High-Throughput Synthesis of Nanogap-Rich Gold Nanoshells Using Dual-Channel Infusion System

Gold nanoshells have been actively applied in industries beyond the research stage because of their unique optical properties. Although numerous methods have been reported for gold nanoshell synthesis, the labor-intensive and time-consuming production process is an issue that must be overcome to meet industrial demands. To resolve this, we report a high-throughput synthesis method for nanogap-rich gold nanoshells based on a core silica support (denoted as SiO2@Au NS), affording a 50-fold increase in scale by combining it with a dual-channel infusion pump system. By continuously dropping the reactant solution through the pump, nanoshells with closely packed Au nanoparticles were prepared without interparticle aggregation. The thickness of the gold nanoshells was precisely controlled at 2.3-17.2 nm by regulating the volume of the reactant solution added dropwise. Depending on the shell thickness, the plasmonic characteristics of SiO2@Au NS prepared by the proposed method could be tuned. Moreover, SiO2@Au NS exhibited surface-enhanced Raman scattering activity comparable to that of gold nanoshells prepared by a previously reported low-throughput method at the same reactant ratio. The results indicate that the proposed high-throughput synthesis method involving the use of a dual-channel infusion system will contribute to improving the productivity of SiO2@Au NS with tunable plasmonic characteristics.

Recent Studies on Metal-Embedded Silica Nanoparticles for Biological Applications

Recently, silica nanoparticles (NPs) have attracted considerable attention as biocompatible and stable templates for embedding noble metals. Noble-metal-embedded silica NPs utilize the exceptional optical properties of novel metals while overcoming the limitations of individual novel metal NPs. In addition, the structure of metal-embedded silica NPs decorated with small metal NPs around the silica core results in strong signal enhancement in localized surface plasmon resonance and surface-enhanced Raman scattering. This review summarizes recent studies on metal-embedded silica NPs, focusing on their unique designs and applications. The characteristics of the metal-embedded silica NPs depend on the type and structure of the embedded metals. Based on this progress, metal-embedded silica NPs are currently utilized in various spectroscopic applications, serving as nanozymes, detection and imaging probes, drug carriers, photothermal inducers, and bioactivation molecule screening identifiers. Owing to their versatile roles, metal-embedded silica NPs are expected to be applied in various fields, such as biology and medicine, in the future.

Situating the parietal memory network in the context of multiple parallel distributed networks using high-resolution functional connectivity

A principle of brain organization is that networks serving higher cognitive functions are widely distributed across the brain. One exception has been the parietal memory network (PMN), which plays a role in recognition memory but is often defined as being restricted to posteromedial association cortex. We hypothesized that high-resolution estimates of the PMN would reveal small regions that had been missed by prior approaches. High-field 7T functional magnetic resonance imaging (fMRI) data from extensively sampled participants was used to define the PMN within individuals. The PMN consistently extended beyond the core posteromedial set to include regions in the inferior parietal lobule; rostral, dorsal, medial, and ventromedial prefrontal cortex; the anterior insula; and ramus marginalis of the cingulate sulcus. The results suggest that, when fine-scale anatomy is considered, the PMN matches the expected distributed architecture of other association networks, reinforcing that parallel distributed networks are an organizing principle of association cortex.

Silica Encapsulation of Hydrophobic Optical NP-Embedded Silica Particles with Trimethoxy(2-Phenylethyl)silane

Nanoparticles (NP) with optical properties embedded silica particles have been widely used in various fields because of their unique properties. The surfaces of optical NPs have been modified with various organic ligands to maintain their unique optical properties and colloidal stability. Among the surface modification methods, silica encapsulation of optical NPs is widely used to enhance their biocompatibility and stability. However, in the case of NPs with hydrophobic ligands on the surface, the ligands that determine the optical properties of the NPs may detach from the NPs, thereby changing the optical properties during silica encapsulation. Herein, we report a generally applicable silica encapsulation method using trimethoxy(2-phenylethyl)silane (TMPS) for non-hydrophilic optical NPs, such as quantum dots (QDs) and gold NPs. This silica encapsulation method was applied to fabricate multiple silica-encapsulated QD-embedded silica NPs (SiO₂@QD@SiO₂ NPs; QD²) and multiple silica-encapsulated gold NP-embedded silica NPs labeled with 2-naphthalene thiol (SiO₂@Au_2-NT@SiO₂). The fabricated silica-encapsulated NPs exhibited optical properties without significant changes in the quantum yield or Raman signal intensity.

Clinical outcomes of percutaneous coronary intervention and rotational atherectomy using second generation drug eluting stents: a Korean multicentre analysis

Background

The aim of this study was to compare the clinical outcomes of different second generation drug-eluting stents (DES) in patients with calcified coronary lesions who underwent percutaneous coronary intervention using rotational atherectomy.

Methods

This study was based on a multicentre registry which enrolled patients with calcified coronary artery disease who received RA during between January 2010 and October 2019 from 9 tertiary centres in Korea. The primary outcome was target-vessel failure (TVF), defined as the compositae of cardiac death, target-vessel myocardial infarction (MI), and target-vessel revascularisation (TVR). The secondary outcomes were all-cause death, cardiac death, target vessel MI, TVR, cardiovascular accident, stent thrombosis, and total bleeding.

Results

540 patients who underwent PCI after RA were enrolled and followed up for a median period of 16.1 months. From this registry, 439 patients who were treated using second generation DES were selected for further analysis. They were divided into four groups based on the characteristics of the stents used during the procedure. [Group I cobalt-chromium sirolimus eluting stent (CoCr-SES): Ultimaster 48 & Orsiro 30, Group II platinum-chromium everolimus eluting stent (PtCr-EES): Synergy 93 & Promus 70, Group III cobalt-chromium everolimus eluting stent (CoCr-EES): Xience 105, Group IV zotarolimus eluting stent (ZES): Resolute 93] There was no inter-group difference in procedural success rates, and the primary outcome of TVF showed no difference across the four groups (I: 10.3%, II: 13.5%, III: 13.3%, IV: 15.1%, log-rank p=0.922). Even after multivariate Cox regression analysis, there was no significant difference in TVF, or the secondary outcomes of all-cause death, cardiac death, target vessel MI, TVR, cardiovascular accident, stent thrombosis, and total bleeding.

Conclusions

There was no difference in procedural success rates and clinical outcomes between four different types of second-generation DES (CoCr-SES, PtCr-EES, CoCr-EES, ZES) in patients who underwent PCI using RA.

Funding Acknowledgement

Type of funding sources: None.

Lilac flower-shaped ZnCo2O4electrocatalyst for efficient methanol oxidation and oxygen reduction reactions in an alkaline medium

A ZnCo₂O₄electrocatalyst for the efficient MOR and ORR.

Endovascular treatment of transverse-sigmoid sinus dural arteriovenous malformations presenting as pulsatile tinnitus

Transverse-sigmoid sinus dural arteriovenous malformations (DAVM) are uncommon vascular lesions for which complete cure may be difficult to obtain. A wide variety of treatments for these lesions include observation, arterial compression, surgical resection, and endovascular embolization. We propose that transverse-sigmoid sinus DAVM can be completely cured by occluding the ipsilateral dural sinus with detachable balloon and Guglielmi detachable coils (GDC) coils before arterial feeder embolization with histoacryl. Three patients who presented with pulsatile tinnitus and normal magnetic resonance imaging (MRI) studies underwent angiography, which demonstrated transverse-sigmoid sinus DAVM. All three patients wer treated with retrograde transvenous sinus embolization with complete occlusion of the transverse-sigmoid sinus with detachable balloons and GDC coils with preservation of the vein of Labbé. Subsequently, the various feeders from the external carotid artery were embolized. The tentorial arteries arising from the ipsilateral internal carotid arteries were not embolized in any of the cases, which were still contributing to the DAVM. Complete cure with thrombosis of the tentorial branch of the internal carotid artery (ICA) was seen on follow-up angiogram 1 day after embolization in one patient and on 4-week and 6-week follow-up angiograms in the other two patients. Complete occlusion of the transverse sinus proximal to the vein of Labbé, in spite of incomplete arterial feeder embolization, can result in complete cure of the transversesinus dural AVF if adequate time is given for the remaining feeders to occlude, once the fistula is obliterated.

Twelve testable hypotheses on the geobiology of weathering

Critical Zone (CZ) research investigates the chemical, physical, and biological processes that modulate the Earth's surface. Here, we advance 12 hypotheses that must be tested to improve our understanding of the CZ: (1) Solar-to-chemical conversion of energy by plants regulates flows of carbon, water, and nutrients through plant-microbe soil networks, thereby controlling the location and extent of biological weathering. (2) Biological stoichiometry drives changes in mineral stoichiometry and distribution through weathering. (3) On landscapes experiencing little erosion, biology drives weathering during initial succession, whereas weathering drives biology over the long term. (4) In eroding landscapes, weathering-front advance at depth is coupled to surface denudation via biotic processes. (5) Biology shapes the topography of the Critical Zone. (6) The impact of climate forcing on denudation rates in natural systems can be predicted from models incorporating biogeochemical reaction rates and geomorphological transport laws. (7) Rising global temperatures will increase carbon losses from the Critical Zone. (8) Rising atmospheric P(CO2) will increase rates and extents of mineral weathering in soils. (9) Riverine solute fluxes will respond to changes in climate primarily due to changes in water fluxes and secondarily through changes in biologically mediated weathering. (10) Land use change will impact Critical Zone processes and exports more than climate change. (11) In many severely altered settings, restoration of hydrological processes is possible in decades or less, whereas restoration of biodiversity and biogeochemical processes requires longer timescales. (12) Biogeochemical properties impart thresholds or tipping points beyond which rapid and irreversible losses of ecosystem health, function, and services can occur.

Microbial diversity and population dynamics of activated sludge microbial communities participating in electricity generation in microbial fuel cells

In this study, we performed microbial community analysis to examine microbial diversity and community structure in microbial fuel cells (MFCs) seeded with activated sludge from a municipal wastewater treatment plant in South Korea. Because anode-attached biofilm populations are particularly important in electricity transfer, the ecological characteristics of anode-attached biofilm microbes were explored and compared with those of microbes grown in suspension in an anode chamber. 16S rDNA-based community analysis showed that the degree of diversity in anode-attached biofilms was greater than that of the originally seeded activated sludge as well as that of the suspension-grown microbes in the anode bottle. In addition, Bacteroidetes and Clostridia grew preferentially during MFC electricity generation. Further phylogenetic analysis revealed that the anode biofilm populations described in this work are phylogenetically distant from previously characterized MFC anode biofilm microbes. These findings suggest that a phylogenetically diverse set of microbes can be involved in the electricity generation of MFC anode compartments, and that increased microbial diversity in anode biofilms may help to stabilize electricity production in the MFC.

Clinical implication of distinction from clinical features and treatment outcome of malignant lymphoma in Korean childhood and young adult

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Background: The Clinicopathologic features of malignant lymphomas vary to geography and differ to age. The goal of this study was to find the implication of distinction from biology, clinical features and treatment outcome of malignant lymphoma in childhood and young adult. Methods: We analysed the clinical features including age, gender, histologic type, and treatment outcome of 294 children and young adults during 13-year period (from May 1993 to November 2005) in Samsung medical center and compared our study to all age group and western childhood and adolescence group on clinical features or treatment outcome in malignant lymphoma. Results: Median age at diagnosis was 20.7 years (range: 0.1–30.1 years). Male to female ratio was 1.37:1, Of 294 cases, there were 248 cases of non-hodgkin’s lymphoma (NHL) (84.3%) and 44 cases of hodgkin’s disease (HD) (15%). This rate was significantly different to rate of all age group (HD= 5.3%) (p=0.001). Of 248 cases of non-hodgkin’s lymphoma, 134 cases (54.0%) were B-lineage and 113 cases (45.6%) were T- or NK-cell lineage. Our study group had higher rates of T- or NK-cell NHL compared to all age group (p=0.001) and western group (p=0.001). Among 248 cases of NHL, the most common histologic type was diffuse large cell lymphoma (DLBL) in our study group. Burkitt’s lymphoma (BL) was the most common histologic types in Western study group. 5-year survival rate (5YSR) was 80.4% and was superior for BL and was inferior for NK/T cell lymphoma. However male T-LBL patients had better outcome in western study group. NHL and T-cell NHL had significantly worse outcomes than HD and B-cell NHL (p=0.049, 0.001, respectively). Comparing age-groups 0–10, 10–20 and 20–30, 5YSR was inferior for the oldest patients only in NHL-, T-cell NHL- and T-cell LBL-groups. Conclusions: Our study suggested environmental and genetic factor was associated with the development of malignant lymphoma.

No significant financial relationships to disclose.

Serum cytokine profiles in patients with Plasmodium vivax malaria: a comparison between those who presented with and without thrombocytopenia

One of the peculiar features of Plasmodium vivax malaria in South Korea is the surprisingly high frequency of thrombocytopenia. The mechanism by which this malaria-related thrombocytopenia develops and its role in the pathology and progress of human infection with P. vivax have not yet been completely understood. In the present study, the serum cytokine profiles of cases of P. vivax malaria who presented with thrombocytopenia were compared with those of similar cases who did not have thrombocytopenia at presentation. The subjects were the 94 consecutive cases of P. vivax malaria who presented at five hospitals in South Korea (all near the Demilitarized Zone) between May 2000 and October 2002, 47 of whom had thrombocytopenia at presentation. When mean values and (S.E.) were compared, the thrombocytopenic patients were found not only to be generally older than the non-thrombocytopenic [25.3 (1.1) v. 21.3 (0.18) years; P < 0.001] but also to have presented with higher serum concentrations of aspartate aminotransferase [77.6 (16.6) v. 32.3 (7.4) U/litre; P < 0.0001], alanine aminotransferase [96.7 (19.0) v. 44.7 (12.0) U/litre; P = 0.0001], interleukin-1 [49.9 (7.4) v. 23.7 (5.1) pg/ml; P < 0.001], interleukin-6 [174.9 (26.4) v. 57.3 (14.6) pg/ml; P = 0.001], interleukin-10 [308.2 (39.6) v. 137.9 (23.1) pg/ml; P < 0.002] and transforming growth factor-beta [1134.3 (387.5) v. 416.6 (183.8) pg/ml; P < 0.0001], and higher levels of parasitaemia [4345.7 (966.6) v. 1443.8 (222.7) parasites/microl; P = 0.03). The non-thrombocytopenic patients, however, had relatively high total leucocyte counts [5.8 (0.24) v. 5.4 (0.66) leucocytes/nl; P = 0.03]. The thrombocytopenia associated with P. vivax malaria in South Korea therefore appears to be associated with elevated serum concentrations of both pro- and anti-inflammatory cytokines. To define the role of each cytokine in the development of thrombocytopenia during the course of acute P. vivax malaria, further prospective studies are needed.

The cytotoxic effect of methotrexate loaded bone cement on osteosarcoma cell lines

We mixed various amounts of methotrexate with bone cement and measured the absorbance daily for 4 weeks. The cytotoxic effects on SaOS2 and MG63 osteosarcoma cells were examined by the MTT assay, and analysed according to the methotrexate concentration and the elapsed time. The amount of eluted methotrexate was greatest during the first day, and then decreased rapidly reaching a plateau in the third week. The number of viable tumour cells decreased significantly after 72 h, and they were hardly seen after 1 week.

DDB2 induces nuclear accumulation of the hepatitis B virus X protein independently of binding to DDB1

The hepatitis B virus (HBV) X protein (HBx) is critical for the life cycle of the virus. HBx associates with several host cell proteins including the DDB1 subunit of the damaged-DNA binding protein DDB. Recent studies on the X protein encoded by the woodchuck hepadnavirus have provided correlative evidence indicating that the interaction with DDB1 is important for establishment of infection by the virus. In addition, the interaction with DDB1 has been implicated in the nuclear localization of HBx. Because the DDB2 subunit of DDB is required for the nuclear accumulation of DDB1, we investigated the role of DDB2 in the nuclear accumulation of HBx. Here we show that expression of DDB2 increases the nuclear levels of HBx. Several C-terminal deletion mutants of DDB2 that fail to bind DDB1 are able to associate with HBx, suggesting that DDB2 may associate with HBx independently of binding to DDB1. We also show that DDB2 enhances the nuclear accumulation of HBx independently of binding to DDB1, since a mutant that does not bind DDB1 is able to enhance the nuclear accumulation of HBx. HBV infection is associated with liver pathogenesis. We show that the nuclear levels of DDB1 and DDB2 are tightly regulated in hepatocytes. Studies with regenerating mouse liver indicate that during late G1 phase the nuclear levels of both subunits of DDB are transiently increased, followed by a sharp decrease in S phase. Taken together, these results suggest that DDB1 and DDB2 would participate in the nuclear functions of HBx effectively only during the late-G1 phase of the cell cycle.

Association between insulin-like growth factor-2 and metastases after transcatheter arterial chemoembolization in patients with hepatocellular carcinoma: a prospective study

BACKGROUND

Hypoxia up-regulates insulin-like growth factor-2 (IGF-2) and thus stimulates the growth of hepatocellular carcinoma (HCC) cells. In the current study, the authors prospectively evaluated changes in plasma IGF-2 levels in HCC patients after transcatheter arterial chemoembolization (TACE), which usually results in hypoxic insult to liver tissue. The authors also examined the association between changes in plasma IGF-2 levels after TACE and HCC progression, especially in relation to metastasis.

METHODS

Plasma IGF-2 levels were measured before and 4 weeks after TACE in 46 patients with HCC. Three months after TACE, the patients were evaluated for the occurrence of metastatic HCC.

RESULTS

In 13 of the 46 patients, post-TACE plasma IGF-2 levels decreased by > 20% (Group 1) compared with their basal levels; in 18 patients, the IGF-2 levels changed within 20% (Group 2) and in 15 patients the IGF-2 levels increased by > 20% (Group 3). Plasma IGF-2 levels had a tendency to increase in patients with large-sized tumors, high serum alpha-fetoprotein (AFP) levels, and the heterogeneous uptake of iodized oil. Metastatic foci were found in 9 patients in Group 3 (60%), in contrast to only 3 patients in Group 2 (17%) and in none of the patients in Group 1 (P = 0.001). On multivariate analysis, higher Child-Pugh scores and increased plasma IGF-2 levels (Group 3) were found to be independent risk factors for metastasis.

CONCLUSIONS

Increased plasma IGF-2 levels after TACE, which are common in patients with large-sized tumors and high serum AFP levels, appear to be associated with the occurrence of metastatic HCC after TACE.

Postmenopausal obesity as a breast cancer risk factor according to estrogen and progesterone receptor status (Japan)

There have been inconsistent results on the association of postmenopausal obesity with breast cancer risk according to the estrogen (ER) and/or progesterone receptor (PR) status in the breast tissue, and this requires further evaluation. This study was designed to assess whether postmenopausal obesity differs according to receptor status. Information on risk factors was obtained from 1154 breast cancer cases and 21714 controls at Aichi Cancer Center Hospital, Nagoya, Japan between 1988 and 1992. The receptor status was known for 40% of cases. Obese postmenopausal women showed an increased risk of breast cancer (odds ratio (OR) for 5 kg of current weight=1.17, 95% confidence interval (CI)=1.10-1.25; OR for 1 kg/m(2) of body mass index (BMI)=1.07, 95% CI=1.04-1.10). The elevated OR was strongest for ER-positive, as well as with PR-positive, breast cancer among postmenopausal women who had a high BMI. The risk did not differ significantly according to ER status. However, obesity indices among postmenopausal women differed with borderline significance according to PR status. These results are consistent with the hypothesis that there is a gradient of risk for postmenopausal obesity according to hormonal receptor status, at least for PR status, although this was not statistically significant.

[Recurrence of cerebral aneurysms in the long-term follow-up after aneurysm surgery]

We investigated late aneurysmal recurrence in 71 patients who underwent direct operations for intracranial aneurysms during the period from 1981 to 1988 and were under 50 years old at the time of operation with ADL rating of 1 or 2 at discharge. And out of the 71 patients, four had already sustained reattack of SAH and been confirmed to have recurrent anuerysms. Another two had been diagnosed as harboring unruptured recurrent aneurysms. Cerebral angiography was carried out for nine patients in the remaining 63, revealing aneurysmal recurrence in four patients. Overall, 14 recurrent aneurysms, 11 de novo and 3 regrowth aneurysms, have been found in 10 patients. Considering the high risk of aneurysmal recurrence, postoperative long-term follow-up including MRA and angiography is mandatory, especially for relatively young patients.

Characteristics of lung cancer in Korea, 1997

The high proportion of smokers and the incidence of advanced, unresectable lung cancer in Korea were examined to aid the development of a national anti-smoking program and the early detection of lung cancer. Koreans are a single racial group with a high smoking rate among men and a contrastingly low smoking rate among women. This report documents a retrospective investigation conducted by The Korean Academy of Tuberculosis and Respiratory Disease into the characteristics of all lung cancers diagnosed between 1 January 1997 and 31 December 1997 in Korea. Among the 3794 patients included in this study, 76.8% were smokers and, in particular, 89.8% of the males were smokers. Squamous cell carcinoma was the most frequent type of lung cancer encountered (44.7%), followed by adenocarcinoma (27.9%). The smoking rate in the case of adenocarcinoma was significantly lower than that found in both squamous cell carcinoma and small cell cancer. The most common symptom was a cough. Only 7.2% of patients were asymptomatic. Bronchoscopic biopsy has a primary role in the diagnosis of squamous cell carcinoma and small cell cancer, but percutaneous needle biopsy has a more important role in the case of adenocarcinoma. Two-thirds of the nonsmall cell lung cancer patients were detected in the unresectable advanced stages (IIIB and IV). In contrast to other countries, squamous cell carcinoma is still the most frequent type of lung cancer in Korea. The high proportion of smokers and the incidence of advanced, unresectable lung cancer at diagnosis have urged development of a national anti-smoking program to promote the cessation of smoking and the early detection of lung cancer.

Randomized, placebo-controlled study of tolcapone in patients with fluctuating Parkinson disease treated with levodopa-carbidopa. Tolcapone Fluctuator Study Group III

OBJECTIVE

To assess the efficacy and tolerability of the catechol-O-methyltransferase inhibitor tolcapone in reducing "off/on" fluctuations in levodopa-treated parkinsonian patients.

DESIGN

A randomized, double-blind, placebo-controlled, parallel-group study.

SETTING

Fifteen Parkinson disease clinics.

PATIENTS

Two hundred fifteen referred outpatients with Parkinson disease who showed predictable end-of-dose motor fluctuations that were not controlled by a stable levodopa-carbidopa (Sinemet) regimen of at least 4 weeks' duration.

INTERVENTIONS

In addition to their usual levodopa-carbidopa regimen, patients received placebo or tolcapone, 100 or 200 mg, 3 times daily orally for 6 weeks.

PRIMARY OUTCOME MEASURE

Change in daily off/on time.

RESULTS

Tolcapone, 100 and 200 mg 3 times daily, reduced off time by 2.0 and 2.5 hours per day, respectively, and increased on time by 2.1 and 2.3 hours per day, respectively (P<.001 vs placebo). Investigators' global measures of disease severity indicated that significantly more tolcapone-treated patients had reduced wearing off and symptom severity (P<.001 vs placebo). No significant change in quality-of-life measures occurred. Clinical improvements occurred despite a reduction in total daily levodopa dose of 185.5 mg (23%) in the tolcapone, 100 mg 3 times daily, group and 251.5 mg (29%) in the 200 mg 3 times daily group. Principal adverse events (mainly dyskinesia and nausea) were levodopa related, were not treatment limiting, and were seldom reported as reasons for withdrawal. The frequency of withdrawals because of adverse events was similar in all groups (3% to 7%).

CONCLUSIONS

Tolcapone was well tolerated and substantially increased on time and reduced off time in patients with fluctuating Parkinson disease. Additionally, levodopa requirements were significantly decreased.

Familial cervical spondylosis. Case report

Cervical spondylosis is a disease that is often attributed to aging and considered the result of degenerative changes in the spine. The idea that there is a genetic predisposition to develop diseases of the skeletal elements of the spine has been discussed previously, but has never been proven conclusively. The authors report three cases of severe cervical spondylosis in patients who are first-degree relatives: a mother and her two sons. All three individuals had cervical disc herniations and stenosis at C3-4, C4-5, C5-6, and C6-7, and all three required decompressive procedures. The location and degree of cervical spondylosis were as similar among these three patients as they have been in identical twins reported in other studies. Such familial inheritance of cervical spondylosis has been reported only once. The existence of familial cervical spondylosis is not an unrealistic proposal because other studies have shown that genetics determines the shape of one's spine and that similar spines tend to degenerate in similar ways. Therefore, genetic counseling for a family such as the one reported here may prove to be of great benefit to warn siblings that they are at high risk for cervical spine injury. However rare it might be, familial cervical spondylosis may be a phenomenon that any spine surgeon should suspect in a family with cervical spine abnormalities found in several members.

Prospective temporal analysis of the onset of preinfarction angina versus outcome: an ancillary study in TIMI-9B

BACKGROUND

The timing of onset of angina before myocardial infarction in relation to outcome is unknown.

METHODS AND RESULTS

We prospectively determined the importance of the time of onset of preinfarction angina in relation to 30-day outcomes in the TIMI-9B study from standardized forms. Of the 3002 patients entered into the study, 425 reported angina before their myocardial infarction. Patients with angina onset within 24 hours of infarction had a lower 30-day cardiac event rate (mortality, recurrent myocardial infarction, heart failure, or shock) at 4% than those with onset of angina >24 hours (17%; P=.030). A history of any angina alone was not associated with reduced event rate. Peak creatine kinase levels tended to be lower in the group with angina within 24 hours. These benefits were not due to higher rates of use of antianginal medicines or aspirin and were not a consequence of differences in baseline characteristics or disease states (hypertension, hypercholesterolemia) among subgroups.

CONCLUSIONS

These temporal observations are consistent with the concept of preconditioning by preinfarction angina but do not rule out other mechanisms.

A high-risk group for prostatism: a population-based epidemiological study in Korea

OBJECTIVE

To evaluate the effect of sociodemographic, dietary and physical factors on prostatism in Korean men aged 50 and over.

SUBJECTS AND METHODS

A community-based cross-sectional epidemiological study was performed in Yonchon County, Korea. The Korean version of the International Prostate Symptom Score (IPSS) was used to assess the severity of prostatism. Data on occupation, marital status, education, smoking habits, alcohol intake, daily consumption of nutrients, body mass index, abdominal circumference, waist-to-hip ratio, blood pressure, serum glucose, cholesterol, triglyceride and high-density lipoprotein (HDL) levels were analysed. The age-adjusted relative risk of these factors was calculated for moderate to severe prostatism (IPSS > or = 8). A multivariate analysis of all significant factors was performed to examine the joint effect of risk factors.

RESULTS

Of 514 subjects, 119 (23.2%) had moderate to severe prostatism, the risk for which was related to age and alcohol consumption; waist-to-hip ratio (which represents the degree of abdominal obesity) and the serum level of HDL showed a biphasic association with prostatism in the multivariate analysis.

CONCLUSION

In addition to previously reported risk factors, these data suggest that there might be an association between the development of prostatism and abnormal lipid metabolism.

An Investigation of the Safety of Midazolam Use in Hospital

OBJECTIVE

To investigate whether an association exists between midazolam use and serious cardiorespiratory events or death.

DESIGN

Retrospective analysis of data in an inpatient record linkage database, collected between March 1986 and October 1987 from 14 hospitals in the United States.

PATIENTS

A cohort of 19,112 patients who received injectable midazolam or diazepam on the same day that a medical procedure was performed.

MAIN OUTCOME MEASURES

An attempt was made to identify suspected serious cardiorespiratory adverse events and deaths that occurred within 24 h of study-drug administration. Death rates within 24 h following study-drug administration were compared between patients who received injectable midazolam and those who received injectable diazepam.

RESULTS

Validation analysis of the information in the computerized record linkage database indicated that serious cardiac and respiratory adverse events that occurred within 24 h of study-drug administration could not be reliably identified. Therefore, a comparison of the serious cardiorespiratory adverse event rates following administration of midazolam versus diazepam could not be made. Death rates within 24 h of study-drug administration could be evaluated. For the cohort as a whole, the death rate was significantly lower among patients who received midazolam than among those who received diazepam (0.76% versus 1.93%, p<0.01). This difference remained statistically significant, after adjusting for age, sex, comorbidity diagnosis, concomitant drug use, type of medical procedure, and hospital size and teaching capability.

CONCLUSIONS

The results suggest that there is no increased risk of death associated with midazolam administration when compared to diazepam administration for endoscopic, conscious sedative, and general anesthetic procedures in hospitals.

Changes of the plasma endothelin in adaptation to increased salt intake in rats

OBJECTIVES

Roles for vascular endothelial hormones in body fluid balance have been variously suggested. The present study was aimed at investigating whether the plasma endothelin is altered in responses to acute and chronic perturbations in body fluid balance.

METHODS

Effects of intravenous infusion of MG-nitro-L-arginine methyl ester (L-NAME), a competitive inhibitor of endothelium-derived nitric oxide (NO) synthesis, on urinary excretion, blood pressure and plasma levels of endothelin were examined in rats kept on either normal or high-salt diet for two weeks. The plasma endothelin levels in response to an acute extracellular volume expansion (VE) were also determined in normal and 2-kidney, 1 clip (2K1C) hypertensive rats.

RESULTS

L-NAME (20 and 200 micrograms.kg(-1) per min) elicited diuretic and natriuretic effects in association with increased blood pressure both in normal and high-salt rats. In high-salt rats, however, the urinary response to L-NAME was attenuated and the pressor response was augmented compared with the control. High-salt intake per se caused a small, but significant, increase of the plasma endothelin. L-NAME (200 micrograms(-1) per min) markedly increased the plasma endothelin was also marginally increased following VE, the magnitude of which did not differ between the normal and 2K1C rats.

CONCLUSION

These results suggest that the endothelin system takes part in adaptation to increased salt-intake. Another evidence indicating a negative modulation of NO on the release of endothelin is also provided.