Emotional Value of Fear Memory and the Role of the Ventral Hippocampus in Systems Consolidation.

Recent studies have explored the circuitry involving the ventral hippocampus (vHPC), the amygdala, and the prefrontal cortex, a pathway mainly activated to store contextual information efficiently. Lesions in the vHPC impair remote memory, but not in the short term. However, how the vHPC is affected by distinct memory strength or its role in systems consolidation has not yet been elucidated. Here, we investigated how distinct training intensities, with strong or weak contextual fear conditioning, affect activation of the dorsal hippocampus (dHPC) and the vHPC. We found that the time course of memory consolidation differs in fear memories of different training intensities in both the dHPC and vHPC. Our results also indicate that memory generalization happens alongside greater activation of the vHPC, and these processes occur faster with stronger fear memories. The vHPC is required for the expression of remote fear memory and may control contextual fear generalization, a view corroborated by the fact that inactivation of the vHPC suppresses generalized fear expression, making memory more precise again. Systems consolidation occurs concomitantly with greater activation of the vHPC, which is accelerated in stronger fear memories. These findings lead us to propose that greater activation of the vHPC could be used as a marker for memory generalization.

Mechanistic and spectroscopic identification of initial reaction intermediates for prenal decomposition on a platinum model catalyst.

The prediction of a reaction mechanism and the identification of the corresponding chemical intermediates is a major challenge in surface science and heterogeneous catalysis, due to a complex network of elementary steps and surface species. Here we demonstrate how to overcome this difficulty by tracking the temperature dependent formation of the initial reaction intermediates and identifying the decomposition pathways in the case of prenal, an α,ß-unsaturated aldehyde, on the Pt(111) model catalyst surface by combining vibrational spectroscopy, thermal reaction/desorption spectroscopy (TPRS) experiments and detailed theoretical analysis. TPRS characterization of this reaction up to 600 K shows a series of desorption states of H(2) (∼280 K, 410 K and 473 K) and CO (∼414 K), giving valuable insights into the sequence of elementary steps suggesting that the loss of hydrogen and the carbonyl functions are among the first elementary steps. HREELS experiments recorded after annealing to specific temperatures result in complex spectra, which can be assigned to several subsequently formed and transformed surface intermediates. Starting from stable prenal adsorption structures, complementary DFT calculations allow the determination of the most likely reaction pathway for the initial decomposition steps and the identification of the corresponding intermediates by comparison with HREELS. The decomposition occurs from the strongly bonded prenal adsorption structures via a dehydro-η(3)-triσ(CCC)-H1 intermediate to the highly stable η(1)-isobutylidyne species at high temperatures.

Translocation t(11;19)(q21;p13.1) as the sole chromosome abnormality in a cystadenolymphoma (Warthin's tumor) of the parotid gland.

Cytogenetic findings on a cystadenolymphoma (Warthin's tumor) of the parotid gland are reported. In the primary culture, a reciprocal balanced translocation t(11;19)(q21;p13.1) as the sole clonal abnormality was found in the majority of metaphases. At this time, the proliferation of epithelial cells was observed in the cultures. Later passages showed overgrowing fibroblasts, and the abnormal metaphases disappeared. This result should stimulate further efforts for cytogenetic investigations of the epithelial part and permit a better understanding of the histogenesis of this particular tumor.

Cytogenetic subtyping of 220 salivary gland pleomorphic adenomas: correlation to occurrence, histological subtype, and in vitro cellular behavior.

Based on the hypothesis that three main cytogenetic subtypes of salivary gland pleomorphic adenomas can be distinguished which may also represent different etiologic entities, we investigated whether these subtypes correspond to clinical, histologic, or biologic features of 220 tumors karyotyped (including 117 tumors with detailed clinical history and histologic subtyping). The following results were obtained. As compared with the group of patients showing salivary gland pleomorphic adenomas with an apparently normal karyotype, the patients in the "8q12-group" were significantly younger (51.1 years versus 39.3 years, p < 0.001). The distribution of histologic subtypes also showed highly significant differences between the groups. Whereas the breakpoint in the 8q12 group was always mapped to a single band, no exact localization of the breakpoint in the group of tumors showing chromosome number 12 abnormalities was possible. In most cases, however, the breakpoints were clustered to 12q15. Finally, all tumors with 8q12 breakpoints showed a characteristic in vitro cellular morphology which was also observed in a few tumors with an apparently normal karyotype but in none of the tumors with the 12q13-15 breakpoint.

Detection and quantitation of intermittent CSF rhinorrhea during prolonged cisternography with 111In-DTPA.

In an attempt to improve the diagnosis and to assess the intensity of intermittent cerebrospinal fluid rhinorrhea, indium-111 uptake by nasal pledgets during prolonged cisternography using 111In-DTPA was determined. In 12 patients having suspected cerebrospinal fluid rhinorrhea, cisternograms with calculation of counts/pixel in regions of interest were obtained, blood samples drawn, and nasal pledgets placed several times during 48 or 72 hr after lumbar intrathecal administration of 111In-DTPA. In three patients intermittent cerebrospinal fluid rhinorrhea was thus revealed; study by computed tomography was negative in each case. This procedure of extended radionuclide cisternography helped to detect, localize, and quantify intermittent cerebrospinal fluid rhinorrhea so that therapeutic decisions were facilitated and surgical intervention was minimized.

Therapy of parotid tumors. / Zur Therapie von Parotistumoren.

A therapy schedule is presented for the surgical treatment of parotid tumors, based on the experience gained from more than 600 operations for parotid tumors. The individual surgical techniques (lateral parotidectomy, total parotidectomy with preservation or resection of the facial nerve, with or without reconstruction of the nerve) are selected depending on the histologic findings in the tumors. The fact is stressed that in a tumor disease the lateral parotidectomy constitutes the minimal operation. The different tumors can be divided into four groups. The operative treatment of tumors of the facial nerve in its extratemporal course is particularly mentioned since clinically these growths usually appear to be parotid tumors.

Reactivation enables memory updating, precision-keeping and strengthening: exploring the possible biological roles of reconsolidation.

Although much has been learned regarding the molecular and cellular mechanisms of memory reconsolidation, its actual biological function remains unclear. In this work we investigate the possibility that three different mnemonic processes - updating, precision-keeping and trace strengthening - are mediated by reconsolidation in contextual fear conditioning. Reconsolidation involves the activation of calcium channels for the destabilization during the reactivation. Our results show that when memory is reactivated in a situation that does not match the original information, content is modified, i.e., "updated". However, when the contextual condition matches the original one, memory reactivation contributes either to its strengthening or to the maintenance of its precision content over time. Since the L-type voltage-gated calcium channel antagonist nimodipine blocked these effects, we suggest that reconsolidation is the mechanism supporting these processes.

[Animal experiment histological-histochemical studies on the development of hearing disorders related to hypothyroidism]. / Tierexperimentelle histologisch-histochemische Untersuchingen zur Formalgenese der hypothyreotisch bedingten Schwerhörigkeit

It has been known for a long time that hearing deficits may coexist in patients with thyroid disease, but without definite morphologic evidence present to correlate gland dysfunction with hearing disturbances. To clarify this relationship between thyroid dysfunction and hearing disturbances, the guinea pig was employed as an experimental model. 70 animals were thyroidectomized, and maintained in a hypothyroid state for varying periods of time. The animals were then sacrificed, and various histochemical studies then performed. These studies included analysis for glycosidase (beta-galactosidase, beta-glucuronidase, n-acetyl-beta-glucosamide), non-specific esterases, sulfatases, sulghydryl groups as well as mucous substances within the cochlea and saccus endolymphaticus of the experimental animals. Results indicated that hyaluronidase-sensitive mucous substances were increased in the scala of the inner ear. As a consequence of increased deposition of acid mucopolysaccharides, the relationship of potassium to sodium in endolymph and perilymph was found markedly altered. Marked swelling of the chambers of the inner ear was noted, and believed to represent hydropic induction by acid mucopolysaccharide-with consequent alteration of electrolyte relationships ("Electrochemical Theory").

[Surgery of injuries of the facial nerve on the lateral region of the face (author's transl)]. / Die Versorgung der Verletzungen des Nervus facialis in der lateralen Gesichtsregion

Injuries of the lateral facial region frequently cause a partial or complete destruction of the trunk or individual branches of the facial nerve. Operative methods are presented, which have proved to be especially successful for reconstruction of the facial nerve. For a successful outcome of the nerve suture together with a good functional result later on, an exact suture tehcnique is mandatory. The procedure is discussed. On the other hand, the indication for operation raises a number of problems, which mainly concern the extent of nerve injury and the period elapsed after the damage.

[Differential diagnosis of salivary gland swellings (excluding neoplasms)--the ORL view (author's transl)]. / Differentialdiagnose der Wangenschwellungen (ausschliesslich der Speicheldrüsen-Tumoren)--aus der Sicht des HNO-Arztes.

Important investigatory methods for the diagnosis of non-neoplastic salivary gland disease are discussed. The difficulties found with these different methods are emphasized, and biopsy is recommended as the most reliable means for diagnosis. Some salivary gland disorders are caused by hypotensive drugs. Chronic recurrent parotitis is presented as an example of the difficulties in differential diagnosis and treatment.

Etiology and pathogenesis of the inflammatory diseases of the cephalic salivary glands.

The complexity of the inflammatory pathological processes in the salivary glands, especially in the parotid gland, requires subtle diagnostic techniques. A multitude of clinical, pathological and anatomical as well as laboratory investigation methods are now available. This permits to make a safe diagnosis in most cases. However, many questions concerning etiology and pathogenesis of the inflammatory diseases of the cephalic salivary glands remain unanswered. This impedes a specifically directed therapy with will have to be the aim of further clinical and theoretical research.

[Clinical aspects of non-tumorous diseases of the salivary glands]. / Klinik der nichttumorbedingten Erkrankungen der Speicheldrüsen.

The vast field encompassed by the non-tumorous diseases of the salivary glands poses difficult problems for their diagnosis and therapy. In order to facilitate comprehension of the pathological processes and the therapeutical possibilities for their treatment, physiological and biochemical aspects of salivary gland function are presented in the introduction. There are also mentioned in detail most of the diagnostic methods clinically applied today and stress is laid on their respective diagnostic values. In contrast to the opinion of many authors, exploratory excision and puncture are shown to be very important diagnostic tools in salivary gland pathology. The specific application of these methods is often the only means for a reliable diagnosis. The classification of the diseases follows Seifert's (1971) proposal. The chronic diseases of the salivary glands are specifically mentioned with the chronic recurrent and the chronic myoepithelial sialoadenitis taking first place. The sialoses are presented in a larger chapter. An attempt was made to correlate clinical and experimental results, to establish working hypotheses concerning the development of sialoses, to suggest therapeutical possibilities and, last not least, to give an idea of the many clinical and patho-anatomical difficulties to be overcome for a satisfactory understanding of such pathological processes. Finally, various forms of salivary gland fistulas and their treatment are mentioned. The long list of references merely gives an approximation of the abundance of publications dealing with the problems of this field.

[Penicillin levels in tonsillar tissue and serum after intramuscular and oral application (author's transl)]. / Antibiotikaspiegel im Tonsillengewebe und Serum nach intramuskulären und oralen Penicillingaben

Penicillin levels were determined in both serum and tonsillar tissue 1-2 h (29 patients) and 3-4 h (16 patients) after intramuscular application of Penicillin-G resp. oral doses of Penicillin-V. All tonsils were found to contain different amounts of Penicillin. Concentrations of antibiotic in the tonsillar tissues are dependent on the respective serum levels. The serum-tonsil-difference of the Penicillin levels increases significantly in adults. The efficiency of oral and intramuscular Penicillin application and the occasionally described failure of oral Penicillin medication are discussed with regard to the minimal inhibitory concentrations (MIC) for group A streptococci.

[Vasomotor rhinitis: a side-effect of hormonal contraception? (author's transl)]. / Vasomotorische Rhinitis. Eine Nebenwirkung hormonaler Kontrazeption

In order to detect a possible influence of hormonal contraception on the development of vasomotor rhinitis, a five-months rhinoscopic survey was conducted on 460 women whose ages ranged from 18 to 40 years. 67 (32.7%) of the 205 women taking oral contraceptives, and 77 (30.2%) of a control group of 255 women were found to have vasomotor rhinitis. A questionaire was used in the survey, and included the following items: contraceptive preparation used, duration of use, and nasal distress associated with medication or prior pregnancies. In contrast to the findings of other authors, it was not possible to correlate the development of vasomotor rhinitis with the administration of oral contraceptives during the present study. Moreover, results were not altered by taking into account the composition of the different contraceptive drugs used. The statistical significance of the present study was established by the comparison of findings with a randomly selected control group of patients during the same period of time.

[Value of needle biopsy for the diagnosis of salivary gland tumors]. / Stellenwert der Punktionszytologie in der Diagnostik der Speicheldrüsentumoren.

Tumors of the salivary glands can be diagnosed preoperatively by fine needle aspiration biopsy. Aspiration biopsy was performed in 328 cases with swelling of a salivary gland. Histologic findings were available for comparison in 186 cases. The cytologic reports yielded a positive tumor diagnosis in 84% of the cases with histologically verified tumors. False negative reports were mainly due to cystic tumors. Information concerning the dignity of the tumor was obtained in 95% of the cases recognized by cytology. The type of the tumor was correctly diagnosed in 90%.

[Aspiration biopsy cytology of salivary gland tumours (author's transl)]. / Punktionszytologie von Speicheldrüsentumoren.

Tumours of the salivary glands can be diagnosed in most cases by fine needle aspiration biopsy followed by cytological investigation of the biopsy samples. Compared with the histological results obtained from 194 samples, the diagnostic accuracy amounted to 75.5%. When the assessment of dignity of the tumour is carried out without further classification of the tumour, the accuracy increases above 90%. Possible errors involved in the aspiration technique and in the cytological assessment are discussed. The advantages of the fine needle aspiration biopsy for diagnosis and therapy of salivary gland tumours are stressed.

A causal relationship between chromosomal rearrangements and the genesis of salivary gland pleomorphic adenomas.

The results of chromosome analyses performed on 50 pleomorphic salivary gland adenomas in Germany are summarized herein and compared with those obtained on 100 adenomas studied in Sweden. In both series, characteristic or even specific structural chromosomal rearrangements involving either chromosome 8 or 12 were found that allowed the cytogeneticist to distinguish between subgroups. However, the significantly higher percentage of tumors with chromosome abnormalities in the adenomas examined in Germany is particularly noteworthy. In the near future, cytogenetic investigations together with molecular methods will allow investigators to describe basic mechanisms for the development of pleomorphic adenomas in terms of oncogenetics.

Rearrangements of chromosome region 12q13----q15 in pleomorphic adenomas of the human salivary gland (PSA).

Nine of 40 pleomorphic salivary gland adenomas (PSAs) showed clonal aberrations of chromosome 12, with a breakpoint at 12q13----q15. The cytogenetic findings in these cases and those of nine additional cases reported in the literature suggest that this type of aberration is a primary change directly involved in the genesis of PSA.