The Impact of Regiodefects on the Melt-Memory of Isotactic Polypropylene.

The memory of crystalline phase in the melt of isotactic polypropylene (iPP) in regiodefective samples of iPP characterized by different concentrations regiodefects, constituted by secondary 2,1 propene units, is studied. The self-nucleation (SN) experiments have demonstrated that the presence of 2,1 regiodefects produces a strong memory of the crystalline phase in the melt that persists up to temperatures much higher than the melting temperature. The extension of the heterogeneous melt (domain II) containing self-nuclei increases with increasing the concentration of regiodefects. The higher the concentration of regiodefects the higher the temperature at which the self-nuclei are dissolved and the homogeneous melt is achieved. This demonstrates that a strong memory of the crystalline phase of iPP in the melt exists not only in copolymers with noncrystallizable bulky comonomeric units rejected from the crystals but even when small defects are largely included in the crystals.

Combining Cyclic Units and Unsaturated Pendant Groups by Propene/1,5-Hexadiene Copolymerization Toward Functional Isotactic Polypropylene.

The precise use of a widely available and inexpensive metallocene catalyst enabled the synthesis of isotactic polypropylene copolymers characterized by the copresence of randomly distributed cyclic units in the backbone and unsaturated pendant units employing 1,5-hexadiene as comonomer. Optimization of the polymerization conditions avoided the cross-linking phenomena that negatively affects the material processing and final properties, resulting in good yields of samples featuring high molecular masses and a precisely controlled microstructure. Such polypropylene-based copolymers exhibit a broad spectrum of properties ranging from thermoplastic to surprising elastomeric behavior, with the additional value of being functionalizable by post-polymerization reactions.

Keto-Polyethylenes with Controlled Crystallinity and Materials Properties from Catalytic Ethylene-CO-Norbornene Terpolymerization.

Recent advances in Ni(II) catalyzed, nonalternating catalytic copolymerization of ethylene with carbon monoxide (CO) enable the synthesis of in-chain keto-functionalized polyethylenes (keto-PEs) with high-density polyethylene-like materials properties. Addition of norbornene as a bulky, noncrystallizable comonomer during catalytic polymerization allows tuning of the crystallinity in these keto-PE materials by randomly incorporated norbornene units in the polymer chain, while molecular weights are not adversely affected. Such crystallinity-reduced keto-PEs are characterized as softer materials with better ductility and may therefore be more suited for, e.g., potential film applications.

Crystallization Behavior of Isotactic Propene-Octene Random Copolymers.

The crystallization behavior of random propene-octene isotactic copolymers (iPPC8) prepared with a homogeneous metallocene catalyst has been studied. Samples of iPPC8 with low octene content up to about 7 mol% were isothermally crystallized from the melt at various crystallization temperatures. The samples crystallize in mixtures of the α and γ forms of isotactic polypropylene (iPP). The relative amount of γ form increases with increasing crystallization temperature, and a maximum amount of γ form (fγ(max)) is achieved for each sample. The crystallization behavior of iPPC8 copolymers is compared with the crystallization from the melt of propene-ethylene, propene-butene, propene-pentene, and propene-hexene copolymers. The results show that the behavior of iPPC8 copolymers is completely different from those described in the literature for the other copolymers of iPP. In fact, the maximum amount of γ form achieved in samples of different copolymers of iPP generally increases with increasing comonomer content, while in iPPC8 copolymers the maximum amount of γ form decreases with increasing octene content. The different behaviors are discussed based on the inclusion of co-monomeric units in the crystals of α and γ forms of iPP or their exclusion from the crystals. In iPPC8 copolymers, octene units are excluded from the crystals giving only the interruption effect that shortens the length of regular propene sequences, inducing crystallization of the γ form at low octene concentrations, lower than 2 mol%. At higher octene concentration, the crystallization of the kinetically favored α form prevails.

Melt-Crystallizations of α and γ Forms of Isotactic Polypropylene in Propene-Butene Copolymers.

Random isotactic propene-butene copolymers (iPPC4) of different stereoregularity have been synthesized with three different homogeneous single center metallocene catalysts having different stereoselectivity. All samples crystallize from the polymerization solution in mixtures of α and γ forms, and the relative amount of γ form increases with increasing concentrations of butene and of rr stereodefects. All samples crystallize from the melt in mixtures of α and γ forms and the fraction of γ form increases with decreasing cooling rate. At high cooling rates, the crystallization of the α form is always favored, even for samples that contain high total concentration of defects that should crystallize in the γ form. The results demonstrate that in iPPs containing significant concentrations of defects, such as stereodefects and comonomeric units, the γ form is the thermodynamically stable form of iPP and crystallizes in selective conditions of very slow crystallization, whereas the α form is the kinetically favored form and crystallizes in conditions of fast crystallization.

Structure and Morphology of Crystalline Syndiotactic Polypropylene-Polyethylene Block Copolymers.

A study of the structure and morphology of diblock copolymers composed of crystallizable blocks of polyethylene (PE) and syndiotactic polypropylene (sPP) having different lengths is reported. In both analyzed samples, the PE block crystallizes first by cooling from the melt (at 130 °C) and the sPP block crystallizes after at a lower temperature. Small angle X-ray scattering (SAXS) recorded during cooling showed three correlation peaks at values of the scattering vector, q1 = 0.12 nm-1, q2 = 0.24 nm-1 and q3 = 0.4 nm-1, indicating development of a lamellar morphology, where lamellar domains of PE and sPP alternate, each domain containing stacks of crystalline lamellae of PE or sPP sandwiched by their own amorphous phase of PE or sPP. At temperatures higher than 120 °C, when only PE crystals are formed, the morphology is defined by the formation of stacks of PE lamellae (17 nm thick) alternating with amorphous layers and with a long period of nearly 52 nm. At lower temperatures, when crystals of sPP are also well-formed, the morphology is more complex. A model of the morphology at room temperature is proposed based on the correlation distances determined from the self-correlation functions extracted from the SAXS data. Lamellar domains of PE (41.5 nm thick) and sPP (8.2 nm thick) alternate, each domain containing stacks of crystalline lamellae sandwiched by their own amorphous phase, forming a global morphology having a total lamellar periodicity of 49.7 nm, characterized by alternating amorphous and crystalline layers, where the crystalline layers are alternatively made of stacks of PE lamellae (22 nm thick) and thinner sPP lamellae (only 3.5 nm thick).

Late Worsening of COVID-19 Pneumonia: Successful Treatment with Ruxolitinib and Steroid.

We describe the case of a patient hospitalized for the second time in a month due to delayed worsening of lung lesions in COVID-19 infection without bacterial superinfection. He was treated with hydroxychloroquine, IV dexamethasone and ruxolitinib with rapid improvement of respiratory failure; 1 month after the second discharge, maintaining low-dose oral prednisone, lung consolidations were significantly reduced on control CT. LEARNING POINTS: Modulation of immune over-response in late phases of COVID-19 can influence global outcome.Ruxolitinib and IV steroids can reverse the inflammatory process and lung lesions.

Three-month mortality in permanently bedridden medical non-oncologic patients. The BECLAP study (permanently BEdridden, creatinine CLearance, albumin, previous hospital admissions study).

OBJECTIVE: To predict the 3-months mortality in permanently bedridden medical non-oncologic inpatients. PATIENTS AND METHODS: 2788 consecutive patients admitted in 5 Italian Internal Medicine units from January 2016 through January 2017 were prospectively screened; 644 oncologic patients were excluded; 2144 non-oncologic patients (1021 female) were followed-up for mortality for 6 months. Main outcome was 3-months mortality in permanently bedridden inpatients with at least 2 of: creatinine clearance <35 ml/min; albumin < 2.5 g/dl; at least 2 hospital admissions in the previous 6 months. Advanced dementia and dysphagia were also recorded. RESULTS: Mean age of the 2144 patients was 73.9 (SD, 14.9) years; 374 (17%) were permanently bedridden, 435 (20%) had a creatinine clearance <35 ml/min, 217 (10%) albumin <2,5 g/dl, 112 (5%) at least 2 hospital admissions in the previous 6 months. Seventy-seven (4%) patients were permanently bedridden with at least 2 of the above mentioned items, and 48 of them died within 3 months (62%) (p < 0.001;95% CI 51-73%). Regression coefficients of the variables associated with 3-months mortality in multivariate analysis in 998 patients of unit 1 (training cohort) were used to create a simple score, which was validated in the 1146 patients of the other units (validation cohort) and performed well in predicting the 3-months mortality (https://www.ejcrim.com/beclap/). CONCLUSIONS: Approximately two out of three non-oncologic medical patients permanently bedridden having 2 of the abovementioned items are dead 3 months after index admission; a simple score including bedridden status, creatinine clearance, albumin, dysphagia, age and sex may help discuss management priorities.

Biotechnological innovations for table olives.

The production of table olives is based on a relatively simple flow chart, including debittering and lactic fermentation. Producers' demand for innovation was the background to design and test some innovative and alternative approaches, i.e. the selection of suitable starter cultures (both lactic acid bacteria and yeasts), the production of functional olives inoculated with probiotic strains, the use of bioremediation (i.e. degradation of oleuropein by bacteria or yeasts), as well as the inoculation of functional starter cultures with a strong biopreservative effect. This article reports a brief description of the most important innovations, with a special focus on the role of traditional and innovative starter cultures.

Ultrasound, anthropometry and bioimpedance: a comparison in predicting fat deposition in non-alcoholic fatty liver disease.

PURPOSE: The aim of our study was the evaluation of anthropometric measurements [waist circumference and sagittal abdominal diameter (SAD)] and abdominal bioelectrical impedance analysis (BIA) (ViScan, TANITA) in comparison to several abdominal ultrasonographic (US) measurements to estimate visceral fat deposition and liver steatosis in a population of 105 subjects. METHODS: All 105 patients underwent a complete anthropometric evaluation, blood sample for the determination of total cholesterol, HDL cholesterol, triglycerides, glucose, insulin, high-sensitivity C-reactive protein, BIA and US measurements (peritoneal, pre-peritoneal, peri-renal, para-renal and peri-hepatic fat thickness). RESULTS: All the ultrasonographic markers considered in our study are related to the presence of non-alcoholic fatty liver disease (NAFLD), and so is true for SAD. Comparing ROC curves, peritoneal fat tissue thickness, SAD and ViScan visceral index are significantly better than waist circumference in predicting the presence of NAFLD (AUC 0.79 ± 0.04; 0.81 ± 0.05; 0.82 ± 0.04 vs 0.76 ± 0.05, respectively). CONCLUSIONS: According to our data, various methods may be useful in evaluating NAFLD, but only ViScan visceral index, US peritoneal fat thickness and SAD are better than waist circumference. Among them, SAD is the most promising, due to its small cost and time consumption.

Surgical treatment of multiple symmetric lipomatosis with ultrasound-assisted liposuction.

Multiple symmetric lipomatosis (MSL) is a rare disease of unknown etiology, characterized by the presence of multiple, symmetrical, noncapsulated lipomas, mostly in the neck and upper trunk. To date, there is no effective medical treatment of MSL. Surgical treatment is based on 2 options, namely, lipectomy and/or liposuction. In this retrospective study, we compare traditional lipectomy with ultrasound-assisted liposuction. Our initial experience demonstrates that the ultrasound-assisted liposuction procedure can be applied to patients with MSL, allowing simultaneous treatment of multiple areas in a single session and the removal of a substantial amount of fat, thus improving aesthetic results. If lipomas are circumscribed and isolated, traditional lipectomy is probably to be preferred.

Long-term cardiovascular risk and coronary events in morbidly obese patients treated with laparoscopic gastric banding.

BACKGROUND: Long-term studies reporting the effects of bariatric surgery on cardiovascular risk factors and events are scarce. The aim of this study was to analyze reduction of multiple cardiovascular risk factors and rates of coronary events in morbidly obese patients treated with bariatric surgery and with>10 years of follow-up. METHODS: This was a prospective uncontrolled study with laparoscopic adjustable gastric banding. Cardiovascular risk factors (fasting glucose, total cholesterol, HDL-C, triglycerides, blood pressure) have been previously determined both at surgery and 12-18 months after in 650 patients treated with laparoscopic adjustable gastric banding from 1993 to 1999. Cardiovascular risk status was again determined in 2010, and the rate of coronary events during long-term (>10 years) follow-up was collected. RESULTS: A total of 318 patients (58 men and 260 women) were retrieved. Age at surgery was 38.6 ± 10.4 years. Body mass index was 46.7 ± 7.2 kg/m(2). Follow-up was 12.7 ± 1.5 years. Weight loss was 17.6% ± 15.7% of baseline weight at 12-18 months and 17.1% ± 14.8% at 12.7 years. A significant reduction in blood glucose, total cholesterol, triglycerides, and systolic and diastolic blood pressure was observed at the short-term evaluation and confirmed in the long term. HDL-C was unchanged at 12-18 months and significantly increased at 12.7 years. Five coronary events (1.6%) were recorded during long-term follow-up. The rate of observed events was compared with the rate of events expected according to baseline 10-year probability of myocardial infarction calculated with the Prospective Cardiovascular Munster study (PROCAM) score. Observed rate (1.6%) was slightly lower than the expected rate (2.0%± 4.9%). CONCLUSIONS: Stable weight loss and significant improvement of cardiovascular risk profile were observed in morbidly obese patients 10 years after laparoscopic adjustable gastric banding.

Broken heart in elderly patients: two clinical observations.

Tako-tsubo cardiomyopathy (idiopathic or transient left ventricular apical ballooning syndrome [ABS]) is a reversible condition frequently precipitated by a stressful trigger that clinically mimics an acute ST-elevation myocardial infarction. Characteristically, hypokinesis or akinesis occurs in the mid- and apical segments of the left ventricle in the absence of epicardial coronary lesions. Preserved or hyperdynamic function of the basal myocardial segments results in apical ballooning, assuming the shape of a Japanese pot used to catch octopus (a takotsubo). We report on 2 well over 70 years old women (78 and 82 years) admitted to the emergency room with chest pain. Clinical signs, ECG alterations and high troponin I in both patients imposed urgent diagnostic testing and management. The electrocardiographic findings were consistent with acute myocardial infarction and transthoracic echocardiography showed in both simultaneous apical akinesia and a hyperkinetic basal area with a moderately reduced left ventricular ejection fraction. Coronary angiography, performed on an emergency basis, in both cases revealed minimal luminal irregularities, with no evidence of plaque rupture or thrombus. The wall motion abnormality extended beyond the distribution of any single coronary artery, making it less likely that an occlusive thrombus had spontaneously dissolved or that intermittent vasospasm had occurred. Taken together, these findings were consistent with ABS, and critical observations on coronary angiography indicated the diagnosis by exclusion. The patients were seen in the clinic 4 weeks after discharge. They had had no recurrent chest pain, and had returned to the normal life they had had before the cardiovascular event. A repeat echocardiography showed a normalized estimated ejection fraction in both patients. ABS is a diagnosis of exclusion and its incidence is probably underestimated in elderly patients in whom coronary angiography is not common.

High-protein low-carbohydrate diets: what is the rationale?

Dietary recommendations released by the large majority of international scientific committees and organizations suggest that the diet for the prevention and treatment of the most compelling health problems of our societies (obesity, diabetes, atherosclerosis, cardiovascular diseases and cancer) should be a diet moderately low in caloric content, low in fat content (particularly in saturated fat), poor in total cholesterol and rich in fibre. Despite this uniformity in official recommendations, alternative diets with low carbohydrate and high protein content continue to be extremely popular within consumers and patients. Recently, new studies seem to suggest that high-protein low-carbohydrate diets may have particularly positive effects on reducing body weight and other risk factors for heart disease. Gannon and Nuttall conducted direct comparisons of high-protein low-carbohydrate diets compared with high-carbohydrate low-protein diets in subjects with type 2 diabetes. They found that high-protein low-carbohydrate diets reduced fasting plasma glucose, 24-h glucose area under the curve and haemoglobin A(1c). On the basis of these results, a joint committee of the American Diabetes Association, North American Society for the Study of Obesity and the American Society for Clinical Nutrition suggested that a low-carbohydrate diet may be preferred to a low-fat diet for the induction of weight loss and glycaemic control in subjects with type 2 diabetes. What is the rationale? What mechanisms are involved?

Weight loss and changes in use of antidiabetic medication in obese type 2 diabetics after laparoscopic gastric banding.

BACKGROUND: Interest in bariatric surgery is growing as an effective method for long-term metabolic control in morbidly obese patients with type 2 diabetes. We analyzed the weight loss and changes in use of diabetic medication in obese patients with type 2 diabetes treated with laparoscopic adjustable gastric banding (LAGB). METHODS: From 1993 to 2005, 1791 morbid obese patients underwent LAGB at our institution. Of the 1791 patients, 394 (22%) had type 2 diabetes mellitus at baseline. Of the 394 patients with diabetes, 52 were receiving diabetic medication. The median follow-up period for the drug-treated diabetic patients was 3 years (range .25-9). RESULTS: The drug-treated diabetic patients were older (age 47.6 +/- 7.5 versus 37.5 +/- 10.7 years, P <.001), weighed more (body mass index 49.1 +/- 9.5 versus 45.6 +/- 7.5 kg/m(2), P 0.001), and were more frequently affected by co-morbidities than the nondiabetic patients at surgery. The percentage of excess weight loss 1 year after surgery was less (32.4% +/- 14.1% versus 41.1% +/- 19.9%, P <.01) for the drug-treated diabetic patients than for the nondiabetic patients. This difference was maintained for 5 years of follow-up. A significant decline occurred in the use of both oral diabetic medication and insulin after surgery. Of the 52 patients treated with oral antidiabetic medication at baseline, 33 required oral antidiabetic medication at the end of follow-up. Of the 6 patients who also required insulin at baseline, 2 did so at the end of follow-up. The use of diabetic medication had increased in 4 patients (7.7%), was unchanged in 12 (23.1%), had decreased in 17 (32.7%), and was suspended in 19 (36.5%) of 52 patients. CONCLUSION: The amount of weight loss after LAGB was less in drug-treated diabetic patients than in nondiabetic patients. However, LAGB was associated with a sustained reduction in the use of diabetic medication.

Upper airway size is related to obesity and body fat distribution in women.

The aim of this study is to analyze the relationships between obesity, fat distribution and pharyngeal transversal area in women. Cross-sectional areas of the pharynx at the oro-pharyngeal junction and at the glottis and mean pharyngeal area were measured by acoustic pharyngometry in 145 women (age 42.9 +/- 15.1 years; range 14-82 years). Body weight, waist, hip and neck circumferences, and sagittal abdominal diameter (SAD) were determined. Pharyngeal area at the oro-pharyngeal junction, measured both in orthostatic and in lying position, was negatively related to BMI, waist, hip and SAD. Mean pharyngeal area was negatively related to BMI and to SAD only in orthostatic position. No significant correlations were found between pharyngeal areas at the glottis and any anthropometric measurements. In multiple regression analysis, only SAD retained independent relationship with pharyngeal area at the level of the oro-pharyngeal junction in both the positions and with mean pharyngeal area in the orthostatic position. We demonstrated an inverse association between upper airways size and both adiposity and visceral fat distribution in women.