Volume 110  ·   Issue 10  ·  1997

OBJECTIVE To investigate the internal state of stress distribution in healthy human condyles and to offer some references for application of the temporomandibular joint (TMJ) biomechanics. METHODS Six male volunteers were selected to perform CT examination of the TMJ with 1.5 mm-thick sections at 1.5 mm intervals. Three dimensional image reconstruction of the joint was performed in the SUN workstation and the CT data were converted into the decimal system. The three dimensional finite element model mesh generation resulted from 1188 elements and 264 nodes in each condyle. Stress calculation was performed with SAP-V program, and the RESULTS were converted into mechanical density scalar. During the study, the internal state of stress distribution on each side condyle in every subject was analysed on the basis of loading on the anterior articular surface of the condyle. RESULTS Stress was concentrated in the anterior articular surface of the condyle and was highest at the loading point. The condylar cortical bone was the main load-bearing area. The level of stress distribution in the cancellous bone of the condyle was very low. Near condylar neck stress was well-distributed on the cortical. The internal state of stress was essentially symmetrical on the same cuts of both side condyles. CONCLUSIONS The results showed that three dimensional finite element analysis may indicate the internal state of stress distribution in the condyle, suggesting that a combination of the three dimensional finite element methods and the three dimensional imaging technique may be a useful means for diagnosis and treatment of TMJ diseases.

OBJECTIVE To study the regular pattern of growth and declination or the transmission potential of filariasis after the disease was basically (the microfilarial rate was lower than 1%) in Henan Province in 1987. METHODS According to the distribution of filaria species and original microfilarial rate, in 7 surveillance sites in 7 counties (cities) the etiology and mosquito vector surveys were carried out continuously during 1988-1995 and no control measurement for pathogen was taken. RESULTS Ten residual microfilaremias became negative gradually in the first 6 years and no new microfilaremias occurred during 1988-1995. During 1993 to 1995, the microfilaremias rate of population in the sites was 0. The natural infection rates of filarial larvae in vector mosquito were 0.1%-0. During the 8 years, 15 vector mosquitos were positive with a total of 18 filarial larvae which were all of first or second-stage larvae. The C. pipiens pallens was the main vector, the second was A. sinensis, with a small number of C. fatigans and A. anthropophagus. The man-biting rates of mosquitoes for outdoor sleepers fluctuated greatly, the highest one was 360.6 mosquitoes/person per night and the lowest, 7.2. The man-biting rates of mosquitoes for sleepers inside mosquito-net was about 1 mosquito/person per night. The proportion of multiparous mosquitoes also fluctuated more greatly, the highest one was 88.1% and the lowest 27.2% According to the data described above, the man-biting rate of vector mosquito which contained filarial L3 was 0. CONCLUSIONS The results suggested that after the microfilarial rate was lower than 1%, the residual microfilaremias became negative gradually in 3-6 years, and the transmission of the disease was blocked. Therefore, in the areas where filariasis was basically controlled, elimination of the disease was attainable within sight.

OBJECTIVE To study the developing cercaria of Schistosoma Japonicum (S. japonicum) on ultrastructural level by transmission electron microscope (TEM) for analyzing the morphological dynamic changes of the tegument, glands and musculature. METHODS Artificial infected Oncomelania hupensis were dissected under dissecting microscope and the daughter sporocysts picked up for studying the germinal cells stage (S1). The other embryonic cercaria were selected according to the modified parameter of Chen and Bier (1972). The specimens were prepared by conventional procedure of the laboratory of TEM and were observed by Hitachi H600. RESULTS Beside the germinal cell stage (S1), this is the first chronological study on the morphological development of S. japonicum cercaria from S2-S5 concerning the tegument and its elements (glycocalyx, sensory papilla, basal lamina and spine), head and acetabular gland and musculature of the body and tail. This article discusses the ultrastructural morphological differences from prior authors and emphasizes on the postacetalar gland and the pattern of tail musculature of the matured stage cercaria. CONCLUSIONS According to the cell division and differentiation, the process of development may be divided into 5 stages: S1, the single germinal cell stage; S2, the germinal ball stages: major multiplication and minor differentiation; S3, tail budding embryonic stage, both active in multiplying and differentiating; S4, the pre-matured stage, major differentiation and minor multiplication; and S5, the fully matured stage (completing the differentiation).

OBJECTIVE To observe the changes of abdominal sonography and 2 biochemical indicators for hepatic fibrosis before and after treatment with praziquantel in schistosomiasis japonica patients. METHODS Fifty-five persons infected with Schistosoma japonicum and treated with praziquantel were examined with ultrasonography and serum hyaluronic acid (HA) and type III procollagen (PC III) before and 1 year after treatment, and their data were compared with those in 55 normal controls. RESULTS With comparison of the data before praziquantel treatment, the length of the left liver lobe and the spleen in 55 patients all decreased (P<0.01) 1 year after treatment. No significant change was seen in interior diameter (d) of the portal vein, while a decrease in the ratio of the exterior diameter (D) and interior diameter of the second branch of the portal vein was very significant (P<0.01). Compared with the data in normal control, significantly higher levels in the thickness of the left lobe, the maximum oblique diameter of the right lobe, the length of the spleen, spleen index, the interior diameter of the portal vein and D/d ratio were seen in the patients both before and after treatment. The abnormal rate of the 2 serum parameters for hepatic fibrosis decreased significantly after treatment. CONCLUSIONS Parameters of hepatic fibrosis either by ultrasonography or by the 2 biochemical tests showed a significant improvement in 55 patients 1 year after treatment, although some of the indices did not yet return to normal levels.

OBJECTIVE To obtain information on prescription pattern of antipsychotic drugs for schizophrenic in-patients treated in public hospitals in Hong Kong. Four main areas of antipsychotic treatment are reported in this paper: (1) doses of antipsychotic drugs, (2) the practice of giving multiple antipsychotic agents simultaneously, (3) use of antipsychotics in divided daily doses and (4) co-administration of antipsychotic and antiparkinson drugs. METHODS A cross-sectional survey of prescriptions of antipsychotic medication for a representative sample of 957 schizophrenic in-patients was conducted on a randomly chosen census day. Questionnaire items included basic demographic and clinical data, as well as inventory for all medications received by patients on census day. RESULTS The mean antipsychotic dose was 854±759 (median: 600; range) 0-4450) mg CPZeq. Over two-third of the patients were given more than drug concurrently while less than 20% received the medication in multiple divided doses. Antiparkinson drugs were prescribed with antipsychotic medication in 69.61%, of the subjects. There were few differences between acute and chronic patients with respect to their respective prescription patterns. CONCLUSIONS Antipsychotic treatment of schizophrenic inpatients in Hong Kong is largely in accord with international standards. Problematic areas identified for closer scrutiny include the concurrent use of more than one antipsychotic drug for both acute and chronic patients, and the higher than recommended doses for antipsychotic drugs and frequent use of antiparkinson medication for chronic patients. Dissemination of these results, accompanied by continuing medical education about psychopharmacology, are planned to further improve the quality of treatment for schizophrenic patients.

OBJECTIVE To summarize the clinical features of 201 cases with Duane's retraction syndrome (DRS) and discuss its differential diagnosis. METHODS We retrospectively summarized the 201 cases from 1979 to 1996. The clinical features including chief complaints, sexual distribution, age at first visit, laterality, type of presentation, ocular deviation in the primary position, refractive errors, amblyopia, globe retraction, change of the palpebral fissure, upshoot and downshoot in adduction, binocular single vision, and its associated ocular and non-ocular anomalies were analysed. RESULTS There were 99 males and 102 females with a female-to-male ratio 1:1. The 65.88% of DRS cases had left eye involvement with two-to-one predilection for the left eye. The most common form of the syndrome was type I (184 patients, 91.54%). Exotropia was the most common deviation in the primary gaze (72 patients, 35.8%). Among 118 patients, most had abduction deficits, globe retraction in adduction, and faceturn as to maintaining single binocular vision. Crocodial tears (26 patients, 11.93%) was the most frequently encounted ocular abnormalities. CONCLUSIONS Diagnosis of DRS in a typical case is not difficult, however, children with bilateral abduction deficits which may mimic DRS must be differentiated from the following four motility disorders, namely, abducens nerve palsy, Moebius syndrome, congenital oculomotor apraxia, and congenital or infantile esotropia.

OBJECTIVE A human promyelocytic leukemia (APL) cell line NB4 was used to demonstrate the synergistic effects between all-trans retinoic acid (ATRA) and prostaglandin E2 (PGE2) on growth inhibition and cytodifferentiation induction. METHODS NB4 cells were cultured in the presence of either ATRA or PGE2 as a single agent or in combinations at various ratio. Cell growth was measured and myeloid differentiation was tested on consecutive days over the whole course of culture. RESULTS PGE2 and ATRA synergistically induced the myeloid differentiation of NB4 cells. In comparison with ATRA alone, the combination of PGE2 with ATRA caused an almost 20-fold decrease of effective concentration of ATRA. CONCLUSIONS The combination of ATRA and PGE2 at an appropriate ratio may provide a convenient oral regimen of combined differentiation therapy for a better clinical outcome in APL patients.

OBJECTIVE To evaluate a new scanning method designed for the diagnosis of early transtentorial hernia as compared with the routine scanning method (parallel to orbitomeatal line). METHODS 102 patients with unilateral high intracranial pressure and 100 volunteers without any cranial symptoms and signs were scanned on (1) the plane perpendicular to the plane of clivus and (2) the plane parallel to orbitomeatal line, a line joining the apex of the dorsum sellae and the lowest point of the clivus. RESULTS Vertical-to-clivus scanning method directly demonstrated the temporal transtentorial hernia in 48 of 102 patients with unilateral high intracranial pressure, but the orbitomeatal line scanning method was not able to show this direct finding. The projected tissue of the temporal lobe could be obviously shown and the degree of the hernia could be judged directly on the CT imaging with the vertical-to-clivus scanning method. Therefore, the CT diagnosis criterion of the hernia was suggested as follows: the hernia would be determined if the downward shift of the temporal lobe was more than 3 mm and suspected if less than 3 mm with ipsilateral high intracranial pressure. CONCLUSIONS This new method presented a superiority in showing the temporal transtentorial hernia for the patients with a cranial emergency.

OBJECTIVE To select advanced points from differently treated muscle grafts and explore a new conduit to bridge nerve defects. METHODS A total of 70 Sprague-Dawley rats were employed in this experiment. We applied a frozen probe to freeze the muscle in situ to disrupt any cellular elements of the local muscle grafts, but blood vessels to the muscle were carefully preserved. Radioactive microsphere technique was employed to visualize the blood supply to the muscle grafts. Immunohistochemical staining and ultrastructural observation were also carried out to assess the RESULTS of nerve regeneration. RESULTS The in-situ frozen muscle grafts were revascularized within the first 3 days, which led to fast migration of macrophages and Schwann cells. That was really reflected in the final results: the early incursion of regenerating axons, more regenerating axons at the early stage both in the grafts and distal stumps, and thicker myelin sheath of regenerating axons. CONCLUSIONS The in-situ frozen autogenous muscle graft is useful in the repair of sciatic nerve of rats. In the thicker and longer grafts the benefits will be more remarkable. It will be the most useful technique for nerve repair, especially in the repair of a large nerve gap in a poor recipient bed.

OBJECTIVE To determine the antoantibodies and anti-interferon antibody in chronic viral hepatitis patients treated with interferon and the relation of the antibodies to the curative effect of interferon. METHODS Forty chronic viral hepatitis patients (twenty cases for hepatitis B; twenty patients for hepatitis C) were studied. Indirect immunofluorescence assay (IFA) was used to measure the autoantibodies. Enzyme immunoassay (EIA) was used to measure the anti-interferon total antibody. RESULTS Compared with normal groups, the autoantibodies in patients increased significantly (P<0.01), and the anti-interferon antibody in chronic hepatitis B and hepatitis C patients had an obvious difference (P<0.05). As for the curative effect, the presence or absence of autoantibodies did not have a distinct significance in patients treated with alpha-interferon, but the patients with anti-interferon antibody before or after therapy might have a different response to alpha-interferon. CONCLUSIONS It was suggested that the presence of autoantibodies was not a contraindication to the use of interferon in patients with chronic viral hepatitis; the clinical significance of anti-interferon antibody should be further studied.