A submicron forest-like silicon surface promotes bone regeneration by regulating macrophage polarization

Introduction: Silicon is a major trace element in humans and a prospective supporting biomaterial to bone regeneration. Submicron silicon pillars, as a representative surface topography of silicon-based biomaterials, can regulate macrophage and osteoblastic cell responses. However, the design of submicron silicon pillars for promoting bone regeneration still needs to be optimized. In this study, we proposed a submicron forest-like (Fore) silicon surface (Fore) based on photoetching. The smooth (Smo) silicon surface and photoetched regular (Regu) silicon pillar surface were used for comparison in the bone regeneration evaluation. Methods: Surface parameters were investigated using a field emission scanning electron microscope, atomic force microscope, and contact angle instrument. The regulatory effect of macrophage polarization and succedent osteogenesis was studied using Raw264.7, MC3T3-E1, and rBMSCs. Finally, a mouse calvarial defect model was used for evaluating the promoting effect of bone regeneration on the three surfaces. Results: The results showed that the Fore surface can increase the expression of M2-polarized markers (CD163 and CD206) and decrease the expression of inflammatory cytokines, including interleukin-6 (IL-6) and tumor necrosis factor alpha (TNF-α). Fore surface can promote the osteogenesis in MC3T3-E1 cells and osteoblastic differentiation of rBMSCs. Furthermore, the volume fraction of new bone and the thickness of trabeculae on the Fore surface were significantly increased, and the expression of RANKL was downregulated. In summary, the upregulation of macrophage M2 polarization on the Fore surface contributed to enhanced osteogenesis in vitro and accelerated bone regeneration in vivo. Discussion: This study strengthens our understanding of the topographic design for developing future silicon-based biomaterials.

Nanoscaled Titanium Oxide Layer Provokes Quick Osseointegration on 3D-Printed Dental Implants: A Domino Effect Induced by Hydrophilic Surface

Three-dimensional printing is a revolutionary strategy to fabricate dental implants. Especially, 3D-printed dental implants modified with nanoscaled titanium oxide layer (H-SLM) have impressively shown quick osseointegration, but the accurate mechanism remains elusive. Herein, we unmask a domino effect that the hydrophilic surface of the H-SLM facilitates blood wetting, enhances the blood shear rate, promotes blood clotting, and changes clot features for quick osseointegration. Combining computational fluid dynamic simulation and biological verification, we find a blood shear rate during blood wetting of the hydrophilic H-SLM 1.2-fold higher than that of the raw 3D-printed implant, which activates blood clot formation. Blood clots formed on the hydrophilic H-SLM demonstrate anti-inflammatory and pro-osteogenesis effects, leading to a 1.5-fold higher bone-to-implant contact and a 1.8-fold higher mechanical anchorage at the early stage of osseointegration. This mechanism deepens current knowledge between osseointegration speed and implant surface characteristics, which is instructive in surface nanoscaled modification of multiple 3D-printed intrabony implants.

[Anatomical elucidation and histological study of pelvic autonomic nerve-plane based female fresh cadaver]

Objective: To investigate the rationality of nerve-plane sparing radical hysterectomy (NPSRH) for cervical cancer by observing the anatomical and histological characteristics of pelvic autonomic plane based on fresh cadaver. Methods: From October 2015 to September 2020, 14 fresh female cadavers were anatomically and histologically studied in the Laboratory of Anatomy and Embryology Department, Peking Union Medical College, Chinese Academy of Medical Sciences. The median age of the specimens was 79 years (range: 67 to 92 years). Twenty-eight hemi-pelvic specimens were obtained from 14 fresh female cadavers. NPSRH procedures were simulated in 8 hemi-pelvic cavities to prove its feasibility. Detailed dissection was conducted to recognize nerve plane and to observe the distribution of pelvic nerves in 10 hemipelvis. In the other 10 hemipelvis, whole parametrium tissue was taken from the crossing of ureter and the uterine artery to the ureterovesical entrance and be embedded, then continuous section was performed, and was stained by hematoxylin-eosin staining (HE) to observe the relationship of nerves and vessels. Immunohistochemical staining of S100, tyrosine dehydrogenase (TH), and vasoactive intestinal peptide (VIP) were performed to count and distinguish sympathetic and parasympathetic nerves, respectively. Results: (1) The pelvic autonomic nerve-plane was completely preserved in 7 of 8 hemipelvis by simulating NPSRH. (2) After detailed dissection in 10 hemipelvis, it was found that hypogastric nerve, pelvic splanchnic nerve, and their confluence of inferior hypogastric plexus were distributed in a planar statelocating in the ureteral mesentery and its caudal extension. This nerve plane showed a cross relationship with deep uterine vein and its branches. The bladder branches and vesical venous plexus were closely related to the inferior hypogastric plexus. The middle vesical vein and inferior vesical vein were intact in 7 of 10 hemipelvis, and either vesical vein was missing in 3 of them. It was observed that the vesical venous plexus communicated with the deep uterine vein trunk on the medial side of the nerve plane in 6 hemipelvis, while flowed into the deep uterine vein on the lateral side of the nerve plane in 2 hemipelvis, and in the other 2 hemipelvis it directly flowed into the internal iliac vein. (3) It was revealed that autonomic nerves were continuously distributed beneath the ureteral with sagittal plane by HE staining. The average nerve content below the ureteral width was 70.9% of the total in nerve plane by S100 staining. TH and VIP staining showed that the average number of sympathetic fibers was 13.5 and parasympathetic fibers was 8.2, reminding sympathetic predominated. Conclusion: Pelvic autonomic nerves are mainly distributed within the mesangial plane below the ureter, which provides an anatomic justification for NPSRH.

The Osteoinductivity of Calcium Phosphate-Based Biomaterials: A Tight Interaction With Bone Healing

Calcium phosphate (CaP)-based bioceramics are the most widely used synthetic biomaterials for reconstructing damaged bone. Accompanied by bone healing process, implanted materials are gradually degraded while bone ultimately returns to its original geometry and function. In this progress report, we reviewed the complex and tight relationship between the bone healing response and CaP-based biomaterials, with the emphasis on the in vivo degradation mechanisms of such material and their osteoinductive properties mediated by immune responses, osteoclastogenesis and osteoblasts. A deep understanding of the interaction between biological healing process and biomaterials will optimize the design of CaP-based biomaterials, and further translate into effective strategies for biomaterials customization.

Enhanced Osseointegration by the Hierarchical Micro-Nano Topography on Selective Laser Melting Ti-6Al-4V Dental Implants

Currently, selective laser melting (SLM) has been thriving in implant dentistry for on-demand fabricating dental implants. Based on the coarse microtopography of SLM titanium surfaces, constructing nanostructure to form the hierarchical micro-nano topography is effective in enhancing osseointegration. Given that current nanomodification techniques of SLM implants, such as anodization and hydrothermal treatment, are facing the inadequacy in costly specific apparatus and reagents, there has been no recognized nanomodified SLM dental implants. The present study aimed to construct hierarchical micro-nano topography on self-made SLM dental implants by a simple and safe inorganic chemical oxidation, and to evaluate its contribution on osteoblastic cells bioactivity and osseointegration. The surface chemical and physical parameters were characterized by FE-SEM, EDS, profilometer, AFM, and contact angle meter. The alteration on bioactivity of MG-63 human osteoblastic cells were detected by qRT-PCR. Then the osseointegration was assessed by implanting implants on the femur condyle of New Zealand Rabbits. The hierarchical micro-nano topography was constituted by the microrough surface of SLM implants and nanoneedles (diameter: 20∼50 nm, height: 150∼250 nm), after nanomodifying SLM implants in 30% hydrogen peroxide and 30% hydrochloride acid (volume ratio 1:2.5) at room temperature for 36 h. Low chemical impurities content and high hydrophilicity were observed in the nanomodified group. Cell experiments on the nanomodified group showed higher expression of mitophagy related gene (PINK1, PARKIN, LC3B, and LAMP1) at 5 days and higher expression of osteogenesis related gene (Runx2 and OCN) at 14 days. In the early stage of bone formation, the nanomodified SLM implants demonstrated higher bone-to-implant contact. Intriguingly, the initial bone-to-implant contact of nanomodified SLM implants consisted of more mineralized bone with less immature osteoid. After the cessation of bone formation, the bone-to-implant contact of nanomodified SLM implants was equal to untreated SLM implants and marketable TixOs implants. The overall findings indicated that the inorganic chemical oxidized hierarchical micro-nano topography could enhance the bioactivity of osteoblastic cells, and consequently promote the peri-implant bone formation and mineralization of SLM dental implants. This study sheds some light on improvements in additive manufactured dental implants.

Magnetic resonance spectroscopy may serve as a presurgical predictor of somatostatin analog therapy response in patients with growth hormone-secreting pituitary macroadenomas

PURPOSE

Somatostatin analogs (SSAs) are considered one of the most effective medical treatments for patients with growth hormone-secreting pituitary adenomas (GH-PAs). The postoperative electron microscopy (EM) pathological subtype and SSTR2 expression in the tumor are the most established predictors of patient response to SSA therapy. The aim of this study was to evaluate how will magnetic resonance spectroscopy (MRS) measurements before surgery predict the EM pathological subtypes and SSTR2 expression of tumors, and thereby serve as an indicator for the therapeutic sensitivity to SSAs of patients with GH-PAs.

METHODS

Eighteen patients with GH pituitary macroadenomas who underwent transsphenoidal surgery were included in this retrospective study. The preoperative MRS data and T2 signal intensity were obtained from patients by 1.5 T MR spectroscopy of the sellar mass. The EM pathological subtypes of tumors were determined after surgery through examination of cell granulations. The expressions of somatostatin receptor 2 (SSTR2), SSTR5, P21, P27, and Ki-67 were evaluated by immunohistochemistry.

RESULTS

The MRS parameters that were found to significantly predict the EM pathological subtypes of tumors, as calculated by the receiver operating characteristic curve, were the choline (Ch) value at 3140.5 MR units (sensitivity 69.2%, specificity 100%) and the choline/creatine (Ch/Cr) ratio at 1.27 (sensitivity 92.3%, specificity 100%). Further, the Ch/Cr ratio, but not other MRS data, was shown to negatively correlate with the expression of SSTR2 (P = 0.02). The Ch/Cr ratio was also found to positively correlate with the Ki-67 value (P < 0.05) and T2 signal (P < 0.05), but not with other factors that were examined in this study. Moreover, the Ch/Cr ratio could predict the EM pathological subtypes of tumors with an accuracy of 83.3% (5/6) for patients with an isointense T2 signal.

CONCLUSION

The Ch/Cr ratio by MRS could effectively predict the tumor subtype and was significantly correlated with the expression of SSTR2, which was consistent with other predictors. It was also able to distinguish the patients with isointense T2 signals. Our results provide a potentially new and non-invasive method to predict the response to SSAs in patients with GH pituitary macroadenomas.

[Comparative study of three-dimensional versus two-dimensional laparoscopic C1 radical hysterectomy for cervical cancer]

Objective: To compare the clinical effects and the subjective perception of surgeons with three-dimensional (3D) and two-dimensional (2D) laparoscopic C1 radical hysterectomy surgeries for cervical cancer. Methods: The retrospective cohort study was conducted. The clinicopathological data of 101 patients with cervical cancer who received C1 laparoscopic radical hysterectomy (C1-LRH) surgery from June 2015 to August 2017 were collected. Of all patients, 42 cases undergoing 3D laparoscopic surgery and 59 cases undergoing 2D laparoscopic surgery were respectively allocated into the C1-3DLRH group or C1-2DLRH group. The clinical effect and the subjective perception of surgeons were compared between the two groups. Results: (1) There was no significant difference between the C1-3DLRH group and C1-2DLRH group in terms of age, body mass index (BMI), International Federation of Gynecology and Obstetrics (FIGO) stage, pathologic type, etc. (all P>0.05). Compared with C1-2DLRH group, the operation time was significantly shortened [(192±54) vs (221±54) minutes, P<0.01], blood loss was significantly less [(102±88) vs (167±117) ml, P<0.01], and the success rate of inferior hypogastric plexus (IHP) bladder branch preservation was significantly increased [86% (36/42) vs 66% (39/59), P<0.05] in C1-3DLRH group. There were no significant difference in the number of lymph nodes, the incidence of operative complications, the infection rate, the time of catheterization and the length of hospitalization between the two groups (all P>0.05). The long-term bladder function was evaluated at the twelfth month after operation, 39 patients in the C1-3DLRH group and 53 patients in the C1-2DLRH group were completed the survey. The results showed that 13% (5/39) of the patients in the C1-3DLRH group had long-term bladder dysfunction, which was lower than that 21% (11/53) of the C1-2DLRH group, but there was no significant difference between the two groups (χ(2)=0.980, P=0.322). (2) A total of 251 laparoscopic surgeons questionnaires were eligible. The incidence of side effects in the first and second generation of 3D and 2D laparoscopic surgeons was 20.4% (10/49), 6.9% (6/87) and 3.5% (4/115), respectively. The incidence of side effects in the first generation of 3D laparoscopic surgeons was higher than that in the second generation of 3D (χ(2)=5.463, P=0.019) and 2D laparoscopic surgeons (χ(2)=12.475, P<0.01). There was no difference between the second generation of 3D and 2D laparoscopic surgeons (χ(2)=1.208, P=0.272). Conclusions: 3D laparoscopy is advantageous to the preservation of autonomic nerve in C1-LRH operation and may improve the quality of operation compared with 2D laparoscopy. The second generation of 3D laparoscopic device might overcome the side effects of the surgeons.

Study on the relationship between the RASSF10 gene and the biological behavior of hepatocellular carcinoma cells

OBJECTIVE

To investigate the relationship between Ras association domain family gene 10 (RASSF10 gene) and the biological behavior of hepatocellular carcinoma (HCC), including proliferation, invasion, and metastasis.

MATERIALS AND METHODS

HCC cell lines were generated with stable overexpression or low expression of RASSF10 protein. A cell line transfected with an empty vector was treated as control. At 12, 24, 48, and 72 h, the cell proliferation was determined by MTT assay, the invasion ability was determined by Transwell chambers, and the scratch assay was used to assess the migration ability. Additionally, cell lines were injected subcutaneously in the axillary fossa of nude mice aged 5-6 weeks. Tumors were measured weekly for 6 consecutive weeks to observe tumor volume, tumor growth rate, weight, and tumor metastasis in nude mice of the different groups.

RESULTS

In both the control group and low expression group, cell proliferation rates, cell invasion, and migration abilities, increased over time but decreased over time in the overexpression group. At each time point, data in the overexpression group were markedly lower than those in the control group, and highest in the low expression group. The differences were statistically significant (p<0.05). In both control group and low expression group, tumor volume, tumor growth rate, weight, and tumor metastasis number were increased in nude mice over time, while they decreased in the overexpression group (except for tumor metastasis number). At each time point, data in the overexpression group were markedly lower than in the control group, and highest in the low expression group. The differences were statistically significant (p<0.05).

CONCLUSIONS

Like a tumor suppressor gene, RASSF10 can inhibit the proliferation, invasion, and migration of HCC cells.

Childhood obesity patterns and relation to middle-age sleep apnoea risk: the Bogalusa Heart Study

BACKGROUND

Obese adults have a higher risk of obstructive sleep apnoea (OSA); however, the relationship between childhood obesity and adult OSA risk is unclear. Objectives This study aimed to examine overweight/obesity (OW) in childhood and risk of OSA in middle age.

METHODS

Childhood OW status was classified as never OW, weight cycling, persistent OW and incident OW. After 35 years of follow-up, high risk for OSA was determined by a positive score in ≥2 domains on the Berlin Questionnaire with obesity removed from scoring.

RESULTS

At initial assessment, mean (SD) age was 9.9 (2.9) years, and 23.9% were OW. Overall, 25.7% had scores indicating a high risk for OSA. Compared with participants who were never OW, those with persistent OW and incident OW were 1.36 (95%CI: 1.04-1.77) and 1.47 (1.11-1.96) times more likely to be high risk for OSA, after adjustment for multiple risk factors and adult OW status. Participants with an OW duration of 1-4 years, 5-8 years, and 8+ years were 0.96 (0.44-2.09), 1.20 (0.70-2.04) and 1.52 (1.22-1.90) times more likely to be high risk for OSA compared with those who were never OW (P for trend: 0.0002).

CONCLUSIONS

These results suggest that childhood OW is associated with a high risk of OSA in middle age.

Functional characterization of Bombyx mori nucleopolyhedrovirus mutant lacking late expression factor 9

Baculoviridae is a family of invertebrate viruses with large double-stranded DNA genomes. Proteins encoded by some late expression factor (lef ) genes are involved in the regulation of viral gene expression. Lef-9 is one of four transcription-specific Lefs, which are components of the virus-encoded RNA polymerase, and can initiate and transcribe late and very late genes. As a multifunctional protein encoded by the Bombyx mori nucleopolyhedrovirus (BmNPV), Lef-9 may be involved in the regulation of viral propagation. However, the underlying mechanism remains unclear. To determine the role of lef-9 in baculovirus infection, lef-9-knockout virus (lef-9-KO-Bacmid virus) was constructed using the Red recombination system, and the Bac-to-Bac system was used to prepare lef-9-repaired virus (lef-9-Re-Bacmid virus). The lef-9-KO virus did not produce infectious viruses or show infection activity, while the lef-9-repaired virus recovered both. Quantitative real-time polymerase chain reaction (qRT-PCR) analysis of the transcription levels in wild-type-Bacmid, lef-9-KO-Bacmid, and lef-9-Re-Bacmid viruses showed that the lef-9-KO bacmid had little effect on viral genome replication. However, the transcription levels of the early and late viral genes, lef-3, ie-1, vp39, and p10, were significantly lower in BmN cells transfected with lef-9-KO-Bacmids than in the controls. Electron microscopy showed no visible enveloped virions in cells transfected with lef-9-KO-Bacmids, while many mature virions in cells transfected with lef-9-Re-Bacmid and wt-Bacmid were present. Thus, lef-9 was not essential for viral genome replication, but significantly affected viral gene transcription and expression in all periods of cell life cycle.

Design of pulsed guiding magnetic field for high power microwave generators

In this paper, we present a comprehensive study on designing solenoid together with the corresponding power supply system to excite pulsed magnetic field required for high power microwave generators. Particularly, a solenoid is designed and the excited magnetic field is applied to a Ku-band overmoded Cerenkov generator. It is found in experiment that the electron beam is properly guided by the magnetic field and a 1.1 GW high power microwave is achieved at a central frequency of 13.76 GHz. Pulsed solenoid system has the advantages of compactness and low energy consumption, which are of great interest for repetitive operation. The reported studies and results can be generalized to other applications which require magnetic fields.

The treatment effect of the atopic dermatitis by electrolytic-reduction ion water lotion

A female in her late 20s was diagnosed with systemic atopic dermatitis in another hospital 5 years earlier and treated by steroid ointment application to the affected areas and oral steroid administration. She visited our hospital due to the aggravation of dermatitis symptoms over the entire face from 1 week earlier. Lesions were present on the face, chest, neck, and bilateral upper limbs, and, in particular, facial dermatitis was extensive. A diagnosis of systemic atopic dermatitis complicated by infection was made. As oral drugs, a herbal medicine and steroid/antihistamine combination tablet were used. As topical drugs, an steroid/antibiotic combination ointment and vitamin E/A ointment were applied. In addition, injections for the treatment of allergic disease were used, and acidic electrolyzed water and an electrolyticreduction ion water (ERI) lotion were topically applied. While receiving the two types of oral drug, she received a subcutaneous injection once a week and the application of acidic electrolyzed water, ERI lotion, steroid/antibiotic combination ointment, and vitamin E/A ointment to the lesions twice a day. One week after the initiation of treatment, redness and swelling decreased. After 1 month, the swelling further decreased, but the redness remained. After 1.5 months, the redness further decreased, showing a favorable course. Three months after the initiation of treatment, slight redness remained, but the skin color was almost normal. This patient showed the improvement of skin redness and swelling and an almost normal skin state without pigmented scars. These results suggest the effectiveness of complex therapy consisting of a herbal medicine and steroid/antihistamine combination drug as oral drugs and an steroid/antibiotic combination ointment and vitamin E/A ointment as topical drugs, injections for allergic disease, and acidic electrolyzed water and ERI lotion for disinfection and skin care.

Trial of chemotherapy (CHT) plus hormonal therapy an initial treatment for prostate cancer (PC)

14637

Background: The delivery of CHT in a setting of androgen-independent (AI) PC has demonstrated: survival benefit associated with a PSA decline and tolerable toxicity, thus strongly suggesting that disease modifying potential exists. Preclinical data supports the benefit of simultaneous CHT and androgen deprivation (AD). The stage is set for CHT to be given earlier in men with PC. Data suggests a transformation from an androgen-dependent to an AI phenotype is mediated by the expansion of an AI clone already present at the time of AD. If this model is correct, it would be feasible to bring CHT up front when the corresponding tumor burden is minimal. Methods: A course of CHT is defined as 8 weeks (6 on/2 off). The therapy consists of weeks 1, 3, and 5 with adriamycin 20 mg/m2 as a 24 hour intravenous infusion on the first day of every week in combination with ketoconazole 400 mg orally 3 times a day, daily for 7 days. Weeks 2, 4, and 6 treatment consisted of docetaxel 35 mg/m2 intravenously over 1 hour on the first day of every week in combination with estramustine 280 mg orally 3 times a day, daily for 7 days. Hormone therapy, GnRH antagonist, is initiated within the first 6 months of starting CHT. Following the completion of 3 courses of CHT, the addition of casodex occurs. Hormone management then continues for a total of 24 months, and then is discontinued. Patients (pts) are followed every 12 weeks with a PSA, testosterone and routine laboratory evaluation. For those men who have had a PSA recurrence, hormone therapy will be reinitiated. Results: 34 men have been enrolled to date. 47% of the men had no prior local therapy, while the other 35% had surgery, 15% had radiation therapy or 3% had both. 3% had a gleason 6, 41%/7, 26%/8, 27%/9 and 3%/10. 64% of the men presented with bone and/or nodal metastasis. Baseline median PSA was 11.2 (1.0–1065.5). The median PSA reduction to date has been 96% with associated nodal and bone scan improvement. Conclusion: Information regarding PSA response, radiographic outcome, toxicity and results of men who are discontinuing hormones will be presented.

[Table: see text]

A defective nontransmissible recombinant Sendai virus mediates efficient gene transfer to airway epithelium in vivo

Recombinant Sendai virus (SeV)-mediated gene transfer to differentiated airway epithelial cells has shown to be very efficient, because of its ability to overcome the intra- and extracellular barriers known to limit gene delivery. However, this virus is transmission competent and therefore unlikely to be suitable for use in clinical trials. A nontransmissible, replication-competent recombinant SeV has recently been developed by deleting the envelope Fusion (F) protein gene (SeV/DeltaF). Here we show that SeV/DeltaF is able to mediate beta-galactosidase reporter gene transfer to the respiratory tract of mice in vivo, as well as to human nasal epithelial cells in vitro. Further, in an ex vivo model of differentiated airway epithelium, SeV/DeltaF gene transfer was not importantly inhibited by native mucus. When compared to the transmission-competent SeV in vivo, no difference in gene expression was observed at the time of peak expression. The development of an F-defective nontransmissible SeV, which can still efficiently mediate gene transfer to the airway epithelium, represents the first important step towards the use of a cytoplasmic RNA viral vector in clinical trials of gene therapy.

Renal and peri-renal abscesses in children: proposed physio-pathologic mechanisms and treatment algorithm

Renal and perinephric abscess in children are uncommon. Three basic pathophysiologic mechanisms are involved, namely, hematogenous spread, ascending infection and contamination by proximity to an infected area. Six pediatric patients diagnosed with renal abscess were treated at our institution from 1990-2000. Five patients were females; ages ranged from 3-17 years (mean 11.8 years). Diagnosis, as expected, was not readily apparent at presentation. Computerized tomography and renal sonograms were the most useful imaging modalities. Gram-negative bacteria were commonly isolated; only one patient grew Staphylococcus aureus. All patients received broad-spectrum intravenous antibiotics. Additional treatments consisted of percutaneous drainage (4 patients), exploratory laparotomy (1 patient, for presumed Wilm's tumor) and nephrectomy (2 patients). A new classification of the etiologic mechanisms of this condition is proposed along with a simple and practical treatment algorithm.

Development of the perforating pathway: an ipsilaterally projecting pathway between the medial septum/diagonal band of Broca and the cingulate cortex that intersects the corpus callosum

The perforating pathway (PFP) intersects the corpus callosum perpendicularly at the midline in the dorsoventral axis. Therefore axons in either the PFP or the corpus callosum make different axonal guidance decisions in the same anatomical region of the developing cortical midline. The mechanisms underlying these axonal choices are not known. To begin to identify these guidance mechanisms, we characterized the development of these two pathways in detail. The development of the corpus callosum and its pioneering projections has been described elsewhere (Shu and Richards [2001] J. Neurosci. 21:2749--2758; Rash and Richards [2001] J. Comp. Neurol. 434:147--157). Here we examine the development, origins, and projections of axons that make up the PFP. The majority of axons within the PFP originate from neurons in the medial septum and diagonal band of Broca complex. These neurons project in a topographic manner to the cingulate cortex. In contrast to previous reports, we find that a much smaller projection originating from the cingulate cortex also contributes to this pathway. The pioneering projections of the PFP and the corpus callosum arrive at the corticoseptal boundary at around the same developmental stage. These findings show that ipsilaterally projecting PFP axons and contralaterally projecting callosal axons make distinct guidance decisions at the same developmental stage when they reach the corticoseptal boundary.

Acute renal failure due to rhabdomyolysis associated with radical perineal prostatectomy

We report a case of acute renal failure due rhabdomyolysis as a result of the exaggerated lithotomy position during radical perineal prostatectomy. The pathogenesis, diagnosis, management, and preventive measures of acute renal failure associated with rhabdomyolysis are also reviewed.

Cortical axon guidance by the glial wedge during the development of the corpus callosum

Growing axons are often guided to their final destination by intermediate targets. In the developing spinal cord and optic nerve, specialized cells at the embryonic midline act as intermediate targets for guiding commissural axons. Here we investigate whether similar intermediate targets may play a role in guiding cortical axons in the developing brain. During the development of the corpus callosum, cortical axons from one cerebral hemisphere cross the midline to reach their targets in the opposite cortical hemisphere. We have identified two early differentiating populations of midline glial cells that may act as intermediate guideposts for callosal axons. The first differentiates directly below the corpus callosum forming a wedge shaped structure (the glial wedge) and the second differentiates directly above the corpus callosum within the indusium griseum. Axons of the corpus callosum avoid both of these populations in vivo. This finding is recapitulated in vitro in three-dimensional collagen gels. In addition, experimental manipulations in organotypic slices show that callosal axons require the presence and correct orientation of these populations to turn toward the midline. We have also identified one possible candidate for this activity because both glial populations express the chemorepellent molecule slit-2, and cortical axons express the slit-2 receptors robo-1 and robo-2. Furthermore, slit-2 repels-suppresses cortical axon growth in three-dimensional collagen gel cocultures.

The spatial and temporal expression patterns of netrin receptors, DCC and neogenin, in the developing mouse retina

Recently it has been demonstrated that the guidance of retinal ganglion cell (rgc) axons through the optic disc is dependent on the DCC/netrin-1 axonal guidance system. To gain further insight into the function of the netrin receptors, DCC and Neogenin, in retinal development we have studied the expression patterns of these receptors in the embryonic mouse retina. Neogenin mRNA was restricted to a single neural cell type, the rgc. However, strong Neogenin mRNA expression was observed in the extending fiber cells of the developing lens suggesting a role for Neogenin in the migration events shaping the early lens. Our studies demonstrated that DCC mRNA was expressed at high levels in chains of closely opposed neurons as they migrated towards the emerging mantle layer in the early retina (E12.5-E13.5) suggesting a role for DCC in the migration of neurons out of the ventricular zone. DCC protein expression was high on rgc axons as they actively navigated through the optic disc into the optic nerve. At birth, when the majority of rgc axons had projected through the optic disc, DCC protein was no longer detectable on the distal axonal segments within the optic nerve despite significant DCC protein expression on the proximal axonal membranes in the nerve fiber layer. These observations suggest that a localized down-regulation of DCC protein occurs on projecting axonal membranes once the DCC guidance function is no longer required. We also demonstrated that DCC mRNA and protein were expressed by amacrine cells and Müller glial cells while DCC mRNA was detected in horizontal cells. Taken together, these expression patterns suggest a role for DCC in axon outgrowth and/or pathfinding for a variety of retinal neurons and in the migration of newly born neurons within the developing retina.

Expression of the netrin-1 receptor, deleted in colorectal cancer (DCC), is largely confined to projecting neurons in the developing forebrain

Axon guidance mechanisms are crucial to the development of an integrated nervous system. One family of molecules that may be important in establishing axonal connectivity in mammals is the Netrins, and their putative receptors DCC (deleted in colorectal cancer), Neogenin, and Unc-5. Knockout and mutational analyses of some of these genes have shown that they are critically involved in the development of several specific pathways in the developing brain. However, previous expression analyses of these genes have largely been confined to the developing spinal cord. In the present study, we analyzed the expression of DCC in the developing mouse forebrain. We found that DCC protein is expressed in specific axonal populations projecting from the developing olfactory bulb, neocortex, hippocampus, and epithalamus/habenular complex. In the developing olfactory bulb and neocortex, DCC expression is particularly evident during the targeting phase of axon outgrowth and is then rapidly downregulated. As predicted from the knockout and mutational analyses of this gene, DCC is expressed in axonal commissures, in particular the corpus callosum, hippocampal commissure, and the anterior commissure. In addition, we found that DCC is expressed in the habenular commissure, the fasciculus retroflexus, and the stria medularis. Therefore, this analysis implicates a function for DCC in additional axonal guidance systems not predicted from the knockout and mutational analyses.

Intracellular accumulation of insoluble, newly synthesized abetan-42 in amyloid precursor protein-transfected cells that have been treated with Abeta1-42

Our early study indicates that intracellular Abeta1-42 aggregates are resistant to degradation and accumulate as an insoluble residue in lysosomes, where they alter the normal catabolism of amyloid precursor protein (APP) to cause the accumulation of insoluble APP and amyloidogenic fragments. In this study, we examined whether the addition of exogenous Abeta1-42 also leads to the accumulation of newly synthesized intracellular Abeta. Here we describe that newly synthesized Abeta, especially Abetan-42, is generated from metabolically labeled APP and accumulates in the insoluble fraction of cell lysates after Abeta1-42 treatment. These results suggest that intracellular Abeta may derive from a solid phase, intracellular pathway. In contrast to the pathway that primarily produces secreted Abeta1-40, the solid-phase intracellular pathway preferentially produces Abetan-42 with ragged amino termini. Biochemical studies and amino acid sequencing analyses indicate that these intracellular Abeta also share the same types of Abeta structures that accumulate in the brain of Alzheimer's disease patients, suggesting that a significant fraction of the amyloid deposits in Alzheimer's disease may arise by this solid-phase pathway.

Importance of coronary artery spasm in alcohol-related unexplained syncope

To examine the role of coronary artery spasm in patients with syncope after alcohol ingestion, we performed an intracoronary ergonovine provocation test in 7 male patients (39 to 73 years old, mean 54 years) with alcohol-related syncope which remained unexplained despite noninvasive cardiovascular and neurological examinations. No patients had structural heart disease or significant coronary artery stenosis. Ergonovine was continuously infused into each coronary artery at a rate of 10 micrograms/min for up to 5 min. Coronary artery spasm with ST-segment elevation was induced in 4 of 7 patients. Chest pain before syncope or history of chest pain were not present in 3 of 4 patients with a positive ergonovine test. Multivessel coronary artery spasm was induced in 3 patients. One patient presented with triple vessel coronary artery spasm progressing to near syncope as a result of profound hypotension and ventricular tachycardia during provocation. Coronary artery spasm was promptly relieved by intracoronary isosorbide dinitrate infusion. All patients with a positive ergonovine test were treated with calcium antagonist and did not experience syncope during follow-up. These results suggest that coronary artery spasm is one of the important causes of syncope after alcohol ingestion.

[Regional wall motion of the left ventricle in congestive cardiomyopathy: in comparison with progressive muscular dystrophy of Duchenne type (author's transl)]

The features of regional wall motion abnormalities of the left ventricle were analysed in 11 patients of congestive cardiomyopathy (CCM) in comparison with 22 patients of progressive muscular dystrophy (DMD) of Duchenne type who showed an abnormal motion of the left ventricle by echocardiography. Real time two-dimensional echocardiographic study demonstrated the following results: I) In CCM, (1) only 2 or less of 11 cases preserved a normal motion in each left ventricular segment, and the depression of wall motion of the left ventricle were thought to be generalized; (2) there were 9 cases with segmental wall motion abnormalities and 3 of them demonstrated ventricular aneurysms, and (3) the localizations of the segmental abnormalities varied in each case, and there was no apparent accumulation to any segments. II) In DMD, (1) all the cases showed depressed motions and 8 of them demonstrated a ventricular aneurysm in the posterior wall of the left ventricle (LVPW), (2) while, there was no case showing ventricular aneurysm in the segments other than LVPW, and about one third of all cases showed normal motion in those segments. From these results, we concluded as follows: 1) Although the depression of a wall motion of the left ventricle was generalized in CCM, this was not always uniform and the segmental abnormalities of a wall motion were frequently observed. The localization of the most severely disturbed segment varied in each case. 2) On the other hand, in DMD, the wall motion was disturbed more frequently and more severely in LVPW than in other ventricular segments.

Significance of echocardiographic evaluation on surgery to mitral stenosis

1) Diastolic descent rate (DDR) of the anterior mitral leaflet improved after the surgery. However, this improvement was not modified with a) atrial fibrillation b) damages of the subvalvular supporting tissue c) valvular calcification d) the method of the operation, namely the open or closed commissurotomy. 2) DDR was fairly well correlated with the mitral orifice area, the cardiac output and the pressure gradient across the mitral valve. Therefore, the echocardiographic diagnosis and the follow up evaluation of the mitral stenosis after the surgery were thought to be very reliable, considering the accuracy of this diagnosis as disclosed in this study. The contributory effect to DDR was discussed.