Biomedical subjects

R Samadi

Publications and source records attributed to R Samadi.

5 recordsLinked to original sources

PubMed2001

Evaluation of a rapid optical immunoassay-based test for group B streptococcus colonization in intrapartum patients.

OBJECTIVE: To compare an optical immunoassay (OIA) rapid diagnostic kit to standard culture for the diagnosis of vaginal colonization with group B streptococcus (GBS) and to assess the accuracy and reproducibility of the OIA results. METHOD: A total of 301 patients in labor were prospectively evaluated for GBS colonization with a test approved by the Food and Drug Administration (STREP B OIA kit, Biostar, Boulder, CO, USA) and by culture. The vagina was simultaneously sampled with two swabs. Rectal culture was obtained separately. RESULTS: By the criterion of a positive culture, the vagina was colonized by GBS in 33 of 301 (11%) patients; and the rectum in 42 of 301 (13.9%). The vagina or rectum or both were colonized by CBS in 54 of 301 (17.9%) of patients. The OIA had sensitivity, specificity, positive predictive value and negative predictive value of 63.6%, 86.3%, 37.5% and 94.8%, respectively. The OIA had a kappa statistic score of 0.59. CONCLUSION: The OIA is not an adequately sensitive rapid kit for reliable detection of GBS colonization of the vagina. The results of the OIA were only moderately accurate and reproducible.

Cell Culture Techniques↗

PubMed1998

Stillbirth evaluation: what tests are needed?

OBJECTIVE: We sought to investigate what aspects of the stillbirth evaluation are considered to be essential and what tests can potentially be eliminated. STUDY DESIGN: A retrospective analysis of 745 stillbirths occurring from January 1990 to December 1994 was conducted. A stillbirth was defined by an estimated gestational age >20 weeks' gestational age or fetal weight >500 gm. We attempted to arrive at an apparent cause for each stillbirth after evaluation of genetic or chromosomal abnormalities, obstetric history, maternal medical illnesses, laboratory tests, autopsy findings, and placental pathologic conditions. RESULTS: We found that the most important aspects of stillbirth evaluation were placental pathologic conditions and autopsy. When the placenta was examined, a significant abnormality was detected in 30% (160 of 529) of the cases. When autopsy was performed, only 31% of fetal deaths (142 of 462) were unexplained; however, when no autopsy was performed, 44% (125 of 283) were unexplained (p = 0.0002). The following laboratory evaluations that were routinely performed were found to yield little definitive information: antinuclear antibody testing, Kleihauer-Betke test, and screening for congenital infections (toxoplasmosis, other viruses, rubella, cytomegalovirus, and herpes simplex virus). Overall, 36% (267 of 745) of stillbirths still remained unexplained despite a thorough evaluation in most cases. CONCLUSION: The causes of stillbirth are many and varied, with a large proportion having no obvious cause. As this study demonstrates, certain laboratory tests can be eliminated in the workup of fetal death. In the evaluation of stillbirth a complete systematic method that incorporates placental pathologic conditions, as well as autopsy findings, should prove to be beneficial.

Adolescent↗

PubMed1986

Immunohistochemical localization of intermediate filament proteins of neuronal and nonneuronal origin in the goldfish optic nerve: specific molecular markers for optic nerve structures.

The predominant proteins (58K) of the intermediate filament complex in the goldfish visual pathway consist of a series of isoelectric variants. Previous biochemical studies have shown that proteins ON1 and ON2 are of neuronal origin, whereas ON3 and ON4 are of nonneuronal origin. Polyclonal antibodies, purified by affinity chromatography, that are specific for ON1 and ON2 or ON3 and ON4 have been used to localize histologically the ON proteins within the normal and crushed optic nerve. Anti-ON1/ON2 antiserum presented a pattern consistent with intraaxonal staining. A nonneuronal staining pattern was observed with anti-ON3/ON4 antiserum. The two patterns were distinct from and complementary to each other. The data suggest that ON3 and ON4 represent a novel glial fibrillary acidic protein. The results are discussed in terms of the function of these proteins in development, plasticity, and regeneration.

Animals↗

PubMedDate not supplied

Significance of antinuclear antibody testing in unexplained second and third trimester fetal deaths.

The purpose of this study was to determine if a group of patients with unexplained second or third trimester fetal demise have an increased prevalence of antinuclear antibodies (ANA) when compared to controls. During a 5-year period from January 1989 through December 1993, the records of all fetal deaths > or = 500 g or > or = 20 weeks of gestation that occurred at our institution were reviewed. In these women the ANA titers were checked at the discretion of the physician. The proportion of positive ANA tests in the group of women with explained fetal deaths was compared to that in women with unexplained fetal deaths. These results were then compared to a control group of healthy gravidas presenting to labor and delivery in the third trimester. During this time period, 848 fetal deaths were recorded. Our study population consisted of 286 patients who had an unexplained second or third trimester fetal demise with a record of having an ANA drawn. Of the 376 explained fetal deaths, 190 had an ANA assayed. The control group included 299 healthy third trimester gravidas. In the group of patients with unexplained fetal death, 11.5% (33/286) had a positive ANA, whereas 16% (31/190) of ANA tests were positive in cases of explained fetal death (P = 0.17). In the control group, 14% (43/299) had a positive ANA. There were three distinct immunofluorescence patterns: nucleolar, speckled, and homogeneous. The first two were seen more often in the control group, whereas the latter was seen more frequently in those patients with fetal death (P = 0.10). The incidence of a significant circulating ANA titer was similar in patients and controls. Moreover, there was no significant association between circulating antinuclear antibody titers and fetal outcome. More patients with a fetal death had a homogeneous nuclear fluorescence pattern when compared to controls; however, this finding was not statistically significant. Therefore, we do not recommend routine testing for ANA in women with unexplained second or third trimester fetal death.

Adolescent↗

PubMedDate not supplied

Massive fetomaternal hemorrhage and fetal death: are they predictable?

OBJECTIVE: To report the incidence of massive fetomaternal hemorrhage (FMH) associated with fetal death and to test the hypothesis that FMH is more likely to occur in those with risk factors for FMH. STUDY DESIGN: All cases of fetal death of infants weighing > 500 gm between January 1, 1990 and December 31, 1994 were reviewed for evidence of massive FMH (> or = 2% fetal cells in the maternal circulation as measured by the Betke-Kleihauer test). Women with risk factors were compared with those without risk factors with respect to the occurrence of massive FMH. RESULTS: The prevalence of massive FMH was 14 of 319 (4.4%) cases, occurring in 4 of 102 (3.9%) of those with risk factors and 10 of 217 (4.6%) of patients without risk factors (p = 0.78). Otherwise unexplained fetal death was associated with massive FMH in 5 of 141 (3.5%). Major fetal anomalies were present in 5 of 14 (35.7%) cases of massive FMH. CONCLUSION: Clinical risk factors do not predict an increased likelihood of massive FMH. Massive FMH is associated with fetal anomalies. Betke-Kleihauer testing should be performed in all cases of fetal death, including those with anomalies regardless of the presence or absence of risk factors for FMH.

Adolescent↗