Noninvasive therapy of incidental de novo renal cell carcinoma in a kidney allograft 12 years after transplantation: report of a case and review of literature.

BACKGROUND: Immunosuppressive therapy increases the incidence of posttransplantation cancer. Primary renal cell carcinoma (RCC) represents 4.6% of all cancers in transplant recipients. The treatment options for RCC in a renal allograft include radical nephrectomy or nephron-sparing surgery. We report the case of a patient who underwent percutaneous radiofrequency ablation (RFA) of a RCC in the grafted kidney. PATIENT AND METHODS: Twelve years after undergoing heterotopic, allogenic kidney transplantation, a de novo lesion was diagnosed in the upper pole of the kidney graft in a 77-year-old patient during routine duplex ultrasonography. The magnetic resonance image showed a spherical lesion of 17 mm in diameter, which undoubtedly showed radiological signs of a RCC. After adequately informing the patient about alternative treatment strategies and the associated risks, we made an interdisciplinary decision for a percutaneous RFA of the lesion. RESULTS: After the intervention, graft function remained unchanged and is still good at 6 months with no signs of local recurrence on follow-up MRI. A small coagulation defect at the site of the former lesion was the only morphological change. There was also no evidence of distant tumor spread. CONCLUSION: Percutaneous RFA seems an acceptable, allograft-preserving treatment option associated with low morbidity and mortality for RCC in a renal allograft considering the significant risks associated with open partial nephrectomy in a kidney graft.

[Analgesia in pediatric outpatient surgery]. / Schmerztherapie bei ambulanten Operationen im Kindesalter.

A number of surgical procedures for pediatric patients can be suitably performed in an outpatient setting. The advantages are impressive: reduced costs, lower rate of infection, avoidance of hospitalization with the inherent psychological stress, and timely return of the patients to their familiar home environment. An essential feature of the quality of outpatient surgery is the efficacy of the perioperative pain therapy for which a multimodal approach has proven to be very effective: workflow tailored to children's needs, ambiance appropriate for children, and pharmacological analgesia. In the preliminary counseling session it is imperative that parents and children receive detailed information on procedures (role playing, modeling). Associated unpleasant factors prior to induction of anesthesia should be avoided. The primary element of pharmacological analgesia is regional anesthesia; additional options are paracetamol, nonsteroidal antirheumatic agents (be aware of the highest dosages!), and opioids. When opioids are employed, care should be taken that monitoring standards in the recovery room are not lowered and include pulsoxymetry. Because of the clearly elevated rate of postoperative nausea and vomiting related to perioperative administration of opioids, the lower dosage level should be chosen. This article presents concepts of perioperative analgesia.

[Prophylactic gastric surgery]. / Prophylaktische Chirurgie des Magens.

A premalignant condition with high risk of gastric cancer is the basis for prophylactic gastric surgery. The germline mutation carrier in the E-cadherin gene has a lifetime risk of 70-80% for diffuse-type gastric cancer, and high-grade intraepithelial neoplasia has a 60-70% gastric cancer risk. Other premalignant conditions such as HNPCC syndrome (5% gastric cancer) and low-grade intraepithelial neoplasia (10% risk) are moderate risk factors for developing gastric cancer. They do not justify prophylactic surgery, but surveillance is required. In case high-grade intraepithelial neoplasia or early gastric cancer is detected, an option is extended radicality with total gastrectomy instead of subtotal gastric resection. Positive family history and early-onset of gastric cancer are risk factors to consider when discussing prophylactic gastrectomy or extended radicality.

Brain imaging of language plasticity in adopted adults: can a second language replace the first?

Do the neural circuits that subserve language acquisition lose plasticity as they become tuned to the maternal language? We tested adult subjects born in Korea and adopted by French families in childhood; they have become fluent in their second language and report no conscious recollection of their native language. In behavioral tests assessing their memory for Korean, we found that they do not perform better than a control group of native French subjects who have never been exposed to Korean. We also used event-related functional magnetic resonance imaging to monitor cortical activations while the Korean adoptees and native French listened to sentences spoken in Korean, French and other, unknown, foreign languages. The adopted subjects did not show any specific activations to Korean stimuli relative to unknown languages. The areas activated more by French stimuli than by foreign stimuli were similar in the Korean adoptees and in the French native subjects, but with relatively larger extents of activation in the latter group. We discuss these data in light of the critical period hypothesis for language acquisition.

Distinct cortical areas for names of numbers and body parts independent of language and input modality.

Some models of word comprehension postulate that the processing of words presented in different modalities and languages ultimately converges toward common cerebral systems associated with semantic-level processing and that the localization of these systems may vary with the category of semantic knowledge being accessed. We used functional magnetic resonance imaging to investigate this hypothesis with two categories of words, numerals, and body parts, for which the existence of distinct category-specific areas is debated in neuropsychology. Across two experiments, one with a blocked design and the other with an event-related design, a reproducible set of left-hemispheric parietal and prefrontal areas showed greater activation during the manipulation of topographical knowledge about body parts and a right-hemispheric parietal network during the manipulation of numerical quantities. These results complement the existing neuropsychological and brain-imaging literature by suggesting that within the extensive network of bilateral parietal regions active during both number and body-part processing, a subset shows category-specific responses independent of the language and modality of presentation.

Correlates of linguistic rhythm in the speech signal.

Spoken languages have been classified by linguists according to their rhythmic properties, and psycholinguists have relied on this classification to account for infants' capacity to discriminate languages. Although researchers have measured many speech signal properties, they have failed to identify reliable acoustic characteristics for language classes. This paper presents instrumental measurements based on a consonant/vowel segmentation for eight languages. The measurements suggest that intuitive rhythm types reflect specific phonological properties, which in turn are signaled by the acoustic/phonetic properties of speech. The data support the notion of rhythm classes and also allow the simulation of infant language discrimination, consistent with the hypothesis that newborns rely on a coarse segmentation of speech. A hypothesis is proposed regarding the role of rhythm perception in language acquisition.

Adaptation to time-compressed speech: phonological determinants.

Perceptual adaptation to time-compressed speech was analyzed in two experiments. Previous research has suggested that this adaptation phenomenon is language specific and takes place at the phonological level. Moreover, it has been proposed that adaptation should only be observed for languages that are rhythmically similar. This assumption was explored by studying adaptation to different time-compressed languages in Spanish speakers. In Experiment 1, the performances of Spanish-speaking subjects who adapted to Spanish, Italian, French, English, and Japanese were compared. In Experiment 2, subjects from the same population were tested with Greek sentences compressed to two different rates. The results showed adaptation for Spanish, Italian, and Greek and no adaptation for English and Japanese, with French being an intermediate case. To account for the data, we propose that variables other than just the rhythmic properties of the languages, such as the vowel system and/or the lexical stress pattern, must be considered. The Greek data also support the view that phonological, rather than lexical, information is a determining factor in adaptation to compressed speech.

Language discrimination by human newborns and by cotton-top tamarin monkeys.

Humans, but no other animal, make meaningful use of spoken language. What is unclear, however, is whether this capacity depends on a unique constellation of perceptual and neurobiological mechanisms or whether a subset of such mechanisms is shared with other organisms. To explore this problem, parallel experiments were conducted on human newborns and cotton-top tamarin monkeys to assess their ability to discriminate unfamiliar languages. A habituation-dishabituation procedure was used to show that human newborns and tamarins can discriminate sentences from Dutch and Japanese but not if the sentences are played backward. Moreover, the cues for discrimination are not present in backward speech. This suggests that the human newborns' tuning to certain properties of speech relies on general processes of the primate auditory system.

Correlates of linguistic rhythm in the speech signal.

Spoken languages have been classified by linguists according to their rhythmic properties, and psycholinguists have relied on this classification to account for infants' capacity to discriminate languages. Although researchers have measured many speech signal properties, they have failed to identify reliable acoustic characteristics for language classes. This paper presents instrumental measurements based on a consonant/vowel segmentation for eight languages. The measurements suggest that intuitive rhythm types reflect specific phonological properties, which in turn are signaled by the acoustic/phonetic properties of speech. The data support the notion of rhythm classes and also allow the simulation of infant language discrimination, consistent with the hypothesis that newborns rely on a coarse segmentation of speech. A hypothesis is proposed regarding the role of rhythm perception in language acquisition.

Language identification with suprasegmental cues: a study based on speech resynthesis.

This paper proposes a new experimental paradigm to explore the discriminability of languages, a question which is crucial to the child born in a bilingual environment. This paradigm employs the speech resynthesis technique, enabling the experimenter to preserve or degrade acoustic cues such as phonotactics, syllabic rhythm, or intonation from natural utterances. English and Japanese sentences were resynthesized, preserving broad phonotactics, rhythm, and intonation (condition 1), rhythm and intonation (condition 2), intonation only (condition 3), or rhythm only (condition 4). The findings support the notion that syllabic rhythm is a necessary and sufficient cue for French adult subjects to discriminate English from Japanese sentences. The results are consistent with previous research using low-pass filtered speech, as well as with phonological theories predicting rhythmic differences between languages. Thus, the new methodology proposed appears to be well suited to study language discrimination. Applications for other domains of psycholinguistic research and for automatic language identification are considered.

Signed and spoken language: a unique underlying system?

Sign language has only recently become a topic of investigation in cognitive neuroscience and psycholinguistics. In this paper, we review research from these two fields; in particular, we compare spoken and signed language by looking at data concerning either cortical representations or early acquisition. As to cognitive neuroscience, we show that clinical neuropsychological data regarding sign language is partially inconsistent with imaging data. Indeed, whereas both clinical neuropsychology and imagery show the involvement of the left hemisphere in sign language processing, only the latter highlights the importance of the right hemisphere. We discuss several possible interpretations of these contrasting findings. As to psycholinguistics, we survey research on the earliest stages of the acquisition of spoken language, and consider these stages in the acquisition of sign language. We conjecture that under favorable circumstances, deaf children exploit sign input to gain entry into the language system with the same facility as hearing children do with spoken input. More data, however, are needed in order to gain a fuller understanding of the relation of different kinds of natural languages to both the underlying anatomical representations and their early acquisition.

The bilingual brain. Proficiency and age of acquisition of the second language.

Functional imaging methods show differences in the pattern of cerebral activation associated with the subject's native language (L1) compared with a second language (L2). In a recent PET investigation on bilingualism we showed that auditory processing of stories in L1 (Italian) engages the temporal lobes and temporoparietal cortex more extensively than L2 (English). However, in that study the Italian subjects learned L2 late and attained a fair, but not an excellent command of this language (low proficiency, late acquisition bilinguals). Thus, the different patterns of activation could be ascribed either to age of acquisition or to proficiency level. In the current study we use a similar paradigm to evaluate the effect of early and late acquisition of L2 in highly proficient bilinguals. We studied a group of Italian-English bilinguals who acquired L2 after the age of 10 years (high proficiency, late acquisition bilinguals) and a group of Spanish-Catalan bilinguals who acquired L2 before the age of 4 years (high proficiency, early acquisition bilinguals). The differing cortical responses we had observed when low proficiency volunteers listened to stories in L1 and L2 were not found in either of the high proficiency groups in this study. Several brain areas, similar to those observed for L1 in low proficiency bilinguals, were activated by L2. These findings suggest that, at least for pairs of L1 and L2 languages that are fairly close, attained proficiency is more important than age of acquisition as a determinant of the cortical representation of L2.

Perceptual adjustment to time-compressed speech: a cross-linguistic study.

Previous research has shown that, when hearers listen to artificially speeded speech, their performance improves over the course of 10-15 sentences, as if their perceptual system was "adapting" to these fast rates of speech. In this paper, we further investigate the mechanisms that are responsible for such effects. In Experiment 1, we report that, for bilingual speakers of Catalan and Spanish, exposure to compressed sentences in either language improves performance on sentences in the other language. Experiment 2 reports that Catalan/Spanish transfer of performance occurs even in monolingual speakers of Spanish who do not understand Catalan. In Experiment 3, we study another pair of languages--namely, English and French--and report no transfer of adaptation between these two languages for English-French bilinguals. Experiment 4, with monolingual English speakers, assesses transfer of adaptation from French, Dutch, and English toward English. Here we find that there is no adaptation from French and intermediate adaptation from Dutch. We discuss the locus of the adaptation to compressed speech and relate our findings to other cross-linguistic studies in speech perception.

Language discrimination by newborns: toward an understanding of the role of rhythm.

Three experiments investigated the ability of French newborns to discriminate between sets of sentences in different foreign languages. The sentences were low-pass filtered to reduce segmental information while sparing prosodic information. Infants discriminated between stress-timed English and mora-timed Japanese (Experiment 1) but failed to discriminate between stress-timed English and stress-timed Dutch (Experiment 2). In Experiment 3, infants heard different combinations of sentences from English, Dutch, Spanish, and Italian. Discrimination was observed only when English and Dutch sentences were contrasted with Spanish and Italian sentences. These results suggest that newborns use prosodic and, more specifically, rhythmic information to classify utterances into broad language classes defined according to global rhythmic properties. Implications of this for the acquisition of the rhythmic properties of the native language are discussed.

Language-specific listening.

Languages differ in their phonological structure and physcholinguists have begun to explore the conseqence, of this fact for speech perception. We review research documenting that listeners attune their perceptual processes finaly to exploit the phonological regularities of their nativ language. As a consequence, these perceptual process are fill-adapted to listening to languages that do not display such, regularities. Thus, not only do late language-learners have trouble speaking a second language, also they do not hear it as native speakers do; worse, they apply their native language listening prosedures which may actually interfere with successful processing of the non-native input. We also present data from studies on infants showing that the initial attuning occurs early in life; very yong infants are sensitive to the relevant phonological regularities which distinguish different languages, and quickly distinguish the native language of their environment from languages with different regularities.

Anatomical variability in the cortical representation of first and second language.

Functional magnetic resonance imaging was used to assess inter-subject variability in the cortical representation of language comprehension processes. Moderately fluent French-English bilinguals were scanned while they listened to stories in their first language (L1 = French) or in a second language (L2 = English) acquired at school after the age of seven. In all subjects, listening to L1 always activated a similar set of areas in the left temporal lobe, clustered along the left superior temporal sulcus. Listening to L2, however, activated a highly variable network of left and right temporal and frontal areas, sometimes restricted only to right-hemispheric regions. These results support the hypothesis that first language acquisition relies on a dedicated left-hemispheric cerebral network, while late second language acquisition is not necessarily associated with a reproducible biological substrate. The postulated contribution of the right hemisphere to L2 comprehension is found to hold only on average, individual subjects varying from complete right lateralization to standard left lateralization for L2.