Retrospective and prospective coding for predicted reward in the sensory thalamus.

Reward is important for shaping goal-directed behaviour. After stimulus-reward associative learning, an organism can assess the motivational value of the incoming stimuli on the basis of past experience (retrospective processing), and predict forthcoming rewarding events (prospective processing). The traditional role of the sensory thalamus is to relay current sensory information to cortex. Here we find that non-primary thalamic neurons respond to reward-related events in two ways. The early, phasic responses occurred shortly after the onset of the stimuli and depended on the sensory modality. Their magnitudes resisted extinction and correlated with the learning experience. The late responses gradually increased during the cue and delay periods, and peaked just before delivery of the reward. These responses were independent of sensory modality and were modulated by the value and timing of the reward. These observations provide new evidence that single thalamic neurons can code for the acquired significance of sensory stimuli in the early responses (retrospective coding) and predict upcoming reward value in the late responses (prospective coding).

[A case of 19th year pulmonary metastasis after radical mastectomy for breast cancer].

A 72-year-old woman was admitted to our hospital for further evaluation of a abnormal shadow in left middle lung field. The patient had undergone right mastectomy for infiltrating ductal carcinoma 19 years ago. She had no symptom, but had a time of mass X-ray screening this year. Chest CT finding showed a nodule 2 cm in diameter with slight irregular margin in S6 of left lung. We couldn't determine preoperatively that this tumor was a metastatic lesion or a primary lung cancer. And first, tumor was taken out for intraoperative frozen section diagnosis. Pathologist didn't diagnose whether this tumor was a metastatic or primary. So, we performed left lower lobectomy and mediastinal lymphadenectomy. On postoperative histopathologic finding lung cancer resembled well previous breast cancer. In immunohistochemical study cancer cells from lung and breast of the patient were respectively positive for anti Estrogen Receptor (ER) and anti Gross Cystic Disease Fluid Protein-15 (GCDFP-15). In conclusion lung cancer was diagnosed as a metastatic lesion from breast cancer 19 years ago. The patient has been well 2 years postoperatively without recurrence. In this case immunohistochemical examination was very useful for differentiation metastatic lesion and primary one.

[Clinicopathological studies of small-sized advanced large bowel cancer less than 2 cm in diameter].

The small sized lesion of the large bowel advanced cancer has been noticed in the development of the large bowel cancer. In this study, 17 lesions of the large bowel advanced cancer within less than 2 cm in diameter were studied clinicopathologically and histologically, according with PG(polypoid growth), NPG(non polypoid growth) classification and the subclassification of NPG, in which NPG-1 was defined that the height of the adjacent mucosa to the carcinomatous lesion was taller than that of the cancerous lesion, and the NPG except for NPG-1 was defined as NPG-2. And all of 17 lesions were NPG type(NPG-1:9 lesions, NPG-2:8 lesions). The results revealed that NPG-1 lesions were significantly smaller in maximum diameter, the invasion depth of its were deeper, these degree of venous invasion were higher and these carcinomatous differentiation were lower, comparing with those of NPG-2 lesions. In conclusion, it was indicated that the NPG-1 lesion was the large bowel advanced cancer which deeply invaded at the small-sized condition.

[A case of pulmonary dirofilariasis].

A 58-year-old man was admitted to our hospital for detailed examination of continuous cough. On a chest X-ray film, abnormal shadow was detected in the right lower lung field. Preoperative examination findings didn't lead to a definitive diagnosis. Under thoracoscopy partial resection of the lung was performed to rule out a malignant lesion. Intraoperative pathologic finding revealed a granulomatous lesion. And, final pathological diagnosis showed to be a pulmonary dirofilariasis. His postoperative course was not eventful. On 20 th day he discharged postoperatively. Now, under the Pet-boom the disease has been reported increasingly. But it is difficult to find the disease preoperatively. So, it is real to be operated for differentiate from a malignant lesion. Recently in many cases open lung biopsy, has been undergone with less invasive procedure such as thoracoscopy and VATS. It will be mainstream in future.

[A case of arteriovenous fistula of the lung].

A 29-year-old male was admitted to our hospital for further evaluation of left sided paresis, cyanosis, clubbing finger. The laboratory data revealed polycythemia and hypoxemia. Cerebralarteriogram showed right middle cerebral artery occulusion. Cardiofunctional test showed atrial fibrillation, lower left ventricular function. Cardiac catheterization, pulmonary arteriography and three dimensions CT were performed. Right to left shunt rate was 20.4%. A single large pulmonary arteriovenous fistura with a feeding artery (A10) and a draining vein (V10) was found clearly. In this cases, arteriovenous fistula was large, blood flow was thought to be rapid. We thought transcatheter embolization was not useful. And we performed right lower lobectomy. Postoperative course was not eventful. Cyanosis disappeared, clubbing finger was cured.

ABR and temporal bone pathology in Hurler's disease.

This is believed to be the first report on estimating hearing loss in Hurler's disease, based on the correlation between ABR and temporal bone pathology. ABR findings revealed hearing loss to be about 70 dB or more as result of peripheral mixed impairment. A histological study of the temporal bones revealed almost all pathological findings in the conductive system, except for the hyperplastic arachnoid in the internal auditory canal. In the middle ear cavity, otitis media, residual mesenchyme and deformity of ossicles were found. We explain the conductive component to be due to otitis media and poor ossicular connection. However, the etiology of the sensorineural component remains speculative. In Hurler's disease, hearing loss with mental retardation is often found at infantile age. Therefore, assessing the extent of hearing loss exactly was difficult, for example, the severity. the etiology and incidence of sensorineural impairment. We emphasize the need for not only well-described pathological studies but also for more objective functional investigations, at least ABR.

Pretreatment with topical 60% lidocaine tape reduces pain on injection of propofol.

UNLABELLED: We determined whether pretreatment with topical 60% lidocaine tape reduced the incidence of pain on injection of propofol compared with mixing intravenous lidocaine with propofol. In a randomized, double-blind trial, 90 patients were allocated to one of three groups: pretreatment with a bioocclusive dressing and administration of a premixed solution of propofol 180 mg and 2 mL of normal saline (Group A); pretreatment with 60% lidocaine tape and a premixed solution of propofol and normal saline (Group B); or pretreatment with a bioocclusive dressing and a premixed solution of propofol 180 mg and lidocaine 40 mg (Group C). The incidences of pain in Groups A, B, and C were 86.7%, 33.4%, and 20%, respectively. Group B and Group C had a significantly lower incidence of pain than Group A. There was no significant difference in the incidence of pain between Group B and Group C. There was no significant difference in the distribution of site of pain on injection of propofol among the three groups. Pretreatment with topical 60% lidocaine tape reduced the incidence of pain on injection of propofol similar to that of intravenous lidocaine mixed with propofol. IMPLICATIONS: Pretreatment with topical 60% lidocaine tape reduces the pain associated with injection of propofol, a frequently used intravenous anesthetic. This approach should increase patient comfort during induction of anesthesia.

Noise in aerobic facilities.

Noise levels were evaluated before and during aerobic sessions in 3 aerobic studios. In addition, hearing threshold levels (HTLs) of 10 female aerobic instructors with the mean (+/- SD) ages of 25.4 (+/- 2.4) years were measured before and 2 min after an aerobic session. The mean (+/- SD) of total instruction time of these subjects was 1274.0 (+/- 704.9) h. Before the aerobic session, noise level was 63 dB(A) and increased to 87 dB(A) during a warm-up period. The highest noise levels of 93-96 dB(A) were recorded during a peak exercise period and decreased to 73 dB(A) during a cool-down period. The dominant spectra of sound pressure levels (SPLs) during the aerobic session were in the frequency range of 1-2 kHz at levels of 75-88 dB(C). The mean values of HTL obtained for each ear of these subjects were between 5 and 15 dB in the frequency range of 1-8 kHz. No significant differences in the mean HTLs of pre- and post-aerobic sessions could be obtained. The mean values of HTL of two groups of subjects divided by their total instruction time (n = 5 in each group, and p < 0.01 in their total instruction time) were quite comparable.

Prevalence of Raynaud's phenomenon in different groups of workers operating hand-held vibrating tools.

In eight groups of subjects operating various hand-held vibrating tools and aged from 30 to 59 years, the prevalence rates of vibration-induced white finger (VWF) and numbness, pain, or stiffness in the upper and lower extremities were investigated. Hand-transmitted vibration levels (HTVLs) were measured on the back of the hand, by means of unidirectional (x-axis) vibration dosimeters, and the frequency-weighted acceleration levels [(Lh,w)eq,t] were determined as the vibration levels. The prevalence rates of VWF and numbness of the hands in these subjects were compared to the prevalence rates of Raynaud's phenomenon (RP) and numbness of the hands in 1027 males and 1301 females not occupationally exposed to vibration (age range: 30-59 years). It was observed that in subjects exposed to HTVLs of between 1.1 and 2.5 m/s2, the prevalence of VWF was between 0.0% and 4.8%. The prevalence of VWF reached 9.6% in a group of workers exposed to HTVLs of 2.7-5.1 m/s2. The latter group showed a significant difference (P < 0.05) in the prevalence of VWF compared to the 2.7% prevalence of RP in male subjects of the general population. The prevalence of VWF in female subjects exposed to vibration (4.3%) was not significantly different from the prevalence of RP in females of the general population (3.4%). The prevalence rates of numbness of the hands were in the range of 6.5%-30.4% in the exposed groups and in the range of 13.4%-29.5% in the general population. Among the subjective symptoms, only VWF showed a significant positive correlation with HTVLs (R2 = 0.5, P < 0.05). It was concluded that in decisions concerning quantitative recommendations for vibration exposure, the prevalence of VWF should be employed. With a view to decreasing the risk of developing VWF, estimated vibration safety values for 4 h and 2 h daily exposures are discussed.

Prevalence of Raynaud's phenomenon and specific clinical signs related to progressive systemic sclerosis in the general population of Japan.

BACKGROUND: In order to evaluate the prevalence rates of Raynaud's phenomenon (RP) and specific clinical signs related to progressive systemic sclerosis (PSS) in the general population of Japan, inquiries were made concerning RP in the hands and dermatologic examinations were also conducted. METHODS: One thousand and sixty-three subjects (332 men and 731 women) over 30 years of age who underwent inhabitants' health examinations in 1990 were considered for this study. RESULTS: The prevalence of RP was 3.0% in men and 3.4% in women. In 8 men and 17 women with RP who received the blood tests, the positive rates of antinuclear antibody (ANA) were 12.5% and 35.3% in men and women, respectively. The prevalence rates of all five specific clinical signs related to PSS, sclerodactyly, pitting scars of the fingers, brown pigmentation of the body, shortened frenulum of the tongue, and flexion contracture of fingers, were under 2% in men and 3% in women. In women with RP the prevalence rates of sclerodactyly, pitting scars of the fingertips, brown pigmentation of the body, and shortened frenulum of the tongue were 16.0, 4.0, 4.0, and 16.0%, respectively. These values were significantly higher than those of persons without RP. CONCLUSIONS: Because some persons with primary RP may become typical cases of PSS within several years, a followup study, particularly for women who have positive titers of ANA with RP, should be carried out to find out whether the persons suffer from PSS or not.

[Postoperative pain relief by preanesthetic administration of buprenorphine suppository in elective mastectomy].

Seventy female patients scheduled for elective mastectomy were divided into three groups: Buprenorphine suppository (BPS) 0.4 mg group (n = 29); BPS 0.2 mg (n = 23) group; and control (scopolia extract and tannic acid suppository) group (n = 18). Suppositories were administered rectally to patients of each group one hour before induction of anesthesia. Plasma buprenorphine concentrations, sedation scores at entering the operating room, postoperative pain scores and side effects were evaluated. There were no significant differences in sedation effects of suppository among the three groups. Although there were significant differences in pain scores except at the time when patients left the operating room between BPS 0.2 mg group and the control group, postoperative pain relief in BPS 0.2 mg group was judged not enough. However, postoperative pain relief was more satisfactory in the BPS 0.4 mg group. Plasma concentrations of the BPS 0.4 mg group were higher than those of the BPS 0.2 mg group. Although nausea and vomiting were observed in 5 patients (17.2%) of the BPS 0.4 mg group and 4 patients (17.4%) of the BPS 0.2 mg group, respiratory depression and changes in blood pressure and heart rate were not observed in all groups. In conclusion, preanesthetic administration of the BPS 0.4 mg seemed to be useful for postoperative pain relief after elective mastectomy.

A survey on noise exposure level in an aluminum can production plant.

The present investigation was designed to quantify noise exposure of laborers at various sections of an aluminum can production plant. The acoustic environment in each area was described by sound pressure level (SPL). Decibel (dB) readings were taken for a range of individual frequencies and weighting scales (A and C). Speech interference level (SIL) values for laborers in different production sections were also determined. Moreover, by means of a personal noise dosimetry technique, the equivalent continuous noise exposure level (dB(A)) during an 8-h shift (Leq, 8) was computed. The results obtained were as follows. Spectral analysis of the noise indicated that high SPL associated with high frequency noise exceeded the permissible limit against hearing damage, and it generally amounted to levels higher than 90 dB(A), whereas those inside the control rooms were in the range of 54-60.5 dB(A). Assessment of the results obtained from personal noise dosimeters also revealed that the Leq,8 values were higher than the prescribed limit (85 dB(A)). By preliminary audiometric examinations on the right ears of workers, hearing threshold shifts (HTS) were noticed in the range of 7-11 dB at 1 kHz and 12-16 dB at 4 kHz. With regards to the SIL values (93.2-96.5 dB(A)) which were more than the maximum vocal effort, communication between workers and/or with supervisor were appraised to be very difficult (shouting) or impossible. It was concluded that (a) the dB readings observed in this survey indicate a potentially serious possibility of hearing disability, even though high level of HTS could not be noticed in the preliminary audiometric test, and (b) the risk of accidents should also be taken into account regarding the nonauditory effects of such a high level of noise. We suggest that (1) minimizing the transmission of noise through acoustical countermeasures need to be considered, and (2) introducing a schedule comprising on-time and off-time could be beneficial in a workers' health conservation program.

Cutaneous signs (Raynaud's phenomenon, sclerodactylia, and edema of the hands) and hand-arm vibration exposure.

Dermatological tests and examinations of the hand(s) were carried out in vibration-exposed and unexposed males. The subjects were 179 chain-saw workers in private forestry companies and 205 local inhabitants who had never used vibrating tools. The prevalences of Raynaud's phenomenon (RP), sclerodactylia, and edema of the hands were estimated in both groups, and associations between these cutaneous signs and vibration exposure were evaluated. The prevalences of RP and edema in the exposed group were 9.5% and 1.7%, respectively, and in the unexposed group, 2.9% and 1.5%, respectively. Sclerodactylia was seen in 31.8% of the chain-saw workers but in only 6.4% of the unexposed individuals. In statistical analyses based on unconditional logistic regression models with adjustment for age, RP was associated with long-term (> or = 20 years) vibration exposure [odds ratio (OR) = 7.06; 95% confidence interval (CI) = 2.51-19.87]. Sclerodactylia was associated with both short- and long-term vibration exposure (OR = 6.54, CI = 3.30-13.36; OR = 7.05; CI = 3.41-14.60, respectively). There were significant dose-response relationships between RP and duration of exposure and between sclerodactylia and duration of exposure. Results of function tests indicated a longer recovery time and a higher vibration threshold for the workers with RP. The presence of sclerodactylia, however, did not have any significant influence on function test results. It is possible to conclude that not only RP but also sclerodactylia could be induced by vibration exposure. However, most cases of sclerodactylia were not so serious as to involve disturbances of peripheral circulatory and nerve function.

[Differences in the prevalences of Raynaud's phenomenon in general populations living in a mountain area and in a plain area].

Raynaud's phenomenon (RP) which is the episodic and reversible vascular spasm of the extremities can be elicited by cold or emotional changes. RP has been classified into two groups. One is primary Raynaud's phenomenon (PRP) with no identifiable underlying disease and/or cause, and the other is the secondary form of RP (Raynaud's syndrome) with underlying disease and/or cause, e.g., collagen disease, trauma, vibration from vibrating tools, etc. In the present study using this definition of RP the prevalences of RP were studied in general populations in a mountain village "T" and in a town "K" located in a plain area in Gifu prefecture, Japan. The prevalences of RP in T Village were 8.0% (25/314) in males and 3.5% (16/454) in females, and in K Town 2.7% (7/259) in males and 3.2% (21/657) in females. In 52% of the male cases in T Village it was estimated that the exposure to vibration from vibrating tools was the cause of RP. In K Town no male cases of RP were induced by vibration. Exposure to vibration may be one of the important factors when prevalences of RP are investigated in various areas. There were no significant differences between the two areas in the prevalences of PRP (T Village: male 2.9%, female 3.1%; K Town: male 2.7%, female 2.9%). The annual mean air temperature was usually 5-6 degrees C lower in T Village than that in K Town. From the results of this study the differences in the mean air temperature did not appear to have a significant influence on the prevalence of PRP in each area.

[Health condition of female aerobic dance instructors. Subjective symptoms and related factors].

Aerobic dance has recently become popular in all age groups, but the injuries among full-time and part-time aerobic dance instructors have rarely been pointed out in Japan. In this study the subjective symptoms of 63 female instructors in Gifu area were evaluated through health questionnaire. As a control group, 94 female students of the same age group were also included to compare the prevalence of subjective symptoms. Multiple logistic regression analysis was applied to observe the relation between instructors' symptoms and working conditions. The following results were obtained: 1) Complaints of leg and foot pain and laryngeal discomfort were significantly greater in instructors than in students even after adjusting for age and participation in other sports. 2) A significant positive relation was found in instructors between the frequency of dance lessons (times/wk) and various symptoms (calf pain, foot pain, sore throat, and hoarse voice) after adjusting for age and participation in other sports. These results suggest that leg and foot pain and laryngeal discomfort are characteristic symptoms of aerobic dance instructors. Consideration should be made to adjust the frequency of dance lessons in order to reduce these symptoms.

Noise exposure level while operating electronic arcade games as a leisure time activity.

In order to study noise levels associated with electronic arcade games, noise measurements were made in 3 selected game centers and 192 samples were taken in each location. The background noise was recorded at a level of 61 dB(A) and 64 dB(C). When the electronic games were performed these levels of noise reached to 88 approximately 90 dB(A). The 1/3 octave bands analyzing sound pressure levels showed that more intense noise levels arose in a frequency range between 0.5 and 2.0 kHz. The computed values for noise pollution levels (LNP) and L90 (fast response A-weighted sound level exceeded 90% of the measurement time) ranged from 93.3 to 96.6 and from 85.1 to 87.3 dB(A), respectively. Concerning our results and according to Melnic (1979), it was estimated that these levels of noise might cause 4-8 dB temporary threshold shift (TTS) at 4.0 kHz in an individual with less than one hour of exposure to such a level of noise. As for the employees of the 3 game centers, the 8-hr equivalent continuous sound levels (Leq,8) were in the range of 80.3 approximately 87.5 dB(A), although their exposure time could not be exactly determined. It was suggested that: 1) The maximum levels should be limited to a reasonable level, either by the manufacturers or by the game center owners; 2) Education programs in industry should inform the employees about other factors outside the work that may affect their hearing; and 3) For policy-making on hearing conservation, recreational warning and standards should be established.

Hand-arm vibration syndrome and its prevalence in the present status of private forestry enterprises in Japan.

Currently there are no limitations on age of employment on private forestries in Japan. Hence, it was hypothesized that in these kind of enterprises, elderly chain saw operators, or those with long-term exposure, might be at higher risk of developing hand-arm vibration syndrome (HAVS). We consequently investigated the prevalence of HAVS in 447 chain saw workers on private forestries in Gifu Prefecture, Japan, with particular reference to age and exposure period. Of this population, 43 (9.6%) had signs and symptoms of vibration-induced white finger (VWF), and among these workers the severity of finger blanching was significantly correlated (P less than 0.01) with the exposure period. Classification of all subjects by exposure period showed that workers with greater than or equal to 30 years' exposure had higher prevalences of VWF (20.9%) and numbness of the hands (25.4%) compared to other groups. Significant differences (P less than 0.01) were found between the functional capacities of workers with VWF and those of control subjects. We concluded that (a) the elderly chain saw operators and those with longer exposure should be moved to other jobs with a lower or no risk of exposure to vibration, and (b) the results of screening tests, even without cold water immersion (which we did not employ, in order to protect workers' hands), could be helpful for the identification of workers with VWF.

[Changes of peripheral blood parameters in aerobic dance instructors after aerobic dance instruction].

To investigate the biological load of aerobic dance instruction on the body, a blood biological study was performed on 13 female instructors. The values were compared with 10 female healthy controls. The results obtained were as follows. 1. A significant negative correlation was observed between the total experience of aerobic dancing (in years) and the levels of serum phospholipids. In addition, the numbers of white blood cells and the levels of serum phospholipids, lipoperoxide, uric acid and creatinine were significantly related to aerobic dance instruction time (years). 2. The levels of serum CPK, aldolase, GOT, BUN and creatinine in the aerobic dance instructors were significantly higher than those in the controls. 3. The levels of serum CPK, uric acid, BUN, creatinine and Ca increased significantly after an intermediate class lesson (about 60 minutes). In addition, the numbers of white blood cells also increased after the lesson, but not significantly. Moreover, Significant decreases of the mean corpuscular volume and serum Mg were observed after the lesson.