Prothrombin Complex Concentrate vs Conservative Management in ICH Associated With Direct Oral Anticoagulants

Importance

Intracerebral hemorrhage (ICH) associated with direct oral anticoagulant (DOAC) use carries extremely high morbidity and mortality. The clinical effectiveness of hemostatic therapy is unclear.

Objective

To compare the clinical and radiological outcomes of DOAC-associated ICH treated with prothrombin complex concentrate (PCC) vs conservative management.

Design, Setting, and Participants

In this population-based, propensity score-weighted retrospective cohort study, patients who developed DOAC-associated ICH from January 1, 2016, to December 31, 2021, in Hong Kong were identified. The outcomes of patients who received 25 to 50 IU/kg PCC with those who received no hemostatic agents were compared. Data were analyzed from May 1, 2022, to June 30, 2023.

Main Outcomes and Measures

The primary outcome was modified Rankin scale of 0 to 3 or returning to baseline functional status at 3 months. Secondary outcomes were mortality at 90 days, in-hospital mortality, and hematoma expansion. Weighted logistic regression was performed to evaluate the association of PCC with study outcomes. In unweighted logistic regression models, factors associated with good neurological outcome and hematoma expansion in DOAC-associated ICH were identified.

Results

A total of 232 patients with DOAC-associated ICH, with a mean (SD) age of 77.2 (9.3) years and 101 (44%) female patients, were included. Among these, 116 (50%) received conservative treatment and 102 (44%) received PCC. Overall, 74 patients (31%) patients had good neurological recovery and 92 (39%) died within 90 days. Median (IQR) baseline hematoma volume was 21.7 mL (3.6-66.1 mL). Compared with conservative management, PCC was not associated with improved neurological recovery (adjusted odds ratio [aOR], 0.62; 95% CI, 0.33-1.16; P = .14), mortality at 90 days (aOR, 1.03; 95% CI, 0.70-1.53; P = .88), in-hospital mortality (aOR, 1.11; 95% CI, 0.69-1.79; P = .66), or reduced hematoma expansion (aOR, 0.94; 95% CI, 0.38-2.31; P = .90). Higher baseline hematoma volume, lower Glasgow coma scale, and intraventricular hemorrhage were associated with lower odds of good neurological outcome but not hematoma expansion.

Conclusions and Relevance

In this cohort study, Chinese patients with DOAC-associated ICH had large baseline hematoma volumes and high rates of mortality and functional disability. PCC treatment was not associated with improved functional outcome, hematoma expansion, or mortality. Further studies on novel hemostatic agents as well as neurosurgical and adjunctive medical therapies are needed to identify the best management algorithm for DOAC-associated ICH.

A WC/WO star exploding within an expanding carbon-oxygen-neon nebula

The final fate of massive stars, and the nature of the compact remnants they leave behind (black holes and neutron stars), are open questions in astrophysics. Many massive stars are stripped of their outer hydrogen envelopes as they evolve. Such Wolf-Rayet stars¹ emit strong and rapidly expanding winds with speeds greater than 1,000 kilometres per second. A fraction of this population is also helium-depleted, with spectra dominated by highly ionized emission lines of carbon and oxygen (types WC/WO). Evidence indicates that the most commonly observed supernova explosions that lack hydrogen and helium (types Ib/Ic) cannot result from massive WC/WO stars^2,3, leading some to suggest that most such stars collapse directly into black holes without a visible supernova explosion⁴. Here we report observations of SN 2019hgp, beginning about a day after the explosion. Its short rise time and rapid decline place it among an emerging population of rapidly evolving transients^5-8. Spectroscopy reveals a rich set of emission lines indicating that the explosion occurred within a nebula composed of carbon, oxygen and neon. Narrow absorption features show that this material is expanding at high velocities (greater than 1,500 kilometres per second), requiring a compact progenitor. Our observations are consistent with an explosion of a massive WC/WO star, and suggest that massive Wolf-Rayet stars may be the progenitors of some rapidly evolving transients.

SIFTING FOR SAPPHIRES: SYSTEMATIC SELECTION OF TIDAL DISRUPTION EVENTS IN iPTF

We present results from a systematic selection of tidal disruption events (TDEs) in a wide-area (4800 deg²), g + R band, Intermediate Palomar Transient Factory (iPTF) experiment. Our selection targets typical optically-selected TDEs: bright (>60% flux increase) and blue transients residing in the center of red galaxies. Using photometric selection criteria to down-select from a total of 493 nuclear transients to a sample of 26 sources, we then use follow-up UV imaging with the Neil Gehrels Swift Telescope, ground-based optical spectroscopy, and light curve fitting to classify them as 14 Type Ia supernovae (SNe Ia), 9 highly variable active galactic nuclei (AGNs), 2 confirmed TDEs, and 1 potential core-collapse supernova. We find it possible to filter AGNs by employing a more stringent transient color cut (g - r < -0.2 mag); further, UV imaging is the best discriminator for filtering SNe, since SNe Ia can appear as blue, optically, as TDEs in their early phases. However, when UV-optical color is unavailable, higher precision astrometry can also effectively reduce SNe contamination in the optical. Our most stringent optical photometric selection criteria yields a 4.5:1 contamination rate, allowing for a manageable number of TDE candidates for complete spectroscopic follow-up and real-time classification in the ZTF era. We measure a TDE per galaxy rate of 1.7 - 1.3 + 2.9 × 10 - 4 gal - 1 yr - 1 (90% CL in Poisson statistics). This does not account for TDEs outside our selection criteria, thus may not reflect the total TDE population, which is yet to be fully mapped.

The Ro60 autoantigen binds endogenous retroelements and regulates inflammatory gene expression

Autoantibodies target the RNA binding protein Ro60 in systemic lupus erythematosus (SLE) and Sjögren's syndrome. However, it is unclear whether Ro60 and its associated RNAs contribute to disease pathogenesis. We catalogued the Ro60-associated RNAs in human cell lines and found that among other RNAs, Ro60 bound an RNA motif derived from endogenous Alu retroelements. Alu transcripts were induced by type I interferon and stimulated proinflammatory cytokine secretion by human peripheral blood cells. Ro60 deletion resulted in enhanced expression of Alu RNAs and interferon-regulated genes. Anti-Ro60-positive SLE immune complexes contained Alu RNAs, and Alu transcripts were up-regulated in SLE whole blood samples relative to controls. These findings establish a link among the lupus autoantigen Ro60, Alu retroelements, and type I interferon.

Informational needs of patients with melanoma and their views on the utility of investigative tests

BACKGROUND

The aim of the study was to identify the informational needs of patients with melanoma on disease status and prognosis, and to ascertain their views on the utility of positron emission tomography (PET) and sentinel node biopsy (SNB).

PATIENTS AND METHODS

Patients attending the weekly melanoma outpatient clinic at St Thomas' Hospital London UK between February and August 2007 participated in this cross-sectional survey. Views of 106 melanoma patients were elicited using a face-to face semi-structured questionnaire.

RESULTS

The majority of participants wanted to know everything about their disease (88%). Prognostic information (> 85%) and information on palliative care input (97%) were highly valued. More than 50% expected the doctor to impart this information without negotiation. Nearly 70% of the responders who had previously had a PET scan felt they should decide if and when the scans should be performed. Fifty three percentage had undergone the SNB because the doctor had suggested it.

CONCLUSIONS

Patients with melanoma want detailed and prompt information about their disease including prognosis. Regular PET scans provide reassurance. The role of SNB is not clear to all patients.

Histone H3K4me3 binding is required for the DNA repair and apoptotic activities of ING1 tumor suppressor

Inhibitor of growth 1 (ING1) is implicated in oncogenesis, DNA damage repair, and apoptosis. Mutations within the ING1 gene and altered expression levels of ING1 are found in multiple human cancers. Here, we show that both DNA repair and apoptotic activities of ING1 require the interaction of the C-terminal plant homeodomain (PHD) finger with histone H3 trimethylated at Lys4 (H3K4me3). The ING1 PHD finger recognizes methylated H3K4 but not other histone modifications as revealed by the peptide microarrays. The molecular mechanism of the histone recognition is elucidated based on a 2.1 A-resolution crystal structure of the PHD-H3K4me3 complex. The K4me3 occupies a deep hydrophobic pocket formed by the conserved Y212 and W235 residues that make cation-pi contacts with the trimethylammonium group. Both aromatic residues are essential in the H3K4me3 recognition, as substitution of these residues with Ala disrupts the interaction. Unlike the wild-type ING1, the W235A mutant, overexpressed in the stable clones of melanoma cells or in HT1080 cells, was unable to stimulate DNA repair after UV irradiation or promote DNA-damage-induced apoptosis, indicating that H3K4me3 binding is necessary for these biological functions of ING1. Furthermore, N216S, V218I, and G221V mutations, found in human malignancies, impair the ability of ING1 to associate with H3K4me3 or to induce nucleotide repair and cell death, linking the tumorigenic activity of ING1 with epigenetic regulation. Together, our findings reveal the critical role of the H3K4me3 interaction in mediating cellular responses to genotoxic stresses and offer new insight into the molecular mechanism underlying the tumor suppressive activity of ING1.

Seroepidemiology and molecular epidemiology of the Chinese rotavirus

The Chinese rotavirus which causes epidemics of diarrhoea in adult humans was isolated in 1983. This virus, designated adult diarrhoea rotavirus (ADRV), resembles typical rotaviruses morphologically and has a genome made up of 11 discrete segments of double-stranded RNA. Because the Chinese rotavirus has a unique RNA pattern on polyacrylamide gel electrophoresis and is antigenically distinct from group A rotaviruses, it is tentatively included in group B. Infection with ADRV or ADRV-related viruses (as shown by serological study) is detected in human populations as widespread as mainland China, Hong Kong, Australia, the United States and Canada, and in some domestic animals. RNA co-electrophoresis has shown homology of isolates from 12 different outbreaks (with some minor variations at segments 10, 11, 3 and 5). cDNA probes and monoclonal antibodies have been prepared to improve the detection and further characterization of the virus.

Anterosuperior anchoring myringoplasty technique for anterior and subtotal perforations

Anterior and subtotal tympanic perforations are difficult perforations to repair. We used the anterosuperior anchoring technique to repair 105 of those perforations. Our technique utilizes a large temporalis fascia graft using an underlay technique with due emphasis on anterosuperior anchorage. The success rates in paediatric myringoplasty for consultant solo (J.R.K.) and trainees under supervision were 100% and 85.7%, respectively. The overall success rates in adult myringoplasty for consultant solo and trainees under supervision were 93.8% and 82.4%, respectively. Analysis of the 82 successful cases showed statistically significant improvement in air conduction thresholds after myringoplasty at 500 Hz (P < 0.01), 1 kHz (P < 0.05), 2 kHz (P < 0.01) and 4 kHz (P < 0.01). Our study showed that the anterosuperior anchoring technique produced excellent results in the repair of challenging anterior and subtotal perforations in both adults and children.

Paediatric day-stay myringoplasty: a review of 74 consecutive cases

Day-case surgery is particularly attractive for children, allowing post-operative recovery in the safe environment of the family home. Myringoplasty using the traditional method of underlay temporalis fasia is usually performed as an in-patient. From 1995 to 2000, 74 myringoplasties were performed in a dedicated paediatric day surgery unit at the Mayday University Hospital. We have retrospectively reviewed the outcome results of these procedures and reported them here. Only three patients required admission overnight (four per cent) and six grafts failed (8.5 per cent) complying with accepted standards. This series suggests that day-case surgery is a safe and desirable practice for children undergoing myringoplasty. However, there should be the facility for admission if required.

Topical bupivacaine in paediatric day-case tonsillectomy: a prospective randomized controlled trial

Post-operative pain and delayed oral intake are common reasons for failure of discharge in day-case tonsillectomy. A double blind prospective randomized study was devised to investigate the effectiveness of topical bupivacaine in reducing post-operative pain in paediatric day-case tonsillectomy. Ninety-nine patients aged between three and 16 years were recruited into the study. One group received bupivacaine soaked swabs tightly packed in their tonsillar fossae while the control group received saline-soaked swabs. The bupivacaine group was found to drink (p < 0.001) and eat (p = 0.006) earlier than the control group. The pain scores at one (p < 0.001), three (p < 0.001) and six (p < 0.001) hours post-operatively were also found to be lower in the bupivacaine group than the control group. We conclude that topical bupivacaine has a role in facilitating recovery in day-case tonsillectomy in children.

Idiopathic lymphoepithelial cyst of the parapharynx masquerading as peritonsillar abscess

We present a case of a 38-year-old man who was referred to us with a right-sided quinsy. However he was found to have a large lympho-epithelial cyst in his right parapharynx mimicking the signs of a quinsy to the unsuspecting eye. We describe this case to illustrate an unusual cause of a swelling of the lateral pharyngeal wall.

Isolated hypoglossal nerve palsy due to internal carotid artery dissection

A case of an isolated hypoglossal nerve palsy is reported. The differential diagnosis is discussed, in the context of the requirement for careful scrutiny of the entire course of the hypoglossal nerve on imaging, to detect underlying pathology remote from the tongue, and to avoid unnecessary invasive diagnostic procedures prompted by the appearance of a 'pseudomass' of the weak tongue both clinically and radiologically.

[Comparing cryopreserved with fresh corneas on clinical application in penetrating keratoplasty]

PURPOSE

To evaluate the role of cryopreserved corneas on penetrating keratoplasty (PKP) by comparing them with fresh corneas on clinical application.

METHODS

Third-six excellent condition patients were chosen and randomly divided into two groups. They were performed PKP by using fresh and cryopreserved corneas respectively. The graft transparency, epithelial healing speed of graft, tear membrane, graft thickness, endothelium density and visual acurity were emphasized respectively.

RESULTS

When fresh and cryopreserved corneas were used on PKP as the donor respectively, postoperative time to recover normal break-up time (BUT) was two to six months average (4.7 +/- 0.3) months and two to eight months, average (5.6 +/- 0.4) months and time to recover normal Schirmer's test was one to four months average (2.1 +/- 0.3) months and 1-3.5 months, average (1.7 +/- 0.5) months. The graft's thickness, stabilized visual acurity and graft's rejective rate were 0.56-0.68 mm (average 0.62 mm) vs 0.54-0.62 mm (average 0.59 mm), (0.46 +/- 0.03) vs (0.44 +/- 0.05) and 20% vs 19% respectively when fresh vs cryoperserved corneas. No statistical significance between fresh and cryopreserved corneas (P > 0.05). But the grafts behaved intact epithelium and continuing transparency when fresh corneas as donors, while the graft's epithelial defects healed after three to five days of the operation and edematous grafts were reclear after two to three weeks of the operation when cryopreserved corneas as donors. Graft's endothelium density in fresh corneas group 2,043-2,210 cells/mm2 (average 2,135 cells/mm2) was high than in cryopreserved corneas 1,240-1,860 cells/mm2 (average 1,672 cells/mm2) (P < 0.01).

CONCLUSION

There were no statistical significance on the transparent rate of grafts, grafts thickness, visual acurity and graft's rejective rate between fresh and cryopreserved corneas. But graft's epithelium healing was delayed and endothelium density was lower when cryopreserved corneas as donors.

Functional laryngeal dyskinesia: an important cause of stridor

Functional laryngeal dyskinesia is a disorder that presents with stridor. Failure to recognize its features can result in inappropriate investigation and treatment for a condition that has a psychogenic origin. The key feature in diagnosis is paradoxical vocal fold adduction on inspiration, as seen on fibre-optic nasendoscopy. This phenomenon together with the associated stridor may disappear after distraction techniques or when the patient is asleep. We present five such cases which presented to hospitals in south west London over a 12 month period.

When a mastoid swelling is not mastoiditis

A case is reported of swelling over the mastoid process due to subgaleal abscess possibly secondary to trivial cutaneous trauma. The diagnosis was difficult as subgaleal abscess is an extremely rare condition especially after the advent of the antibiotic era. The route of entry of the infection to the subgaleal space was unclear as there was no skin puncture. The absence of substantial trauma excluded subgaleal haematoma as a precondition. We would like to discuss the possible aetiologies and the management of this rare case in the light of the limited information available in the world literature.

Air rifle injury to the oropharynx. The essential role of computed tomography in deciding on surgical exploration

Gunshot wounds specific to the oropharynx are extremely rare with no reported cases of such injury in the world literature. The importance of such cases rests on the use of modern imaging techniques including computed tomography, magnetic resonance imaging, and vascular imaging in the making of management decisions and particularly in deciding the need for exploration of such an injury. In our case a conservative approach was adopted in view of the computed tomography finding and the stable clinical condition of the patient.

[Expression of human prp gene in prokaryotic cells using GST fusion protein expression system]

OBJECTIVE

To study the biological features of cell-surface protein PrPc, which is thought to be involved in the prion-associated diseases after converting to a proteinase-resistant isoform PrPSc posttranslationally, and to establish an effective immunologic diagnostic method using PrPc as antigen.

METHODS

Amplifying and cloning the human prp gene from lymphocytes of two normal Chinese, after confirmed by DNA sequence analysis, the genes were separately subcloned into a GST-fusion expression plasmid.

RESULTS

Sequence analysis showed that one contatined a point mutation that induced the 65th amino acid "Trp" inverting to a stop codon "TAG", whereas the other had the same sequence as the published standard prp gene. Both the standard and the mutated prp genes were separately subcloned into a GST fusion protein expression vector and expressed in the prokaryotic cells effectively. Western blot assay revealed that both of them expressed GST-PrP fusion proteins and could be recognized by PrP specific monoclonal antibody.

CONCLUSION

It suggests that human PrP protein can be expressed in the GST fusion protein expression system and the expressed proteins hold good immune-reactivity.

Facial paralysis after a road traffic accident

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[Expression of hepatitis B virus S genes in Ad5 vector]

The hepatitis B virus (HBV) S gene, PreS2 + S genes and the late phase expression cassette (MTI) + HBV S genes were separately cloned into Ad5 vector downstream of E3 promoter (pAd5 deltaE3 provided by Wyeth Co.). The above constructed plasmids and Ad5 DNA EcoR I A fragment were cotransfected into 293 cells. The progeny adenoviruses named rAd5S, rAd5MS, rAd5S2S were harvested for analysis. The recombinants were isolated and analyzed by PCR, using two primers specific to the HBV S genes. The expressed products were detected by ELISA and RIA. The recombinant containing MIT + HBV S genes (rAd5MS) was identified to be ELISA positive, whereas the other two recombinants (rAd5S, rAd5S2S) were negative to ELISA, but positive to RIA. The results indicated that adenovirus E3 early promoter could express the inserted foreign genes, and MIT worked well in the E3 region of Ad5 and could increase the expression capacity of the recombinants. The conditions for foreign gene expression and genetic stability of the recombinant viruses were studied in detail. There was no wild Ad5 discovered during the cotransfection experiments. The present study provides some experiences for studying adenovirus recombination.

Current views on geographic distribution and modes of infection of neurohelminthic diseases

Neurohelminthiases are more prevalent in geographic areas where environmental factors and poor sanitary conditions favor the parasitism between man and animals. In recent years, population shifts and rapid transport have facilitated the spread of certain helminthic diseases from endemic to non-endemic areas. Although many helminthic parasites are known to cause various human diseases afflicting many millions of people in the world, neurohelminthiases are often not diagnosed because they have been unrecognized by clinicians or confirmatory diagnostic tests are not easily available. Paragonimiasis and schistosomiasis (fluke diseases) are endemic in Asia, Africa and Central America; lesions in the central nervous system (CNS) due to ectopic parasitism of the preadult and adult flukes produce various clinical features that often mimic other diseases. In most cestodiasis (tapeworm disease), the adult worm that lodges in the alimentary tract does not involve the CNS; however, the larvae often enter the nervous system by migration or by metastasis via the systemic circulation, where they cause cystic lesions. Cysticercosis is the most common CNS helminthic infection especially in endemic areas where the parasitism between man and pigs is maintained. In other cestodiases, infections to man are often caused by ingestion of food or water contaminated with feces of the definitive hosts (mammals or man). Nematodes (roundworms) generally enter the CNS by ectopic migration of the infective larvae (larva migrans); the routes of infection to man vary with species of the nematodes, and the animal hosts they infest. Angiostrongylus cantonensis is a neurotropic nematode that requires the CNS of mammalian hosts for its growth; the third-stage larvae frequently invade skeletal muscles and the nervous system. Strongyloides, a gastrointestinal nematode, is known to cause CNS involvement in immunosuppressed patients. Recently, some nematodes heretofore unknown to cause human parasitism have been recognized as the causative agents of CNS infections.

Maturation of respiratory syncytial virus within HEp-2 cell cytoplasm

Electron microscopy of HEp-2 cells infected with respiratory syncytial virus (RSV) strain Long revealed the maturation of RSV on an ultrastructural level. The results showed that the virus maturated by two different pathways. In one of them, the virus assembled and matured before reaching the plasma membrane on the internal vesicle membrane within cytoplasm. The mature virus was delivered to the plasma membrane and to the extracellular space most likely by the transport vesicles and exocytosis. In the other pathway, the virus matured on the plasma membrane as described with other members of the family Paramyxoviridae. Using monoclonal antibodies (MoAbs), we localized viral nucleoprotein (NP) and envelope proteins in cytoplasm by immunoelectron microscopy (IEM).

Na(+)-K(+)-2Cl- cotransport and Cl- secretion evoked by heat-stable enterotoxin is microfilament dependent in T84 cells

We previously reported that adenosine 3',5'-cyclic monophosphate-mediated stimulation of Cl- secretion in the human intestinal epithelial cell line T84 is accompanied by significant remodeling of F-actin and that both the secretory and cytoskeletal responses may be inhibited by phalloidin derivatives, agents that polymerize actin and prevent dynamic reorganization of microfilaments. In contrast, the carbachol-elicited Cl- secretory response (Ca2+ mediated) was not attenuated by phalloidin (J. Clin. Invest. 87: 1903-1909, 1991). In the present study, we examine the effect of phalloidin on the Cl- secretory response elicited by the heat-stable enterotoxin of Escherichia coli (STa), which induces elevations in intracellular guanosine 3',5'-cyclic monophosphate. We find that apical administration of 1 microM STa results in a regionally restricted redistribution of F-actin confined to the basal pole of the cells. In monolayers pretreated with phalloidin, the Cl- secretory response to STa was inhibited by > 60%. Sequential treatment of phalloidin-loaded monolayers with STa followed by carbachol resulted in a synergistic secretory response that was not different from control (unloaded) monolayers. Examination of efflux/uptake through specific membrane transport pathways involved in STa-stimulated Cl- secretion indicated normal activation of apical Cl- and basolateral K+ channels under phalloidin-loaded conditions. The ability of STa-treated monolayers to pump Na+ in an absorptive direction was also unaffected by phalloidin. der phalloidin-loaded conditions, STa-stimulated Na(+)-K(+)-2Cl- cotransporter activity was reduced by approximately 60%, sufficient to account for the observed inhibition of net Cl- secretory response.(ABSTRACT TRUNCATED AT 250 WORDS)

Gamma/delta T-cell receptor expression in the jejunal epithelium of patients with dermatitis herpetiformis and coeliac disease

The density of jejunal intra-epithelial T cells expressing the gamma/delta form of the T-cell receptor is known to be increased in coeliac disease, the significance of which remains a mystery. The expression of the gamma/delta T-cell receptor in the jejunum of patients with dermatitis herpetiformis, coeliac disease, treated and untreated, and controls were studied. Expression of the gamma/delta T-cell receptor was significantly increased in patients with dermatitis hepetiformis (P < 0.0005) and in both untreated (P < 0.0005) and treated coeliac patients (P < 0.05) compared with controls. There were significant correlations between the indices of enteropathy, enterocyte height (P < 0.005) and villous height/crypt depth ratio (P < 0.0001), and expression of the gamma/delta T-cell receptor in the jejunum of all the patients. This argues against the hypothesis that gamma/delta T-cells have a fundamental role in the aetiology of gluten-sensitive enteropathy. It suggests that gamma/delta T cells may be involved in the effector arm of the mucosal immune response to cereal peptides in susceptible individuals.

Baculovirus expression of the ADRV gene 5 encoded protein produces an oligomerized, antigenic, and immunogenic VP6 protein

Adult diarrheal rotavirus (ADRV) is a currently noncultivatable group B human rotavirus responsible for epidemic outbreaks of gastroenteritis in China. Gene segment 5 of ADRV encodes the major inner capsid protein, VP6. ADRV gene 5 was inserted into a recombinant baculovirus by homologous recombination between baculovirus shuttle plasmid pACYM1-AD5 and AcNPV genomic DNA. Baculovirus recombinants were selected visually and plaque purified and VP6 expression was detected by Coomassie staining of PAGE-separated proteins. The baculovirus-expressed gene 5 polypeptide is 44 kDa, the same as for the major inner capsid protein present on EDTA-treated ADRV virions and in vitro-expressed VP6 protein. The expressed protein is oligomeric and in the absence of reducing agents multimerizes to apparent trimer, hexamer, and greater molecular mass as assayed by SDS-PAGE. The VP6 protein is immunoprecipitable by hyperimmune serum to ADRV, human ADRV convalescent serum, by a group B-specific monoclonal antibody and by porcine group B rotavirus infection serum. The baculovirus-expressed protein is immunogenic and antibodies to the expressed protein recognize ADRV virions. The ADRV VP6 protein should be useful for developing diagnostic assays for serum antibodies to group B rotavirus as well as for generating hyperimmune serum and monoclonal antibodies for detecting viral antigen from ADRV and other group B rotaviruses.

Coding assignments of the genome of adult diarrhea rotavirus

Adult diarrhea rotavirus (ADRV) has caused epidemics of diarrhea in China since 1982 and remains the only group B rotavirus associated with widespread disease in humans. We recently characterized the proteins of ADRV and have now proceeded to identify the gene segments encoding each protein. Viral RNA transcripts were synthesized in vitro with the endogenous viral RNA polymerase and separated by electrophoresis in agarose. The individual transcripts were translated in a cell-free system using nuclease-treated rabbit reticulocyte lysates. The translation products were compared with polypeptides found in purified virus and were characterized by SDS-PAGE, immunoprecipitation, and Western blot analysis using antisera to double- and single-shelled virions, virus cores, and monoclonal antibodies. Furthermore, individual RNA transcripts were hybridized to total dsRNA to determine their genomic origin. Based on this analysis, the core polypeptides VP1, VP2 and VP3 are encoded by segments 1, 2, and 3, respectively. The main polypeptides in the inner capsid, VP6, and the outer capsid, VP4 and VP7, are encoded by segments 6, 4, and 8 respectively. Segments 5, 7, and 9 code for 60, 45, and 30 kDa nonstructural polypeptides. Two other nonstructural polypeptides (24 and 25 kDa) are derived from gene segment 11. Gene segment 10 codes for a 26 kDa polypeptide that is precipitated with serum to ADRV and may be a structural protein VP9. With this exception, gene coding assignments of ADRV are comparable to those of the group A rotaviruses. Our results have clear implications for further work in cloning, sequencing, and expression genes of ADRV and can provide direction towards understanding the origin and the evolution of this virus.

Identification of Hantaan virus-related structures in kidneys of cadavers with haemorrhagic fever with renal syndrome

The etiologic agent of haemorrhagic fever with renal syndrome (HFRS), Hantaan virus, was first isolated in 1976. Since then numerous Hantaan-like viruses have been isolated and five serotypes of Hantavirus have been recognized. Serological studies indicate that these viruses are globally distributed, with each serotype occurring in specific areas. Hantaan virus has been intensively studied antigenically, biochemically, and genetically. However there is still a paucity of information on the pathogenesis of Hantaan virus in the human host. In this paper, we report the detection by thin section immune electron microscopy of the occurrence of numerous dense precipitates, typical inclusion bodies, a surface antigen layer, as well as Hantaan virion-like structures in the kidneys of patients that died during the acute phase of HFRS. These findings may shed some light on understanding the pathogenesis of HFRS in target organs most affected by the disease, such as the kidneys.

Identification of the gene encoding the group B rotavirus VP7 equivalent: primary characterization of the ADRV segment 9 RNA

Gene segment 9 of the adult diarrheal rotavirus, ADRV, has been cloned, and the full-length gene 9 cDNA has been sequenced. Sequences at the 5' and 3' termini of the gene 9 double-stranded RNA were confirmed by direct RNA sequencing. The ninth RNA segment is 814 bases in length with a single open reading frame beginning at base 10 and terminating at base 757. The encoded polypeptide contains 249 amino acids with a calculated molecular weight of 28.5 kDa. The protein contains three potential N-linked glycosylation sites and a hydrophobic signal-like sequence at its amino terminus. A search of the NBRF protein data base with the encoded polypeptide revealed extensive similarities with VP7 proteins from a number of group A rotaviruses. Direct comparisons of the ADRV gene 9 polypeptide and the group A rotavirus VP7 demonstrate that the two proteins share 78% amino acid similarity and 28% identity as well as predicted secondary structure similarities. These findings suggest that the ADRV gene segment 9 encodes the VP7 polypeptide equivalent of group A rotaviruses.

A specificity enhancer for polymerase chain reaction

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cDNA cloning of each genomic segment of the group B rotavirus ADRV: molecular characterization of the 11th RNA segment

The group B noncultivatable rotavirus, ADRV, was purified from infected stool specimens. Double-stranded RNA was extracted, polyadenylated, reverse transcribed into cDNA, and cloned into plasmid vector pAT153. Each cDNA clone hybridized to a single ADRV RNA segment and cDNA clones of each genomic RNA segment were identified. Sequencing of genomic RNA and a full-length cDNA clone (AD63) determined that ADRV RNA segment 11 is 631 bases in length and contains a single open reading frame of 170 amino acids with a calculated molecular weight of 19.9 kDa and a pl of 6.2. The RNA 5'- and 3'-termini contain untranslated regions of 58 and 63 bases, respectively, and are complementary to each other. A comparison of encoded ADRV gene 11 amino acids with the NS26 protein of group A rotaviruses demonstrates a distant similarity between the two proteins. Further analysis and use of these ADRV clones should aid in determining the gene coding assignments for group B proteins as well as for diagnostic detection of group B or ADRV-specific nucleic acids in specimens.

Investigation of an outbreak of adult diarrhea rotavirus in China

In 1987 an epidemic of diarrhea associated with adult diarrhea rotavirus (ADRV) occurred in Qinhuangdao City, China, affecting more than 200 persons and causing 2 deaths. The outbreak was introduced by a person returning from an epidemic area and was spread initially to his family members and subsequently to the entire community. Adults were at greater risk of diarrhea than children 0-4 y of age and, the duration of illness increased significantly with increasing age. ADRV was identified by ELISA and electron microscopy. The electropherotypes of all positive specimens were identical, consistent with the single point-source introduction of the virus. Seroconversion was detected in 6 of 7 ill persons with a blocking ELISA. Both asymptomatic infection and person-to-person spread identified in this epidemic suggest that current emphasis on preventing waterborne transmission may not control the introduction of ADRV into new areas. The predisposition of adults for more severe disease with ADRV is similar to the pattern observed with other enteric viruses such as the Norwalk agent and hepatitis A.

Seroepidemiology of adult diarrhea rotavirus in China, 1977 to 1987

In 1982, large outbreaks of diarrhea that were caused by group B adult diarrhea rotavirus (ADRV) occurred throughout the People's Republic of China. Until 1982, group B rotavirus had never been associated with disease in humans. To determine whether ADRV was a new virus introduced in 1982 or had been present before that time, we examined antibody titers of ADRV in gamma globulin (pooled immunoglobulin) pools that were prepared during 1977 to 1987 in four cities in the People's Republic of China (Shanghai, Lanzhou, Wuhan, and Chandu). ADRV antibodies were assayed by using a blocking enzyme-linked immunosorbent assay. Antibodies were present in most Chinese gamma globulins tested, including those collected in Shanghai before the 1982 epidemic, and absent from American reference pools. The highest titers of antibody to ADRV (3,200) were found in gamma globulins collected in 1983 in Shanghai just after the epidemic, and these were fourfold higher than titers present in the preceding years. The quality of the gamma globulins stored for up to 12 years was tested by measuring levels of immunoglobulin G to group A rotavirus; these were equally high in gamma globulin pools prepared in the United States and in all samples from the People's Republic of China. Serum samples from patients from an outbreak of ADRV had elevated titers to ADRV 3 and 16 months after the onset of symptoms. These findings, as well as other epidemiologic findings on ADRV, suggest that the organism is an important and continuing cause of diarrhea in the People's Republic of China, was present before the first epidemic in 1982, and represents a risk to surrounding populations in Asia.

Rapid diagnosis of adult diarrhea rotavirus (ADRV): detection of viral antigens in faecal samples using staphylococcal co-agglutination test

Staphylococcus aureus Cowan I rich in protein A when sensitized with guinea pig antiserum to adult diarrhea rotavirus (ADRV) at 1:16 gave a strong co-agglutination with ADRV-positive faecal samples as previously confirmed by electron microscopy (EM) and enzyme-linked immunosorbent assay (ELISA). The bacteria sensitized with normal guinea pig serum did not give any co-agglutination. Blocking tests using rabbit ADRV-specific antiserum for the treatment of twelve ADRV-positive samples abolished the reaction. All the fifty ELISA-confirmed ADRV-positive faecal samples gave positive co-agglutination, whereas all the forty-eight ELISA-negative faecal samples from healthy subjects gave negative results. The test has been proved to be rapid, simple, specific, and economic, useful for rapid diagnosis even in remote areas, so that the ADRV infection can definitely be differentiated from some of acute bacterial diarrheas.

Myasthenia gravis: population differences in disease expression and acetylcholine receptor antibody titers between Chinese and Caucasians

Clinical features and anti-acetylcholine receptor (AChR) titers were compared in Chinese (n = 258) and Caucasian (n = 258) myasthenia gravis populations. The former had more early onset and ocular cases, lacked the Caucasian late onset peak, and had fewer severe cases. The distribution of anti-AChR titers was broadly similar in the two populations, and their sera reacted equally well with AChR in both races. The significantly lower (chi 2 = 14.6; p less than 0.001) median anti-AChR titer in the Chinese population can be accounted for by the higher frequency of ocular cases and lower frequency of moderate or severely affected cases.

Effects of two negative staining methods on the Chinese atypical rotavirus

The Chinese atypical (Group B) rotavirus, previously called the adult diarrhoea rotavirus (ADRV), was examined by transmission electron microscopy using either uranyl acetate or potassium phosphotungstate (PTA) as negative stains. Complete rotavirus particles were seen using uranyl acetate which were indistinguishable morphologically from typical rotaviruses. In the same preparations virus particles with differing degrees of degradation were seen after staining with PTA. This effect was not related to pH of the PTA and could be prevented by fixation of the specimen by 0.1 per cent glutaraldehyde. It is concluded that the use of PTA can give rise to falsely negative results for specimens containing this virus.

Genome analysis of human rotaviruses by oligonucleotide mapping of isolated RNA segments

The genomes of adult diarrhoea rotaviruses isolated in different parts of China during winter outbreaks in 1983 and 1984 were compared by segmental oligonucleotide (ON) mapping. The RNA profiles of most of the isolates were indistinguishable but it was found that some corresponding RNA segments had identical or very closely related ON maps whereas others differed considerably. This finding can be taken to suggest that the strains compared may be genetically related by a natural reassortment event. The genomes of cocirculating group A rotaviruses isolated in Scotland during winter outbreaks in 1981/82 were also compared. The ON maps of corresponding RNA segment differed extensively irrespective of whether or not the segments comigrated on gels.