A novel surgical training simulator for transanal total mesorectal excision

BACKGROUND

The transanal total mesorectal excision (TaTME) approach for rectal cancer has been gaining popularity. Although TaTME requires specific training, the opportunity to obtain this training is limited. We developed the first dry simulator that includes some important structural landmarks to provide training that includes all the procedural steps of TaTME.

METHODS

The model was structured based on a computed tomography scan data. The simulator mimics the rectum and surrounding key anatomical structures. All material components were made of polyvinyl alcohol and stained with various colors to easily identify these anatomical structures while undergoing the training.

RESULTS

Our simulator is compact in its size and can be easily packed, stacked, and stored. The materials mimic the real one and the model allows us to perform the entire step-by-step TaTME procedures with genuine clinical devices from the attachment of operative platform to the anastomosis. We have held the course 24 times to date, with more than 200 surgeons participating not only from domestic hospitals but also from other countries. The result of the satisfaction survey from 65 participants, which was rated from 0 to 10 points, was an average score of 8.6 (± 1.4) points.

CONCLUSIONS

We present the world's first TaTME simulator and believe that it will play an important role for the safe spread of TaTME surgery.

CA1 Nampt knockdown recapitulates hippocampal cognitive phenotypes in old mice which nicotinamide mononucleotide improves

Cognitive dysfunction is one of the most concerning outcomes in global population aging. However, the mechanisms by which cognitive functions are impaired during aging remain elusive. It has been established that NAD⁺ levels are reduced in multiple tissues and organs, including the brain. We found that NAD⁺ levels declined in the hippocampus of mice during the course of aging, and whereas we observed minimal age-related effects on spatial learning/memory capabilities in old mice, we discovered that they developed cognitive hypersensitivity in response to aversive stimulation during contextual fear conditioning tests. This cognitive hypersensitivity appears to be associated with alterations in emotionality (fear/anxiety) and sensory processing (shock sensitivity), rather than reflect genuine conditioning/retention effects, during aging. Supplementation of nicotinamide mononucleotide (NMN) improved the sensory processing aspect of the hypersensitivity and possibly other related behaviors. Specific knockdown of nicotinamide phosphoribosyltransferase (Nampt) in the CA1 region, but not in the dentate gyrus, recapitulates this cognitive hypersensitivity observed in old mice. We identified calcium/calmodulin-dependent serine protein kinase (Cask) as a potential downstream effector in response to age-associated NAD⁺ reduction in the hippocampus. Cask expression is responsive to NAD⁺ changes and also reduced in the hippocampus during aging. Short-term NMN supplementation can enhance Cask expression in the hippocampus of old mice. Its promoter activity is regulated in a Sirt1-dependent manner. Taken together, NAD⁺ reduction in the CA1 region contributes to development of age-associated cognitive dysfunction, aspects of which may be prevented or treated by enhancing NAD⁺ availability through supplementation of NAD⁺ intermediates, such as NMN.

Cognitive dysfunction is one of the most concerning outcomes in global population aging. However, the mechanisms of cognitive impairment during aging remain elusive. We found that in old mice, levels of nicotinamide adenine dinucleotide (NAD⁺), an essential chemical for all living organisms, declined in the hippocampus, a critical part of the brain for memory and learning. We also found that age-associated hypersensitivity in cognitive and behavioral functions (cognitive hypersensitivity) was induced by reduced NAD⁺ availability in the hippocampus. Supplementation of nicotinamide mononucleotide (NMN), a critical chemical that is converted to NAD⁺, is able to mitigate the cognitive hypersensitivity observed in old mice. Our findings provide new insights into how NAD⁺ decline affects age-associated anxiety/depression and how such impairments can be prevented or treated by enhancing NAD⁺.

Impact of different timing of consuming sweet snack on postprandial glucose excursions in healthy women

AIMS

Our aim was to evaluate the acute effect of eating sweet snacks at different times of day on glycaemic parameters in young women without diabetes.

METHODS

In this randomized controlled three-treatment crossover study, 17 women [(means ± SD) age: 21.2 ± 0.8 years, BMI: 20.7 ± 2.5 kg/m2, HbA_1c: 36 ± 2 mmol/mol (5.1 ± 0.2%)] wore flash (continuous) glucose monitoring systems for 7 days. Each participant consumed identical test meals on days 4, 5 and 6, but consumed sweet snacks (baked cake: 498 kcal; 53.6 g of carbohydrate, 8.0 g of protein, 28.0 g of fat) at 12:30 (post-lunch), 15:30 (mid-afternoon) and 19:30 (post-dinner), respectively, on each of those days. Daily glycaemic parameters on those 3 days of snacking at different times of day were compared within-participant.

RESULTS

The mean amplitude of glycaemic excursions (3.54 ± 0.32 vs. 2.73 ± 0.20 mmol/L; P < 0.05), standard deviation of glucose (1.20 ± 0.11 vs. 0.92 ± 0.07 mmol/L; P < 0.05), incremental area under the curve (IAUC) for glucose at 12:00-07:00 (986 ± 89 vs. 716 ± 88 mmol/L × min; P < 0.05) and IAUC at 07:00-10:00 the next day (141 ± 17 vs. 104 ± 12 mmol/L × min; P < 0.05) when the snack was eaten post-dinner were all significantly higher than with mid-afternoon snacking.

CONCLUSION

Eating sweet snacks post-dinner should be avoided because it worsens glucose excursions as well as postprandial glucose levels after both dinner and the following day's breakfast in young healthy (non-diabetic) women.

Consuming snacks mid-afternoon compared with just after lunch improves mean amplitude of glycaemic excursions in patients with type 2 diabetes: A randomized crossover clinical trial

AIMS

Our aim was to explore the acute effects of consuming snacks at different times on glucose excursions in patients with type 2 diabetes (T2D).

METHODS

Seventeen patients with T2D [means±SD: age 67.4±9.4-years; BMI 23.5±3.1kg/m²; HbA_1c 55±6mmol/mol (7.2±1.0%)] were randomly assigned in this crossover study. Each participant wore a continuous glucose monitoring device for 4 days and consumed identical test meals on the second and third days, comprising breakfast at 0700h, lunch at 1200h and dinner at 1900h. Half the participants consumed 75kcal biscuits at 1230h (just after lunch) on the second day and at 1530h (mid-afternoon) on the third day, while the other half consumed snacks at the same times, but vice versa. Each patient's glucose parameters were compared against baseline for the 2days of snacking at different times of day.

RESULTS

Consuming snacks in the mid-afternoon led to significantly lower mean amplitudes of glycaemic excursions (mean±SEM: 5.19±0.48 vs. 6.90±0.69mmol/L, P<0.01; standard deviation: 1.75±0.17 vs. 2.16±0.21mmol/L, P<0.01) and incremental areas under the curve for glucose after dinner (479±76 vs. 663±104mmol/L per min, P<0.01) compared with snacking just after lunch, whereas mean glucose levels did not differ over the 2days.

CONCLUSION

These results suggest that consuming snacks well separated from lunch may be an effective way to suppress postprandial glucose levels and glycaemic excursions.

Activation of a chondrocyte volume-sensitive Cl(-) conductance prior to macroscopic cartilage lesion formation in the rabbit knee anterior cruciate ligament transection osteoarthritis model

OBJECTIVE

The anterior cruciate ligament transection (ACLT) rabbit osteoarthritis (OA) model confers permanent knee instability and induces joint degeneration. The degeneration process is complex, but includes chondrocyte apoptosis and OA-like loss of cartilage integrity. Previously, we reported that activation of a volume-sensitive Cl(-) current (ICl,vol) can mediate cell shrinkage and apoptosis in rabbit articular chondrocytes. Our objective was therefore to investigate whether ICl,vol was activated in the early stages of the rabbit ACLT OA model.

DESIGN

Adult Rabbits underwent unilateral ACLT and contralateral arthrotomy (sham) surgery. Rabbits were euthanized at 2 or 4 weeks. Samples were analyzed histologically and with assays of cell volume, apoptosis and electrophysiological characterization of ICl,vol.

RESULTS

At 2 and 4 weeks post ACLT cartilage appeared histologically normal, nevertheless cell swelling and caspase 3/7 activity were both significantly increased compared to sham controls. In cell-volume experiments, exposure of chondrocytes to hypotonic solution led to a greater increase in cell size in ACLT compared to controls. Caspase-3/7 activity, an indicator of apoptosis, was elevated in both ACLT 2wk and 4wk. Whole-cell currents were recorded with patch clamp of chondrocytes in iso-osmotic and hypo-osmotic external solutions under conditions where Na(+), K(+) and Ca(2+) currents were minimized. ACLT treatment resulted in a large increase in hypotonic-activated chloride conductance.

CONCLUSION

Changes in chondrocyte ion channels take place prior to the onset of apparent cartilage loss in the ACLT rabbit model of OA. Further studies are needed to investigate if pharmacological inhibition of ICl,vol decreases progression of OA in animal models.

Effect of Ethanol Induced Occlusion of the Renal Artery in Rabbit Kidney Implanted with VX2 Carcinoma

The effects of injection of absolute ethanol into the renal artery were investigated in 13 rabbit kidneys previously implanted with VX2 carcinoma. Eight rabbits with implanted tumors served as controls. The effects were evaluated by angiography and histology. Three days after implantation, tumors were demonstrated by angiography as relatively hypovascular areas in the subcapsular cortex of the kidneys. Following angiography, absolute ethanol (0.3 ml/kg) was injected into the renal artery. Repeat angiography with barium sulphate was performed after an additional 3 days (10 ethanol treated animals, 2 controls), 10 days (2 treated, 1 control) or 14 days (1 treated, 0 control). In treated animals the tumors were markedly smaller in comparison with those of the control group. The occlusion procedure, however, did not completely eradicate tumor cells. The histologic study of the implanted tumor confirmed the findings previously reported that viable tumor cells still remained in the peripheral portions of infarcted areas. This study demonstrated the beneficial, though not curative, short-term effects of transcatheter renal artery treatment with absolute ethanol in malignant renal tumors.

Size of Normal Hilar Lymph Nodes Measured in Autopsy Specimens

The normal size of lymph nodes for each region of the hilum was determined by direct measurement of the short and long diameters of each node in the transverse plane of the node and the longitudinal diameter in the vertical plane of the node in 30 adult cadavers. The mean short transverse diameters ranged from 3.2 to 6.4 mm, the mean long transverse diameters ranged from 4.9 to 10.0 mm, and the mean longitudinal diameters ranged from 5.7 to 11.3 mm. The largest mean transverse diameters were found in the anterior upper lobe (AUL) and the inferior interlobar (IIL) regions. We noted a different maximum normal size for lymph nodes in each region of the hilum and determined the standard maximum normal short transverse diameters to be as follows: 12 mm for nodes in the right AUL and IIL regions, 10 mm for nodes in the right superior interlobar region and the left AUL and IIL regions, and 8 mm for nodes in other regions. Both the maximum normal long transverse diameters and the longitudinal diameters showed a wider variation, ranging from 18 to 10 mm and from 20 to 12 mm, respectively.

Sensitization of TRPV1 by protein kinase C in rats with mono-iodoacetate-induced joint pain

OBJECTIVE

To assess the functional changes of Transient receptor potential vanilloid 1 (TRPV1) receptor and to clarify its mechanism in a rat mono-iodoacetate (MIA)-induced joint pain model (MIA rats), which has joint degeneration with cartilage loss similar to osteoarthritis.

METHODS

Sensitization of TRPV1 in MIA rats was assessed by transient spontaneous pain behavior induced by capsaicin injection in knee joints and electrophysiological changes of dorsal root ganglion (DRG) neurons innervating knee joints in response to capsaicin. Mechanisms of TRPV1 sensitization were analyzed by a newly developed sandwich enzyme-linked immunosorbent assay that detects phosphorylated TRPV1, followed by functional and expression analyses of protein kinase C (PKC) in vivo and in vitro, which involves TRPV1 phosphorylation.

RESULTS

Pain-related behavior induced by intra-articular injection of capsaicin was significantly increased in MIA rats compared with sham rats. In addition, capsaicin sensitivity, evaluated by capsaicin-induced inward currents, was significantly increased in DRG neurons of MIA rats. Protein levels of TRPV1 remained unchanged, but phosphorylated TRPV1 at Ser800 increased in DRG neurons of MIA rats. Phosphorylated-PKCɛ (p-PKCɛ) increased and co-localized with TRPV1 in DRG neurons of MIA rats. Capsaicin-induced pain-related behavior in MIA rats was inhibited by intra-articular pretreatment of the PKC inhibitor bisindolylmaleimide I. In addition, intra-articular injection of the PKC activator phorbol 12-myristate 13-acetate increased capsaicin-induced pain-related behavior in normal rats.

CONCLUSION

TRPV1 was sensitized at the knee joint and at DRG neurons of MIA rats through PKC activation. Thus, TRPV1 sensitization might be involved in chronic pain caused by osteoarthritis.

Three-day regimen of oseltamivir for postexposure prophylaxis of influenza in wards

Inpatients who had been in close contact with patients with influenza were given oseltamivir [75mg capsules once daily for adults or 2mg/kg (maximum of 75mg) once daily for children] for three days as postexposure prophylaxis (PEP). The index patients with influenza were prescribed a neuraminidase inhibitor and were discharged immediately or transferred to isolation rooms. The protective efficacy of oseltamivir for three days was 93% overall [95% confidence interval (CI) 53-99%; P=0.023] and 94% for influenza A (95% CI 61-99%; P=0.017), which is comparable to that of seven- to 10-day regimens of oseltamivir as PEP.

Arthrodesis of the ankle using an anterior sliding tibial graft for osteoarthritis secondary to osteonecrosis of the talus

Aims

This retrospective cohort study compared the results of vascularised and non-vascularised anterior sliding tibial grafts for the treatment of osteoarthritis (OA)of the ankle secondary to osteonecrosis of the talus.

Patients and Methods

We reviewed the clinical and radiological outcomes of 27 patients who underwent arthrodesis with either vascularised or non-vascularised (conventional) grafts, comparing the outcomes (clinical scores, proportion with successful union and time to union) between the two groups. The clinical outcome was assessed using the Mazur and American Orthopaedic Foot and Ankle Society (AOFAS) ankle-hindfoot scores. The mean follow-up was 35 months (24 to 68).

Results

The mean outcome scores increased significantly in both groups. In the vascularised graft group, the mean Mazur score improved from 36.9 to 74.6 and the mean AOFAS scale improved from 49.6 to 80.1. In the conventional arthrodesis group, the mean Mazur score improved from 35.5 to 65 and the mean AOFAS scale from 49.2 to 67.6. Complete fusion was achieved in 13 patients (76%) in the vascularised group, but only four (40%) in the conventional group. The clinical outcomes and proportion achieving union were significantly better in the vascularised group compared with the conventional arthrodesis group, although time to union was similar in the two groups. Take home message: Vascularised sliding tibial grafts may be used to achieve arthrodesis in patients with OA of the ankle secondary to osteonecrosis of the talus. Cite this article: Bone Joint J 2016;98-B:359–64.

A new form of surgical treatment for patients with avascular necrosis of the talus and secondary osteoarthritis of the ankle

A new method of vascularised tibial grafting has been developed for the treatment of avascular necrosis (AVN) of the talus and secondary osteoarthritis (OA) of the ankle. We used 40 cadavers to identify the vascular anatomy of the distal tibia in order to establish how to elevate a vascularised tibial graft safely. Between 2008 and 2012, eight patients (three male, five female, mean age 50 years; 26 to 68) with isolated AVN of the talus and 12 patients (four male, eight female, mean age 58 years; 23 to 76) with secondary OA underwent vascularised bone grafting from the distal tibia either to revascularise the talus or for arthrodesis. The radiological and clinical outcomes were evaluated at a mean follow-up of 31 months (24 to 62). The peri-malleolar arterial arch was confirmed in the cadaveric study. A vascularised bone graft could be elevated safely using the peri-malleolar pedicle. The clinical outcomes for the group with AVN of the talus assessed with the mean Mazur ankle grading scores, improved significantly from 39 points (21 to 48) pre-operatively to 81 points (73 to 90) at the final follow-up (p = 0.01). In all eight revascularisations, bone healing was obtained without progression to talar collapse, and union was established in 11 of 12 vascularised arthrodeses at a mean follow-up of 34 months (24 to 58). MRI showed revascularisation of the talus in all patients. We conclude that a vascularised tibial graft can be used both for revascularisation of the talus and for the arthrodesis of the ankle in patients with OA secondary to AVN of the talus.

THE PROGNOSIS OF SKIN CARCINOMA AND MALIGNANT MELANOMA WITH SPECIAL REFERENCE TO THEIR EXTENTS AS REPRESENTED IN TERMS OF T, N, AND M OF UNION INTERNATIONALE CONTRE LE CANCER (UICC)

The prognosis of skin carcinoma and malignant melanoma was studied statistically. One hundred and one cases of basal cell epithelioma (BCE), 93 cases of squamous cell carcinoma (SCC), and 34 cases of malignant melanoma (MM) were studied. No cases of death due to basal cell epithelioma were found. The squamous cell carcinomas and malignant melanomas were classified according to the TNM system into three classes with different prognoses. The first class represents the initial stage, in which cure is expected if treatment is adequate. The second class is the intermediate stage, in which cure is uncertain and the prognosis depends upon the degree of extension. The third class is the late stage, in which distant metastasis is found and in which cure might not be anticipated. Furthermore, the prognosis of previously treated cases was poorer than that of untreated cases. Our findings indicate that early diagnosis and appropriate treatment in the initial stage results in the best prognosis and that the success or failure of the initial treatment has an appreciable influence on the prognosis of skin malignancy.

The importance of NAMPT/NAD/SIRT1 in the systemic regulation of metabolism and ageing

Ageing is associated with a variety of pathophysiological changes, including development of insulin resistance, progressive decline in β-cell function and chronic inflammation, all of which affect metabolic homeostasis in response to nutritional and environmental stimuli. SIRT1, the mammalian nicotinamide adenine dinucleotide (NAD)-dependent protein deacetylase, and nicotinamide phosphoribosyltransferase (NAMPT), the rate-limiting NAD biosynthetic enzyme, together comprise a novel systemic regulatory network, named the 'NAD World', that orchestrates physiological responses to internal and external perturbations and maintains the robustness of the physiological system in mammals. In the past decade, an accumulating body of evidence has demonstrated that SIRT1 and NAMPT, two essential components in the NAD World, play a critical role in regulating insulin sensitivity and insulin secretion throughout the body. In this article, we will summarize the physiological significance of SIRT1 and NAMPT-mediated NAD biosynthesis in metabolic regulation and discuss the ideas of functional hierarchy and frailty in determining the robustness of the system. We will also discuss the potential of key NAD intermediates as effective nutriceuticals for the prevention and the treatment of age-associated metabolic complications, such as type 2 diabetes.

Switching dynamics and linear response spectra of a driven one-dimensional nonlinear lattice containing an intrinsic localized mode

An intrinsic localized mode (ILM) represents a localized vibrational excitation in a nonlinear lattice. Such a mode will stay in resonance as the driver frequency is changed adiabatically until a bifurcation point is reached, at which point the ILM switches and disappears. The dynamics behind switching in such a many body system is examined here through experimental measurements and numerical simulations. Linear response spectra of a driven micromechanical array containing an ILM were measured in the frequency region between two fundamentally different kinds of bifurcation points that separate the large amplitude ILM state from the two low amplitude vibrational states. Just as a natural frequency can be associated with a driven harmonic oscillator, a similar natural frequency has been found for a driven ILM via the beat frequency between it and a weak, tunable probe. This finding has been confirmed using numerical simulations. The behavior of this nonlinear natural frequency plays important but different roles as the two bifurcation points are approached. At the upper transition its frequency coalesces with the driver and the resulting bifurcation is very similar to the saddle-node bifurcation of a single driven Duffing oscillator, which is treated in an Appendix. The lower transition occurs when the four-wave mixing partner of the natural frequency of the ILM intersects the topmost extended band mode of the same symmetry. The properties of linear local modes associated with the driven ILM are also identified experimentally for the first time and numerically but play no role in these transitions.

Gene cloning and characterization of the protein encoded by the Neospora caninum bradyzoite-specific antigen gene BAG1

Neospora caninum is an Apicomplexan parasite that causes repeated abortion and stillbirth in cattle. The aim of this study was to clone the gene encoding the N. caninum orthologue (NcBAG1) of the Toxoplasma gondii bradyzoite-specific protein TgBAG1 and characterize its expression pattern in the parasite. Isolation of the full-length 684-bp gene revealed that it shared 78.3% sequence similarity with TgBAG1. NcBAG1 encodes a predicted protein of 227 amino acids with 80.3% similarity to TgBAG1. A putative signal peptide sequence and an invariant GVL motif characteristic of small heat-shock proteins were identified in the predicted N. caninum amino acid sequence. We expressed the NcBAG1 gene as a recombinant glutathione S-transferase fusion protein (rNcBAG1) in Escherichia coli and used the purified 60 kDa protein to obtain a monoclonal antibody (Mab). rNcBAG1 reacted to Mabs specific for NcBAG1 and TgBAG1. No reaction between the NcBAG1 Mab and N. caninum tachyzoites was observed. Although the predicted molecular mass of NcBAG1 is 25 kDa, Western blot analysis of parasite lysates using the NcBAG1 Mab revealed a cross-reactive protein of approximately 30 kDa. Additionally, immunofluorescence assays using the tachyzoite-specific Mab for NcSAG1 and the bradyzoite-specific Mab for TgBAG1 or NcSAG4 revealed NcBAG1-specific expression in bradyzoites in cultures exposed to sodium nitroprusside, a reagent that increases the frequency of bradyzoites. Interestingly, the NcBAG1 protein was identified in the cytoplasm of the bradyzoite-stage parasites. This preliminary analysis of the NcBAG1 gene will assist investigations into the role of this protein in N. caninum .

Serum antibody to Porphyromonas gingivalis in chronic kidney disease

Potentially significant associations between periodontal disease and chronic kidney disease (CKD) have been reported in recent studies. The aim of this cross-sectional study was to investigate the association between serum antibody to the periodontal pathogen Porphyromonas gingivalis (P. gingivalis) and CKD in 215 Japanese individuals, aged 79 yrs. Serum antibody levels to P. gingivalis were measured by enzyme-linked immunosorbent assay. An elevated serum antibody response was defined as the upper quartile and was compared with the bottom three quartiles. Participants were classified as having CKD when their glomerular filtration rate was between 15 and 59 mL/min/1.73 m(2). A multivariable logistic regression model was used to evaluate the association between elevated antibody status and the presence of CKD. Study participants with an elevated serum antibody to P. gingivalis were 2.6 times more likely to have CKD. The adjusted odds ratio of CKD for participants in the highest quartile of serum antibody to P. gingivalis was 2.59 (95% confidence interval, 1.05-6.34) when compared with others in lower quartiles after simultaneous adjustment for other covariates. In conclusion, the present study suggests that elevated serum antibody to P. gingivalis was significantly associated with decreased kidney function in a community-based cohort of elderly Japanese.

Rho GDP-dissociation inhibitor alpha is associated with cancer metastasis in colon and prostate cancer

Since metastasis is one of the most important prognostic factors in colorectal cancer, development of new methods to diagnose and prevent metastasis is highly desirable. However, the molecular mechanisms leading to the metastatic phenotype have not been well elucidated. In this study, a proteomics-based search was carried out for metastasis-related proteins in colorectal cancer by analyzing the differential expression of proteins in primary versus metastasis focus-derived colorectal tumor cells. Protein expression profiles were determined using a tissue microarray (TMA), and the results identified Rho GDP-dissociation inhibitor alpha (Rho GDI) as a metastasis-related protein in colon and prostate cancer patients. Consequently, Rho GDI may be useful as a diagnostic biomarker and/or a therapeutic to prevent colon and prostate cancer metastasis.

Effect of κ-opioid receptor agonist on the growth of non-small cell lung cancer (NSCLC) cells

BACKGROUND

It is becoming increasingly recognised that opioids are responsible for tumour growth. However, the effects of opioids on tumour growth have been controversial.

METHODS

The effects of κ-opioid receptor (KOR) agonist on the growth of non-small cell lung cancer (NSCLC) cells were assessed by a cell proliferation assay. Western blotting was performed to ascertain the mechanism by which treatment with KOR agonist suppresses tumour growth.

RESULTS

Addition of the selective KOR agonist U50,488H to gefitinib-sensitive (HCC827) and gefitinib-resistant (H1975) NSCLC cells produced a concentration-dependent decrease in their growth. These effects were abolished by co-treatment with the selective KOR antagonist nor-BNI. Furthermore, the growth-inhibitory effect of gefitinib in HCC827 cells was further enhanced by co-treatment with U50,488H. With regard to the inhibition of tumour growth, the addition of U50, 488H to H1975 cells produced a concentration-dependent decrease in phosphorylated-glycogen synthase kinase 3β (p-GSK3β).

CONCLUSION

The present results showed that stimulation of KOR reduces the growth of gefitinib-resistant NSCLC cells through the activation of GSK3β.

Predictors of 5-year mortality in pulmonary Mycobacterium avium-intracellulare complex disease

SETTING

Kyoto, Japan.

OBJECTIVE

To determine predictors of 5-year mortality in pulmonary Mycobacterium avium-intracellulare complex (MAC) disease.

DESIGN

Retrospective study of 164 patients diagnosed with pulmonary MAC disease between 1999 and 2005 and followed for 5 years.

RESULTS

Overall 5-year mortality was 28.0%. Among 117 patients with microbiological outcomes, 54 were treated (treated MAC patients) and 24 were not treated and did not experience sputum culture conversion during follow-up (untreated chronic MAC patients); 39 patients were not treated and experienced sputum culture conversion. Five-year all-cause overall mortality among the 78 patients with definite MAC disease (including treated and untreated chronic MAC patients) was 25.6%. The mortality rate was 33.3% for untreated chronic MAC patients only vs. 22.2% for treated MAC patients (P = 0.30). After adjustment for clinical, microbiological and radiological confounders, independent factors for 5-year mortality were a high Charlson comorbidity index in cases with definite MAC disease (hazard ratio [HR] 1.76) and untreated chronic MAC (HR 3.08), and presence of cavitary lesions in cases with definite MAC disease (HR 1.82) and treated MAC patients (HR 3.91).

CONCLUSION

Patients with cavitary lesions require immediate treatment for sputum culture conversion and to improve their chances of survival.

Experimental observation of the bifurcation dynamics of an intrinsic localized mode in a driven 1D nonlinear lattice

Linear response spectra of a driven intrinsic localized mode in a micromechanical array are measured as it approaches two fundamentally different kinds of bifurcation points. A linear phase mode associated with this autoresonant state softens in frequency and its amplitude grows as the upper frequency bifurcation point is approached, similar to the soft-mode kinetic transition for a single driven Duffing resonator. A lower frequency bifurcation point occurs when the four-wave-mixing partner of this same phase mode intercepts the top of the extended wave branch, initiating a second kinetic transition process.

Low serum bilirubin concentration in haemodialysis patients with Type 2 diabetes

AIMS

Previous studies have implicated reduced serum bilirubin concentrations in the development of cardiovascular disease. The aim of this study was to examine whether bilirubin may explain the high incidence of vascular complications in haemodialysis patients with Type 2 diabetes.

METHODS

We compared serum bilirubin concentrations, as well as other known aetiological risk factors for cardiovascular disease, in 206 Type 2 diabetes patients on haemodialysis with those in 741 Type 2 diabetes patients not receiving haemodialysis, and evaluated the association between serum bilirubin concentration and cardiovascular disease incidence.

RESULTS

Incidences of cardiovascular disease and systolic blood pressure were higher; however, BMI and serum total cholesterol were lower in haemodialysis patients compared with those in patients without haemodialysis. Serum total (0.30 ± 0.10 vs. 0.74 ± 0.26 mg/dl, 0.005 ± 0.002 vs. 0.013 ± 0.004 mmol/l, P < 0.0001) and indirect (0.17 ± 0.08 vs. 0.70 ± 0.23 mg/dl, 0.003 ± 0.001 vs. 0.012 ± 0.004 mmol/l, P < 0.0001) bilirubin were lower in haemodialysis patients compared with those in patients without haemodialysis. Stepwise regression analysis demonstrated that age (β = 0.109, F = 5.959, P < 0.05), duration of diabetes (β = -0.112, F = 6.048, P < 0.05), sex (β = -0.123, F = 8.623, P < 0.05), cardiovascular disease events (β = -0.099, F = 5.131, P < 0.05) and presence of haemodialysis (β = -0.626, F = 201.727, P < 0.01) were independent factors for serum total bilirubin. Logistic regression demonstrated that age (OR 1.089, 95% CI 1.044-1.136; P < 0.0001), duration of diabetes (OR 1.029, 95% CI 1.001-1.059; P = 0.0423), body mass index (OR 1.115, 95% CI 1.001-1.242; P = 0.0487), habit of smoking (OR 2.445, 95% CI 1.046-5.716; P = 0.0391) and serum total bilirubin (OR 0.192, 95% CI 0.037-0.989; P = 0.0484) were independent factors for cardiovascular disease events.

CONCLUSIONS

Low serum bilirubin concentration could be one of the important factors for the high incidence of cardiovascular disease in Type 2 diabetes patients receiving haemodialysis.

Spinal subarachnoid hematoma following spinal anesthesia in a patient with HELLP syndrome

A case of subarachnoid hematoma following spinal anesthesia for cesarean section in a patient with HELLP syndrome is reported. A 39-year-old woman underwent cesarean section under spinal anesthesia for worsening preeclampsia with HELLP syndrome. Despite full recovery from the spinal anesthetic, on the second postoperative day she felt numbness on the posterior aspect of her right leg, noticed she was insensitive to bladder fullness and had mild flaccid paraparesis. Magnetic resonance imaging revealed a spinal subarachnoid hematoma with cauda equina compression. With conservative management she made an almost complete recovery within three months. Serial magnetic resonance imaging showed spontaneous regression of the hematoma. The risk of spinal subarachnoid hematoma following obstetric regional anesthesia is exceedingly small even in a patient with coagulopathy and, to our knowledge, this is only the second reported case following obstetric regional anesthesia. Anesthesia for HELLP syndrome in patients with an adequate platelet count but without disseminated intravascular coagulation is controversial. It is therefore important for clinicians to recognize the symptoms and signs of spinal subarachnoid hematoma to avoid delay in treatment that might result in severe neurological deficit.

Genetic Analysis of Susceptibility to Radiation-induced Apoptosis of Thymocytes in Mice

Genetic control of thymocyte susceptibility to radiation-induced apoptosis was investigated in BALB/cHeA, STS/A and five other strains of mice by counting pyknotic cells in a selected area of thymic cortex on histological specimens after whole-body X-irradiation. Number of dead cells increased almost linearly with doses (range 0.25-0.75 Gy) in BALB/cHeA and STS/A mice. However, dead cell counts in BALB/cHeA mice were more than twice those in STS/A mice at each dose. Of five other strains of mice, C57BL/6N and B10.BR mice exhibited a sensitive phenotype similar to BALB/cHeA mice, while C3H/HeAMsNrs and NFS/N mice showed a resistant phenotype similar to STS/A mice. A/J mice seemed to be rather resistant. A sex difference was not recognized in BALB/cHeA and STS/A mice. Resistance was dominant over susceptibility in the progenies of reciprocal crosses between the two strains, indicating an autosomal inheritance and no maternal effect. Segregation ratio of susceptible phenotype to resistant one in the backcrosses of female (BALB/cHeA x STS/A)F1 mice with male BALB/cHeA mice was not significantly different from 1:1 and all backcrosses of female (BALB/cHeA x STS/A)F1 mice with male STS/A mice exhibited a resistant phenotype. Results suggested that thymocyte susceptibility to radiation-induced apotosis is controlled by one major autosomal allele.

Osteocyte-derived HB-GAM (pleiotrophin) is associated with bone formation and mechanical loading

HB-GAM (also known as pleiotrophin) is a cell matrix-associated protein that is highly expressed in bone. It affects osteoblast function, and might therefore play a role in bone development and remodeling. We aimed to investigate the role of HB-GAM in bone in vivo and in vitro. The bones of HB-GAM deficient mice with an inbred mouse background were studied by histological, histomorphometrical, radiological, biomechanical and mu-CT analyses and the effect of immobilization was evaluated. HB-GAM localization in vivo was studied. MLO-Y4 osteocytes were subjected to fluid shear stress in vitro, and gene and protein expression were studied by subtractive hybridization, quantitative PCR and Western blot. Human osteoclasts were cultured in the presence of rhHB-GAM and their formation and resorption activities were assayed. In agreement with previous reports, the skeletal structure of the HB-GAM knockout mice developed normally. However, a growth retardation of the weight-bearing bones was observed by 2 months of age, suggesting a link to physical activity. Adult HB-GAM deficient mice were characterized by low bone formation and osteopenia, as well as resistance to immobilization-dependent bone remodeling. HB-GAM was localized around osteocytes and their processes in vivo and furthermore, osteocytic HB-GAM expression was upregulated by mechanical loading in vitro. HB-GAM did not affect on human osteoclast formation or resorption in vitro. Taken together, our results suggest that HB-GAM is an osteocyte-derived factor that could participate in mediating the osteogenic effects of mechanical loading on bone.

Alcohol dehydrogenase isozymes in the mouse: genetic regulation, allelic variation among inbred strains and sex differences of liver and kidney A2 isozyme activity

Genetic analysis of a proposed cis-acting temporal locus (Adh-3t), which regulates alcohol dehydrogenase C2 (ADH-C2) activity in mouse epididymis extracts, among F1 (ddN X BALB/c) X ddN male backcross progeny provided evidence for genetic distinctness between the structural (Adh-3) and temporal (Adh-3t) loci on chromosome 3. Genetic analysis also confirmed the close linkage of Adh-1 (encoding liver and kidney ADH-A2) and Adh-3 (encoding stomach ADH-C2) to within 0.3 centimorgans on the mouse genome. Evidence is presented for a proposed closely linked cis-acting temporal locus (designated Adh-lt) for the A2 isozyme (encoded by Adh-1) controlling the activity of this enzyme in mouse kidney extracts, but having no apparent affect on liver and intestine ADH-A2 activities. An extensive survey of the distribution of Adh-1, Adh-3 and Adh-3t alleles among 65 strains of mice is reported--with the exception of two Japanese strains (ddN and KF), linkage disequilibrium between Adh-3 and Adh-3t was observed. Sex differences in mouse liver and kidney ADH-A2 activities were observed, with male/female ratios of approximately 0.6 and 3 respectively for these tissue extracts.

Rapid isolation of intrabody candidates by using an optimized non-immune phage antibody library

Phage antibody library is a promising tool for rapidly creating in vitro single-chain Fv (scFv) antibodies to various antigens. The scFv can also act like a subcellularly-expressed antibody, known as intrabody, and can either be used as a novel research tool or used efficiently for targeted molecular therapy. However, there are only a few existing reports about the successful expression of scFvs as functional antibodies in the cell, mainly because poor quality scFv phage antibody libraries were used to isolate the intrabody clones. The aim of this study was to isolate intrabody-forming scFv clones from the nonimmune scFv phage antibody library we have generated. Using this library, we isolated a scFv clone against the apoptosis-related intracellular protein Bid in two weeks. To evaluate the intrabody-forming quality of this anti-Bid scFv clone, we expressed it in cultured mammalian cells after fusing it with the fluorescent protein Venus. The expression of the soluble form of anti-Bid scFv-Venus fusion protein was confirmed by fluorescence microscopy analysis. These results show that our scFv phage library is not only optimized for antibody production but can also be used to efficiently generate intrabodies.

The specific effect of 2-methoxyestradiol on lymphatic vascular endothelial cells

Lymphatic metastasis of tumors is one of the most important prognostic factors and provides valuable information for decisions on appropriate surgical protocols. Recent studies have demonstrated that lymphangiogenesis of lymphatic vascular endothelial cells into tumors is a key event in lymphatic metastasis. Therefore, control of lymphangiogenesis is a promising strategy for treatment or prevention of tumor metastasis and lymphatic disorders. However, mechanisms of lymphangiogenesis or its specific inhibition are not well-understood. In this study we examined effects of various types of signaling inhibitors on tube formation in human lymphatic microvascular endothelial cells (LECs) and blood microvascular endothelial cells (BECs) in vitro. We found that tube formation of LECs was specifically inhibited by 2-methoxyestradiol (2ME). This observation is of potential benefit in understanding the molecular mechanism of lymphangiogenesis. Furthermore, 2ME could therefore offer specific protection against lymphatic metastasis and lymphangiogenesis-related diseases.