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1.
J Pathol Inform ; 13: 100146, 2022.
Artículo en Inglés | MEDLINE | ID: mdl-36268093

RESUMEN

In digital pathology, deep learning has been shown to have a wide range of applications, from cancer grading to segmenting structures like glomeruli. One of the main hurdles for digital pathology to be truly effective is the size of the dataset needed for generalization to address the spectrum of possible morphologies. Small datasets limit classifiers' ability to generalize. Yet, when we move to larger datasets of whole slide images (WSIs) of tissue, these datasets may cause network bottlenecks as each WSI at its original magnification can be upwards of 100 000 by 100 000 pixels, and over a gigabyte in file size. Compounding this problem, high quality pathologist annotations are difficult to obtain, as the volume of necessary annotations to create a classifier that can generalize would be extremely costly in terms of pathologist-hours. In this work, we use Active Learning (AL), a process for iterative interactive training, to create a modified U-net classifier on the region of interest (ROI) scale. We then compare this to Random Learning (RL), where images for addition to the dataset for retraining are randomly selected. Our hypothesis is that AL shows benefits for generating segmentation results versus randomly selecting images to annotate. We show that after 3 iterations, that AL, with an average Dice coefficient of 0.461, outperforms RL, with an average Dice Coefficient of 0.375, by 0.086.

2.
Cureus ; 12(8): e10007, 2020 Aug 25.
Artículo en Inglés | MEDLINE | ID: mdl-32983704

RESUMEN

Xanthogranulomatous cholecystitis (XGC) is a rare inflammatory disease of the gallbladder characterized by severe proliferative fibrosis and the accumulation of lipid-laden macrophages in areas of destructive inflammation. Misdiagnosis is highly usual, and its macroscopic appearance may often be confused with gallbladder carcinoma. Here we discuss the case of a 56-year-old male who presented in the emergency room with fever, chills, and nausea. The routine laboratory investigations were normal except for elevated white blood cell counts. Abdominal ultrasound showed borderline gallbladder wall thickening. However, after CT scan findings, the suspect diagnosis of acute cholecystitis with possible perforation was made and the cholecystectomy was performed. The definitive diagnosis was delayed until the final pathology result came as a surprise, and later confirmed the histologic diagnosis of XGC. We consider this an important case because of the histopathologic finding of fibrotic thickened gallbladder wall with abundant histiocytes and pericholecystic fat stranding along with perforation and extensive inflammatory changes in the right upper quadrant of the abdomen which is highly suggestive and indicative of XGC in comparison to gallbladder carcinoma (GC). All things considered, clinically and grossly XGC presents in a similar fashion as GC; histopathology confirmed the diagnosis of XGC.

3.
Cureus ; 12(6): e8882, 2020 Jun 28.
Artículo en Inglés | MEDLINE | ID: mdl-32742849

RESUMEN

An anal fistula is a condition that has been discussed by various authors without coming to a consensus. The fistula of the anus is a passage that leads from the rectum to the anus. A peri-anal adenocarcinoma is an abnormal growth of cells in the anal rectal area. Establishing the relationship between the two, a lot of information was obtained from the existing literature which has used to come up with solutions to the objective of the study. The review was conducted systematically and included observational retrospective, case studies, and case series to demonstrate the data of valuable research. The articles were searched in PubMed, MEDLINE, and Google scholar using the keywords "chronic perianal fistula", "anal carcinoma", "mucinous adenocarcinoma", and "perianal mucinous adenocarcinoma". Among 50 journal articles, we chose 33 studies describing the clinical sign and symptoms, pathophysiology, etiology, and association between mucinous anal adenocarcinoma and chronic peri-anal fistula. After quality assessment, eight case studies and series were selected, in which seven of them showed the origin of mucinous anal adenocarcinoma from chronic peri-anal fistula. The existence of a long history of fistula-in-ano and the exclusion of any additional carcinoma in the body necessitates the analysis of mucinous adenocarcinoma arising from benign fistula. Likewise, the presence of fistula ought to typically precede that of carcinoma by 10 years, and this is one of the criteria for diagnosis. However, more investigation should be conducted to gain full information about the connection between these two entities.

4.
Cureus ; 12(10): e10772, 2020 Oct 02.
Artículo en Inglés | MEDLINE | ID: mdl-33042650

RESUMEN

Gastrointestinal stromal tumors (GISTs) are the most frequent type of mesenchymal tumors of the gastrointestinal (GI) tract, and most of the time they acquire the mutation of special kinds of genes. GISTs may be familial or inherited and affect several family members of the family or can be sporadic. The risk of GIST is increased in people with mutations in the receptor tyrosine kinase (KIT) and platelet-derived growth factor receptor alpha (PDGFRA) genes. In this report, we present a case of a large GIST with extensive cystic and degenerative change in a 76-year-old female patient with a rare Asp842-His845 deletion mutation detected in PDGFRA exon 18, that required subtotal gastrectomy with en bloc resection.

5.
Cureus ; 12(7): e9158, 2020 Jul 12.
Artículo en Inglés | MEDLINE | ID: mdl-32789094

RESUMEN

Chondrosarcoma is a unique kind of tumor that originates from the cartilage-producing neoplastic mesenchymal cells and appears in both the appendicular and atlantoaxial skeleton. It is the second most prevalent neoplastic bone tumor, with an occurrence of 0.79/100,000/year. The biological presentation of this cancer fluctuates extensively, depending on the grade and anatomical location. Since chondrosarcoma is predominantly resistant to conventional chemo- and radiation therapy, surgical resection remains the sole curative treatment, although at present new treatment modalities are under investigation.

6.
Cureus ; 12(8): e9703, 2020 Aug 12.
Artículo en Inglés | MEDLINE | ID: mdl-32923292

RESUMEN

Desmoplastic trichoepitheliomas (DTEs) are benign cutaneous neoplasms that originate from the hair follicle and exhibit a preference for the facial region. This type of neoplasm is characterized by accelerated growth, with vigorous histologic and immunohistochemical features that may be confused with other skin cancers. Thus, the objective of this study is to establish a definitive diagnosis that can be widely used. This review was systematically carried out and includes case series and studies to establish valuable data that can be used for research. The articles were sought in PubMed, MEDLINE, and Google Scholar using the keywords "desmoplastic trichoepithelioma," "morphea basal cell carcinoma," "microcystic adnexal carcinoma," "syringoma," and "cutaneous breast carcinoma." From a total of 65 journal articles, we chose 42 studies describing the clinical features, etiology, histopathology, and immunohistochemical characteristics of tumors. After quality assessment, 10 studies were selected, representing the differentiating features among the four mentioned cutaneous tumors. The differential diagnosis of DTE also includes other cutaneous and follicular tumors. At present, there is no standardized grading system for trichogenic tumors, although several symptomatic terms have been offered. More recently, immunohistochemistry and histopathological studies support the differentiation between the above-mentioned cutaneous tumors. However, additional research needs to be conducted to obtain complete information regarding the specific distinct traits of the indicated cutaneous tumors.

7.
Cureus ; 12(5): e8207, 2020 May 20.
Artículo en Inglés | MEDLINE | ID: mdl-32577325

RESUMEN

The ongoing pandemic of coronavirus disease 2019 (COVID-19) has affected people from all cultures, religions, gender, and age groups around the world. In the last few months, several studies have been conducted on various aspects of COVID-19. Our goal was to see if the pediatric population is vulnerable to this infection. In this review, we conducted extensive research mainly by using the PubMed database. We used Medical Subject Headings (MeSH) and associated keywords to engage in an extensive search focussing on COVID-19 in the pediatric population. We discovered that most of the studies were from China, and some of them were in the Chinese language. However, English translations of many of the studies were available. For accessing the relevant statistical data, we relied on the World Health Organization (WHO) resources and the official website of the Ontario Government (ontario.ca). Most of the studies showed that the virus has affected the pediatric population. However, we found some differences among these studies regarding the severity of symptoms in children affected by COVID-19. While a few studies stated that the virus has presented with milder symptoms in the pediatric population, some studies have presented data of children who have suffered life-threatening complications due to COVID-19. Although the data is limited, we have been able to conclude from the studies we reviewed that COVID-19 does indeed affect children the same way as any other age group. Moreover, children can act as carriers of the virus and can endanger the lives of other individuals. Besides, neonates and infants can easily acquire the infection from family members without having any exposure to the outside world. Hence, utmost care should be taken while handling this population. More trials and studies should be conducted to analyze the impact of early diagnosis of infection in children and its management.

8.
Cureus ; 12(7): e9211, 2020 Jul 15.
Artículo en Inglés | MEDLINE | ID: mdl-32821563

RESUMEN

Skin cancer is one of the most common cancers in the world and consists of melanoma and non-melanoma skin cancer (NMSC). Basal cell carcinoma (BCC) and squamous cell carcinoma (SCC) are the most common non-melanoma skin cancers. The ideal surgical treatment for BCC is complete removal, and it can be achieved either with safety margins or with micrographic control. The currently accepted treatment for basal cell carcinoma is an elliptical excision with a 4-mm surgical margin of clinically normal skin. However, because of cosmetic and functional constraints on the face, a 4-mm surgical margin is often not feasible. We used PubMed, PubMed Central (PMC), and Google scholar as our main databases to search for the relevant published studies and used "Basal cell carcinoma" and "narrow excision margins" as Medical Subject Headings (MeSH) keywords. Fifteen studies were finalized for the review, which included 3843 lesions. The size of the lesions ranged from 3 to 30 mm, with a mean size of 11.7 mm. Surgical margins varied from 1 to 5 mm. This review was done to evaluate if small, well-defined primary BCCs can be excised using narrow surgical margins. Based on the reviewed literature, we found that for primary well-demarcated BCCs smaller than 2 cm, in the low-risk group, a safety margin of 3 mm gives satisfactory results. In the high-risk group, and for lesions larger than 2 cm, a 4-6 mm margin is suggested for getting clear margins. Mohs micrographic surgery is advocated for more complex and recurrent lesions where the clinical margin is not apparent. However, micrographic surgery is not readily available in many places and requires more training and experience. Therefore, excision with 2 mm margins for clinically well-defined lesions with close follow-up can be followed to preserve the healthy tissue in anatomic constraint lesions and avoid the need for complex reconstructive procedures.

9.
Cureus ; 12(6): e8782, 2020 Jun 23.
Artículo en Inglés | MEDLINE | ID: mdl-32724733

RESUMEN

Valproic acid (VPA) is an anti-epileptic drug (AED) used as a first-choice agent for most forms of epilepsy. It is used in the treatment of manic episodes, bipolar disorder, migraine prevention, and impulse control. Hence it is one of the most commonly prescribed drugs by physicians nowadays. VPA acts by increasing gama amino butyric acid (GABA) levels, and also reduces neuronal activation by blocking voltage-gated sodium, potassium, and calcium channels. VPA has various adverse effects like thrombocytopenia, hyperammonemia, teratogenicity causing spina bifida in newborns when exposed in utero. The focus of this review is to research one such easily overlooked adverse effect of VPA, which is VPA-induced Parkinsonism. We carried out a review of literature and gathered all comprehensive peer-reviewed articles from PubMed. The data for this research were collected ethically and legally after a thorough examination of the literature. Data obtained from the studies have suggested that Parkinsonism is an adverse effect of VPA. Chronic usage of VPA causes Parkinsonism. It occurs equally in males and females, more common in older people usually above the age of 55 years and not dose-dependent. According to the data obtained, all patients who developed Parkinsonism had serum levels in the therapeutic range (50-100 mcg/mL). Thus the chronic intake of maintenance dose of VPA seems to be the leading cause. The symptoms usually improve over a few weeks and fully resolve in a few months after stopping the drug. When the patient's symptoms do not improve, it means VPA has unmasked the underlying potential for developing Parkinson's disease. Such patients benefit from levodopa therapy. However, the mechanism of how VPA causes Parkinsonism remains unknown. Based on the articles reviewed, we hypothesize that VPA's mechanism of neuronal inactivation by blocking membrane channels across the neuronal membrane, primarily when used chronically could be the mechanism by which it causes Parkinsonism. VPA causes down regulation of sodium and potassium channels on neuronal membrane in order to stop the neurons from firing. Thereby a decrease in action potential across the neurons causes a temporary physiological inactivation of the neuron. When multiple neurons are inactivated in the basal ganglia of the brain, the patient develops symptoms of Parkinsonism. As the neurons are only temporarily inactivated physiologically, when the drug is stopped the membrane receptors are reactivated on the neuronal membranes. This leads to neuronal activation and neuronal membrane potential becomes the same as before. The above mechanism clarifies why the symptoms settle down when the medication is stopped.

10.
Cureus ; 12(6): e8460, 2020 Jun 05.
Artículo en Inglés | MEDLINE | ID: mdl-32528783

RESUMEN

Coronavirus disease 2019 (COVID 19) is a catastrophic illness that has significantly altered the world's panoramic view of medicine. As the number of cases around the globe rise, the COVID-19 research writing has been immediately enhanced by professionals internationally. In this review, we focus on the neurological and psychological effects of COVID-19, which can determine both the severity of coronavirus and its related pandemic respectively. While it is critical to distinguish the neurological manifestations from the psychological effects, the latter is becoming more pervasive due to the fast-expanding outbreak. We conducted a systematic review and included observational retrospective, case-series studies, and surveys to establish the largest pool of valuable research. Articles on these approaches were conducted in PubMed, MEDLINE, and Google scholar. Some gray material was also selected because of the recent nature of the disease. Data collected from the studies have proposed that COVID-19 is not unusual in demonstrating the neurological symptoms, as it proved in the past by its sister coronaviruses such as severe acute respiratory syndrome coronavirus-1 (SARS-COV-1) and Middle Eastern respiratory syndrome coronavirus (MERS-COV). Studies have presented that some patients with COVID-19 also showed neurological signs, such as headache, nausea, vomiting, dizziness, loss of taste and smell, and impaired consciousness. However, it necessary to clarify that the invasion of severe acute respiratory syndrome coronavirus-2 (SARS-COV-2) directly or indirectly affects the central nervous system (CNS). Contrarily, the COVID-19 pandemic has affected every single element of life. It has not only changed the individual's health directly but also has significant psychological, economic, and sociological effects. These issues indicate the disease's extraordinary threat, and we must realize that another pandemic will shortly follow it: that of mental and behavioral illness. Thus, the long-lasting psychological implications of this outbreak deserve further investigation side by side.

11.
Eur J Radiol Open ; 7: 100259, 2020.
Artículo en Inglés | MEDLINE | ID: mdl-32944595

RESUMEN

Three-dimensional imaging is a useful tool to evaluate liver structure and surrounding vessels for preoperative planning. In this study, we compared two methods of visualizing vascular maps on computed tomography including maximum intensity projection (MIP) and 3D volume rendered (VR) imaging. We compiled important imaging components of pre-surgical planning, and developed criteria for comparison. The imaging techniques were compared based on colorization, volume quantification, rotation, vessel delineation, small vessel clarity, and segmental liver isolation. MIP had more overall limitations due to reduced differentiation of superimposed structures, motion artifact, and interference from calcifications. We determined that because 3D quantitative volume rendered imaging can provide more detail and perspective than MIP imaging, it may be more useful in preoperative planning for patients with liver malignancy. Advanced 3D imaging is a useful tool that can have profound clinical implications on cancer detection and surgical planning.

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