Biomedical subjects

Sabine Wilhelm

Publications and source records attributed to Sabine Wilhelm.

30 records · Page 2Linked to original sources

PubMed2002

Immunolocalization of potassium-chloride cotransporter polypeptides in rat exocrine glands.

Potassium-chloride cotransporters (KCCs) encoded by at least four homologous genes are believed to contribute to cell volume regulation and transepithelial ion transport. We have studied KCC polypeptide expression and immunolocalization of KCCs in rat salivary glands and pancreas. Immunoblot analysis of submandibular, parotid, and pancreas plasma membrane fractions with immunospecific antibodies raised against mouse KCC1 revealed protein bands at ca 135 kDa and ca 150 kDa. Immunocytochemical analysis of fixed salivary and pancreas tissue revealed basolateral KCC1 distribution in rat parotid and pancreatic acinar cells, as well as in parotid, submandibular, and pancreatic duct cells. KCC1 or the polypeptide product(s) of one or more additional KCC genes was also expressed in the basolateral membranes of submandibular acinar cells. Both immunoblot and immunofluorescence signals were abolished in the presence of the peptide antigen. These results establish the presence in rat exocrine glands of KCC1 and likely other KCC polypeptides, and suggest a contribution of KCC polypeptides to transepithelial Cl(-) transport.

Animals↗

PubMed2002

Cation channel regulation by COOH-terminal cytoplasmic tail of polycystin-1: mutational and functional analysis.

Polycystin-1 (PKD1) mutations account for approximately 85% of autosomal dominant polycystic kidney disease (ADPKD). We have shown previously that oocyte surface expression of a transmembrane fusion protein encoding part of the cytoplasmic COOH terminus of PKD1 increases activity of a Ca2+-permeable cation channel. We show here that human ADPKD mutations incorporated into this fusion protein attenuated or abolished encoded cation currents. Point mutations and truncations showed that cation current expression requires integrity of a region encompassing the putative coiled coil domain of the PKD1 cytoplasmic tail. Whereas these loss-of-function mutants did not exhibit dominant negative phenotypes, coexpression of a fusion protein expressing the interacting COOH-terminal cytoplasmic tail of PKD2 did suppress cation current. Liganding of the ectodomain of the PKD1 fusion protein moderately activated cation current. The divalent cation permeability and pharmacological profile of the current has been extended. Inducible expression of the PKD1 fusion in EcR-293 cells was also associated with activation of cation channels and increased Ca2+ entry.

Animals↗

PubMed2002

Prevalence of body dysmorphic disorder in a German college student sample.

The prevalence of body dysmorphic disorder (BDD) was investigated in a non-clinical sample. German college students (n=133; 73.7% female) completed self-report questionnaires assessing BDD, self-esteem, symptoms of depression, obsessive-compulsive disorder and skin picking. Based on our data, seven participants (5.3%) satisfied DSM-IV BDD criteria. Significant differences were found between students with and without BDD in the number of endorsed obsessive-compulsive disorder symptoms. Poor body image was associated with poor self-esteem, symptoms of depression and obsessive-compulsive disorder. One student with BDD also reported severe skin picking. In conclusion, BDD is a common psychiatric disorder in college students.

Adult↗

PubMed2002

Selective processing of emotional information in body dysmorphic disorder.

Body dysmorphic disorder (BDD) is a syndrome characterized by distress about imagined defects in one's appearance. Though categorized as a somatoform disorder, BDD is marked by many characteristics associated with social phobia (e.g., fear of negative evaluation) and obsessive-compulsive disorder (e.g., intrusive thoughts about one's ugliness, checking). In the present experiment, we tested whether BDD patients exhibit selective processing of threat in the emotional Stroop paradigm as do anxiety-disordered patients. Relative to healthy control participants, BDD patients exhibited greater Stroop interference for positive and negative words, regardless of disorder-relevance, than for neutral words. Further analyses suggested that interference tended to be greatest for positive words related to BDD. These data suggest that BDD patients are vulnerable to distraction by emotional cues in general, and by words related to their current concerns in particular. Results suggest that BDD may indeed be related to anxiety disorders such as social phobia.

Adult↗

PubMed2002

Interpretive biases for ambiguous information in body dysmorphic disorder.

Anxiety-disordered patients and individuals with high trait anxiety tend to interpret ambiguous information as threatening. The purpose of this study was to investigate whether interpretive biases would also occur in body dysmorphic disorder (BDD), which is characterized by a preoccupation with imagined defects in one's appearance. We tested whether BDD participants, compared with obsessive-compulsive disorder participants and healthy controls, would choose threatening interpretations for ambiguous body-related, ambiguous social, and general scenarios. As we hypothesized, BDD participants exhibited a negative interpretive bias for body-related scenarios and for social scenarios, whereas the other groups did not. Moreover, both clinical groups exhibited a negative interpretive bias for general scenarios.

Journal Article↗

PubMed2002

A study of parallel implicit and explicit information processing in patients with obsessive-compulsive disorder.

OBJECTIVE: This study examined implicit sequence learning in patients with obsessive-compulsive disorder (OCD) under dual-task conditions. Frontal-striatal networks support implicit learning and are implicated in the pathophysiology of OCD. Neuroimaging data suggest that during implicit learning, OCD patients use neural systems normally active during explicit learning to compensate for striatal dysfunction. METHOD: The authors examined implicit sequence learning in 25 OCD patients and 25 healthy comparison subjects using a dual-task paradigm, with subjects simultaneously engaged in an explicit memory task and an implicit learning task. They predicted that implicit learning in OCD subjects would be disrupted because concurrent explicit information-processing demands would prevent use of compensatory processes. RESULTS: OCD patients failed to show evidence of implicit learning and exhibited a significant deficit in comparison with healthy subjects. CONCLUSIONS: These results are consistent with the hypothesis that concurrent explicit and implicit information-processing demands interfere with implicit learning in OCD patients.

Attention↗

PubMed2002

Comorbid posttraumatic stress disorder: impact on treatment outcome for obsessive-compulsive disorder.

OBJECTIVE: The study tested the effect of comorbid posttraumatic stress disorder (PTSD) on behavior therapy outcome for obsessive-compulsive disorder (OCD). METHOD: Subjects were 15 patients with treatment-refractory OCD who were admitted consecutively to a short-term residential facility. Eight met DSM-IV criteria for comorbid PTSD. Patients participated in coached and self-directed behavior treatments of exposure and response prevention as well as in group treatments targeting specific OCD symptoms and related difficulties. Severity of OCD and depression were assessed at admission and exit. RESULTS: Patients with comorbid PTSD showed no significant improvements in OCD and depression symptoms. OCD and depression symptoms improved significantly more in patients without comorbid PTSD than in patients with comorbid PTSD. CONCLUSIONS: Behavioral treatment (with or without medication) of OCD may be adversely affected by the presence of comorbid PTSD.

Adult↗

PubMed2002

Skin picking in German students. Prevalence, phenomenology, and associated characteristics.

Severe skin picking (SP) is a repetitive, intentionally performed behavior that causes noticeable tissue damage and results in clinically significant distress or impairment. To date, SP has received little attention in the psychiatric literature. This study was conducted to further investigate SP and its characteristics in a German student population. The participants (N = 133) completed various self-report questionnaires. More than 90% (n = 122) reported occasional SP, with six students (4.6%) endorsing significant impairment from recurrent, self-injurious SP. SP was triggered by specific cutaneous stimuli, situations, and emotions. The students primarily squeezed (85%) and scratched (77.4%) the skin, with a primary focus on the face (94.7%) and cuticles (52.6%). About 20% (n = 26) ate the picked tissue afterward. Results suggest SP is an underrecognized problem that occurs on a continuum ranging from mild to severe with generally stable clinical characteristics across cultures.

Adult↗

PubMed2002

Cognitive-behavior therapy for self-injurious skin picking. A case series.

Self-injurious skin picking is characterized by repetitive, ritualistic, or impulsive skin picking that leads to tissue damage and causes significant distress or impairment in daily functioning. Little is known about effective behavioral or cognitive-behavioral treatments for self-injurious skin picking. As described by Azrin and colleagues, habit reversal is a promising behavioral treatment for modifying nervous habits or tics. To the authors' knowledge, only one case series currently exists in the literature that shows self-injurious skin picking, in the absence of an underlying dermatological condition or without psychiatric comorbidity, can be successfully treated with habit reversal. In the current article, the authors describe the implementation and outcome of cognitive-behavior therapy for three patients with severe self-injurious skin picking, two of which had psychiatric comorbidity.

Adaptation, Psychological↗

PubMedDate not supplied

Emotion recognition deficits in body dysmorphic disorder.

Patients with Body Dysmorphic Disorder (BDD) are characterized by excessive concerns about imagined defects in their appearance, most commonly, facial features. In this study, we investigated (1) the ability to identify facial expressions of emotion, and (2) to discriminate single facial features in BDD patients, Obsessive-Compulsive Disorder (OCD) patients, and in healthy control participants. Specifically, their ability for general facial feature discrimination was assessed using the Short Form of the Benton Facial Recognition Test (Benton AL, Hamsher KdeS, Varney NR, Spreen O. Contributions to neuropsychological assessment: a clinical manual. New York: Oxford University Press; 1983). However, findings of the BFRT indicate no differences among the groups. Moreover, participants were presented with facial photographs from the Ekman and Friesen (Ekman P, Friesen W. Unmasking the face: a guide to recognizing emotions from facial cues. Englewood Cliffs, NJ: Prentice-Hall; 1975 and Ekman P, Friesen W. Pictures of facial affect. Palo Alto: Consulting Psychologists Press, 1976) series and were asked to identify the corresponding emotion. The BDD group was less accurate than the control group, but not the OCD group, in identifying facial expressions of emotion. Relative to the control and OCD groups, the BDD group more often misidentified emotional expressions as angry. In contrast to the findings of Sprengelmeyer et al. [Proc. Royal Soc. London Series B: Biol. Sci. 264 (1997),1767], OCD patients did not show a disgust recognition deficit. Poor insight and ideas of reference, common in BDD, might partly result from an emotion recognition bias for angry expressions. Perceiving others as angry and rejecting might reinforce concerns about one's personal ugliness and social desirability.

Adult↗

PubMedDate not supplied

Pathologic hairpulling, skin picking, and nail biting.

BACKGROUND: Pathologic hairpulling (HP), skin picking (SP), and nail biting (NB) are repetitive, intentionally performed behaviors that cause noticeable hair loss or substantial physical damage, and result in clinically significant distress or functional impairment. To date, HP, SP, and NB have received little attention in the psychiatric literature despite being widespread behaviors. METHODS: The present article reviews the up-to-date research findings on these three forms of pathologic behavior, highlighting their similarities and differences. RESULTS: Despite HP, pathologic grooming behaviors have not yet been explicitly included in the diagnostic nomenclature. Phenomenology, triggers, consequences and functionality of HP, SP, and NB are similar, which suggest their joint diagnostic categorization. Sufferers often fail to admit the self-inflicted nature of their physical damage out of shame and embarrassment, which complicates the recognition and differential diagnosis of sufferers. Thus, practitioners need to be particularly attentive to physical signs possibly related to these behavior disorders. CONCLUSIONS: Research suggests that HP, SP, and NB are underrecognized problems that occur on a continuum ranging from mild to severe. Further research is needed, especially regarding the etiology of pathologic HP, SP, and NB, to foster the development of both effective and long-lasting treatments and prevention strategies.

Antidepressive Agents↗

PubMedDate not supplied

Prevalence of symptoms of body dysmorphic disorder and its correlates: a cross-cultural comparison.

The authors investigated the prevalence of body image concerns, body dysmorphic disorder, and related psychiatric symptoms in a group of 101 American students. Results were compared with data from a group of 133 German students. Survey data were collected on body image concerns, self-esteem, depression, anxiety, obsessive-compulsive symptoms, and skin picking. A total of 74.3% of the American students endorsed body image concerns, and 28.7% were preoccupied by them; 4.0% appeared to meet DSM-IV criteria for body dysmorphic disorder. Body esteem was significantly correlated with self-esteem and depressive, anxiety, and obsessive-compulsive symptoms. Body image concerns and preoccupation were significantly greater in American than in German students, although the prevalence of probable body dysmorphic disorder was not.

Adolescent↗