Chitosan: evaluation of a new hemostatic agent

Topically applied chitosan fails to improve the control of bleeding in a liver laceration model when compared to pressure alone in both normal and heparinized rats, and both chitosan and pressure alone are significantly less effective in controlling bleeding than the application of thrombin. In addition, our histologic results suggest that there may be an increased inflammatory response by the healing liver following topical application of chitosan.     

Immunohistochemical localization of fibronectin in the chinchilla cochlea

The purpose of this study was to better understand the molecular composition of the cochlea. Fibronectin (FN), a well characterized adhesive glycoprotein, was localized by immunofluorescence microscopy in fresh and fixed cochlear tissues, and in fixed kidney tissue, using a polyclonal, affinity-purified, rabbit, anti-fibronectin antibody and a secondary antibody coupled to FITC. The FN antibody was free from cross-reactivity with other known basement membrane and cell matrix molecules. FN reactivity in the cochlea was most intense in the basilar membrane, latero-basal borders of Boettcher's cells, otic capsule, endothelial basement membranes (particularly those of the stria vascularis), and as a diffuse, fan-shaped network radiating into the spiral ligament. Little FN labelling was present in the epithelial basement membranes. Negative control tissue showed no immunoreactivity; whereas, positive kidney control tissue showed appropriate FN immunoreactivity in the mesangium of the glomerulus. The most significant finding of this study was that FN is a major component of the basilar membrane and its distribution appears to correspond to the amorphous ground substance. FN was not localized in the organ of Corti or at the tips of the hair-cell stereocilia.     

Experimental verification of a model describing the occupied volume by polymers in solution

A relation is proposed which yields the occupied volume by macromolecular chains in solution. The experimental verification of the model is carried out by a viscometric study of the ternary system polymer A/polymer B/solvent. More precisely the viscometric study permits the determination of the critical concentration c^** corresponding to the incipient overlap of spherical coils.     

Interleukin-4 downregulates interleukin-6 production in human peripheral blood mononuclear cells

We report that recombinant human interleukin-4 (IL-4) downregulates interleukin-6 (IL-6) production by human peripheral blood mononuclear cells (PBMC). PBMC were preincubated for up to 24 hr in the presence of IL-4 (100 U/ml) and then activated with lipopolysaccharide B Escherichia coli 026:B6 (LPS, 10 micrograms/ml), recombinant human tumor necrosis factor-alpha (TNF-alpha, 200 U/ml), or Concanavalin A (Con A, 10 micrograms/ml). Although all these signals induced IL-6 production, IL-4-treated cells produced significantly reduced levels of IL-6 protein. This effect was dose and time dependent. We conclude that IL-4 is a potent downregulatory modulator of IL-6 expression in human PBMC.     

Mitochondrial DNA mutation and heteroplasmy in type I Leber hereditary optic neuropathy.

Leber hereditary optic neuropathy (LHON) is a maternally inherited disorder characterized by bilateral acute or subacute loss of central vision, primarily in young males. A G----A single base mutation at 11778nt of the mitochondrial genome which eliminates a SfaNI restriction site [Wallace et al., 1988; Holt et al., 1989; Hotta et al., 1989; Singh et al., 1989; Vilkki et al., 1989; Yoneda et al., 1989; Stone et al., 1990; Lott et al., 1990.] has been found in more than 60% of the families with LHON studied. We studied 25 persons from 4 families with LHON using SfaNI and Mae III digestion of a 201 base pair polymerase chain reaction (PCR) product encompassing the 11778nt mutation. The loss of the SfaNI site and the acquisition of a Mae III site at 11778nt were identified in all maternal relatives of the LHON families studied. The mutation was heteroplasmic in all affected individuals, female carriers, and males at-risk. The heteroplasmy of mitochondrial DNA (mtDNA) was also identified by direct DNA sequencing of PCR amplified by direct DNA sequencing of PCR amplified mtDNA digested by SfaNI or Mae III. It appears that the proportion of the mutant mtDNA correlates with the severity of the disease.     

Homozygosity mapping of achromatopsia to chromosome 2 using DNA pooling

Achromatopsia is an autosomal recessive disease of the retina, characterized clinically by an inability to distinguish colors, impaired visual acuity, nystagmus and photophobia. A genome-wide search for linkage was performed using an inbred Jewish kindred from Iran. To facilitate the genome-wide search, we utilized a DNA pooling strategy which takes advantage of the likelihood that the disease in this inbred kindred is inherited by all affected individuals from a common founder. Equal molar amounts of DNA from all affected individuals were pooled and used as the PCR template for short tandem repeat polymorphic markers (STRPs). Pooled DNA from unaffected members of the kindred was used as a control. A reduction in the number of alleles in the affected versus control pool was observed at several loci. Upon genotyping of individual family members, significant linkage was established between the disease phenotype and markers localized on chromosome 2. The highest LOD score observed was 5.4 (theta = 0). When four additional small unrelated families were genotyped, the combined peak LOD score was 8.2. Analysis of recombinant chromosomes revealed that the disease gene lies within a 30 cM interval which spans the centromere. Additional fine-mapping studies identified a region of homozygosity in all affected individuals, narrowing the region to 14 cM. A candidate gene for achromatopsia was excluded from this disease interval by radiation hybrid mapping. Linkage of achromatopsia to chromosome 2 is an essential first step in the identification of the disease-causing gene.      

Mitochondrial genetics of Coprinus: Recombination of mitochondrial genomes

Summary The formation of the sexual mycelium or dikaryon in the basidiomycete Coprinus cinereus involves exchange and migration of nuclei without accompanying exchange of mitochondria. The dikaryotic growth which appears around the periphery of mated monokaryons has exclusively the mitochondrial genome of the recipient cells. Recombination of mitochondrial genomes is not, however, precluded during dikaryosis. Using monokaryons with different mitochondrial gene mutations, [acu-10] causing cytochrome aa ₃ deficiency and[cap-1.1] conferring resistance to chloramphenicol, it was shown that recombinant mitochondria arise in the zone of contact of mated monokaryons.     

Milk of calcium syndrome: a diagnosis to be made before the scheduling of lithotripsy. Consideration apropos of 6 cases

The authors report six cases of milk of calcium syndrome. As in previously published cases, the diagnosis was established by the film taken in the standing position: the "lithiasic density" shrinks, densifies and exhibits a horizontal upper edge. Four patients were at first mistakenly diagnosed as having urinary lithiasis for which extracorporeal lithotripsy was scheduled. In one case, the lithotripsy was actually performed and the diagnosis of milk of calcium disease was established only immediately after the procedure. In another patient, lithotripsy was performed because small stones were thought to be present in the milk of calcium. In the two other cases, the diagnosis was made on the day before scheduled lithotripsy and this procedure was therefore cancelled. The purpose of the authors in reporting these cases is above all to point out the diagnostic value of a plain film of the abdomen in the standing position. Diagnosis must be made in time to avoid extracorporeal lithotripsy since, in milk of calcium syndrome, this procedure is illogical, inefficient and probably more hazardous than useful. On the basis of the six cases reported herein and of data from the literature, several characteristics of milk of calcium syndrome can be emphasized. Milk of calcium syndrome predominantly affects individuals with a positive personal or family history for renal lithiasis. It occurs in both sexes and all age groups, including childhood. Milk of calcium syndrome complicates partial or total dilatation of the urinary tract. Crystallization may be of the phosphatic or oxalic type. Concomitant urinary tract infection is common.(ABSTRACT TRUNCATED AT 250 WORDS)     

Provisional "normograms" for identifying adenocarcinomas of the prostate or colon and hepatocellular carcinoma derived from their distribution of proteins separated by two-dimensional electrophoresis

The distribution of proteins in samples from 8 prostate and 4 colon adenocarcinomas and 1 hepatoma was analyzed by 2-dimensional protein electrophoresis. Composite "normograms" based upon their distribution of proteins were developed from these patterns. Particular attention was paid to acidic proteins between pI 3.5 and 5.9. Of 161 proteins enumerated, 23 of the first 135 were present in prostate cancers, compared with 68 in colon cancer and 85 in the hepatoma. The 26 proteins denoted from nos. 135 to 161 were prostate associated, and none was evident in the colon or hepatoma samples. Twenty-seven prostate, 20 colon, and 48 liver cancer proteins were "unique" to each of the 3 cancers, respectively. The patterns of protein associated with each type of cancer were so dissimilar that with this technique no difficulty should be experienced in distinguishing these carcinomas originating from 3 different types of "stem" cells without obligatory recourse to microscopy.     

Expressed emotion in families of chronic schizophrenics and its association with clinical measures

Summary A controlled clinical study on the outcome of family intervention in chronic schizophrenics is being carried out in Athens. All subjects participating in the study reside with their families and attend a vocational rehabilitation unit. Those belonging to families characterized by high Expressed Emotion (EE) are randomly assigned to either the experimental or the control condition. The former receive family intervention combined with individual treatment, the latter individual treatment alone. 75 subjects have entered the study, and 121 relatives were interviewed with the Camberwell Family Interview. 40 patients (53.3%) were found to belong to high EE families. The present article presents the results of the baseline assessment. It was found that the EE status of the family was significantly associated with measures of psychopathology and social functioning (BPRS, GAS, DAS, number of residual symptoms). Further analyses revealed that these associations exist only when all key relatives express high EE. The implications of these findings are discussed.An earlier draft of this article was presented at the VIII World Congress of Psychiatry