Unilateral high-riding vertebral artery is associated with asymmetric morphological changes of the atlantoaxial joint: a novel risk factor for atlantoaxial osteoarthritis

PURPOSE

This study aimed to investigate the association between unilateral high-riding vertebral artery (HRVA) and morphological changes in the atlantoaxial joint (AAJ) and to determine whether unilateral HRVA is a risk factor for atlantoaxial osteoarthritis (AAOA).

METHODS

We conducted a retrospective analysis of 2496 patients admitted to our medical center between January 2020 and December 2022 who underwent CT imaging of the cervical spine. Two hundred and seventy-two patients with unilateral HRVA (HRVA group) were identified and a respective 2:1 age- and sex-matched control group without HRVA was built. Morphological parameters, including C2 lateral mass settlement (C2 LMS), C1/2 coronal inclination (C1/2 CI), lateral atlanto-dental interval (LADI), and C1/2 relative rotation angle (C1/2 RRA) were measured. The degree of AAOA was recorded. Risk factors associated with AAOA were identified using univariate and multivariable logistic regression analyses.

RESULTS

The study included 61.4% women, and the overall average age of the study population was 48.7 years. The morphological parameters (C2 LMS, C1/2 CI, and LADI) in AAJ were asymmetric between the HRVA and the non-HRVA sides in the HRVA group (p < 0.001). These differences in parameters (d-C2 LMS, d-C1/2 CI, and d-LADI) between the HRVA and the non-HRVA sides, and C1/2 RRA were significantly larger than those in the control group. Eighty-three of 816 patients (10.2%) with AAOA had larger values of d-C2 LMS, d-C1/2 CI, d-LADI, and C1/2 RRA compared with the patients without AAOA (p < 0.05). The multivariable logistic regression analysis indicated that unilateral HRVA [adjusted odds ratio (OR) = 2.6, 95% CI: 1.1-6.3, p = 0.029], age in the sixth decade or older (adjusted OR = 30.2, 95% CI: 16.1-56.9, p < 0.001), women (adjusted OR = 2.1, 95% CI: 1.0-5.6, P = 0.034) were independent risk factors for AAOA.

CONCLUSION

Unilateral HRVA was associated with asymmetric morphological changes of nonuniform settlement of C2 lateral mass, lateral slip of atlas, and atlantoaxial rotation displacement. Besides age ≥ 60 years and females, unilateral HRVA is an independent risk factor for AAOA.

[The effect of Ba Duan Jin on the balance of community-dwelling older adults: a cluster randomized control trial]

Objective: To assess the effectiveness of a 6-month Ba Duan Jin exercise program in improving the balance of community-dwelling older adults. Methods: A two arms, parallel-group, cluster randomized controlled trial was conducted in 1 028 community residents aged 60-80 years in 40 communities in 5 provinces of China. Participants in the intervention group (20 communities, 523 people) received Ba Duan Jin exercise 5 days/week, 1 hour/day for 6 months, and three times of falls prevention health education, and the control group (20 communities, 505 people) received falls prevention health education same as the intervention group. The Berg balance scale (BBS) score was the leading outcome indicator, and the secondary outcome indicators included the length of time of standing on one foot (with eyes open and closed), standing in a tandem stance (with eyes open and closed), the closed circle test, and the timed up to test. Results: A total of 1 028 participants were included in the final analysis, including 731 women (71.11%) and 297 men (28.89%), and the age was (69.87±5.67) years. After the 3-month intervention, compared with the baseline data, the BBS score of the intervention group was significantly higher than the control group by 3.05 (95%CI: 2.23-3.88) points (P<0.001). After the 6-month intervention, compared with the baseline data, the BBS score of the intervention group was significantly higher than the control group by 4.70 (95%CI: 4.03-5.37) points (P<0.001). Ba Duan Jin showed significant improvement (P<0.05) in all secondary outcomes after 6 months of exercise in the intervention group compared with the control group. Conclusions: This study showed that Ba Duan Jin exercise can improve balance in community-dwelling older adults aged 60-80. The longer the exercise time, the better the improvement.

Predicting Treatment Response of Esophageal Cancer Treated by Concurrent Chemoradiotherapy Using Pre- and Posttreatment 18F-FDG PET Metabolic Characteristics

PURPOSE/OBJECTIVE(S)

This study hypothesizes that metabolic characteristics of esophageal tumors can be used to predict treatment response, which considers changes in the primary tumor and lymph nodes, for patients receiving neoadjuvant concurrent chemoradiotherapy (CCRT).

MATERIALS/METHODS

This study retrospectively included 60 esophageal cancer patients receiving CCRT followed by surgery. All patients received 18F-fluorodeoxyglucose positron emission tomography/computed tomography (FDG PET/CT) examinations prior to CCRT and in the interval between CCRT and surgery. On the pre-treatment FDG PET/CT images, the maximum standardized uptake value (SUVMaxPre) within the primary tumor was identified. By computerized methods, the CT images of pre- and post-treatment FDG PET/CT were registered. Then, the coordinates of SUVMaxPre were transformed to the post-treatment FDG PET images and delineated a sphere with a diameter of 5 cm to indicate the tumor position. After excluding air, the sphere was partitioned into several metabolic volumes by the optimal dichotomy of high and low metabolic FDG uptakes. Finally, the volume with the shortest distance to the center was adopted and represented by the maximum standardized uptakes (SUVMaxPost). Two additional features, SUVDiff and SUVDiffR, were defined as SUVMaxPost - SUVMaxPre and (SUVMaxPost - SUVMaxPre) / SUVMaxPre. Besides, for defining treatment response, the patients with and without residual tumors were defined as ypT+ and ESOCR based on the histopathology results of surgery. The ESOCR was further classified into pCR to indicate the absence of lymph node metastasis and LNM for remaining. Finally, the area under the receiver operating characteristic curve analysis (AUC) was conducted to assess the features' ability to differentiate two treatment responses. Kruskal-Wallis test was used to evaluate the differences in features between treatment responses.

RESULTS

Of the 60 patients, 55 were men (92%), and the mean age was 58. The number of tumors at the esophagus's upper, middle, and lower third were 8, 18, and 34, respectively. Ninety-eight percent of the tumors were squamous cell carcinomas (59/60). The patient numbers of ypT+ and ESOCR were 43 and 17 of which contained 13 pCR and 4 LNM. The SUVDiff and SUVDiffR exhibited a significant ability to identify the ESOCR with AUC = .337 (p = .05) and AUC = .290 (p = .012), respectively. In addition, a statistically significant difference was found among the three groups of ypT+, pCR, and LNM on SUVMaxPre (H = 6.252 and p = .044), SUVDiff (H = 7.948 and p = .019), and SUVDiffR (H = 8.405 and p = .015). In the post-hoc tests corrected by the Bonferroni, the difference between ypT+ and LNM was significant on these features.

CONCLUSION

The metabolic characteristics extracted from pre- and post-treatment FDG PET/CT images could indicate treatment response and disease progression. Further studies are warranted.

The association between unilateral high-riding vertebral artery and atlantoaxial joint morphology: a multi-slice spiral computed tomography study of 396 patients and a finite element analysis

BACKGROUND CONTEXT

A high-riding vertebral artery (HRVA) can deviate too medially, too posteriorly, or too superiorly to allow the safe insertion of screws. However, it is unknown whether the presence of a HRVA is associated with morphological changes of the atlantoaxial joint.

PURPOSE

To investigate the association between HRVA and atlantoaxial joint morphology in patients with and without HRVA.

STUDY DESIGN

A retrospective case-control study and finite element (FE) analysis.

PATIENT SAMPLE

A total of 396 patients with cervical spondylosis underwent multi-slice spiral computed tomography (MSCT) of cervical spine at our institutions from 2020 to 2022.

OUTCOME MEASURES

A series of atlantoaxial joint morphological parameters, including C2 lateral mass settlement (C2 LMS), C1-2 sagittal joint inclination (C1-2 SI), C1-2 coronal joint inclination (C1-2 CI), atlanto-dental interval (ADI), lateral atlanto-dental interval (LADI), and C1-2 relative rotation angle (C1-2 RRA) were measured, and lateral atlantoaxial joints osteoarthritis (LAJs-OA) was recorded. The stress distribution on the C2 facet surface under different torques of flexion-extension, lateral bending, and axial rotation was analyzed by FE models. A 2-Nm moment was applied to all models to determine the range of motion (ROM).

METHODS

A total of 132 consecutive cervical spondylosis patients with unilateral HRVA were enrolled in the HRVA group, and 264 patients without HRVA matched for age and sex were enrolled in the normal (NL) group. Atlantoaxial joint morphological parameters were compared between two sides of C2 lateral mass within HRVA or NL group, and between HRVA and NL groups. A 48-year-old woman with cervical spondylosis without HRVA was selected for cervical MSCT. A three-dimensional (3D) FE intact model of the normal upper cervical spine (C0-C2) was created. We established the HRVA model by simulating atlantoaxial morphological changes of unilateral HRVA with FE method.

RESULTS

The C2 LMS was significantly smaller on the HRVA side than that on the non-HRVA side in the HRVA group, but C1-2 SI, C1-2 CI, and LADI on HRVA side were significantly larger than those on non-HRVA side. There was no significant difference between left and right sides in the NL group. The difference in C2 LMS (d-C2 LMS) between HRVA side and non-HRVA side in the HRVA group was larger than that in the NL group (P < 0.05). Meanwhile, the differences in C1-2 SI (d-C1/2 SI), C1-2 CI (d-C1/2 CI), and LADI (d-LADI) in the HRVA group were significantly larger than those in the NL group. The C1-2 RRA in the HRVA group was significantly larger than that in the NL group. Pearson correlations showed that d-C1/2 SI, d-C1/2 CI, and d-LADI were positively associated with d-C2 LMS (r=0.428, 0.649, 0.498, respectively, p<.05 for all). The incidence of LAJs-OA in the HRVA group (27.3%) was significantly larger than that in the NL group (11.7%). Compared with the normal model, the ROM of C1-2 segment declined in all postures of the HRVA FE model. We found a larger distribution of stress on the C2 lateral mass surface of the HRVA side under different moment conditions.

CONCLUSIONS

We suggest that HRVA affects the integrity of the C2 lateral mass. This change in patients with unilateral HRVA is associated with the nonuniform settlement of the lateral mass and an increase in the lateral mass inclination, which may further affect the degeneration of the atlantoaxial joint because of the stress concentration on the C2 lateral mass surface.

[Clinical study of digital six-axis external fixation frame based on CT data for tibiofibular fractures]

Objective: To investigate the clinical effect of applying the digital six-axis external fixation frame based on CT data in the treatment of tibiofibular fractures. Methods: The clinical data of 43 patients with tibiofibular fractures treated by the self-developed digital six-axis external fixation frame based on CT data at Integrated Orthopedic Department of Traditional Chinese Medicine (TCM) and Western Medicine,HongHui Hospital from January 2018 to January 2021 were retrospective analysis.There were 27 males and 16 females,aged (36.0±9.4) years(range:25 to 50 years).AO classification:15 cases of 42A,11 cases of 42B, and 17 cases of 42C.There were 7 open fractures and Gustilo fracture classification:2 cases of type Ⅰ,4 cases of type Ⅱ,and 1 case of type Ⅲ.The two or three plane rings were connected with six connecting rods to form a complete six-axis external fixation frame,and the distal and proximal fracture blocks were connected to the distal and proximal rings by fixation pins,and the lengths of the six connecting rods needed to be adjusted were calculated by using the supporting software according to the CT data after surgery,and then the lengths of the connecting rods were adjusted one by one to complete the reduction of the fracture. The reduction accuracy of this six-axis external fixation brace was evaluated by measuring postoperative radiographs; postoperative recovery and complications were collected,the time of brace removal was recorded,and the function of the affected limb was evaluated according to the Johner-Wruhs score at the final follow-up. Results: Postoperative radiographs showed that all patients achieved satisfactory reduction with lateral displacement(M(IQR)) of 2.3(2.5) mm (range:0.3 to 7.3 mm),anteroposterior displacement of 2.1 (2.4) mm (range:0.3 to 5.7 mm),anteroposterior angulation of 2.5(2.4)°(range:0 to 5°),internal and external angulation of 2.1(1.5)°(range:0 to 4°), and no significant internal or external rotational deformity was detected on the exterior.On the second postoperative day,all patients were able to walk with partial weight-bearing on crutches. All 43 patients were followed up for more than 6 months,with a follow-up period of (33.3±7.3) weeks (range:24 to 42 weeks).The external fixation frame was removed after the fracture healed.The external frame was removed at 20(3)weeks (range:18 to 25 weeks) postoperatively. Up to the final follow up, no secondary fracture occurred in any of them.The Johner-Wruhs score of the affected limb at the last follow-up was excellent in 39 cases and good in 4 cases. Conclusion: The digital six-axis external fixator based on CT data for tibiofibular fractures has the advantages of precise reduction,firm fixation,simple operation,rapid fracture healing,and minimal trauma, which is a minimally invasive method for treating tibiofibular fractures,especially suitable for patients with poor skin and soft tissue conditions such as open injuries.

Classification of unilateral cervical locked facet with or without lateral mass-facet fractures and a retrospective observational study of 55 cases

This study describes a morphology-based unilateral cervical facet interlocking classification in an attempt to clarify the injury mechanism, instability, neurological deficits, radiological features, and determine optimum management strategies for these injuries. A total of 55 patients with unilateral cervical locked facet (UCLF) involving C3 to C7 were identified between January 1, 2012 and December 1, 2019. The injuries were classified into three types, and they were further divided into six subtypes using three-dimensional computed tomography. The injury mechanism, clinical features, neurological deficits, and imaging characteristics were analyzed, and the appropriate treatment strategies for UCLF were discussed. UCLFs were divided into the following six subtypes: UCLF without lateral mass-facet fracture (type I) in nine cases, with superior articular process fracture (type II A) in 22, with inferior articular process fracture (type II B) in seven, both superior and inferior articular process fractures (type II C) in four, with lateral mass splitting fracture (type III A) in three, and with lateral mass comminution fractures (type III B) in ten. A total of 22 (40.0%) of the 55 patients presented with radiculopathy, and 23 patients (41.8%) had spinal cord injuries. The subtype analyses showed high rates of radiculopathy in types II A (68.2%) and II C (75.0%), as well as significant spinal cord injury in types I (77.8%) and III (61.5%). Destruction of the facet capsule was observed in all patients, but the injury of disc, ligamentous complex, and vertebra had a significant difference among the types or subtypes. The instability parameters of the axial rotation angle, segmental kyphosis, and sagittal displacement showed significant differences in various types of UCLF. Closed reduction by preoperative and intraoperative general anesthesia traction was achieved in 27 patients (49.1%), and successful rate of closed reduction in type I (22.2%) was significantly lower than that in type II (51.5%) and type III (61.5%). A total of 35 of 55 patients underwent a single anterior fixation and fusion, 10 patients were treated with posterior pedicle and (or) lateral mass fixation, and combined surgery was performed in ten patients. Ten patients (18.2%) with a poor outcome were observed after first surgery. Among them, 3 patients treated with a single anterior surgery had persistent or aggravated radiculopathy and posterior approach surgery with ipsilateral facet resection, foramen enlargement, and pedicle and (or) lateral mass screw fixation was performed immediately, 5 patients treated with a short-segment posterior surgery showed mild late kyphosis deformity, and 2 patients with vertebral malalignment were encountered after anterior single-level fusion during the follow-up. This retrospective study indicated that UCLF is a rotationally unstable cervical spine injury. The classification proposed in this study will contribute to understanding the injury mechanism, radiological characteristics, and neurological deficits in various types of UCLF, which will help the surgeons to evaluate the preoperative closed reduction and guide the selection of surgical approach and fusion segment.

What is the difference in pedicle morphology of the fifth lumbar vertebra between isthmic and degenerative L5-S1 spondylolisthesis? An anatomic study of 328 patients via multi-slice spiral computed tomography

PURPOSE

The purpose of this study was to investigate and determine whether there are differences in L5 pedicles morphology between isthmic and degenerative L5-S1 spondylolisthesis.

METHODS

One hundred and nineteen patients with isthmic spondylolisthesis and 45 patients with degenerative spondylolisthesis at L5-S1 were enrolled in the IS group and DS group, respectively, and 164 lumbar disc herniation patients without spondylolysis or spondylolisthesis were classified into the normal (NL) group. A series of pedicle parameters of the fifth lumbar vertebra, including pedicle length (PL), pedicle width (PW), pedicle screw trajectory length (PSTL), pedicle height (PH), and the pedicle camber angle (PCA), were measured using multi-slice spiral computed tomography (MSCT). The slip distance of the L5 vertebra was measured on radiography, and the percentage of slip was also recorded.

RESULTS

The pedicles of the fifth lumbar vertebra were shorter and wider, and the PCA was larger in the IS group compared to the DS group and NL group. On the contrary, the pedicles in the DS group were elongated and thinner, and the PCA was smaller. The pedicle parameters of PL were significantly positively correlated with the percentage of slip in the DS group, but PW and PCA were negatively correlated with the percentage of slip. There was no correlation between the percentage of slip and L5 pedicle parameters in the IS group.

CONCLUSIONS

The L5 pedicles morphology in L5-S1 isthmic spondylolisthesis shows abduction, shortness, and width, while that in the degenerative spondylolisthesis shows adduction, lengthening, and thinning compared with the normal populations. The morphology changes may be the result of pedicle stress remodelling in the development of spondylolisthesis, which should be taken into consideration when placing at the insertion of pedicle screws.

A novel method for measurement of the occipital-cervical distance via the occiput-C4 distance

Background

The aim of the present study was to describe and measure the occipital-cervical distance by a novel method utilizing the occiput-C4 distance (OC4D) in normal subjects, as a proposed tool to guide restoration of vertical dislocations of the occipitocervical region in patients with basilar invaginations and for performing standardized testing of occipitocervical constructs.

Methods

We analyzed neutral, flexion, and extension lateral cervical spine radiographs of 150 asymptomatic subjects (73 males and 77 females) that were judged to be normal. The mean age of the included asymptomatic subjects was 48.0 ± 8.4 years old (range 20–69 years old; 48.4 ± 10.2 years old for males and 47.6 ± 6.4 years old for females). The OC4D was defined as the shortest distance from the center of the C4 vertebral body to the McGregor’s line. Occipitocervical distances (OCDs) were measured and analyzed its correlation with OC4Ds. Two spine surgeons each performed three measurements of the OC4D and OCD from each asymptomatic subject, from which our reported average values were derived. The height, weight, and body mass index (BMI) of each subject were recorded and analyzed for their correlations with the OC4D and OCD.

Results

The OC4Ds from neutral, flexion, and extension lateral cervical spine radiographs were 69.0 ± 6.9, 68.9 ± 6.8, and 68.1 ± 6.9 mm, respectively. There was no significant difference in the OC4D values among neutral, flexion, and extension lateral cervical spine radiographs (P >  0.05). The neutral, flexion, and extension OCDs were 23.0 ± 4.8, 27.6 ± 6.0, and 13.8 ± 4.7 mm, respectively. In particular, the neutral OCD was significantly different from those in flexion and extension lateral cervical spine radiographs (P <  0.001). There was no significant correlation between OC4D and OCD in neutral, flexion, and extension (P >  0.05 for all). There were positive correlations between OC4D and height, as well as OC4D and weight, in neutral, flexion, and extension lateral cervical spine radiographs (P <  0.001 for all). Furthermore, the intra-class correlation coefficients for inter- and intra-observer reliabilities of OC4Ds in neutral, flexion, and extension lateral cervical spine radiographs were significantly higher than those for OCDs (P <  0.001).

Conclusions

The OC4D represents a novel measurement for estimating the occipital-cervical distance that is not affected by changes in neutral, flexion, and extension positions. Hence, the OC4D may serve as a valuable parameter and intra-operative tool to guide vertical restoration during occipitocervical fusion (OCF) for patients with altered occiput-cervical anatomy.

The efficacy and safety of topical rapamycin-calcitriol for facial angiofibromas in patients with tuberous sclerosis complex: a prospective, double-blind, randomized clinical trial

BACKGROUND

The efficacy of topical rapamycin is well documented for tuberous sclerosis complex (TSC)-related facial angiofibromas (FAs). Calcitriol has been shown to lessen skin fibrosis and may be therapeutically beneficial to FAs.

OBJECTIVES

To evaluate whether topical rapamycin-calcitriol combination is an effective and safe treatment for TSC-related FAs.

METHODS

Fifty-two patients with TSC with FAs were enrolled in this prospective study including three 12-week periods. In period 1, either topical rapamycin 0·1% or calcitriol 0·0003% single-agent therapy vs. their combination was applied in a double-blind, left-right-randomized, split-face comparison. The primary outcome was the reduction of modified Facial Angiofibroma Severity Index (mFASI) at week 12. In period 2, the patients were reassigned to use on both cheeks the ointment that resulted in the better primary outcome in period 1. The treatment was discontinued in period 3 (week 25-36) and a follow-up mFASI was scored to evaluate the degree of recurrence.

RESULTS

The mean changes in mFASI at week 12 compared with baseline were -0·92, -0·44 and -1·09 for rapamycin (P ≤ 0·001), calcitriol (P = 0·039) and rapamycin-calcitriol combination (P ≤ 0·001), respectively. Although rapamycin-calcitriol combination and rapamycin had similar statistically significant decreases of mFASI at week 12, rapamycin-calcitriol combination resulted in faster improvement in erythema, greater reduction of papule elevation and longer durability after discontinuing treatment than rapamycin alone. The treatments were well tolerated.

CONCLUSIONS

This randomized clinical trial demonstrates that topical rapamycin-calcitriol combination therapy is an effective and safe regimen for TSC-related FAs. What is already known about this topic? Facial angiofibromas (FAs) cause substantial psychological distress in individuals with tuberous sclerosis complex (TSC), but invasive procedural treatments are not applicable to all patients. Topical rapamycin has been demonstrated as an effective and safe treatment regimen for TSC-related FAs. What does this study add? Compared with baseline (day 0), both topical rapamycin 0·1% and rapamycin 0·1%-calcitriol 0·0003% combination ointment achieved statistically significant reductions in modified Facial Angiofibroma Severity Index at week 12. Compared with rapamycin alone, extended use of the rapamycin-calcitriol combination regimen until week 24 showed more effectiveness in decreasing papule elevation and could maintain a longer therapeutic effect after treatment discontinuation. Linked Comment: Lee. Br J Dermatol 2020; 183:604-606.

Importance of the Occipitoaxial Angle and Posterior Occipitocervical Angle in Occipitocervical Fusion

OBJECTIVE

To observe the effects of occipitoaxial angle (O-C2 angle, OC2A) and posterior occipitocervical angle (POCA) selection on postoperative clinical efficacy and lower cervical curvature in patients with acute acquired atlantoaxial dislocation after occipitocervical fusion (OCF).

METHODS

A total of 150 healthy subjects without cervical disease (healthy group) were randomly selected based on gender and age. Three spine surgeons measured the OC2A and POCA of the healthy group and averaged the values. A total of 30 patients with an average age of 51.0 years (range, 18-70 years; 16 male and 14 female) with trauma or rheumatoid arthritis (disease group) who underwent occipitocervical fusion (OCF) for atlantoaxial dislocation between January 2012 and June 2016 were reviewed. OC2A, POCA, and cervical spinal angle (CSA) were measured postoperative/soon after surgery and ambulation, and at the final follow-up visit. The preoperative and final follow-up visual analog scale (VAS), Japanese orthopedics association score (JOA), neck disability index (NDI), and dCSA (change of CSA from postoperative/soon after surgery and ambulation to final follow-up) were recorded.

RESULTS

The values of OC2A and POCA in 150 healthy subjects were 14.5° ± 3.7° and 108.2° ± 8.1°, respectively, and the 95% confidence interval (CI) were 7.2°-21.8° and 92.3°-124.0°, respectively. There was a negative correlation between OC2A and POCA (r = -0.386, P < 0.001). There were 18 patients (group one) of ideal OC2A and POCA (both within 95% CI of the healthy group) postoperative/soon after surgery and ambulation with a mean follow-up time of 26.3 ± 20.9 months in disease group. The remaining patients (group two) with a mean follow-up time of 31.3 ± 21.3 months. There was no statistically significant difference in the baseline data as well as pre-operative outcomes, including VAS score, JOA score, and NDI between the two groups. Likewise, the post-operative outcomes in final follow-up, including VAS and JOA score, had no distinct difference in the two groups. However, NDI (11.0 ± 2.9) in group two at the final follow-up was significantly higher than that in group one (7.0 ± 2.3) (P < 0.001). And group two showed statistically greater dCSA (5.9 ± 7.5°) than group one (-2.3° ± 6.2°) (P = 0.003).

CONCLUSIONS

The negative correlation between OC2A and POCA plays an important role in maintaining the biodynamic balance of the occipital-cervical region. OC2A and POCA should be controlled of a normal population in patients with acute acquired atlantoaxial dislocation during OCF, which can further improve the clinical efficacy and prevent loss of lower cervical curvature after surgery.

Nocardial spinal epidural abscess with lumbar disc herniation: A case report and review of literature

RATIONALE

Nocardial spinal epidural abscess is rare. The diagnosis is often difficult to make and, if delayed, poses a high risk of long-term disability. Nocardial spinal epidural abscess with severe lumbar disc herniation has not previously been reported.

PATIENT CONCERNS

A 50-year-old man presented with progressive lumbago and leg pain for 6 weeks after receiving acupuncture therapy, and then the patient suddenly occurred urine retention after walking.

DIAGNOSES

Clinical examination revealed sign of cauda equina syndrome. Magnetic resonance imaging (MRI) revealed a Lumbar(L)4 to L5 disc herniation, L3 to Sacrum(S)1 epidural abscess, and L2 to S1 paravertebral abscess. The causative organism was Nocardia farcinica.

INTERVENTIONS

An urgent paravertebral abscess debridement and right L4 to L5 laminectomy were performed. Simultaneously, the disc tissue protruding into the spinal canal was removed, as well as irrigation and drainage. And antimicrobial treatment was continued for 12 months.

OUTCOMES

Fortunately, the patient was able to walk with a cane and urinate autonomously without a catheter, although this remained difficult 7 days after surgery. After 1 year of treatment, the patient has recovered completely and returned to work.

LESSONS

Nocardial spinal epidural abscess with severe lumbar disc herniation is extremely rare. Pain from spinal degenerative diseases often masks the early symptoms of spinal infection. It's worth noting that invasive treatment of spine is a way of causing spinal nocardial infection.

The use of intraoperative traction for achieving reduction of irreducible atlantoaxial dislocation caused by different craniovertebral junction pathologies

OBJECTIVE

To investigate the usefulness of intraoperative traction in the selection of the surgical procedure for irreducible atlantoaxial dislocation (IAAD) caused by different craniovertebral junction (CVJ) pathologies.

PATIENTS AND METHODS

Forty-three patients who were diagnosed with IAAD and who underwent surgery between January 2008 and May 2017 in our hospital were included in the study. All of the patients received skull traction under general anesthesia. Based on the traction results, the patients underwent one of the following surgeries: posterior fixation and fusion only, posterior atlantoaxial lateral mass joint release followed by fixation and fusion, or anterior release followed by posterior fixation and fusion. The classification system was defined accordingly. The treatment efficacy was evaluated based on the improvement of clinical symptoms and radiological findings.

RESULTS

Four patients were categorized as Type A, twenty patients as Type B1, twelve patients as Type B2, and seven patients as Type C. Thirty-seven patients (86.0%) achieved complete reduction and six patients (14.0%) achieved greater than 50% reduction. Bony fusion was achieved in all patients at 6 months after the operation. The average Japanese Orthopaedic Association (JOA) score improved from 10.2 ± 2.1 before surgery to 15.0 ± 1.2 at the final follow-up. According to the Symon clinical standard, the total effectiveness rate was 97.7%, and 72.1% of the patients showed excellent clinical outcomes.

CONCLUSION

Intraoperative traction is an effective and safe method to assist the selection of surgical methods for patients with IAAD caused by different CVJ etiologies.

Revision surgery after rod breakage in a patient with occipitocervical fusion: A case report

RATIONALE

Rod breakage after occipitocervical fusion (OCF) has never been described in a patient who has undergone surgery for basilar invagination (BI) and atlantoaxial dislocation (AAD). Here, we present an unusual but significant case of revision surgery to correct this complication.

PATIENT CONCERNS

A 32-year-old female presented with neck pain, unstable leg motion in walking, and also BI with AAD. Her first surgery was planned to correct these conditions and for fusion at the occipital junction (C3-4) using a screw-rod system. At the 31-month follow-up after her first operation, the patient complained of severe neck pain and limitation of motion, suggesting rod breakage.

DIAGNOSES

Rod breakage after occipitocervical fusion for BI and AAD.

INTERVENTIONS

The patient underwent reoperation for replacement of the broken rods, adjustment of the occipitocervical angle, maintenance of the bone graft bed, and fusion.

OUTCOMES

At follow-up, the hardware was found to be in good condition, with no significant loss of cervical lordosis. At the 37-month follow-up after her second operation, the patient was doing better and continuing to recover.

LESSONS

We concluded that nonideal choice of occipitocervical angle may play an important role in rod breakage; however, an inadequate bone graft and poor postoperative fusion may also contribute to implant failure.

[Pre- and post-orthotopic heart transplantation electrocardiogram characteristics of 998 patients]

Objective: To analyze pre- and post-operation electrocardiograms (ECGs) features of patients underwent orthotopic heart transplantation (OHT), and provide evidences for identifying and analyzing post OHT ECGs. Methods: Nine hundreds and ninty-eight pre- and post- OHT standard 12-leads ECGs from 110 consecutive patients, who underwent OHT in our hospital from May 2008 to May 2014, were analyzed. Results: The mean heart rate(HR)was (86.9±16.4) beats per minute before OHT, and (100.0±0.4) beats per minute after OHT. P wave's amplitude, duration, amplitude multiplied by duration of donor heart in lead Ⅱ were (0.124±0.069)mV, (111.1±17.2)ms, (14.34±9.51)mV·ms before OHT; (0.054±0.037)mV, (86.9±27.0)ms, (5.02±4.03)mV·ms at 1 month after OHT; (0.073±0.049)mV, (93.9±17.5) ms, (7.00±4.81)mV·ms at 6 years after OHT. ECGs rotation occurred in 83.64%(92/110) patients after OHT, and prevalence of clockwise rotation was 76.36%(84/110). Sinus tachycardia was evidenced in 99.09%(109/110) patients after OHT, and incomplete right bundle branch block was present in 60.91%(67/110) patients after OHT. Pseudo complete atrioventricular block mostly occurred at 2 days after OHT. Prevalence of double sinus rhythm was 27.95%(263/941) post OHT, 40% of them occurred between the 1st and the 2nd month post OHT; the atrial rate of recipient hearts was (104.0±10.2) beats per minucte between the 3rd and the 6th month post OHT, and was (95.3±4.2) beats per minucte between the 4th year and the 5th year. P wave's amplitude, duration, amplitude multiplied by duration of recipient heart in lead Ⅱ were (0.066±0.055) mV, (52.8±34.7) ms, (4.67±4.95) mV·ms at 1 month after OHT, (0.043±0.040)mV, (44.4±40.5) ms , (3.11±3.61) mV·ms between the 1st year and 2nd year after OHT. The absolute value of P-wave(originating from the donor heart) terminal force in chest leads increased in 48.99%(461/941) patients post OHT, the P-wave terminal force of V(1) , V(2) and V(3) were -0.044(-0.066, -0.028), -0.060(-0.087, -0.038), -0.035(-0.056, 0) mm·s. Notched P wave in chest leads was presented in 10.31%(97/941) patients post OHT. PR segment depression in chest leads occurred in 60.24%(100/166) patients between the 3rd month and the 6th month, the incidence of PR segment depression in V(1) , V(2) and V(3) was 21.04%(198/941), 37.41%(352/941) and 28.69%(270/941), respectively. Conclusions: OHT is related to significantly changed ECGs. The mean HR increased significantly after OHT, then decreased gradually after half a year to one year, but it was still higher than preoperative mean HR after five or six years; the P waves of donor heart were usually inconspicuous or small in first month after OHT, and they became bigger after 2 months, and their duration and amplitude then became relatively steady afterwards. ECGs rotation, especially the clockwise rotation, was common post OHT. A variety of arrhythmias originating from the donor heart including sinus tachycardia and incomplete right bundle branch block could be found. Pseudo complete atrioventricular block could also be found in the early phase after OHT. With the extension of time, the incidence of double sinus rhythm reduced gradually. The atrial rate and P wave of recipient heart presented with a tendency to become lower. The absolute value of P-waves(originating from the donor heart) terminal force in chest leads (mainly V(1), V(2) and V(3)) increased, notched P waves in chest leads (mainly V(1), V(2)) and PR segments depression in chest leads (mainly V(2), V(3) and V(4)) also belong to typical post OHT ECGs features.

Particle size effect of curcumin nanosuspensions on cytotoxicity, cellular internalization, in vivo pharmacokinetics and biodistribution

This study aimed to investigate the particle size effect on bioactivity, cellular internalization and bioavailability of curcumin (CUR) nanosuspension (CUR-NS). CUR-NSs of different particle sizes were prepared by two different anti-solvent precipitation methods. CUR-NS with the smallest size showed similar in vitro anticancer activity and bioavailability to the CUR solution, whereas nanosuspensions of larger particle sizes displayed higher in vitro cellular internalization and cytotoxicity, as well as higher in vivo AUC and slower clearance rate after i.v. administration in rats. CUR solution and different sized CUR-NSs reached the highest concentrations in the lung, followed by liver and spleen while the lowest concentration was observed in the brain after i.v. administration in mice. Specifically, CUR-NS of 70nm accumulated more in the brain, whereas CUR-NS of 200nm accrued more in liver and spleen. CUR-NS of 20nm displayed no significant biodistribution difference compared with CUR solution in all tissues.

Increased expression of the natural killer cell inhibitory receptor CD94/NKG2A and CD158b on circulating and lesional T cells in patients with chronic plaque psoriasis

BACKGROUND

Psoriasis is a common inflammatory cutaneous disorder characterized by activated T-cell infiltration. T lymphocytes bearing natural killer cell receptors (NKRs) have been suggested to play an important role in the pathogenesis of psoriasis. However, the expression pattern of activating and inhibitory NKRs on T lymphocytes from psoriatic patients and its significance in psoriasis needs further study.

OBJECTIVES

To investigate the pathogenesis of NKR-expressing T cells in psoriasis.

MATERIALS AND METHODS

Thirty patients with chronic plaque psoriasis and 20 healthy controls were enrolled in this study. The immunophenotypic profiles of NKRs, including CD56, CD16 (activating NKRs), CD158a, CD158b, CD94 and NKG2A (inhibitory NKRs), were analysed in peripheral blood T lymphocytes, as well as psoriatic lesional infiltrating T cells, by triple-fluorescence flow cytometry.

RESULTS

A significant increase of inhibitory CD8+ CD158b+, CD4 CD8 CD158b+ and CD8+ CD94/NKG2A+ T cells was found in the peripheral blood of patients with psoriasis when compared with controls. Tissue-infiltrating T lymphocytes expressing inhibitory receptors CD158b, CD94 and NKG2A were found in psoriatic lesions. There was a significant positive correlation between the increased percentage of circulating CD8+ CD94/NKG2A+ T cells and the Psoriasis Area and Severity Index.

CONCLUSIONS

In the present study, we demonstrated increased proportions of particular subsets of inhibitory CD158b+ and/or CD94/NKG2A+ T cells in patients with psoriasis. The elevation of these inhibitory NKR-expressing T cells was correlated with disease severity, which may signify the possibility of chronic antigen-driven stimulation and dysregulated cytokine production in the pathogenesis of psoriasis.

Development of interesting step-climbing styles

OBJECTIVES

This study was to investigate the influence of stepping styles (forward, side, and cross steppings) and inclinations (25 and 45 degrees) on cardiorespiratory responses (C-R responses).

METHODS

Twenty volunteers were recruited and randomly arranged into two ten-people groups, exercising on step-climbing machines respectively of 25 and 45 degrees of inclination. C-R responses were recorded during each test which lasted for six minutes at 50 steps per minute on a step-climbing machine.

RESULTS

The group on 25-degree inclination had significantly lower C-R responses than the group on 45-degree inclination. Although only small differences, probably statistically insignificant, were found among the three step-climbing styles, these differences showed interesting trends independent of inclination.

CONCLUSIONS

Climbing stairs with the three interesting step-climbing styles in this study could be considered as an exercise of moderate intensity (60-80% HRmax ). Climbing on 25-degree inclination at 50 steps per minute is recommended for less fit individuals because of lower cardiovascular stress as compared with on 45-degree inclination.

The phosphotidyl inositol 3-kinase/Akt signal pathway is involved in interleukin-6-mediated Mcl-1 upregulation and anti-apoptosis activity in basal cell carcinoma cells

Dysregulation of interleukin-6 has been reported to be associated with various types of tumors, and interleukin-6 plays an important part in regulating apoptosis in many types of cells. Previously, Mcl-1 was shown to be significantly increased in interleukin-6-overexpressed basal cell carcinoma cells and conferred on them anti-apoptotic activity. The aim of this study was to investigate which signaling pathway is involved in the anti-apoptotic effect of interleukin-6 on basal cell carcinoma cells. Here we show that the addition of recombinant 100 ng per ml interleukin-6 to basal cell carcinoma cells induced a 2.3-fold increase in the level of Mcl-1 protein in basal cell carcinoma cells. Transfection with dominant-negative STAT3 (STAT3F) into inter-leukin-6-treated basal cell carcinoma cells caused a decrease of phosphotyrosyl STAT3 but did not alter Mcl-1 protein levels; however, AG490, a Janus tyrosine kinase inhibitor, was capable of inhibiting the interleukin-6-induced elevation of Mcl-1 protein. Next, interleukin-6 stimulation elicited extracellular signal-regulated kinase activation in basal cell carcinoma cells, and the mitogen-activated protein kinase inhibitor, PD98059, could affect this response without affecting the interleukin-6-medi-ated Mcl-1 upregulation. Use of the two phosphotidyl inositol 3-kinase inhibitors, LY294002 and wortmannin, to check whether this pathway is involved in Mcl-1 upregulation by interleukin-6, we found that the phosphotidyl inositol 3-kinase inhibitors completely attenuated the interleukin-6-induced Mcl-1 upregulation. Furthermore, in the interleukin-6-overexpressing basal cell carcinoma cell clone, dominant-negative Akt also significantly reduced the increased level of Mcl-1. Interestingly, Janus tyrosine kinase inhibitor, AG490, treatment strongly blocked the phosphotidyl inositol 3-kinase pathway activation, as evidenced by the decrease in phospho-Akt level. Blockage of phosphotidyl inositol 3-kinase/Akt pathway abolished the interleukin-6-mediated anti-apoptotic activity in ultraviolet B treated cells. Unexpectedly, without ultraviolet B irradiation, STAT3F transfection also induced a significant apoptosis in basal cell carcinoma/interleukin-6 cells. Taken together, our data suggest that both the phosphotidyl inositol 3-kinase/Akt and STAT3 pathways are potentially involved in interleukin-6-mediated cell survival activity in basal cell carcinoma cells; however, the upregulation of the anti-apoptotic Mcl-1 protein by interleukin-6 is mainly through the Janus tyrosine kinase/phosphotidyl inositol 3-kinase/Akt, but not the STAT3 pathway.

The frequency of occurrence of autoantibodies against beta1-adrenoceptors and its clinical relevance in patients with hepatitis virus myocarditis

The aim of this study was to examine the frequency of occurrence of autoantibodies against beta1-adrenoceptors in patients with hepatitis virus myocarditis (HVM) and its possible correlation with clinical characteristics. A total of 103 patients with viral myocarditis were divided into a positive group (HVM group, n=29) and a negative group (Non-HVM group, n=74) according to the laboratory findings regarding their type of hepatitis virus. The study parameters included UCG, ECG, biochemical findings and screening of autoantibodies against beta1-adrenoceptor. It was shown that the positive rate of the hepatitis virus was 28.16% (29/103) in patients with viral myocarditis. The severity of myocardial or liver injuries and the frequency of occurrence of autoantibodies against beta1-adrenoceptors in patients with viral myocarditis were more pronounced, before treatment, in the HVM group than in the Non-HVM group. The positive rates of the antibodies against the hepatitis virus and the autoantibodies against beta1-adrenoceptors were highly consistent in patients with HVM (p<0.05). In conclusion, the frequency of occurrence of the autoantibodies against beta1-adrenoceptors may be one important marker of HVM and, thus, possibly involved in the pathogenesis of the HVM.

Pattern of skin diseases in a geriatric patient group in Taiwan: a 7-year survey from the outpatient clinic of a university medical center

BACKGROUND

Geriatric health care has become a worldwide concern, but relatively few statistical studies are available about geriatric skin diseases. Moreover, no information exists regarding skin disorders among the elderly population in Taiwan that has become a geriatric country.

OBJECTIVE

To determine the characteristic pattern and the prevalence of various skin disorders for the elderly who visited the National Taiwan University in the last 7 years.

METHODS

Using a database from the Dermatology Outpatient Clinic of the National Taiwan University Hospital, 1993-1999 file, we conducted a retrospective cross-sectional study by evaluating the age, proportion, and gender of each specific cutaneous disease category, chi(2) tests were used for analyzing statistical significance. The analysis supplied odds ratios and 95% confidence intervals.

RESULTS

A total of 16,924 patients aged 65 years and older, which constituted 11% of the total patients seen at the Clinic of Dermatology from 1993 through 1999, were studied. The male to female ratio was 1.3 to 1. The most common cutaneous disorder in the elderly was dermatitis (58.7%), followed by fungal infections (38.0%), pruritus (14.2%), benign tumors (12.8%), and viral infections (12.3%). Cutaneous malignant tumors were found in 2.1%. Basal cell carcinoma occurred in 29.8%, actinic keratosis in 22.4%, Bowen's disease in 13.3% and squamous cell carcinoma 13.3%. Interestingly, our cases of extramammary Paget's disease showed a male predominance. Most melanomas were acral lentiginous melanoma located on the soles. The prevalence of common diseases in elderly patients compared with those outpatients of less than 65 years showed a 3-fold increased risk for pruritus. Moreover, the pattern of geriatric skin diseases in Taiwan was significantly different from Western countries.

CONCLUSION

The prevalence of skin diseases in elderly patients emphasizes the importance of health education in geriatric people in Taiwan concerning appropriate use of emollients, proper foot care, sun protection and early detection of skin cancers.

Turbidimetric and HPLC assays for the determination of formulated lysozyme activity

In several studies lysozyme has been employed as a model protein to investigate the effects of formulation factors upon biological activity. The aim of this work was to develop and validate an HPLC technique to assay lysozyme and to compare the results with biological activity determined from a validated turbidimetric assay. The turbidimetric assay was based upon the lytic action of lysozyme on Micrococcus lysodeikticus cells, whilst the reverse-phase HPLC assay employed an acetonitrile gradient in 0.1% trifluoroacetic acid. The limits of detection and quantification were 3.84 and 6.24 microg mL(-1) for HPLC assay, whilst the corresponding values for turbidimetric assay were 1.94 and 3.86 microg mL(-1). The methods were used to monitor the loss of enzyme activity after heating. Lysozyme concentrations determined from HPLC peak height were found to correlate (r2 = 0.9963) with those obtained from turbidimetric assay.

Determination of alkylbenzyldimethylammonium chlorides in river water and sewage effluent by solid-phase extraction and gas chromatography/mass spectrometry

This study presents a modified method to analyze alkylbenzyldimethylammonium chlorides (ABDACs) in river water and sewage effluent. The method involves mixed samples with linear alkylbenzenesulfonates (LAS) as a counterion to enhance the extraction of ABDAC residues from an RP-18 solid-phase cartridge by formation of hydrophobic ion-pair complexes. The ABDACs were then eluted with methanol-ethyl acetate (1:1, v/v) and formed to their corresponding alkyldimethylamines by the Hofmann degradation with potassium tert-butoxide. The alkyldimethylamines were then identified and quantitated by gas chromatograph/mass spectrometry (GC/MS). The results indicate that, in the presence of LAS, debenzylation of ABDACs occurs selectively at a temperature higher than 90 degrees C to produce the corresponding nonionic alkyldimethylamines. The method proposed herein provides a high precision and sensitivity for ABDACs, to quantitation at < or =0.1 microg/L in 500 mL of the water samples. The average recovery of ABDAC spiked water samples was 95% with relative standard deviations (RSD, n = 7) of 9%. The RSDs of three replicate environmental sample analyses ranged from 5 to 11%. Direct HPLC method was applied to evaluate the GC/MS method, and compatible results were observed.

Novel and known constituents from Buddleja species and their activity against leukocyte eicosanoid generation

We have undertaken a systematic survey of the genus Buddleja used in traditional Chinese medicine for antiinflammatory and other indications by testing extracts and isolated natural products for their activity against the enzymes of the arachidonate cascade. This was done by using elicited rat peritoneal leukocytes, a physiologically relevant established whole cell system that expresses both cyclo-oxygenase (COX) and 5-lipoxygenase (5-LOX) activity. Lipophilic extracts of B. globosa roots and B. myriantha stem exhibited inhibitory activities in the 5-LOX and COX enzyme assays, whereas those of B. officinalis flowers, B. yunanesis stems, and B. asiatica stems showed inhibitory activities only against COX. The phytochemical investigation of these extracts, and consequent structure elucidation of isolated compounds using spectroscopic data, led to the isolation from B. globosa of three new terpenoid compounds named dihydrobuddledin A, buddledone A, and buddledone B and four known compounds-buddledins A, B, and C and zerumbone; 12 known compounds from B. officinalis-calceolarioside, campneoside, verbascoside, echinacoside, forsythoside B, angoroside A, crocetin monogentibiosyl ester, acacetin, acacetin-7-O-alpha-L-rhamnopyranosyl (1-6)-beta-D-glucopyranoside, acacetin-7-O-alpha-L-rhamnopyranosyl (1-6)[alpha-L-rhamnopyranosyl (1-2)]-beta-D-glucopyranoside, songarosaponin A, delta-amyrone; and eight known compounds fromB. yunanesis-11,14-dihydroxy-8,11, 13-abietatrien-7-one, beta-sitosterol, verbascoside, echinacoside, forsythoside B, angoroside A, methylcatapol, and sucrose. Tests on the isolated compounds for inhibition of eicosanoid synthesis showed that buddledin A, crocetin monogentibiosyl ester, and acacetin exhibited an inhibitory effect on COX with IC(50) values of 13.7 microM, 28.2 microM, and 77.5 microM, respectively, whereas buddledin A exhibited inhibitory effect on 5-LOX with an IC(50) value of 50.4 microM.

Interventional study of diltiazem in dilated cardiomyopathy: a report of multiple centre clinical trial in China. Chinese Cooperative Group of Diltiazem Intervention Trial in Dilated Cardiomyopathy

The aim of this study was to determine the interventional effects of diltiazem on autoantibody mediated myocardial damage in dilated cardiomyopathy (DCM). 221 patients with DCM in 16 hospitals were included in the multiple centre clinical trial from January 1995 to November 1996, using the diltiazem or placebo based on the background therapy for heart failure. Patients were randomly divided into groups for a single blind trial, followed by observation for an average of 7.4 months. After treatment, the heart function of 84% of patients in the diltiazem group recovered to grade I or II, but this occurred for 64% of patients in the placebo group. Heart-thorax ratio was decreased from 0.59+/-0.07 to 0.56+/-0.07 and the left ventricular end-diastolic dimension (LVEDd) from 65.40+/-8.60 mm to 61.12+/-9.86 mm, the left ventricular ejection fraction (EF) was increased from 35.75+/-10.78% to 42.52%+/-11.41% (P<0.01) in the diltiazem group (n=114). The above parameters were not significantly changed in the placebo group (n=107). Mortality was 3.5% in the diltiazem group and 11.2% in the placebo group (P<0.05). Further analysis also shows that LVEDd were reduced and EF were obviously elevated in patients with DCM of LVEDd <70 mm, but the above parameters weren't improved in patients of LVEDd >70 mm. The study suggests that diltiazem is safe and effective in the treatment of DCM, the action mechanism might be intervention in antibody-mediated myocardial damage and protection of myocardium. Diltiazem is suitable for the treatment of the early stage in DCM.

Functional analysis of autoantibodies against ADP/ATP carrier from dilated cardiomyopathy

The aim of this article is to briefly review the immunological features of the autoantibodies against ADP/ATP carrier from dilated cardiomyopathy and the potential role of the autoantibodies in cardiac tissue injury. The autoantibodies against ADP/ATP carrier were found with very high frequency in patients with dilated cardiomyopathy, and had disease- and organ-specificity. The autoantibodies cross-reacted with subunits of the calcium channel on the cardiac cell membrane. There is a close correlation between the autoantibody-titer and the hemodynamic function in patients with dilated cardiomyopathy. It can be postulated that after an autoimmune response is initiated, the circulating autoantibodies against ADP/ATP carrier disturb myocardial energy metabolism, and enhance calcium influx and calcium overload in cardiac myocytes, resulting in progressive myocyte damage. These findings indicate a new immunopathological mechanism in dilated cardiomyopathy.

Dynamics of distributed-feedback fiber lasers: effect of nonlinear refraction

We present a model for the dynamics of distributed-feedback fiber lasers that includes the effect of nonlinear refraction. The model predicts antiphase and in-phase self-pulsations, asymmetric output, and deterministic chaos if the nonlinear refractive index of the fiber material is sufficiently large. Self-pulsations with frequencies of tens to hundreds of megahertz and pulse widths of several nanoseconds are observed in computer simulations.

Clinical observations of virologically confirmed dengue fever in the 1987 outbreak in southern Taiwan

Fifty-nine virologically confirmed cases of dengue fever were clinically studied during the 1987 outbreak in southern Taiwan. Viral isolation and serologic studies indicated that type 1 dengue was the cause. Dengue fever has not been on the island of Taiwan for 42 years and nearly all the population under 42 years of age is susceptible. Most patients under age 42 experience primary infection while those over 42 years old experience secondary infection. The majority of 59 cases studied were females in the 21-30-year age group. Classic signs and symptoms ere fever, headache, muscle pain, joint pain, nausea and vomiting, and skin rash. Approximately 80% of the patients had leukopenia (less than 5,000/mm3) and thrombocytopenia (less than 50,000/mm3) and 90% experienced mild to moderate elevation of serum glutamic oxaloacetic transaminase. Hemorrhagic manifestations occurred in 25.4% of patients. No patients under observation in this study developed hypotension or died.

Ventilatory responses to carbon dioxide and hypoxia during acupuncture anesthesia in rabbits

Ventilatory responses to CO2 or hypoxia were examined in rabbits during acupuncture anesthesia and compared with responses during pentobarbital anesthesia. The responses during pentobarbital anesthesia were significantly less than those during acupuncture anesthesia. The results showed that acupuncture analgesia was effective during performance of these experiments.