N-Methyl-D-aspartate receptor blockade induces neuronal apoptosis in cortical culture

Whereas excessive activation of the NMDA receptor may contribute to ischemic neuronal injury, physiologic activation may promote neuronal survival under certain conditions. Consistently, it has recently been shown that NMDA antagonists induce apoptosis of central neurons in immature rats. In the present study, we have examined whether NMDA antagonists induce neuronal apoptosis also in a culture condition. Exposure of cortical cultures (DIV 10-13) to MK-801 (1-10 microM) for 48 h resulted in death of about 30-40% of neurons. Similar neuronal death was induced by exposure to other NMDA antagonists, D-AP5 and dextromethorphan. The neuronal death was dependent on the culture age; MK-801 induced much less neuronal death in younger (DIV 7) and older (DIV 16-19) cultures. The NMDA antagonist-induced neuronal death was accompanied by cell body shrinkage, nuclear fragmentation, and cleavage/activation of caspase-3. Furthermore, it was attenuated by cycloheximide and zVAD-fmk, indicating that the death occurred mainly by the apoptosis mechanism. As in several other apoptosis models, high-potassium medium blocked the NMDA antagonist-induced apoptosis, which was reversed by voltage-gated calcium channel blockers. The present results demonstrate that NMDA antagonists induce neuronal apoptosis in cortical culture, consistent with the findings obtained in immature rats. Since the activation of the voltage-gated calcium channels attenuated the NMDA antagonist-induced apoptosis, it may be another example of the "calcium set point hypothesis."

The value of patient-reported adherence to antiretroviral therapy in predicting virologic and immunologic response. California Collaborative Treatment Group

OBJECTIVE

To correlate self-reported antiretroviral adherence with virologic suppression.

DESIGN

Prospective observational study of adherence to therapy nested in a randomized comparative trial of frequent versus infrequent monitoring of plasma HIV RNA.

SETTING

Five university-affiliated HIV clinics.

PATIENTS

A group of 173 HIV-infected patients with a mean baseline CD4 count of 142 x 10(6) cells/l (range 3-515) of whom 164 and 119 completed adherence questionnaires at 2 and 6 months, respectively.

INTERVENTION

Individualized, unrestricted antiretroviral therapy.

MEASUREMENTS

Patients were classified into four groups by adherence to therapy in the previous 4 weeks (< 80%, 80-95%, 95-99%, 100%). Plasma HIV RNA levels and CD4 lymphocyte counts were measured bimonthly.

RESULTS

Recreational drug or alcohol use was associated with decreased adherence, whereas frequency of HIV RNA monitoring, demographic variables, (age, gender, education, and risk group) and stage of disease had no effect. Greater HIV suppression at 6 months was seen across four categories of increasing adherence (P = 0.009 for linear trend). Patients reporting < 80% adherence at 6 months had a 0.2 log10 copies/ml increase in HIV RNA and a loss of 19 x 10(6) CD4 cells/l compared with a 1.1 log10 copies/ml decrease in HIV RNA and an increase of 72 x 10(6) CD4 cells/l in those reporting 100% adherence (P = 0.02).

CONCLUSION

Self-reported poor adherence (< 80%) and drug or alcohol use predicted non-response of HIV RNA at 6 months of antiretroviral therapy.

IKK1-deficient mice exhibit abnormal development of skin and skeleton

IkappaB kinases (IKKs) IKK1 and IKK2 are two putative IkappaBalpha kinases involved in NF-kappaB activation. To examine the in vivo functions of IKK1, we generated IKK1-deficient mice. The mutant mice are perinatally lethal and exhibit a wide range of developmental defects. Newborn mutant mice have shiny, taut, and sticky skin without whiskers. Histological analysis shows thicker epidermis, which is unable to differentiate. Limbs and tail are wrapped inside the skin and do not extend properly out of the body trunk. Skeleton staining reveals a cleft secondary palate, split sternebra 6, and deformed incisors. NF-kappaB activation mediated by TNFalpha and IL-1 is diminished in IKK1-deficient mouse embryonic fibroblast (MEF) cells. The IKK complex in the absence of IKK1 is capable of phosphorylating IkappaBalpha and IkappaBbeta in vitro. Our results support a role for IKK1 in NF-kappaB activation and uncover its involvement in skin and skeleton development. We conclude further that the two related kinases IKK1 and IKK2 have distinct functions and can not be substituted for each other's functions.

Antioxidative and proapoptotic effects of riluzole on cultured cortical neurons

Riluzole is used clinically in patients with amyotrophic lateral sclerosis. As oxidative stress, in addition to excitotoxicity, may be a major mechanism of motoneuron degeneration in patients with amyotrophic lateral sclerosis, we examined whether riluzole protects against nonexcitotoxic oxidative injury. Probably reflecting its weak antiexcitotoxic effects, riluzole (1-30 microM) attenuated submaximal neuronal death induced by 24-h exposure to 30 microM kainate or NMDA, but not that by 100 microM NMDA, in cortical cultures. Riluzole also attenuated nonexcitotoxic oxidative injury induced by exposure to FeCl3 in the presence of MK-801 and CNQX. Consistent with its antioxidative effects, riluzole reduced Fe3+-induced lipid peroxidation, and inhibited cytosolic phospholipase A2. By contrast, riluzole did not attenuate neuronal apoptosis induced by staurosporine. Rather unexpectedly, 24-48-h exposure to 100-300 microM riluzole induced neuronal death accompanied by nuclear and DNA fragmentations, which was attenuated by caspase inhibitor carbobenzyloxy-Val-Ala-Asp-fluoromethyl ketone but not by protein synthesis inhibitor cycloheximide. The present study demonstrates that riluzole has direct antioxidative actions, perhaps in part by inhibiting phospholipase A2. However, in the same neurons, riluzole paradoxically induces neuronal apoptosis in a caspase-sensitive manner. Considering current clinical use of riluzole, further studies are warranted to investigate its potential cytolethal effects.

A case of hypohidrotic ectodermal dysplasia

Hypohidrotic ectodermal dysplasia (HED) is a rare, hereditary, congenital disease that affects several ectodermal structures. It is characterised by the following: anhidrosis or hypohidrosis, dental abnormalities, hypotrichosis, and a characteristic facies. The face shows prominent frontal bosses, supraorbital ridges and depressed bridges. We experienced a case of hypohidrotic ectodermal dysplasia in a 43-year-old male who had four characteristic features. A skin biopsy from the palm showed a total absence of the eccrine glands. The diagnosis was made on the basis of clinical features and skin biopsy findings.

The effect of six months treatment with a 100 mg daily dose of dehydroepiandrosterone (DHEA) on circulating sex steroids, body composition and muscle strength in age-advanced men and women

OBJECTIVE

The biological role of the adrenal sex steroid precursors--DHEA and DHEA sulphate (DS) and their decline with ageing remains undefined. We observed previously that administration of a 50 daily dose of DHEA for 3 months to age-advanced men and women resulted in an elevation (10%) of serum levels of insulin-like growth factor-I (IGF-I) accompanied by improvement of self-reported physical and psychological well-being. These findings led us to assess the effect of a larger dose (100 mg) of DHEA for a longer duration (6 months) on circulating sex steroids, body composition (DEXA) and muscle strength (MedX).

SUBJECTS AND DESIGN

Healthy non-obese age-advanced (50-65 yrs of age) men (n = 9) and women (n = 10) were randomized into a double-blind placebo-controlled cross-over trial. Sixteen subjects completed the one-year study of six months of placebo and six months of 100 mg oral DHEA daily.

MEASUREMENTS

Fasting early morning blood samples were obtained. Serum DHEA, DS, sex steroids, IGF-I, IGFBP-1, IGFBP-3, growth hormone binding protein (GHBP) levels and lipid profiles as well as body composition (by DEXA) and muscle strength (by MedX testing) were measured at baseline and after each treatment.

RESULTS

Basal serum levels of DHEA, DS, androsternedione (A), testosterone (T) and dihydrotestosterone (DHT) were at or below the lower range of young adult levels. In both sexes, a 100 mg daily dose of DHEA restored serum DHEA levels to those of young adults and serum DS to levels at or slightly above the young adult range. Serum cortisol levels were unaltered, consequently the DS/cortisol ratio was increased to pubertal (10:1) levels. In women, but not in men, serum A, T and DHT were increased to levels above gender-specific young adult ranges. Basal SHBG levels were in the normal range for men and elevated in women, of whom 7 of 8 were on oestrogen replacement therapy. While on DHEA, serum SHBG levels declined with a greater (P < 0.02) response in women (-40 +/- 8%; P = 0.002) than in men (-5 +/- 4%; P = 0.02). Relative to baseline, DHEA administration resulted in an elevation of serum IGF-I levels in men (16 +/- 6%, P = 0.04) and in women (31 +/- 12%, P = 0.02). Serum levels of IGFBP-1 and IGFBP-3 were unaltered but GHBP levels declined in women (28 +/- 6%; P = 0.02) not in men. In men, but not in women, fat body mass decreased 1.0 +/- 0.4 kg (6.1 +/- 2.6%, P = 0.02) and knee muscle strength 15.0 +/- 3.3% (P = 0.02) as well as lumbar back strength 13.9 +/- 5.4% (P = 0.01) increased. In women, but not in men, an increase in total body mass of 1.4 +/- 0.4 kg (2.1 +/- 0.7%; P = 0.02) was noted. Neither gender had changes in basal metabolic rate, bone mineral density, urinary pyridinoline cross-links, fasting insulin, glucose, cortisol levels or lipid profiles. No significant adverse effects were observed.

CONCLUSIONS

A daily oral 100 mg dose of DHEA for 6 months resulted in elevation of circulating DHEA and DS concentrations and the DS/cortisol ratio. Biotransformation to potent androgens near and slightly above the range of their younger counterparts occurred in women with no detectable change in men. Given this hormonal milieu, an increase in serum IGF-I levels was observed in both genders but dimorphic responses were evident in fat body mass and muscle strength in favour of men. These differences in response to DHEA administration may reflect a gender specific response to DHEA and/or the presence of confounding factor(s) in women such as oestrogen replacement therapy.

The activity of the scs and scs' insulator elements is not dependent on chromosomal context

Sequence elements that protect a reporter gene from chromosomal position effects or that block enhancer-activated transcription are called insulators. Using a plasmid-based microinjection assay with Xenopus laevis oocytes, we show that the heterologous Drosophila melanogaster scs and scs' insulator elements do not require chromosomal context to block enhancer-activated transcription. A single insulator element partially blocks enhancer-activated transcription, indicating that each element operates independently rather than as part of a pair. Deletion analysis of the 1.8-kb scs element identified a 220-bp fragment from one of the DNase I-hypersensitive regions that has full blocking activity in the oocyte assay. This fragment corresponds to the critical region of the scs mapped in previous studies with Drosophila. A time course of transcription shows that the scs blocks enhancer-activated transcription as early as transcription can be detected, about 30 min after injection. Complete assembly of the DNA template into nucleosomes requires 4 h. The scs and scs' sequences do not block site-specific recombination by FLP recombinase, implying that insulators do not operate by a general mechanism that physically sequesters the DNA. These data are most consistent with a model for insulator action in which direct interaction between the insulator and either the enhancer or promoter confers directionality to enhancer-activated transcription.

Serum thyrotropin-binding inhibiting immunoglobulin and thyroperoxidase antibody in Graves' hyperthyroidism after 131I therapy

Seventeen patients who received radioiodine (131I) therapy for Graves' hyperthyroidism had serial blood samples taken before therapy and after therapy for a period of at least 1 year. At 1 year post-therapy, six patients were hypothyroid. Seven patients were euthyroid, and four patients were hyperthyroid. Prior to isotope administration, 14 patients had detectable serum thyrotropin-binding inhibiting immunoglobulin (TBII) and 16 patients had detectable serum thyroperoxidase antibody (TPOAb). Three to 6 months after therapy, 11 of 14 TBII-positive patients demonstrated a marked increase (> 10%) in serum TBII activity. Four patients out of 11 developed hypothyroidism and six of the 11 developed euthyroidism. A decrease in TBII was observed in three patients who developed hyperthyroidism. In the three patients with undetectable TBII prior to therapy, two had high titers of TPOAb. Seven patients demonstrated a marked increase in TPOAb 3 to 6 months after therapy. Of these, four developed hypothyroidism and three developed euthyroidism, whereas three of the four patients who had a marked decrease in TPOAb developed hyperthyroidism. This study demonstrated that an increase in serum TBII and TPOAb activity 3 to 6 months after 131I therapy, may be useful in predicting which patients may develop euthyroidism or hypothyroidism after 1 year of 131I therapy.

The dietary requirement of juvenile grass shrimp (Penaeus monodon) for vitamin D

Two 8-wk experiments were conducted to determine the adequate level of dietary vitamin D for juvenile grass shrimp (Penaeus monodon). In Experiment 1, purified diets with six levels (0, 0.1, 0.5, 2.5, 12.5 and 62.5 mg/kg diet) of supplemental ergocalciferol and cholecalciferol were fed to P. monodon (mean weight 0.19 +/- 0.02 g). In Experiment 2, we used 0, 0.05, 0.1, 0.2, 0.3, 0.6 and 1.0 mg/kg of supplemental cholecalciferol in basal diet fed to the shrimp (mean weight 0.25 +/- 0.03 g). In both experiments, shrimp fed vitamin D-deficient diets grew poorly. In Experiment 1, poorer growth performance was observed in shrimp fed diets containing ergocalciferol compared with those fed the diets containing cholecalciferol. In Experiment 2, weight gain was highest in shrimp fed the diet supplemented with 0.2 mg cholecalciferol/kg diet, followed by the groups fed 0.1 mg/kg, then 0.3 mg/kg, 0.05 and 0.6 mg/kg, 1.0 mg/kg, and finally the unsupplemented control group. The differences among these groups were significant (P < 0.05). The feed efficiency ratio and alkaline phosphatase activity generally followed the same pattern as the weight gain. Analysis by brokenline regression of weight gain and alkaline phosphatase activity of the shrimp in Experiment 2 indicated that the adequate dietary cholecalciferol concentration for growing P. monodon is approximately 0.1 mg/kg.

Hormonal change in an adult with Prader-Willi syndrome: report of a case

We report a classical case of Prader-Willi syndrome (PWS) in an adult with typical interstitial deletion of chromosome 15, and emphasize the study of hormonal change. This 21-year-old female had PWS face characteristics, small hands and feet, marked obesity, mental retardation, growth retardation, absence of puberty and amenorrhea. She also had the characteristic history of infantile hypotonia, poor feeding, failure to thrive and then improved appetite, followed by obesity from the age of four years. She had compulsive hyperphagia, to the extent of stealing and lying to take food. Chromosome study with high resolution banding technique revealed a small interstitial deletion at band q12 of chromosome 15, which is characteristically found in a majority of patients with PWS. Hormonal study revealed hypogonadism and growth hormone deficiency of supposed hypothalamic origin. She also had non-insulin-dependent diabetes mellitus with decreased pancreatic insulin reserve.

Tamoxifen stimulates human papillomavirus type 16 gene expression and cell proliferation in a cervical cancer cell line

The widely adopted use of tamoxifen as a chemotherapeutic agent is primarily based on its inhibition of cancer cell growth. However, we report that tamoxifen at low concentrations (10(-9) and 10(-11) M) causes stimulation of cell proliferation in a cervical cancer cell line, SFR. The facts that SFR cells do not contain estrogen receptors and are estrogen nonresponsive imply the existence of an antiestrogen-specific binding protein and suggest that the effect of tamoxifen is possibly mediated through a pathway other than estrogen receptors. Tamoxifen at low concentrations stimulated human papillomavirus type 16 (HPV-16) gene transcription and E7 protein production. Levels of HPV-16 mRNA and E7 protein reached a peak at approximately 2-4 h after tamoxifen treatment, persisted for several hours, and subsequently decreased to their prestimulation levels by about 24 h after treatment. Our results indicate for the first time that tamoxifen stimulates cell proliferation of cervical cancer cells, and we suggest that the enhanced HPV-16 mRNA and E7 protein levels are probably responsible.

[Relationship between thyroid echogram and thyroid function in Hashimoto's thyroiditis]

Seventeen cases of untreated Hashimoto's thyroiditis were selected from the files of the Taipei Municipal Jen-Ai Hospital during the period from Jan. 1985 to Jan. 1986. All the cases were confirmed by a physical examination, determination of thyroid antibodies and fine needle aspiration cytology. Thyroid function was also determined. According to the echogenicity of the thyroid, they were divided into 2 groups, group A (8 cases) and group B (9 cases). In group A, homogeneous hypoechogenicity of the thyroid was noted and was lower than that of the adjacent muscles. In group B, heterogeneous echogenicity of the thyroid with equal or higher echogenicity than that of the adjacent muscles was noted. Group A showed a significantly lower serum T4, T3 and a higher serum TSH in comparison with group B. Five cases in group A presented hypothyroidism clinically while only 1 in group B presented. In conclusion, in the cases of Hashimoto's thyroiditis, the homogeneous hypoechogenicity of the thyroid echogram suggested the possibility of hypothyroidism. Statistically, the sensitivity was 83.3%, specificity 72.8%, positive prediction value 62.5% and the negative prediction value was 88.9%.

Apolipoproteins A-I and B in non-insulin-dependent diabetes mellitus

In recent years apolipoproteins A-I and B examinations have been performed on patients with coronary artery disease as a better predictor of the severity of atherosclerosis. In the present study, 21 treated male and 22 treated female patients with non-insulin-dependent diabetes mellitus (NIDDM) were examined and compared with controls of the same sex, age and body mass (23 males, 21 females). Cholesterol, triglyceride, LDL-cholesterol in male and female patients with NIDDM were significantly higher than in male and female controls. HDL-cholesterol in male and female patients with NIDDM was not different from those of male and female controls. Apolipoproteins A-I and B in male and female patients with NIDDM were higher than in male and female controls. [Apolipoproteins A-I (g/L) male 1.40 +/- 0.21 vs 1.25 +/- 0.15, p less than 0.005; female 1.56 +/- 0.23 vs 1.42 +/- 0.24, p less than 0.025. Apolipoproteins B (g/L) male 1.29 +/- 0.30 vs 0.97 +/- 0.22, p less than 0.001; female 1.34 +/- 0.34 vs 0.98 +/- 0.35, p less than 0.001.] Discrepancy between the higher apolipoprotein A-I and the normal HDL-cholesterol in in NIDDM supports the theory of altered composition of HDL particles in diabetic patients. The controversy between the higher apolipoprotein A-I and the higher incidence of atherosclerosis in patients with NIDDM makes the clinical usefulness of this laboratory measurement doubtful in these patients.

An experimental comparison of four hearing aid prescription methods

Four hearing aid prescription methods were compared. A digital master hearing aid was used to produce the prescribed frequency gain characteristics. Measures of speech recognition and paired comparison judgments of relative speech intelligibility and speech quality were obtained at three output levels for each of the experimental frequency gain characteristics. No single prescriptive method emerged as being clearly superior. Relative performance of the four prescriptive methods varied as a function of output level. Similar results were observed for both speech recognition testing and paired comparison testing.

Nasal absorption of nafarelin acetate, the decapeptide [D-Nal(2)6)]LHRH, in rhesus monkeys. I

Nafarelin acetate, [D-Nal(2)6]LHRH, a highly potent superagonist of luteinizing hormone-releasing hormone, was given intranasally to six female rhesus monkeys. Absorption was rapid and very reproducible, with peak levels occurring at 15-30 min and a bioavailability of approximately 2% relative to a subcutaneous dose. The nasal dose response was highly nonlinear. The nonlinearity was apparently associated with the absorption phase, since elimination profiles at all doses were similar.

Transcription-termination factor Rho from Bacills subtilis

A protein has been isolated from Bacillus subtilis which has functions similar to that of transcription termination factor rho (rho) from Escherichia coli. The apparent molecular weight of the B. subtilis rho factor is about 80000-95000 as estimated by a non-denaturing polyacrylamide gel electrophoresis method. It contains two subunits with a molecular weight of 47000 as determined by sodium dodecylsulfate/polyacrylamide gel electrophoresis. The rho factor shows poly(C)-dependent beta-gamma ATPase activity and depresses the activity of RNA synthesis from B. subtilis phage rho 29 DNA template with purified B. subtilis RNA polymerase holoenzyme. The specific activity of the poly(C)-dependent ATPase of the B. subtilis rho factor was significantly less than that of the E. coli rho factor. In the presence of rho factor fewer RNA transcripts were produced overall from the rho 29 template and smaller RNA transcripts with discrete sizes were made. These results suggest that the B. subtilis rho factor can catalyze transcription termination at specific sites on rho 29 phage DNA in vitro.