Polymorph transformation in paracetamol monitored by in-line NIR spectroscopy during a cooling crystallization process.

The reliable in-line monitoring of pharmaceutical processes has been regarded as a key tool toward the full implementation of process analytical technology. In this study, near-infrared (NIR) spectroscopy was examined for use as an in-line monitoring method of the paracetamol cooling crystallization process. The drug powder was dissolved in ethanol-based cosolvent at 60°C and was cooled by 1°C/min for crystallization. NIR spectra acquired by in-line measurement were interpreted by principal component analysis combined with off-line characterizations via X-ray diffraction, optical microscopy, and transmission electron microscopy. The whole crystallization process appeared to take place in three steps. A metastable form II polymorph of paracetamol was formed and transformed into the stable form I polymorph on the way to the growth of pure form I by cooling crystallization. These observations are consistent with a previous focused beam reflectance method-based study (Barthe et al., Cryst Growth Des 8:3316-3322, 2008).

Chronic hepatitis-C infection in COVID-19 patients is associated with in-hospital mortality.

BACKGROUND: There is little evidence about the association of pre-existing hepatitis C infection (HCV) with outcomes in patients with coronavirus disease 2019 (COVID-19). AIM: To assess the prevalence of history of HCV among patients with COVID-19 and to study the relationship of in-hospital mortality in relation with other predictors of poor outcomes in the presence or absence of COVID-19 induced acute liver injury. METHODS: In a retrospective single-center study design, 1193 patients with COVID-19 infection were studied. Patients were then classified into those with and without a history of HCV, 50 (4.1%) and 1157 (95.9%) respectively. RESULTS: Multivariate cox-regression models showed that age, HCV, D-Dimer, and ferritin were the only predictors of in-hospital mortality. Acute liver injury and fibrosis score (Fib-4 score) were not different between both groups. Multivariate cox-regression model for liver profile revealed that aspartate aminotransferase/ alanine aminotransferase ratio, Fib-4 score, and HCV were predictors of in-hospital mortality. After propensity score matching HCV was the only predictor of mortality in the multivariate cox-regression model. A model including HCV was found to add predictive value to clinical and laboratory parameters. CONCLUSION: In patients with COVID-19, history of HCV infection leads to an accentuated severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) virulence, irrespective of baseline comorbidities, admission laboratory variables, or COVID-19-induced liver injury, which may be related to extrahepatic effects of HCV leading to enhanced ACE-2/TMPRSS mechanisms of SARS-CoV-2 viral entry, baseline cytokine-mediated pro-inflammation, and endothelial dysfunction.

Evolution of Laparoscopic Donor Nephrectomy Techniques and Outcomes: A Single-Center Experience with More than 1000 Cases.

BACKGROUND Laparoscopic donor nephrectomy (LDN) has evolved and has been established as a surgical standard of care for kidney transplantation. MATERIAL AND METHODS This study retrospectively reviews 1132 patients who underwent 4 different laparoscopic living-donor nephrectomies: hand-assisted laparoscopic nephrectomy (HALDN), pure laparoscopic donor nephrectomy (PLDN), laparoendoscopic single-site plus 1-port donor nephrectomy (LESSOP-DN), and mini laparoscopic donor nephrectomy (MLDN). RESULTS The mean estimated blood loss (EBL) for the HALDN group was meaningfully higher than those of LESSOP-DN and MLDN (57.5±52.2 mL versus 21.0±30.0 mL versus 18.2±28.7 mL) (P<0.001). The EBL for PLDN (53.3±35.3 mL) was also significantly higher than those of LESSOP-DN and MLDN (P<0.001). Length of stay (LOS) for HALDN was longer than that for LESSOP-DN (4.2±1.2 day versus 4.0±1.4 days, P=0.002). There was 1 intraoperative open conversion in the HALDN group and 2 HALDN surgeries that required postoperative exploratory laparotomy. LESSOP-DN had 3 (0.8%) postoperative incisional hernias. For recipients, the results revealed no significant differences between all 4 groups in terms of estimated glomerular filtration rate (eGFR) and the 1-year graft failure rate. CONCLUSIONS The LESSOP-DN group was associated with a shorter incision length than those of HALDN and PLDN and shorter LOS than that of HALDN. Recipient results showed no meaningful difference regarding laparoscopic donor nephrectomy technique.

Stimulus-frequency otoacoustic emission: measurements in humans and simulations with an active cochlear model.

An efficient method for measuring stimulus-frequency otoacoustic emissions (SFOAEs) was developed incorporating (1) stimulus with swept frequency or level and (2) the digital heterodyne analysis. SFOAEs were measured for 550-1450 Hz and stimulus levels of 32-62 dB sound pressure level in eight normal human adults. The mean level, number of peaks, frequency spacing between peaks, phase change, and energy-weighted group delays of SFOAEs were determined. Salient features of the human SFOAEs were stimulated with an active cochlear model containing spatially low-pass filtered irregularity in the impedance. An objective fitting procedure yielded an optimal set of model parameters where, with decreasing stimulus level, the amount of cochlear amplification and the base amplitude of the irregularity increased while the spatial low-pass cutoff and the slope of the spatial low-pass filter decreased. The characteristics of the human cochlea were inferred with the model. In the model, an SFOAE consisted of a long-delay component originating from irregularity in a traveling-wave peak region and a short-delay component originating from irregularity in regions remote from the peak. The results of this study should be useful both for understanding cochlear function and for developing a clinical method of assessing cochlear status.

Aortic dissection presenting with secondary pulmonary hypertension caused by compression of the pulmonary artery by dissecting hematoma: a case report.

The rupture of an acute dissection of the ascending aorta into the space surrounding the pulmonary artery is an uncommon occurrence. No previous cases of transient pulmonary hypertension caused by a hematoma surrounding the pulmonary artery have been documented in the literature. Herein, we report a case of acute aortic dissection presenting as secondary pulmonary hypertension.

Nonlinear spectro-temporal features based on a cochlear model for automatic speech recognition in a noisy situation.

A nonlinear speech feature extraction algorithm was developed by modeling human cochlear functions, and demonstrated as a noise-robust front-end for speech recognition systems. The algorithm was based on a model of the Organ of Corti in the human cochlea with such features as such as basilar membrane (BM), outer hair cells (OHCs), and inner hair cells (IHCs). Frequency-dependent nonlinear compression and amplification of OHCs were modeled by lateral inhibition to enhance spectral contrasts. In particular, the compression coefficients had frequency dependency based on the psychoacoustic evidence. Spectral subtraction and temporal adaptation were applied in the time-frame domain. With long-term and short-term adaptation characteristics, these factors remove stationary or slowly varying components and amplify the temporal changes such as onset or offset. The proposed features were evaluated with a noisy speech database and showed better performance than the baseline methods such as mel-frequency cepstral coefficients (MFCCs) and RASTA-PLP in unknown noisy conditions.

Post-harvest HPLC determination of chlorfluazuron residues in pears treated with different programs.

The present study was conducted to monitor the level of chlorfluazuron residues in pear samples in order to assess the risk posed by the presence of such residues to the consumer. Chlorfluazuron was sprayed onto pear trees at the recommended dose rate at two different times at 30 and 21 days prior to harvesting in one treatment, at 21 and 14 days prior to harvesting in another treatment, and three times at 30, 21 and 14 days prior to harvesting in a third treatment. Chlorfluazuron residues were extracted with acetonitrile and partitioned into ethyl acetate. The residue determination was performed on an Apollo C(18) column using HPLC with a UV detection of 254 nm following the clean-up of the extract by open column chromatography with Florisil. The versatility of this method was evidenced by its good linearity (>0.995) in the concentration range between 0.2 and 10 microg/mL. The majority of the mean recoveries at two different fortification levels, 0.05 and 0.25 ppm, ranged from 84.9 +/- 3.2 to 94.3 +/- 10.6, and the repeatability (as the relative standard deviation) from three repetitive determinations of recovery was between 3.8 and 11%. The calculated limit of detection (LOD) was 0.008 ppm and the limit of quantitation was 0.03 ppm. Trace amounts of chlorfluazuron were detectable when it was applied onto the pear trees at two or three times prior to harvesting; however, the levels of chlorfluazuron were not quantified. The excellent sensitivity and selectivity of this method allowed for quantitation and identification at low levels with a run time of less than 12 min. Chlorfluazuron can be used safely to protect pears when sprayed two or three times at 14 days prior to harvesting.