Cloning, expression and characterization of a murine-human chimeric antibody with specificity for pre-S2 surface antigen of hepatitis B virus

The cloning, expression and characterization of a murine-human chimeric antibody with specificity for the pre-S2 surface antigen (Ag) of hepatitis B virus (HBV) is described. The heavy and light chain variable region (VH and VL) genes encoding the murine monoclonal antibody (mAb) were isolated and combined with human γ 1 and κ constant region genes, respectively. The expression vectors containing the chimeric heavy and light chain genes were sequentially electroporated into murine Sp2/0 hybridoma cells and transfectomas secreting chimeric antibody were isolated. The chimeric antibody was purified and characterized by ELISA, Western analysis and competition immunoassay, demonstrating that the transfectoma functionally express and secrete murine-human chimeric antibody which retained the specificity and affinity of the parental murine mAb.     

Bizarre leiomyoma of the scrotum

Scrotal leiomyomas with atypical bizarre nuclei are rare, which might be misdiagnosed as malignant tumor. We describe a case of scrotal bizarre leiomyoma in a 65-yr-old man. The tumor was a 1 cm-sized, well circumscribed, oval mass arising from the tunica dartos muscle. Histologically, it was formed by whorling bundles of fusiform cells with occasional atypical, pleomorphic nuclei and pseudo-inclusions. Mitosis was not found. Although morphologically atypical, scrotal bizarre leiomyomas take on a biologic behavior not different from that of conventional leiomyoma, they should be distinguished from leiomyosarcoma to avoid unnecessary treatment.     

Chromosome breakage, fusion and reconstruction during P1dl transduction

A P1dl lysogen with some capacity for virion production, PL0100 Δ111 (P1dl), has been produced through low-frequency transduction of lac⁺ genes from wild type Escherichia coli to a recipient with the proA-lac deletion X111 (Δ111). The P1dl is a plasmid but has some homology with the host chromosome next to the Δ111 locus. When transduction is accomplished by single virions from PL0100, transductants with genetically novel P1dl derivatives are obtained. Most common are transductants with P1dl unstably integrated next to Δ111. There are also transductants phenotypically comparable to PL0100, but distinguishable from PL0100 by the properties of virions they produce. It is shown for a minute-plaque-forming derivative of the P1dl, P1min, that the genetically novel elements arise as a consequence of the transduction processes. Transductants indistinguishable from PL0100(P1dl are obtained when two P1dl containing virions and temperate P1 coinfect Δ111 recipients.It is suggested that the P1dl chromosome is too large to be wholly encapsidated in P1 virions; novel P1dl derivatives are formed when transduced P1dl fragments are circularized through a fusion of DNA ends in recipients; in recipients of genetically complementary P1dl DNAs, P1dl chromosome reconstruction sometimes proceeds through crossing-over. Applications of these findings to problems of P1dl formation through low-frequency transduction are discussed.     

Sodium channels in ocular epithelia

Voltage-gated, tetrodotoxin(TTX)-blockable sodium channels are found in most excitable cells and are the primary contributors to action potentials generated by many of these cells. To date, there has only been one report of a non-cultured vertebrate epithelial cell type containing TTX-blockable Na⁺ channels: rabbit non-pigmented ciliary body epithelial cells [Cilluffo MC et al. (1991) Invest Opthalmol Vis Sci 32:1619–1629], and three reports of cultured epithelial cells containing TTX-blockable Na⁺ channels: rabbit non-pigmented and pigmented ciliary body epithelium [Ciluffo MC et al. (1991) Invest Opthalmol Vis Sci 32:1619–1629; Fain GL, Farahbakhsh (1989) J Physiol (Lond) 417:83–103] and human lens epithelium [Cooper K et al. (1990) J Membr Biol 117:285–298]. We report here the presence of sodium currents in two different non-cultured, freshly dissociated transporting epithelial cell types: the rabbit corneal endothelium and the frog lens epithelium. We also report the occurrence of sodium currents in six additional cultured ocular epithelial cell types from three different species. These currents have a current/voltage (I/V) relationship consistent with traditional voltage-gated Na⁺ currents, are quinidine- and TTX-blockable (of the low-affinity TTX-sensitive type), and disappear following bath substitution of Na⁺ with Cs⁺ or K⁺.     

Identification of two mutations in a compound heterozygous child with dihydrolipoamide dehydrogenase deficiency

An infant girl with elevated blood lactate, pyruvate, and plasma branched-chain amino acids was diagnosed with dihydrolipoamide dehydrogenase (E3; dihydrolipoamide: NAD+ oxidoreductase, EC 1.8.1.4) deficiency. Activities of the pyruvate dehydrogenase complex and E3 from patient were 26 and 2% of controls in blood lymphocytes, and 11 and 14% in cultured skin fibroblasts, respectively. Western blot analysis demonstrated that the amount of E3 protein in fibroblasts from the patient and her father was about half of controls, while Northern blot analysis showed normal amounts of E3 RNA. DNA sequencing of cloned full-length E3 cDNAs from the patient revealed two mutations in separate alleles. One is a single base insertion of an extra adenine in the last codon of the leader peptide sequence (TAC-->TAAC) leading to a nonsense mutation which results in the premature termination of the precursor E3 polypeptide (Y35X). The other is a missense mutation due to substitution of guanine for adenine, causing an Arg-->Gly substitution at amino acid 460 of the mature protein (R460G) which triggers the loss of E3 activity probably by structural change in the E3 dimer. DNA sequencing of E3 cDNAs from the parents demonstrated that the nonsense mutation was inherited from the father and the missense mutation was inherited from the mother.      

Exclusion criteria of DSM-III. A study of co-occurrence of hierarchy-free syndromes

The diagnostic criteria of the third edition of the DSM-III often state that one diagnosis cannot be made if it is "due to" another disorder. Using data from the National Institute of Mental Health Diagnostic Interview Schedule, with a sample of 11,519 subjects from a community population, we found that if two disorders were related to each other according to the DSM-III exclusion criteria, then the presence of a dominant disorder greatly increased the odds of having the excluded disorder. We also found that disorders, which DSM-III says are related to each other, were more strongly associated than disorders, which DSM-III says are unrelated. However, we also found there was a general tendency toward co-occurrence, so that the presence of any disorder increased the odds of having almost any other disorder, even if DSM-III does not list it as a related disorder. We concluded that empirical studies are needed to study the assumptions underlying the use of a diagnostic hierarchy.     

Helicobacter pylori-induced diarrhea post-ileogastrostomy

A retrospective study of all ileogastrostomy procedures (n=26) performed in 1993 by one surgeon (IGMC) was carried out to investigate the hypothesis that Helicobacter pylori may be implicated in certain severe cases of postoperation nausea and diarrhea. Ten of 26 persons (38.5%) displayed nausea and notable diarrhea (greater than or equal to ten bowel movements per day), seven of which warranted upper GI investigation. One hundred per cent (seven of seven) of these persons were found to possess H. pylori upon C-14 breath test. In four of six cases eradication therapy (1 g amoxicillin b.i.d./20 mg omeprazole b.i.d. for 2 weeks) corresponded with a resolution of severe nausea and diarrhea (one additional case involved omeprazole use only), suggesting that H. pylori should be considered as a possible cause of these symptoms post-ileogastrostomy. Additionally, in four of seven cases persons were re-tested (C-14 breath analysis) at least 1 month post-therapy and in this group three persons were found to be free of the organism. All three cases of notable diarrhea and nausea resolved with treatment, providing the strongest evidence for a possible association between infection and these symptoms.     

The association between frequency of diagnostic radiological examinations and allocation of resources in the National Health Service: implications for future demand

A highly significant association is noted between the frequency of diagnostic radiological examinations and the relative level of funding in the English Regional Health Authorities as calculated by the Resource Allocation Working Party in 1977 (DHSS, 1976). It is argued that this supports the recommendations of the Resource Allocation Working Party, and their suggestion that Standardized Mortality Ratios can be used as a proxy measure for morbidity. The finding implies that the level of diagnostic radiology is likely to rise if more funds become available, and this conclusion is supported by consideration of the level of diagnostic radiology in other industrialized countries. The correlation with level of funding is also investigated for a number of other indicators of hospital use. Strong associations exist for some usage indicators for out-patients, but not for in-patients.