Value of thrombin-antithrombin III complexes in major orthopedic surgery: relation to the onset of venous thromboembolism.

This study evaluated (a) the possible changes of plasma levels of thrombin-antithrombin III complexes during hospitalization to predict venous thromboembolism in patients undergoing elective total hip replacement and (b) the sensitivity and specificity of thrombin-antithrombin III complexes in the late incidence of deep vein thrombosis when these patients are discharged from the hospital. In 50 consecutive patients (18 men, mean age = 63 ± 8 years) a venous blood sample was obtained from each patient before surgery and postsurgery on days 5 ± 2, 9 ± 2, and 45 to evaluate the thrombin-antithrombin III complexes by the enzyme-linked immunosorbent assay as a part of a larger surveillance program. Six of 50 patients devel oped deep vein thrombosis, diagnosed by phlebography on the 45th day postsurgery. From the day before until the ninth day after surgery, mean values of the thrombin-antithrombin III complexes increased to a greater extent in patients with deep vein thrombosis than in those without, although the differences were not significant (from 14.8 ± 11.2 ng/mL to 36.2 ± 19.1 ng/mL in the former group and from 13.6 ± 3.3 ng/mL to 22.4 ± 5.1 ng/mL in the latter, p = NS). On the 45th day after surgery the mean value of the thrombin-antithrombin III com plexes reduced less in patients with deep vein thrombosis (up to 9.9 ± 1.9 ng/mL and to 25.2 ± 17.2 ng/mL, respectively, p = NS). In addition, thrombin-antithrombin III complexes re mained over the level reached on the fifth day only in the patients who developed deep vein thrombosis. On the 45th day after surgery, thrombin-antithrombin III complexes exhibited a sensitivity of 17%, a specificity of 86%, and an accuracy of 78% in differentiating the presence and absence of deep vein thrombosis as compared with phlebography. We conclude that after total hip replacement (a) serial measurement of the throm bin-antithrombin III complexes does not appear helpful in pre dicting venous thromboembolism during hospitalization, and (b) measurement of thrombin-antithrombin III complexes has a low diagnostic accuracy in diagnosing delayed deep vein thrombosis. However, the greater and persistent increase of thrombin-antithrombin III complexes level in patients who de veloped deep vein thrombosis may deserve further investiga tions

INDURIMENTO SUPERFICIALE DI LEGHE DI TITANIO MEDIANTE TRATTAMENTI TERMICI DI DIFFUSIONE DI Ni

In questo lavoro sono stati ottenuti rivestimenti di Ni elettrolitico e NiB electroless su campioni di titanio puro e sulla lega Ti-6Al-4V. Questi campioni dopo la deposizione sono stati sottoposti a trattamenti termici di diffusione a temperature inferiori e superiori alla temperatura di trasformazione allotropica del titanio e della lega per la durata di 1 h. E’ stato quindi analizzato l’effetto della temperatura sulla diffusione del Ni e del B all’interno del substrato e sulla profondità di indurimento dei campioni mediante analisi al SEM, EDS, XRD, GDOS e prove di microdurezza. Dopo il trattamento di 1h a temperatura superiore alla temperatura ?-transus (1000° C) nel campione di titanio CP si ha la formazione di uno strato di intermetallici NiTi e NiTi2 per uno spessore 20 ?m con valori di durezza di 1000 HV0,1 ed una zona di diffusione di 300-400 ?m con valori di durezza di 300 HV0,1. Per quanto riguarda la lega Ti6Al4V i trattamenti termici al di sopra della ? transus permettono di raggiungere durezze 1000 HV0,1, dovute alla formazione degli intermetallici NiTi e NiTi2 . I migliori risultati, ottenuti, sia per il titanio puro che per la lega, con il trattamento termico effettuato a temperatura superiore alla ? transus, sono da attribuirsi alla maggiore velocità di diffusione indotta sia dalla temperatura che dalla struttura ccc che il titanio assume a temperature superiori alla ? transus

Indurimento superficiale di leghe di alluminio mediante diffusione di rame

Lo scopo di questo lavoro è quello di sviluppare un processo per incrementare la durezza superficialedelle leghe di alluminio 2024 e 7075 mediante trattamenti di diffusione di rame, depositato elettroliticamentesulla superficie. I trattamenti diffusivi sono stati effettuati in forno in atmosfera inerte a temperaturecomprese nell’intervallo 470-500 °C per un tempo massimo di 24 h, seguiti da trattamenti di solubilizzazionee invecchiamento. I campioni sono stati caratterizzati mediante analisi al microscopio ottico (OM),microscopia elettronica a scansione (SEM), diffrazione a raggi X (XRD) e misure di microdurezza Vickers.La lega 2024, in seguito ai trattamenti di diffusione del rame condotti a temperature prossime ai 495 °C,raggiunge una durezza superficiale di 500 HV0,1, contro 80 HV0,1 del cuore del campione.Ciò è dovuto alla formazione dell’intermetallico Al2Cu. Il trattamento di invecchiamento non influenzalo spessore di diffusione che rimane di circa 50 ?m, bensì modifica la durezza in maniera diversa a secondache l’invecchiamento sia naturale o artificiale. I trattamenti di diffusione condotti sulla lega 7075 atemperature prossime a 500 °C provocano la diffusione del rame fino ad una profondità di 600 ?m e causanouna parziale fusione degli intermetallici superficiali, non permettendo di ottenere un aumento significativodella durezza superficiale. Abbassando la temperatura del trattamento diffusivo (470 °C), la zona interessatadalla diffusione del rame è di circa 100 ?m con una durezza di 860 HV0,1, dovuta alla formazione diintermetallici Al-Cu e Zn-Cu. Anche in questo caso, il successivo invecchiamento artificiale non varia lospessore di diffusione, ma porta ad una diminuzione della durezza superficiale a valori attorno a 500 HV0,1

Dimethyl-2-oxoglutarate improves redox balance and mitochondrial function in muscle pericytes of individuals with diabetes mellitus

Aims/hypothesis Treatment of vascular complications of diabetes remains inadequate. We reported that muscle pericytes (MPs) from limb muscles of vascular patients with diabetes mellitus display elevated levels of oxidative stress causing a dysfunctional phenotype. Here, we investigated whether treatment with dimethyl-2-oxoglutarate (DM-2OG), a tricarboxylic acid cycle metab- olite with antioxidant properties, can restore a healthy metabolic and functional phenotype. Methods MPs were isolated from limb muscles of diabetes patients with vascular disease (D-MPs) and from non-diabetic control participants (ND-MPs). Metabolic status was assessed in untreated and DM-2OG-treated (1 mmol/l) cells using an extracellular flux analyser and anion-exchange chromatography–mass spectrometry (IC-MS/MS). Redox status was measured using commercial kits and IC-MS/MS, with antioxidant and metabolic enzyme expression assessed by quanti- tative RT-PCR and western blotting. Myogenic differentiation and proliferation and pericyte–endothelial interaction were assessed as functional readouts. Results D-MPs showed mitochondrial dysfunction, suppressed glycolytic activity and reduced reactive oxygen species- buffering capacity, but no suppression of antioxidant systems when compared with ND-MP controls. DM-2OG supple- mentation improved redox balance and mitochondrial function, without affecting glycolysis or antioxidant systems. Nonetheless, this was not enough for treated D-MPs to regain the level of proliferation and myogenic differentiation of ND-MPs. Interestingly, DM-2OG exerted a positive effect on pericyte–endothelial cell interaction in the co-culture angiogenesis assay, independent of the diabetic status. Conclusions/interpretation These novel findings support the concept of using DM-2OG supplementation to improve pericyte redox balance and mitochondrial function, while concurrently allowing for enhanced pericyte–endothelial crosstalk. Such effects may help to prevent or slow down vasculopathy in skeletal muscles of people with diabetes

Feasibility and long-term results of focused radioguided parathyroidectomy using a "low" 37 MBq (1 mCi) (99m)Tc-sestamibi protocol

Aim of the present study was to investigate the feasibility and long-term results of focused radioguided parathyroidectomy using a "low" 37 MBq (1 mCi) (99m)Tc-sestamibi dose protocol compared to conventional "high 740 MBq (20 mCi) (99m)Tc-sestamibi dose protocol" in patients with primary hyperparathyroidism (PHPT). The data of focused radioguided surgery obtained in a group of 320 consecutive PHPT patients with high probability of the presence of a solitary parathyroid adenoma (PA) were studied. All patients underwent preoperative imaging work-up of double-tracer (99m)Tc-pertechnetate/(99m)Tc-sestamibi subtraction parathyroid scintigraphy (Sestamibi scintigraphy) and high resolution neck ultrasound (US). In 301/320 patients (96.6%) focused minimally invasive radioguided surgery was successfully performed by administering a "low" 37 MBq (1 mCi) (99m)Tc-sestamibi dose in the operating room 10 minutes before operation. No major intraoperative complications were recorded. Focused radioguided surgery required a mean time of 32 min and a mean hospital stay of 1.2 days. Local anesthesia was applied in 75 patients, 66 of whom (88%) were patients older than 65 years with comorbidities contraindicating general anesthesia. No case of persistent or recurrent PHPT was observed during post-surgical follow-up (range = 18–70 months; mean +/- SD = 15.3 +/- 9.1 months). Radiation exposure dose to the operating surgeon was 1.2 μSi/hour with the "low 37 MBq (1 mCi) (99m)Tc-sestamibi dose", and less than 1.0 μSi/hour for the other operating-room personnel. Focused low dose radioguided parathyroidectomy is a safe and effective means to localize parathyroid adenomas in patients affected by solitary PA thus reducing by 20 fold the radiation exposure dose to the patients and operating room personnel

A Pivotal Role of Lumbar Spinothalamic Cells in the Regulation of Ejaculation via Intraspinal Connections

Introduction.  A population of lumbar spinothalamic cells (LSt cells) has been demonstrated to play a pivotal role in ejaculatory behavior and comprise a critical component of the spinal ejaculation generator. LSt cells are hypothesized to regulate ejaculation via their projections to autonomic and motor neurons in the lumbosacral spinal cord. Aim.  The current study tested the hypothesis that ejaculatory reflexes are dependent on LSt cells via projections within the lumbosacral spinal cord. Methods.  Male rats received intraspinal injections of neurotoxin saporin conjugated to substance P analog, previously shown to selectively lesion LSt cells. Two weeks later, males were anesthetized and spinal cords were transected. Subsequently, males were subjected to ejaculatory reflex paradigms, including stimulation of the dorsal penile nerve (DPN), urethrogenital stimulation or administration of D3 agonist 7‐OH‐DPAT. Electromyographic recordings of the bulbocavernosus muscle (BCM) were analyzed for rhythmic bursting characteristic of the expulsion phase of ejaculation. In addition, a fourth commonly used paradigm for ejaculation and erections in unanesthetized, spinal‐intact male rats was utilized: the ex copula reflex paradigm. Main Outcome Measures.  LSt cell lesions were predicted to prevent rhythmic bursting of BCM following DPN, urethral, or pharmacological stimulation, and emissions in the ex copula paradigm. In contrast, LSt cell lesions were not expected to abolish erectile function as measured in the ex copula paradigm. Results.  LSt cell lesions prevented rhythmic contractions of the BCM induced by any of the ejaculatory reflex paradigms in spinalized rats. However, LSt cell lesions did not affect erectile function nor emissions determined in the ex copula reflex paradigm. Conclusions.  These data demonstrate that LSt cells are essential for ejaculatory, but not erectile reflexes, as previously reported for mating animals. Moreover, LSt cells mediate ejaculation via projections within the spinal cord, presumably to autonomic and motor neurons. Staudt MD, Truitt WA, McKenna KE, de Oliveira CVR, Lehman MN, and Coolen LM. A pivotal role of lumbar spinothalamic cells in the regulation of ejaculation via intraspinal connections. J Sex Med 2012;9:2256–2265.Peer Reviewedhttp://deepblue.lib.umich.edu/bitstream/2027.42/93690/1/j.1743-6109.2011.02574.x.pd

Conditional corticotropin-releasing hormone overexpression in the mouse forebrain enhances rapid eye movement sleep

Impaired sleep and enhanced stress hormone secretion are the hallmarks of stress-related disorders, including major depression. The central neuropeptide, corticotropin-releasing hormone (CRH), is a key hormone that regulates humoral and behavioral adaptation to stress. Its prolonged hypersecretion is believed to play a key role in the development and course of depressive symptoms, and is associated with sleep impairment. To investigate the specific effects of central CRH overexpression on sleep, we used conditional mouse mutants that overexpress CRH in the entire central nervous system (CRH-COE-Nes) or only in the forebrain, including limbic structures (CRH-COE-Cam). Compared with wild-type or control mice during baseline, both homozygous CRH-COE-Nes and -Cam mice showed constantly increased rapid eye movement (REM) sleep, whereas slightly suppressed non-REM sleep was detected only in CRH-COE-Nes mice during the light period. In response to 6-h sleep deprivation, elevated levels of REM sleep also became evident in heterozygous CRH-COE-Nes and -Cam mice during recovery, which was reversed by treatment with a CRH receptor type 1 (CRHR1) antagonist in heterozygous and homozygous CRH-COE-Nes mice. The peripheral stress hormone levels were not elevated at baseline, and even after sleep deprivation they were indistinguishable across genotypes. As the stress axis was not altered, sleep changes, in particular enhanced REM sleep, occurring in these models are most likely induced by the forebrain CRH through the activation of CRHR1. CRH hypersecretion in the forebrain seems to drive REM sleep, supporting the notion that enhanced REM sleep may serve as biomarker for clinical conditions associated with enhanced CRH secretion

Impact of COVID-19 on cardiovascular testing in the United States versus the rest of the world

Objectives: This study sought to quantify and compare the decline in volumes of cardiovascular procedures between the United States and non-US institutions during the early phase of the coronavirus disease-2019 (COVID-19) pandemic. Background: The COVID-19 pandemic has disrupted the care of many non-COVID-19 illnesses. Reductions in diagnostic cardiovascular testing around the world have led to concerns over the implications of reduced testing for cardiovascular disease (CVD) morbidity and mortality. Methods: Data were submitted to the INCAPS-COVID (International Atomic Energy Agency Non-Invasive Cardiology Protocols Study of COVID-19), a multinational registry comprising 909 institutions in 108 countries (including 155 facilities in 40 U.S. states), assessing the impact of the COVID-19 pandemic on volumes of diagnostic cardiovascular procedures. Data were obtained for April 2020 and compared with volumes of baseline procedures from March 2019. We compared laboratory characteristics, practices, and procedure volumes between U.S. and non-U.S. facilities and between U.S. geographic regions and identified factors associated with volume reduction in the United States. Results: Reductions in the volumes of procedures in the United States were similar to those in non-U.S. facilities (68% vs. 63%, respectively; p = 0.237), although U.S. facilities reported greater reductions in invasive coronary angiography (69% vs. 53%, respectively; p < 0.001). Significantly more U.S. facilities reported increased use of telehealth and patient screening measures than non-U.S. facilities, such as temperature checks, symptom screenings, and COVID-19 testing. Reductions in volumes of procedures differed between U.S. regions, with larger declines observed in the Northeast (76%) and Midwest (74%) than in the South (62%) and West (44%). Prevalence of COVID-19, staff redeployments, outpatient centers, and urban centers were associated with greater reductions in volume in U.S. facilities in a multivariable analysis. Conclusions: We observed marked reductions in U.S. cardiovascular testing in the early phase of the pandemic and significant variability between U.S. regions. The association between reductions of volumes and COVID-19 prevalence in the United States highlighted the need for proactive efforts to maintain access to cardiovascular testing in areas most affected by outbreaks of COVID-19 infection