In vivo monitoring of the bone healing process around different titanium alloy implant surfaces placed into fresh extraction sockets

Objectives

Increasing surface roughness and coating with tricalcium phosphate of titanium and titanium alloy implants has been proposed to provide better rates of osseointegration. However, how these changes in surface topography and chemistry influence the osseointegration process of immediate implants placed in fresh extraction sockets is unclear. This study investigated the influence of three clinically employed implant surfaces on the early bone healing events in vivo.

Methods

Machined smooth implants were milled from grade 5 Ti6Al4V titanium. Surfaces were moderately roughened by grit blasting, which were then coated with tricalcium phosphate. Implants were placed into freshly extracted incisor sockets of mandibles of normal Wistar rats and left for 1, 3 and 9 weeks. Healing bone tissue around the implants was examined by histochemistry and immunocytochemistry to localise PCNA proliferative cells, and osteoblast differentiation markers osteopontin and osteocalcin. Positive synthesising cells were counted using image analysis.

Results

Histology indicated no differences in the amount or pattern of bone formation within the healing tissue surrounding the different implant surfaces. Bone healing occurred predominantly on exposed bone surfaces (distance osteogenesis) and not on the implant surface (contact osteogenesis). No differences were observed in the number or timing of PCNA, osteopontin and osteocalcin positive cells within the bone healing tissue around each of the implant analysed.

Conclusion

For immediately placed implants, the surface modifications investigated appeared to have little influence on the activity of bone forming cells surrounding the implant, probably due to the high level of distance osteogenesis seen within this scenario.

Clinical significance

For immediate placement of implants into fresh extraction sockets, titanium implants with roughened surfaces and coating with tricalcium phosphate have negligible influence in accelerating the early bone healing events of osseointegration.     

Effect of depression and neuropathic pain using questionnaires on quality of life in patients with low back pain; cross-sectional retrospective study

Purpose

The present study investigated the percentage of low back pain (LBP) patients who have depressive symptoms and neuropathic pain and analyzed the effects of these on the quality of life (QOL) in these patients.

Methods

Of the 650 new patients with LBP that visited the hospital between June 2012 and December 2013, 309 patients who completed questionnaires to assess LBP and QOL were included in the study. The questionnaire included demographic items, the self-rated depression scale (SDS)-Zung, the Japanese version of the PainDETECT questionnaire (PDQ-J), numerical pain rating scale (NRS), and QOL assessments. The patients were divided into two groups according to their SDS-Zung scores: a nondepressed group with SDS scores <40 and a depressed group with SDS-Zung scores ≥50.

Results

One hundred twenty-five patients (40.5 %) were classified as nondepressed and 63 (20.4 %) as depressed. The mean PDQ-J score was higher in depressed patients than in nondepressed patients. The frequency of neuropathic pain was greater in depressed patients, with neuropathic pain observed in 17 of the 63 (27 %) depressed LBP patients and 11 of the 125 (9 %) nondepressed LBP patients. The SDS-Zung and PDQ-J scores of LBP patients were correlated significantly (r = 0.261, p < 0.001). Depressed patients had higher pain NRS scores and lower QOL scores compared with nondepressed patients.

Conclusions

Both the depressed patients and those with neuropathic LBP had a higher level of pain, greater pain-related disability, and poorer QOL compared with nondepressed patients. This is the first study to use the SDS-Zung and PDQ-J screening questionnaires to estimate the presence of neuropathic pain associated with depressive symptoms in LBP patients and to evaluate the impact of these on QOL.

     

CD133 Expression at the Metastatic Site Predicts Patients’ Outcome in Colorectal Cancer with Synchronous Liver Metastasis

Background

CD133 is a transmembrane protein that is proposed to be a stem cell marker of colorectal cancer (CRC); however, the correlation between CD133 expression and survival of CRC patients with liver metastasis has not been fully examined.

Methods

CD133 expression was evaluated immunohistochemically, both in primary tumors and synchronous liver metastases of 88 consecutive CRC patients, as well as recurrent lesions in the remnant liver of 27 of these 88 patients. The relationship between CD133 expression and clinicopathological characteristics, recurrence-free survival, and overall survival (OS) was analyzed.

Results

CD133 expression in liver metastases (mCD133) was detected in 50 of 88 patients (56.8 %), and had significant correlation with CD133 expression in primary lesions (pCD133) (p < 0.001). CD133 expression in liver recurrent lesions (recCD133) also had a significant correlation with mCD133 (p < 0.001). mCD133+ patients had significantly longer disease-free survival (p = 0.043) and OS (p = 0.014) than mCD133? patients. In addition, mCD133+ patients had a significantly lower rate of extrahepatic recurrence (p < 0.001).

Conclusions

Patients without CD133 expression in liver metastasis had significantly shorter survival, perhaps because mCD133? patients had a significantly higher rate of extrahepatic recurrence.

     

Involvement of the protein kinase Cgamma isoform in development of tolerance to nitrous oxide-induced antinociception in mice

Prolonged exposure to nitrous oxide (N2O) results in development of acute tolerance to its antinociceptive effect. Cross-tolerance to N2O-induced antinociception is also observed in morphine-tolerant animals. Despite increasing evidence of tolerance development to N2O-induced antinociception, the details of the mechanisms that underlie this tolerance remain unknown. The present study was conducted to investigate the involvement of brain protein kinase C (PKC) isoform in these two types of tolerance to N2O-induced antinociception in mice. Prolonged exposure (41 min in total, including 30 min pre-exposure and 11 min of antinociceptive testing) to 70% N2O produced a reduction in N2O-induced antinociception, indicating development of acute tolerance. The prolonged exposure to 70% N2O caused an activation of PKCgamma isoform in the brain, but not the PKCepsilon isoform. Pretreatment with a PKCgamma-antisense oligonucleotide but not the corresponding mismatch oligonucleotide (i.c.v.) prevented the development of acute tolerance to N2O-induced antinociception. Chronic morphine treatment (10 mg/kg, s.c., b.i.d. for 5 days) resulted in development of tolerance to morphine-induced antinociception and cross-tolerance to N2O-induced antinociception. The development of tolerance to morphine and cross-tolerance to N2O were both inhibited by pretreatment with PKC inhibitor, chelerythrine (1 nmol, i.c.v.). Morphine-tolerant mice showed an activation of PKC within the brain, which was suppressed by pretreatment with chelerythrine (1 nmol, i.c.v.). Thus, activation of brain PKC, in particular, the PKCgamma isoform, appears to play an important role in the development of both acute tolerance and cross-tolerance to N2O-induced antinociception in mice.     

Predictive Ability of the Five-time Chair Stand Test for Postoperative Pneumonia after Minimally Invasive Esophagectomy for Esophageal Cancer

Annals of Surgical Oncology - The revised sarcopenia guidelines proposed handgrip strength (HGS) and five-time chair stand test (5-CST) as the primary parameters of muscle function. HGS and 5-CST...     

Maintaining a Surgery Service for Local Hospitals Under the Situation of a Decreasing Number of Surgeons in a Region of Japan

Background

The number of surgeons is decreasing in Japan, leading to the problem of how to maintain a surgery service in local hospitals. We introduce our strategy for supporting ongoing surgical services in regional hospitals by dispatching surgeons temporarily to assist in operations.

Methods

We conducted a questionnaire-based survey at three local hospitals in Tottori and a neighboring prefecture to which surgeons from our department were temporarily dispatched over 5 years from January 2008 to March 2013.

Results

We supported 686 operations at three hospitals over 5 years. The average age of the patients was 72.4 years. Of the diseases treated, 45.1 % were malignant, and 54.9 % were benign. The emergency operation rate was 17.3 %.

Conclusions

Our strategy has produced a continuous surgical service at local hospitals in the face of diminishing numbers of surgeons. We recommend that such a strategy be adopted in other regions in which there are a decreasing number of surgeons and where it is not easy to move patients elsewhere for care.     

Nuclear Notch3 Expression is Associated with Tumor Recurrence in Patients with Stage II and III Colorectal Cancer

Background

The importance of Notch signaling in colorectal cancer (CRC) tumorigenesis has been recently recognized. However, the significance of Notch3 expression and its association with Notch1 expression in CRC is unclear. In the present study, we investigated Notch1 and Notch3 expression in Stage II and III CRC to assess their association with clinicopathological characteristics.

Methods

The protein expression of Notch1 and Notch3 was examined using immunohistochemistry in 305 CRC specimens. Nuclear expression of Notch1 and Notch3 and their associations with clinicopathological characteristics and distant relapse-free survival (dRFS) were evaluated.

Results

Nuclear Notch1 was overexpressed in 37 % of specimen, and nuclear Notch3 in 38 %. Nuclear Notch3 expression correlated with tumor differentiation status (P = 0.0099). Nuclear expression of Notch1 and Notch3 was associated with tumor recurrence (P = 0.0311 and P = 0.0053, respectively). In multivariate analysis, nuclear Notch3 expression [hazard ratio (HR) = 1.71; 95 % confidence interval (CI), 1.06–2.78; P = 0.0271), lymph node metastasis, and venous involvement were independently correlated with dRFS. In subgroup analysis, nuclear Notch3 expression was strongly associated with dRFS in Stage II CRC (HR = 3.47; 95 % CI 1.44–9.22; P = 0.0055). Both nuclear Notch1 and Notch3 were positive in 67 specimens (22 %) and both were negative in 144 specimens (47 %). Coexpression of nuclear Notch1 and Notch3 had an additive effect toward poorer dRFS compared with a negative subtype (HR = 2.48; 95 % CI, 1.41–4.40; P = 0.0019).

Conclusions

Nuclear Notch3 expression might be a novel predictive marker for recurrence in Stage II and III CRC.     

“My Friend Said it was Good LSD”: A Suicide Attempt Following Analytically Confirmed 25I-NBOMe Ingestion

A new class of synthetic hallucinogens called NBOMe has emerged, and reports of adverse effects are beginning to appear. We report on a case of a suicide attempt after LSD ingestion which was analytically determined to be 25I-NBOMe instead. Clinicians need to have a high index of suspicion for possible NBOMe ingestion in patients reporting the recent use of LSD or other hallucinogens.