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41.
The protection of the stone surfaces of the buildings of the city of Lecce (Apulia, Italy) represents an ancient practice, which has always allowed the conservation of the historical-artistic heritage of the city, which nowadays is an international touristic and cultural destination. The identification of ancient recipes, materials and methodologies for the protection of historical buildings plays an important role in establishing correct protocols in order to ensure the durability of stone surfaces over time. This work presents a historically accurate reconstruction of the materials and conservation technologies used on the facades of the artistic buildings in Lecce. Several historical buildings, both civil and religious, have been selected in order to investigate the treatments applied on their facades and to know the traditions spread in the past in the field of building conservation in the Salento territory. Thanks to non-invasive or micro-destructive techniques (optical microscopy, ATR-FTIR spectroscopy, pyrolysis–gas chromatography–mass spectrometry), the characteristic molecular markers of the materials and the products of degradation have been identified, deepening the knowledge of the mechanisms of deterioration and interaction between the stone material, the surface finish and the surrounding environment. The paper is a valuable tool for the knowledge of ancient traditions and the planning of proper restoration works.  相似文献   
42.
In the last 20 years, gut microbiota in patients with cystic fibrosis (CF) has become an object of interest. It was shown that these patients had gut dysbiosis and this could explain not only the intestinal manifestations of the disease but also part of those involving the respiratory tract. The acquisition of previously unknown information about the importance of some bacteria, i.e., those partially or totally disappeared in the gut of CF patients, in the regulation of the activity and function of the gut and the lung was the base to suggest the use of probiotics in CF patients. The main aim of this paper is to discuss the biological basis for probiotic administration to CF patients and which results could be expected. Literature analysis showed that CF intestinal dysbiosis depends on the same genetic mutations that condition the clinical picture of the diseases and is aggravated by a series of therapeutic interventions, such as dietary modifications, the use of antibiotics, and the administration of antacids. All this translates into a significant worsening of the structure and function of organs, including the lung and intestine, already deeply penalized by the genetic alterations of CF. Probiotics can intervene on dysbiosis, reducing the negative effects derived from it. However, the available data cannot be considered sufficient to indicate that these bacteria are essential elements of CF therapy. Further studies that take into account the still unsolved aspects on how to use probiotics are absolutely necessary.  相似文献   
43.
Hypertension in pregnancy is often associated to placental deficiency. Therefore several physiopathological modifications occur to sustain fetal well-being through protective mechanisms. Here, we used spontaneously hypertensive rat (SHR) and normotensive Wistar-Kyoto (WKY) counterpart to evaluate in late gestation (d 20) modification of placental proteins involved in adaptation to hypertension. Placenta from WKY and SHR was excised for the evaluation of protein changes by Western blot analysis and zymography. In particular, we showed in SHR placentas an increase in angiotensin receptor type 1 and a decrease in angiotensin converting enzyme. Conversely, inducible nitric oxide synthase expression was increased, while constitutive endothelial nitric oxide synthase was similar in both groups. Placentas from SHR showed a reduced protein expression in both peroxisome proliferators-activated receptors-alpha and -gamma. Pro-metalloproteinase-9 activity was not significantly modified, whereas both pro-metalloproteinase-2 and its active form present a higher activity in SHR placentas. Moreover, at the end of pregnancy, cyclooxygenase-2 expression decreased in SHR placentas. These data may provide new insights into the placental adaptive mechanisms that take place during pregnancy in SHR.  相似文献   
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The severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) spike is a trimer of S1/S2 heterodimers with three receptor-binding domains (RBDs) at the S1 subunit for human angiotensin-converting enzyme 2 (hACE2). Due to their small size, nanobodies can recognize protein cavities that are not accessible to conventional antibodies. To isolate high-affinity nanobodies, large libraries with great diversity are highly desirable. Dromedary camels (Camelus dromedarius) are natural reservoirs of coronaviruses like Middle East respiratory syndrome CoV (MERS-CoV) that are transmitted to humans. Here, we built large dromedary camel VHH phage libraries to isolate nanobodies that broadly neutralize SARS-CoV-2 variants. We isolated two VHH nanobodies, NCI-CoV-7A3 (7A3) and NCI-CoV-8A2 (8A2), which have a high affinity for the RBD via targeting nonoverlapping epitopes and show broad neutralization activity against SARS-CoV-2 and its emerging variants of concern. Cryoelectron microscopy (cryo-EM) complex structures revealed that 8A2 binds the RBD in its up mode with a long CDR3 loop directly involved in the ACE2 binding residues and that 7A3 targets a deeply buried region that uniquely extends from the S1 subunit to the apex of the S2 subunit regardless of the conformational state of the RBD. At a dose of ≥5 mg/kg, 7A3 efficiently protected transgenic mice expressing hACE2 from the lethal challenge of variants B.1.351 or B.1.617.2, suggesting its therapeutic use against COVID-19 variants. The dromedary camel VHH phage libraries could be helpful as a unique platform ready for quickly isolating potent nanobodies against future emerging viruses.

Severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) is the etiologic agent of COVID-19 (1, 2) that enters human cells by binding its envelope anchored type I fusion protein (spike) to angiotensin-converting enzyme 2 (ACE2) (3, 4). The SARS-CoV-2 spike is a trimer of S1/S2 heterodimers with three ACE2 receptor-binding domains (RBDs) attached to the distal end of the spike via a hinge region that allows conformational flexibility (4). In the all-down conformation, the RBDs are packed with their long axes contained in a plane perpendicular to the axis of symmetry of the trimer. Transition to the roughly perpendicular up conformation exposes the receptor-binding motif (RBM), located at the distal end of the RBD, which is sterically occluded in the down state. Numerous neutralizing antibodies targeting the spike, particularly its RBD, have been developed to treat COVID-19 using common strategies such as single B cell cloning, animal immunization, and phage display (59). Most vaccines, including those that are messenger RNA based, are designed to induce immunity against the spike or RBD (1012). However, emerging SARS-CoV-2 variants such as D614G, B.1.1.7 (Alpha, United Kingdom), B.1.351 (Beta, South Africa), and P.1 (Gamma, Brazil) have exhibited increased resistance to neutralization by monoclonal antibodies or postvaccination sera elicited by the COVID-19 vaccines (13, 14). Monoclonal antibodies with Emergency Use Authorization for COVID-19 treatment partially (Casirivimab) or completely (Bamlanivimab) failed to inhibit the B.1.351 and P.1 variants. Similarly, these variants were less effectively inhibited by convalescent plasma and sera from individuals vaccinated with a COVID-19 vaccine (BNT162b2) (13). The B.1.617.2 (Delta, India) variant became the prevailing strain in many countries (15). Highly effective and broadly neutralizing antibody therapy is urgently demanded for COVID-19 patients.Due to their small size and unique conformations, camelid VHH single-domain antibodies (also known as nanobodies) can recognize protein cavities that are not accessible to conventional antibodies (16). To isolate high-affinity nanobodies without a need for further affinity maturation, it is highly desirable to construct large nanobody libraries with great diversity. Dromedary camels have been found as potential natural reservoirs of Middle East respiratory syndrome CoV (MERS-CoV) (17). We speculated that dromedary camels would be an ideal source of neutralizing nanobodies against coronaviruses. In the present study, we built large camel VHH single-domain antibody phage libraries with a diversity of over 1011 from six dromedary camels (Camelus dromedarius), three males and three females, with ages ranging from 3 mo to 20 y. We used both the SARS-CoV-2 RBD and the stabilized spike ectodomain trimer protein as baits to conduct phage panning for nanobody screening. Among all the binders, we found NCI-CoV-7A3 (7A3), NCI-CoV-1B5 (1B5), NCI-CoV-8A2 (8A2), and NCI-CoV-2F7 (2F7) to be potent ACE2 blockers. In addition, these dromedary camel nanobodies displayed potent neutralization activity against the B.1.351 and B.1.1.7 variants and the original strain (Wuhan-Hu-1). The cryoelectron microscopy (cryo-EM) structure of the spike trimer protein complex with these VHH nanobodies revealed two distinct nonoverlapping epitopes for neutralizing SARS-CoV-2. In particular, 7A3 recognizes a unique and deeply buried region that extends to the apex of the S2 subunit of the spike. Combined treatment with 7A3 and 8A2 shows more potent protection against various variants in culture and mice infected with the B.1.351 variant. Interestingly, 7A3 alone retains its neutralization activity against the lethal challenge of the B.1.617.2 variant in mice.  相似文献   
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In male Wistar rats, shuttle-box avoidance test (5 daily sessions of 50 min) significantly decreased (P less than 0.001) by 30% ascorbic acid (AsAc) level in hypothalamus (HYP), while it left it unmodified in striatum (ST) and in the remaining brain (RB), as opposed to untested rats; AsAc level in HYP showed a significant (P less than 0.001) trend to recovery 24 hours after the end of the test. No correlation was found between the rate of conditioned avoidance responses (CAR) and AsAc levels in the above brain regions. d-Amphetamine (d-A), given s.c. at the dose of 1.0 mg/kg/day for 5 consecutive days, significantly increased AsAc levels by 26% in HYP (P less than 0.005), by 14% in ST (P less than 0.05), and by 33% in RB (P less than 0.001), as opposed to untreated rats; return of AsAc toward baseline levels was negligible 24 hours after d-A withdrawal. The above d-A treatment schedule significantly increased (P 0.05) the rate of CAR in the shuttle-box test. AsAc levels resulted also significantly higher (P less than 0.001) in HYP (+81%) and in RB (+46%) at the end of the test; the AsAc level increase was negligible in ST. Twenty-four hours later, AsAc levels were still significantly higher in RB, but returned toward baseline level in HYP. Again, no correlation was found between CAR rate and regional brain AsAc levels. These results demonstrate that d-A is able to increase regional brain AsAc levels both in control and in tested rats. Since it is well known that systemic administration of AsAc antagonizes some d-A behavioral effects, it is suggested, as a working hypothesis, that the d-A CNS stimulating effect may cause a recruitment of endogenous AsAc, whose task could be a negative neuromodulatory action on the overall effect of d-A on neuronal activity.  相似文献   
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Transverse myelitis is a rare autoimmune inflammatory disease often secondary to viral infection of the spinal cord; it frequently has vesico-sphynteric complications. Between January 2000 and December 2005 we performed urodynamic examination on 13 consecutive patients (7 females and 6 males) with previous diagnosis of transverse myelitis. Mean age was 54.5 years; transverse myelitis had been diagnosed a mean of 6.3 years earlier; etiology of myelitis was viral infection in 5 cases, autoimmune in 3 cases, insect bite in 1 case, unknown in 4 cases. The neurological sequelae included paraparesis in 3 cases and tetraparesis in 2 cases. Symptoms: dysuria 46%, slow stream 15%, pollakiuria 23%, urgency 30%; urge incontinence 38%, stress incontinence 15%. 3 patients performed 4 clean intermittent catheterisms (CIC), 2 patients 2 CICs. Eight patients had maximum cystometric capacity above 350 mL, the others had a mean capacity of 223 mL. Four patients showed no bladder sensitivity. Voluntary micturitional reflex was observed in 4 patients. Detrusor overactivity was diagnosed in 9 patients, 10 patients had mean residual post-micturition (RPM) of 218 mL, 2 patients showed detrusor-sphincter dyssynergia, 2 patients were found to be obstructed at pressure-flow study. Urodynamic follow-up is indicated in these patients with or without neurological complications (possibility of detrusor overactivity, urinary retention, detrusor-sphincter dyssynergia); the follow-up personalizes the diagnosis and therapy, and prevents complications.  相似文献   
50.
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