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1.
Artículo en Inglés | MEDLINE | ID: mdl-37551099

RESUMEN

This report describes the case of a 46-year-old non-smoker housewife. She presented to our attention having a diagnosis of "difficult asthma" from another center in the previous two years. She had no allergies and had not been exposed to an excessive amount of noxious stimuli. Her chronic respiratory symptoms (dyspnea on exertion with wheezing) remained uncontrolled despite maximal anti-asthmatic inhaled therapy. An HRCT scan was performed to further investigate other pulmonary diseases that mimic asthma. It revealed a pedunculated endotracheal lesion with regular borders that obstructed 90% of the tracheal lumen. The lesion was removed via rigid bronchoscopy with laser endobronchial; histological examination revealed the presence of atypical carcinoid. Atypical carcinoids are a rare subtype of neuroendocrine lung tumor that accounts for 2% of all thoracic malignancies. They frequently arise from the central airways and cause obstructive symptoms such as coughing, wheezing, chest pain, or recurrent obstructing pneumonia, which is caused by central airway obstruction. Clinical onset is gradual and characterized by non-specific symptoms, which frequently result in misdiagnosis. As a result, in a young patient with progressive dyspnea, chronic cough, and wheezing that is not responding to anti-asthmatic treatment, second-level investigations are required and may lead to a definite diagnosis, allowing the appropriate course of treatment to begin.

2.
J Clin Med ; 11(14)2022 Jul 13.
Artículo en Inglés | MEDLINE | ID: mdl-35887810

RESUMEN

SARS-CoV-2 may lead to a large spectrum of respiratory manifestations, including pulmonary sequelae. We conducted a single-center longitudinal study of survivors from severe COVID-19 cases who underwent a chest CT during hospitalization (CTH). Three months after being discharged, these patients were evaluated by a clinical examination, pulmonary function tests and a chest-CT scan (CTFU). Sixty-two patients were enrolled. At follow-up, 27% complained of exertional dyspnoea and 12% of cough. Dyspnoeic patients had a lower forced expiratory flow (FEF)25-75 (p = 0.015), while a CT scan (p = 0.016 showed that patients with cough had a higher extent of bronchiectasis. Lung volumes and diffusion of carbon monoxide (DLCO) at follow-up were lower in patients who had been invasively ventilated, which correlated inversely with the length of hospitalization and ground-glass extension at CTH. At follow-up, 14.5% of patients had a complete radiological resolution, while 85.5% presented persistence of ground-glass opacities, and 46.7% showed fibrotic-like alterations. Residual ground-glass at CTFU was related to the length of hospitalization (r = 0.48; p = 0.0002) and to the need for mechanical ventilation or high flow oxygen (p = 0.01) during the acute phase. In conclusion, although patients at three months from discharge showed functional impairment and radiological abnormalities, which correlated with a prolonged hospital stay and need for mechanical ventilation, the persistence of respiratory symptoms was related not to parenchymal but rather to airway sequelae.

3.
J Clin Med ; 10(21)2021 Oct 21.
Artículo en Inglés | MEDLINE | ID: mdl-34768352

RESUMEN

Pneumothorax (PNX) and pneumomediastinum (PNM) are potential complications of COVID-19, but their influence on patients' outcomes remains unclear. The aim of the study was to assess incidence, risk factors, and outcomes of severe COVID-19 complicated with PNX/PNM. METHODS: A retrospective multicenter case-control analysis was conducted in COVID-19 patients admitted for respiratory failure in intermediate care units of the Treviso area, Italy, from March 2020 to April 2021. Clinical characteristics and outcomes of patients with and without PNX/PNM were compared. RESULTS: Among 1213 patients, PNX and/or PNM incidence was 4.5%. Among these, 42% had PNX and PNM, 33.5% only PNX, and 24.5% only PNM. COVID-19 patients with PNX/PNM showed higher in-hospital (p = 0.02) and 90-days mortality (p = 0.048), and longer hospitalization length (p = 0.002) than COVID-19 patients without PNX/PNM. At PNX/PNM occurrence, one-third of subjects was not mechanically ventilated, and the respiratory support was similar to the control group. PNX/PNM occurrence was associated with longer symptom length before hospital admission (p = 0.005) and lower levels of blood lymphocytes (p = 0.017). CONCLUSION: PNX/PNM are complications of COVID-19 associated with a worse prognosis in terms of mortality and length of hospitalization. Although they are more frequent in ventilated patients, they can occur in non-ventilated, suggesting that mechanisms other than barotrauma might contribute to their presentation.

4.
Environ Technol ; : 1-9, 2021 Jul 18.
Artículo en Inglés | MEDLINE | ID: mdl-34223801

RESUMEN

The effects of the temporary increase of organic loading rate (OLR) combined with the simultaneous decrease of hydraulic retention time (HRT) on the stability of a pilot scale dry anaerobic digester were investigated. The separately collected organic fraction of municipal solid waste in mesophilic conditions (T = 40°C) was treated. The objective of this study was to verify whether it is possible to feed the digester for short periods, about three consecutive weeks, with higher OLRs and lower HRTs than those considered optimal without generating process failure or long-term instability. Starting from stable operation at a daily OLR of 10.0 kg of total volatile solids (TVS) for digester volume and an HRT of 23 d, the reactor was fed with an OLR of 10.8, 11.7 and 12.5 kg TVS m-3 d-1 corresponding to an HRT of 21, 19 and 18 d, respectively. It was observed that after using an OLR of 10.8 and 11.7 kg TVS m-3 d-1 for 3 weeks with satisfying results, it was possible to restore stable operating conditions at an OLR of 10.0 kg TVS m-3 d-1 in a short time. Otherwise, after using an OLR of 12.5 kg TVS m-3 d-1 the anaerobic digestion was deeply unbalanced and quickly failed. In this latter case, however, it was possible to fully recover and restore the stable conditions of the process within two months.

5.
BMC Pulm Med ; 16(1): 157, 2016 11 22.
Artículo en Inglés | MEDLINE | ID: mdl-27876029

RESUMEN

BACKGROUND: Although a number of studies have suggested that the use of Telemonitoring (TM) in patients with Chronic Obstructive Pulmonary Disease (COPD) can be useful and efficacious, its real utility in detecting Acute Exacerbation (AE) signaling the need for prompt treatment is not entirely clear. The current study aimed to investigate the benefits of a TM system in managing AE in advanced-stage COPD patients to improve their Health-Related Quality of Life (HRQL) and to reduce utilization of healthcare services. METHODS: A 12-month Randomised Controlled Trial (RCT) was conducted in the Veneto region (Italy). Adult patients diagnosed with Class III-IV COPD in accordance with the Global Initiative for Chronic Obstructive Lung Disease (GOLD) classification were recruited and provided a TM system to alert the clinical staff via a trained operator whenever variations in respiratory parameters fell beyond the individual's normal range. The study's primary endpoint was HRQL, measured by the Italian version of the two Short Form 36-item Health Survey (SF36v2). Its secondary endpoints were: scores on the Hospital Anxiety and Depression Scale (HADS); the number and duration of hospitalizations; the number of readmissions; the number of appointments with a pulmonary specialist; the number of visits to the emergency department; and the number of deaths. RESULTS: Three hundred thirty-four patients were enrolled and randomized into two groups for a 1 year period. At its conclusion, changes in the SF36 Physical and Mental Component Summary scores did not significantly differ between the TM and control groups [(-2.07 (8.98) vs -1.91 (7.75); p = 0.889 and -1.08 (11.30) vs -1.92 (10.92); p = 0.5754, respectively]. Variations in HADS were not significantly different between the two groups [0.85 (3.68) vs 0.62 (3.6); p = 0.65 and 0.50 (4.3) vs 0.72 (4.5); p = 0.71]. The hospitalization rate for AECOPD and/or for any cause was not significantly different in the two groups [IRR = 0.89 (95% CI 0.79-1,04); p = 0.16 and IRR = 0.91 (95% CI 0,75 - 1.04); p = 0.16, respectively]. The readmission rate for AECOPD and/or any cause was, however, significantly lower in the TM group with respect to the control one [IRR = 0.43 (95% CI 0.19-0.98); p = 0.01 and 0.46 (95% CI 0.24-0.89); p = 0.01, respectively]. CONCLUSION: Study results showed that in areas where medical services are well established, TM does not significantly improve HRQL in patients with COPD who develop AE. Although not effective in reducing hospitalizations, TM can nevertheless facilitate continuity of care during hospital-to-home transition by reducing the need for early readmission. TRIAL REGISTRATION: Retrospectively registered on January 2012, ClinicalTrials.gov Identifier: NCT01513980 .


Asunto(s)
Servicios de Atención de Salud a Domicilio , Monitoreo Fisiológico , Admisión del Paciente/estadística & datos numéricos , Enfermedad Pulmonar Obstructiva Crónica/fisiopatología , Calidad de Vida , Telemedicina , Anciano , Anciano de 80 o más Años , Progresión de la Enfermedad , Femenino , Humanos , Italia , Masculino , Estudios Retrospectivos , Índice de Severidad de la Enfermedad
6.
Org Biomol Chem ; 8(15): 3444-50, 2010 Aug 07.
Artículo en Inglés | MEDLINE | ID: mdl-20517566

RESUMEN

Allylindium dichloride is an effective reagent for carrying out photolytically initiated radical allylation reactions, as also proved by EPR experiments. In the presence of suitable azides that can give rise to electrophilic radicals, a homolytic chain reaction occurs with formation of allylated compounds. With delta-azido esters and chlorides generation of primary indiumaminyl radicals is followed by a very efficient 1,5-H shift process that gives rise to electrophilic carbon-centred radicals, whose subsequent allylation by the starting indium reagent, followed by aqueous workup, eventually affords allylated nitrogen heterocycles in good yields. Some comparative theoretical calculations accounted for the observation that analogous reactions with an organoallyltin reagent did not work at all. The results show that the reaction with allylindium dichloride seems strongly favoured by both a lower BDE of the allyl-metal bond and a considerably faster, exothermic 1,5-H migration step.

8.
J Org Chem ; 73(12): 4721-4, 2008 Jun 20.
Artículo en Inglés | MEDLINE | ID: mdl-18471016

RESUMEN

The radical reaction of tributyltin hydride with o-iodo- N-methylanilides derived from alpha-azido acids provides an excellent access to alpha-(aminocarbonyl)iminyl radicals through 1,5-hydrogen transfer reaction of initially formed aryl radicals followed by beta-elimination of dinitrogen from ensuing alpha-azido-alpha-(aminocarbonyl)alkyl radicals. The outcoming iminyls display a peculiar tendency to form corresponding nitriles by beta-elimination of aminocarbonyl radicals.

9.
Org Lett ; 10(6): 1127-30, 2008 Mar 20.
Artículo en Inglés | MEDLINE | ID: mdl-18278931

RESUMEN

Homolytic substitution at the sulfur atom of beta-(phenylsulfanyl)vinyl radicals, obtained by radical reaction of benzenethiol with easily accessible alkyl 4-pentynyl sulfides, is a mild, effective, tin-free route for the generation of all types of alkyl radicals. This protocol can be employed in reductive defunctionalizations as well as cyclizations onto both electron-rich and electron-poor C-C double bonds.

10.
J Org Chem ; 71(15): 5822-5, 2006 Jul 21.
Artículo en Inglés | MEDLINE | ID: mdl-16839176

RESUMEN

Aromatic azides are inert toward triethylsilane under thermal conditions in the presence of a radical initiator, but in the presence of additional catalytic amounts of tert-dodecanethiol, they afford anilinosilanes and thence the corresponding anilines in virtually quantitative yields.

11.
Org Lett ; 8(12): 2499-502, 2006 Jun 08.
Artículo en Inglés | MEDLINE | ID: mdl-16737298

RESUMEN

Organic azides are easily reduced to the corresponding amines by reaction with dichloroindium hydride under very mild conditions and in a highly chemoselective fashion. Gamma-azidonitriles give rise to outstanding five-membered cyclizations affording pyrrolidin-2-imines. A rationalization of the overall experimental data cannot exclude the occurrence of competitive radical and nonradical pathways, but certain results are, however, soundly consistent with the intermediacy of indium-bound nitrogen-centered radicals. [reaction: see text]

12.
J Org Chem ; 71(8): 3192-7, 2006 Apr 14.
Artículo en Inglés | MEDLINE | ID: mdl-16599618

RESUMEN

The radical reaction of benzenethiol with S-4-pentynyl carbamothioates provides a valuable protocol for the tin-free generation of carbamoyl radicals, which arise from intramolecular substitution at sulfur by the initial sulfanylvinyl radicals. This procedure can be usefully employed to achieve N-benzylcarbamoyl radical 5-exo and 4-exo cyclizations leading, respectively, to pyrrolidinones and azetidinones, although, for the latter, it seems of lesser utility. Novel evidence is presented that N-tosyl-substituted carbamoyl radicals display a peculiar tendency to yield the corresponding isocyanate by beta-elimination of the tosyl radical.

13.
J Org Chem ; 71(1): 434-7, 2006 Jan 06.
Artículo en Inglés | MEDLINE | ID: mdl-16388679

RESUMEN

[reaction: see text] Aromatic azides are inert toward tributylgermanium hydride under thermal conditions in the absence and in the presence of a radical initiator but in the presence of catalytic amounts of benzenethiol undergo fast reaction, yielding reduced anilines and 2-germylated derivatives in high overall yields.

14.
J Org Chem ; 70(8): 3046-53, 2005 Apr 15.
Artículo en Inglés | MEDLINE | ID: mdl-15822963

RESUMEN

Thermal reaction of various alpha-azido esters with Bu(3)SnH in refluxing benzene results in smooth production of 3-(tributylstannyl)-1-triazene adducts affording cyclized 1,2,3-triazol-4-ones in preference to reduced amines and thence provides a new useful method for the preparation of these triazole derivatives. In the presence of AIBN the occurrence of triazene products still remains important or even exclusive and, consequently, generation of the expected stannylaminyl radicals is seriously limited. With 2-azidomalonates and alpha-azido-beta-keto esters stannyltriazenes can similarly occur in the absence of the radical initiator, but in the latter cases the ensuing triazenes undergo preferential cyclization onto the ketone moiety to give reactive hydroxytriazolines. Contrary to alpha-azido esters, in the presence of AIBN alpha-azido-beta-keto esters as well as azidomalonates give rise only to the usual stannylaminyl radicals. A possible explanation for the different behavior of the mono- and dicarbonyl azides in the presence of AIBN is put forward.

16.
Org Lett ; 6(3): 417-20, 2004 Feb 05.
Artículo en Inglés | MEDLINE | ID: mdl-14748607

RESUMEN

[reaction: see text] Stannylaminyl radicals derived from radical reactions of Bu(3)SnH with azidoalkylmalononitriles exhibit highly efficient 5- and 6-exo cyclization onto either nitrile group to give aminoiminyl radicals that in turn are reduced to amidines or undergo successive 5-exo cyclization onto an internal alkene.

17.
J Org Chem ; 68(9): 3454-64, 2003 May 02.
Artículo en Inglés | MEDLINE | ID: mdl-12713346

RESUMEN

Aryl radicals react with 2-(2-phenylethynyl)phenyl isothiocyanate through a novel radical cascade reaction entailing formation of alpha-(arylsulfanyl)imidoyl radicals and affording a new class of compounds, i.e. thiochromeno[2,3-b]indoles. These derivatives are formed as mixtures of substituted analogues arising from competitive [4 + 2] and [4 + 1] radical annulations. The isomer ratio is strongly dependent on the aryl substituent and is correlated to its capability to delocalize spin density. The presence of a methylsulfanyl group in the ortho-position of the initial aryl radical results in complete regioselectivity and better yields, as the consequence of both strong spin-delocalization effect, which promotes exclusive [4 + 1] annulation, and good radical leaving-group ability, which facilitates aromatization of the final cyclohexadienyl radical. Theoretical calculations support the hypothesis of competitive, independent [4 + 2] and [4 + 1] annulation pathways. They also suggest that rearrangement onto the sulfur atom of the [4 + 1] intermediate does not occur via a sulfuranyl radical but rather through either a transition state or a sulfur-centered (thioamidyl) radical; the latter is possibly the preferred route in the presence of an o-methylsulfanyl moiety that can act as a leaving group in the final ipso-cyclization process.

18.
Org Lett ; 4(18): 3079-81, 2002 Sep 05.
Artículo en Inglés | MEDLINE | ID: mdl-12201721

RESUMEN

[reaction: see text] Aryl- and alkyl-derived azidoacyl radicals, generated from thiolesters by intramolecular homolytic substitution at the sulfur, can undergo five- and six-membered cyclization onto the azido moiety to give cyclized lactams.


Asunto(s)
Lactamas/síntesis química , Acilación , Azidas/química , Ciclización , Radicales Libres/química , Sulfuros/química
19.
J Org Chem ; 62(24): 8394-8399, 1997 Nov 28.
Artículo en Inglés | MEDLINE | ID: mdl-11671977

RESUMEN

A novel cascade radical reaction is described involving aryl isothiocyanates and 2-cyanoaryl radicals. The mechanism entails the formation of an alpha-(arylthio)imidoyl radical, a 5-exo-dig cyclization onto a cyano group, and a final 6-membered ring closure of an iminyl radical. The competitive 5-membered spiro-cyclization of the iminyl, leading to an isomeric product, was only observed in the case of a disubstituted aryl isothiocyanate. The whole process involves a rare example of [3 + 2] radical annulation and allows the one-pot synthesis of tetracondensed nitrogen heterocycles in good yields.

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