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Recent reports have suggested that maternal antibodies to specific epitopes of the variable region 3 (V3 loop) of gp120 of HIV-1 might protect against perinatal transmission. In an attempt to confirm these findings, sera from 34 HIV-1-seropositive mothers, representing 13 episodes of mother-to-infant transmission and 23 episodes of non-transmission (two mothers had two pregnancies each during the study period), were tested for the presence of antibodies to various regions of the gp120 V3 loop. Synthetic peptides were generated from HIV-1MN. Of the four peptides tested by enzyme-linked immunosorbent assay (ELISA), only antibody to the C53 peptide (Env310-322, principal neutralizing determinant) was present in maternal sera. Antibody to the C53 sequence was present in 11 specimens from transmitting mothers and 21 from non-transmitting mothers (84.6 and 91.3%, respectively, P = 0.6). No reactivity was detected against the C51, C57, or C58 peptide sequences, located on the sides of the V3 loop. In an antigen-limited ELISA, only two specimens from transmitting mothers and two specimens from non-transmitting mothers had detectable 'high-affinity' antibodies to C53 at low antigen concentrations (15.4 and 8.7%, respectively; P = 0.6). Our results do not support previous reports that epitope-specific antibodies to the V3 loop peptides protect against perinatal transmission. Further research is required to determine whether any specific maternal humoral response might influence HIV-1 perinatal transmission.

We present a simple, efficient extension of denaturing gradient gel electrophoresis that allows the detection of nearly any sequence change in a defined fragment of DNA. The fragment can be obtained either by means of the polymerase chain reaction or by restriction digestion of genomic DNA. With restriction fragments of genomic DNA, sequence information is not required, and covalent modifications in genomic DNA that are lost in a PCR, such as methylation, are detectable. We describe how a GC clamp (an arbitrary, G+C-rich sequence of 30 to 60 bp) can be attached to a selected restriction fragment present in a digest of genomic DNA. The GC clamp alters the melting properties of the fragment; this change greatly increases the fraction of possible mutations that is detectable. In a 272-bp HaeIII fragment from the human beta-globin gene, we were able to detect 13 of 13 mutations tested in human genomic DNA. Four additional mutations in cloned plasmids were analyzed. The data agree with a simple theoretical model for DGGE, which predicts how two fragments, differing at a single (specified) base pair, are resolved in a gradient gel as a function of running time for the gel. The calculation assists in the design of probes and gel conditions that aid in the detection of sequence changes.

The early diagnosis of infection with human immunodeficiency virus (HIV) in infants born to infected mothers is essential for early treatment, but current tests cannot detect HIV infection in newborns because of the presence of maternal antibodies. We used the polymerase chain reaction, a new technique that amplifies proviral sequences of HIV within DNA, to detect HIV infection in peripheral-blood mononuclear cells obtained from infants of seropositive women during the neonatal (age less than 28 days) and postneonatal periods. In blood obtained during the neonatal period, the polymerase chain reaction was positive in five of seven infants in whom the acquired immunodeficiency syndrome (AIDS) later developed (a mean of 9.8 months after the test). The test was also positive in one of eight newborns who later had nonspecific signs and symptoms suggestive of HIV infection (mean follow-up, 12 months). No proviral sequences were detected in neonatal samples from nine infants who remained well (mean follow-up, 16 months). HIV proviral sequences were detected in samples obtained during the postneonatal period (median age, five months) in all of 6 infants tested who later had AIDS and in 4 of 14 infants with nonspecific findings suggestive of HIV infection. No proviral sequences were detected in 25 infants who remained well (mean follow-up, 17 months) after being born to HIV-seropositive mothers, or in 15 infants born to HIV-seronegative mothers. We conclude that the polymerase chain reaction will be a useful technique to diagnose HIV infection in newborns and to predict the subsequent development of AIDS. However, larger studies will be required to determine the sensitivity and specificity of the test.

Abnormal coagulation studies indicative of a dysfibrinogen were found in the plasma of four of seven patients with malignant hepatoma. The abnormal fibrinogen was characterized by prolonged prothrombin, thrombin and reptilase times and inhibition of the coagulation of normal plasma. Purified fibrinogen revealed abnormalities similar to those in plasma. The functional defect was one of delayed polymerization of the fibrin monomer. The carbohydrate content of the abnormal fibrinogen was increased, and this change was related to the abnormal fibrinogen function. Enzymatic cleavage of sialic acid from the abnormal fibrinogen restored fibrinogen function to normal. This hepatoma-associated dysfibrinogen (acquired dysfibrinogenemia) is similar in many respects to fetal fibrinogen and may represent the presence of a fetal form of fibrinogen in hepatoma.

To estimate the cost of hospital care for children infected with the human immunodeficiency virus (n = 37) at Harlem Hospital Center, New York, a cost-based inventory of medical resource consumption was developed. Six thousand thirty-five inpatient days were audited by retrospective chart review. The total cost of care between 1981 and 1986 was +3,362,597. Average lifetime costs were +90,347 per child. One third of the total inpatient days and over 20% of the cost resulted from social rather than medical factors. Per diem costs were highest for children with opportunistic infections (+705) and lowest for homeless "boarder babies" (+466). Boarder babies had a mean length of stay nearly four times longer than those with homes (339 days vs 89 days). The primary predictors of length of stay were maternal intravenous drug use and boarder baby status, regardless of medical need. The unique needs of human immunodeficiency virus-infected children require innovative medical, social, and financial solutions.