Oral Mucormycosis: An Inevitable Complication of COVID-19

Individuals who have shown recovery from coronavirus disease (COVID-19) are increasingly getting diagnosed with Mucormycosis or "Black fungus." It is a difficult condition to diagnose as it has symptoms that are common among a variety of diseases. Hence, it is important to identify the presenting signs and understand the underlying pathogenesis of COVID-19 associated Mucormycosis. The incidence of these mycotic infections has shown a substantial increase in current times owing to an increase in the prevalence of immunocompromised subjects, human immunodeficiency virus (HIV) infection, and acquired immunodeficiency syndrome (AIDS). Any suspected case of mucormycosis requires rapid diagnosis and management due to its rapid progression as well as the destructive course of infection. This article reviews the taxonomy, pathogenesis, and clinical signs along with laboratory investigations that may play a vital role in the timely diagnosis of this condition as it is mostly fatal.

Reliability of cheiloscopy and dermatoglyphics in hypertension and diabetes. A comparative study

Background

Both dermatoglyphic and cheiloscopic patterns are genetically determined. These patterns are known to be associated with type II diabetes or diabetes mellitus and hypertension which are also considered to have genetic influence due to their familial occurrence. Hence, the aim of this study was to compare reliability of both cheiloscopy and dermatoglyphics with hypertension and type II diabetes.

Materials and Methods

This was a prospective study conducted on 300 study participants. Both cheiloscopic and dermatoglyphic patterns were recorded using validated techniques. Obtained patterns were analyzed and assessed for statistical analysis using the SPSS version 21.0 statistical software. The Chi-square test was used for analyzing the obtained data.

Results

In the present study, no statistical correlation was obtained between either dermatoglyphic or cheiloscopic patterns and type II diabetes or hypertension.

Conclusion

The present study showed that cheiloscopy or dermatoglyphics cannot be used as a predictive tool for assessing a subject's risk of developing type II diabetes or hypertension. These are contradictory findings, thus emphasizing more research in this area so that these noninvasive techniques can be used as predictive tools for developing essential hypertension or type II diabetes.

Evaluation of surface changes of stainless steel miniplates and screws following retrieval from maxillofacial trauma and orthognathic surgery patients: A comparative study

Background

Metal implants have the potential to degrade body fluids. Corrosive degradation has been demonstrated in laboratory tests, both under simulated clinical conditions and by electrochemical methods, as well as in studies of retrieved metal implants. The clinical importance of degradation of metal implants is evidenced by particulate corrosion and wear products in tissue surrounding the implant, which may ultimately lead to bone loss.

Materials and Methods

The present study is to evaluate the surface changes such as corrosion, surface roughness, and microfractures and for the tensile strength of 18 stainless steel miniplates and 18 stainless steel screws which were used as rigid internal fixation in the management of maxillofacial fractures and orthognathic surgeries.

Results

In this study, surface roughness and microfractures were found in all the miniplates and screws that is 100%. Corrosion degradation was found in 12 of 18 plates that is 66.66%.

Conclusion

Our results through scanning electron microscopy and stereo electron microscopy showed surface roughness, microfractures, and corrosion. However, tensile strength was not affected when the plates were in situ. Through our study, we recommend their retrieval after the purposes of rigid fixation have been fulfilled.

Collaborative Regulation of LRG1 by TGF-β1 and PPAR-β/δ Modulates Chronic Pressure Overload-Induced Cardiac Fibrosis

BACKGROUND

Despite its established significance in fibrotic cardiac remodeling, clinical benefits of global inhibition of TGF (transforming growth factor)-β1 signaling remain controversial. LRG1 (leucine-rich-α2 glycoprotein 1) is known to regulate endothelial TGFβ signaling. This study evaluated the role of LRG1 in cardiac fibrosis and its transcriptional regulatory network in cardiac fibroblasts.

METHODS

Pressure overload-induced heart failure was established by transverse aortic constriction. Western blot, quantitative reverse transcription polymerase chain reaction, immunofluorescence, and immunohistochemistry were used to evaluate the expression level and pattern of interested targets or pathology during fibrotic cardiac remodeling. Cardiac function was assessed by pressure-volume loop analysis.

RESULTS

LRG1 expression was significantly suppressed in left ventricle of mice with transverse aortic constriction-induced fibrotic cardiac remodeling (mean difference, -0.00085 [95% CI, -0.0013 to -0.00043]; P=0.005) and of patients with end-stage ischemic-dilated cardiomyopathy (mean difference, 0.13 [95% CI, 0.012-0.25]; P=0.032). More profound cardiac fibrosis (mean difference, -0.014% [95% CI, -0.029% to -0.00012%]; P=0.048 for interstitial fibrosis; mean difference, -1.3 [95% CI, -2.5 to -0.2]; P=0.016 for perivascular fibrosis), worse cardiac dysfunction (mean difference, -2.5 ms [95% CI, -4.5 to -0.4 ms]; P=0.016 for Tau-g; mean difference, 13% [95% CI, 2%-24%]; P=0.016 for ejection fraction), and hyperactive TGFβ signaling in transverse aortic constriction-operated Lrg1-deficient mice (mean difference, -0.27 [95% CI, -0.47 to -0.07]; P<0.001), which could be reversed by cardiac-specific Lrg1 delivery mediated by adeno-associated virus 9. Mechanistically, LRG1 inhibits cardiac fibroblast activation by competing with TGFβ1 for receptor binding, while PPAR (peroxisome proliferator-activated receptor)-β/δ and TGFβ1 collaboratively regulate LRG1 expression via SMRT (silencing mediator for retinoid and thyroid hormone receptor). We further demonstrated functional interactions between LRG1 and PPARβ/δ in cardiac fibroblast activation.

CONCLUSIONS

Our results established a highly complex molecular network involving LRG1, TGFβ1, PPARβ/δ, and SMRT in regulating cardiac fibroblast activation and cardiac fibrosis. Targeting LRG1 or PPARβ/δ represents a promising strategy to control pathological cardiac remodeling in response to chronic pressure overload.

High-flow-velocity and shear-rate imaging by use of color Doppler optical coherence tomography

Color Doppler optical coherence tomography (CDOCT) is capable of precise velocity mapping in turbid media. Previous CDOCT systems based on the short-time Fourier transform have been limited to maximum flow velocities of the order of tens of millimeters per second. We describe a technique, based on interference signal demodulation at multiple frequencies, to extend the physiological relevance of CDOCT by increasing the dynamic range of measurable velocities to hundreds of millimeters per second. The physiologically important parameter of shear rate is also derived from CDOCT measurements. The measured flow-velocity profiles and shear-rate distributions correlate very well with theoretical predictions. The multiple demodulation technique, therefore, may be useful to monitor blood flow in vivo and to identify regions with high and low shear rates.

Three-dimensional reconstruction of blood vessels from in vivo color Doppler optical coherence tomography images

PURPOSE

Current laser treatment for vascular disorders such as port wine stains can have incomplete or unacceptable results. A customized treatment strategy based on knowledge of the patient's blood vessel structure may effect an improved clinical outcome.

PROCEDURE

We tested the feasibility of using color Doppler optical coherence tomography (OCT) and image processing techniques to locate, measure and reconstruct cutaneous blood vessels in rat and hamster skin. OCT is a recent, potentially noninvasive technique for imaging subsurface tissue structures with micrometer scale resolution.

RESULTS

Blood vessels were identified in a series of cross-sectional images, then a three-dimensional reconstruction was made. Parameters that can affect optimum laser treatment parameters, such as average blood vessel depth and luminal diameter, were found from the images.

CONCLUSION

This study shows that color Doppler OCT is a potential tool for improving laser treatment of vascular disorders.

Velocity-estimation accuracy and frame-rate limitations in color Doppler optical coherence tomography

Color Doppler optical coherence tomography (CDOCT) is a recent innovation that allows spatially localized flow-velocity mapping simultaneously with microstructural imaging. We present a theoretical model for velocity-image formation in CDOCT. The proportionality between the heterodyne detector current Doppler power spectrum in CDOCT and the optical source power spectrum is established. We show that stochastic modifications of the Doppler spectrum by fluctuating scatterer distributions in the flow field give rise to unavoidable velocity-estimation inaccuracies as well as to a fundamental trade-off between image-acquisition rate and velocity precision. Novel algorithms that permit high-fidelity depth-resolved measurements of velocities in turbid media are also reported.

High-resolution cross-sectional imaging of the gastrointestinal tract using optical coherence tomography: preliminary results

BACKGROUND

Optical coherence tomography (OCT) is a novel technique for noninvasive cross-sectional imaging with high spatial resolution (10 to 20 microm). OCT is similar to B-mode ultrasound except that it uses infrared light rather than ultrasound. We studied OCT imaging of the gastrointestinal (GI) tract in vitro to analyze the potential of this technique for endoscopic applications.

METHODS

Human gastrointestinal tissues harvested from surgical resection and autopsy specimens were used. Specimens were imaged within 5 hours of resection or snap frozen in liquid nitrogen. After imaging, OCT scan locations were carefully marked using dye microinjections, fixed, and prepared for routine histologic processing. OCT images were then compared and correlated with the histologic sections.

RESULTS

OCT images demonstrated clear delineation of the mucosa and submucosa in most specimens. Furthermore, microscopic structures such as crypts, blood vessels, or esophageal glands in the submucosa and lymphatic nodules were observed.

CONCLUSIONS

The resolution of OCT images of GI wall is sufficient to delineate the microscopic structure of the mucosa and submucosa. Potentially, OCT would allow in vivo imaging at endoscopy of the microstructure of the mucosa and submucosa. This would be particularly useful in the detection and staging of small lesions such as early stage cancers.

In vivo bidirectional color Doppler flow imaging of picoliter blood volumes using optical coherence tomography

We describe a novel optical system for bidirectional color Doppler imaging of flow in biological tissues with micrometer-scale resolution and demonstrate its use for in vivo imaging of blood flow in an animal model. Our technique, color Doppler optical coherence tomography (CDOCT), performs spatially localized optical Doppler velocimetry by use of scanning low-coherence interferometry. CDOCT is an extension of optical coherence tomography (OCT), employing coherent signal-acquisition electronics and joint time-frequency analysis algorithms to perform flow imaging simultaneous with conventional OCT imaging. Cross-sectional maps of blood flow velocity with <50-microm spatial resolution and <0.6-mm/s velocity precision were obtained through intact skin in living hamster subdermal tissue. This technology has several potential medical applications.