Does pTis exist in HPV-driven tonsillar carcinomas? An ultrastructural review and examination of two cases

Many tonsillar tumors present clinically as cervical nodal metastases and the primary tumor is often difficult to find. HPV-driven tonsillar carcinoma begins in the reticulated crypt epithelium, possibly through viral integration. The basement membrane is not complete in the reticulated crypt epithelium, which may enhance the immune function. We examined the reticulated crypt epithelium in a normal case and five neoplastic tonsils with cervical metastasis as the presenting symptom to further investigate whether tonsil carcinoma in-situ exists. Our results suggest that in-situ carcinoma may need to be excluded from the future staging for human papilloma virus associated tonsillar tumors.     

Does fear expectancy prime fear? An autonomic study in spider phobics

This study investigated whether fear expectancy in phobic individuals induces priming of the defensive system, thus generating a “blind” phobic response even to non-phobic stimuli. We employed a paradigm in which two different visual cues signalled the upcoming picture presentation of either a spider or an innocuous animal (congruent condition). Unknown to the participants, the visual cue was incorrectly followed by a picture from the opposite category on two additional trials (incongruent condition). Cardiac and skin conductance responses were recorded from young adults with (n = 15) or without (n = 14) spider phobia during both the expectation and exposure of these pictures in the congruent and incongruent conditions. In the congruent condition, the autonomic responses during expectation matched the responses during exposure. In particular, non-phobic controls showed an orienting response (bradycardia and moderate skin conductance increase) to both picture categories, while spider phobics showed an orienting response to the innocuous animals and a defence response (tachycardia and marked skin conductance increase) to spiders.     

Intercalated clear cells or pale cells in the sinus node of canine hearts? An ultrastructural study

Two types of sinus nodal cells were responsible for the main differences in the literature concerning the ultrastructure of the sinuatrial node: the intercalated clear cells and pale cells. Canine hearts were arrested by (1) aortic cross clamping, (2) coronary perfusion with the cardioplegic solution St. Thomas, and (3) coronary perfusion with the cardioplegic solution HTK (Custodiol(R)). After fixation by immersion or perfusion the sinus node tissue was prepared for electron microscopy. Following cardioplegic arrest and perfusion fixation, three nodal cell types in the non-ischemic sinuatrial node were observed: typical nodal cells, transitional cells, and intercalated clear cells. Less than 1% of the non-ischemic sinuatrial cells were intercalated clear cells, surrounded by typical nodal cells or transitional cells. The contractile apparatus of the intercalated clear cells was extremely poorly developed. Great structural variations in the mitochondria were observed in intercalated clear cells, variations that would not appear under conditions of ischemia. In contrast, after 15-25 min of ischemia at 25 degrees C the appearance of the sinus nodal cells was strikingly different from that of the non-ischemic sinuatrial cells. More than 10% of the nodal cells showed typical ischemic alterations, e.g., mitochondrial swelling, clumping of nuclear chromatin, loss of glycogen particles, and cell swelling in varying degrees. Because they look very pale, these nodal cells have been described as pale cells in the literature. Intercalated clear cells appear mainly in non-ischemic nodal tissue. Pale cells are ischemically damaged sinus nodal cells.     

Intercalated clear cells or pale cells in the sinus node of canine hearts? An ultrastructural study

Two types of sinus nodal cells were responsible for the main differences in the literature concerning the ultrastructure of the sinuatrial node: the intercalated clear cells and pale cells. Canine hearts were arrested by (1) aortic cross clamping, (2) coronary perfusion with the cardioplegic solution St. Thomas, and (3) coronary perfusion with the cardioplegic solution HTK (Custodiol®). After fixation by immersion or perfusion the sinus node tissue was prepared for electron microscopy. Following cardioplegic arrest and perfusion fixation, three nodal cell types in the non‐ischemic sinuatrial node were observed: typical nodal cells, transitional cells, and intercalated clear cells. Less than 1% of the non‐ischemic sinuatrial cells were intercalated clear cells, surrounded by typical nodal cells or transitional cells. The contractile apparatus of the intercalated clear cells was extremely poorly developed. Great structural variations in the mitochondria were observed in intercalated clear cells, variations that would not appear under conditions of ischemia. In contrast, after 15–25 min of ischemia at 25°C the appearance of the sinus nodal cells was strikingly different from that of the non‐ischemic sinuatrial cells. More than 10% of the nodal cells showed typical ischemic alterations, e.g., mitochondrial swelling, clumping of nuclear chromatin, loss of glycogen particles, and cell swelling in varying degrees. Because they look very pale, these nodal cells have been described as pale cells in the literature. Intercalated clear cells appear mainly in non‐ischemic nodal tissue. Pale cells are ischemically damaged sinus nodal cells. Anat Rec 260:33–41, 2000. © 2000 Wiley‐Liss, Inc.     

Are human placental bed giant cells merely aggregates of small mononuclear trophoblast cells? An ultrastructural and immunocytochemical study

The ultrastructure of placental bed giant cells in early human pregnancies of 7-12 weeks gestational age is described. Their nature and function was further characterized by confocal immunofluorescence microscopy of paraffin sections labelled for cytokeratin, gap junction connexins (CX) 32 or 43, and placental hormones, alpha-human chorionic gonadotrophin (alpha-HCG) and human placental lactogen (HPL). Placental bed giant cells were observed with two phenotypes; as single large trophoblast cells containing one or more nuclear profiles in a voluminous cytoplasm, and as cell aggregates comprising mononuclear trophoblast cells in close apposition separated by narrow intercellular spaces. Cells within the aggregates are attached to one another by desmosomes, and also possess gap junctions as shown by immunolabelling for CX32 and CX43. By contrast, gap junctions were absent in the true multinucleated giant cells. Organelles present within the cytoplasm of the giant cells and their immunoreactivity for HPL and alpha-HCG suggest protein synthesis.     

Does development affect the error-related negativity of impaired and skilled readers? An ERP study

Previous findings of reduced error-related and correct-related negativities (ERN/CRN) and semantic N400 responses associated with reading errors among impaired adult readers led to the current study on age effects on these components. Event-related potentials (ERPs) were recorded from 43 adolescents and 46 adults, including skilled readers and persons with a history of reading disability, on a lexical decision task. Adolescents exhibited smaller ERN amplitudes and larger N400 amplitudes during reading errors, presumably due to the late maturation of the prefrontal cortex. The ERN amplitude difference between impaired and skilled readers was smaller in adolescents than adults, and adolescents exhibited a smaller N400 difference between correct and erroneous responses than adults. ERN amplitude increased with age in impaired readers. It is postulated that the still developing mental lexicon among adolescents results in greater semantic effort and reduced ERN differences.     

Does ICSI affect early serum beta-HCG in pregnancies achieved after IVF?

This study was conducted to compare early serum human chorionic gonadotrophin (HCG) concentrations in singleton pregnancies achieved after intracytoplasmic sperm injection (ICSI), with those achieved after conventional in-vitro fertilization (IVF). Early serum HCG, 14-16 days after embryo transfer, was analysed in 99 IVF pregnancies achieved after ICSI (group A), and compared to 105 conventional IVF pregnancies (group B). All women were treated at the IVF Unit, Lis Maternity Hospital. Records were studied retrospectively. The mean +/- SE serum HCG concentration on day 14 after embryo transfer in group A was 190.5 +/- 17.4 mIU/ml, compared to 195.7 +/- 14.03 mIU/ml in group B. HCG concentration 14 days after embryo transfer in both groups A and B was higher in women with mechanical factor than in couples with male factor infertility or unexplained infertility (246 +/- 31.4, 183.3 +/- 16.4, 177.98 +/- 14.3 mIU/ml respectively). On the 16th day after embryo transfer, the HCG concentration increased, and the difference between the groups was maintained. Only in the subgroup of unexplained infertility did we find a difference in concentrations of HCG between ICSI and conventional IVF: on the 16th day following embryo transfer in this group there was a significant difference in HCG concentrations (395. 8 +/- 21 and 545.6 +/- 45.7 respectively; P = 0.04). HCG concentrations did not differ overall in the conventional IVF pregnancies compared with those achieved by ICSI. However, a statistical difference in early serum HCG concentrations was found in relation to the aetiology of infertility.     

Does disorganised attachment lead to auditory hallucinations via dissociation? An experimental study with an analogue sample

Objectives

Auditory hallucinations (such as hearing voices) are common in clinical and non-clinical populations. Many people who hear voices also report early adversity and have an insecure attachment style. Current cognitive models suggest that dissociation mediates an association between disorganised attachment and auditory hallucinations, but this has not been tested experimentally.

Design

We recruited a non-clinical analogue sample highly predisposed to auditory hallucinations and utilised an experimental design to examine the impact of disorganised attachment imagery on hallucinatory experiences, and whether dissociation mediates an expected association.

Methods

Participants completed self-report measures of state auditory hallucinations and dissociation before and after random allocation to secure or disorganised attachment conditions.

Results

Attachment imagery did not affect auditory hallucinations. Both secure and disorganised attachment conditions increased state dissociation. Secure attachment imagery reduced paranoia, but state dissociation did not mediate this effect. An exploratory analysis found that trait dissociation fully accounted for the association between trait-disorganised attachment and hallucinatory experience while controlling for paranoia.

Conclusions

Secure attachment imagery reduces paranoia but not auditory hallucinations and the impact on paranoia is not mediated by dissociation. Secure attachment imagery may be useful in reducing fears and distress associated with voices, rather than the frequency or severity of hallucinations. Disorganised attachment may increase hallucinatory experiences for people vulnerable to dissociation. Trait dissociation should be assessed in clinical settings and addressed where indicated as a means of targeting vulnerability to distressing voices.     

Does the frequency of the antecedent noun affect the resolution of pronominal anaphors? An ERP study

Behavioral studies investigating the influence of the relative word frequency of antecedent nouns on the processing of anaphoric pronouns have yielded contradictory results. While some researchers found no effect of an antecedent's frequency of occurrence on coreference resolution [J. Simner, R. Smyth, Phonological activation in anaphoric lexical access (ALA), Brain Lang. 68 (1999) 40-45], others report shorter reading times for pronouns referring to low compared to high frequency nouns [R.G.P. van Gompel, A. Majid, Antecedent frequency effects during the processing of pronouns, Cognition 90 (2004) 255-264]. Using event-related potentials, our study aimed to further investigate the issue. Participants were presented with sentence pairs, of which the first contained either a high frequency, a middle frequency or a low frequency noun. The second sentence contained a pronoun which referred back to the noun in the first sentence. ERP waves were determined, time-locked to both the nouns and the anaphoric pronouns. We observed a graded N400 effect for antecedents of the three frequency classes with amplitudes reversely related to the word's lexical frequency. Coreferential pronouns elicited a P300, with amplitudes dependent on the noun's relative frequency of occurrence, i.e. the lower the antecedent's word frequency, the higher was the amplitude of the P300. This amplitude effect at the pronoun is interpreted in terms of the allocation of attentional resources to salient discourse entities.     

Does marriage and relationship education work? A meta-analytic study

In this meta-analytic study, the authors examined the efficacy of marriage and relationship education (MRE) on 2 common outcomes: relationship quality and communication skills. A thorough search produced 86 codable reports that yielded 117 studies and more than 500 effect sizes. The effect sizes for relationship quality for experimental studies ranged from d = .30 to .36, while the communication skills effect sizes ranged from d = .43 to .45. Quasi-experimental studies generated smaller effect sizes, but these appeared to be due to pretest group differences. Moderate-dosage programs produced larger effect sizes than did low-dosage programs. For communication skills, published studies had larger effects than those of unpublished studies at follow-up; there were no publication differences for relationship quality. There was no evidence of a gender difference. Unfortunately, a lack of racial/ethnic and economic diversity in the samples prevented reliable conclusions about the effectiveness of MRE for disadvantaged couples, a crucial deficit in the body of research. In addition, intervention outcomes important to policy makers, such as relationship stability and aggression, rarely have been addressed.     

Can subitizing survive the attentional blink? An ERP study

This study was done to test whether subitizing versus counting are attention demanding based on whether they can be performed during the attentional blink (AB). ERPs were recorded while participants performed a task requiring them to judge the number of dots presented and this judgment task either followed the presentation of a task-relevant item in a rapid stimulus presentation stream (dual-task) or the potential target was task irrelevant (single-task). The behavioral data demonstrated that T2 accuracies decreased as a function of the number of dots not only in counting range, but also in subitizing range. The ERP results showed a delayed P3 component in the dual-task condition, and this was equally true for both subitizing and counting conditions. Furthermore, the P3 amplitude was reduced during the AB, and this was still equally true for both the subitizing and counting conditions. The present results suggest that both subitizing and counting require attention, and that subitizing is not a purely pre-attentive process.     

An intracranial event-related potential study on transformational apparent motion. Does its neural processing differ from real motion?

How the brain processes visual stimuli has been extensively studied using scalp surface electrodes and magnetic resonance imaging. Using these and other methods, complex gratings have been shown to activate the ventral visual stream, whereas moving stimuli preferentially activate the dorsal stream. In the current study, a first experiment assessed brain activations evoked by complex gratings using intracranial electroencephalography in 10 epileptic patients implanted with subdural electrodes. These stimuli of intermediate levels of complexity were presented in such a way that transformational apparent motion (TAM) was perceived. Responses from both the ventral and the dorsal pathways were obtained. The response characteristics of visual area 4 and the fusiform cortex were of similar amplitudes, suggesting that both ventral areas are recruited for the processing of complex gratings. On the other hand, TAM-induced responses of dorsal pathway areas were relatively noisier and of lower amplitudes, suggesting that TAM does not activate motion-specific structures to the same extent as does real motion. To test this hypothesis, we examined the activity evoked by TAM in comparison to the one produced by real motion in a patient implanted with the same subdural electrodes. Findings demonstrated that neural response to real motion was much stronger than that evoked by TAM, in both the primary visual cortex (V1) and other motion-sensitive areas within the dorsal pathway. These results support the conclusion that apparent motion, even if perceptually similar to real motion, is not processed in a similar manner.     

Does controlled ovarian stimulation prior to chemotherapy increase primordial follicle loss and diminish ovarian reserve? An animal study

BACKGROUND: Storage of embryos for fertility preservation before chemotherapyis widely practiced. For multiple oocyte collection, the ovariesare hyperstimulated with gonadotrophins that significantly alterovarian physiology. The effects of ovarian stimulation priorto chemotherapy on future ovarian reserve were investigatedin an animal model. METHODS: Cyclophosphamide (Cy) in doses of 0, 50 or 100 mg/kg was administeredto 38 adult mice (control, unstimulated). A second group of12 mice were superovulated with equine chorionic gonadotrophin(eCG, 10 IU on Day 0) before Cy administration; hCG (10 IU)was administered (Day 2) followed by 0, 50 or 100 mg/kg Cy (Day4). In both groups ovaries were removed, serially sectioned(7-day post-Cy), primordial follicles were counted and differencesbetween groups evaluated. RESULTS: Follicle number dropped from 469 ± 24 (mean ±SE) to 307 ± 27 and 234 ± 19 with 50 or 100 mg/kgCy, respectively (P < 0.0001). In the eCG pretreated group,follicle count dropped from 480 ± 31 to 345 ±16 and 211 ± 26 when 50 or 100 mg/kg Cy were administered(P < 0.0001). There were no significant differences in folliclecount between the pretreated eCG group and controls for eachchemotherapy dose. CONCLUSIONS: This animal study indicates that ovarian stimulation beforeadministration of Cy does not adversely affect ovarian reservepost-treatment. These results provide support for the safetyof fertility preservation using ovarian stimulation and IVF–embryocryopreservation procedures prior to chemotherapy.     

Mesangial cell necrosis in Thy 1 glomerulonephritis – an ultrastructural study

Cell death is central to many physiological and pathological processes. As tissue reactions to the two forms of cell death, necrosis and apoptosis, differ, it is critical to distinguish between them. Although ultrastructure is still the definitive means of assessing this, there are very few in vivo studies. Administration of anti-Thy 1 antibody in rats is a model of acute glomerular mesangial cell death due to their expression of the Thy 1.1 epitope. The nature of this process is unclear; apoptosis was suggested from early morphological studies and recent in vitro effects of anti-Thy 1.1 antibody. We have re-examined the changes by electron microscopy, and identified a process of cell necrosis starting within 30 min of anti-Thy1.1 antibody administration. Although there was chromatin condensation, the necrotic features distinctive from apoptosis were: loss of nuclear membranes, cell swelling and degeneration of cytoplasmic organelles, with liberation of chromatin and organelles into the interstitium causing acute inflammation without phagocytic uptake of apoptotic bodies. These findings accord with the known complement dependence of this model. Ultrastructure is a valuable means of differentiating between in vivo necrosis and apoptosis and this is important for understanding the pathogenesis of injury and subsequent tissue responses. Received: 10 September 1999 / Accepted: 23 November 1999     

Apoptosis in myocarditis and dilated cardiomyopathy: Does enterovirus genome persistence protect from apoptosis? — An endomyocardial biopsy study

The purpose of this study was to examine the role of apoptosis in myocarditis and dilated cardiomyopathy. Apoptosis is an active energy-consuming mechanism of cell death in several cardiac diseases in different quality and quantity. METHODS: Endomyocardial biopsies from 81 patients with active (1) and chronic myocarditis (10), dilated cardiomyopathy with inflammation (DCMi; 10) and without inflammation (DCM; 20), with borderline myocarditis and positive PCR for cytomegalovirus-DNA (6), adenovirus-DNA, or enterovirus-RNA (7), and controls (17) were analysed. Apoptosis was detected by using the TUNEL method. The highest rate of apoptotic cardiocytes was found in active and chronic myocarditis. One patient with severe active myocarditis demonstrated 6.15% of apoptotic cardiocytes. Mean percentage of apoptotic cardiocytes in chronic myocarditis was significantly increased (0.61+/-1.25%) when compared to controls (0.01+/-0.04%, P<.05). Particularly, patients with cytomegalovirus-DNA persistence in borderline myocarditis had an elevated rate of apoptosis (0.34+/-0.68%, P<.05). Increased rates of apoptosis were found in borderline myocarditis with adenovirus-DNA persistence (0.20+/-0.57%) and in DCM (0.06+/-0.15%). Only a nonsignificant increase of apoptotic cardiocytes was found in DCMi (0.03+/-0.08%). No apoptosis was found in patients with enteroviral genome persistence in borderline myocarditis. CONCLUSIONS: Apoptosis of cardiac cells is increased in myocarditis and dilated cardiomyopathy, being highest in severe active myocarditis. Apoptosis thus contributes to cell death in active myocarditis and may play a role not to be neglected in dilated cardiomyopathy. Enteroviruses seem to have anti-apoptotic effects, because no apoptosis at all was found in the myocardium.     

Is the SF 36 sensitive to sleep disruption? A study in subjects with sleep apnoea

SUMMARY  The objectives of this study were to test the sensitivity of the short form 36 health survey questionnaire (SF 36) to sleep disruption in patients with obstructive sleep apnoea (OSA) and assess its use as an outcome measure for treatment with nasal continuous positive airway pressure (CPAP). Two hundred and twenty-three subjects under investigation for snoring and/or daytime somnolence completed the questionnaire at presentation and again after a six month period. Subjects with OSA requiring treatment scored lower on all dimensions of the SF 36 ( P <0.05) than normative scores for the general population. The largest differences were for vitality (24%) and social functioning (27.9%). After six months of treatment with CPAP there was an improvement in all scores and the score for vitality was no longer significantly different from that of the general population. The SF 36 is sensitive to the effects of sleep disruption in subjects with obstructive sleep apnoea, is a useful outcome measure for treatment with CPAP and its value in other sleep disorders should be assessed.