Safety, immunogenicity and protective effect of sequential vaccination with inactivated and recombinant protein COVID-19 vaccine in the elderly: a prospective longitudinal study

The safety and efficacy of COVID-19 vaccines in the elderly, a high-risk group for severe COVID-19 infection, have not been fully understood. To clarify these issues, this prospective study followed up 157 elderly and 73 young participants for 16 months and compared the safety, immunogenicity, and efficacy of two doses of the inactivated vaccine BBIBP-CorV followed by a booster dose of the recombinant protein vaccine ZF2001. The results showed that this vaccination protocol was safe and tolerable in the elderly. After administering two doses of the BBIBP-CorV, the positivity rates and titers of neutralizing and anti-RBD antibodies in the elderly were significantly lower than those in the young individuals. After the ZF2001 booster dose, the antibody-positive rates in the elderly were comparable to those in the young; however, the antibody titers remained lower. Gender, age, and underlying diseases were independently associated with vaccine immunogenicity in elderly individuals. The pseudovirus neutralization assay showed that, compared with those after receiving two doses of BBIBP-CorV priming, some participants obtained immunological protection against BA.5 and BF.7 after receiving the ZF2001 booster. Breakthrough infection symptoms last longer in the infected elderly and pre-infection antibody titers were negatively associated with the severity of post-infection symptoms. The antibody levels in the elderly increased significantly after breakthrough infection but were still lower than those in the young. Our data suggest that multiple booster vaccinations at short intervals to maintain high antibody levels may be an effective strategy for protecting the elderly against COVID-19.

High throughput screening of pure silica zeolites for CF4 capture from electronics industry gas

The capture and separation of CF4 from CF4/N2 mixture gas is a crucial issue in the electronics industry, as CF4 is a commonly used etching gas and the ratio of CF4 to N2 directly affects process efficiency. Utilizing high-throughput computational screening techniques and grand canonical Monte Carlo (GCMC) simulations, we comprehensively screened and assessed 247 types of pure silicon zeolite materials to determine their adsorption and separation performance for CF4/N2 mixtures. Based on screening, the relationships between the structural parameters and adsorption and separation properties were meticulously investigated. Four indicators including adsorption selectivity, working capacity, adsorbent performance score (APS), and regenerability (R%) were used to evaluate the performance of adsorbents. Based on the evaluation, we selected the top three best-performing zeolite structures for vacuum swing adsorption (LEV, AWW and ESV) and pressure swing adsorption (AVL, ZON, and ERI) processes respectively. Also, we studied the preferable adsorption sites of CF4 and N2 in the selected zeolite structures through centroid density distributions at the molecule level. We expect the study may provide some valuable guidance for subsequent experimental investigations on adsorption and separation of CF4/N2.

Using omics approaches to dissect the therapeutic effects of Chinese herbal medicines on gastrointestinal cancers

Chinese herbal medicines offer a rich source of anti-cancer drugs. Differences between the pharmacology of Chinese herbal medicines and modern synthetic chemicals hinder the development of drugs derived from herbal products. To address this challenge, novel omics approaches including transcriptomics, proteomics, genomics, metabolomics, and microbiomics have been applied to dissect the pharmacological benefits of Chinese herbal medicines in cancer treatments. Numerous Chinese herbal medicines have shown potential anti-tumor effects on different gastrointestinal (GI) cancers while eliminating the side effects associated with conventional cancer therapies. The present study aimed to provide an overview of recent research focusing on Chinese herbal medicines in GI cancer treatment, based on omics approaches. This review also illustrates the potential utility of omics approaches in herbal-derived drug discovery. Omics approaches can precisely and efficiently reveal the key molecular targets and intracellular interaction networks of Chinese herbal medicines in GI cancer treatment. This study summarizes the application of different omics-based approaches in investigating the effects and mechanisms of Chinese herbal medicines in GI cancers. Future research directions are also proposed for this area of study.

[Modern research on Chinese medicine based on single-cell omics: technologies and strategies]

As one of the most advanced technologies, single-cell omics technology develops rapidly in recent years. Based on different technical strategies, it enables unbiased and high-throughput access to multiple omics information at single-cell resolution. So far, single-cell omics technology, by virtue of its great powder in resolving tissue heterogeneity, has become a revolutionary tool to deeply understand the functional structure of tissues, reveal complex disease processes, and elucidate drug mechanisms of action. In view of the technical challenges in deconstructing the complexity of Chinese medicine and clarifying the modern scientific connotation of traditional Chinese medicine(TCM) theory, single-cell omics technology has huge application potential in the discovery of pharmacodynamic substances, construction of action networks, and elucidation of integrated regulatory mechanisms, which brings new opportunities for modern research in TCM. The present study briefly introduced three representative single-cell omics technologies, i.e., single-cell transcriptome sequencing, spatial transcriptomics, and single-cell multimodal omics, and their main application patterns. On this basis, an outlook was proposed on the strategies and applications for modern research in TCM using single-cell omics technology.

Src-homology domain 2 containing protein tyrosine phosphatase-1 (SHP-1) directly binds to proto-oncogene tyrosine-protein kinase Src (c-Src) and promotes the transcriptional activation of connexin 43 (Cx43)

The prevalence of atrial fibrillation (AF), which is one of the common arrhythmias in clinics, is increasing sharply and has affected millions of patients, which is expected to triple by 2050. The purpose of the study was to explore the regulatory relationship between Src-homology domain 2 containing protein tyrosine phosphatase-1 (SHP-1) and proto-oncogene tyrosine-protein kinase Src (c-Src) and the regulation of Connexins 43 (Cx43), and its effect on AF was also studied. Mouse atrial myocyte line (HL-1 cell line) was used as the research object. After overexpression of SHP-1, the expressions of p-c-Src, Cx43, and SHP-1 were detected by Western blot and cellular immunofluorescence, respectively. The location and interaction of SHP-1 and c-Src in the cells were detected by immunofluorescence co-localization and co-immunoprecipitation (Co-IP). The regulation of c-Src and Cx43 was detected by DNA pull down, chromatin co-immunoprecipitation (CHIP), and dual-luciferase reporter system. The results revealed that overexpression of SHP-1 could inhibit the phosphorylation and activation of c-Src and increase the expression of Cx43. Moreover, there was a direct binding between SHP-1 and c-Src, and c-Src could bind to the promoter region of Cx43 and inhibit the transcription of Cx43. In conclusion, SHP-1 could bind to c-Src and inhibit the activity of c-Src, thus enhancing the transcriptional activation of Cx43 and improving the function of gap junction.

[A novel nomogram for individualized preoperative prediction of lymph node metastasis in patients with intrahepatic cholangiocarcinoma]

Objective: Constructing and validating a nomogram model for preoperative prediction of intrahepatic cholangiocarcinoma (ICC) lymph node metastasis to assist decision making during surgery. Methods: Retrospectively collecting the clinical and pathological data of 1 031 ICC patients who underwent partial hepatectomy at Eastern Hepatobiliary Surgery Hospital of Naval Military Medical University,General Hospital of Eastern Theater Command,or Zhongda Hospital Southeast University from January 2003 to January 2014. There were 682 males and 349 females; mean age was 54.7 years(range:18 to 82 years). There were 562 patients who underwent lymph node dissection and 469 patients who did not. Among the patients in the dissection group,Lasso regression method was used to filtrate preoperative variables related to lymph node metastasis and establish a nomogram. Bootstrap method was used to internally validate the discrimination of the nomogram,and the accuracy of the nomogram was assessed by using calibration curves. Patients were divided into low-moderate and high-risk groups based on model prediction probability. Propensity score matching(PSM) was used to analyze the overall survival (OS) and recurrence-free survival (RFS) of patients with and without lymph node dissection in the two groups,and to judge the importance of lymph node dissection in the two groups. Results: Six factors related to ICC lymph node metastasis were determined by Lasso regression,including hepatitis B surface antigen,CA19-9,age,lymphadenopathy,carcinoembryo antigen and maximum tumor diameter. These factors were integrated into a nomogram to predict ICC lymph node metastasis. The aera under curve value was 0.764,and the C-index was 0.754. Stratified analysis showed that OS and RFS in the high-risk group of lymph node metastasis were significantly lower than those in the low-medium risk group(median OS:14.6 months vs. 27.0 months,P<0.01; median RFS:9.1 months vs. 15.5 months,P<0.01). In the high-risk group,the median OS was 16.7 months and 6.3 months(Log-rank test: P=0.187;Wilcoxon test:P=0.046),and the median RFS was 11.0 months and 4.8 months(P=0.403),respectively in the lymph node dissection group and undissected group after PSM. In the low-medium-risk group,the median OS was 22.7 months and 26.7 months(P=0.288),and the median RFS was 13.0 months and 14.5 months(P=0.306),respectively in the lymph node dissection group and undissected group after PSM. Conclusions: The nomogram could be used for preoperative prediction of lymph node metastasis and prognostic stratification in patients with ICC. For patients with high risk of lymph node metastasis predicted by the model,active dissection should be performed. For patients predicted to be at low-moderate risk,lymph node dissection might be optional in some specific cases.

Long noncoding RNA FAM66C promotes tumor progression and glycolysis in intrahepatic cholangiocarcinoma by regulating hsa-miR-23b-3p/KCND2 axis

Long noncoding RNAs (lncRNAs) are known to be the important regulators in cancer progression. However, the role of lncRNA FAM66C (FAM66C) is yet to be investigated in intrahepatic cholangiocarcinoma (ICC). This study aimed to investigate the effects and related mechanisms of FAM66C in ICC. Human ICC tissues and cell lines were collected. The expression levels of FAM66C, hsa-miR-23b-3p (miR-23b-3p), and KCND2 were detected by qRT-RCR. The transfection experiments were employed to measure the effect of FAM66C on cell viabilities, migration, and invasion in ICC cells by CCK-8, transwell assays. Glycolysis was investigated by glucose consumption, lactate production and ATP levels. The dual-luciferase reporter and RNA pull down assays were conducted as a means of confirming the interactions between FAM66C, miR-23b-3p, and KCND2. Furthermore, the levels of the EMT-associated proteins (KCND2, GLUT1, PKM2, and LDHA) in ICC cells were detected by western blot. FAM66C was increased in ICC tissues and cells, increased cell viability, glycolysis, migration and invasion, and decreased apoptosis were shown in FAM66C overexpressing cells. Mechanistic analyses revealed that FAM66C regulated the downstream target gene KCND2 by sponging miR-23b-3p. FAM66C effect on ICC was further validated in murine xenograft assays. FAM66C knockdown cells gave rise to tumors that were smaller in size, consistent with the role of FAM66C as a promoter of in vivo tumor growth. These data revealed that FAM66C was able to drive ICC tumor progression and glycolytic activity via the miR-23b-3p/KCND2 axis, indicating FAM66C may be a viable target for treating ICC.

Upregulation of long noncoding RNA W42 promotes tumor development by binding with DBN1 in hepatocellular carcinoma

BACKGROUND

Hepatocellular carcinoma (HCC) is a malignancy found globally. Accumulating studies have shown that long noncoding RNAs (lncRNAs) play critical roles in HCC. However, the function of lncRNA in HCC remains poorly understood.

AIM

To understand the effect of lncRNA W42 on HCC and dissect the underlying molecular mechanisms.

METHODS

We measured the expression of lncRNA W42 in HCC tissues and cells (Huh7 and SMMC-7721) by quantitative reverse transcriptase polymerase chain reaction. Receiver operating characteristic curves were used to assess the sensitivity and specificity of lncRNA W42 expression. HCC cells were transfected with pcDNA3.1-lncRNA W42 or shRNA-lncRNA W42. Cell functions were detected by cell counting Kit-8 (CCK-8), colony formation, flow cytometry and Transwell assays. The interaction of lncRNA W42 and DBN1 was confirmed by RNA immunoprecipitation and RNA pull down assays. An HCC xenograft model was used to assess the role of lncRNA W42 on tumor growth in vivo. The Kaplan-Meier curve was used to evaluate the overall survival and recurrence-free survival after surgery in patients with HCC.

RESULTS

In this study, we identified a novel lncRNA (lncRNA W42), and investigated its biological functions and clinical significance in HCC. LncRNA W42 expression was upregulated in HCC tissues and cells. Overexpression of lncRNA W42 notably promoted the proliferative and invasion of HCC, and inhibited cell apoptosis. LncRNA W42 directly bound to DBN1 and activated the downstream pathway. LncRNA W42 knockdown suppressed HCC xenograft tumor growth in vivo. The clinical investigation revealed that HCC patients with high lncRNA W42 expression exhibited shorter survival times.

CONCLUSION

In vitro and in vivo results suggested that the novel lncRNA W42, which is upregulated in HCC, may serve as a potential candidate prognostic biomarker and therapeutic target in HCC patients.

A recombinant influenza virus with a CTLA4-specific scFv inhibits tumor growth in a mouse model

Oncolytic viruses (OV) have shown excellent safety and efficacy in preclinical and clinical studies. Influenza A virus (IAV) is considered a promising oncolytic virus. In this report, we generated a recombinant influenza virus expressing an immune checkpoint blockade agent targeting CTLA4. Using reverse genetics, a recombinant influenza virus, termed rFlu-CTLA4, encoding the heavy chain of a CTLA4 antibody on the PB1 segment and the light chain of the CTLA4 antibody on the PA segment was produced. RFlu-CTLA4 could replicate to high titers, and antibodies were produced in the allantoic fluid of infected eggs. Furthermore, the selective cytotoxicity of the virus was higher in various hepatocellular carcinoma cancer cell lines than in the normal cell line L02 in vitro, as indicated by MTS assays. More importantly, in a subcutaneous H22 mouse hepatocarcinoma model, intratumoral injections of rFlu-CTLA4 inhibited the growth of treated tumors and increased the overall survival of mice compared with injections of the PR8 virus. Taken together, these results warrant further exploration of this novel recombinant influenza virus for its potential use as a single or combination agent for cancer immunotherapy.

Long non-coding ribonucleic acid W5 inhibits progression and predicts favorable prognosis in hepatocellular carcinoma

BACKGROUND

Accumulating evidence has revealed that several long non-coding ribonucleic acids (lncRNAs) are crucial in the progress of hepatocellular carcinoma (HCC).

AIM

To classify a long non-coding RNA, i.e., lncRNA W5, and to determine the clinical significance and potential roles of lncRNA W5 in HCC.

METHODS

The results showed that lncRNA W5 expression was significantly downregulated in HCC cell lines and tissues. Analysis of the association between lncRNA W5 expression levels and clinicopathological features suggested that low lncRNA W5 expression was related to large tumor size (P < 0.01), poor histological grade (P < 0.05) and serious portal vein tumor thrombosis (P < 0.05). Furthermore, Kaplan-Meier survival analysis showed that low expression of lncRNA W5 predicts poor overall survival (P = 0.016).

RESULTS

Gain-of-loss function experiments, including cell counting kit8 assays, colony formation assays, and transwell assays, were performed in vitro to investigate the biological roles of lncRNA W5. In vitro experiments showed that ectopic overexpression of lncRNA W5 suppressed HCC cell proliferation, migration and invasion; conversely, silencing of lncRNA W5 promoted cell proliferation, migration and invasion. In addition, acting as a tumor suppressor gene in HCC, lncRNA W5 inhibited the growth of HCC xenograft tumors in vivo.

CONCLUSION

These results showed that lncRNA W5 is down-regulated in HCC, and it may suppress HCC progression and predict poor clinical outcomes in patients with HCC. LncRNA W5 may serve as a potential HCC prognostic biomarker in addition to a therapeutic target.

Increased circulating level of interleukin-6 and CD8+ T cell exhaustion are associated with progression of COVID-19

BACKGROUND

Coronavirus disease 2019 (COVID-19) is pandemic. It is critical to identify COVID-19 patients who are most likely to develop a severe disease. This study was designed to determine the clinical and epidemiological features of COVID-19 patients associated with the development of pneumonia and factors associated with disease progression.

METHODS

Seventy consecutive patients with etiologically confirmed COVID-19 admitted to PLA General Hospital in Beijing, China from December 27, 2019 to March 12, 2020 were enrolled in this study and followed-up to March 16, 2020. Differences in clinical and laboratory findings between COVID-19 patients with pneumonia and those without were determined by the χ2 test or the Fisher exact test (categorical variables) and independent group t test or Mann-Whitney U test (continuous variables). The Cox proportional hazard model and Generalized Estimating Equations were applied to evaluate factors that predicted the progression of COVID-19.

RESULTS

The mean incubation was 8.67 (95% confidence interval, 6.78-10.56) days. Mean duration from the first test severe acute respiratory syndrome coronavirus 2-positive to conversion was 11.38 (9.86-12.90) days. Compared to pneumonia-free patients, pneumonia patients were 16.5 years older and had higher frequencies of having hypertension, fever, and cough and higher circulating levels of neutrophil proportion, interleukin-6, low count (< 190/µl) of CD8+ T cells, and neutrophil/lymphocyte ratio. Thirteen patients deteriorated during hospitalization. Cox regression analysis indicated that older age and higher serum levels of interleukin-6, C-reactive protein, procalcitonin, and lactate at admission significantly predicted the progression of COVID-19. During hospitalization, circulating counts of T lymphocytes, CD4+ T cells, and CD8+ T cells were lower, whereas neutrophil proportion, neutrophil/lymphocyte ratio, and the circulating levels of interleukin-6, C-reactive protein, and procalcitonin were higher, in pneumonia patients than in pneumonia-free patients. CD8+ lymphocyte count in pneumonia patients did not recover when discharged.

CONCLUSIONS

Older age and higher levels of C-reactive protein, procalcitionin, interleukin-6, and lactate might predict COVID-19 progression. T lymphocyte, especially CD8+ cell-mediated immunity is critical in recovery of COVID-19. This study may help in predicting disease progression and designing immunotherapy for COVID-19.

Somatic mutation profiling of liver and biliary cancer by targeted next generation sequencing

Liver and biliary cancers are highly lethal cancer types lacking effective treatments. The somatic mutations, particularly those with low mutant allele frequencies, in Chinese patients with liver and biliary cancer have not been profiled, and the frequency of patients benefiting from targeted therapy has not been studied. The present study evaluated the tumor tissues of 45 Chinese patients with hepatocellular carcinoma (HCC) and 12 Chinese patients with biliary tract cancer (BTC) by targeted next generation sequencing, with an average coverage of 639×, to identify alterations in 372 cancer-related genes. A total of 263 variants were identified in 139 genes, with 85.6% of these variants not previously reported in the Catalogue Of Somatic Mutations In Cancer database, and the mutation profile was different from the current datasets, including The Cancer Genome Atlas dataset and the National Cancer Center Japan (NCC_JP) dataset. Patients with hepatitis B virus (HBV) infection harbored more mutations than those without HBV infection, and the mutations in HBV carriers occurred preferentially in genes involved in vascular endothelial growth factor signaling pathways. Mutations in fibroblast growth factor and RAS signaling pathways were enriched in patients with cirrhosis, and alterations in interleukin and transforming growth factor signaling pathways were more frequently identified in individuals with abnormal bilirubin expression. Of all the patients, 7% exhibited variants in the target of sorafenib, and 42% harbored variants in the targets of drugs that have been approved to treat other types of cancer. These findings indicate diverse HCC/BTC variants patterns in different populations, and that the mutation load and patterns are correlated with clinical features. Further clinical studies are now warranted to evaluate the efficacies of other targeted drugs besides sorafenib in the treatment of patients with liver and biliary cancer.

Downregulation of BRAF-activated non-protein coding RNA in patients with hepatitis B virus-associated hepatocellular carcinoma

Long non-coding RNAs (lncRNAs) have been investigated as a novel class of regulators of cellular processes, including cell growth, apoptosis and carcinogenesis. lncRNA BRAF-activated non-protein coding RNA (BANCR) has recently been revealed to be involved in tumorigenesis of numerous types of cancer, including papillary thyroid carcinoma, melanoma, non-small cell lung cancer and colorectal cancer. However, the expression profiles and biological relevance of lncRNA BANCR in hepatocellular carcinoma (HCC) has not yet been reported. In the present study, the expression level of BANCR in tumor tissues and para-cancerous tissues was determined by reverse transcription-quantitative polymerase chain reaction in patients with hepatitis B virus (HBV)-associated HCC, and its association with clinicopathological characteristics of patients was analyzed. The results demonstrated that the expression level of BANCR was significantly reduced in tumor tissues in comparison with in para-cancerous tissues (P<0.001). Furthermore, the present study demonstrated that BANCR expression level was closely associated with serum α-fetoprotein levels (P<0.01) and HCC tumor number (P<0.05). To the best of our knowledge, these results revealed for the first time that BANCR downregulated in patients with HBV-associated HCC and BANCR expression level may be a potential valuable diagnosis and therapeutic biomarker in HCC.

Decreased expression of long non-coding RNA LOC728290 in human hepatocellular carcinoma

Hepatocellular carcinoma (HCC) is a leading cause of cancer-associated mortality worldwide. Despite progress in the diagnosis and treatment of HCC, prognosis remains unfavorable. Long non-coding RNAs (lncRNAs) are emerging as important factors in tumorigenesis and cancer progression; however, the underlying molecular mechanisms and clinical significance of lncRNAs in HCC remain largely unknown. The present study examined the expression pattern and clinical significance of a novel lncRNA, LOC728290, in HCC. Expression of LOC728290 was markedly decreased in HCC tissues compared with adjacent non-tumor liver tissues, as detected using the reverse transcription-quantitative polymerase chain reaction (RT-qPCR). The area under the receiver operating characteristic curve for LOC728290 was 0.728. The expression of LOC728290 was associated with the level of α-fetoprotein and microvascular invasion. Furthermore, patients with low LOC728290 expression exhibited decreased recurrence-free survival times (P<0.05) compared with those with high LOC728290 expression. The results of the present study indicated that downregulation of LOC728290 in patients with HCC may be a powerful tumor biomarker, with potential clinical applications in prognosis as well as a therapeutic target.

Characterization and expression of Megalobrama amblycephala toll-like receptor 22 involved in the response to Aeromonas hydrophila

The toll-like receptors (TLR) tlr22 was identified and characterized for the first time in one of the economically most important freshwater fish species in China, Megalobrama amblycephala. The full-length cDNA (4039 bp) of M. amblycephala tlr22 contains an open reading frame of 2706 bp, encoding a 901 amino-acid long polypeptide. The putative polypeptide contains 16 leucine-rich repeat (LRR) motifs, an LRR C-terminal, a transmembrane region and a cytoplasmic toll-interleukin-1 receptor (TIR) domain. Phylogenetic analyses revealed that M. amblycephala Tlr22 shared the closest relationship with a grass carp ortholog. tlr22 was constitutively expressed in nine tissues and during 10 developmental stages studied, albeit with varying expression levels. Along with many pathological changes observed after Aeromonas hydrophila bacterium infection, tlr22 and myd88 mRNA were significantly upregulated in blood, head kidney, spleen and intestine, indicating that tlr22 is involved in the immune response. These results provide an insight into tlr22 regulation mechanisms in the innate immune response to bacterial infection.

Human Basic Fibroblast Growth Factor Inhibits Tau Phosphorylation via the PI3K/Akt-GSK3β Signaling Pathway in a 6-Hydroxydopamine-Induced Model of Parkinson's Disease

BACKGROUND

Basic fibroblast growth factor (bFGF) has been increasingly investigated due to its neuroprotection in neurodegenerative disorders. Because there are still no cures for any of these disorders, it is crucial to identify new therapeutic targets and screen potential drugs. The increased phosphorylation of tau at Ser396 leads to intracellular tau accumulation, which forms neurofibrillary tangles in Parkinson's disease (PD). In this study, neuroprotection by bFGF was observed, and the mechanisms related to its regulation of phosphorylated tau were investigated.

METHODS

bFGF-loaded liposome carriers were intranasally administered to rats. The neuroprotective effects of bFGF were assessed in a PD model induced by 6-hydroxydopamine (6-OHDA) in vivo and in vitro. The phosphorylation of tau was measured, and the PI3K/Akt-GSK3β signaling pathway was investigated.

RESULTS

Our study demonstrated that liposomes markedly assisted in the delivery of bFGF to the striatum and substantia nigra of rats and enhanced the neuroprotective effects of bFGF on dopaminergic neurons. bFGF treatment significantly ameliorated the behavioral deficits induced by 6-OHDA, rescued the loss of tyrosine hydroxylase-positive neurons and increased the number of Nissl bodies. bFGF reduced the phosphorylation of tau and GSK3β and increased the phosphorylation of PI3K/Akt.

CONCLUSION

Liposomes markedly assisted in the delivery of bFGF to the brain and enhanced the neuroprotective effects of bFGF by inhibiting the phosphorylation of tau. bFGF down-regulated the phosphorylation of tau by increasing the phosphorylation of GSK3β via the PI3K/Akt signaling pathway. These findings provide a new vision of bFGF as a potential therapy for PD.

Protection conferred by virus-like particle vaccines against respiratory syncytial virus infection in mice by intranasal vaccination

Respiratory syncytial virus (RSV) is a major pathogen in infants and the elderly, causing pneumonia and bronchiolitis. Despite decades of research, to date there is still no approved RSV vaccine available. In this study, we developed RSV virus-like particle (VLP) vaccines containing an RSV fusion (F) and/or attachment (G) protein with Newcastle disease virus (NDV) as the platform. The VLPs were expressed in a baculovirus system and purified by sucrose gradient centrifugation. BALB/c mice immunized intranasally (i.n.) with rNDV/RSV/F plus rNDV/RSV/G developed robust humoral, mucosal RSV-specific antibodies and cellular immune responses. Furthermore, rNDV/RSV/F plus rNDV/RSV/G provided better protection than did rNDV/RSV/F or rNDV/RSV/G alone, as shown by an obvious decrease in viral replication together with alleviation of histopathological changes in the lungs of the challenged mice. Our data demonstrate that the intranasal vaccination of combined RSV virus-like particle vaccine candidates has great potential for protection against RSV infection.

HDAC6: physiological function and its selective inhibitors for cancer treatment

Acetylation and deacetylation of histones are important in regulating gene expression and play a key role in modification of gene transcription. Specific HDACs isoforms can be regarded as a target for cancer therapy avoiding side-effects, HDAC6 with a unique physiological function and structure has become a hot issue recently. The unique isoform HDAC6 is involved in tumorigenesis, development and metastasis through tubulin, HSP90, invasin and ubiquitin-protein. Here we review the structure elements, biological function, and recent selective inhibitors of HDAC6, and study the structure-activity and structure-selectivity relationship.

The selection rule of graphene in a composite magnetic field

The generalized tight-binding model with exact diagonalization method is developed to calculate the optical properties of monolayer graphene in the presence of composite magnetic fields. The ratio of the uniform magnetic field and the modulated one accounts for a strong influence on the structure, number, intensity and frequency of absorption peaks, and thus the extra selection rules that are subsequently induced can be explained. When the modulated field increases, each symmetric peak, under a uniform magnetic field, splits into a pair of asymmetric peaks with lower intensities. The threshold absorption frequency exhibits an obvious evolution in terms of a redshift. These absorption peaks obey the same selection rule that is followed by Landau level transitions. Moreover, at a sufficiently strong modulation strength, the extra peaks in the absorption spectrum might arise from different selection rules.

[Establishment of a new rabbit model of ischemic cerebral infarction by autologous clot embolism]

OBJECTIVE

To establish a convenient method for preparing rabbit models of ischemic cerebral infarction using autologous clot embolism.

METHODS

Ischemic cerebral infarction was induced in rabbits by embolizing the middle cerebral artery using autologous clot emboli. Clinical and histological observations were carried out to evaluate the validity of the animal model.

RESULTS

Hemiplegia of different severities was observed in the rabbits after the operation. TTC and HE staining of the brain sections confirmed ischemic cerebral infarction 6 h after obstructing the middle cerebral artery with the autologous clot emboli.

CONCLUSION

Embolizing the middle cerebral artery using the autologous emboli is convenient to induce focal ischemic cerebral infarction in rabbits. This model has practical value in the study on the mechanism of ischemic cerebrovascular disease and in developing new strategies for prevention and treatment of the relevant diseases in human.

Clinical and radiographic spectrum of septic pulmonary embolism

AIMS

To review the clinical presentation, radiographic findings, and outcome of therapy in children with septic pulmonary embolism.

METHODS

Retrospective analysis of patients in a tertiary paediatric facility in northern Taiwan.

RESULTS

Ten children were identified with septic pulmonary emboli in a four year retrospective chart review between 1998 and 2001. Seven were immunocompetent, two were premature infants, one had beta thalassemia major. Seven had community acquired staphylococcal infections and bacteraemia, of which six were methicillin resistant Staphylococus aureus (MRSA) isolates. Five had soft tissue infections, two bone infections, one suppurative otitis media, one catheter related infection, and one unknown foci of infection. Multiple and bilateral nodular pulmonary parenchymal lesions were common on plain chest radiographs, but chest computed tomography scans showed the additional findings of a "vessel sign" and central cavitations, confirming the existence of septic pulmonary embolism.

CONCLUSIONS

Community acquired MRSA infections occurred in seven patients with septic pulmonary embolism but without predisposing high risk factors. Critically ill children with skin, soft tissue, or bone infections, when associated with septic pulmonary embolism in an area with a high rate of MRSA, should be empirically treated with glycopeptides (such as vancomycin or teicoplanin) before susceptibility results are known, in order to minimise morbidity and avoid mortality.

Cultural value similarities and differences among Asian American ethnic groups

Using data on 570 Chinese, Filipino, Korean, and Japanese American college students from 3 previous studies (1 published [B. S. K. Kim, D. R. Atkinson, & P. H. Yang, 1999] and 2 unpublished [B. S. K. Kim, 1999; E. C. Wong, B. S. K. Kim, N. W. S. Zane, I. J. Kim, & J. S. Huang, 1999]), the authors subjected 22 items constituting 6 value dimensions of the Asian Values Scale (AVS; B. S. K. Kim et al., 1999) to the following structural equation modeling procedures: confirmatory factor analysis, factorial invariance analysis, and structured means analysis. The results of confirmatory factor analysis provided support for a hierarchical factor model when this model was compared with 2 competing models. The results of factorial invariance analysis indicated that the meanings of the factors within the hierarchical model were conceived similarly among the 4 Asian American ethnic groups. On the basis of these results, a structured means analysis was conducted, revealing similarities and differences between the ethnic groups' adherence to 6 cultural value dimensions. Implications regarding psychological services for these Asian Americans are discussed, and suggestions for future research are offered.

Design and development of the European American values scale for Asian Americans

Existing instruments for measuring Asian American acculturation emphasize behavior acculturation to the exclusion of value acculturation. Most are based on the assumption that acquisition of European American behavior occurs simultaneously with the loss of Asian behavior. With the advent of the Asian Values Scale (AVS; B.S.K. Kim, D.R. Atkinson, & P.H. Yang, 1999), it is now possible to assess adherence to Asian cultural values. This article describes the development of a scale that can be used to measure Asian American adherence to European American values. The current scale, combined with the AVS, can be used to independently measure Asian American acculturation to European American values and enculturation in Asian values.

Fluconazole therapy in neonatal candidemia

We reviewed 62 episodes (from 59 infants) of neonatal candidemia that occurred between January 1994 and June 1999. Except 5 term babies, all infants were premature (median gestational age [GA], 30 weeks) and birth weight was less than 2,500 g (median, 1,300 g). Most infants had reported risk factors and other neonatal problems. The age at onset of candidemia ranged from 15 to 173 days with a median of 34 days. In addition to catheter removal, all but one infants received antifungal agents and candidemia was eradicated subsequently in 46 episodes (75%). Eighteen infants with 19 episodes ever received fluconazole therapy. Fluconazole was administered as the first line agent in 6 episodes and successfully cleared candidemia in 5 episodes. Fluconazole was used as an alternative agent in an additional 13 episodes after amphotericin B (am B) +/- flucytosine were given for a period without a satisfactory result and eradication of candidemia was achieved in 8 episodes subsequently. All 18 infants tolerated fluconazole well and no withdrawal was required on account of its adverse effect. In contrast, am B alone was administered as the first line agent in 55 episodes and successfully cleared candidemia in 32 episodes (58%). This retrospective analysis suggests that fluconazole appears to be safe in neonates and can be used as an alternative agent in treating neonatal candidemia. A large-scaled prospective study may be needed.

Study of plasma endothelin-1 concentrations in Taiwanese neonates with respiratory distress

BACKGROUND

Endothelin-1 (ET-1) is a novel and potent endothelium-derived vasoconstriction peptide present in human plasma. In this study, plasma ET-1 concentrations were determined and their physiological significance was evaluated in Taiwanese neonates with respiratory distress.

METHODS

Sixty newborn infants consisting of 22 with respiratory distress syndrome (RDS), 13 with transient tachypnea of newborn (TTNB), 4 with meconium aspiration syndrome, 10 healthy preterm and 11 healthy full-term infants were included for plasma ET-1 determination. Plasma ET-1 levels were measured by enzyme immunoassay at the of age of 1 day. For those who were diagnosed with RDS, plasma ET-1 concentrations were scheduled for evaluation at the ages of 1, 2, 3, 7, 14, 28, and 35 days as long as oxygen was being used.

RESULTS

On the first day of life, there was no significant difference in plasma ET-1 concentrations between healthy preterm and term infants (3.92 +/- 0.88 vs. 3.56 +/- 1.98 pg/mL, p = 0.606). However, plasma ET-1 concentrations of infants with RDS were significantly higher than those with TTNB (6.46 +/- 0.58 vs. 3.77 +/- 1.29 pg/mL, p < 0.001). In RDS infants, plasma ET-1 concentrations showed no significant difference between those who developed bronchopulmonary dysplasia (BPD, N = 4) and those who recovered (non-BPD, n = 18) (7.84 +/- 1.85 vs. 5.81 +/- 2.76 pg/mL, p = 0.242).

CONCLUSION

Plasma ET-1 concentrations were similar in preterm and term infants. ET-1 concentrations were higher in infants with RDS than in infants with TTNB, which suggests that plasma ET-1 levels can be useful in the differential diagnosis. However, the plasma ET-1 concentrations can not be a predictor for BPD.

Persistent pulmonary hypertension of the newborn: experience in a single institution

Persistent pulmonary hypertension of the newborn (PPHN) remains one of the most challenging situations in the neonatal intensive care unit, and it is associated with high mortality and morbidity. The optimal treatment for PPHN is controversial. We report our 9-year experience in the management of PPHN through a retrospective review of 29 neonates with persistent pulmonary hypertension. The diagnosis of PPHN is made by echocardiography and/or preductal and postductal oxygen tension difference. The treatment modalities include supportive medical care, vasodilator therapy, mechanical ventilation and correction of underlying conditions. The wide diversity of etiologies of PPHN, the complications of vasodilator therapy, the management of assisted ventilation, the mortality and the morbidity are evaluated. There are 29 patients enrolled in this study, including 18 male and 11 female babies. Twenty-two patients (72%) are referred from other hospitals. The mean birth body weight is 2707 +/- 693 grams (range: 1450-4100 grams) and the mean gestational age is 37.1 +/- 3.1 weeks (range: 31-41 weeks). The underlying clinical conditions include meconium aspiration syndrome (n = 8), perinatal asphyxia (n = 7), respiratory distress syndrome (n = 5), sepsis and/or pneumonia (n = 4), congenital diaphragmatic hernia (n = 3) and idiopathic persistent fetal circulation (n = 2). In addition to supportive medical care and correction of underlying clinical conditions, most of the patients receive vasodilator therapy (Tolazoline) and nonhyperventilation respirator management. The overall mortality rate is 27.6% (8/29). The duration on ventilator therapy in the survival group (9.3 +/- 8.6 days) is not significantly different from in the mortality group (6.0 +/- 7.1 days) (p = 0.13). There is also no statistically significant difference between these two groups both in the maximal alveolar-arterial oxygen tension difference (594 +/- 53 mmHg and 613 +/- 37 mmHg, p = 0.145) and in the maximal oxygenation index (49.7 +/- 29.6 and 61.1 +/- 36.9, p = 0.172) before vasodilator therapy. However, twenty-four hours after treatment, these two parameters change significantly with the former changes to 426 +/- 198 mmHg and 643 +/- 7 mmHg, respectively (p < 0.001), and the latter changes to 21.6 +/- 15.8 and 82.3 +/- 54.8, respectively (p < 0.001). Skin rash, gastrointestinal hemorrhage, hypotension and hyponatremia are the most common complications of Tolazoline therapy. Eight patients have pulmonary complications including pneumothorax (n = 5) and pulmonary interstitial emphysema (n = 3). Two patients develop chronic lung disease. Three patients have neurodevelopmental handicap. In conclusion, we achieve a survival rate of nearly 75% in PPHN mainly with the administration of Tolazoline therapy and the nonhyperventilation respirator approach. Further well-controlled and multicenter studies with newer treatment modalities are crucial for the improvement of survival of PPHN in Taiwan.

Hirschsprung's disease presenting with diffuse intestinal pneumatosis in a neonate

In the neonate, pneumatosis intestinalis is almost always associated with necrotizing enterocolitis. The manifestation of diffuse intestinal pneumatosis in Hirschsprung's disease has been reported rarely. It may occur as a result of Hirschsprung's disease complicated with enterocolitis. We report a two-day-old female baby born at term with the problems of failure to pass meconium, progressive abdominal distension and bile stained vomiting. There was an early roentgenographic presentation of pneumatosis intestinalis which might have led to a diagnosis of necrotizing enterocolitis. However, the intestinal pneumatosis resolved within 48 hours. After anorectal manometry and contrast enema examination, an ileostomy was performed at the age of 23 days, and multiple biopsies of intestine showed aganglionosis up to the ileum at the level of 85 cm above the ileocecal valve. Unfortunately, the patient developed short bowel syndrome after operation and died suddenly after an accidental choking at the age of three months. This case suggests that Hirschsprung's disease may have an unusual early roentgenographic presentation with diffuse intestinal pneumatosis in the first few days of life. Anorectal manometries and suction biopsies are crucial for further diagnosis.

Treatment and outcome of congenital diaphragmatic hernia

BACKGROUND AND PURPOSE

Congenital diaphragmatic hernia (CDH) is a challenging condition and is associated with a high mortality rate; optimal therapy remains unclear. This retrospective study describes the clinical characteristics of treatment and outcome in 48 infants with CDH.

METHODS

Twenty-eight male (58%) and 20 female (42%) infants with CDH were treated from 1987 through 1998. The goals of the ventilator strategy were permissive hypercapnea (PaCO2 < or = 55 mm Hg) and avoidance of hyperventilation. Infants were initially ventilated with an intermittent mandatory rate of 40 to 60 per minute, peak inspiratory pressure of 20 to 25 cm H2O, and positive end-expiratory pressure of 5 cm H2O. High-frequency positive pressure ventilation was used if hypoxemia or severe hypercapnea (PaCO2 > 60 mm Hg) occurred. Most infants underwent repair after 3 days of age and only four infants underwent early repair within 24 hours of birth. A prophylactic chest tube was placed in the ipsilateral hemithorax postoperatively in all patients treated before 1996. The severity of respiratory distress was estimated by alveolar-arterial oxygen difference, oxygenation index, and alveolar-arterial ratio.

RESULTS

Forty-six patients presented with Bochdalek CDH, and two with Morgangni CDH. Antenatal diagnosis was made in 10 cases. Respiratory distress was the major manifestation and usually occurred immediately after birth. Six cases were diagnosed several months after birth and presented mainly with gastrointestinal symptoms. Eleven patients died before surgery and 37 patients underwent surgical repair. Two infants died postoperatively because of congestive heart failure and tension pneumothorax, respectively. The overall mortality rate was 27%. The major causes of mortality were severe respiratory failure, persistent pulmonary hypertension, pneumothorax, and associated anomalies.

CONCLUSION

Nearly 75% of patients in this series survived. This suggests that noninvasive respiratory care combined with delayed surgery may be an acceptable strategy for the treatment of CDH, and can be used in most medical institutions without equipment for extracorporeal membrane oxygenation therapy.

Diagnostic pitfalls in congenital right diaphragmatic hernia

Congenital diaphragmatic hernia (CDH) is a rare disease of newborns. Right-sided diaphragmatic hernia is even rarer. The clinical and radiological presentations, which are well documented in left-sided diaphragmatic hernia, are variable in right-sided diaphragmatic hernia. This makes the diagnosis of right-sided diaphragmatic hernia more difficult. During a 12-year period, seven cases of right-sided diaphragmatic hernia were collected from a single institution. Their presentations and clinical courses have been reviewed. Low prenatal diagnostic rate, various roentgenogram expressions after birth, and absence of specific clinical presentations were noted. These expressions may become pitfalls in diagnosis and lead to inappropriate treatment. From our experience in these 7 cases and a brief literature review, we try to emphasize the characteristics and the diagnostic pitfalls of this disease. In conclusion, right-sided congenital diaphragmatic hernia has a variable clinical spectrum with high mortality and morbidity. Careful evaluation of the clinical presentations, ultrasonography and chest films is mandatory for precise diagnosis.

Candidaemia in special care nurseries: comparison of albicans and parapsilosis infection

OBJECTIVES

Candidaemia caused by Candida parapsilosis (CP) is being increasingly reported among infants in neonatal intensive care units (NICU). To assess relative severity, clinical manifestations of candidaemia caused by C. albicans (CA) and CP in a NICU were compared.

METHODS

Between January 1994 and July 1997, episodes of candidaemia occurring among infants hospitalized in the NICU were identified in a children's hospital. The demographic characteristics, associated risk factors, clinical manifestations and outcome of the infants with CP fungaemia were collected and compared with those of the infants with CA fungaemia.

RESULTS

Twenty-four episodes caused by CA and 22 episodes caused by CP were included in this study. No significant differences were found between the two groups for gestational age, birth weight, male gender, post-natal age at onset of candidaemia, frequency of antecedent neonatal events, prior duration of antibiotic therapy and hyperalimentation, as well as presence of central venous catheter (CVC). Infants with CA fungaemia were significantly more likely than those with CP fungaemia to present with hypoxaemia, bradycardia and respiratory distress requiring intubation, and have a longer prior duration of indwelling CVC and a higher dissemination rate. The eradication rate of candidaemia and overall case fatality rate were comparable in both groups. but CP fungaemia did not appear to cause acute lethal events.

CONCLUSION

The presenting signs of CP fungaemia are relatively not so severe, but CP fungaemia, which is relatively difficult to eradicate, increases the morbidity and mortality of the infants.

Vallecular cyst: an uncommon cause of stridor in newborn infants

Vallecular cyst, a rare but generally benign lesion in the larynx, may cause stridor and even life-threatening airway obstruction in early infancy. We retrospectively studied 14 cases of newborn infants with vallecular cyst. There was no gender predilection and most cases were full-term and appropriate for gestational age. The clinical presentations included stridor, chest wall retraction, feeding difficulties and failure to thrive. Laryngomalacia was the most common associated anomaly. Flexible laryngoscopy was sufficient for diagnosing the vallecular cyst and larygmalacia. Maintenance of airway patency, nutritional support, and de-roofing of the cyst were the mainstays of management.

CONCLUSION

Vallecular cyst should be included in the differential diagnosis of stridor in newborn infants. Respiratory and feeding difficulties in these patients can be dramatically improved after appropriate surgical removal of the cyst.

Neonatal necrotizing fasciitis: a report of three cases and review of the literature

OBJECTIVE

Necrotizing fasciitis (NF) is a predominantly adult disorder, with bacterial infection of the soft tissue. In children, it is relatively rare and has a fulminant course with a high mortality rate. In the neonate, most cases of NF are attributable to secondary infection of omphalitis, balanitis, mammitis, postoperative complications, and fetal monitoring. The objective of this communication is to report 3 cases of neonatal NF and provide a literature review of this disorder.

RESULTS

This review yielded 66 cases of neonatal NF. Only 3 cases were premature. There was no sex predilection and the condition rarely recurred. Several underlying conditions were identified that might have contributed to the development of neonatal NF. These included omphalitis in 47, mammitis in 5, balanitis in 4, fetal scalp monitoring in 2, necrotizing enterocolitis, immunodeficiency, bullous impetigo, and maternal mastitis in 1 patient each. The most common site of the initial involvement was the abdominal wall (n = 53), followed by the thorax (n = 7), back (n = 2), scalp (n = 2), and extremity (n = 2). The initial skin presentation ranged from minimal rash to erythema, edema, induration or cellulitis. The lesions subsequently spread rapidly. The overlying skin might later develop a violaceous discoloration, peau d'orange appearance, bullae, or necrosis. Crepitus was uncommon. Fever and tachycardia were frequent but not uniformly present. The leukocyte count of the peripheral blood was usually elevated with a shift to the left. Thrombocytopenia was noted in half of the cases. Hypocalcemia was rarely reported. Of the 53 wound cultures available for bacteriologic evaluation, 39 were polymicrobial, 13 were monomicrobial, and 1 was sterile. Blood culture was positive in only 20 cases (50%). Treatment modalities included the use of antibiotics, supportive care, surgical debridement, and drainage of the affected fascial planes. Two of the 6 cases who received hyperbaric oxygen therapy died. The overall mortality rate was 59% (39/66). In 12 cases, skin grafting was required because of poor granulation formation or large postoperative skin defects among the survivors.

CONCLUSION

Neonatal NF is an uncommon but often fatal bacterial infection of the skin, subcutaneous fat, superficial fascia, and deep fascia. It is characterized by marked tissue edema, rapid spread of inflammation, and signs of systemic toxicity. The wound cultures are predominantly polymicrobial and the location of initial involvement depends on the underlying etiologic factor. High index of suspicion, prompt aggressive surgery, appropriate antibiotics, and supportive care are the mainstays of management in the newborn infant with NF.

A survey on the treatment strategy of patent ductus arteriosus in very low-birth-weight infants

This study is a retrospective analysis of the clinical data of 67 very low birth weight infants (VLBWI) with symptomatic patent ductus arteriosus (PDA); all were admitted to four neonatal intensive care units (NICU) from January 1, 1996 through December 31, 1996. The mean gestational age was 27.9 +/- 2.4 weeks, the mean birth weight was 1078 +/- 193 g. Fifty-six infants (83.6%) had RDS, and 53 infants (79%) received artificial surfactant. The NICU at a regional hospital used CVD score > or =3 as the sole criteria and the remaining three NICUs used color Doppler echocardiogram to confirm a symptomatic PDA and to treat it; sometimes LA/AO > or = 1.3 was used as the criteria for indomethacin treatment. Two of these three hospitals sometimes used the pulsed Doppler echocardiogram as well as color Doppler examination as the treatment criteria. Seven infants (10.5%) had contraindication for indomethacin treatment; four of them closed after conservative treatment, and another three were subjected to surgical ligation. Of the remaining 60 infants, 3 were treated with oral indomethacin and 57 were treated with intravenous indomethacin. The mean age when initial treatment given was 3.8 +/- 1.5 days (range, 8 hours approximately 20 days). Among them 10 (16.7%) were within 24 hours after birth, 25 (41.7%) were between 24 and 48 hours, and 25 (41.7%) were beyond 48 hours. The dosage of indomethacin was 0.2 mg/kg per dose intravenously every 12 to 24 hours for three doses as a full course, if not contraindicated. The mean dose of indomethacin was 2.8 +/- 1.5; 10 infants (16.7%) received 1 dose, 15 (25%) received 2 doses, 27 (45%) received 3 doses, 3 (5%) received 4 doses and 5 (8.3%) received 6 doses. Among them, 51 infants (85%) PDA closed (including 2 treated with oral indomethacin), 9 (15%) failed to close and 6 of them received surgical ligation (including 1 treated with oral indomethacin). The complications associated with indomethacin treatment were hypoglycemia (52%), decreased urine output (42%) and gastrointestinal hemorrhage (32%). The infants with RDS had an earlier mean age of initial treatment than non-RDS infants (3.3 +/- 2.5 vs. 7.6 +/- 5.6 days; p < 0.05), and also had a higher closure rate (89% vs. 57%; p < 0.05). There was a closure rate of 85% in this multicenter retrospective analysis. Even though the infants received only one or two doses, they still had a good chance of ductal closure (21/25, 84%). To minimize the complications associated with indomethacin treatment in VLBWI, the protocol of indomethacin treatment should be re-evaluated.

Rickets of premature infants induced by calcium deficiency. A case report

Rickets of prematurity is not uncommon in neonatal intensive care units. Nutritional rickets in childhood is usually caused by vitamin D deficiency, but the rickets of prematurity is mainly attributable to calcium and phosphorus deficiencies. We present a premature infant with sequelae of necrotizing enterocolitis who needed prolonged administration of total parenteral nutrition (TPN), and who sustained ricketic fracture. After high calcium-fortified TPN supplementation the fracture healed well, and serum alkaline phosphatase dropped. This finding shows (1) serum calcium and phosphorus levels are of predictive value regarding rickets, (2) regular follow-ups of alkaline phosphatase levels combined with radiography in high-risk groups of premature infants are good tools for monitoring rickets, and (3) prolonged TPN administration needs to contain higher calcium and phosphorus concentrations in prematurity than in childhood.

Morbidity of survivors of neonatal respiratory distress syndrome under four years of age

This study evaluates the morbidity of neonatal respiratory distress syndrome (RDS) survivors in the Taiwan area. Sixty-three survivors of RDS, without surfactant therapy, were followed from January 1984 to December 1994. Comparisons between RDS survivors and 102 premature controls demonstrated that allergic rhinitis and hyperreactive airway (HRA) were adversely affected in RDS infants and children, especially in patients with chronic lung disease (CLD). It is interesting that a high incidence of otitis media and hypothyroidism was not found in this study, even though these have been reported elsewhere as more frequent among RDS survivors than among control subjects.

Neonatal meningococcal meningitis: report of two cases

Two neonates with meningococcal meningitis and meningococcemia are reported. The two, aged 28 and 16 days, respectively, presented similar symptoms of fever, poor appetite and poor activity. Both blood and cerebrospinal fluid cultures of each patient grew Neisseria meningitidis. The isolated bacteria were sensitive to penicillin, and both patients recovered completely after penicillin treatment for 22 and 15 days, respectively. In the antibiotic era, only 22 cases of neonatal meningococcal meningitis have been reported in the English literature. Among these reports, at least 7 patients survived without sequelae; 6 of those were treated with different combinations of antibiotics, including penicillin, for variable durations of 7-14 days. Therefore, effective antibiotic therapy for 14 days should be adequate in the treatment of uncomplicated neonatal meningococcal meningitis and meningococcemia.

Neonatal renal venous thrombosis--a case report describing serial sonographic changes

Neonatal renal venous thrombosis (NRVT) is a serious complication of newborns. Ultrasound is most useful in detecting NRVT. However, there is no detailed description of the evolution of ultrasound finding in NRVT. Here we report a patient with NRVT with complete ultrasound follow-up. Perivascular streaks were first seen at 3 days of age with a diffusely enlarged and echogenic right kidney. Echolucency then gradually appeared over the medulla area with shrinking renal size. Concomitant loss of renal function was evidenced by dimercaptosuccinic acid scan. The kidney became contracted at the age of 1 year. Since the pathognomonic perivascular streaks were present for only a few days, early ultrasound scanning should be performed for every newborn suspected of having NRVT.

Bacteremia due to non-typhi Salmonella: analysis of 64 cases and review

Within a 5-year period, 64 patients were hospitalized at the Chang Gung Memorial Hospital of Keelung (Taiwan) with bacteremia due to non-typhi Salmonella. Fifteen were < 24 weeks of age, 17 were between 6 months and 5 years of age, and 32 were > 18 years of age. An analysis of these patients revealed several significant differences between pediatric and adult patients. For instance, 87.5% of the adults but none of the children were debilitated because of severe underlying disease. Mortality was high (40.6%) among adults, but no deaths were observed among the children. Diarrhea occurred significantly more frequently among children (68.7%) than among adults (15.6%), while the contrary was observed in regard to chills, which occurred in 31% of adults and none of the children. It is concluded that bacteremia due to non-typhi Salmonella presents with different clinical features in adults than it does in children; furthermore, in adults the disease can be considered life-threatening, but in children it is associated with a favorable prognosis.

Pyogenic sacroiliitis in children: report of three cases

We report three children who were treated for pyogenic infection of the sacroiliac joint. The disease, usually present in late childhood or adolescence, is uncommon and difficult to assess so that the diagnosis is usually delayed. The three patients were two boys and one girl, aged 14, 15 and 12 years, respectively. A detailed history and physical examination are very important for establishment of the diagnosis. All the three cases presented with typical clinical triad of fever, limping gait and buttock pain. Pelvis compression maneuver, which directly stresses the sacroiliac joint, may aggravate the joint pain and suggest this diagnosis. On physical examination, this test is positive in all our cases. Nuclear scintigraphy is useful for localization of early lesions. For detecting abscess formation, magnetic resonance imaging was performed in two cases and computed tomography in one. In one of the patients, computed tomography failed to demonstrate an iliopsoas abscess formation, which was proved by magnetic resonance imaging later. Staphylococcus aureus was isolated from blood in all three patients. Prompt antibiotic therapy reduces complication and operation is rarely needed. With rapid and appropriate medical treatment, all our patients recovered without an sequelae.

[Cytomegalovirus infection in neonate--report of two cases]

The cytomegalovirus (CMV) is an abiquitous agent that infects almost all human beings at some time during their lives. In developing area of the world, 90% or more of the population is infected during childhood. However, in developed countries the infection is acquired at a lower rate. In neonates, CMV infection can be divided into congenital and perinatal infection. Congenital CMV infection is the result of transplacental transmission, CMV can be transmitted to the fetus following reactivation as well as primary infection during pregnancy. The incidence of congenital infection is 0.2% to 2.2%. Symptomatic congenital CMV infection is more likely to be the result of primary as opposed to reactive CMV infection during pregnancy. The clinical manifestations of symptomatic CMV infection are hepatosplenomegaly, microcephaly, jaundice, petechiae, small for gestation age, periventricular calcification and chorioretinitis. Mortality may be as high as 30% among the most severely affected infants. In the survivors, about 90% will develop mild to severe handicaps. Perinatal CMV infection can be acquired from exposure to virus in the maternal genital tract at delivery, breast milk, or through blood transfusion. In premature infants who require prolonged and intensive medical care, blood transfusions are an important iatrogenic cause of CMV infection. Transfusion-acquired perinatal CMV infection can cause significant morbidity and mortality, particularly in premature infants with a birth weight of less than 1250 gm born to CMV-seronegative mothers. So CMV acquisition can be prevented either by providing these infants blood products from seronegative donors or by using frozen deglycerolized red blood cells. Two cases of neonatal CMV infection are reported, one with congenital infection, the other with perinatal infection.

Effect of cross cylinder power on cylinder axis sensitivity

Astigmatic errors (0.50 D to 1.50 D in 0.25 D steps) were induced in each of 5 subjects, and cylinder axis thresholds were assessed from 12 reversals of a 2.5 degrees stepsize staircase for 0.50 D and 1.00 D cross cylinders (CC). Equivalent power thresholds were 0.077 D (0.05 SD) for the 0.50 D CC and 0.104 D (0.05 SD) for the 1.00 D CC. Findings are significantly different from predictions of a "linear" blur detection model, but are consistent with a model assuming constant blur thresholds and power-dependent distortion thresholds. Our results support the use of minimal CC power in refining cylinder axis.

Correlation of IR spectroscopic, heat capacity, diamagnetic susceptibility and enzymatic measurements on lysozyme powder

The interaction between protein and water is of fundamental importance for processes ranging from protein folding and enzymatic activity to anhydrobiosis. In this letter we bring together results from diverse types of measurements to give a unified picture of the hydration process for lysozyme. The data come principally from experiments with protein films and powders. The principal aim is to examine the relationship between the sites of water interaction, the extent of coverage, and the enzymatic activity, thus providing a better understanding of the relationship between water and enzyme dynamics.

Protein--water interactions. Heat capacity of the lysozyme--water system

Calorimetric measurements of the heat capacity of the lysozyme-water system have been carried out over the full range of system composition at 25 degrees C. The partial specific heat capacity of the protein in dilute solution is 1.483 +/- 0.009 J K-1 g-1. The heat capacity of the dry protein is 1.26 +/- 0.01 J K-1 g-1. The system heat capacity responds linearly to change in composition from dilute solution to 0.38 g of water per g of protein (h) and is an irregular function at lower water content. The break in the heat capacity function at 0.38 h defines the amount of water needed to develop the equilibrium solution properties of lysozyme as being 300 molecules of water/protein molecule, just sufficient for monolayer coverage. The heat capacity behavior at low water content describes three hydration regions. The most tightly bound water (0-0.07 h), probably principally bound to charged groups, is characterized by a partial specific heat capacity of 2.3 J K-1 g-1, a value close to that for ice. A heat of reaction associated with proton redistribution is reflected in the heat capacity function for the low-hydration region. Between 0.07 and 0.25 h the heat capacity increases strongly, which is understood to reflect the growth of patches of water covering polar and adjacent nonpolar portions of the protein surface. The hydration shell is completed by condensation of solvent over the weak-interacting portions of the surface, in a process displaying a transition heat.