Does the angle between dynamic hip screw and anti-rotation screw affect the outcome of vertically oriented femoral neck fractures? A biomechanical analysis and clinical results

OBJECTIVE

To analyze the effects of the angle between dynamic hip screw (DHS) and anti-rotation screw (AS) on vertically oriented femoral neck fractures (VOFNFs) and investigate the clinical results of them.

METHODS

Eighteen synthetic femurs were simulated and divided into 3 groups. The angle between DHS and AS in anteroposterior-view was marked as α, and in lateral-view was marked as β, thus the total angle (TA) was defined as the summation of α and β. The groups were categorized as group A (TA ≤ 5°), B (5° < TA ≤ 10°), and C (TA > 10°), respectively. All samples were tested under incremental, cyclical loading, and loading to failure. In clinic, 80 consecutive VOFNFs in 78 patients were treated with DHS plus AS. The patients were divided into 2 groups, including 48 fractures in parallel group (TA ≤10°) and 32 in angular group (TA >10°).

RESULTS

Group A and B survived during incremental and cyclical loading and endured longer than group C. Axial stiffness and failure loads were not different between group A and B, and greater than group C. Fracture gaps compressive stress was highest in group A, followed by group B and C. Forty-one fractures in parallel group and 23 in angular group healed at final follow-up. Nonunion and osteonecrosis occurred in 3 and 4 of parallel group, and 4 and 5 of angular group.

CONCLUSION

The construction with TA ≤10° between DHS and AS showed superior biomechanical performance and clinical results than those with TA >10°.

CCL2 Potentiates Inflammation Pain and Related Anxiety-Like Behavior Through NMDA Signaling in Anterior Cingulate Cortex

Previous studies have shown that the C-C motif chemokine ligand 2 (CCL2) is widely expressed in the nervous system and involved in regulating the development of chronic pain and related anxiety-like behaviors, but its precise mechanism is still unclear. This paper provides an in-depth examination of the involvement of CCL2-CCR2 signaling in the anterior cingulate cortex (ACC) in intraplantar injection of complete Freund's adjuvant (CFA) leading to inflammatory pain and its concomitant anxiety-like behaviors by modulation of glutamatergic N-methyl-D-aspartate receptor (NMDAR). Our findings suggest that local bilateral injection of CCR2 antagonist in the ACC inhibits CFA-induced inflammatory pain and anxiety-like behavior. Meanwhile, the expression of CCR2 and CCL2 was significantly increased in ACC after 14 days of intraplantar injection of CFA, and CCR2 was mainly expressed in excitatory neurons. Whole-cell patch-clamp recordings showed that the CCR2 inhibitor RS504393 reduced the frequency of miniature excitatory postsynaptic currents (mEPSC) in ACC, and CCL2 was involved in the regulation of NMDAR-induced current in ACC neurons in the pathological state. In addition, local injection of the NR2B inhibitor of NMDAR subunits, Ro 25-6981, attenuated the effects of CCL2-induced hyperalgesia and anxiety-like behavior in the ACC. In summary, CCL2 acts on CCR2 in ACC excitatory neurons and participates in the regulation of CFA-induced pain and related anxiety-like behaviors through upregulation of NR2B. CCR2 in the ACC neuron may be a potential target for the treatment of chronic inflammatory pain and pain-related anxiety.

Peripheral BDNF Regulates Somatosensory-Sympathetic Coupling in Brachial Plexus Avulsion-Induced Neuropathic Pain

Brachial plexus avulsion (BPA) is a combined injury involving the central and peripheral nervous systems. Patients with BPA often experience severe neuropathic pain (NP) in the affected limb. NP is insensitive to the existing treatments, which makes it a challenge to researchers and clinicians. Accumulated evidence shows that a BPA-induced pain state is often accompanied by sympathetic nervous dysfunction, which suggests that the excitation state of the sympathetic nervous system is correlated with the existence of NP. However, the mechanism of how somatosensory neural crosstalk with the sympathetic nerve at the peripheral level remains unclear. In this study, through using a novel BPA C7 root avulsion mouse model, we found that the expression of BDNF and its receptor TrκB in the DRGs of the BPA mice increased, and the markers of sympathetic nervous system activity including α1 and α2 adrenergic receptors (α1-AR and α2-AR) also increased after BPA. The phenomenon of superexcitation of the sympathetic nervous system, including hypothermia and edema of the affected extremity, was also observed in BPA mice by using CatWalk gait analysis, an infrared thermometer, and an edema evaluation. Genetic knockdown of BDNF in DRGs not only reversed the mechanical allodynia but also alleviated the hypothermia and edema of the affected extremity in BPA mice. Further, intraperitoneal injection of adrenergic receptor inhibitors decreased neuronal excitability in patch clamp recording and reversed the mechanical allodynia of BPA mice. In another branch experiment, we also found the elevated expression of BDNF, TrκB, TH, α1-AR, and α2-AR in DRG tissues from BPA patients compared with normal human DRGs through western blot and immunohistochemistry. Our results revealed that peripheral BDNF is a key molecule in the regulation of somatosensory-sympathetic coupling in BPA-induced NP. This study also opens a novel analgesic target (BDNF) in the treatment of this pain with fewer complications, which has great potential for clinical transformation.

Brachial plexus avulsion induced changes in gut microbiota promotes pain related anxiety-like behavior in mice

Introduction

Brachial plexus avulsion (BPA) injury develops frequent and intense neuropathic pain, involving in both peripheral and central nervous systems. The incidence of anxiety or depression caused by BPA-induced neuropathic pain is high, but the underlying mechanism remains unclear.

Methods

We established a BPA mice model and assessed its negative emotions through behavioral tests. To further explore the role of the microbiota-gut-brain axis in the unique emotional behavior after BPA, we performed intestinal fecal 16s and metabolomics assays. Psychobiotics (PB) supplementation was administered to BPA mice to check the probiotics effects on BPA-induced anxiety behaviors.

Results

Pain related anxiety-like behavior was observed at the early stage after BPA (7 days), while no depression-like behavior was detected. Intriguingly, gut microbiota diversity was increased in BPA mice, and the most abundant probiotics, Lactobacillus, showed obvious changes. Lactobacillus_reuteri was significantly decreased in BPA mice. Metabolomics analysis showed that Lactobacillus_reuteri-related bile acid pathway and some neurotransmitter amino acids were significantly altered. Further PB (dominated by Lactobacillus_reuteri) supplementation could significantly relieve BPA-induced anxiety-like behaviors in mice.

Conclusion

Our study suggests that pathological neuralgia after BPA could alter intestinal microbiota diversity, especially Lactobacillus, and the changes in neurotransmitter amino acid metabolites may be the key reason for the onset of anxiety-like behaviors in BPA mice.

Case report: A rare case of massive peripheral nerve melanotic schwannoma and review of the literature

Melanotic schwannoma is a rare tumor with indeterminate biologic behavior and varying treatment recommendations. Just about 200 cases have been reported worldwide, in which occurred in peripheral nerves has even less reported. Due to the lack of cognition of melanotic schwannoma, it is easy to be misdiagnosed and mistreatment in primary hospitals. Herein, we presented a case of massive melanotic schwannoma growing in the brachial plexus of an elderly male patient. First, the patient underwent a left forearm tumor resection in the local primary hospital because a painless lump was found there in 2017, of which details remain unclear. After this operation, the patient developed the symptoms of left median nerve injury. Thus, he came to our hospital and underwent a second operation. During this operation, we found that a part of the median nerve was absent at the left forearm, and the remanent median nerve, from the broken end to the elbow, was totally turned black, which was accompanied by petroleum-like exudate. Losing the opportunity for nerve repair, the black nerve was removed extensively and thoroughly. Postoperative pathological diagnosis revealed that the tumor was melanotic schwannoma. Then 4 years later, the tumor recurrence again, which led to the paralysis of the whole left arm and severe nerve pain, and the pulmonary metastasis of the tumor was detected at the same time. The black nerve was resected again in our hospital, and the nerve pain was partially relieved after the operation. To the best of our knowledge, it is the first time to report a melanotic schwannoma case that happened in the peripheral nerve trunk and then spread to the whole brachial plexus. There were many questions that worthy of discussion could be invited from this case, and we analyzed and discussed them based on the relevant literature. In conclusion, we reported a rare case of melanotic schwannoma that happened in the brachial plexus and illustrated the problems of the diagnosis and treatment of it based on the analysis of the relevant literature, which is helpful for the cognition of this rare nerve tumor.

Clinical outcomes of a novel porcine small intestinal submucosa patch for full-thickness hand skin defects: a retrospective investigation

OBJECTIVE

To investigate the clinical outcomes of a novel soft tissue repair patch (porcine small intestinal submucosa patch, SIS patch) in the treatment of full-thickness hand skin defects.

METHODS

From January 2017 to July 2019, 80 patients with hand soft tissue defects, who met the inclusion criteria, were retrospectively reviewed and divided into two groups. After debridement, patients in group A were treated with the novel SIS patch to cover the wound, and patients in group B were treated with autologous skin graft. The dimensions of skin defect area and healing outcome were evaluated and recorded. Scar assessment was carried out using Scar Cosmesis Assessment and Rating Scale (SCAR scale) at the last follow-up postoperation, and the recovery of wound sensation was assessed at the same time using British Medical Research Council (BMRC) grading of sensorimotor recovery. All the data were collected and statistically analyzed.

RESULTS

A total of 80 patients were enrolled in the study with 40 patients in each group. Four patients in group A and 5 patients in group B were excluded due to wound infection and lost to follow-up. There were 36 patients in group A and 35 patients in group B finally got follow-up postoperation with mean interval of 12.75 ± 5.61 months in group A and 14.11 ± 5.42 months in group B. The dimensions of skin defect area in group A ranged from 7.5 to 87.5 cm² (mean 25.97 ± 18.66 cm²) and in group B ranged from 7.5 to 86.25 cm² (mean 33.61 ± 19.27 cm²) which have no significant difference (P > 0.05). SCAR scale results of group A and group B were 10.98 ± 0.33 and 9.49 ± 0.35, respectively, and the difference was statistically significant (P < 0.05). BMRC grading results showed 6 cases of S4, 11 cases of S3+, 5 cases of S3, 6 cases of S2, 6 cases of S1 and 2 cases of S0 in group A, and 8 cases of S4, 10 cases of S3+, 7 cases of S3, 4 cases of S2, 5 cases of S1, and 1 case of S0 in group B, which had no significant difference between them (P > 0.05).

CONCLUSIONS

The novel SIS patch is an applicable biological material in the treatment of hand skin defect, which could achieve a better cosmetic appearance of the newborn skin tissue.

DNA polymerase β may be involved in protecting human bronchial epithelial cells from the toxic effects induced by methyl tert-butyl ether exposure

Methyl tert-butyl ether (MTBE), a widely used gasoline additive and a ubiquitous environmental pollutant in many countries and regions, can cause various kinds of toxic effects on human health. However, the molecular mechanism underlying its toxic effects remains elusive. The present study aimed to explore the cytotoxicity, DNA damage and oxidative damage effects of MTBE on human bronchial epithelial cells (16HBE) and the possible role of DNA polymerase β (pol-β) in this process. RNA interference (RNAi) was used to obtain pol-β gene knocked-down cells (pol-β^-). CCK-8 assay was adopted to analyze the cell viability. Alkaline single-cell gel electrophoresis (SCGE) was performed to detect the DNA damage effects of MTBE. The enzyme activity of GSH-Px, SOD, CAT and the level of MDA were assessed. The data indicated that when treated with MTBE at the concentration exceeding 50 μmol/L and for the time exceeding 24 h, the pol-β^- exhibited significantly decreased cell viability and increased DNA damage effects, as compared to the control (P < 0.05). Furthermore, there was significant difference in the levels of GSH-pX, SOD, CAT and MDA between the pol-β^- and the control (P < 0.05). Our investigation suggests that MTBE can cause obvious cytotoxicity, DNA damage and oxidative damage effects on 16HBE cells. DNA polymerase β may be involved in protecting 16HBE cells from the toxic effects induced by MTBE exposure. These findings provide a novel insight into the molecular mechanism underlying the toxic effects of MTBE on human cells.

AB0128 CONSTRUCTION OF THE VETERANS AFFAIRS NATIONAL RHEUMATOID ARTHRITIS DATABASE (VANRAD)

Background:

The Department of Veterans Affairs (DVA) provides comprehensive medical care at minimal or no cost to 9 million veterans annually through 170 medical centers and 1074 outpatient clinics across the United States. In 1999, the DVA established a national, fully integrated electronic health record (EHR), which now includes approximately 24 million veterans. However, few studies have used VA EHR data to examine the validity of diagnoses of rheumatoid arthritis (RA).

Objectives:

Develop a validated, national database (VANRAD) of patients with RA who received VA care since International Classification of Diseases, tenth revision (ICD-10) coding was introduced in 2015. The database will provide infrastructure for retrospective and prospective research to address the ‘real-world’ care of patients with RA.

Methods:

Patients with the following criteria were identified from the VA EHR as of October 2, 2020: (a) ≥1 ICD-10 diagnosis code of RA; (b) treatment with ≥1 disease-modifying anti-rheumatic drug (DMARD); (c) ≥2 VA rheumatology clinic visits; and (d) ≥1 rheumatoid factor (RF) or anti-cyclic citrullinated peptide (aCCP) antibody test result. From this group, 553 EHRs were randomly selected for review. The ‘gold standard’ for the diagnosis of RA was the treating rheumatologist’s diagnosis, documented in the EHR.

Results:

27,482 patients met eligibility criteria. Sociodemographic characteristics were: 85.6% male, mean age of 69.7 years (y) (SD=10.9 y; range=21.9 y to 100.5 y), 76.4% white, 17.0% African American; and mean VA care duration 14.1 y (SD=5.3 y, range=0.04 y to 20.0 y).

For patients with ≥1 RF or aCCP test, the positive predictive value (PPV) for RA ranged from 65.3% (aCCP-/RF-) to 95.8% (aCCP+/RF+); rheumatologists’ likelihood of a ‘possible’ diagnosis was higher if the aCCP test result was negative or not available (Table 1). Excluding patients with a second rheumatologic diagnosis did not improve PPV results (data not shown).

Table 1.

Proportion of patients with a valid RA diagnosis1 as a function of RF and aCCP laboratory results

Test ResultaCCPNot Available (0)2Negative (-)Positive (+)TotalRheumatoid FactorNot Available (0)(N = 1253)3N 427N 1,159N 1,586RA4 89.7%RA 98.2%RA 93.5%Poss5 RA 5.9%Poss RA 0.0%Poss RA 3.2%Negative (-)N 810N 5,308N 2,005N 8,123RA 86.3%RA 65.3%RA 94.5%RA 80.7%Poss RA 3.9%Poss RA 11.9%Poss RA 0.0%Poss RA 5.8%Positive (+)N 2,229N 2,566N 12,978N 17,773RA 94.6%RA 78.0%RA 95.8%RA 87.6%Poss RA 0.0%Poss RA 8.5%Poss RA 2.1%Poss RA 4.3%TotalN 3,039N 8.301N 16,142N 27,482RA 90.7%RA 76.1%RA 95.9%RA 85.9%Poss RA 1.9%Poss RA 9.2%Poss RA 0.5%Poss RA 4.7%

1Diagnosis given by the treating rheumatologist.

2No test results available or test results available but without normal range values.

31,253 patients without available or interpretable RF or aCCP excluded from initial cohort.

4Percent of 553 charts reviewed confirmed as RA.

5Poss RA = Possible RA. Patients met our inclusion criteria but the treating rheumatologist never made definitive diagnosis of RA or alternative diagnosis (from 553 charts reviewed).

The percentage of RA-confirmed patients with one test not available, whose complementary test was negative (RF0/aCCP- or RF-/aCCP0), was greater than of patients for whom both tests were negative (RF-/aCCP-). This suggests our data extraction methods may be incomplete or that unidentified bias may be present and warrants further study.

Conclusion:

Our methodology for constructing an RA database by selecting patients with ≥2 rheumatology clinic visits, ≥1 ICD-10 diagnosis of RA, and treatment with ≥1 DMARD, has high positive predictive value for RA. Positive RF and aCCP test results were strong predictors of rheumatologists’ diagnostic certainty for an RA diagnosis. Thus, the VANRAD database and the associated EHR provide opportunity for a wide range of retrospective observational and prospective longitudinal studies based on ‘real-world’ patient care.

References:

[1]Ng B, et al. Arthritis Care Res 2012;64:1490-6; Hanly JG, et al. Open Access Rheumatol 2015;7:69-75.

Acknowledgements:

This study was sponsored by Bristol Myers Squibb.

Disclosure of Interests:

Amy Joseph Speakers bureau: Speakers bureau in the distant past., Grant/research support from: Bristol Myers Squibb, Jodi Yanagida: None declared, Xinliang Huang: None declared, Prabha Ranganathan: None declared, Melissa Laurie Shareholder of: Bristol-Myers Squibb, Employee of: I am currently employed by Bristol Myers Squibb., Hong Xian Grant/research support from: Bristol Myers Squibb Co., Seth Eisen Grant/research support from: The effort presented in this Abstract was supported with funds provided by Bristol-Meyers Squibb.

Frog leg lateral view is a reliable predictor of the prognosis in osteonecrosis of the femoral head

The location and size of necrotic lesions are primary factors that predict the prognosis in osteonecrosis of the femoral head (ONFH). The Japanese Investigation Committee (JIC) classification system, based on the location of the necrotic lesion, has been widely accepted and applied around the world. However, there is no report about whether the location of the necrotic area in lateral view may affect the prognosis predicted initially by the JIC classification. The purpose of this study was to investigate whether the location of the necrotic area in the frog leg lateral (FL) view would affect the prediction of prognosis for patients with ONFH. We retrospectively studied 90 hips in 76 patients with ONFH (Ficat stage I to II) after a mean follow-up of 35.3 months. All patients received standard radiographs including an anteroposterior (AP) and a FL view of the affected hip. The percentage of the necrotic area (necrotic area/whole femoral head area) was measured and compared between AP and FL view. Hips with ONFH were categorized using the JIC classification and the FL view type system, and inter- and intraobserver reliability was compared between them. All patients underwent personalized hip physiotherapy, and the cumulative survival rate with subsequent collapse and/or requirement for further hip surgery as the endpoints was evaluated for the two classification systems. The percentage of the necrotic area was found to be significantly greater in the FL views (47.0 ± 1.5%) than that in the AP views (37.7 ± 1.7%, P < .01). Intraobserver reliability in the JIC classification (mean: 0.91, range: 0.85-0.98) was higher than that in the FL view type (mean: 0.77, range: 0.63-0.89; P < .01), as well as the interobserver reliability in the JIC classification (mean: 0.74, range: 0.38-0.87) was higher than that in the FL view type (mean: 0.58, range: 0.31-0.76; P < .01). Comparisons of survival curves showed that type III in FL view type had the worst prognosis than other two divisions, following the type II. The type I was likely to gain optimal outcomes. These findings provide evidence that the location to which necrosis extended in the FL view is a reliable indicator in predicting the prognosis of ONFH.

[NEK2 gene expression in mouse cryptorchidism model and its mechanism involved in apoptosis]

Objective: To observe the expression of NEK2 mRNA and protein in the cryptorchidism mice model, and to explore its role in apoptosis of testicular tissue. Methods: A mouse cryptorchid model was constructed, and the spermatids in the spermatic tubules were observed by HE staining. Apoptosis was detected by Tunel test, and expression of NEK2 mRNA and protein was detected by RT-PCR and immunohistochemistry, respectively. Results: After the mouse cryptorchidism model was successfully constructed, the HE staining results showed that the damage of spermatogonia cells, primary spermatocytes and sperm cells in the seminiferous tubules became more severe with time. The results of Tunel test showed that the number of apoptotic cells first increased and then decreased, 1, 3, 6, 9 and 15 d apoptotic cells were 3.67±2.08 (t=2, P=0.0412), 7.67±1.53 (t=6.325, P=0.003), 17.67±3.51 (t=7.906, P=0.001), 30.67±3.51 (t=14.072, P<0.001) and 14.33±3.21 (t=6.860, P=0.002). The results of immunohistochemistry showed that NEK2 protein was expressed in the nucleus and cytoplasm in normal testis and cryptorchidism. RT-PCR and immunohistochemistry showed that expression of NEK2 mRNA and protein gradually increased after modeling. After reaching the peak, the expression gradually decreased with time, and was significantly lower than the normal control group. Conclusion: The trend of NEK2 expression in cryptorchidism tissue is consistent with the trend of cell apoptosis in cryptorchidism tissue, suggesting that abnormal expression of NEK2 may affect the damage of sperm cells in the seminiferous tubules through apoptosis, leading to infertility in patients with cryptorchidism.

CCL2 facilitates spinal synaptic transmission and pain via interaction with presynaptic CCR2 in spinal nociceptor terminals

Previous studies have shown that CCL2 may cause chronic pain, but the exact mechanism of central sensitization is unclear. In this article, we further explore the presynaptic role of CCL2. Behavioral experiments show that intervertebral foramen injection CCR2 antagonists into dorsal root ganglion (DRG) can inhibit the inflammatory pain caused by CCL2 in spinal cord. We raised the question of the role of presynaptic CCR2 in the spinal dorsal horn. Subsequent electron microscopy experiments showed that CCR2 was expressed in the presynaptic CGRP terminal in the spinal dorsal horn. CCL2 can enhance presynaptic calcium signal. Whole-cell patch-clamp recordings showed that CCL2 can enhance NMDAR-eEPSCs through presynaptic effects, and further application of glutamate sensor method proved that CCL2 can act on presynaptic CCR2 to increase the release of presynaptic glutamate. In conclusion, we suggest that CCL2 can directly act on the CCR2 on presynaptic terminals of sensory neurons in the spinal dorsal horn, leading to an increase in the release of presynaptic glutamate and participate in the formation of central sensitization.

Platelet-Rich Plasma-Incorporated Autologous Granular Bone Grafts Improve Outcomes of Post-Traumatic Osteonecrosis of the Femoral Head

BACKGROUND

To investigate the effects of platelet-rich plasma (PRP)-incorporated autologous granular bone grafts for treatment in the precollapse stages (Association of Research Circulation Osseous stage II-III) of posttraumatic osteonecrosis of the femoral head.

METHODS

A total of 46 patients were eligible and enrolled in the study. Twenty-four patients were treated with core decompression and PRP-incorporated autologous granular bone grafting (treatment group), and 22 patients were treated with core decompression and autologous granular bone grafting (control group). During a minimum follow-up duration of 36 months, X-ray and computed tomography were used to evaluate the radiological results, and the Harris hip score (HHS) and visual analog scale were chosen to assess the clinical results.

RESULTS

Both the treatment and control groups had a significantly improved HHS (P < .001). The minimum clinically important difference for the HHS was reached in 91.7% of the treatment group and 68.2% of the control group (P < .05). The HHS and visual analog scale in the treatment group were significantly improved than that in the control group at the last follow-up (P < .05). Successful clinical and radiological results were achieved 87.5% and 79.2% in the treatment group compared with 59.1% and 50.0% in the control group (P < .05), respectively. The survival rates based on the requirement for further hip surgery as an endpoint were higher in the treatment group in comparison to those in the control group (P < .05).

CONCLUSION

PRP-incorporated autologous granular bone grafting is a safe and effective procedure for treatment in the precollapse stages (Association of Research Circulation Osseous stage II-III) of posttraumatic osteonecrosis of the femoral head.

Clinicopathological and prognostic value of hypoxia-inducible factor-1α in patients with bone tumor: a systematic review and meta-analysis

Background

Recently, many studies have shown the role of hypoxia-inducible factor-1α (HIF-1α) expression in the outcome of bone tumor. However, the results remain inconclusive. It is necessary to carry out a meta-analysis of all the current available data to clarify the relationship between HIF-1α and survival or clinicopathological features of bone tumor.

Methods

PubMed, Cochrane Library, Web of Science, China National Knowledge Internet, and Wanfang databases were used to search the relationship between HIF-1α and bone tumor. Articles investigating clinicopathological and prognostic value of HIF-1α in bone tumor patients were enrolled in this meta-analysis. Overlapping articles, duplicate data, reviews, case reports, and letters without original data were excluded. The pooled risk ratios (RRs) and hazard ratios (HRs) were used to evaluate the clinicopathological and prognostic value of HIF-1α on bone tumor patients, respectively.

Results

A total of 28 studies including 1443 patients were included in this meta-analysis, which were involved in three different types of bone tumor including 3 chondrosarcomas, 2 giant cell tumors of bone, and 23 osteosarcomas. Our results showed that high expression levels of HIF-1α were associated with poorer OS (overall survival) (HR = 2.61, 95% CI 2.11–3.23, P <  0.001) and shorter DFS (disease-free survival) (HR = 2.02, 95% CI 1.41–2.89, P <  0.001) in bone tumor. In addition, this study also analyzed the role of HIF-1α expression in clinicopathological features, which were closely related with the severity of bone tumor, including differentiation, clinical stage, metastasis, and microvessel density. Our results indicated that HIF-1α overexpression was significantly associated with differentiation (RR = 1.56, 95% CI 1.00–2.43, P = 0.049), clinical stage (RR = 1.75, 95% CI 1.25–2.45, P = 0.001), metastasis (RR = 1.78, 95% CI 1.58–2.00, P <  0.001), and microvessel density (SMD = 2.34, 95% CI 1.35–3.34, P <  0.001) of bone tumor.

Conclusions

HIF-1α overexpression indicated an unfavorable factor for OS and DFS in bone tumor, suggesting that HIF-1α may serve as a potential prognostic marker for bone tumor.

Electronic supplementary material

The online version of this article (10.1186/s13018-019-1101-5) contains supplementary material, which is available to authorized users.

Revisiting the low birthweight paradox using sibling data with implications for the classification of low birthweight

Background

We examined the birthweight threshold for increased odds of neonatal death among second births based on their elder sibling's birthweight category.

Methods

This population-based cohort study included 190 575 women who delivered their first two non-anomalous singleton live births in Missouri (1989-2005). We examined the birthweight distribution and neonatal mortality curves of second births whose elder sibling had low versus adequate/high birthweight. We determined the optimal cut-off point for the classification of low birthweight among infants in each group based on the Youden index.

Results

Infants whose elder sibling had low birthweight had a lower mean birthweight and a higher percentage of low birthweight infants versus those whose elder sibling had adequate/high birthweight, but low birthweight infants in the former group had a lower rate of neonatal mortality. Upon standardizing the birthweight distribution to a Z-scale, neonatal mortality rates became comparable between the two groups at every rescaled birthweight for Z-scores ≥-3.7. The optimal cut-off point for low birthweight was 2500 and 3000 g among infants whose elder sibling had low and adequate/high birthweight, respectively.

Conclusions

Using sibling data for the classification of LBW may enable the identification of average-sized infants who may be at increased risk of neonatal mortality.

A special superior cortex compressive fracture of femoral neck: Two case reports

RATIONALE

Garden type I femoral neck fractures are incomplete stable fractures with impaction in valgus fractures that the question of whether there exists Garden type I femoral neck fracture is currently uncertain. There is still disagreement on the existence of the Garden type I fractures.

PATIENT CONCERNS

Herein we report 2 cases with the Garden type I femoral neck fractures. Both of them had a history of simple fall.

DIAGNOSES

The X-ray showed incomplete fractures of the femoral neck and the Garden classification is type I. Further computed tomography and magnetic resonance imaging were used to confirm the diagnosis of this type fracture, which showed that the superior cortex of femoral neck was discontinuous and the inferior cortex remains intact.

INTERVENTIONS

The conservative treatment schedule including immobilization of the affected lower limb, strict bed rest, bed-to-wheelchair transfer training, and half-to-full weight bearing mobilization were chosen to treat the patients.

OUTCOMES

Both of them achieved fracture union with conservative treatment at 3-month follow-up. No secondary displacement, signal of osteonecrosis of the femoral head or other complications occurred during 24-month follow-up in 2 cases.

LESSONS

Although the Garden type I femoral neck fractures are rare, our report is in line with the real existence of it.

Novel Elastic Syndesmosis Hook Plate Fixation Versus Routine Screw Fixation for Syndesmosis Injury

Unstable external-rotation type ankle fractures with concomitant syndesmosis injury commonly occur. Syndesmosis screw fixation has long been regarded as a reference standard treatment for syndesmosis injury. However, its complications and biomechanical disadvantages have become controversial; thus, we designed a novel elastic syndesmosis hook plate (ESHP) that combines the features of both rigidity and flexibility. The purpose of the present study was to introduce this new method and compare its clinical outcomes with those of routine screw fixation. We randomized 25 patients to the screw fixation group and ESHP group. The average follow-up period was 12 months. The clinical outcomes included malreduction or loss of reduction, overall complications, and function. During the follow-up period, 3 cases (25%) of malreduction were found in screw fixation group on postoperative computed tomography. In the ESHP group, only 1 patient (7.69%) had a narrowed anterior gap between the distal tibia and fibula. However, the difference in the malreduction rate between the 2 groups was not significant statistically (p = .32). The overall complication rate in the ESHP group was lower than that in the screw group, although no significant differences were found between the 2 groups. The mean visual analog scale scores in the ESHP and screw groups were 1.46 ± 1.33 and 2.42 ± 2.07, respectively. The average dorsiflexion range of motion in both groups was satisfactory (14.77° versus 12.83°; p = .16). However, a statistically significant difference was found in the plantarflexion range of motion between the 2 groups (p < .05). In addition, the ESHP group had an earlier time to return to work (p < .05). The ESHP fixation construct can stably fix syndesmosis, retain the physiologic micromotion function of the syndesmosis, and results in fewer complications compared with routine syndesmosis screw fixation for syndesmotic instability. In conclusion, our results have shown ESHP to be a viable method for treatment of syndesmosis instability.

Examining the relationships between life satisfaction and alcohol, tobacco and marijuana use among school-aged children

Background

There are many known risk factors associated with youth substance use. Nonetheless, the impact of life satisfaction (LS) on the use of alcohol, tobacco and marijuana by adolescents still remains largely unknown.

Methods

The present analysis utilized data from the Health Behavior in School-Aged Children 2009–10 US study. Multilevel logistic regression models were used to assess the relationship between LS and individual substance use. Multilevel multinomial regression models examined the relationship with total number of substances used.

Results

After controlling for numerous variables associated with substance use, individuals reporting low LS were significantly more likely to ever use tobacco (OR = 1.34, 95% CI = [1.01, 1.78]), alcohol (OR = 1.45, 95% CI = [1.10, 1.92]) and marijuana (OR = 1.98, 95% CI = [1.39, 2.82]). Additionally, students with low LS were significantly more likely to use two substances (OR = 1.90, 95% CI = [1.15, 3.14]) and three substances concurrently (OR = 2.00, 95% CI = [1.27, 3.16]).

Conclusions

The present study identified strong associations between LS and individual, as well as concurrent, substance use among adolescents. Interventions aiming to reduce adolescent substance use may benefit from incorporating components to improve LS.

Salmonella potsdam causing lumbar vertebral osteomyelitis: A case report

RATIONALE

Salmonella osteomyelitis is an uncommon complication of salmonella infection, especially the salmonella vertebral osteomyelitis (SVO).

PATIENT CONCERNS

We reported a case of a 29-year-old female who presented with serious lower back pain and severe limitation of motion for 50 days with no obvious inducements. She once had a fever up to 39.5°C. Physical examination only revealed limited motion of lower back without neurological complications. The laboratory results revealed no specificity. MRI of the lumbar spine revealed a spondylodiscitis at L4-L5. She underwent anterior lateral approach debridement and percutaneous posterior instrumentation.

DIAGNOSES

Tissue and abscess culture grew showed Salmonella Potsdam infection.

INTERVENTIONS

With susceptibility testing guidance, the patient was treated with intravenous levofloxacin and ceftazidime for a period of 3 weeks and another 3-week oral antibiotics therapy.

OUTCOMES

The patient recovered well with no neurological deficits during the follow-up time.

LESSONS

SVO is really rare and it alerts us the importance to consider uncommon pathogens in the differential diagnosis in which the etiological evidences are crucial of healthy individuals.

Spontaneous spinal epidural hematomas: One case report and rehabilitation outcome

RATIONALE

Spontaneous spinal epidural hematoma (SSEH) is a relatively rare but potentially disabling disease, and the classical presentation of it includes an acute onset of severe, sometimes radiating back or neck pain, followed by signs and symptoms of rapidly evolving nerve root or spinal cord compression.

PATIENT CONCERNS

Here, we report a 26-year-old female patient presented with weakness in bilateral lower extremities, progressing to intense paraplegia and anesthesia without recent medical history of trauma, infection, surgery, or drug use.

DIAGNOSIS

A magnetic resonance imaging (MRI) scan of spinal cord was planned and a posterior epidural hematoma of the thoracic spine was observed.

INTERVENTIONS

A posterior decompression and hematoma evacuation was performed after diagnosis immediately. Early rehabilitation program of the specific kind spinal cord injury was formulated and implemented.

OUTCOMES

The patient finally can handle basic living activities, such as completing wheelchair locomotion, transferring from bed to wheelchair independently after 3 months of rehabilitation.

LESSONS

SSEH is a rarely occurring case in emergency. Acute chest pain and paraplegia could be the initial presentation of acute spinal epidural hemorrhage, but the diagnosis of patient without classical manifestations is still a challenge for doctors. Early diagnosis, prompt decompression, and individualized rehabilitation program can improve the prognosis and outcome.

Modified dynamic hip screw loaded with autologous bone graft for treating Pauwels type-3 vertical femoral neck fractures

INTRODUCTION

Management of Pauwels type-3 vertical femoral neck fractures has been a challenging clinical problem as they experience high shear forces and thus a greater risk of treatment failure. There is no apparent consensus on the optimal implant type for these injuries. We developed a modified dynamic hip screw (DHS), which was designed to a cage in the lag screw, loaded with autologous bone graft for the treatment of Pauwels type-3 vertical femoral neck fractures.

METHODS

Between February 2010 and January 2012, 17 consecutive patients with Pauwels type-3 vertical femoral neck fractures were treated with the modified DHS loaded with autologous bone graft. All patients were followed up for a minimum of 24 months (range, 24-36 months). Surgical details, operative and postoperative complications, the rates of nonunion and osteonecrosis and the Harris hip score were evaluated.

RESULTS

There were thirteen men and four women with a mean age of 37.2 years (range, 27-52 years). There were no intraoperative complications related to this technology. All fractures healed within 14.1 weeks (range, 12 to 20 weeks). One patient required total hip replacement because of avascular necrosis of the femoral head at 27 months after surgery. According to the Harris hip score, eleven patients (64.7%) had excellent results, four (23.5%) had good results, one (5.9%) had moderate and one (5.9%) had poor result.

CONCLUSIONS

The modified DHS loaded with autologous bone graft appears to be a reliable implant for the treatment of Pauwels type-3 vertical femoral neck fractures with fewer complications.

The upregulation of pro-inflammatory cytokines in the rabbit uterus under the lipopolysaccaride-induced reversible immunoresponse state

The reproductive organs are more likely to develop gram-negative bacterial infection than other internal organs because of direct access to the body surface. The objective of this study was (1) to provide a suitable intravenous injection dose of lipopolysaccharides (LPS) instead of gram-negative bacterial infection in order to induce a reversible immunoresponse state and (2) to examine the expression levels of pro-inflammatory cytokines in the uterus of rabbits while in an immunoresponse state. Two series of experiments were performed to accomplish these objectives. In the first series, 20 healthy New Zealand White female rabbits were divided into 5 homogeneous groups (n=4), and intravenously injected with 0, 0.5, 1, 2, or 4mg/kg body weight (BW) of LPS derived from Escherichia coli dissolved in 2ml of sterile saline (LPS carrier). The control group received only saline. The concentrations of IL-1β, IL-6, and TNF-α in serum and the white blood cell count changed with time after LPS stimulation, and certain doses of LPS led to the death of some rabbits. The results suggested that a dose of 0.5mg/kg of LPS induced a reversible immunoresponse state. In the second series, 4 rabbits were not injected (0h), 16 rabbits were injected with 0.5mg/kg LPS, and 16 rabbits in the control group were injected with 2ml of sterile saline. Tissues of the uterine horn, uterine body, and cervix from the 36 rabbits were collected at 0, 1.5, 3, 6, and 12h (n=4) postinjection for examination of the expression levels of IL-1β, IL-6, and TNF-α by quantitative real-time PCR (qRT-PCR). The results suggested that 0.5mg/kg of LPS upregulated the expression levels of IL-1β, IL-6 and TNF-α in the uterine body and uterine horn, and IL-6 in the cervix. In conclusion, the expression levels of IL-1β, IL-6 and TNF-α were upregulated in the uterus of rabbits under the reversible immunoresponse state induced by 0.5mg/kg of LPS-injection.

Risk factors and clinical outcomes for carbapenem-resistant Enterobacteriaceae nosocomial infections

This study was aimed to determine the risk factors of Carbapenem-resistant Enterobacteriaceae (CRE) nosocomial infections and assess the clinical outcomes. A case-case-control design was used to compare two groups of case patients with control patients from March 2010 to November 2014 in China. Risk factors for the acquisition of CRE infections and clinical outcomes were analyzed by univariable and multivariable analysis. A total of 94 patients with CRE infections, 93 patients with Carbapenem-susceptible Enterobacteriaceae (CSE) infections, and 93 patients with organisms other than Enterobacteriaceae infections were enrolled in this study. Fifty-five isolates were detected as the carbapenemase gene. KPC-2 was the most common carbapenemase (65.5 %, 36/55), followed by NDM-1 (16.4 %, 9/55), IMP-4 (14.5 %, 8/55), NDM-5 (1.8 %, 1/55), and NDM-7 (1.8 %, 1/55). Multivariable analysis implicated previous use of third or fourth generation cephalosporins (odds ratio [OR], 4.557; 95 % confidence interval [CI], 1.971-10.539; P < 0.001) and carbapenems (OR, 4.058; 95 % CI, 1.753-9.397; P = 0.001) as independent risk factors associated with CRE infection. The in-hospital mortality of the CRE group was 57.4 %. In the population of CRE infection, presence of central venous catheters (OR, 4.464; 95 % CI, 1.332-14.925; P = 0.015) and receipt of immunosuppressors (OR, 7.246; 95 % CI, 1.217-43.478; P = 0.030) were independent risk factors for mortality. Appropriate definitive treatment (OR, 0.339; 95 % CI, 0.120-0.954; P = 0.040) was a protective factor for in-hospital death of CRE infection. Kaplan-Meier curves of the CRE group had the shortest survival time compared with the other two groups. Survival time of patients infected with Enterobacteriaceae with a high meropenem MIC (≥8 mg/L) was shorter than that of patients with a low meropenem MIC (2,4, and ≤ 1 mg/L). In conclusion, CRE nosocomial infections are associated with prior exposure to third or fourth generation cephalosporins and carbapenems. Patients infected with CRE had poor outcome and high mortality, especially high meropenem MIC (≥8 mg/L). Appropriate definitive treatment to CRE infections in the patient is essential.

Testosterone modifies the effect of APOE genotype on hippocampal volume in middle-aged men

BACKGROUND

The APOE epsilon4 allele is an established risk factor for Alzheimer disease (AD), yet findings are mixed for how early its effects are manifest. One reason for the mixed results could be the presence of interaction effects with other AD risk factors. Increasing evidence indicates that testosterone may play a significant role in the development of AD. The aim of the present study was to examine the potential interaction of testosterone and APOE genotype with respect to hippocampal volume in middle age.

METHODS

Participants were men from the Vietnam Era Twin Study of Aging (n = 375). The mean age was 55.9 years (range 51-59). Between-group comparisons were performed utilizing a hierarchical linear mixed model that adjusted for the nonindependence of twin data.

RESULTS

A significant interaction was observed between testosterone and APOE genotype (epsilon4-negative vs epsilon4-positive). Those with both low testosterone (> or =1 SD below the mean) and an epsilon4-positive status had the smallest hippocampal volumes, although comparisons with normal testosterone groups were not significant. However, individuals with low testosterone and epsilon4-negative status had significantly larger hippocampal volumes relative to all other groups. A main effect of APOE genotype on hippocampal volume was observed, but only when the APOE-by-testosterone interaction was present.

CONCLUSIONS

These findings demonstrate an interaction effect between testosterone and the APOE epsilon4 allele on hippocampal volume in middle-aged men, and they may suggest 2 low testosterone subgroups. Furthermore, these results allude to potential gene-gene interactions between APOE and either androgen receptor polymorphisms or genes associated with testosterone production.

Apolipoprotein E genotype and memory in the sixth decade of life

BACKGROUND

Virtually all adult studies of APOE genotypes and cognition have included individuals over 60. In older adults, epsilon 4 carriers may manifest greater cognitive asymmetries than non-epsilon 4 carriers even in the absence of overall mean differences. General cognitive ability may also be affected by aging and APOE genotype, but most studies have inadequately addressed this potential confound. The goals of this study were to examine, in middle age, the relationship of APOE genotype with episodic memory and verbal-visuospatial episodic memory asymmetries, after accounting for prior general cognitive ability.

METHOD

We compared epsilon 4+ and epsilon 4- individuals in 626 male twins in their 50s. We examined verbal and visuospatial episodic memory and verbal-visual asymmetry scores after adjusting for cognitive ability at age 20. Analyses corrected for correlations between twin pair members.

RESULTS

Compared with epsilon 4- individuals, epsilon 4 carriers performed significantly more poorly on verbal, but not visuospatial memory, manifested significantly greater cognitive asymmetry, and also had significantly more concerns about memory. At age 20, epsilon 4 carriers had higher general cognitive ability than epsilon 4- individuals, and current memory differences were enhanced after adjusting for age 20 cognitive ability.

CONCLUSIONS

Small, but significant, APOE-epsilon 4-related memory deficits appear in the sixth decade of life in individuals who show no signs of preclinical dementia. The results partially support studies of older adults that suggest that increased cognitive asymmetries reflect risk for dementia and are associated with the APOE-epsilon 4 genotype. The results also highlight the potential problems of not having accurate data on prior cognitive ability.

Neuropsychological consequences of regular marijuana use: a twin study

BACKGROUND

Results of previous research examining long-term residual effects of marijuana use on cognition are conflicting. A major methodological limitation of prior studies is the inability to determine whether differences between users and non-users are due to differences in genetic vulnerability preceding drug use or due to the effects of the drug.

METHOD

Fifty-four monozygotic male twin pairs, discordant for regular marijuana use in which neither twin used any other illicit drug regularly, were recruited from the Vietnam Era Twin Registry. A minimum of 1 year had passed since the marijuana-using twins had last used the drug, and a mean of almost 20 years had passed since the last time marijuana had been used regularly. Twins were administered a comprehensive neuropsychological test battery to assess general intelligence, executive functioning, attention, memory and motor skills. Differences in performance between marijuana-using twins and their non-using co-twins were compared using a multivariate analysis of specific cognitive domains and univariate analyses of individual test scores. Dose response relationships were explored within the marijuana-using group.

RESULTS

Marijuana-using twins significantly differed from their non-using co-twins on the general intelligence domain; however, within that domain only the performance of the block design subtest of the Wechsler Adult Intelligence Scale--Revised reached a level of statistical significance.

CONCLUSIONS

Out of the numerous measures that were administered, only one significant difference was noted between marijuana-using twins and their non-using co-twins on cognitive functioning. The results indicate an absence of marked long-term residual effects of marijuana use on cognitive abilities.

A twin study of generalized anxiety disorder symptoms, panic disorder symptoms and post-traumatic stress disorder in men

Generalized anxiety disorder (GAD), panic disorder (PD) and post-traumatic stress disorder (PTSD) often co-occur. We investigated whether and to what degree genetic and environmental contributions overlap among symptoms of GAD, symptoms of PD and PTSD. Subjects were 3327 monozygotic and dizygotic male-male twin pair members of the Vietnam Era Twin Registry who participated in a 1992 telephone administration of the Diagnostic Interview Schedule Version 3 Revised (DIS3R). Genetic model fitting was performed to estimate the magnitude of genetic and environmental contributions to the lifetime co-occurrence of GAD symptoms, PD symptoms and PTSD. The liability for GAD symptoms was due to a 37.9% additive genetic contribution common to PD symptoms and PTSD. Liability for PD symptoms was due to a 20.7% additive genetic contribution common to GAD symptoms and PTSD, and a 20.1% additive genetic influence specific to PD symptoms. Additive genetic influences common to symptoms of GAD and PD accounted for 21.3% of the genetic variance in PTSD. Additive genetic influences specific to PTSD accounted for 13.6% of the genetic variance in PTSD. Remaining variance for all three disorders was due to unique environmental factors both common and specific to each phenotype. These results suggest that these disorders each have etiologically distinct components and also have significant genetic and unique environmental contributions in common.

[Immobilization of penicilin G acylase on polyacrylonitrile fiber]

The immobilization of Penicillin G Acylase from Bacillus megaterium by glutaraldehyde crosslinking on the partially acid-hydrolyed polyacrylonitrile fiber was studied. When the amount of--NH2 on fiber were 690 mumol/g and the moisture in the fiber was 64%, and the content of enzyme protein immobilized on fiber was more than 100 mg/g. The activity of 2300 IU/g was obtained with 30% of overall yield and 56% of binding efficiency. The immobilization yield was markedly influenced by ratio of the amount of free enzyme used to the weight of the fiber. The half-life of storage stability of immobilized PGA at room temperature was 130 days. The immobilized PGA kept 80% of the initial activity after 20 cycles of operation in 10% of PGK(W/V) in 0.05 mol/L phosphate buffer, pH 8.0, at 37 degrees C and an enzyme load of 150 IU/g(PGK) and 10 g(PGK) for per cycle of operation. The hydrolysis conversion of PGK in the range of 2.5%-12.5% (W/V) were over 98% for the immobilized PGA. The operation stability of immobilized PGA treated with DTT was better than that of immobilized PGA untreated.

A twin study of the association between pathological gambling and antisocial personality disorder

Many individuals with a history of pathological gambling (PG) also have a history of engaging in antisocial behaviors, and this has often been interpreted as a result of the former causing the latter. In a sample of 7,869 men in 4,497 twin pairs from the Vietnam Era Twin Registry, the authors examined (a) the association between PG and antisocial personality disorder (ASPD), (b) the extent to which PG might be differentially associated with childhood conduct disorder (CD) and adult antisocial behavior (AAB), and (c) the contribution of genetic and environmental factors to the association of PG with ASPD, CD, and AAB. PG was significantly associated with all 3 antisocial behavior disorders, and the association of PG with ASPD, CD, and AAB was predominantly explained by genetic factors. The results of this study suggest that the greater-than-chance co-occurrence of PG and antisocial behavior disorders is partially due to their sharing a common genetic vulnerability. The antisocial behavior observed among many individuals with PG probably cannot be interpreted as being simply a consequence of the PG.

The genetics of pathological gambling

Problem and pathological gambling (PG) occurs in about 5% of Americans. Gambling is associated with substantial psychosocial and psychiatric health problems, and the increasing ease of access to gambling may increase its future prevalence. Therefore, it is important to gain greater insight into the causes of PG. Family studies of PG are consistent with a substantial familial impact on vulnerability to PG. However, family studies cannot distinguish genetic from family environmental influences. By contrast, the study of twin pairs permits the genetic and environmental influences on PG to be estimated. The study of gambling behavior among 3,359 twin pair members of the Vietnam Era Twin Registry suggests that: (1) inherited factors explain a substantial proportion of the variance in the report of symptoms of gambling; (2) there is a single continuum of genetic vulnerability that underlies gambling problems of varying severities; and, (3) the co-occurrence of PG with conduct disorder, antisocial personality disorder, and alcohol abuse/dependence is partially explained by genes that influence both PG and these other psychiatric disorders. Neurophysiological correlates of gambling problems and genetically based differences in neurotransmitter systems may provide biological mechanisms that explain the genetic basis for a predisposition to PG.

A twin study of the association between pathological gambling and antisocial personality disorder

Many individuals with a history of pathological gambling (PG) also have a history of engaging in antisocial behaviors, and this has often been interpreted as a result of the former causing the latter. In a sample of 7,869 men in 4,497 twin pairs from the Vietnam Era Twin Registry, the authors examined (a) the association between PG and antisocial personality disorder (ASPD), (b) the extent to which PG might be differentially associated with childhood conduct disorder (CD) and adult antisocial behavior (AAB), and (c) the contribution of genetic and environmental factors to the association of PG with ASPD, CD, and AAB. PG was significantly associated with all 3 antisocial behavior disorders, and the association of PG with ASPD, CD, and AAB was predominantly explained by genetic factors. The results of this study suggest that the greater-than-chance co-occurrence of PG and antisocial behavior disorders is partially due to their sharing a common genetic vulnerability. The antisocial behavior observed among many individuals with PG probably cannot be interpreted as being simply a consequence of the PG.

Genetic and environmental influences on posttraumatic stress disorder, alcohol and drug dependence in twin pairs

We investigated whether and to what degree genetic and environmental contributions overlap among posttraumatic stress disorder (PTSD), alcohol dependence (AD) and drug dependence (DD). Subjects were 3304 monozygotic and dizygotic male-male twin pair members of the Vietnam Era Twin Registry who participated in 1992 telephone administration of the Diagnostic Interview Schedule Version 3 Revised (DIS-3R). Genetic model fitting was performed to estimate the magnitude of genetic and environmental contributions to the lifetime co-occurrence of DSM-III-R PTSD, AD and DD. The liability for PTSD was partially due to a 15.3% genetic contribution common to AD and DD and 20.0% genetic contribution specific to PTSD. Risk for AD was partially due to a 55.7% genetic contribution common to PTSD and DD. Genetic influences common to PTSD and AD accounted for 25.2% of the total risk for DD. Specific family environmental influence accounted for 33.9% of the total variance in risk for DD. Remaining variance for all three disorders was due to unique environmental factors both common and specific to each phenotype. These results suggest that PTSD, AD and DD each have etiologically distinct components and also have significant genetic and unique environmental contributions in common.

Heritability of self-reported health

OBJECTIVE

To explore the contribution of genes and environmental factors to variation in a common measure (i.e., a five-point--excellent, very good, good, fair, and poor--Likert scale) of self-reported health.

DATA SOURCES

Data were analyzed from 4,638 male-male twin pair members of the Vietnam Era Twin (VET) Registry who responded to a 1987 health survey.

STUDY DESIGN

Varying models for the relationship between genetic and environmental influences on self-reported health were tested in an attempt to explain the relative contributions of additive genetic, shared and nonshared environmental effects, and health conditions reported since 1975 to perceived health status.

DATA COLLECTION

A mail and telephone survey of health was administered in 1987 to VET Registry twins.

PRINCIPAL FINDINGS

Variance component estimates under the best-fitting model included a 39.6 percent genetic contribution to self-reported health. In a model which included the effect of health condition, genes accounted for 32.5 percent and health condition accounted for 15.0 percent of the variance in self-reported health. The magnitude of the genetic contribution to perceived health status was not significantly different in a model with or without health condition.

CONCLUSIONS

These data suggest over one-third of the variability of self-reported health can be attributed to genes. Since perceived health status is a major predictor of morbidity, mortality, and health services utilization, future analyses should consider the role of heritable influences on traditional health services variables.

Self-Reported zygosity and the equal-environments assumption for psychiatric disorders in the Vietnam Era Twin Registry

The equal-environments assumption (EEA) in twin studies of psychiatric disorders assumes that the family environment which contributes to risk for a disorder is equally correlated between monozygotic (MZ) and dizygotic (DZ) twin pairs. In a study of psychiatric disorders in female twins, Kendler and colleagues (1993) have demonstrated the utility of a test of the EEA which includes a specified family environmental factor defined by using measures of perceived zygosity. We tested the EEA assumption among 3155 male-male twin pair members of the Vietnam Era Twin Registry for the following DSM-III-R lifetime disorders: alcohol dependence, marijuana dependence, any illicit drug dependence, nicotine dependence, major depression, and posttraumatic stress disorder. The majority of MZ (81.6%; n = 1593) and DZ (90.2%; n = 1086) twin pairs agreed with the investigator's assigned zygosity. The best-fitting model for each of these disorders did not allow for a specified family environmental influence. These results support the usefulness of perceived zygosity in tests of the EEA. In male twin pairs, perceived zygosity has little impact on twin similarity for common psychiatric disorders.

Testing the utility of mod scores and sib-pair analysis to detect presence of disease susceptibility loci

Linkage analyses and association studies were employed to detect disease susceptibility loci leading to elevated Q1 levels in Problem 2B. Phenotypes were defined to be the dichotomous affection status, the quantitative value for Q1, and Q1 adjusted for covariates. The method of mod-scores (for the dichotomous phenotype) and the Haseman-Elston sib-pair test on the dichotomous and quantitative phenotypes were used to screen for linkage of disease susceptibility genes to 367 markers. These analyses were performed on a sample ascertained from the first 60 replicates. The mod-score method detected linkage to MG1, MG2, and MG3 with scores of 1.5, 5.0, and 1.6 respectively. Sib-pair analysis using quantitative phenotypes signaled linkage only to the area surrounding MG1; the dichotomous phenotype detected linkage only to MG2. Association studies used ANOVA on all founders in the first 60 replicates and ASSOC on the ascertained families and on a subset of families from the 60 replicates but only confirmed an association to MG1. In conclusion, the mod-score method may be a useful tool for genomic screens.

Evidence for genetic influences common and specific to symptoms of generalized anxiety and panic

BACKGROUND

Generalized anxiety disorder (GAD) and panic disorder (PD) often co-occur and have been shown to be heritable. Researchers have debated the validity of the distinction between GAD and PD. To test for distinction between disorders, we estimated the genetic and environmental contributions which were specific and common to GAD and PD in a cohort of male-male twin pairs.

METHODS

Data were obtained from a telephone interview performed in 1992 utilizing the Diagnostic Interview Schedule Version 3-Revised. Interviews were administered to 6724 male-male monozygotic and dizygotic twin pair members of the Vietnam Era Twin Registry. We defined lifetime GAD by the report of six or more DSM-III-R symptoms and lifetime PD by the report of four or more DSM-III-R symptoms.

RESULTS

The lifetime co-occurrence of GAD and PD was best explained by a model which did not include family environmental influences. The variance in risk for GAD was due to a 37.9% influence from additive genetic factors with the remainder due to unique environmental influences. The variance in risk for PD was due to a 22.6% additive genetic contribution which was common with GAD and a 21.2% non-additive genetic contribution specific to PD with the remainder of variance in risk for PD due to unique environmental influences.

LIMITATIONS

Results may be limited to middle aged males. Model fitting with full diagnostic criteria was not possible due to low prevalences.

CONCLUSIONS

Our data suggest a distinction in liability for GAD versus PD. The common genetic influence to GAD and PD may partially account for the risk of the co-occurrence of these disorders in a lifetime.

Genetic and environmental influences on transitions in drug use

Genetic and environmental factors influence drug abuse, but abuse represents the culmination of a sequence of events. Different levels of use may have different determinants and these determinants may differ across drug types. Approximately 3200 male-male twin pairs from the Vietnam Era Twin Registry were interviewed by telephone. Data were obtained regarding exposure to six categories of illicit drugs, initiation of use, continuation of use, regular usage, and diagnosis of drug abuse/dependence. Genetic, common environmental, and unique environmental influences on transitions of drug involvement, defined as movement from one level of drug use to the next, were investigated. Marijuana had the highest conditional probability for the transition from exposure to use, from use to use more than five times, and from use more than five times to regular use. The rate of transition to regular use of heroin was higher than the rate for amphetamine, cocaine, sedatives, and psychedelics. Cocaine had the highest conditional probability for the transition from regular use to abuse/dependence. Significant genetic influences were observed for a number of transitions in marijuana, amphetamine, and cocaine usage.

Interrelationship of genetic and environmental influences on conduct disorder and alcohol and marijuana dependence symptoms

Data from the Vietnam Era Twin (VET) Registry were analyzed to explore the degree to which the same genetic and environmental factors contribute to childhood conduct disorder symptoms and to alcohol and marijuana dependence symptoms. Data on conduct disorder and alcohol and marijuana dependence were obtained from administration of the Diagnostic Interview Schedule to 1,856 monozygotic and 1,479 dizygotic male-male twin pair members of the VET Registry. Multivariate genetic models were compared to determine the genetic and environmental influences common and or specific to all three phenotypes. A full model that allowed for common genetic and environmental influences to all three phenotypes gave a good fit to the data, but the best fitting reduced model did not allow for a genetic influence on conduct disorder symptoms. Under the best fitting reduced model, genes explained 44.7% of the variance in risk for alcohol dependence symptoms. The genetic liability for symptoms of marijuana dependence was due to a 36.3% specific contribution and a 7.6% contribution from genes common with alcohol dependence symptoms. Family environmental contributions common to all three phenotypes explained 46.7%, 11.9%, and 21.3% of variance in risk for symptoms of conduct disorder, alcohol dependence, and marijuana dependence, respectively. Common family environmental factors contribute to risk of conduct disorder symptoms and alcohol and marijuana dependence symptoms. Common genetic influences contribute to risk of symptoms of alcohol dependence and marijuana dependence. While our findings suggest genes do not contribute to co-morbid conduct disorder symptoms, comparisons with other twin studies suggest that the role of genes in risk for conduct disorder remains uncertain.

Common genetic vulnerability for nicotine and alcohol dependence in men

BACKGROUND

Nicotine and alcohol dependence often occur together. We examined data from male twin pairs to determine whether there are genetic or environmental influences common to nicotine and alcohol dependence, and, if so, to estimate the magnitude and correlation of these influences.

METHODS

Subjects were 3356 male-male twin-pair members of the Vietnam Era Twin Registry who participated in a 1992 telephone administration of the Diagnostic Interview Schedule Version 3 Revised. Genetic model fitting was performed to estimate the magnitude and correlation of genetic and environmental contributions to lifetime nicotine and alcohol dependence.

RESULTS

The heritability of nicotine dependence was 60.3% (95% confidence interval [CI], 55.4%-65.2%); that of alcohol dependence, 55.1% (95% CI, 49.7%-60.5%). The best-fitting model for the co-occurrence of lifetime nicotine and alcohol dependence included a substantial genetic correlation between both disorders (r = 0.68; 95% CI, 0.61-0.74) and a modest unique environmental correlation (r = 0.23; 95% CI, 0.14-0.32).

CONCLUSIONS

These data suggest a common genetic vulnerability to nicotine and alcohol dependence in men. This common genetic influence may partially explain the clinical and epidemiological observations that alcoholics are often dependent smokers.

GABAergic cells and signals in CNS development

GABA is formed primarily from decarboxylation of glutamate by a family of cytosolic and membrane-bound GAD enzymes. In the adult, GAD-derived GABA sustains the vitality of the central nervous system (CNS), since blockage of GAD rapidly leads to convulsions and death. In plants, cytosolic GAD synthesizes GABA in response to hormones and environmental stress. Since decarboxylation involves protonation, secretion of GABA serves to buffer cytosolic pH in plant cells. Families of GAD and GABAA receptor/Cl- channel transcripts and encoded proteins emerge early and seemingly everywhere during CNS development, with their abundance closely paralleling neurogenesis and peaking before birth. Micromolar GABA acts at receptor/Cl-channels to depolarize progenitor cells in the cortical neuroepithelium; it also elevates their cytosolic Ca2+ (Cac2+) levels. In some way, these effects decrease proliferation. GABA directs the migration of postmitotic neuroblasts at femtomolar concentrations and stimulates their random motility at micromolar concentrations via Ca2+ signaling mechanisms. Activation of GABAA receptors by micromolar GABA may limit motility via membrane depolarization and elevated Cac2+. These results indicate that in vitro GABA can affect embryogenesis of the CNS through effects on cell proliferation and migration. As neurons differentiate postnatally, Cl(-)-dependent depolarization disappears together with GABAergic Cac2+ signals. Physiologically occurring GABAergic signals at Cl-channels exist in tonic and transient forms. Since the former are found on progenitor cells while both are present in postmitotic neurons, mechanisms to generate transients differentiate in the latter. Surprisingly, tonic and transient forms of GABAergic signaling at Cl-channels are rapidly and smoothly interconvertible and seem to be derived from online GABA synthesis in a surface-accessible compartment of the membrane.

Phase-compensation experiment with a 37-element adaptive optics system

An experimental study on phase compensation for turbulent effects with a 37-element adaptive optics system is performed in both a simulated turbulence cell and in a real atmosphere. The experimental results demonstrate that the compensated Strehl ratio S(0), which is influenced mainly by the deformable-mirror fitting error, has a functional form S(0) = exp[-kappa(d/r(0))(5/3)], where r(0) is Fried's coherence length and d is the average interval of the actuators on the deformable mirror. The fitting parameter kappa is 0.45. Numerical simulations are also performed with the experimental parameters. The numerical results are in agreement with data obtained in the experiment, which shows that the direct-tilt phase-reconstruction method used in our four-dimensional simulation code is reasonable.

[Comparison between the effects of rhCNTF on sensory and motor neuron of chicken embryo]

The effects of rhCNTF on dorsal root ganglia (DRG) sensory neurons and spinal cord (SC) motor neurons of 10-day chicken embryos were observed with serum-free culture. The results indicated that rhCNTF supported the survival and differentiation of these neurons and showed certain dose-dependent manners. No effect was found at 0.5 ng/ml rhCNTF concentration, a little survival promotive effect at 1.0-1.5 ng/ml, peak effect at 4 ng/ml and no more effects from 8.0 to 100 ng/ml. The survival number of neurons on 7th day was compared, and results showed higher sensitivity of sensory neuron to CNTF shortage than that of motoneuron. This suggests that survival effect of CNTF on motoneuron is only small part of its neurotrophic effects.

[The method to remove nitrite from tap water by tea]

Drinking water (tap water) is polluted in pipelines by bacteria after long distance transportation. The water contains nitrite (NO2-) which is potentially harmful to human health. The nitrite concentrations range from 0.10 to 2.0 mg/L. Our experiment proved that NO2- could not be removed by boiling, but could be removed by tea. As a natural antioxidant, tea contains several antioxidants, such as ascorbic acid and catechins, which removed NO2- from tap water effectively.

Vasoactive intestinal peptide: mediator of laminin synthesis in cultured Schwann cells

To learn more about neuropeptide-induced glial responses which accompany axon regeneration, we studied effects of VIP on laminin production by cultured Schwann cells. Schwann cells were isolated from sciatic nerves of neonatal mice, purified, and incubated for 5 days in either control medium (DMEM + 15% FCS) or control medium containing 10-7 -10-11 M VIP. At 10-7 and 10-8 M VIP, laminin levels measured by enzyme-linked immunosorbent assay were significantly higher (55% and 35%) than those in control cultures. Lower VIP concentrations (10-9 -10-11 M) produced smaller increases which were not significant. Low-affinity VIP receptors which mediated this effect were demonstrated on Schwann cells by radioligand binding studies. The increased Schwann cell synthesis of laminin induced by VIP was blocked when either a VIP antagonist or a VIP receptor antagonist was added to the VIP-containing incubation medium. In contrast to astrocytes, when Schwann cells were loaded with fura-2, VIP did not increase cytosolic Ca2+. This indicates that Schwann cells and astrocytes may have different intracellular transduction pathways; their receptor subtypes also may differ. We suggest that the VIP-induced increase in laminin synthesis which we have observed in cultured Schwann cells may also occur in vivo and might be an important component of axon-Schwann cell interactions during nerve regeneration.

The muscarinic receptor agonist oxotremorine methiodide evokes a nicotinic response in mammalian sympathetic neurons

Oxotremorine methiodide, a congener of oxotremorine, is used as a muscarinic receptor agonist. Responses to oxotremorine methiodide and nicotinic receptor agonists were examined in cultured guinea-pig celiac ganglion neurons using whole-cell voltage clamp techniques. At holding potentials between -30 and -60 mV, a brief application of oxotremorine methiodide produced fast and slow inward current transients, depending upon the concentration applied. Slowly developing inward current transients, characteristic of muscarinic responses, were produced by lower concentrations (EC50: 0.3 microM) and were blocked by atropine. Rapid inward current transients, characteristic of nicotinic responses, were produced by higher concentrations of oxotremorine methiodide (EC50: 168 microM) and were blocked by d-tubocurarine. Thus oxotremorine methiodide, at concentrations of 10 microM and greater, produced an initial nicotinic fast inward current transient followed by a slow muscarinic inward transient. The fast inward transients were similar to responses evoked by the nicotinic receptor agonists acetylcholine, nicotine and 1,1-dimethyl-4-phenyl-piperazinium iodide and were not antagonized by atropine. We conclude that oxotremorine methiodide acts as a nicotinic and muscarinic receptor agonist in celiac sympathetic ganglion neurons.