We investigated the effects of chronic oral antihypertensive treatment on functional and structural capillary rarefaction in spontaneously hypertensive rats (SHR). Wistar Kyoto rats (WKY) were used as a normotensive control group. In untreated rats, intravital videomicroscopy showed that functional capillary density was lower in SHR skeletal muscle (WKY 395 +/- 17 and SHR 258 +/- 13 capillaries/mm, P < 0.01) and ear skin (WKY 391 +/- 18 and SHR 210 +/- 15 capillaries/mm, P < 0.01). A linear relationship was seen between skeletal muscle and skin capillary densities (r = 0.654, P < 0.0001). Histologic analysis showed that SHR had a lower capillary-to-fiber ratio in the skeletal muscle (WKY 1.74 +/- 0.08 and SHR 1.40 +/- 0.06, P < 0.01). Capillary volume density-to-fiber volume density ratio in the left ventricle of SHR was also reduced (WKY 0.55 +/- 0.09 and SHR 0.42 +/- 0.09, P < 0.01). The animals were treated with the angiotensin-converting enzyme (ACE) inhibitor enalapril, the angiotensin II type I receptor (AT1) receptor antagonist losartan, the beta-blocker atenolol, or the calcium channel blocker nifedipine, resulting in similar reductions in systolic blood pressure (19.8%, 19.1%, 17.4%, and 18.2%, respectively, P > 0.05). Atenolol did not induce any change in functional capillary density of SHR. Losartan and nifedipine completely reversed functional capillary rarefaction in both muscle and cutaneous tissues, whereas enalapril significantly increased functional capillary density only in the skin. The skeletal muscle capillary-to-fiber ratio was normalized by enalapril, losartan, and nifedipine. Treatments with enalapril or losartan normalized the cardiac structural capillary rarefaction of SHRs, whereas atenolol and nifedipine had no effect. Our results suggest that different pharmacologic classes of antihypertensive drugs with similar effect on blood pressure differ in terms of their effect on the microcirculation.
Meta-chlorophenylpiperazine (m-CPP) is a new illicit drug that has been sold as ecstasy tablets. Easy ambient sonic-spray ionization mass spectrometry (EASI-MS) and X-ray fluorescence spectrometry (XRF) are shown to provide relatively simple and selective screening tools to distinguish m-CPP tablets from tablets containing amphetamines (mainly 3,4-methylenedioxymethamphetamine (MDMA)). EASI-MS detects the active ingredients in their protonated forms: [m-CPP + H](+) of m/z 197, [MDMA + H](+) of m/z 194, and [2MDMA + HCl + H](+) of m/z 423 and other ions from excipients directly on the tablet surface, providing distinct chemical fingerprints. XRF identifies Cl, K, Ca, Fe, and Cu as inorganic ingredients present in the m-CPP tablets. In contrast, higher Cl concentrations and a more diverse set of elements (P, Cl, Ca, Fe, Cu, Zn, Pt, V, Hf, Ti, Pt, and Zr) were found in MDMA tablets. Principal component analysis applied to XRF data arranged samples in three groups: m-CPP tablets (four samples), MDMA tablets (twenty three samples), and tablets with no active ingredients (three samples). The EASI-MS and XRF techniques were also evaluated to quantify m-CPP in ecstasy tablets, with concentrations ranging from 4 to 40 mg of m-CPP per tablets. The m-CPP could only be differentiated from its isomers (o-CPP and for the three isomers p-CPP) by traveling wave ion mobility mass spectrometry and NMR measurements.
Cocaine and crack cocaine are usually seized with a great diversity of adulterants, such as benzocaine, lidocaine, caffeine, and procaine. The forensic identification of cocaine in these drug mixtures is normally performed using colorimetric testing kits, but these tests may suffer from interferences providing false-positive or false-negatives. In this work, we describe the use of thin layer chromatography coupled to easy sonic-spray ambient ionization mass spectrometry (TLC/EASI-MS) for rapid and secure analysis of cocaine and crack cocaine. Fifteen cocaine samples were analyzed, and all of them revealed positive TLC/EASI-MS results for cocaine, but other drugs and adulterants were also detected such as lidocaine, caffeine, benzocaine, lactose, benzoylecgonine, and ecgonidine. False positives and false negatives, as judged by the TLC Rf values, were identified via on-spot characterization by EASI-MS. The TLC/EASI-MS combination seems therefore to provide an appropriate technique for secure forensic investigations of illicit drugs
In general, SARS‐CoV‐2 replication in the host reaches its peak in the first week of infection, decreasing rapidly afterwards, while some level of immunity is build up. Yet, the infection seems to follow a distinctive course in some individuals, reactivating after the apparent resolution of symptoms
1‐3
. We report here the first case to be disclosed of a more vigorous COVID‐19 recurrence with SARS‐CoV‐2 RNA redetection and late antibody response, and also the first to address COVID‐19 recurrence in Brazil.
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