Detection of neural signals with vertically grown single platinum nanowire-nanobud.

We developed a nanoscale neural probing device for in vitro sensing of neural activity. Single vertical platinum (Pt) nanowires were fabricated on a microelectrode array by focused ion beam (FIB)-chemical vapor deposition (CVD) in order to improve the spatial resolution of recording and to minimize damage to the cells. Rat neuroblasts were cultured on the electrode array. Electrodes in contact with cells detected prominent spontaneous electrical activity. Our experiments demonstrate the nanoprobes for the real-time detection of electrophysiological signals in neuronal cells.

Long forms of the dopamine receptor (DRD4) gene VNTR are more prevalent in substance abusers: no interaction with functional alleles of the catechol-o-methyltransferase (COMT) gene.

Substance abuse is a complex behavior that is caused by both environmental and genetic factors. Work to understand the genetic factors has focused on genes related to dopamine activity because of its critical role in rewarding and reinforcing behaviors. The DRD3 and other dopamine receptor subtypes are expressed in many areas of the limbic system, and have been the objects of study for their possible roles in several neuropsychiatric disorders. Interest in variants of the D4 gene was heightened by reports that some alleles were more frequent in individuals who score high on Novelty Seeking, an aspect of personality that may be related to drug seeking behavior. We now show that the long form of the DRD4 gene is more frequent in individuals with high quantity/frequency of drug use compared to controls (chi(2) = 5.7, df = 1, P = 0.017, odds ratio = 1.89, CI = 1.1-3.2). There is no difference in DRD3 allele frequencies in these samples, and there is no interaction of DRD4 alleles with those of the catecholamine-o-methyl- transferase gene (COMT) that we previously identified to be more frequent in substance abusers than controls [Vandenbergh, et al.: 1997: Am. J. Med. Gen. 74:439-442].

Body dysmorphic disorder in patients with anxiety disorders and major depression: a comorbidity study.

OBJECTIVE: The authors evaluated the frequency of body dysmorphic disorder in patients with a primary diagnosis of anxiety disorders and major depression. METHOD: Patients with social phobia (N = 54), obsessive-compulsive disorder (N = 53), generalized anxiety disorder (N = 32), panic disorder (N = 47), and major depression (N = 42) and normal comparison subjects (N = 33) were studied. RESULTS: Body dysmorphic disorder was most common in patients with social phobia (11%) and obsessive-compulsive disorder (8%); it was less prevalent among patients with panic disorder (2%), generalized anxiety disorder (0%), and major depression (0%) and among normal subjects (0%). CONCLUSIONS: These findings suggest that body dysmorphic disorder may share etiologic elements with social phobia and obsessive-compulsive disorder.

The frequency of a common anti-DNA antibody idiotype (16/6) in different populations of patients with systemic lupus erythematosus.

The 16/6 anti-DNA idiotype (id) is a pathogenic idiotype first identified on a human hybridoma antibody derived from a patient with systemic lupus erythematosus (SLE). The SA-1 anti-DNA, which antibody was established in a similar fashion from a patient with polymyositis, also carries the 16/6 id, although it has a greater reactivity with dsDNA. The presence of the 16/6 id as defined by anti-16/6 and anti-SA-1 was determined in 3 distinct populations of patients with SLE: 502 Mexicans, 98 English (including Caucasians, West Indians, Chinese, Asians) and 93 Israelis. A similar prevalence (around 20%) of the 2 idiotypes was found, with a significant overlap. The latter finding was supported by a significant correlation noted between the prevalence of the 2 idiotypes (r = 0.58 p less than 0.001). Despite the fact that 16/6 antibody is most probably encoded by a germline gene, thus being genetically determined, no distinction in the prevalence of the ids could be detected between completely different populations of patients with SLE. This finding may support the independent pathogenic role ascribed to the 16/6 id.

Quemadura esofásica por cáusticos / Caustic burning of esophagics

Se revisaron 48 pacientes con diagnóstico de quemadura esofágica por cáuticos. De éstos, 21 fueron hombres y 27 mujeres. La causa principal fue accidente en lactantes y preescolares, suicidio en adolescentes femeninas y accidentes bajo efecto del alcohol en hombres adultos. El agente principal la sosa cáustica. La estenosis fue la complicación principal que requirió dilatación en 40 pacientes con resultados buenos sólo en la tercera parte de los casos. Se realizaron l3 trasposiciones de colon: seis con colon derecho, y seis con colon izquierdo y con un transverso. La evolución fue buena en seis pacientes con trasposición izquierda; buena en cinco pacientes con trasposición derecha; sin embargo, ocurrieron una muerte y una estenosis. El único paciente en que se realizó transposición transversa desarrolló estenosis .

Gonadotropin dynamics in XX males.

Hypothalamic-pituitary gonadotropin function was evaluated in two postpubertal XX males. Serum levels of LH and FSH were moderately elevated, and the serum testosterone level was low. A subnormal response by testicular Leydig cells to hCG was observed. The LH and FSH responses to LRH were normal. A significant LH increase was observed after castration. Weekly administration of testosterone enanthate (250 mg) for 10 consecutive weeks caused a reduction (greater than 75%) in gonadotropins and abolishment of the LRH pituitary response. No differences were observed in terms of gonadotropin dynamics compared with other forms of hypergonadotropic hypogonadism. These results indicate that XX males exhibit hypergonadotropic hypogonadism secondary to testicular failure with a preserved androgen responsiveness of the hypothalamic-pituitary unit.

Induction of ovulation in a true hermaphrodite with male phenotype.

Ovulation was induced in a 16-yr-old 46 XX/47 XXY true hermaphrodite with a male phenotype. The presence of testicular tissue was assessed by a normal androgen response to hCG. Administration of FSH and LH for 8 consecutive days, followed by a single dose of hCG, induced a biphasic serum profile of 17 beta-estradiol and progesterone similar to that observed in normal menstrual cycles. In addition, a significant rise in serum testosterone was noticed during the luteal phase. Laparotomy revealed the presence of a uterus, with evidence of endometrial bleeding and absence of a vagina. These results demonstrated that gonadotropins were able to induce follicular maturation, ovulation, and endometrial bleeding in a true hermaphrodite resembling a normal ovulatory cycle. Gonadotropin administration can be used as a diagnostic tool for establishing the presence of ovarian tissue in this gonadal development abnormality.