxyglucose positron emission tomography in recurrent melanoma

The purpose of this study was to assess the reproducibility and clinical impact of positron emission tomography (PET) with 18F-fluorodeoxyglucose (FDG) in patients with (suspected) recurrent melanoma. The clinical value of PET was prospectively measured in 58 consecutive patients referred for PET because of unresolved clinical questions after conventional work-up. Diagnostic understanding and therapy choice by referring physicians were evaluated before, directly after, and 6 months after PET. Observer agreement of PET readings was measured with respect to various parameters (interpretation, number and localization of lesions, 'clinically decisive' metastases), using intra-class correlation coefficients. FDG PET improved diagnostic understanding in 33 cases (57%). In six patients (10%), diagnostic understanding was solely based on PET information. According to the attending clinicians, PET contributed to a positive change of planned treatment in 23 patients (40%) and increased confidence in the chosen treatment in 23 (40%). Observer agreement of PET readings was very high (intra-class correlation coefficients were between 0.87 and 0.94). The diagnostic value related especially to the whole-body scan technique and the superior specificity, compared to conventional work-up. It is concluded that, in problematical cases with (suspected) recurrent melanoma, 18F-FDG PET had considerable impact on diagnostic understanding and management. Together with the excellent observer reliability, these results justify further studies to determine the optimal place of PET in routine diagnostic algorithms in recurrent melanoma.     

难治性青光眼两种治疗方法的比较

临床资料 2003-02／2004—10，难治性青光眼36例36眼，(男19，女17)例；年龄37—81(平均59．6)岁；术前视力：无光感6例，光感15例，手动13例，眼前数指2例；术前眼压：在5．59—10．77(平均8．01)kPa；1例系玻切术后继发性青光眼，35例系新生血管性青光眼(其中：视网膜静脉阻塞15例，糖尿病视网膜病变18例，原因不明2例)．①眼内窥镜下睫状体光凝术18例：在角膜缘环形剪开结膜，充分止血；在     

Monitoring of response to pre-operative chemoradiation in combination with hyperthermia in oesophageal cancer by FDG-PET.

PURPOSE: To evaluate the use of positron emission tomography using 18F-fluorodeoxyglucose (FDG-PET) to assess early response to pre-operative chemoradiation therapy in combination with external locoregional hyperthermia in patients with oesophageal cancer by correlating the reduction of metabolic activity with histopathologic response. MATERIAL AND METHODS: Twenty-six patients with histopathologically proven intra-thoracic oesophageal cancer (with < or =2 cm gastric involvement), scheduled to undergo a 5-week course of pre-operative chemoradiation therapy and hyperthermia, were included. FDG-PET was performed before (n = 26) and 2 weeks after initiation of therapy (n = 17). FDG uptake was quantitatively assessed by standardized uptake values. RESULTS: After neoadjuvant therapy, 24 of the 26 patients underwent surgery. In 16 patients changes in FDG uptake were correlated to histopathologic response. In these patients, histopathologic evaluation revealed less than 10% viable tumour cells in eight patients (responders) and more than 10% viable tumour cells in eight patients (non-responders). In responders, FDG uptake decreased by a median -44% (-75 to 2); in non-responders, it decreased by a median of -15% (-46 to 40). At a threshold of 31% decrease of FDG uptake compared with baseline, sensitivity to detect response was 75%, with a corresponding specificity of 75%. The positive and negative predictive values were both 75%. CONCLUSION: FDG-PET is a promising tool for early response monitoring in patients undergoing chemoradiation therapy in combination with hyperthermia.     

Routine chest X-rays have no additional value in the detection of relapse during routine follow-up of patients treated with chemotherapy for disseminated non-seminomatous testicular cancer.

BACKGROUND: The routine follow-up of patients with disseminated non-seminomatous testicular cancer (DNSTC) treated with the combination of orchidectomy, polychemotherapy, and if needed, resection of the residual mass, consists of regular physical examinations, chest X-rays (CXR) and tumor marker assessments. Most guidelines for this routine follow-up originate from multi-center trials. In order to estimate the value of CXR in the detection of tumor relapse after complete remission, we reviewed all patients with disseminated testicular cancer treated with chemotherapy at the University Hospital Groningen. PATIENTS AND METHODS: Three hundred and fifty-three consecutive patients with DNSTC treated between February 1977 and February 1999 at our institution were reviewed. Two hundred and ninety (82.2%) patients, who were in complete remission after cisplatin-containing chemotherapy followed by, if necessary, resection of the residual mass, entered this analysis. The follow-up schedule consisted of regular physical examinations, tumor marker assessment (lactate dehydrogenase, beta-human chorionic gonadotropin and alpha-FP) and CXR. In all patients the first diagnostic sign of tumor relapse was documented. RESULTS: During a median follow-up of 107 months (range 8-261) a tumor relapse was documented in 33 patients (11.4%). Median time to relapse was 17 months (range 6-179) after the start of chemotherapy. In 27 patients, tumor relapse was first detected by a rise in tumor markers. Two patients presented their relapse with neurological complaints. Both were diagnosed with brain metastasis. In four patients the relapse was detected by both increase in tumor markers and abnormalities in the physical examination. In none of the 33 relapsed patients was routine CXR during follow-up involved in the detection of tumor recurrence. All but one of the relapsed patients had elevated tumor markers before the start of chemotherapy. The total number of CXR made during follow-up in all 290 patients was 10 160; none were diagnostic for the detected relapses. CONCLUSIONS: These data suggest that routine CXR has no additional value in the detection of tumor relapses during follow-up after chemotherapy in the subset of patients who present their DNSTC with increased tumor markers and are in complete remission after treatment. In order to save valuable resources, CXR can be omitted from the follow-up schedule after chemotherapy for marker-positive non-seminomatous testicular cancer in complete remission.     

Innervation of supporting cells in the apical turns of the guinea pig cochlea is from type II afferent fibers

The outer supporting cells in the apical turns of the guinea pig cochlea receive a dense innervation. Our previous study (Fechner et al. [1998] J. Comp. Neurol. 400:299-300) suggested that this innervation of the Deiters' and Hensen's supporting cells was not derived from efferent fibers of the olivocochlear bundle, but its origin has not been further specified. To test the hypothesis that the innervation was afferent in origin, we traced apical afferent fibers that were retrogradely labeled by extracellular injections of horseradish peroxidase. Labeled afferent fibers were of two types: type I fibers contacted inner hair cells, whereas type II fibers crossed the tunnel and contacted outer hair cells. Significantly, most of the type II fibers also formed branches to the outer supporting cells. Although a few olivocochlear efferent fibers formed such branches, counts indicated that the overwhelming majority of the branches were produced by type II afferent fibers. These branches were not produced by basal type II fibers. Apical type II fibers also differed from basal fibers by having shorter lengths, spiraling both apically and basally, and contacting all three rows of outer hair cells. These innervation differences suggest differences in the ways that information from outer hair cells is processed in the apex versus the base of the cochlea.     

Bilateral chronic conjunctivitis and corneal scarring in a boy with X-linked hypogammaglobulinaemia

ABSTRACT We report an unusual case of bilateral chronic conjunctivitis and corneal scarring in a boy with X-linked hypogammaglobulinaemia (XLH) who did not respond to the usual antibacterial and antiviral therapy. An immunofluorescence test for Chlamydia trachomatis from an eye swab was strongly positive. Within days of commencement of local and systemic tetracycline therapy, he showed marked improvement. Since conjunctival follicle formation, which depends on the presence of a B-cell population, may not occur in XLH, clinical examination in chlamydia conjunctivitis may be misleading and lead to a delay in diagnosis and treatment with resulting corneal complications, unless laboratory evidence of chlamydia infection is specifically sought.     

Health care and its costs for children with perinatally acquired HIV infection

Objective : To describe survival patterns, use of health services and related costs for Australian children with perinatally acquired human immunodeficiency virus (HIV) infection.
Methodology : A retrospective cross-sectional survey was made of 20 children with HIV infection (91% of those diagnosed) and 13 children with maternal antibodies who subsequently seroreverted, treated at 10 medical centres. Details of disease progression and use of health services were obtained from hospital medical records. Monthly costs for three phases of infection were estimated by linking service usage rates with estimates of the unit cost of each service. The average lifetime cost was estimated by combining monthly costs and phase duration estimates from the literature.
Results : Patterns of disease progression were similar to those reported internationally, with a median survival of 8 years. Use, of health services increased with severity of illness. Mean monthly costs were $120 per month (1992 Australian dollars) for children with maternal antibodies who subsequently seroreverted, $320 per month for children with HIV infection but no acquired immunodeficiency syndrome (AIDS)-defining illness, and $1830 per month for children with AIDS. The present value of total lifetime cost for a child with HIV infection was $48174,46% of which was for treatment of AIDS.
Discussion : The mean lifetime cost for a perinatally infected child was just over half that for a man with HIV in Australia. Health service usage and costs were lower for Australian than American children with HIV.