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101.
Anshuman Elhence Manas Vaishnav Sagnik Biswas Ashish Chauhan Abhinav Anand Shalimar 《临床与转化肝病杂志(英文版)》2021,9(2):247-255
Within a year of its emergence, coronavirus disease-2019 (COVID-19) has evolved into a pandemic. What has emerged during the past 1 year is that, apart from its potentially fatal respiratory presentation from which the severe acute respiratory syndrome-coronavirus-2 (SARS-CoV-2) derives its name, it presents with a myriad of gastrointestinal (GI) and liver manifestations. Expression of the angiotensin-converting enzyme-2 (ACE-2) receptor throughout the GI tract and liver, which is the receptor for the SARS-CoV-2, may be responsible for the GI and liver manifestations. Besides acting directly via the ACE-2 receptor, the virus triggers a potent immune response, which might have a role in pathogenesis. The virus leads to derangement in liver function tests in close to 50% of the patients. The impact of these derangements in patients with a normal underlying liver seems to be innocuous. Severe clinical presentations include acute decompensation and acute-on-chronic liver failure in a patient with chronic liver disease, leading to high mortality. Evolving data suggests that, contrary to intuition, liver transplant recipients and patients with autoimmune liver disease on immunosuppression do not have increased mortality. The exact mechanism underlying why immunosuppressed patients fare well as compared to other patients remains to be deciphered. With newer variants of COVID-19, which can spread faster than the original strain, the data on hepatic manifestations needs to be updated to keep a step ahead of the virus. 相似文献
102.
Magnetic resonance cholangiopancreatography in obstructive jaundice 总被引:13,自引:0,他引:13
Vaishali MD Agarwal AK Upadhyaya DN Chauhan VS Sharma OP Shukla VK 《Journal of clinical gastroenterology》2004,38(10):887-890
GOALS: To determine the ability of magnetic resonance cholangiopancreatography (MRCP) to diagnose the level and cause of obstruction in patients with obstructive jaundice. BACKGROUND: The limitations of available imaging modalities have led to the increasing use of MRCP, which is a noninvasive and highly accurate technique in evaluating patients with biliary obstruction. STUDY: Thirty patients were included in this study. MRCP was done using a fat suppressed, heavily T2 weighted fast spin echo sequence. The MRCP findings were confirmed on surgical exploration or clinical follow-up. RESULTS: MRCP could correctly identify ductal dilatation and the level of obstruction in all cases, except one. All causes of obstruction, except three, were detected. It failed to detect a common bile duct calculus in a minimally dilated ductal system and misdiagnosed a case of focal chronic pancreatitis as carcinoma head pancreas and a small pancreatic head mass as cholangiocarcinoma. It had a sensitivity of 94.44%, specificity of 81.81%, positive predictive value of 89.47%, and negative predictive value of 90% for the detection of malignant causes. The overall diagnostic accuracy for detection of level and cause of obstruction was 96.3% and 89.65%, respectively. CONCLUSION: The high diagnostic accuracy of MRCP in evaluating patients with obstructive jaundice indicates that it has the potential to become the diagnostic modality of choice in such patients. 相似文献
103.
The evidence for abandoning the amniotic fluid index in favor of the single deepest pocket 总被引:3,自引:0,他引:3
Magann EF Chauhan SP Doherty DA Magann MI Morrison JC 《American journal of perinatology》2007,24(9):549-555
This study assessed whether the amniotic fluid index (AFI) or the single deepest pocket (SDP) is the best technique to estimate amniotic fluid volume. The AFI and SDP were compared to a dye-determined or directly measured amniotic fluid volume. A PUBMED search from 1990 to 2006 was conducted using the search terms "single deepest pocket" or "largest vertical pocket" or "maximum vertical pocket" or "2X1 pocket" AND "amniotic fluid index". One study compared the AFI and SDP to a dye-determined amniotic fluid volume. There were 1219 publications that used the search term SDP-LVP-MVP versus 4378 using AFI. Twenty publications contained both the AFI and SDP, but only six compared the AFI and SDP. Both the AFI and the SDP poorly identified abnormal amniotic fluid volumes, and neither technique was superior to the other. The AFI identifies a significantly greater number of women as having oligohydramnios versus the SDP but without any difference in perinatal outcomes. Compared with SDP, AFI excessively characterizes a greater number of pregnancies as having oligohydramnios leading to more interventions without improvement in perinatal outcome. The AFI should be abandoned and the SDP used to estimate amniotic fluid volume. 相似文献
104.
Barrilleaux PS Magann EF Chauhan SP York BM Philibert L Lewis DF 《The Journal of reproductive medicine》2007,52(4):293-298
OBJECTIVE: To evaluate the prognostic value of an amniotic fluid index (AFI) < or = 5 cm for an adverse perinatal outcome in pregnancies with the syndrome of hemolysis, elevated liver enzymes and low platelets (HELLP syndrome). STUDY DESIGN: A prospective, observational study of patients with the HELLP syndrome. An ultrasound estimate of amniotic fluid volume was obtained on admission. Adverse intrapartum outcomes included amnioinfusion for variable decelerations and/or indicated abdominal/vaginal operative delivery for nonreassuring fetal heart rate changes. Maternal characteristics and perinatal outcome parameters were compared AFI < or = vs. > 5 cm. Statistical analysis was performed using chi2 analysis, Student's t test and receiver-operator characteristic curve (ROC) analysis. RESULTS: Between January 1996 and February 1999, 120 patients were enrolled. Twenty-six (22%) had an AFI < or = 5 cm. This group did not differ from that with AFI > 5 cm regarding the severity of the HELLP syndrome, admission-to-delivery interval (p = 0.354), variable decelerations in labor (p = 0.06), Apgar score of < 7 at 5 minutes (p = 0.361), cesarean delivery for nonreassuring fetal status (p = 1.0) or significant fetal acidosis (pH < 7.0 [p = 0.2101). ROC analysis revealed no AFI measurement between 0 and 16 cm that was useful for identifying the compromised fetus. CONCLUSION: Antepartum/intrapartum performance of AFI in patients with the HELLP syndrome is a poor prognostic test for subsequent fetal compromise. 相似文献
105.
106.
107.
Background
Toxic liver injury from drugs including paracetamol is the main cause of acute liver failure in developed countries. The mechanisms that drive irreversible liver failure are poorly understood; platelets could have an important role in this process given their roles beyond haemostasis, including liver regeneration. Ligation of the platelet receptor CLEC-2 with its cognate ligand podoplanin (PDPN) powerfully activates platelets; we sought to investigate the role of CLEC-2 in the pathogenesis of acute liver failure.Methods
Paracetamol or carbon tetrachloride (CCl4) were used to induce acute liver damage in mice. The role of CLEC-2-mediated platelet activation was investigated in mice with conditional deletions for either the platelet CLEC-2 receptor (PF4creCLEC1bfl/fl) or PDPN (Vav1-iCre+PDPNfl/fl), or with specific function blocking antibodies. Liver necrosis, and the subsequent inflammatory response, was gauged by assessment of hepatic leucocyte infiltration and measurement of liver histological and serum markers.Findings
Initial liver injury after CCl4 and paracetamol administration was similar in both wild-type (WT) and CLEC-2-deficient mice. Abrogating CLEC-2-driven platelet activation accelerated liver healing from both toxic insults: mean serum alanine aminotransferase [ALT] after paracetamol administration was 1264 IU/L (SE 296·5) in WT mice versus 52·00 (5·00) in CLEC-2-deficient mice (n=5–8, p=0·0078); and after CCl4 4451 (886·3) versus 367 (99·35) (n=4–8, p=0·0015). Targeting this pathway therapeutically with a specific PDPN function blocking antibody in WT mice also enhanced liver healing: after CCl4 administration mean ALT in control antibody treated mice was 5482 (SE 785·4) versus 598·8 (102·4) in anti-PDPN antibody treated mice (n=6, p=0·0001), and after paracetamol 2850 (1128) versus 194·5 (61·26) (p=0·0176). In-vitro experiments showed that CLEC-2-deficient platelets interacted with Kupffer cells to enhance production of tumour necrosis factor α (TNFα) and increase accumulation of hepatic neutrophils. Healing was prevented by either blocking TNFα or depleting neutrophils in mice. Upregulation of PDPN on Kupffer cells in human acute liver failure suggests that this pathway is also activated in human beings.Interpretation
Platelets are involved in determining the outcome of the sterile inflammatory response to toxic liver injury. Platelet activation via CLEC-2 in the context of an acute liver injury inhibits TNFα-driven reparative inflammation mediated by neutrophils. The fact that blocking CLEC-2-mediated platelet activation enhances neutrophil-driven liver repair without causing bleeding, suggests that this could be a completely novel treatment for human acute liver failure.Funding
Wellcome Trust. 相似文献108.
109.
Vishram Singh D. Krishna Chaitanya B.K.S. Chauhan I. David Victor Kumar 《Journal of the Anatomical Society of India》2017,66(1):78-81
Introduction
The present review is based on the study of various classifications of pneumatization of temporal bone and their comparison. The air cells are classified based on their location in the temporal bone in a radiograph or based on their interpretation by a radiologist or otolaryngologist with the help of different reference structures.Methods
The analysis of pneumatization in temporal bone is done by reviewing research articles related to pneumatization of temporal bone in pig, sheep, macaque and humans published in Pubmed, Sciencedirect, Scopus, and Medline, Indexed journals.Results and discussion
According to classical classification the temporal bone is divided into five regions viz., middle ear, squamomastoid(mastoid), perilabyrinthine, petrous apex and accessory. The cells are named accordingly and they are further classified into various grades by the degree of pneumatization and density of cells present in the respective regionsMost recent work which has been cited in various articles, is done by Han et al. [19] In this pneumatization is classified based on the visualization of various reference structures such as, sigmoid sinus, labyrinth, and internal carotid artery. The lack of consensus among surgeons and otolaryngologists regarding the classification of the pneumatization of temporal bone may be a cause of failure in a few otologic surgeries such as 10 mastoidectomies etc and postoperative care of skull base surgeries. 相似文献110.