The staging and treatment of epithelial ovarian cancer.

Recent advances in the staging of ovarian cancer have suggested that many patients with apparently localized (stage I or II) disease have occult dissemination within the abdomen. Approximately 20% of patients classified at laparotomy as having stage I or II ovarian cancer are found by lymphangiography to have abnormal retroperitoneal lymph nodes. In many other patients advanced disease is also detected by peritonescopy; with this technique metastases are often discovered on the undersurface of the right diaphragm. These findings may help explain the high rates of recurrence after surgical resection or pelvic irradiation, or both, in patients with localized disease. Studies are in progress to determine whether modification of the radiotherapy field to include the right diaphragm will improve survival. Along with improved staging, histologic grading of the degree of anaplasia of the tumour tissue may permit more precise determination of prognosis and therefore better design of therapy. Adjuvant radiotherapy has not yet been shown to improve the survival of patients with stage I disease, but the 5-year survival of patients with stage II disease is greater for those receiving postoperative radiotherapy than for those undergoing surgery alone. For most patients with advanced disease radiotherapy is palliative only and carries a high risk of long-term complications. Numerous chemotherapeutic agents used singly can produce an objective response by tumour. Preliminary data suggest that combination chemotherapy can increase the rate of objective response, but a longer follow-up period is necessary to determine whether this form of therapy can improve survival.     

Rallinyssus sorae sp. n. (Acari: Dermanyssidae: rhinonyssinae) from the nasal passages of the sora, Porzana carolina (Aves: Rallidae)

Rallinyssus sorae sp. n. is described from the nasal turbinates of the sora, Porzana carolina, collected in Maryland and Ohio. The new species is most similar to Rallinyssus verheyeni Fain but differs in number of setae on the female ventral opisthosoma, structure of the fixed and movable digits of the male and female chelicerae, chaetotaxy of legs I to IV, and presence of a sternal plate in the male. The taxonomy and host-parasite relationships of the various species of Rallinyssus are discussed.     

Effectiveness of out-of-hours biochemistry investigations.

A survey was carried out of doctors who used their out-of-hours biochemistry service to find out why requests for investigations were made, how often the results altered patient management, and whether they could define areas where investigations were unproductive. Of 107 questionnaires distributed, 147 (88%) were completed. In 86% the requests were for diagnosis or immediate patient management and in 35% the results actually altered management. Senior clinical staff were more efficient than their juniors in instigating biochemical investigations that proved to be effective. In no instance where the clinical staff predicted that it was unlikely that the results would alter management was management altered. It is suggested that joint reviews of case notes by junior and senior clinical staff would prove to be the most appropriate way to increase the effectiveness and efficiency of clinical investigation.     

Effect of inhibitors of elongation factor Tu on the metabolic regulation of protein synthesis in Escherichia coli.

By using inhibitors of elongation factor Tu (L-1-tosylamido-2-phenylethyl chloromethyl ketone [TPCK] and kirromycin), we determined the effect of elongation factor Tu inhibition on the synthesis of individual components of the translation machinery. The rates of synthesis of individual proteins were measured in double-label experiments using a two-dimensional gel system. TPCK inhibition produce a coordinate decrease in the differential synthesis rates of all components of the translation machinery examined in these experiments. On the other hand, kirromycin inhibition increased the differential synthesis rates of some translation components and decreased the differential synthesis rates of others. These results suggest that the metabolic regulation of synthesis of various translation proteins is not mediated through a common signal.     

Catechol and phenol degradation by a methanogenic population of bacteria

An anaerobic population of bacteria became acclimated to catechol and phenol in 32 and 18 days, respectively. Evidence from carbon balance measurements indicates that the aromatic ring is cleaved and that the products are stoichiometrically fermentable to methane and carbon dioxide.     

Measurement of prostaglandin F2α levels in cerebrospinal fluid of febrile and afebrile patients with advanced cancer

Prostaglandin F_2α levels were measured by radioimmunoassay in 95 samples of unextracted human cerebrospinal fluid obtained from 73 patients with advanced cancer. Concentrations okf PGE were too low to be reliably determined by this method using the commercially available kits. Forty-six of the samples assayed contained <25pg/ml PGF_2α. The remaining levels ranged from 25 to 1154 pg/ml c.s.f.; the majority contained less than 200pg/ml. A possible correlation was found between elevated c.s.f. granulocyte count and increased PGF_2α. A similar relationship was found with regard to protein. These studies failed to demonstrate a correlation between elevated levels of PGF_2α in cerebrospinal fluid and any pathophysiologic condition.     

Binding of mercury(II) to poly(dA-dT) studied by proton nuclear magnetic resonance

The binding of Hg(II) to poly(dA-dT) has been examined with proton NMR spectroscopy. Addition of HgCl2 between r (Hg2+/nucleotide) = 0 and 0.25 results in loss of the exchangeable imino N3H resonance of thymine, indicating preferential binding at this site. The nonexchangeable base resonances AH8, AH2, and TH6 shift their intensity downfield in a cooperative manner, indicating complexation which is slow on the NMR time scale and changes in the polymer conformation upon binding. At r = 0.25, the polymer is cross-linked, and an increase in temperature does not result in denaturation of the polymer, as evidenced by the thymine proton resonance chemical shifts. The chemical shifts of the AH2 and T(CH3)5 base resonances allow some general conclusions to be made about the stereochemistry of this complex.     

The organization of the gene for the human cerebroside sulfate activator protein

The organization of 14 exons covering 97% of the cDNA sequence of human cerebroside sulfate activator protein precursor has been determined from two overlapping EMBL-4 human genomic clones extending over 17kb. All exons and exon/intron splice junctions and five introns were sequenced. Exon 8 consists of only 9 bp and is involved in alternative splicing which generates three different mRNAs of cerebroside sulfate activator precursor.     

Molecules,fossils, and the origin of tetrapods

Summary Since the discovery of the coelacanth, Latimeria chalumnae, more than 50 years ago, paleontologists and comparative morphologists have debated whether coelacanths or lungfishes, two groups of lobe-finned fishes, are the closest living relatives of land vertebrates (Tetrapoda). Previously, Meyer and Wilson (1990) determined partial DNA sequences from two conservative mitochondrial genes and found support for a close relationship of lungfishes to tetrapods. We present additional DNA sequences from the 12S rRNA mitochondria gene for three species of the two lineages of lungfishes that were not represented in the first study: Protopterus annectens and Protopterus aethiopicus from Africa and Neoceratodus forsteri (kindly provided by B. Hedges and L. Maxson) from Australia. This extended data set tends to group the two lepidosirenid lungfish lineages (Lepidosiren and Protopterus) with Neoceratodus as their sister group. All lungfishes seem to be more closely related to tetrapods than the coelacanth is. This result appears to rule out the possibility that the coelacanth lineage gave rise to land vertebrates. The common ancestor of lungfishes and tetrapods might have possessed multiple morphological traits that are shared by lungfishes and tetrapods [Meyer and Wilson (1990) listed 14 such traits]. Those traits that seem to link Latimeria and tetrapods are arguably due to convergent evolution or reversals and not to common descent. In this way, the molecular tree facilitates an evolutionary interpretation of the morphological differences among the living forms. We recommended that the extinct groups of lobe-finned fishes be placed onto the molecular tree that has lungfishes and not the coelacanth more closely related to tetrapods. The placement of fossils would help to further interpret the sequence of morphological events and innovations associated with the origin of tetrapods but appears to be problematic because the quality of fossils is not always high enough, and differences among paleontologists in the interpretation of the fossils have stood in the way of a consensus opinion for the branching order among lobefinned fishes. Marshall and Schultze (1992) criticized the morphological analysis presented by Meyer and Wilson (1990) and suggest that 13 of the 14 morphological traits that support the sister group relationship of lungfishes and tetrapods are not shared derived characters. Here we present further alternative viewpoints to the ones of Marshall and Schultze (1992) from the paleontological literature. We argue that all available information (paleontological, neontological, and molecular data) and rigorous cladistic methodology should be used when relating fossils and extant taxa in a phylogenetic framework. Offprint requests to: Axel Meyer