PubMed Health⌕ Search

Biomedical subjects

M Seibel

Publications and source records attributed to M Seibel.

36 records · Page 2Linked to original sources

Why patients fail antibiotic prophylaxis at cesarean delivery: histologic evidence for incipient infection.

A prospective, blinded study was conducted to test the hypothesis that antimicrobial prophylaxis failure after cesarean delivery is associated with incipient infection of the uterus, as determined by histologic evaluation of bacterial invasion and acute inflammatory cell response. One hundred nineteen patients undergoing cesarean delivery and receiving antibiotic prophylaxis were included in this study. At the time of the operation, a hysterotomy biopsy was obtained for hematoxylin and eosin staining. Marked histologic differences were noted in decidual inflammation, myometrial inflammation, and myometrial polymorphonuclear cell invasion in those patients who subsequently developed endometritis (N = 7) compared with subjects without postpartum endometritis. Using two techniques for in situ identification of bacteria within myometrial tissue (acridine orange and fluorescein DNA probe to bacterial ribosomal RNA), all clinically infected parturients demonstrated large numbers of organisms in the myometrial layer of the biopsy specimen, compared with few organisms seen in a matched subset of noninfected controls. These data support the concept that incipient infection at the time of cesarean delivery may limit the effectiveness of antimicrobial prophylaxis. Use of rapid-diagnosis methodologies may allow timely identification of these at-risk patients so that therapeutic antibiotics can be initiated.

Anti-Bacterial Agents↗

Comparison of two enzyme-linked immunosorbent assays for detection of herpes simplex virus antigen.

Two enzyme-linked immunosorbent assays (ELISAs) for herpes simplex virus (HSV) detection were compared with culture in a prospective, blinded study with 153 patients with suspected recurrent oral or genital HSV. A subset of 15 of these subjects were studied daily until symptom resolution during a single episode of recurrent HSV. Direct-site specimens were collected and either placed in viral transport media (for Ortho ELISA and fresh inoculation into primary rabbit kidney cells) or frozen in ELISA collection media (DuPont). One hundred eighty-six culture-ELISA comparisons were analyzed. On the basis of culture positivity, the DuPont and Ortho ELISAs differed substantially with regard to sensitivity (93 versus 35%) but had similar specificities (95 versus 100%) and positive (85 versus 100%) and negative (98 versus 85%) predictive values. There were seven DuPont ELISA-positive, culture-negative samples which were confirmed positive for HSV by blocking antibody test (revised specificity, 100%; positive predictive value, 100%). Six of these discrepant samples were from previously culture-positive subjects. These results demonstrate that currently available ELISA kits vary substantially as to their sensitivities in detecting HSV antigen from direct-site specimens. In addition, antigen detection, by ELISA technology, is not always synonymous with state of viral infectivity as judged by tissue culture cytopathic effect.

Antigens, Viral↗

Comparison of the in vitro fertilization rate by human sperm capacitated by multiple-tube swim-up and Percoll gradient centrifugation.

Two sperm preparation methods, a multiple-tube swim-up and Percoll-gradient centrifugation, were employed in our human in vitro fertilization program. The fertilization rate of these two sperm preparation methods was compared when they were employed in semen samples of less than 60 million motile sperm/ml. The results described here suggest that both of these methods gave a similar fertilization rate in these semen samples, i.e., 72 +/- 8% for the Percoll-gradient centrifugation method and 66 +/- 8% for the multiple-tube swim-up method.

Centrifugation, Density Gradient↗

In vitro fertilization: sonographic perspective.

The applications of sonography were evaluated in 220 patients undergoing 354 in vitro fertilization cycles. A baseline sonogram demonstrated adnexal abnormalities in 10.7% of cycles. Serial sonograms were beneficial in monitoring follicular development. Oocyte harvest was canceled in 18.4% of cycles owing to inadequate follicle growth progression, as demonstrated by ultrasound. An additional 9% of cycles were canceled owing to the development of a single lead follicle. Six percent of cycles were accompanied by a spontaneous rise in serum luteinizing hormone values, necessitating sonographic correlation to exclude ovulation.

Female↗

Characterization of insulin-like growth factor binding to human granulosa cells obtained during in vitro fertilization.

Insulin and IGF-I affect in vitro ovarian stromal and follicular cell function in several species. We previously characterized insulin receptors on human granulosa cells obtained from in vitro fertilization procedures but were unable to demonstrate specific binding of IGF-I. Following modification of the assay conditions, we now report specific, high affinity IGF-1 binding sites on human granulosa cells. Substitution of equimolar concentrations of sucrose for sodium chloride in the buffer solution increased binding of IGF but not insulin in equilibrium assays. Maximal specific IGF-I binding was 2.69 +/- 0.30%/10(5) cells (SEM, n = 9) with half-maximal inhibition of binding at 2 ng/ml IGF-I. Unlabeled insulin recognized the type I IGF receptor with low affinity. An IGF-I receptor monoclonal antibody (alpha IR-3) inhibited 125I-IGF-I but not 125I-insulin binding. Affinity crosslinking followed by SDS/PAGE under reducing conditions revealed IGF-I binding at a molecular weight compatible with the alpha subunit of the type I IGF receptor and with a pattern of inhibition by various ligands that paralleled the equilibrium binding assays. IGF-I receptors are present on freshly isolated human ovarian granulosa cells obtained following pharmacologic stimulation with gonadotrophin according to the protocols of in vitro fertilization. The biologic function of these receptors currently is being investigated.

Affinity Labels↗

An increase in in vitro fertilization ability of low-density human sperm capacitated by multiple-tube swim-up.

Comparison was made of the efficacy of multiple-tube swim-up (MT-SU) and single-tube swim-up (ST-SU) preparations on inducing human sperm fertilization ability in semen samples of less than 60 million motile sperm/ml. Two parallel groups of in vitro fertilization (IVF) patients possessing sperm density of this category had their sperm capacitated by MT-SU or ST-SU. The MT-SU patients' sperm fertilized 71 +/- 6.0% of eggs retrieved in comparison to 39 +/- 7.9% in the parallel ST-SU patients (P less than 0.001). Similarly, MT-SU increased the rate of human sperm penetration into zona-free hamster eggs. The increased fertilization rate of MT-SU sperm was not from acceleration of the acrosome reaction, but may be attributed to the higher efficiency of MT-SU in removing antifertility factors present in the seminal plasma from sperm.

Acrosome↗

Luteal phase serum progesterone levels after follicle aspiration with and without clomiphene citrate treatment.

Peripheral serum progesterone (P) levels were studied on random days after the spontaneous luteinizing hormone (LH) surge in women who underwent follicle aspiration. Comparisons were made with ovulatory women treated with clomiphene citrate (CC) undergoing follicle aspiration and women undergoing midcycle general anesthesia and laparoscopy without follicle aspiration. There were no differences in mean P levels in the group of women who underwent follicle aspiration, compared with the group who did not. Women treated with CC showed higher P levels during the first week of the luteal phase. During the second week of the luteal phase P levels were similar, regardless of follicle aspiration alone or in combination with CC use. In the groups not using CC, more individual women had P levels less than 10 ng/ml. Follicle aspiration does not appear to reduce luteal phase P levels in groups of patients in the natural menstrual cycle or receiving CC. Some individual patients, however, appear to be at risk for lower P levels, particularly after follicle aspiration or general anesthesia, in the natural cycle.

Clomiphene↗

Distribution and characterization of insulin and insulin-like growth factor I receptors in normal human ovary.

Insulin-resistant hyperinsulinemic states are now widely known to be associated with ovarian hyperandrogenism, and this is thought to be due to an action of insulin on the ovary. However, the identity of the receptor that is responsible for insulin action in these patients, whose insulin receptors on classical target tissues are severely impaired, is unclear. We now report the presence of insulin receptors in stromal and follicular compartments as well as in granulosa cells obtained from normal ovaries. After 15-h incubations at 4 C with [125I]insulin and tissue fragments, specific insulin binding was 6-19% and 7-13%/mg protein (n = 8) to stroma and theca, respectively. Granulosa cells obtained in the course of in vitro fertilization were separated from red cells on a Percoll gradient; specific insulin binding ranged from 9-15%/10(6) cells. Insulin binding was characterized by sensitive insulin competition (half-maximal, 10 ng/ml), appropriately shifted proinsulin competition (20 times to the right), and complete inhibition by specific anti-insulin receptor antibodies (B-2). An antibody to the insulin-like growth factor I (IGF-I) receptor (alpha IR-3) that inhibits IGF-I binding to IGF-I receptors in other cell systems had no effect on insulin binding. Further proof that this binding is to classic insulin receptors was obtained from measurement of insulin-stimulated receptor autophosphorylation. When insulin receptors from stroma were extracted with Triton X-100 and incubated with [gamma-32P]ATP and Mn, insulin increased the incorporation of 32P into the beta-subunit of the receptor 5-fold. In parallel studies with [125I-]IGF-I and specific blocking antibodies to its receptor, no detectable IGF-I binding to stroma or follicles was found. We conclude that specific high affinity insulin receptors possessing tyrosine kinase activity are widely distributed in normal human ovary. IGF-I receptors in normal ovary are either absent or present at very low density. Binding of insulin to its own receptor (as opposed to IGF-I receptors) appears to be the most likely first step in the stimulation of ovarian steroidogenesis by insulin in normal ovaries and possibly in insulin-resistant states as well.

Adult↗

Polycystic ovarian disease: sonographic spectrum.

Twenty-eight patients with polycystic ovarian disease (PCOD) as determined by hormonal analysis (with surgical confirmation of the diagnosis in 12 cases) underwent ultrasound examinations. Twenty-nine per cent of patients had normal ovarian volume. Normal ovarian size does not exclude the diagnosis of PCOD in the proper clinical setting. The remaining 71% of patients with PCOD had bilaterally enlarged ovaries in three distinct patterns: discretely resolved cysts (39%), hypoechoic (25%), and isoechoic to the uterus (7%). Understanding the sonographic spectrum of ovarian morphology in PCOD can aid in diagnostic evaluation of this condition in patients who may have a varied clinical presentation.

Adolescent↗

Specific insulin binding sites in human ovary.

The strong association between hyperinsulinemic states of insulin resistance and ovarian hyperandrogenism has led to the suggestion that insulin might directly influence the function of the ovary. To assess this possibility, we have attempted to directly measure insulin receptors in the ovarian stroma of three patients who were operated upon for polycystic ovarian disease. 125I-insulin binding was easily detectable in fragments of ovarian stroma in each case. Specific binding was totally inhibited by pre-treatment with serum containing specific anti-insulin receptor autoantibodies (B-2). These data are consistent with the hypothesis that insulin can directly influence ovarian function. Further studies of insulin receptors and insulin action in human ovarian tissue could lead to a better understanding of the link between insulin resistant states and ovarian hyperfunction.

Adult↗

The diagnosis of ovarian hyperstimulation (OHS): the impact of ultrasound.

Eighty cycles induced by human menopausal gonadotropins in 45 women were studied with serial ultrasound examinations. The incidence of ovarian hyperstimulation (OHS) was 44%, considerably higher than in other series using similar induction protocols. This was probably due to the superior ability of ultrasound to detect ovarian enlargement and the withholding of human chorionic gonadotropin until at least one follicle had reached a minimum size of 15 mm. No difference was found between the mean urinary estrogen levels of those in whom mild or moderate OHS developed and those in whom it did not. It is concluded that the development of OHS is a frequent but acceptable result of ovulation induction.

Amenorrhea↗

Induction of ovulation monitored by ultrasound.

Eighty menstrual cycles were induced by the administration of human menopausal gonadotropin (hMG), and the induction of ovulation was evaluated by serial ultrasound scanning. Ovulation occurred in 57 of these cycles, and pregnancy occurred in 17 patients. No pregnancy occurred if the follicle size was below 15 mm at the time that human chorionic gonadotropin (hCG) was administered. A 15-mm follicle size is, therefore, regarded as a minimum size for a mature ovum. Multiple follicles were present in seven of the cycles where pregnancy occurred, but only two patients had multiple pregnancies. Ovarian hyperstimulation (OHS), which is characterized by cystic ovarian enlargement of greater than 5 cm after ovulation, was present in 25 cycles. This is a considerably higher incidence than previously documented, but since it is not possible to predict reliably its occurrence, and in no patients were the symptoms severe, it is considered an acceptable and inevitable sequela of ovulation induction. The present role of ultrasound is to establish whether the ovary responds to gonadotropin stimulation, to ensure that the follicle has reached a minimum size, to determine the number of preovulatory follicles to inform better the patient about the possibilities of multiple pregnancies, to establish that ovulation has occurred after administration of hCG, and to document the presence or absence of OHS.

Estrogens↗

Sexual function after surgical and radiation therapy for cervical carcinoma.

One hundred women treated for carcinoma of the cervix were interviewed more than one year later to establish the effects of radiation or surgical therapy on sexual function. Forty-three had received irradiation, 44 nonradical surgery, six combined surgery and irradiation, and seven radical surgery. The irradiation and nonradical surgery groups were each further subdivided into subgroups of patients aged 30 to 49 for age-controlled comparison. Patients in the irradiation group had statistically significant decreases in sexual enjoyment, ability to attain orgasm, coital opportunity, frequency of intercourse, and coital desire. The group who had nonradical surgical procedures had no significant change in sexual function after treatment. Similar results were found in both age-controlled subgroups, eliminating age as a major etiologic factor. Marked vaginal alterations were recorded in the majority of irradiated patients, but were not present among the groups treated with nonradical surgery. The vaginal changes alone could not be held accountable for the significant decrease in sexual function among women who received pelvic irradiation. The origin of decreased sexual desire after radiation therapy is complex, and not yet completely understood. We propose therapeutic programs to help women deal with the emotional and physical consequences of pelvic irradiation.

Adult↗

The psychological implications of spontaneous abortions.

Spontaneous abortion occurs in approximately 15% of obstetric patients. Our efforts to decrease bleeding and prevent infection do not take into account the emotional stress of the patient or the sense of grief and loss she might be feeling. Predominantly, the women in this study were concerned with what caused the miscarriage and why it happened. They described themselves as unhappy, depressed, hostile and anxious. In addition, the patients were often misinformed and frequently desired more accurate data. Approximately 25% answered yes to having a psychiatric problem. One-fourth of the patients had been seen earlier in their pregnancies with a threatened abortion; 17.3% had had a previous miscarriage, and 25% felt they were personally responsible for the miscarriage. Recognition of an attention to these facts enables the obstetrician-gynecologist to offer better patient care in the form of reassurance and information at several points of interaction with the patient experiencing a spontaneous abortion.

Abortion, Spontaneous↗

Processing of artificial peptide-DNA-conjugates by the mitochondrial intermediate peptidase (MIP).

Import of DNA from the cytoplasm into the mitochondrial matrix is an obligatory step for an in organello site-directed mutagenesis or gene therapy approach on mitochondrial DNA diseases. In this context, we have developed an artificial DNA translocation vector that is composed of the mitochondrial signal peptide of the ornithine transcarbamylase (OTC) and a DNA moiety. While this vector is capable of directing attached passenger molecules to the mitochondrial matrix, the recognition of this artificial molecule by the endogenous mitochondrial signal peptide processing machinery as well as the cleavage of the peptide plays a pivotal role in the release of the attached DNA. To study the proteolytic processing of the artificial vector, various signal peptide-DNA-conjugates were treated with purified mitochondrial intermediate peptidase. When the leader peptide is directly linked to the DNA moiety without an intervening spacer, MIP processing is prevented. Cleavage of the peptide can be restored, however, when the first ten amino acid residues of the mature part of OTC are appended at the carboxy-terminal end of the signal peptide. Our results show that artificial peptide-DNA-conjugates are recognized by the mitochondrial proteolytic machinery, and therefore an interference of the peptide with the DNA function can be excluded.

Amino Acid Sequence↗

Different patterns of inducible nitric oxide synthase gene expression in ovarian carcinoma cell lines.

BACKGROUND: Stimulation of inducible nitric oxide synthase (iNOS) and release of nitric oxide by tumor cells may play a critical role in cancer development, either by exhibiting tumoricidal effects or by promoting tumor progression. MATERIALS AND METHODS: In the present study, we investigated four ovarian carcinoma cell lines with respect to their iNOS expressing characteristics. RESULTS: Following incubation with interferon-gamma, tumor necrosis factor-alpha and interleukin-1 beta, a marked stimulation of iNOS gene expression was found in SKOV-6 and OVCAR-3 cells, while only minor iNOS synthesis was detectable in HOC-7. Time-dependent accumulation of nitrite/nitrate in the culture supernatant indicated that the three cell lines were stimulated to produce and release nitric oxide. In contrast, no NO generation was observed in the fourth cell line under investigation, 2774. CONCLUSION: Due to the growth regulatory functions attributed to NO, variations in NO production may be of importance e.g. following interferon-gamma therapy in patients with ovarian cancer.

Female↗