Hyperglycosylated HCG expression in pregnancy: cellular origin and clinical applications

Employing a monoclonal antibody (B152) specific for a carbohydrate epitope found on a choriocarcinoma derived hCG, it was discovered that a similar hCG isoform is expressed during early pregnancy. This form differs from later pregnancy hCG in carbohydrate moieties. Profiling of these two hCG isoforms throughout pregnancy utilized two IRMA's: B152-B207 ("hyperglycosylated hCG"-specific assay) and B109-B108 (an IRMA for standard intact hCG isoforms in the WHO hCG reference preparation). The WHO hCG standard was used in both assays. Values were presented as a ratio of hCG isoform concentrations (B152/B109 ratio). In early pregnancy urine concentrations of B152 hCG were significantly higher in normal pregnancy (NP) compared to early pregnancy loss (EPL). Matched serum-urine samples from the first and third trimesters revealed that the B152 hCG form is predominant in both serum and urine in the first trimester compared with the third trimester. The proportion of the B152 hCG (HhCG) form is higher in urine than in matched serum. There was a significant difference in the B152/B109 ratio between days 5 and 20 from time of embryo transfer in normally developing pregnancy versus EPL in the urine of IVF patients. In spontaneous abortion (SA) the level of B109 hCG remained higher in NP compared with SA. However, the B152/B109 ratio declined with gestational age faster in SA than in NP suggesting perhaps a different loss mechanism in SA versus EPL. The cellular origin of the different hCG glycoforms was identified by assay of cell media from cytotrophoblasts (CTBs) and syncytiotrophoblasts (STBs). Isolated CTBs expressed predominantly HhCG. The level of expression was the highest in the first trimester. STBs were the source of the less glycosylated B109 hCG isoform. Analysis of hCG glycoforms during early pregnancy can distinguish pregnancies that will fail from those that will proceed normally. Since the B152 assay does not effectively discriminate between intact HhCG and free beta HhCG (HhCGbeta), a new HhCGbeta assay was developed. This assay recognizes the HhCGbeta which is produced by CTBs. We hypothesize that the measurement of HhCGbeta may have a potential use in screening for Down syndrome and perhaps other pregnancy disorders and certain types of cancer.

Trophoblast origin of hCG isoforms: cytotrophoblasts are the primary source of choriocarcinoma-like hCG

We have previously demonstrated that a hyperglycosylated isoform of chorionic gonadotropin (hCG) (B152 hCG) is detected in the blood and urine in early pregnancy and is subsequently rapidly replaced by the hCG isoform (B109 hCG) characteristic of later pregnancy. In the current study we have extended our work on the origin of these isoforms. We have used a combination of in situ and in vitro approaches. Localization studies in placental tissues showed that monoclonal antibody B109 stained very specifically syncytiotrophoblast (STBs) from first and second trimester tissues. At term, STBs exhibited no B109 staining at all. Immunostaining with B152 antibody, that recognize the hyperglycosylated isoform of hCG, revealed only punctate staining of STBs in most villi of first trimester tissue. Both antibodies B109 and B152 failed to stain cytotrophoblasts (CTBs). To assess the functional relevance of these observations we analyzed conditioned media from purified CTBs using two immunometric assays, one of which (B152-B207*) has primary specificity for the hyperglycosylated, choriocarcinoma-like hCG and the other (B109-B108*) having primary specificity for the later pregnancy hCG isoform. Regardless of gestational age, isolated CTBs secreted predominantly B152 hCG isoform in contrast to placental villi (predominantly STBs), which released primarily the B109 hCG isoform. Isolated CTBs, however, failed to immunostain with both B109 and B152 antibodies. To resolve this contradiction, we cultured CTBs in the presence of brefeldin A, a drug known to block secretion by inhibiting protein translocation from the endoplasmic reticulum to the Golgi vesicles. Brefeldin A treated CTBs stained strongly with B109 and did not stain or stained weakly with B152 antibody. We assume that treatment with brefeldin A impaired glycosylation of beta subunit and consequently inhibited the production of hyperglycosylated form of hCG recognized by B152. In summary, our in vitro experiments indicate that both isoforms of hCG are produced by villus CTBs and that the dominant isoform is the one recognized by antibody B152. STBs produce primarily the less glycosylated B109 hCG isoform. This data suggests that at the beginning of pregnancy villus CTBs are the major source of the B152 hCG isoform. This finding is supported by our clinical data that show that the dominant hCG isoform in the blood and urine of pregnant women in the first 6 weeks of pregnancy is recognized by B152 (). The inversion of the B152/B109 ratio observed after 6-7 weeks of pregnancy can be explained by the reduction of number of villus CTBs and/or by maturation of STBs.

Reliability of serial urine HCG as a biomarker to detect early pregnancy loss

BACKGROUND

To examine the reliability of HCG as a biomarker for early pregnancy loss, five experienced researchers independently assessed data from 153 menstrual cycles, determining whether each cycle represented 'no conception,' a 'continuing conception' or a 'conception lost.'

METHODS

Urine samples were analysed by immunoradiometric assay using a combination of capture antibodies for the intact heterodimer (B109) and for an epitope common to the beta subunit and the beta core fragment (B204). For each cycle, HCG data were presented as graphs of daily assay results. Summary statistics for HCG assays from 46 women who had undergone bilateral tubal ligation represented baseline values.

RESULTS

Pairwise agreement among the assessors for any of the three options ranged from 78-89%. At least three experts agreed for 147 cycles (96%), accounting for 28 conception losses and 19 continuing conceptions. The multi-rater kappa was 0.62 for the conception lost category and 0.68 for continuing conceptions, indicating substantial agreement.

CONCLUSION

The main sources of disagreement involved deciding whether there was sufficient information for assessment, interpreting cycle parameters such as cycle length or bleeding event, and interpreting a distinct HCG rise pattern that does not exceed the baseline value obtained from the sterilized women.

Differential expression of human chorionic gonadotropin (hCG) glycosylation isoforms in failing and continuing pregnancies: preliminary characterization of the hyperglycosylated hCG epitope

Human chorionic gonadotropin (hCG) glycoforms change as pregnancy progresses. We have developed an antibody (B152) which can measure a hyperglycosylated early pregnancy isoform of hCG. This putative hyperglycosylated form of hCG arises very early in pregnancies and is rapidly replaced by an isoform that predominates for the remainder of the pregnancy. The profiles of these hCG glycoforms are measured as a ratio of values of two immunometric assays. The profiles of these ratios differ between pregnancies which persist and those which will experience early failure. In this report, daily urine hCG isoform ratios from donor eggs (no exogenous hCG pretreatment), in vitro fertilization pregnancies were profiled and analyzed from the first day following embryo transfer (ET). Significant differences were found between continuing pregnancy and pregnancy loss throughout days 5-20 post-ET. When hCG isoform ratios were analyzed from the first day of detectable hCG, pregnancy loss could be predicted in the case of a single fetus both during the 5- to 10-day time segment (P=0.018) and the 10- to 15-day time segment (P=0.045). When single and multiple fetus pregnancies were analyzed together significance was approached in the 10- to 15-day time period (P=0.058). In a second population of pregnant women who conceived naturally, in whom urine samples were collected at approximately weekly intervals to either term birth or clinical spontaneous abortion, the ratio could discriminate between miscarriages and normal term pregnancies (P=0.043). In later pregnancy, the ratio of hCG isoforms declined more rapidly in miscarriages than in term pregnancy. Antibody B152 was produced using a choriocarcinoma-derived hCG (C5), which was hyperglycosylated at both N- and O-linked sites and was 100% nicked at position beta(47-48). Western blot analyses supported the assay results showing that early pregnancy urine does not contain nicked C5-like hCG. Also, the early pregnancy hCG appeared to be the same size as later pregnancy hCG as judged by SDS gel electrophoresis. A series of Western blot analyses and immunoassays conducted with the samples either non-reduced or reduced showed that B152 is directed to a linear epitope located in the COOH-terminal peptide region of the beta subunit. This indicated that only the O-glycan groups and not the N-linked glycans are part of the antibody epitope.

Choriocarcinoma-like human chorionic gonadotrophin (HCG) and HCG bioactivity during the first trimester of pregnancy

The objective of this study was to evaluate the distribution of choriocarcinoma-like human chorionic gonadotrophin (HCG) isoforms during first trimester pregnancy and their relationship with in-vitro HCG bioactivity. This was done by means of a retrospective analysis of patients' sera with first trimester normal intrauterine and abnormal (ectopic) pregnancies. Serum samples were obtained from 38 women with an amenorrhoea of <10 weeks. From these, 19 had a normal intrauterine pregnancy (IUP) and 19 an ectopic pregnancy (EP). Total immunoreactive HCG (HCGi), free beta-HCGi and oestradiol were measured by enzyme immunoassays and bioactive HCG by the mouse Leydig cell bioassay. The alterations in HCG isoform content were measured by the combination of two immunometric assays, B152 for choriocarcinoma-like HCG and B109 for intact HCG detection and expressed as the B152/B109 ratio. Choriocarcinoma-like HCG isoforms ratio measured by B152 and B109 assays was significantly higher in the low subgroups of free beta-HCGi and gestational age (P = 0.0111 and 0.0036 respectively). Whereas bioactive to immunoreactive HCG ratios (b/i ratio) were significantly higher when free beta-HCGi concentrations were low (P = 0.0010), no correlation was found between the variation of bioactivity (b/i ratio) and the proportion of choriocarcinoma-like HCG isoforms (B159/B108). It is concluded that in first trimester pregnancies (i) the modulation of HCG in-vitro bioactivity is not related to the variation of choriocarcinoma-like HCG isoforms secretion and (ii) the amount of choriocarcinoma-like HCG isoforms secreted by the early trophoblast is predominant and may be the result of an early developmental regulation of glycosylation enzyme.

The cost-effectiveness of strategies to assess gastroesophageal reflux as an exacerbating factor in asthma

OBJECTIVES

We sought to evaluate the cost-effectiveness of diagnostic strategies to determine whether or not acid reflux exacerbates asthma, and to identify which asthma response probabilities are most important in a cost-effective workup of this problem.

METHODS

We performed a cost-effectiveness analysis, comparing 11 diagnostic strategies to assess the role that acid reflux plays in asthma. Probabilities and costs were derived from the published literature. Average and incremental costs, effectiveness, and cost-effectiveness were calculated for each strategy. Sensitivity analyses were performed.

RESULTS

The most cost-effective diagnostic approach is to begin with omeprazole 20 mg/day for 3 months, followed by 24-h pH testing on drug in nonresponders. If 24-h pH testing is positive, increase the omeprazole dose every 3 months until the patient responds or a maximum of 60 mg/day is given. This strategy costs $730 per case correctly diagnosed. When the cost of pH testing exceeds $586 or the cost of omeprazole 20 mg/day is <$53 per month, omeprazole 20 mg/day for 3 months followed by 60 mg/day for the same duration in nonresponders becomes more cost-effective.

CONCLUSIONS

Empiric acid reflux suppression, followed by pH testing in nonresponders, is the most cost-effective means of determining whether GERD is aggravating a patient's asthma.

Early pregnancy human chorionic gonadotropin (hCG) isoforms measured by an immunometric assay for choriocarcinoma-like hCG

Human chorionic gonadotropin (hCG) exhibits molecular heterogeneity in both its protein and carbohydrate moieties. This communication describes changes in hCG isoforms detected directly in clinical samples. These isoforms, quantified in blood or urine specimens, show a progression of change throughout normal pregnancy. Early pregnancy produces a type of hCG that resembles, in terms of immunoreactivity, a major form of hCG excreted in choriocarcinoma. The isoforms predominate for the first 5-6 weeks of gestation and then diminish, being replaced with the hCG isoforms which predominate throughout the remainder of pregnancy. The alteration in hCG isoform content occurs in both blood and urine. The progression of isoforms is best delineated by calculating the change in the ratio of the two forms, as many hCG assays either do not detect or fail to discriminate among these isoforms. An analogous pattern of hCG isoforms was observed in patients with in vitro fertilization pregnancies. hCG isolated from the pituitary displayed binding characteristics similar to those of the hCG derived from normal pregnancy urine. The early pregnancy hCG isoforms appear to have a differential expression in normal pregnancy as opposed to pregnancies which will not carry to term, suggesting that a determination of the relative balance of hCG isoforms may have diagnostic application in predicting pregnancy outcome.

Evaluation of nicked human chorionic gonadotropin content in clinical specimens by a specific immunometric assay

We report the development and characterization of an IRMA for the direct measurement of nicked human chorionic gonadotropin (hCGn) in blood and urine. hCGn derived from a reference preparation of hCG used as an immunogen elicits monoclonal antibodies (mAbs) with enhanced recognition of human luteinizing hormone epitopes. The most specific assay for pregnancy hCGn is an IRMA composed of one mAb to choriocarcinoma-derived hCGn (C5) and a second mAb developed from immunization with normal-pregnancy hCGn. This assay was used to evaluate hCGn profiles in normal, in vitro fertilization, Down syndrome, and ectopic pregnancies. In all pregnancies, hCGn was usually present in much lower concentrations than the non-nicked hCG isoform. Our results suggest that some form of physical separation from the overwhelming quantities of non-nicked hCG present in clinical specimens will be required before accurate immunochemical estimations of hCGn can be made.

Differential urinary gonadotrophin profiles in early pregnancy and early pregnancy loss

Early pregnancy loss (EPL), detected by patterns of human chorionic gonadotrophin (hCG) in urine, is the biomarker employed in investigations of the impact of personal, workplace or environmental reproductive toxins on human fertility. An issue central to these studies is what, in terms of urinary hCG expression, constitutes an EPL. This report describes the urinary molecular forms of hCG expressed in menstrual cycles in which a normal pregnancy was conceived, or an EPL occurred, or no apparent conception occurred. Qualitative and significant quantitative differences in the expression of hCG-associated analytes were found between normal pregnancy cycles and EPL cycles. Discriminant analysis calculation based on mole fractions of the different hCG-associated molecules afforded 91 per cent and 80 per cent correct classification of clinical pregnancy cycles and EPL cycles, respectively. Although hCG-associated molecules unique to either EPL or normal pregnancy were not found, what is thought to be an early form of hCG is expressed both at a high frequency and at a significantly higher concentration in early normal pregnancy when compared with EPL. The relative absence of this molecule very early in pregnancy may signal a pregnancy loss.

Fluoroscopic examination in the neonatal intensive care unit using an inverted C-arm

Fluoroscopic studies can be performed in the Neonatal Intensive Care Unit (NICU) using a portable C-arm. The C-arm is inverted so that the infant lays directly on the image intensifier. In all our cases, the images obtained were of good enough quality to allow for prompt diagnosis and management of the patient's condition. Furthermore, measured entrance doses were lower using the inverted C-arm than they were using conventional fluoroscopy.

Alcoholic liver disease: proposed recommendations for the American College of Gastroenterology

OBJECTIVE

The objective of this work was to develop practice guidelines for the management of alcoholic liver disease.

METHOD

A computerized search using the Medline Data Base from 1966-July 1997 was performed with the search headings; alcohol, alcoholic hepatitis, alcoholic liver disease, liver transplant, diagnosis, epidemiology, human, and English only. All randomized controlled trials, case-control studies, and meta-analyses were read in depth. A manual search was also done using references from each retrieved report, review articles, editorials, postgraduate course syllabi, and textbooks. In the subsequent review, evidence was evaluated using a hierarchical scale with randomized, controlled trials given the most importance. Abstracts presented at national meetings were included only when unique data were obtained from those studies.

The expression of the urinary forms of human luteinizing hormone beta fragment in various populations as assessed by a specific immunoradiometric assay

Human gonadotrophins undergo metabolic transformations which result in the presence of several smaller, structurally and immunologically related forms of gonadotrophins in the urine. For luteinizing hormone (LH), a beta core fragment (LHbeta cf) has been isolated from the pituitary and characterized. The corresponding urinary fragment is inferred from mass spectral and immunochemical analysis of chromatographically separated urinary forms. Physicochemical characteristics, primarily mass spectral and chromatographic, indicate that the pituitary and urinary forms of LHbeta cf have a different structure, probably in the carbohydrate moieties. This communication characterizes the expression of LHbeta cf in the urine of both reproductive and post-reproductive age women and in men, employing assays highly specific for the pituitary form of the fragment. It was found that LHbeta cf is the predominant LH associated molecular form in the urine during peri-ovulatory period, peaking 1-3 days later than intact LH and reaching a concentration of approximately 600 fmol/mg creatinine, 7-fold higher than either LH or LH free beta subunit. Corresponding concentrations of human chorionic gonadotrophin (HCG) beta cf were <1% that of LHbeta cf. LHbeta cf cross-reaction with some LH or LHbeta monoclonal antibodies may well interfere with the accurate estimation of the day of the LH surge when urinary tests are utilized.

Measuring human chorionic gonadotropin in the absence of implantation with use of highly sensitive urinary assays for intact beta-core and free beta epitopes

OBJECTIVE

To determine if human chorionic gonadotropin (hCG) can be absorbed from the uterine cavity in the absence of an embryo.

DESIGN

Prospective study.

SETTING

University-based assisted reproduction program.

PATIENT(S)

Eight functionally agonadal patients (age range, 33-46 years) who were taking hormone replacement therapy so that they could receive donated oocytes.

INTERVENTION(S)

Intrauterine instillation of 50 microL of hCG (10,000 IU) during a mock cycle before an attempt at oocyte donation.

MAIN OUTCOME MEASURE(S)

Spot urine measurements of different hCG epitopes (intact beta, beta-core, and free beta) at timed intervals (12, 20, 44, and 68 hours after instillation).

RESULT(S)

All hCG epitopes were detected in the urine at the first sampling interval, and levels decreased in subsequent sampling intervals. Measurement of the serum hCG level confirmed that systemic absorption had occurred and that the urine measurements were not a result of specimen contamination through the cervix.

CONCLUSION(S)

hCG may be systemically absorbed into the blood through the uterine cavity, even in the absence of implantation, and its metabolites may be measured with use of highly sensitive urinary assays.

Detecting pre-ovulatory luteinizing hormone surges in urine

The study objectives were to determine (i) if pre-ovulatory luteinizing hormone (LH) surges, undetected in urine by two immunoradiometric assays (IRMA), were detectable by an ultrasensitive immunofluorometric assay (IFMA) and (ii) the influence of creatinine adjustment on the detection and timing of the urinary LH surges. Daily urine specimens were contributed by healthy 25-36 year old volunteers during 14 ovulatory menstrual cycles for an epidemiological study conducted in 1983-1985. Specimens were selected as having been previously assayed by two IRMA without consistently detecting LH surges. These urine specimens were remeasured using an IFMA and adjusted for creatinine concentration. IFMA measurements revealed unambiguous LH surges in all cycles. Adjusting IRMA urinary LH values for creatinine concentrations revealed previously undetected LH surges in four of eight cycles. Creatinine adjustment also altered the timing of IRMA and IFMA LH surges by 1-5 days. These results demonstrate an IFMA that detects pre-ovulatory LH surges in unpreserved, frozen urine from cycles where such surges were previously undetectable. Further, creatinine adjustment can markedly affect detection and timing of the onset and peak of the urinary LH surge. While our analysis suggests that this adjustment improves the validity of the LH measure, this requires further investigation.

Mallet finger

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Characterization of human chorionic gonadotropin in normal and abnormal pregnancies

In this study circulating human chorionic gonadotropin (hCG) levels in the peri-implantation period of natural cycles of normal women were characterized. The hypothesis that the bioactivity of hCG in abnormal pregnancies is different from that in normal pregnancies was tested daily through serum hCG measurements in two immunoenzymometric assays, a radioreceptor assay and a human luteinizing hormone/human chorionic gonadotropin--cyclic adenosine monophosphate--luciferase bioassay. In normal pregnancies, the levels of immunoreactive and bioactive hCG were higher than in abnormal pregnancies (p < 0.05). In addition, the slopes of the rise in concentration of hCG as measured in all four assays were significantly greater for normal pregnancies than for abnormal pregnancies (p < 0.01). The rate of rise of hCG bioactivity was significantly greater than the rise of immunoreactivity or receptor-binding activity in normal pregnancies, but this difference was not observed in abnormal pregnancies. These results indicate that: (1) A steep rise of bioactive hCG is a consistent feature of the peri-implantation period of normal pregnancies. (2) Abnormal pregnancies had a deficiency in the production of hCG, which was reflected in both the hCG levels and the rate of increase, even in the first week of implantation. (3) Some abnormal pregnancies produced hCG with lower biological activity than the hCG of normal pregnancies.

Characterization of human chorionic gonadotropin peptide variants with a radio-receptor assay using recombinant human luteinizing hormone/chorionic gonadotropin receptors

There are potential interactions between various human chorionic gonadotropin (hCG) isoforms at the level of luteinizing hormone/chorionic gonadotropin (LH/CG) receptor. The objective of this study was to characterize the receptor-binding activities of the primary peptide variants of hCG including intact hCG, free beta subunit, beta-core fragment and nicked hCG, and to test the effects of these hCG variants on the binding of intact hCG. A radio-receptor assay based on cell membranes expressing recombinant human LH/CG receptors was validated and used in this study to avoid species differences in the receptor-binding specificity. The results showed that none of the hCG variants that we studied had sufficient binding affinity to compete with binding of intact hCG, nor were they able to antagonize the binding of intact hCG. These results suggest that hCG variants with either abbreviated polypeptide structures or incomplete peptide linkage are products or metabolites which do not have the tropic biological activity of the whole hormone, the intact heterodimeric hCG.

Spinal extramedullary hematopoiesis secondary to hepatocellular carcinoma. Case report and literature review

A 38-year-old man, with hepatitis C and a history of intravenous drug use had hepatocellular carcinoma. Severe low back pain was the result not of metastases but of extramedullary hematopoiesis. This was not confirmed by biopsy but seemed unequivocal on magnetic resonance imaging.

The rise and fall of a radiologic technique

As young radiologists read the slightly self-satisfied articles celebrating the centennial of radiology, they may conclude that the course of radiology and all its components has been smoothly upward, without hesitations, false starts, or disappointments. Older radiologists know better. The replacement of a less satisfactory technique with a better one is a gain for both patients and physicians, but the replacement process itself can be distressing. Much of what radiology residents learned in the 1950s and 1960s is no longer of any use. Who now employs pneumoencephalography or intravenous cholangiography? Entire books were once written about these procedures [1, 2]. Who can now credit the reliance once placed on positive-contrast maxillary antrography [3]? Few have even heard of eustachian tubography [4]. Radiologists who tried to make a career using those techniques learned to their sorrow that although anatomy is permanent and diseases change only slowly, techniques are often ephemeral. Total body opacification, a technique once of consuming interest to the present writers [5-7], is an illustration of this.

Prospective assessment of early fetal loss using an immunoenzymometric screening assay for detection of urinary human chorionic gonadotropin

OBJECTIVE

To develop an economical, nonradiometric immunoenzymometric assay (IEMA) for the detection of urinary human chorionic gonadotropin (hCG) in studies of early fetal loss. To be effective, the IEMA must have a sensitivity equal to the standard immunoradiometric assay (IRMA) and sufficient specificity to eliminate the need for screening most nonconceptive cycles with the expensive and labor-intensive IRMA.

DESIGN

Two different assays were used to measure hCG in daily early morning urine samples from potential conceptive cycles.

SETTING

Women undergoing donor artificial insemination (AI) were evaluated in a prospective study.

PATIENTS, PARTICIPANTS

Ninety-two women volunteers were selected on the basis of apparent normal reproductive health.

INTERVENTIONS

Artificial insemination with nonfrozen donor semen was performed by cervical cup twice each menstrual cycle at 48-hour intervals, and daily urine samples were self-collected throughout the menstrual cycle.

MAIN OUTCOME MEASURES

An IEMA was developed to detect urinary hCG using the same antibodies as in the standard IRMA; a study was designed to determine whether this nonradiometric assay could successfully detect the early fetal loss that was detected by the IRMA.

RESULTS

Of 224 menstrual cycles analyzed by both assays, a total of six early fetal losses were detected by the IRMA. When the tentative screening rule was set to allow all six of these losses and 95% of future losses to be detected by the IEMA, an additional 34 false-positive results were detected by the IEMA. The specificity of the IEMA with this rule was calculated to be 84%.

CONCLUSION

An IEMA based on the same antibodies used for the standard IRMA can serve as an efficient screening assay for the detection of early fetal loss. When the IEMA is used in this manner, nearly 80% of screened menstrual cycles can be eliminated without further testing by the IRMA.

Imaging of musculoskeletal disorders in children

A review of the year's literature on musculoskeletal disorders in infants and children includes many advances in imaging principles, especially MR imaging pulse sequences. We have not attempted to review these advances because the principles are essentially the same in children as in adults. We have confined this review to several topics including the importance of differentiating the findings in osteogenesis imperfecta from those in the abused child, limb-lengthening procedures in infants and children, the treatment of slipped upper femoral capital epiphysis, spinal anomalies, and skeletal abnormalities associated with cloacal exstrophy. A brief comment on cervical spine films in pediatric trauma patients is also included.

Radiographic manifestations of congenital anomalies of the spine

Although the foregoing review of embryologic development and congenital anomalies of the spine in infants and children is necessarily brief, the most commonly encountered abnormalities have been reviewed, and when possible, an attempt has been made to cite the stage of embryologic development at which the various abnormalities originate. As noted, congenital abnormalities of the spine are relatively uncommon but may be of profound clinical significance. During the past decade, the most significant developments in the diagnosis and treatment of these abnormalities have been ultrasonography, CT scanning, and MR imaging. In the neonate, the spinal cord and neural outflow can be evaluated by ultrasonography until the osseous elements begin to fuse. Thereafter, MR imaging is the procedure of choice because it permits evaluation of the spine and spinal cord in all planes of imaging and provides detailed evaluation of the effect of osseous abnormalities on neural structures. Finally, plain radiographs of the spine for evaluation of neonates who have any of a spectrum of sacral dimples are rarely helpful, and in the presence of significant cutaneous or subcutaneous abnormalities, ultrasonography is the preferred modality for evaluation.

The evolution of family medicine resident projects at dalhousie university

The Dalhousie Family Medicine Residency Program has always attempted to meet the research objectives of the College of Family Physicians of Canada. From a "Monitored Reading and Research" program, where projects were encouraged, the department developed a program which involved a mandatory project, preferably involving research, that is formally and objectively evaluated and supervised by faculty. The background, rationale, and problems encountered, as well as attempted solutions, are outlined.

Incidence of early loss of pregnancy

We studied the risk of early loss of pregnancy by collecting daily urine specimens from 221 healthy women who were attempting to conceive. Urinary concentrations of human chorionic gonadotropin (hCG) were measured for a total of 707 menstrual cycles with use of an immunoradiometric assay that is able to detect hCG levels as low as 0.01 ng per milliliter, with virtually 100 percent specificity for hCG in the presence of luteinizing hormone. Our criterion for early pregnancy--an hCG level above 0.025 ng per milliliter on three consecutive days--was determined after we compared the hCG levels in the study group with the levels in a comparable group of 28 women who had undergone sterilization by tubal ligation. We identified 198 pregnancies by an increase in the hCG level near the expected time of implantation. Of these, 22 percent ended before pregnancy was detected clinically. Most of these early pregnancy losses would not have been detectable by the less sensitive assays for hCG used in earlier studies. The total rate of pregnancy loss after implantation, including clinically recognized spontaneous abortions, was 31 percent. Most of the 40 women with unrecognized early pregnancy losses had normal fertility, since 95 percent of them subsequently became clinically pregnant within two years.

Development of highly sensitive immunoassays to measure human chorionic gonadotropin, its beta-subunit, and beta core fragment in the urine: application to malignancies

A variety of malignancies have been associated with the presence of human chorionic gonadotropin, hCG, its subunits, and fragments of its beta-subunit in blood and urine. The usefulness of these hCG-related tumor markers in nontrophoblastic malignancies has been inhibited by inadequate assay techniques. In order to achieve the required sensitivity and specificity, concentration steps and other procedures to remove cross-reacting human luteinizing hormone were necessary. In addition, the coexistence of a fragment of the hCG-beta or beta human luteinizing hormone subunit contributes to significant errors of measurement in urine. The importance of the hCG-beta fragment as a potential tumor marker has been recognized previously but no method was available to measure this antigen readily. We report here the development of a series of radioimmunometric, two-site assays which will accurately measure hCG, hCG-beta subunit, and the beta-subunit fragment directly in small volumes of unprocessed urine. These assays are highly specific, extremely sensitive, and not labor intensive since they employ microtiter plate procedures. Application of these assays to urine samples from patients with gynecological malignancies indicated that over 50% of all patients tested excreted the hCG-beta fragment in their urine. Also, this fragment comprised more than 50% of the moles of hCG immunoreactive components present in the specimens that were positive for hCG. This cancer marker is also demonstrable in trophoblastic malignant states such as choriocarcinoma in which the low molecular weight fragment can also be visualized directly by immunoblotting procedures. We conclude that a search for hCG immunoreactivity in the urine of patients with malignancies will be improved by the inclusion of accurate measurements of the prominent quantities of the beta fragment excreted by these individuals.

Measuring human chorionic gonadotropin for detection of early pregnancy loss

Elucidation of the primary molecular structure of hCG, coupled with monoclonal antibody technology, has permitted the construction of a partial map of hCG surfaces. Based on this information, two-site immunoradiometric assays have been developed which permit the measurement of intact hCG and its subunit molecular forms with unprecedented sensitivity and specificity. These assays have been employed in a determination of the incidence of early pregnancy loss in a normal population with the finding that 22% of all conceptions producing measurable hCG terminate before becoming clinically evident.

Development of an assay for a biomarker of pregnancy and early fetal loss

Human chorionic gonadotropin (hCG) is a glycoprotein hormone, secreted by the syncytiotrophoblast cells of the fertilized ovum, that enters the maternal circulation at the time of endometrial implantation. It is composed of two nonidentical subunits; alpha and beta, with molecular weights of 14 kD and 23 kD, respectively. Its alpha subunit is identical in primary structure to its glycoprotein homologs, luteinizing hormone (LH), follicle-stimulating hormone (FSH), and thyroid-stimulating hormone (TSH). Human chorionic gonadotropin binds to the same receptor as hLH and displays the same biological response, namely, to stimulate the declining function of the corpus luteum to produce progestins and estrogen late in the menstrual cycle. The differences in the structures of hCG and hLH have been exploited to develop antibodies that can measure hCG specifically in the presence of hLH. Two-site antibody binding assays have been developed, based on a surface immunological concept of hCG epitopes, that involve four distinct regions to which antibodies against hCG can bind simultaneously. Antibody cooperative effects, in conjunction with kinetic advantages derived from the concentration factors by use of the sandwich assay technique (immunoradiometric assay, IRMA), have enabled development of extremely sensitive and specific measurement protocols for urinary hCG. The assay described herein permits the detection of pregnancy on an average 25.4 days after the first day of the preceding menses, as opposed to 29.5 days for conventional radioimmunoassay techniques. In addition, the greater sensitivity and specificity of this assay method has permitted the detection of episodes of fetal loss not detected by radioimmunoassay of urine specimens. A large scale epidemiological study is in progress using this assay technique as a way to identify pregnancies that are lost before becoming clinically apparent. This methodology provides a valuable tool for the determination of the rate of early fetal loss.

A technique for radiographic cannulation and opacification of anatomical structures with small orifices--a new method

A technique for the injection of contrast material into structures with small orifices which cannot be catheterized in the usual manner is described and illustrated. A small occlusion balloon catheter (Medi-Tech, Watertown, MA) allows for orifice cannulation and occlusion for retrograde contrast examination.

Persistent incompetence of the cervix in female infants with congenital abnormalities of the pelvic viscera and perineum

Vaginal reflux during voiding cystourethrography (VCUG) is a common finding in young females. Reflux of urine into the uterus, fallopian tubes, and peritoneal cavity documented by contrast studies is rare and considered abnormal. Chronic retrograde flow of urine and its contaminants through an incompetent cervical os mechanism into the peritoneal cavity may lead to peritonitis, pelvic inflammatory disease, and sterility. Five females with congenital abnormalities of the pelvic viscera and perineum had reflux into the uterus, fallopian tubes, and/or peritoneal cavity during voiding studies done before or months to years after successful corrective surgery. The findings were compatible with a persistent incompetent cervical os. It appears that this group of patients is at risk for the development of chronic pelvic inflammatory disease and its consequences.

Emergency management of pediatric head injuries

About a quarter of a million children are hospitalized each year in the United States because of head injuries, with many more than that treated outside the hospital. Although the majority of children with head trauma appear to recover fully, with or without treatment, a significant minority suffer neurologic residua and several thousand such children die annually. Thus, especially in more seriously injured children, the emergency treatment of the child may be crucial to the eventual outcome. In this review, an approach to the emergency management of pediatric head injuries is presented. The full assessment of the child--by means of a thorough history, physical and neurologic examinations, and appropriate diagnostic tests--is reviewed. The need to treat the whole child, searching for associated injuries of the spine, chest, abdomen, and limbs accompanying those to the head, is stressed. General supportive care of the child, including management of respiratory and circulatory systems, as well as specific treatment of raised intracranial pressure and post-traumatic seizures, is described. The clinical presentations of scalp injuries, skull fractures, cerebral concussion, cerebral contusion and laceration, and acute epidural and subdural hematomas are outlined and their treatments discussed.

Effect of tamoxifen treatment on estrogen metabolism in postmenopausal women with advanced breast cancer

The effect of tamoxifen therapy on plasma estrone and estradiol concentration, urinary excretion of estrone, estradiol, and estriol glucuronides, and metabolism of a tracer of 3H-estradiol was studied in 12 postmenopausal women with metastatic breast cancer. The most striking change observed was consistent increase in the 72-hour urinary recovery of total radioactivity after the tracer, from a mean of 47% to a mean of 61% of the dose. This increase was accounted for by a corresponding increase in the recovery of total glucuronide radioactivity, from a mean of 32% to a mean of 44% of the dose; there was no change in the proportions of estrone, estradiol, estriol, or 2-hydroxyestrone in the glucuronide fraction. The most likely explanation for this finding is that the estrogen-receptor-blocking effect of tamoxifen decreases estrogen uptake by various tissues and permits the estrogen to be excreted in the urine instead. There was also a small but consistent and significant decrease in plasma estrone (from 47 to 36 pg/ml) and estradiol (from 15 to 13 pg/ml), with no change in urinary excretion of estrogen glucuronides. The drop in plasma estrogen levels without a decrease in estrogen production suggests that tamoxifen may increase the metabolic and/or renal clearance of estrogen metabolites. There was no correlation between the observed effects of tamoxifen and the pretreatment estrogen-receptor status of the patient or her response to tamoxifen therapy.

Unusual roentgenologic manifestations of Meckel's diverticulum

Five cases illustrating rare roentgenographic manifestations of Meckel's diverticulum are presented. Small bowel studies in 2 patients demonstrated a mucosal pattern identifiable as heterotopic gastric rugae, and in 2 other cases peptic ulcers were seen within the diverticulum. In 1 patient the diverticulum located in the right upper quadrant contained calcified enteroliths, and in another patient the diverticulum had fistulous communication with the appendix.

Beta-thromboglobulin levels in relation to myocardial infarction--preliminary observations

34 patients with myocardial infarction were studied with daily measurements of beta-thromboglobulin (BTG) and 125I fibrinogen scanning in order to detect deep-venous thrombosis (DVT). Serial levels of BTG were unhelpful in the early detection of this condition, which occurred in 7 of the patients studied. 5 of the patients with DVT had received prophylactic heparin and 6 of them were non-smokers. This latter observation is in support of previous studies suggesting an increased incidence of DVT after myocardial infarction in non-smokers as compared to smokers.

Multiple genitourinary abnormalities in females with unilateral renal agenesis: three cases

We have the means to identify over 75% of infants and children with unilateral renal agenesis. It has been established that all patients with unilateral renal agenesis must be followed closely because of problems with the remaining kidney and other anomalies. It is apparent from embryologic studies and numerous reports that up to 89% of females with unilateral renal agenesis are likely to have significant accompanying genitourinary abnormalities. Most of these patients' genital problems occur at the time of puberty or pregnancy. Because of our experience with three teenage females who had unilateral renal agenesis and subsequent serious problems, we wish to advocate a prepubertal aggressive investigation.

Beta thromboglobulin and glycosylated haemoglobin in diabetes mellitus

No correlation has been demonstrated between the elevated levels of plasma beta-thromboglobulin and glycosylated haemoglobin found in a group of 97 diabetic patients. The abnormality in diabetic platelets which is reflected by beta-thromboglobulin levels may not therefore be a direct result of poor metabolic control. The highest levels of beta-thromboglobulin were found in those patients with a raised blood urea. Glycosylated haemoglobin levels correlated with prevailing blood glucose and with the type of therapy employed, and were highest in the insulin dependent diabetics, intermediate in those on tablets and lowest in those on diet alone.

Voiding cystourethrography in infants and children: a new technique

A technique for voiding cystourethrography utilizing a small caliber (3.5 Fr.) catheter that is left in place during the entire examination is described and illustrated. Urethral pathology is not obscured. The contrast is infused under pressure applied with a blood administration set. Visualization of voiding can be achieved in all cases.

Aicardi's syndrome; radiologic manifestations

Features of Aicardi's syndrome include infantile spasms associated with pathognomonic chorioretinopathy, abnormalities of the corpus callosum with heterotopia of gray matter, and characteristic electroencephalographic findings. Vertebral abnormalities are also part of the syndrome, which is apparently limited to female infants. Subnormal mental development appears in all cases. It was first described in 1969 in French. Isolated cases in the literature have been associated with facial asymmetry, plagiocephaly, and the Dandy-Walker syndrome. Experience with two patients suggests that a search for cases among patients with chorioretinopathy and infantile spasms will show the syndrome to be more common than currently reported.

Surgical management of thirty-nine children with lymphedema

Thirty-nine children underwent staged excisional surgery for lymphedema. The procedures are described in detail. All the children operated on have improved and have a more normal appearance. The decrease in attacks of cellulitis and lymphangitis is striking. The morbidity of this simple procedure is negligible. The operation is tedious, fatiguing, anatomically unexciting, and has a vague end-point. At this time, staged subcutaneous excision appears to be the procedure of choice in moderate to severe lymphedema in children regardless of etiology or classification. The procedure is not a cure.

Peroral removal of a sewing needle and attached thread from the esophagus in an infant

The authors describe a simple Seldinger Catheter technique by which they removed a metallic sewing needle with attached thread from the esophagus of a 5 month old infant.