Biomedical subjects

Jose Martinez

Publications and source records attributed to Jose Martinez.

4 recordsLinked to original sources

PubMed2005

Doxapram-induced panic attacks and cortisol elevation.

Numerous agents with differing biological properties and central nervous system (CNS) effects can induce panic attacks in predisposed individuals. A potential explanation of this finding is that panic disorder patients are more likely to panic than normal control subjects when given a panicogen due to an excessive fear response to somatic arousal. We test this hypothesis by using doxapram, a panicogen with minimal CNS effects, to induce panic in patients and control subjects. Doxapram was given to six subjects with panic disorder with or without agoraphobia and four healthy volunteers. Measures comprised the Acute Panic Inventory, the Borg Exertion scale, the 10-point Anxiety Scale, the 10-point Apprehension Scale, cortisol, prolactin, and MHPG, all obtained at baseline and multiple time points after the doxapram infusion. All panic disorder patients panicked with doxapram, whereas no control subjects had a panic attack. Panic patients had similar levels of breathlessness with doxapram compared with control subjects. Although panic patients had higher levels of anxiety and apprehension, these did not change significantly with doxapram compared with control levels. Doxapram led to similar increases in cortisol and prolactin in both groups, and MHPG was consistently elevated in panic patients, but unaffected by doxapram. These results show that doxapram is a useful panicogen in the study of panic disorder. Since the panic patients and control subjects had similar levels of physiological and psychological arousal, but the panic patients were more likely to have a panic attack, this lends support to the concept of a sensitized fear network in panic disorder patients.

Adult↗

PubMed2005

Subannular ventilation tubes: retrospective study.

OBJECTIVE: To evaluate the efficiency of a subannular tube insertion technique in a group of pediatric patients with adhesive otitis or severe atelectasis of the tympanic membrane. DESIGN: Retrospective nonrandomized case series. SETTING: Tertiary referral centre. MAIN OUTCOME MEASURES: The main outcomes of this study are tube duration according to the type of tube used, the complication rate, and the audiometric gain associated with this procedure. RESULTS: The study group consisted of 190 patients (316 tubes) aged between 3 and 19 years (average 9 years old) and operated on between 1993 and 1999 by four pediatric otolaryngologists. The average follow-up was 53 months. The tubes remained in place for an average of 21.8 months, with fluoroplastic tubes lasting 17.8 months and Goode T tubes lasting 23.8 months. When used in children between 5 and 9 years of age and in cases of adhesive otitis, Goode T tubes showed statistically significantly better results than fluoroplastic tubes. The complications of this technique were otorrhea (17.7%), perforation (7.9%), a plugged tube (7.0%), and cholesteatoma (1.6%). The 5- to 9-year-old group and the reintervention group of patients showed statistically higher complication rates compared with all other groups. Sixty-four patients (128 tubes) were eligible for audiogram analysis, which showed a gain of 13.4 dB (speech reception threshold). CONCLUSIONS: The technique of subannular tube insertion is a safe and effective method for long-term middle ear ventilation in cases of adhesive otitis or severely atelectatic tympanic membrane or for patients with pathology related to dysfunction of the eustachian tube. It offers an alternative to repeated short-term tube insertions for otitis media with effusion or recurrent acute otitis media.

Adolescent↗

PubMed2004

The effect of successful treatment on the emotional and physiological response to carbon dioxide inhalation in patients with panic disorder.

BACKGROUND: A number of studies have shown that patients with panic disorder are more likely to have panic attacks during carbon dioxide inhalation than are normal comparison subjects. Some studies have shown that antipanic medications can reduce the anxiogenic response to carbon dioxide, but none have shown if this is the case for cognitive behavioral therapy or if successful treatment reduces the respiratory physiologic response to carbon dioxide. METHODS: Twenty-five patients with panic disorder and 13 normal comparison subjects underwent baseline testing with 5% and 7% carbon dioxide inhalation. The patients were then retested after at least 12 weeks of treatment with either antipanic medication or cognitive behavioral therapy. Comparison subjects were retested after a similar interval. RESULTS: Successful treatment resulted in lower panic rates, and reduced anxiogenic response. Treatment had no effect, however, on the respiratory physiologic response. CONCLUSIONS: There is dissociation in treatment response between the subjective and objective responses to carbon dioxide inhalation in panic disorder patients, with the former but not the latter showing positive change. We hypothesize that the strengthening of higher cortical control over subcortical fear-related structures, whether via medication or cognitive behavioral therapy treatment, results in less anxiety and fear in response to provoked symptoms reminiscent of naturally occurring panic.

Administration, Inhalation↗

PubMed2002

An octapeptide in the juxtamembrane domain of VE-cadherin is important for p120ctn binding and cell proliferation.

The cadherins are a family of adhesive proteins involved in cell-cell homophilic interactions. VE-cadherin, expressed in endothelial cells, is involved in morphogenesis, regulation of permeability, and cellular proliferation. The cytoplasmic tails of cadherins contain two major domains, the juxtamembrane domain that plays a role in the intercellular localization of the protein and also serves for binding of p120ctn, and a C-terminal domain that associates with beta- or gamma-catenin. A highly conserved region present in the juxtamembrane domain of the cadherins has been shown to be necessary for p120ctn binding in E-cadherin. Using a mutant VE-cadherin lacking a highly conserved octapeptide, we demonstrated that it is required for p120ctn binding to VE-cadherin as determined by immunoprecipitation and colocalization studies. By immunofluorescence, this mutant protein has a topographical distribution similar to that of the wild-type VE-cadherin and, therefore, we conclude that the topographical distribution of VE-cadherin is independent of this motif. In addition, although cell-cell association is present in cells expressing this mutant form of VE-cadherin, we found that the strength of adhesion is decreased. Finally, our results for the first time demonstrate that the interaction of VE-cadherin with p120 catenin plays an important role in cellular growth, suggesting that the binding of p120 catenin to cadherins may regulate cell proliferation.

Amino Acid Sequence↗