Prevalence of exercise-induced oxygen desaturation after recovery from SARS-CoV-2 pneumonia and use of lung ultrasound to predict need for pulmonary rehabilitation.

BACKGROUND: Persistence of breathlessness after recovery from SARS-CoV-2 pneumonia is frequent. Recovery from acute respiratory failure (ARF) is usually determined by normalized arterial blood gases (ABGs), but the prevalence of persistent exercise-induced desaturation (EID) and dyspnea is still unknown. METHODS: We investigated the prevalence of EID in 70 patients with normal arterial oxygen at rest after recovery from ARF due to COVID-19 pneumonia. Patients underwent a 6-min walking test (6MWT) before discharge from hospital. We recorded dyspnea score and heart rate during 6MWT. We also investigated the possible role of lung ultrasound (LU) in predicting EID. Patients underwent a LU scan and scores for each explored area were summed to give a total LU score. RESULTS: In 30 patients (43%), oxygen desaturation was >4% during 6MWT. These patients had significantly higher dyspnea and heart rate compared to non-desaturators. LU score >8.5 was significantly able to discriminate patients with EID. CONCLUSION: In SARS-CoV-2 pneumonia, ABGs at discharge cannot predict the persistence of EID, which is frequent. LU may be useful to identify patients at risk who could benefit from a rehabilitation program.

Polyoxyethylene-poly(methacrylic acid-co-methyl methacrylate) compounds for site-specific peroral delivery.

pH-sensitive interpolymer interactions between high molecular weight polyoxyethylene (POE) and poly(methacrylic acid-co-methyl methacrylate) (Eudragit (EUD) L100 or S100) are evidenced and exploited to prepare, from either POE-EUD coevaporates or POE+EUD physical mixtures, both in the 1:1 wt. ratio, compressed matrix tablets, potentially able to deliver the model drug, prednisolone, to sites in the GI tract characterized by specific pHs, such as the jejunum or the ileum. With these devices, drug release is inhibited at pHs lower than the threshold of EUD ionization, whereas at pHs exceeding such a threshold, the matrix undergoes a gradual erosion, which controls the release. A post-compression exposure of tablets to the vapors of appropriate solvents realizes the necessary compaction of matrices, in fact, a high compression force (3 ton) is insufficient, per se, to prevent matrix disintegration in the dissolution medium, whereas such a disintegration is prevented by the treatment with solvent vapors, even with a low compression force (0.3 ton). With the POE+EUD physical mixtures, the exposure to solvent vapors promotes the formation of a layer of POE-EUD complex at the interfaces of the POE and EUD particles in matrix, which inhibits release at pHs lower than that designed for delivery. Both POE and EUD concur to determine the properties of the POE-EUD complex relevant to drug release, indeed, EUD ionization, which elicits matrix erosion and drug release, is favored by the hydrophilic POE. In fact, matrices based on plain EUD exhibit a comparatively low release rate, more suited to an extended delivery to the colon than to a specific delivery to the ileum. Details of the release mechanism are discussed.

Relationships between adipose tissue characteristics of newborn pigs and subsequent performance: I. Characteristics at 8 days of age and growth rate until slaughter.

The genetic influence on body and adipose tissue characteristics of newborn pigs and their correlations to growth rate, BW, body length, backfat thickness and adipocyte size in the outer and inner layers of backfat in 8-d-old Large White piglets were determined. Samples of adipose tissue were obtained by biopsy. Pigs were born to 32 sows mated with the same boar. Heritability and genetic correlations were estimated with dam component of variance; therefore, bias due to common environmental effects cannot be excluded. The heritability estimate for adipocyte volume (.89 +/- .28) was higher than that for backfat thickness at the first and last thoracic vertebrae (.50 +/- .22; .63 +/- .24) and for body weight (.59 +/- .23) at 8 d. Backfat thickness was more closely related genetically and phenotypically to body weight and length than to adipose tissue cellularity. Heritability estimates were .75 +/- .28 for gain from 8 d to weaning and from weaning to 95 d (probably because of common environmental effects) but were .31 +/- .20 for ADG from 95 d to slaughter. Characteristics at 8 d were closely correlated phenotypically with growth rate until weaning. These correlations became lower in the two subsequent periods (to 95 d and to slaughter). Corresponding genetic correlations were nonsignificant.

Relationships between adipose tissue characteristics of newborn pigs and subsequent performance: II. Carcass traits at 95 and 145 kilograms live weight.

Backfat thickness, carcass length, area of M. longissimus and carcass composition were determined for 253 Large White barrows and gilts to examine the genetic influence on the main characteristics of the carcass and the correlation of these traits with body measurements and fat characteristics at 8 d of age. Pigs were born to 32 sows mated to the same boar. At the age of 8 d, weight, body length and backfat thickness and cellularity were measured. Pigs were slaughtered at 95 and 145 kg live weight. Heritability and genetic correlations were estimated with dam component of variance. Higher adiposity of carcasses was noted for barrows than for gilts and for those animals slaughtered at the heavier vs at the lighter weight. High h2 values were observed for carcass length (.89 +/- .29), area of the M. longissimus (.67 +/- .26) and backfat thickness at the gluteus medius (.77 +/- .28). Percentage of commercial cuts also had high heritabilities. Phenotypic and genetic correlations between the characteristics at 8 d and backfat thickness, carcass length and M. longissimus area at slaughter were not statistically significant. However, significant phenotypic correlations were found between cellularity of the outer and inner layers at 8 d and percentage of major cuts (e.g., rp = .27 with total fat cuts); cellularity of the outer layer at 8 d also was correlated genetically with carcass composition (e.g., rg = .50 +/- .19 with total fat cuts). Genetic predisposition toward intensive fat deposition was more clearly predicted by cellularity than by thickness of adipose tissue in newborn pigs.

Relationships between adipose tissue characteristics of newborn pigs and subsequent performance: III. Histological and chemical characteristics of backfat.

Genetic and phenotypic relationships between adipose tissue characteristics of 253 piglets aged 8 d and qualitative characteristics of their backfat at 95 and 145 kg live weight were studied. Heritability of these qualitative aspects was estimated as well. Backfat samples were tested for cellularity, moisture, lipid content and fatty acid composition of the outer and inner layers. Adipose cellularity at birth proved to be correlated with cell volume, moisture and total unsaturated fatty acid, C18:0 and C18:2 contents present in backfat at slaughter. Estimates of heritability calculated for the outer layer of backfat indicated that progress can be made by selecting for water content and fatty acid composition. Neonatal cellularity furnishes a useful indicator not only of the backfat cell size at slaughter but also of the chemical factors important in determining the physical and organoleptic characteristics of porcine fat.