Neurotrophin receptors in the somatosensory cortex of the mature rat: co-localization of p75, trk, isoforms and c-neu.

Trk immunoreactivity is expressed by a discrete population of cortical neurons, primarily those with cell bodies in layer Vb and dendrites in supragranular cortex. We tested the hypothesis that neurons co-express multiple isoforms of trk receptors. The distribution of neurons expressing specific high affinity neurotrophin receptors was determined immunohistochemically. Multiple antibodies directed against each trk isoform and an antibody directed against an epitope shared by all three trk isoforms were used. The distribution of neurons expressing each of the three receptors was virtually identical. Each anti-trk antibody primarily labeled neurons with cell bodies in layer V. More than one-third of layer V neurons was positive for a high affinity trk receptor. Few immunoreactive somata (1%-5%) were in the other layers. In addition, the neuropil in the supragranular laminae was immunopositive for each trk isoform. Recent data show that layer V neurons in the mature somatosensory cortex express the tyrosine kinase receptor c-erbB2, also known as c-neu. Immunofluorescence double labeling shows that approximately 80% of the c-neu-immunolabeled neurons in layer V co-expressed pan-trk immunoreactivity and two-thirds of all c-neu-positive neurons expressed a specific trk isoform. We concluded from these data that there is significant co-expression of trk isoforms in layer V neurons. In summary, trkA, trkB, trkC, and c-neu were primarily expressed by cortical projection neurons in layer V and co-expression among these receptors was common. This implies that cortical growth factor systems are redundant and that cortical neurons are responsive to more than one growth factor.

Comrades in adversity: the group approach.

Women suffering postnatal depression frequently report the additional stress of feeling they are alone in their distress. Access to a regular support group to discuss their problems with peers can be valuable. Fawnia Pitts describes one such health visitor-led group, evaluation of which suggests it is both effective and cost-efficient in helping women through postnatal depression.

Improvement of four patients with HIV-1 related symptoms after hyperimmunization with killed poliomyelitis (Salk) vaccine.

Four HIV-1 positive patients with characteristic symptoms of this infection experienced amelioration or resolution of symptoms after 2 months of hyperimmunization with inactivated (Salk) poliomyelitis vaccine. The patient who was initially the most symptomatic exhibited a marked improvement in T4/T8 ratio at the sixth month of continued hyperimmunization treatment. With two patients reported previously, six consecutive patients with lymphotropic retrovirus disease have benefited from hyperimmunization with inactivated polio vaccine.

Clinical improvement of two patients with T lymphotropic retrovirus diseases after polio vaccine hyperimmunization.

Patients with acute leukemia have an impaired ability to produce antibodies to poliovirus in response to inoculation with inactivated vaccine. Reimmunization will, however, produce a relative increase in antibodies equivalent to that of healthy subjects. A child with acute lymphocytic leukemia was hyperimmunized with Salk polio vaccine following a relapse and has had no further relapse nor sequelae for 20 years. An adult physician with acquired immunodeficiency syndrome hyperimmunized himself with the same vaccine, and the preliminary results are encouraging. The clinical improvement seen in these two patients following hyperimmunization with killed polio vaccine may reflect a secondary immune amplification that has been observed in humans following live polio virus immunization.

Dexamethasone suppression in depressed elderly outpatients.

The dexamethasone suppression test (DST) was performed as part of the preliminary workup in 85 previously untreated outpatients with major affective disorder, unipolar depressive type, who were over age 60. All patients were given a systematic structured interview (NIMH-DIS), and all had scores over 20 on the 21-item Hamilton Depression Rating Scale (HAM-D). Only 12 patients (14%) had positive DSTs; more of the non-melancholic (6 of 25; 24%) than melancholic (6 of 60; 10%) patients failed to suppress serum cortisol following standard dexamethasone challenge (p less than .10). DST results did not correlate with patients' HAM-D or Zung depression scores, gender, response to treatment, or any other variable studied. These findings suggest that, in comparison to previous reports, a positive DST may be 1) less common in major depressive disorders, 2) no more common in more severely depressed patients, and 3) less relevant to indications for specific treatment.

PCP in amniotic fluid and breast milk: case report.

The presence of phencyclidine (PCP) in breast milk and amniotic fluid of a young drug abuser is described. Implications drawn from these data include the possible use of amniocentesis in women with well-documented histories of drug abuse who have low levels of PCP in urine, and the restriction of breast feeding in women who have abused PCP.

Phencyclidine in umbilical cord blood: preliminary data.

The epidemic abuse of phencyclidine (PCP) has become a major psychiatric issue within the past decade. With the assistance of highly sensitive capillary gas chromatographic-nitrogen detector measurements, PCP's true pervasiveness is only now being appreciated. To further quantitate the severity of the problem, the authors analyzed samples of umbilical cord blood from 200 patients on the obstetrics service of a major university medical center. Preliminary results revealed that 24 (12%) of the samples were positive for PCP (.10-5.80 ng/ml). The authors discuss the significance of this finding with regard to psychiatry, obstetrics, pediatrics, and juvenile law.