Long period dynamics of viral load and antibodies for SARS-CoV-2 infection: an observational cohort study

OBJECTIVETo investigate the dynamics of viral RNA, IgM, and IgG and their relationships in patients with SARS-CoV-2 pneumonia over an 8-week period. DESIGNRetrospective, observational case series. SETTINGWenzhou Sixth Peoples Hospital PARTICIPANTSThirty-three patients with laboratory confirmed SARS-CoV-2 pneumonia admitted to hospital. Data were collected from January 27 to April 10, 2020. MAIN OUTCOME MEASURESThroat swabs, sputum, stool, and blood samples were collected, and viral load was measured by reverse transcription PCR (RT-PCR). Specific IgM and IgG against spike protein (S), spike protein receptor binding domain (RBD), and nucleocapsid (N) were analyzed. RESULTSAt the early stages of symptom onset, SARS-CoV-2 viral load is higher in throat swabs and sputum, but lower in stool. The median (IQR) time of undetectable viral RNA in throat swab, sputum, and stool was 18.5 (13.25-22) days, 22 (18.5-27.5) days, and 17 (11.5-32) days, respectively. In sputum, 17 patients (51.5%) had undetectable viral RNA within 22 days (short persistence), and 16 (48.5%) had persistent viral RNA more than 22 days (long persistence). Three patients (9.1%) had a detectable relapse of viral RNA in sputum within two weeks of their discharge from the hospital. One patient had persistent viral RNA for 59 days or longer. The median (IQR) seroconversion time of anti-S IgM, anti-RBD IgM, and anti-N IgM was 10.5 (7.75-15.5) days, 14 (9-24) days, and 10 (7-14) days, respectively. The median (IQR) seroconversion time of anti-S IgG, anti-RBD IgG, and anti-N IgG was 10 (7.25-16.5) days, 13 (9-17) days, and 10 (7-14) days, respectively. By week 8 after symptom onset, IgM were negative in many of the previously positive patients, and IgG levels remained less than 50% of the peak levels in more than 20% of the patients. In about 40% of the patients, anti-RBD IgG levels were 4-times higher in convalescence than in acute phase. SARS-CoV-2 RNA coexisted with antibodies for more than 50 days. Anti-RBD IgM and IgG levels, including anti-RBD IgM levels at presentation and peak time, were significantly higher in viral RNA short persistence patients than in long persistence patients. CONCLUSIONThis study adds important new information about the features of viral load and antibody dynamics of SARS-CoV-2. It is clear from these results that the viral RNA persists in sputum and stool specimens for a relatively long time in many patients. Anti-RBD may also serve as a potential protective antibody against SARS-CoV-2 infection, as viral persistence appears to be related to anti-RBD levels. Earlier treatment intervention also appears to be a factor in viral persistence. WHAT IS ALREADY KNOWN ON THIS TOPICThere are several reports about the serum antibodies against SARS-CoV-2. However, most of them evaluate diagnostic accuracy. Only two articles report dynamics of SARS-CoV-2 viral RNA and antibodies with serial samples, but the observation periods are within 30 days. None of the studies investigate the profiles of SARS-CoV-2 viral load and antibodies in a long period. Three reports investigate profiles in respiratory samples, but there are no reports on the dynamics of the viral load in stool samples. WHAT THIS STUDY ADDSIn both sputum and stool, SARS-CoV-2 RNA persists for a long time. The anti-RBD antibodies may involve in the clearance of SARS-CoV-2 infection. After eight weeks from symptom onset, IgM were negative in many of the previously positive patients, and IgG levels remained less than 50% of the peak levels in more than 20% of the patients. In about 40% of the patients, anti-RBD IgG levels increased 4-time higher in convalescence than in acute phase. Long persistence of SARS-CoV-2 viral RNA in sputum and stool presents challenges for management of the infection. The IgM/IgG comb test is better than single IgM test as a supplement diagnostic tool. Anti-RBD may be a protective antibody, and is valuable for development of vaccines.

Hypokalemia and Clinical Implications in Patients with Coronavirus Disease 2019 (COVID-19)

BACKGROUNDSARS-CoV-2 has caused a series of COVID-19 globally. SARS-CoV-2 binds angiotensin I converting enzyme 2 (ACE2) of renin-angiotensin system (RAS) and causes prevalent hypokalemia METHODSThe patients with COVID-19 were classified into severe hypokalemia, hypokalemia, and normokalemia group. The study aimed to determine the relationship between hypokalemia and clinical features, the underlying causes and clinical implications of hypokalemia. RESULTSBy Feb 15, 2020, 175 patients with COVID-19 (92 women and 83 men; median age, 46 [IQR, 34-54] years) were admitted to hospital in Wenzhou, China, consisting 39 severe hypokalemia-, 69 hypokalemia-, and 67 normokalemia patients. Gastrointestinal symptoms were not associated with hypokalemia among 108 hypokalemia patients (P > 0.05). Body temperature, CK, CK-MB, LDH, and CRP were significantly associated with the severity of hypokalemia (P<0.01). 93% of severe and critically ill patients had hypokalemia which was most common among elevated CK, CK-MB, LDH, and CRP. Urine K+ loss was the primary cause of hypokalemia. 1 severe hypokalemia patients was given 3 g/day, adding up to an average of 34 (SD=4) g potassium during hospital stay. The exciting finding was that patients responded well to K+ supplements when they were inclined to recovery. CONCLUSIONSHypokalemia is prevailing in patients with COVID-19. The correction of hypokalemia is challenging because of continuous renal K+ loss resulting from the degradation of ACE2. The end of urine K+ loss indicates a good prognosis and may be a reliable, in-time, and sensitive biomarker directly reflecting the end of adverse effect on RAS system.

SNHG20 knockdown suppresses proliferation, migration and invasion, and promotes apoptosis in non-small cell lung cancer through acting as a miR-154 sponge.

Long noncoding RNAs (LncRNAs) play critical roles in the development and progression of cancers. However, little is known about the function and mechanism of lncRNAs in non-small cell lung cancer (NSCLC). In this study, we investigated the expression and functional role of lncRNA small nucleolar RNA host gene 20 (SNHG20) as well as its underlying mechanism in NSCLC. Our results showed that SNHG20 was significantly up-regulated in NSCLC tissues and cells. High SNHG20 expression was implicated with poor prognosis in NSCLC patients. Moreover, SNHG20 knockdown suppressed proliferation, migration and invasion, and induced apoptosis in NSCLC cells. Furthermore, SNHG20 could function as a competing endogenous RNA (ceRNA) to elevate ZEB2 and RUNX2 expression by sponging miR-154. Rescue assays revealed that miR-154 inhibition could reverse the inhibitory effect of SNHG20 silence on proliferation, migration and invasion in NSCLC cells. More importantly, SNHG20 knockdown suppressed tumor growth in NSCLC in vivo through suppressing miR-154 and elevating ZEB2 and RUNX2 expression. In summary, knockdown of lncRNA SNHG20 suppressed proliferation, migration and invasion, and promotes apoptosis through up-regulating ZEB2 and RUNX2 expression by sponging miR-154 in NSCLC, providing a promising therapeutic target for NSCLC patients.

Diagnostic value of four techniques of detecting the Mycobacterium tuberculosis in bronchoalveolar la-vage fluid in tracheobronchial tuberculosis / 实用医学杂志

Objective To assess the value of four different techniques of detecting the Mycobacterium tuberculosis (MTB) in bronchoalveolar lavage fluid (BALF) in the diagnosis of tracheobronchial tuberculosis. Methods A total of 98 patients diagnosed as tracheobronchial tuberculosis were selected from May 1,2013 to June 30,2016. The clinical data was analyzed retrospectively,and the positive rates of MTB of the 960 cultrue, the direct smears , the modified Ziehl?Neelsen stain method and Xpert MTB/RIF assay were compared. Results The positive rates of the 960 cultrue,the direct smears,the modified Ziehl?Neelsen stain method and Xpert MTB/RIF assay were 20.4%(20/98),15.3%(15/98),70.4%(69/98) and 74.5%(73/98),respectively. Among the four techniques ,the positive rates of the modified Ziehl?Neelsen stain method and Xpert MTB/RIF assay were significantly higher than those of the 960 cultrue and the direct smears(P 0.05). Conclusions The modified Ziehl?Neelsen stain method and Xpert MTB/RIF assay for detecting the MTB in BALF have high clinical value in the diagnosis of tracheobronchial tuberculosis.

A New Unusual Ice-induced Sedimentary Structure: the Silt Mushroom.

Upon channel bars or point bars within the lows of the Yellow River, a new sedimentary structure, named 'silt mushroom', has been observed. The process of their formation is interpreted to be via the ice process. The name, the silt mushroom comes from their figurative form. This is because they look somewhat similar to mushroom's in size and shape; being in the range of 1 to 10 cm in diameter, with the medium 3-5 cm, and on average 10 cm in height, occuring generally in groups, and occasionally in isolation in relatively soft silt. They develop in the transition from winter to spring, and are convincingly related to ice processes. Ice-induced silt mushrooms are best examined in association with the many other newly discovered ice-induced sedimentary structures (over 20 kinds). Clearly, up to now, ice processes have been significantly underestimated. With the substantial discovery of the ice-induced silt mushroom, it opens up new questions. This is because its structure mirrors the same sedimentary structures found in rocks, questioning their genesis, and sedimentary environment analysis. This achievement is significant not only in sedimentology, but also in palaeogeography, palaeoclimate, geological engineering, hydraulics and fluviology.

Efficacy analysis of acyclovir combined with pidotimod in treatment of adult varicella / 中国基层医药

Objective To explore the curative effect of acyclovir combined with pidotimod in treatment of adult varicella.Methods 80 adult patients with varicella in our hospital were randomly divided into two groups.40 cases in group A were intravenously injected acyclovir.40 cases in group B were intravenously injected acyclovir combined with oral pidotimod.The time of herpes blisters drying and completely crusted were observed in two groups.Results The time of herpes blisters drying and completely crusted of B group was shorter than A group.And the differences were statistically significant(P ＜0.01).Conclusion Acyclovir combined with pidotimod in treatment of adult varicella can significantly shorten the healing time,and show better curative effect than single use of acyclovir.

Analysis of clinical features and treatment of patients with severe type A H1N1 flu in Wenzhou / 中华传染病杂志

Objective To investigate the clinical features and effective treatment of patients with severe type A H1N1 flu in Wenzhou. Methods The clinical data of 42 hospitalized patients with severe type A H1N1 flu were analyzed and the clinical features were summarized. Results A total of 42 patients with severe type A H1N1 flu all began with fever and cough. The symptoms of expectoration, pharyngalgia, chilly accounted for 92. 9%, 90. 5% and 42. 9%, respectively. The peripheral leucocyte counts were normal or reduced. C-reactive protein and erythrocyte sedimentation rate levels both increased in 30 patients (71.4%). About 95.2% (40/42) patients had changes of pulmonary imaging. All of the patients were treated with oseltamivir and effective antibiotic drugs as well as symptomatic management. No patients was treated with glucocorticoid. The patients with underlying diseases were given proper treatment. Three cases were treated with antifungal therapy and 3 pregnant patients were timely terminated of pregnancy. Conclusions Severe type A H1N1 flu progresses rapidly and the lower respiratory tract is involved soon after onset. Therefore, the patient should be diagnosed early and treated promptly after presenting fever, which will lead to good prognosis.