Behavioral and developmental changes associated with prenatal opiate receptor blockade

Pregnant Long-Evans hooded rats were dosed with 1, 5, or 10 mg/kg per day naloxone from gestational day 7 (GD7) through GD20. The control groups included both uninjected animals and injected animals pairfed to the 10-mg dose animals. At birth, all litters were culled to four males and four females, and fostered to undosed surrogate dams. Prenatal naloxone exposure produced changes in body weight development, pain sensitivity, and motor behavior in the offspring. Five and 10 mg/kg naloxone increased adult body weights in females only, as did the pairfeeding condition. The 10 mg/kg naloxone altered pain sensitivity (in males only) as measured by the tail flick test. Animals in the 1 mg/kg dose condition habituated more rapidly than uninjected (UN) subjects in the open field, and showed less activity than UNs as they matured. Bar pressing rates were reduced in the 10 mg/kg dose males in a visual discrimination task, while 10 mg/kg males and females showed reduced bar pressing rates on differential reinforcement of low rates of responding (DRL). These findings confirm that prenatal exposure to naloxone alters some aspects of neurobehavioral development in the rat, and are consistent with the hypothesis that 1 mg/kg prenatally may increase opiate function in offspring, while 10 mg/kg prenatally may decrease opiate functioning in the offspring.

Linkage of early-onset osteoarthritis and chondrocalcinosis to human chromosome 8q

Calcium pyrophosphate-deposition disease (CPDD), also called "chondrocalcinosis" or "pseudogout," is a disorder characterized by the deposition of calcium-containing crystals in joint tissue, which leads to arthritis-like symptoms. The presence of these crystals in joint tissue is a common finding in the elderly, and, in this population, there is a poor correlation with joint pain. In contrast, early-onset CPDD has been described in several large families in which the disease progresses to severe degenerative osteoarthritis (OA). In these families, an autosomal dominant mode of inheritance is observed, with an age at onset between the 2d and 5th decades of life. In this report, we describe a large New England family with early-onset CPDD and severe degenerative OA. We found genetic linkage between the disease in this family and chromosome 8q, with a multipoint lod score of 4.06. These results suggest that a defective gene at this location causes the disease in this family.

Mixed-lineage acute myeloid leukemia associated with a suprasellar dysgerminoma

An association between primary mediastinal germ cell tumors and hematologic malignancies has been recognized since 1985. We present a patient with a suprasellar germ cell tumor and an associated leukemia. A 20-year-old black female presented in December 1987 with a 6-month history of headaches and weight loss, confusion, polyuria, and polydipsia. Evaluation revealed hypernatremia, normal neurologic examination except poor recall, and an enhancing inhomogeneous suprasellar mass on cranial computed tomography. Biopsy of the mass diagnosed a dysgerminoma, which was treated with craniospinal radiation. In February 1988, the patient developed pancytopenia, which resolved with discontinuation of cimetidine and phenytoin. She did well until June 1988 when she presented with skin lesions over the trunk and extremities. Skin biopsy revealed a leukemic infiltration. She was admitted with a WBC 1,500/microliter (without blasts), Hb 11.6 g/dl, PLT 210,000 microliter. Bone marrow biopsy revealed hypercellularity with 50% blasts, demonstrating mixed-lineage acute myeloblastic leukemia (myelomonocytic-M4; megakaryoblastic-M7). The patient was induced with a standard Ara-C/daunorubicin regimen. Two weeks postinduction, she became septic and expired. An autopsy demonstrated leukemic involvement of the spleen, liver, bone marrow, and skin, without residual dysgerminoma. This represents the first reported case of suprasellar dysgerminoma associated with a mixed-lineage leukemia not related to chemotherapy.

Liver resection for colorectal liver metastases

The management of patients with colorectal liver metastases is still controversial. Recent evidence suggests benefit for resection of localized metastases within a single lobe of the liver. A series of 49 patients undergoing liver resection for localized liver metastases is presented. Resection involved right hepatectomy (23), left hepatectomy (8) and segmental excision (18). The median age was 62 (range 40-77). Patients have been followed for a period of up to seven years. The overall median survival was 24 months. The actuarial 3-year survival was 57.9%. There was no significant correlation of survival with the degree of differentiation or Dukes staging of the primary tumour. This series adds further weight to the evidence supporting resection in selected patients with colorectal liver metastases.

Joint CNS appointment: is it viable?

A CNS joint appointment that is supported by the departments of nursing and medicine is viable when goals of the nurse and the organizations are congruent and expectations are delineated. Many challenges and strategies are associated with a joint appointment. Although the challenges and strategies were similar for the first (C.N.) and second authors (L.A.), their experiences differed. Based on the experience of the authors, feasibility of a joint appointment and benefits, challenges, and strategies for enacting the role are presented.

22 genes from chromosome 17q21: cloning, sequencing, and characterization of mutations in breast cancer families and tumors

In our effort to identify BRCA1, 22 genes were cloned from a 1-Mb region of chromosome 17q21 defined by meiotic recombinants in families with inherited breast and/or ovarian cancer. Subsequent discovery of another meiotic recombinant narrowed the region to approximately 650 kb. Genes were cloned from fibroblast and ovarian cDNA libraries by direct screening with YACs and cosmids. The more than 400 cDNA clones so identified were mapped to cosmids, YACs, and P1 clones and to a chromosome 17 somatic panel informative for the BRCA1 region. Clones that mapped back to the region were hybridized to each other and consolidated into clusters reflecting 22 genes. Ten genes were known human genes, 5 were human homologs of known genes, and 7 were novel. Each gene was sequenced, compared to genes in the databases to find homologies, and analyzed for mutations in BRCA1-linked families and tumors. Eight mutations were found in tumors or families and not in controls. In the gene encoding alpha-N-acetylglucosaminidase, approximately 100 kb proximal to the 650-kb linked region, somatic nonsense, missense, and splice junction mutations occurred in 3 breast tumors, but not in these patients' germline DNA nor in controls. In an ets-related oncogene in the linked region, a missense mutation cosegregated with breast cancer in one family and was not observed in controls. In a human homolog of a yeast pre-mRNA splicing factor, 3 different mutations cosegregated with breast cancer in 3 families and were not observed in controls. In these and the other genes in the region, 36 polymorphic variants were observed in both cases and controls.

Effects of oltipraz and related chemoprevention compounds on gene expression in rat liver

One promising approach to cancer chemoprevention involves the induction of phase II xenobiotic metabolism enzymes. Since this approach requires drugs specifically intended to alter tissue gene expression patterns over long periods, it will be important to determine experimentally which proteins are increased or decreased by treatment, and how such alterations may (or may not) be related to the postulated chemopreventive mechanism. We have employed two-dimensional electrophoresis to detect and quantitate gene expression effects of candidate chemoprevention compounds in the livers of treated rats. Oltipraz, an inducer of several phase II enzymes, affected a series of at least 26 proteins, most of which were slightly decreased by treatment. Several proteins were increased, the prime example being rat liver spot 693, which was induced more than 7-fold by oltipraz. This protein was excised from multiple 2-D gels and subjected to in situ tryptic digestion followed by microchemical sequence analysis. The resulting multiple peptide sequences match perfectly with the cDNA-derived sequence of rat aflatoxin B1 aldehyde reductase (AFAR). Using quantitative measurements of AFAR from 2-D gels, we compared a series of dose regimens. Oltipraz administration by gavage or in diet appeared equally effective, while recovery studies indicated a half-time of 5.5 days for disappearance of the AFAR protein.(ABSTRACT TRUNCATED AT 250 WORDS)

The search for BRCA1

BRCA1, a gene predisposing to breast and ovarian cancer, was mapped to chromosome 17q21 by linkage analysis. Loss of heterozygosity in breast and ovarian tumors from BRCA1-linked patients always involved loss of wild-type alleles from chromosome 17q21, suggesting that BRCA1 acts as a tumor suppressor gene. Meiotic recombination in linked families constrained the BRCA1 region to an estimated physical size of 650 kilobases. Twenty-two candidate genes were isolated by screening complementary DNA libraries with yeast artificial chromosomes and cosmids from the critical region. Of these, 8 were known human genes, 7 were homologues of genes identified in other species, and 7 encoded novel transcripts. Each gene were sequenced and analyzed for variation, revealing 44 variants, including two missense mutations in two genes which segregated with breast cancer and were not found in controls. However, no frame-shift, nonsense, or regulatory mutations were found.

A role for non-NMDA excitatory amino acid receptors in regulating the basal activity of rat globus pallidus neurons and their activation by the subthalamic nucleus

We have investigated the hypothesis that excitatory amino acid (EAA) receptors in the globus pallidus (GP) play a significant role in maintaining the firing rates of GP neurons under basal conditions and following activation of the subthalamic nucleus (STN). Drugs were infused directly into the GP and/or STN while the extracellular single unit activity of Type II GP neurons was recorded in ketamine-anesthetized rats. Local infusions of the EAA agonists NMDA (30-300 pmol/200 nl) or AMPA (0.1-1 pmol/200 nl) elicited increases in the firing rate of GP neurons in a dose-dependent fashion. Infusion of the GABAA receptor antagonist bicuculline methiodide (1-10 pmol/100 nl) into the STN also elicited dose-related increases in the firing rate of GP neurons. Intrapallidal infusion of the non-NMDA (AMPA/kainate) receptor antagonist NBQX (0.1-1.0 nmol) reduced the basal firing rate of GP neurons by 40%. In contrast, the NMDA antagonist MK-801 (0.01-0.1 nmol) produced no significant effect on basal firing rate. Intrapallidal infusion of the non-selective EAA receptor antagonist kynurenic acid or NBQX reversed or blocked the increase in firing rate of GP neurons following bicuculline-induced activation of the STN. Similar treatment with MK-801, however, had no significant effect on this response. These results indicate that tonic stimulation of non-NMDA receptors plays an important role in maintaining the basal activity of GP neurons and in mediating the effects of increased excitatory input from subthalamic afferent neurons.

An update on the cause of abdominal aortic aneurysms

Historically the most common cause of abdominal aortic aneurysms has been attributed to atherosclerotic degeneration of the vessel wall. However, over the last decade this widely accepted theory has been challenged by a substantial body of research that proposes that atherosclerosis is more likely to be an associated finding rather than an instigating factor. Arguments against an atherosclerotic theory are supported by differences in the characteristics of atherosclerotic occlusive disease and aneurysmal disease. Emerging theories propose that development of abdominal aortic aneurysms involves genetic factors and fundamental structural changes in the aorta. The purpose of this article is to review these emerging theories and discuss their implications on patient treatment.

Interdisciplinary team training in geriatrics: reaching out to small and medium-size communities

Since 1989, six teams in the state of Michigan have been involved in a team training program designed to promote the development of geriatric services in small to medium-size communities. The program was enthusiastically received by participants, but after 18 months, only half of the teams had implemented clinical services for older adults. Monitoring the progress of the teams over 18 months and analyzing the activities of two teams revealed that financially stable and supportive sponsoring agencies and the community were critical factors in the implementation of interdisciplinary clinical services in geriatrics. Future team training programs trying to promote the development of geriatric services in small to medium-size communities should try to address these issues through community organization interventions.

The Cell-Sweep. A new cervical cytology sampling device

The Cell-Sweep, a new cervical cytology sampling device, was prospectively evaluated. From September 1, 1992, to October 31, 1992, 548 cervical cytology smears were prepared using the Cell-Sweep. They were compared to 524 cervical smears performed between January 1, 1993, and February 28, 1993, using the Cytobrush and Ayre spatula. One smear in the Cell-Sweep group and nine in the Cytobrush/Ayre spatula group were unsatisfactory for evaluation secondary to drying artifact (P < .01). Seven (1.2%) of the Cell-Sweep smears and 13 (2.4%) of the Cytobrush/Ayre spatula smears were inadequate due to obscuring of the epithelial cells by blood (P = .11). Of the smears obtained with the Cell-Sweep, 66 (12%) contained no endocervical component versus 42 (8%) of the smears obtained with the Cytobrush/Ayre spatula (P = .03). In the Cell-Sweep group there were 130 (23.7%) abnormal smears versus 110 (20.9%) in the Cytobrush/Ayre spatula group (P = .3). However, high grade squamous intraepithelial lesions (SILs) were identified in 10 (1.8%) smears obtained with the Cell-Sweep and in 2 (0.4%) obtained with the Cytobrush/Ayre spatula (P = .02). The Cell-Sweep produced a small proportion of unsatisfactory smears due to drying artifact or blood. Even though the proportion of smears lacking endocervical cells was statistically greater with the Cell-Sweep than with the Cytobrush/Ayre spatula, there was no difference in the rate of detection of atypical squamous cells and low grade SIL. The Cell-Sweep appears to detect an increased number of high grade SILs. This device deserves further study with histopathologic correlation.

Methotrexate in rheumatoid arthritis. A five-year prospective multicenter study

OBJECTIVE

To evaluate the efficacy and tolerability of oral methotrexate (MTX) in rheumatoid arthritis (RA) in a long-term prospective trial.

METHODS

One hundred twenty-three patients with RA who completed a 9-month multicenter randomized trial comparing MTX and auranofin enrolled in this 5-year prospective study of MTX.

RESULTS

Significant (P = 0.0001) improvement compared with baseline was noted in all clinical disease variables, functional status, and the Westergren erythrocyte sedimentation rate (ESR). "Marked improvement" occurred in 87 (71%) and 85 (69%) of the patients, respectively, in the joint pain/tenderness index and the joint swelling index at the last evaluable visit. Forty-four patients (36%) withdrew during the study. Eight (7%) withdrew due to lack of efficacy, and 8 (7%) due to adverse experiences, including 1 patient with cirrhosis. At 5 years, 64% of patients were still taking MTX and completed the study.

CONCLUSION

This large prospective study of long-term MTX treatment demonstrates sustained clinical response and improvement in the Westergren ESR and functional assessment scores, with an acceptable toxicity profile.

Luteal phase hyperprolactinemia

OBJECTIVE

To determine the incidence of both isolated and repetitive prolactin elevations in the luteal phase of otherwise normoprolactinemic women. To see if sporadic luteal-phase hyperprolactinemia is associated with progesterone deficiency, and to explore a possible physiological basis for sporadic hyperprolactinemia by TRH challenge.

SETTING

Hospital-based reproductive endocrinology/infertility service.

DESIGN

Prospective measurement of luteal phase serum progesterone and prolactin in normoprolactinemic ovulatory women. TRH stimulation testing in volunteers with repetitive luteal phase hyperprolactinemia and normoprolactinemic controls.

PATIENTS

133 sequentially selected infertile, ovulatory women with normal prolactin levels in the proliferative phase of the cycle.

INTERVENTIONS

Measurement of serum progesterone and prolactin during the luteal phase, based on the day of the LH surge. TRH testing in the midluteal phase of the cycle in patients with two or more luteal phase prolactin elevations, and in five normoprolactinemic volunteers in both the preovulatory and midluteal phase.

RESULTS

Of 133 subjects, 85 (64%) had no prolactin level exceeding 20 ng/mL in the luteal phase. Thirty-three (25%) had two or more elevated levels, and were considered to have repetitive luteal phase hyperprolactinemia (LPH). TRH testing in control subjects resulted in a greater prolactin response in the preovulatory phase. The group with LPH demonstrated an initial elevation of prolactin greater than that of the normoprolactinemic controls, but a subsequent drop to levels lower than both preovulatory and midluteal normoprolactinemic controls by 45 minutes.

CONCLUSIONS

Sporadic luteal-phase hyperprolactinemia is a relatively common event (36% of 133 subjects in the present series). Of these 48 women, 33 (69%) had repetitive elevations, suggesting the elevation in these subjects to be more than a random event. The physiological validity of this observation is further demonstrated by an abnormal response to TRH stimulation, but the normal levels of luteal phase progesterone leave questions as to its pathological importance.

Seroprevalence of HIV and risk behaviors among young homosexual and bisexual men. The San Francisco/Berkeley Young Men's Survey

OBJECTIVE

To estimate the prevalence of human immunodeficiency virus (HIV) infection and risk behaviors among young homosexual and bisexual men sampled from public venues in San Francisco and Berkeley, Calif.

DESIGN

A survey of 425 young homosexual and bisexual men sampled from 26 locations during 1992 and 1993. Participants were interviewed and blood specimens were drawn and tested for HIV, level of CD4+ T lymphocytes, and markers of hepatitis B and syphilis.

SETTING

Public venues in San Francisco and Berkeley, including street corners and sidewalks, dance clubs, bars, and parks.

POPULATION STUDIED

Homosexual and bisexual men aged 17 to 22 years.

MAIN OUTCOME MEASURES

Prevalence of HIV infection and risk behaviors.

RESULTS

The HIV seroprevalence was 9.4% (95% confidence interval, 6.8% to 12.6%). The prevalence of markers for hepatitis B was 19.8% (95% confidence interval, 16.1% to 23.9%), and that for syphilis was 1.0% (95% confidence interval, 0.3% to 2.4%). The HIV seroprevalence was significantly higher among African Americans (21.2%) than among other racial/ethnic groups (P = .002). Approximately one third (32.7%) of the participants reported unprotected anal intercourse, and 11.8% reported injecting drug use in the previous 6 months. At the time of interview, 70.0% of the HIV-infected men did not know that they were HIV seropositive, and only 22.5% were receiving medical care for HIV infection.

CONCLUSIONS

The prevalence of HIV infection is high among this young population of homosexual and bisexual men, particularly among young African-American men. The high rates of HIV-related risk behaviors suggest a considerable risk for HIV transmission in this population. Prevention programs and health services need to be tailored to address the needs of a new generation of homosexual and bisexual men.

The long isoform of the rat thyrotropin-releasing hormone receptor down-regulates Gq proteins

A cDNA encoding the long isoform of the rat thyrotropin releasing hormone (TRH) receptor was expressed stably in HEK-293 cells. Polymerase chain reaction analysis confirmed expression of mRNA encoding only the long and not the short isoform. Activation of this receptor with TRH caused a large stimulation in production of inositol phosphates but did not produce either activation of basal or inhibition of forskolin-amplified adenylyl cyclase activity. Sustained exposure of these transfected cells to TRH resulted in a substantial reduction in cellular levels of Gq alpha-like immunoreactivity from some 12 to 5 pmol/mg of membrane protein without significant alterations in cellular levels of the alpha subunits of Gs, Gi1, Gi2, Gi3, or Go. Equivalent experiments in GH3 cells also indicated a marked down-regulation of Gq alpha/G11 alpha. Dose-response curves indicated that 20 nM TRH produced half-maximal down-regulation of cellular Gq-like immunoreactivity in the transfected HEK-293 cells and that half-maximal loss was produced within 3-4 h. Separation of the transfected HEK-293 cell membranes in SDS-polyacrylamide gel electrophoresis conditions able to resolve individual members of the Gq family of G-proteins demonstrated the presence of two related G-proteins. Both of the expressed Gq-like G-proteins were observed to be down-regulated in parallel by TRH. The similarity of dose-response curves and time-courses for loss of the two G-proteins indicates that the long isoform of the rat TRH receptor does not functionally select between these two transducer proteins. In GH3 cells both Gq alpha and G11 alpha, which are expressed at similar levels, were observed to be down-regulated equivalently by treatment with TRH.

Prevalence of periodontal pathogens with varying metabolic control of diabetes mellitus

The purpose of this study was to determine the prevalence of 5 periodontal pathogens in individuals with diabetes mellitus. Subjects (n = 107) 20-70 years of age with type 1 (n = 60) or 2 (n = 47) diabetes mellitus were studied for the occurrence of the periodontal pathogens A. actinomycetemcomitans, F. nucleatum, E. corrodens, P. gingivalis and P. intermedia. Subgingival plaque was sampled in each subject from a single site exhibiting the greatest inflammation. The evaluation of selected periodontal bacterial pathogens was based on an immunoassay utilizing bacterial specific monoclonal antibodies. 35% of the sites harbored P. gingivalis, 28% F. nucleatum and 21% E. corrodens. A. actinomycetemcomitans and P. intermedia were found in less than 10% of the sites. Subjects for whom the probing depth at the sampled site was > or = 4 mm were more often found to have detectable pathogens than those with a probing depth < or = 3 mm. Diabetic factors such as duration, type and metabolic control of the disease had no statistically significant effect on the prevalence of these bacteria.

Measurement of the attenuation coefficient for Livermore Thoracic Phantom lungs fabricated using contemporary materials

The University of Cincinnati has reproduced the original formulation for the Livermore Thoracic Phantom lungs using contemporary materials and has adopted the linear attenuation coefficient as the primary quality assurance parameter for evaluating the performance capabilities of these new lung phantoms. The Livermore Thoracic Phantom was originally fabricated in 1978 to intercalibrate detector systems used to measure plutonium and other low-energy, photon emitting radionuclides deposited in the respiratory tract. The linear attenuation coefficient is a critical performance indicator for these phantom lungs since the presence of any material with a high effective atomic number (where Z > or = 20) will make a significant change in the photoelectric cross section, the predominant mode of interaction for plutonium x rays. A set of test lungs was fabricated with KCl to introduce a known quantity of 40K in the phantom and to determine, by measurement and calculations, what change would be made to the attenuation coefficient at photon energies below 100 keV as a result of the modified formulation. The KCl increased the linear attenuation coefficient below 60 keV by more than a factor of two, which would produce a substantial systematic error in any subsequent calibration measurements performed with these modified phantom lungs. These results support use of the attenuation coefficient as an important performance indicator for the Livermore Thoracic Phantom lungs and also suggest that KCl not be added to the lung tissue substitute formulation as a means to incorporate 40K in the phantom for low energy calibrations.

Clinical stage 1 non-Hodgkin's lymphoma: long-term follow-up of patients treated by the British National Lymphoma Investigation with radiotherapy alone as initial therapy

A retrospective analysis was performed of 451 adult patients with clinical stage 1/1E non-Hodgkin's lymphoma treated initially with radiotherapy alone. Histopathologically 208 patients had low-grade disease and 243 patients high-grade disease. The complete remission (CR) rate was higher in patients with low-grade disease (98%) than in those with high-grade disease (84%) (P < 0.0001). The relapse rate was similar in both histological categories, and relapse usually occurred within 5 years. The resulting overall actuarial percentage of patients achieving CR and remaining disease free (at 10 years) was 47% in patients with low-grade disease and 45% for those with high-grade disease. Salvage therapy was frequently successful in younger patients, and the overall cause-specific survival at 10 years was 71% for low-grade disease and 67% for high-grade disease. In those patients under 60 years of age at diagnosis, the overall cause-specific survival at 10 years was 84% and 80% for those with low-grade and high-grade disease respectively. These long-term results in young patients with clinical stage 1 disease are encouraging, and it will be difficult to demonstrate improved survival with initial chemotherapy either with or without radiotherapy, until new prognostic factors are found to identify poor-risk patients.