Studies on the development of diluents for the transportation and storage of human semen at ambient temperature

Storage of human semen samples at ambient temperature for 24 h resulted in a significant loss of sperm motility from a mean 45.1 +/- 1.8% to 13.8 +/- 1.1% (n = 148). This motility loss was associated with a significant increase in the osmolality of the seminal plasma and the induction of peroxidative damage to the spermatozoa. Both of these detrimental changes could be prevented by diluting the original semen sample 1:1 with a citrate-egg yolk, buffer (CYB). In the presence of this extender all aspects of semen quality were efficiently preserved for 24 h, including sperm movement, penetration of a cervical mucus substitute, the acrosome reaction and sperm-oocyte fusion. CYB extension also permitted the use of chemiluminescent tests of leukocyte contamination to be performed on semen samples stored for 24 h at ambient temperatures. As a preservation medium, CYB was found to be superior to alternative formulations lacking citrate and storage at ambient temperatures was preferable to 4 degrees C. Significant improvements in motility retention were also observed when CYB was supplemented with pentoxifylline, although this treatment significantly stimulated peroxidative damage in the spermatozoa. However, if the pentoxifylline was combined with antioxidants then this collateral peroxidative damage could be reduced and the performance of CYB significantly enhanced. These results have implications for the design of diluents permitting the long-term storage and transportation of human semen samples at ambient temperatures.     

The supinator notch sign in rheumatoid arthritis

Unconcentrated CSF and 200 times diluted serum samples from 192 patients were examined by agar electrophoresis; their albumin and transferrin content were determined simultaneously by radial immunodiffusion. Using the data on transferrin and albumin concentrations in serum and cerebrospinal fluid, the transferrin/albumin index was calculated in a similar way to the IgG/albumin index. Normally the transferrin/albumin index is 1.68 (n = 77; S.D. = 0.22). If the permeability of the blood-CSF barrier increases, the transferrin/albumin index gradually decreases to 1. If the tau-globulin fraction is increased on the agar pherogram, the transferrin/albumin index will be greater than 2.34 (mean + 3 S.D.).     

Phakomatous choristoma of eyelid: electron microscopical confirmation of lenticular derivation

This article presents the sixth recorded example of phakomatous choristoma of the eyelid. The tumor occurred in a 4-month-old boy and was located in the lower lid near the inner canthus. The findings from light microscopy included epithelial, tubular structures with associated patches of thick, irregular basement membrane. The results of electron microscopy (ie, epithelial cells with a scarcity of organelles, homogeneous type of basement membrane, cytoplasmic microfilaments, segments of fascia occludens, and degenerated cells with peculiar interdigitations of their plasmalemmas) are all consistent with lenticular derivation, as originally proposed by Zimmerman.     

Nuclear localization of the interferon-inducible protein kinase PKR in human cells and transfected mouse cells

The levels and subcellular distribution of the interferon-inducible double-stranded RNA-dependent protein kinase PKR have been measured in human Daudi cells and stably transfected mouse NIH 3T3 cells expressing the human protein kinase. Immunofluorescence of intact cells and quantitative immunoblotting of cell extracts indicate that PKR occurs in both the cytoplasm and the cell nucleus, with staining specifically in the nucleolus. The ratio of cytoplasmic to nuclear PKR is approximately 5:1 in control cells; in response to interferon treatment the protein kinase is induced severalfold in the cytoplasm whereas the level in the nucleus does not increase significantly. Analysis of individual transfected cells by confocal microscopy reveals a pattern of distribution of PKR similar to that in Daudi cells, with immunostaining of cytoplasm and nucleoli. Similar results are observed whether cells expressing wild-type PKR or a catalytically inactive mutant form of the kinase are analyzed, but untransfected 3T3 cells are not stained by the antibody used. Two-dimensional isoelectric focusing analysis of PKR in whole cell extracts reveals the presence of multiple forms with different pI values whereas similar analysis of the nuclear fraction indicates only one predominant species with a relatively basic pI. These results suggest that PKR may have a role in the cell nucleus as well as the cytoplasm and that the subcellular distribution of the protein kinase may be related to post-translational modifications.     

Distribution of genes conferring combined resistance to tetracycline and minocycline among group B streptococcal isolates from humans and various animals

Forty-nine tetracycline and minocycline resistant streptococci of serological group B isolated from humans, cattle, pigs and nutrias were investigated for the presence of genes conferring this combined resistance. Southern blot hybridization of EcoRI-digested chromosomal DNA of the bacteria revealed for 39 of the cultures a hybridization signal with tet(M), for four of the cultures a hybridization signal with tet(O) and for none of the cultures a hybridization signal with the tet(Q) gene probe. The restriction endonuclease digested and blotted DNA of six tetracycline and minocycline resistant group B streptococci did not hybridize with any of the available gene probes. The tet(M) gene probes recognized complementary sequences of EcoRI fragments of approximately 10.5 kb and 21.5 kb, the tet(O) gene probe hybridized with fragments of approximately 19 kb. The hybridization of the tet(M) gene probe in two different patterns appeared to be related to the origin of the cultures.     

Exclusion of atrial thrombus by transesophageal echocardiography does not preclude embolism after cardioversion of atrial fibrillation. A multicenter study

BACKGROUND: Transesophageal echocardiography (TEE) has been used recently to detect atrial thrombi before cardioversion of atrial arrhythmias. It has been assumed that embolic events after cardioversion result from embolism of preexisting atrial thrombi that are accurately detected by TEE. This study examined the clinical and echocardiographic findings in patients with embolism after cardioversion of atrial fibrillation despite exclusion of atrial thrombi by TEE. METHODS AND RESULTS: Clinical and echocardiographic data in 17 patients with embolic events after TEE-guided electrical (n = 16) or pharmacological (n = 1) cardioversion were analyzed. All 17 patients had nonvalvular atrial fibrillation, including four patients with lone atrial fibrillation. TEE before cardioversion showed left atrial spontaneous echo contrast in five patients and did not show atrial thrombus in any patient. Cardioversion resulted in return to sinus rhythm without immediate complication in all patients. Thirteen patients had cerebral embolic events and four patients had peripheral embolism occurring 2 hours to 7 days after cardioversion. None of the patients were therapeutically anticoagulated at the time of embolism. New or increased left atrial spontaneous echo contrast was detected in four of the five patients undergoing repeat TEE after cardioversion including one patient with a new left atrial appendage thrombus. CONCLUSIONS: Embolism may occur after cardioversion of atrial fibrillation in inadequately anticoagulated patients despite apparent exclusion of preexisting atrial thrombus by TEE. These findings suggest de novo atrial thrombosis after cardioversion or imperfect sensitivity of TEE for atrial thrombi and suggest that screening by TEE does not obviate the requirement for anticoagulant therapy at the time of and after cardioversion. A randomized clinical trial is needed to compare conventional anticoagulant management with a TEE-guided strategy including anticoagulation after cardioversion.