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Biomedical subjects

D Kiefer

Publications and source records attributed to D Kiefer.

34 records · Page 2Linked to original sources

Two previously undescribed extracellular streptococcal antigens detectable with naturally occurring human antibodies.

Two streptococcal extracellular antigens (X and Y), which are detectable with naturally occurring human antibodies, have been isolated and shown to represent entities distinct from previously described streptococcal enzymes, toxins, and antigens. They are each synthesized by both group C and group A streptococci and appear to be proteins. Both antigens were found to be nonhemolytic and nontoxic for human leucocytes as well as for isolated beating newborn rat heart cells in tissue culture. In addition to being distinct from known streptococcal enzymes, they were also shown to be devoid of several other enzymatic activities.

Animals↗

Quantitative analysis of pregnancy-associated plasma proteins in human placenta.

By immunochemical methods and simultaneous measurements of several normal plasma proteins, human placenta was shown to contain elevated quantities of four pregnancy-associated plasma proteins (PAPP's). In the order of increasing amounts, PAPP-A, PAPP-C, PAPP-B, and human chorionic somatomammotropin (PAPP-D) all were present in placenta extracts in quantities greater than could be expected on the basis of their content in maternal blood. In sharp contrast, the placental content of pregnancy zone protein could be entirely accounted for by the maternal plasma present in the placenta. All of the PAPP's appeared to be readily extractible from placental tissue with buffered saline, the large bulk of them being solubilized in the first extraction procedure. However, absorption studies indicated that appreciable quantities of the PAPP's were still present in the insoluble placental residue after 12 sequential extractions with saline. The chorioamniotic membranes were not significantly enriched in any of the PAPP's. Immunochemical analysis of unwashed placental tissue extracts for the PAPP's IgA, and IgM (maternal blood derived), as well as albumin and transferrin (maternal and fetal blood derived), permitted calculations to be made of the amount of blood and PAPP's in placenta. On the basis of these data, it was roughly estimated that a 400-g placenta (wet weight) would occupy 312 ml in volume, and would contain 144 ml of blood. Of this blood, 36 ml would be derived from the mother.

Antibodies↗

Two pancreas "tissue-specific" antigens in normal human urine, one being and esterase.

Hyperimmune antiserum to human pancreas was exhaustively absorbed with plasma, kidney, and submaxillary gland. The resulting antiserum showed up to seven antigens in pancreas extracts by gel diffusion methods, but failed to react detectably with extracts of 17 other organs and tissues. However, this apparently "tissue-specific" anti-pancreas reagent regularly revealed two of the pancreas antigens in normal human urine concentrates. One of the latter was an anodal esterase. Although the identity of the second is not yet known, it was shown to be devoid of the following enzyme activities: amylase, catalase, glucosaminidase, glucuronidase, cystine-aminopeptidase, phosphatases and sulfatase.

Absorption↗

A review of 12 commonly used medicinal herbs.

A large and increasing number of patients use medicinal herbs or seek the advice of their physician regarding their use. More than one third of Americans use herbs for health purposes, yet patients (and physicians) often lack accurate information about the safety and efficacy of herbal remedies. Burgeoning interest in medicinal herbs has increased scientific scrutiny of their therapeutic potential and safety, thereby providing physicians with data to help patients make wise decisions about their use. This article provides a review of the data on 12 of the most commonly used herbs in the United States. In addition, we provide practical information and guidelines for the judicious use of medicinal herbs.

Chamomile↗

Treatment of sperm with subnormal host scores with chymotrypsin/viable pregnancy after IUI.

Men with low hypoosmotic swelling test (HOST) scores (<50%) rarely achieve a pregnancy with intercourse or conventional intrauterine insemination (IUI) or even IVF. The defect seems to be related to a toxic factor attached to the sperm that can be transferred to the zona pellucida, which ultimately interferes with implantation. A small case series showed optimistic pregnancy outcome with treatment of the sperm with low HOST scores with chymotrypsin. However, the live pregnancy rate in 90 subsequent IUI cycles in men whose low HOST scores were improved by chymotrypsin was only 3.3%. IVF with ICSI remains the only highly effective treatment of this disorder.

Chymotrypsin↗

Sperm toxicity evaluated by the overnight sperm survival test.

A subnormal sperm stress test has also been associated with implantation failure despite apparently normal fertilization; however, this test is cumbersome and time-consuming. The overnight sperm survival test has been considered to possibly demonstrate lipid peroxidation abnormalities similar to the sperm stress test. The present study evaluated whether lower overnight survival scores were associated with lower pregnancy and implantation rates following in vitro fertilization-embryo transfer. The results showed no adverse effect of poor overnight survival test scores. Possibly, the overnight survival test, though similar in some respects to the sperm stress test, is not similar for properties of predicting embryo implantation defects. Corroboration that subnormal stress tests predicts implantation disorders is needed.

Adult↗

Oligoasthenozoospermia is not associated with spontaneous abortions following in vivo pregnancies contrasting with in vitro fertilization data.

Previous data showed an association between low motile density (< 10 million motile/mL) and spontaneous abortion (SAB) following in vitro fertilization-embryo transfer (IVF-ET). The purpose of this study was to determine if the same association existed following intrauterine insemination (IUI). A retrospective review of IUI pregnancies was conducted. Patients with antisperm antibodies, a low hypo-osmotic swelling (HOS) test score (< 50%), or those using donor sperm were excluded. A total of 52 couples were enrolled in the study: 34 in the normal motile density (MD) group and 18 in the low MD group. The SAB rate in the normal group was 29.4% and in the low group was 27.8%. Thus, these data fail to corroborate the conclusions reached after evaluation of IVF pregnancies that low MD is a cause of SAB. However, since there is a large difference in the number of sperm that come in contact with the oocyte following IVF versus IUI, it may be that the implantation defect is not evident until the oocyte is exposed to a certain number of abnormal sperm.

Abortion, Spontaneous↗

Effects of Percoll discontinuous density gradients vs SpermPrep II vs Sephadex G-50 gel infiltration on semen parameters.

There are various methods of separating sperm from seminal plasma for subsequent intrauterine insemination. Some of these same techniques have been employed for female sex selection. The purpose of the present study was to assess and compare semen parameters following Sephadex, Percoll, and SpermPrepII separation techniques. The SpermPrepII is also a Sephadex preparation but uses a different bead size, less Sephadex, and is a slightly quicker method. The specimens (n = 16) were initially evaluated for count, (C; x 10(6)/mL), percent motility (MO), grade of motility (GR; percent) and hypoosmotic swelling (HOS) test scores. Each specimen was then divided into three equal aliquots and prepared as follows: (1) layered onto a modified Percoll discontinuous density gradient column; (2) processed using SpermPrepII; and (3) filtered through a Sephadex gel filtration column (G-50). The results show all three treatments yielded lower (P < 0.01) counts as compared to control values, but no differences were noted among them. Percoll SpermPrepII increased MO (P < 0.01) whereas Sephadex reduced it (P = NS). Percoll and SpermPrepII improved the percentage of better quality sperm but not Sephadex; SpermPrepII was slightly higher than Percoll, but the difference was not significant. There were increases (P < 0.05) in HOS values in all experimental treatments, with SpermPrepII having the highest scores. However, this study did not show as many males with HOS scores below 50% as noted in other studies. Percoll and SpermPrepII seem to be equally effective methods for producing high-quality sperm for intrauterine insemination or in vitro fertilization.

Cell Separation↗

Effect of pentoxifylline added to freezing media on subsequent post-thaw hypoosmotic swelling test and other semen parameters.

This study evaluated the effects of pentoxifylline (PTX) on post-thaw semen parameters as well as the hypoosmotic swelling (HOS) test. Fourteen samples were evaluated for volume, count, motility, % grade A sperm, and HOS test. Two aliquots were frozen, one in freezing medium and the other in a 3 mM solution of PTX and freezing medium. Both groups were frozen in liquid nitrogen vapors for 30 min. Thawing was performed at 37 degrees C for 15 min, followed by a wash with 2 parts 0.5% HSA/MHTF to 1 part sample. Pellets were resuspended in 0. MHTF and then evaluated as described above. In addition, motility was evaluated 2 h post-thaw. Following freeze-thaw, the mean motile densities were similar (17.5 x 10 motile/mL vs. 20.4 x 10(6) motile/mL for PTX and control, respectively). Two hours post-thaw, the PTX group had a mean sperm motility of 31.3% vs. 37.7% for the control group (p > .05). There were no significant differences in % grade A sperm in PTX (13.0%) vs. control (12.0%). Similarly, HOS scores did not improve following cryopreservation (43.0% and 50.6% for PTX and control, respectively). Thus, no improvement was found by freezing sperm with PTX.

Analysis of Variance↗

The value of motile density, strict morphology, and the hypoosmotic swelling test in in vitro fertilization-embryo transfer.

This study was conducted to evaluate the effect of a single abnormal semen parameter on subsequent implantation and pregnancy rates (PRs) following in vitro fertilization-embryo transfer (IVF-ET). The parameters evaluated were motile density (MD), strict normal morphology (SNM), and the hypoosmotic swelling (HOS) test. A total of 592 IVF cycles were evaluated. Patients were divided into four groups each with one abnormal semen parameter except for the control: group 1 (n = 509), control group: MD > or = 10 x 10(6)/mL, HOS > or = 50%, SNM > or = 4%; group 2 (n = 51): HOS and SNM normal, MD < 10 x 10(6)/mL; group 3 (n = 14): MD and SNM normal, HOS < 50%; group 4 (n = 18): MD and HOS normal, SNM < 4%. The implantation rate was 10.2% for the control group. The implantation rate was similar for the low MD (9.0%) and the low SNM (16.7%) groups. However, the low HOS group had a significantly lower implantation rate (0%). The clinical PRs are similar in the control group and low MD and SNM groups, but decreased in the low HOS group (21.5, 15.0, 30.8, and 0%, respectively). Ongoing PRs were also similar with the exception of the low HOS group (0%). This comparative study supports previous conclusions that the subnormal HOS test is the best semen parameter available that predicts poor PRs. It also suggests that some qualitative defect in the embryos may result from defective sperm membranes, resulting in an apparently normal appearance but physiologically defective embryo.

Cell Count↗

Finding information on herbal therapy: a guide to useful sources for clinicians.

Many resources are available to patients and healthcare practitioners interested in learning about complementary and alternative medicine (CAM) therapies such as herbal medicine. This article provides a comprehensive review of herbal medicine sources that are general in scope, clinically oriented, evidence based, and focused on Western phytomedicinals. Tables list 15 books and 8 Internet sites that fulfill these criteria. Information also is provided on 4 monographs, literature databases, and many related sources that may be of interest to clinicians incorporating herbal medicines into their practice or counseling patients on the topic.

Books↗