Buchbesprechungen

Ohne Zusammenfassung     

Skin testing in farmers' lung disease

Intradermal skin tests with a culture filtrate antigen of Micropolyspora faeni grown on a synthetic medium were performed on patients with farmers' lung disease (FLD) and well farmers with and without antibodies to a panel of FLD antigens. Seventy-five percent of the FLD patients, 79% of the well farmers with M. faeni antibody, and 5% of well farmers without M. faeni antibody had a 2+ or greater intradermal immediate skin-test reaction. Prausnitz-Küstner (P-K) reactions were positive using serum of M. faeni immediate skin test-positive FLD patients. IgG-rich fractions from a staphylococcal protein A-Sepharose column of such serum contained the sensitizing factor whereas IgG-depleted fractions did not. M. faeni—specific IgE could not be detected in serum by a polystyrene radioimmunoassay. Positive late-onset (6-hr) skin tests occurred only in FLD patients and farmers with precipitating antibody. Biopsy specimens of the 6-hr reactions revealed a generalized dermal and perivascular polymorphonuclear infiltrate with deposits of immunoglobulin and complement about blood vessels. The skin-sensitizing factor noted in FLD patients and well farmers with antibody is not disease specific. This factor appears to be associated with the IgG-rich fraction of serum, and its role in the pathogenesis of FLD is unclear.     

Acetylcholine receptor epitope in proteins of myasthenia gravis-associated thymomas and non-thymic tissues

Immunohistochemical studies have shown that almost all thymomas of myasthenia gravis (MG) patients contain proteins which share antigenic determinants with the nicotinic acetylcholine receptor (AChR) of human muscle. Here we describe one of the proteins (p153) which (1) is not part of a compound structure, (2) has a MW of 153 kd, (3) has an isoelectric point of 5.0, and (4) is probably free of sugar residues. The protein does not bind mAb to the main immunogenic region of the AChR and has no alpha-bungarotoxin (alpha-btx) binding site. p153 was not found in both normal tissues and a variety of tumours. However, the epitope defined by mAb155 also occurs in at least two other proteins (from muscle and TE671 cells) which have MW different from 153 kd and which are unrelated to AChR. Experiments presented elsewhere [Geuder et al., this volume] show that there are no proteins in thymomas which share an extensive molecular homology with the AChR. All these findings suggest that p153 is unrelated to the AChR. As p153 is the only protein demonstrated in thymomas which is significantly correlated with MG and which shares an antigenic determinant with AChR, p153 is a candidate protein determining the AChR-specificity of the autoimmune process in MG.     

Natural history of endemic type D retrovirus infection and acquired immune deficiency syndrome in group-housed rhesus monkeys

A 2.5-year epidemiologic study of a breeding group of rhesus monkeys (Macaca mulatta), which is a focus of endemic simian acquired immunodeficiency syndrome (SAIDS), demonstrated a strong association between the occurrence of SAIDS and infection with a type D retrovirus, SAIDS retrovirus serotype 1 (SRV-1). Of 23 healthy "tracer" juvenile rhesus monkeys, 19 (83%) died with SAIDS within 9 months of introduction into the resident SAIDS-endemic population. In contrast, 21 healthy "sentinel" juvenile rhesus monkeys placed in the same outdoor enclosure but denied physical contact with the SAIDS-affected group by a 10-foot-wide "buffer zone" remained free of SRV-1, SRV-1 antibody, and disease for 2.5 years. The SAIDS-specific mortality rate was significantly higher in juveniles than in adults. In repeated serologic testing, the overall prevalence of SRV-1 antibody ranged from 68 to 85%. Antibody prevalence increased with age. Seroconversion was found to be a poor indicator of infection rate, as approximately 50% of virus-positive juvenile monkeys had no antibody detectable by enzyme-linked immunosorbent assay. Repeated viral isolations from all animals revealed 1) SRV-1 viremia with clinical SAIDS; 2) persistent viremia and viral shedding in apparently healthy animals; 3) transient viremia and clinical recovery; 4) intermittent viremia, suggesting activation of latent infections; and 5) viremia in a 1-day-old infant, suggesting transplacental transmission. The prevalence of SRV-1 antibody in SAIDS-free breeding groups of rhesus monkeys was 4%. The seroprevalence of antibodies against human T-cell leukemia virus type 1 (HTLV-1), human immunodeficiency virus (HIV), and simian immunodeficiency virus (SIV; formerly STLV-III) was uniformly low or absent in both SAIDS-free and SAIDS-affected groups of rhesus monkeys, demonstrating that these retroviruses are not etiologically linked to SAIDS at the California Primate Research Center.     

Comparative study of complications after primary and revision transsphenoidal endoscopic surgeries

Neurosurgical Review - A preferred treatment for residual/recurrent pituitary adenomas has not been established. The existence of higher complication rates for revision surgeries remains under...     

Immunocytochemical characteristics of small cell lung carcinoma associated with the Lambert-Eaton myasthenic syndrome.

The Lambert-Eaton myasthenic syndrome (LEMS) is characterized by the presence of IgG antibodies to motor nerve terminals, and associates with small cell lung carcinoma in more than 60% of cases. We have carried out a comparative immunocytochemical study on small cell lung carcinoma (SCLC) in five LEMS cases and six non-LEMS cases, using antibodies to tumor markers, MHC Class I and II, macrophages and lymphocytes. The authors found a reduced expression of the 200Kd neurofilament antigen and of MHC Class I antigens in the LEMS cases as well as a greater infiltration of activated macrophages. It is suggested that these findings are consistent with the view that SCLC antigenic determinants trigger the autoantibody response in SCLC-LEMS.     

Females' perception of date rape: an examination of two contextual variables

This study examined the role of perceived token resistance and previous sexual contact on women's ability to discriminate when a female wants her partner to stop his sexual advances. Participants included 101 White female undergraduate students and were randomly assigned to one of the four conditions: 1) perceived resistance with genital contact; 2) no resistance with genital contact; 3) perceived resistance with no genital contact; and 4) no resistance without genital contact. Subjects listened to an audiotaped date rape after being informed of the couple's sexual history based on the condition assigned to them. They were also informed that the couple had been on five previous dates, in which the man had manipulated the woman's breasts or genitals. In addition, the woman did not object to this contact, or the woman initially objected to the contact but subsequently stopped resisting contact. Participants in the perceived token resistance conditions took significantly longer to determine when the man should refrain from attempting further sexual contact. The findings of this study could be used to increase information on date rape, to educate individuals about the responses associated with date rape, and to reinforce rules concerning appropriate sexual behavior.     

Linking Clients from HIV Antibody Counseling and Testing to Prevention Services

The effectiveness of HIV antibody counseling and testing as a prevention intervention is limited: persons testing seronegative do not usually change their risk behaviors, some actually increase their risk behaviors, and decreases in risk behaviors are usually short-lived. Referrals to additional prevention and other needed services are therefore recommended, although the extent and determinants of referral provision for persons testing seronegative are unknown. We assessed the prevalence of referrals and the association between risk behaviors and prevention referrals among seronegatives. We reviewed HIV testing and referral data on all persons receiving confidential seronegative test results in San Francisco (SF) in the first 10 months of 1995 (n = 5,595), and gathered more detailed referral information at the municipal STD clinic from November 1995 through May 1996 (n = 747). The overall prevalence of referrals was low: a referral was given to 19.1% of the SF sample and 10.6% of the STD clinic sample; 15.4% of the SF sample and 5.9% of the STD clinic sample received a prevention referral. Injection drug users (IDUs) were the most likely to receive a prevention referral (48.5% of SF IDUs, 36.4% of STD clinic IDUs); men having sex with men and women with high-risk partners were also more likely to get a prevention referral than others. For SF IDUs, unsafe sex and needle sharing were not associated with an increased likelihood of receiving a prevention referral. Opportunities to link high-risk clients from counseling and testing to HIV prevention services are being missed. The referral component of HIV counseling and testing should be improved.     

Inducible genetic suppression of neuronal excitability.

Graded, reversible suppression of neuronal excitability represents a logical goal of therapy for epilepsy and intractable pain. To achieve such suppression, we have developed the means to transfer "electrical silencing" genes into neurons with sensitive control of transgene expression. An ecdysone-inducible promoter drives the expression of inwardly rectifying potassium channels in polycistronic adenoviral vectors. Infection of superior cervical ganglion neurons did not affect normal electrical activity but suppressed excitability after the induction of gene expression. These experiments demonstrate the feasibility of controlled ion channel expression after somatic gene transfer into neurons and serve as the prototype for a novel generalizable approach to modulate excitability.     

In Process Citation

Pure word deafness (auditory verbal agnosia) is characterized by an impairment of auditory comprehension, repetition of verbal material and writing to dictation whereas spontaneous speech production and reading largely remain unaffected. Sometimes, this syndrome is preceded by complete deafness (cortical deafness) of varying duration. Perception of vowels and suprasegmental features of verbal utterances (e.g., intonation contours) seems to be less disrupted than the processing of consonants and, therefore, might mediate residual auditory functions. Often, lip reading and/or slowing of speaking rate allow within some limits to compensate for speech comprehension deficits. Apart from a few exceptions, the available reports of pure word deafness documented a bilateral temporal lesion. In these instances, as a rule, identification of nonverbal (environmental) sounds, perception of music, temporal resolution of sequential auditory cues and/or spatial localization of acoustic events were compromised as well. The observed variable constellation of auditory signs and symptoms in central hearing disorders following bilateral temporal disorders, most probably, reflects the multitude of functional maps at the level of the auditory cortices subserving, as documented in a variety of non-human species, the encoding of specific stimulus parameters each. Thus, verbal/nonverbal auditory agnosia may be considered a paradigm of distorted "auditory scene analysis" (Bregman 1990) affecting both primitive and schema-based perceptual processes. It cannot be excluded, however, that disconnection of the Wernicke-area from auditory input (Geschwind 1965) and/or an impairment of suggested "phonetic module" (Liberman 1996) contribute to the observed deficits as well. Conceivably, these latter mechanisms underly the rare cases of pure word deafness following a lesion restricted to the dominant hemisphere. Only few instances of a rather isolated disruption of the discrimination/identification of nonverbal sound sources, in the presence of uncompromised speech comprehension, have been reported so far (nonverbal auditory agnosia). As a rule, unilateral right-sided damage has been found to be the relevant lesion.