Positron emission tomography in oncology

Summary. The particular advantages of positron emission tomography (PET) technique are that it has higher sensitivity, higher resolution, and a higher quality of image than that found in conventional nuclear medicine. The possibility of quantification and the wide range of useful tracers have raised expectations of this new method. To date, most of the human PET cancer studies have been performed with [¹⁸F]fluorodeoxyglucose (FDG) or [¹¹CJmethionine. These are good imaging agents for tumours. However, more specific radiopharmaceuticals are required if other features of tumour metabolism are to be observed, f¹¹Thymidine may prove to be a good tracer for quantitative measurements of tumour proliferation and [¹⁸F]misonidazole has been suggested for imaging of hypoxia.     

HCVRNA阳性的丙型肝炎诊断和治疗探讨

HCVRNA阳性的丙型肝炎46例，均经临床和／或组织学确诊。治疗组24例用IFNa－nl或a－2b3×106IU，隔日一次；对照组22例用一般护肝药物。HCVRNA12周转阴率治疗组为83．3％，对照组为9．0％（P＜0．001）。ALT和AST复常率治疗组也优于对照组（P＜0．05）。随访观察满48周者治疗组15例中HCVRNA持续转阴11例（73．3％）．对照组5例均持续阳性。治疗组中5例做了Ⅰ～Ⅲ型HCV基因分型，结果均为Ⅱ型。同时对急、慢性丙型肝炎的发病过程和病理诊断作了讨论。     

Protein C concentrate prevents peripartum thrombosis.

A protein C deficient woman, with a past history of recurrent thrombosis and purpura fulminans, was successfully treated with protein C concentrate in the peripartum period. © 1992 Wiley-Liss, Inc.     

Opioid binding in DYT1 primary torsion dystonia: an 11C-diprenorphine PET study.

The opioid transmitters enkephalin and dynorphin are known to regulate pallidal output and consequently cortical excitability. Indeed, abnormal basal ganglia opioid transmission has been reported in several involuntary movement disorders, including levodopa-induced dyskinesias in Parkinson's disease (PD), tardive dyskinesias/dystonia, Huntington's disease, and Tourette's syndrome. Moreover, a previous 11C-diprenorphine PET study investigating levodopa-induced dyskinesias found reduced opioid receptor availability in PD with but not without dyskinesias. We wished to investigate if a similar alteration in basal ganglia opioid binding was present in DYT1 primary torsion dystonia (PTD). Regional cerebral 11C-diprenorphine binding was investigated in 7 manifesting carriers of the DYT1 gene and 15 age-matched normal controls using a region-of-interest (ROI) approach and statistical parametric mapping (SPM). No difference in regional mean 11C-diprenorphine binding was found between DYT1-PTD and controls, and no correlation between the severity of dystonia and opioid binding was seen. We conclude that aberrant opioid transmission is unlikely to be present in DYT1-PTD and altered opioid transmission is not a common mechanism underlying all disorders of involuntary movement.     

PRKCG mutation (SCA-14) causing a Ramsay Hunt phenotype.

Progressive myoclonic ataxia, also referred to as Ramsay Hunt syndrome, is characterized by a combination of myoclonus and cerebellar ataxia, infrequently accompanied by tonic-clonic seizures. Its differential diagnosis overlaps with progressive myoclonic epilepsy, a syndrome with myoclonus, tonic-clonic seizures, progressive ataxia and dementia. In patients with progressive myoclonic epilepsy, specific diseases can frequently be recognized, but the diagnostic yield in progressive myoclonic ataxia is much lower. We describe a patient who presented with multifocal myoclonus in his thirties and who later developed cerebellar ataxia and focal dystonia. His father was similarly affected. Genetic studies revealed a mutation in the protein kinase C gamma (PRKCG) gene, known to cause spinocerebellar ataxia type 14 (SCA-14). This case illustrates that both myoclonus and dystonia are part of the clinical spectrum in SCA-14 and that myoclonus can even be the presenting symptom. We suggest that SCA-14 should be considered in the differential diagnosis of progressive myoclonic ataxia.     

Prevalence of hepatitis C virus antibody in an area endemic for hepatitis B virus and human T cell leukaemia virus

To clarify the prevalence of concurrent infection with hepatitis C virus (HCV), hepatitis B virus (HBV) and human T cell leukaemia virus (HTLV), we measured HCV antibody in the population of a district endemic for HBV and HTLV infection. Blood samples were collected in June 1990 from 579 inhabitants of four islands of Uwa Bay in the southwest of Ehime Prefecture in Japan. Anti-HCV antibody against C100-3 protein was detected using an enzyme-linked immunosorbent assay kit (Ortho Diagnostics). Thirteen of the 579 inhabitants (2.2%) were positive for anti-HCV, and this prevalence rate was not significantly different from the frequency of anti-HCV in Tokyo blood donors. A total of 11% (64 of 579) of the subjects were positive for HBsAg and 3.3% (19 of 579) were positive for anti-HTLV. These frequencies of HBsAg and anti-HTLV positivity were distinctly higher than the respective means of Japanese. All anti-HCV positive individuals were negative for HBsAg and anti-HTLV, while 54% (7 of 13) had increased alanine aminotransferase levels. These data suggest that the prevalence of HCV infection is not high even in an area endemic for HBV and HTLV infection.     

Fabricating fixed partial dentures using existing restorations

A technique has been described for utilizing an existing fixed splint in the fabrication of a fixed partial denture to replace splinted teeth that are extracted.     

Stereoselective synthesis of radiolabelled avermectins

The natural products avemectin B _1a 1a and B _1b 1b were each site‐specifically ¹⁴C labelled at carbon 23 in a convergent synthesis for metabolism, residue, and environmental studies. The 12‐step radiosynthesis involved a stereoselective aldol condensation and later a coupling to a protected avermectin degradate 2 in a one‐pot Wittig condensation/spiroketalization to reconstitute the dioxaspirane configuration found in the natural products. Copyright © 2004 John Wiley & Sons, Ltd.