Validation of a Modified Early Warning Score (Mews) in Emergency Department Observation Ward Patients

Objective

The Modified Early Warning Score (MEWS) is a simple physiological scoring system, which can easily be applied at the bedside. The ability of MEWS to identify patients at risk of deterioration in a busy ward was investigated.

Method

In a prospective cohort study, we applied MEWS to patients admitted to the 16-bed emergency department observation ward (EDOW) of a tertiary teaching hospital.

Results

Data on 427 consecutive EDOW admissions were collected from 7 June to 4 July 2004. Main outcome measures were death, intensive care unit (ICU) admission and inpatient hospital admission. Scores of > 4 were associated with increased risk of death (OR 54.4, 95% CI = 4.7–633.7), ICU admission (OR 12.7, 95% CI = 1.1–147.3) and hospital admission (OR 9.5, 95% CI = 3.3–27.9).

Conclusion

MEWS is suitable for bedside application in an EDOW setting and may help identify patients at risk of deterioration who require increased levels of care as hospital inpatients and in ICU. Where experienced staff is not available to closely monitor patients in an EDOW, the use of the MEWS system may aid close monitoring and identification of high-risk patients.

The anti-hypertensive effect of Danshen (Salvia miltiorrhiza) and Gegen (Pueraria lobata) formula in rats and its underlying mechanisms of vasorelaxation

ETHNOPHARMACOLOGICAL RELEVANCE

Radix Salviae miltiorrhizae (Danshen) and Radix Puerariae lobatae (Gegen) have long been used in traditional Chinese Medicine and serve as the principal herbs in treating cardiovascular disease.

AIMS OF THE STUDY

In the present study, an aqueous extract comprising Danshen and Gegen in the ratio of 7:3 (DG) was investigated for its anti-hypertension in vivo and vasodilative activities ex vivo.

MATERIALS AND METHODS

The anti-hypertensive effect of DG extract was investigated in spontaneously hypertensive rat (SHR) by measuring systolic blood pressure (SBP). Oral administration of DG extract was started at age of 6 weeks and 14 weeks for the preventive and therapeutic studies, respectively. Blood pressure was measured by tail-cuff method biweekly for 12 weeks. The ex vivo vasodilative activities of DG extract, its dependency on endothelium and the involvement of nitric oxide, prostacyclin and potassium channels were investigated using isolated rat aorta ring in organ bath.

RESULTS

For in vivo study, systolic blood pressure was significantly reduced in DG extract-treated groups (90.2 and 300 mg/kg) as compared with the SHR control in both preventive and therapeutic studies. However, DG extract was unable to suppress or delay the onset of hypertension in the preventive study. For ex vivo study, the results showed that DG extract induced a concentration-dependent relaxation in aorta and persisted response was observed with the removal of endothelium. Besides, pretreatment with a non-selective potassium channel inhibitor tetraethylammonium (TEA) also significantly inhibited DG extract-induced vasodilation. Further investigations on specific potassium channel blockers revealed that ATP-sensitive potassium (K(ATP)) channel inhibitor glibenclamide, inward rectifier potassium (Kir) inhibitor barium chloride and voltage-dependent potassium (K(v)) channel inhibitor 4-aminopyridine, but not BK(Ca) channel inhibitor iberiotoxin, exerted significant inhibition on DG extract-induced vasodilation.

CONCLUSIONS

The results of in vivo SHR animal model suggested that DG aqueous extract possessed blood pressure lowering effect on both pre- and post-hypertensive rats, which could be explained by its endothelium-independent vasodilation via the opening of K(ATP), Kir and K(v) channels.

The expression of frizzled-3 receptor in colorectal cancer and colorectal adenoma

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Background: Wnt signaling is well known for its role in colorectal cancer (CRC) formation through transcriptional activities of nuclear β-catenin. Although activation of Wnt signaling depends on specific Wnt/Frizzled receptors (FZD) combinations, the specificity of the interaction and the role of FZD in that particular interaction are still unknown. Among the 10 Wnt receptors of the FZD protein family, FZD-3 is involved in neurodevelopmental abnormalities and gastric cancer carcinogenesis. However, the expression of FZD-3 in CRC is not clear. Therefore in this study, we examined the expression of FZD-3 in CRC cell lines and CRC patient tissues with various pathological stages. The information obtained will be important for us to understand the role of FZD-3 in the development of CRC.

Methods: FZD-3 mRNA expression was studied in CRC metastatic SW620, primary SW480 and normal CCD18co cell lines using quantitative real-time polymerase chain reaction with primers and a Taqman minor grove binder probe (Applied Biosystems, Foster City, USA). Moreover, paraffin-embedded specimens of 40 CRC patient tissues, 25 colorectal adenoma (CA) tissues were retrieved from the Department of Pathology, Queen Elizabeth Hospital, Hong Kong Special Administrative Region for FZD-3 immunostaining using an anti-FZD-3 antibody (Catalog no: MAB1001, R&D systems Inc., Minneapolis, USA) in an automatic Ventana Benchmark XT immunostainer (Ventana Medical Systems Inc., Tucson, USA).

Results: FZD-3 mRNA was up-regulated in metastatic SW620 cell line (fold-change: 622) and in primary SW480 cell line (fold-change: 820) when compared to that in normal CCD18co cell line. Furthermore, immunostaining showed that FZD-3 protein was expressed in 100% (40/40) of CRC specimens and 84% (21/25) of CA specimens. Detailed analysis showed that FZD-3 protein was significantly up-regulated in CRC, CA when compared to their adjacent normal colorectal epithelial tissues (p < 0.0005, Wilcoxon matched pairs test).

Conclusions: This study provided evidence that FZD-3 is involved in CRC carcinogenesis and it is a potential therapeutic target in CRC.

No significant financial relationships to disclose.

Differential requirement for individual sarcoglycans and dystrophin in the assembly and function of the dystrophin-glycoprotein complex

Sarcoglycan is a multimeric, integral membrane glycoprotein complex that associates with dystrophin. Mutations in individual sarcoglycan subunits have been identified in inherited forms of muscular dystrophy. To evaluate the contributions of sarcoglycan and dystrophin to muscle membrane stability and muscular dystrophy, we compared muscle lacking specific sarcoglycans or dystrophin. Here we report that mice lacking (delta)-sarcoglycan developed muscular dystrophy and cardiomyopathy similar to mice lacking (gamma)-sarcoglycan. However, unlike muscle lacking (gamma)-sarcoglycan, (delta)-sarcoglycan-deficient muscle was sensitive to eccentric contraction-induced disruption of the plasma membrane. In the absence of (delta)-sarcoglycan, (alpha)-, (beta)- and (gamma)-sarcoglycan were undetectable, while dystrophin was expressed at normal levels. In contrast, without (gamma)-sarcoglycan, reduced levels of (alpha)-, (beta)- and (delta)-sarcoglycan were expressed, glycosylated and formed a complex with each other. Thus, the elimination of (gamma)- and (delta)-sarcoglycan had different molecular consequences for the assembly and function of the dystrophin-glycoprotein complex. Furthermore, these molecular differences were associated with different mechanical consequences for the muscle plasma membrane. Through this in vivo analysis, a model for sarcoglycan assembly is proposed.

Who should follow up lung cancer patients after operation?

BACKGROUND

It is unclear whether follow-up by a thoracic surgeon after lung cancer resection alters survival.

METHODS

The charts of 245 early stage (< or = IIB) non-small cell lung cancer patients, diagnosed between 1988 and 1995, were reviewed. Follow-up data were complete to January 1, 1997, in 96.3% (236 of 245) of cases.

RESULTS

Ninety of the 111 recurrences were detected before discharge from the thoracic clinic. Despite clinic follow-up, 66.7% (60 of 90) were identified by the family physician, and only 28.9% (26 of 90) by the surgeon. The remaining 4.4% (4 of 90) were detected by other physicians. Ninety-six percent (25 of 26) surgeon-detected recurrences had suspicious clinical or chest radiographic findings, compared with 92% for family physician-detected recurrences (55 of 60; not significant). The cost per recurrence detected by surgeons was Can $4,367. A 75% cost savings could ensure if patients were followed up by their family physician. There was no 5-year survival benefit for patients whose recurrence was detected by the surgeon.

CONCLUSIONS

Long-term follow-up after limited-stage non-small cell lung cancer resection could possibly be performed by a family physician alone without compromising overall survival, and with significant cost savings.

Muscle degeneration without mechanical injury in sarcoglycan deficiency

In humans, mutations in the genes encoding components of the dystrophin-glycoprotein complex cause muscular dystrophy. Specifically, primary mutations in the genes encoding alpha-, beta-, gamma-, and delta-sarcoglycan have been identified in humans with limb-girdle muscular dystrophy. Mice lacking gamma-sarcoglycan develop progressive muscular dystrophy similar to human muscular dystrophy. Without gamma-sarcoglycan, beta- and delta-sarcoglycan are unstable at the muscle membrane and alpha-sarcoglycan is severely reduced. The expression and localization of dystrophin, dystroglycan, and laminin-alpha2, a mechanical link between the actin cytoskeleton and the extracellular matrix, appears unaffected by the loss of sarcoglycan. We assessed the functional integrity of this mechanical link and found that isolated muscles lacking gamma-sarcoglycan showed normal resistance to mechanical strain induced by eccentric muscle contraction. Sarcoglycan-deficient muscles also showed normal peak isometric and tetanic force generation. Furthermore, there was no evidence for contraction-induced injury in mice lacking gamma-sarcoglycan that were subjected to an extended, rigorous exercise regimen. These data demonstrate that mechanical weakness and contraction-induced muscle injury are not required for muscle degeneration and the dystrophic process. Thus, a nonmechanical mechanism, perhaps involving some unknown signaling function, likely is responsible for muscular dystrophy where sarcoglycan is deficient.

Occurrence of a common lipopolysaccharide antigen in standard and clinical strains of Pseudomonas aeruginosa

The lipopolysaccharide (LPS) of Pseudomonas aeruginosa PAO1 contains two species of O polysaccharide termed A and B bands. The high-molecular-weight B-band LPS determines the O specificity of the bacterium, while the antigenically distinct A-band LPS consists of only shorter-chain polysaccharides. Seven hybridomas secreting A-band-specific monoclonal antibodies were produced and used to study the LPS of standard and clinical strains. Although A-band antibodies did not agglutinate any of the serotype strains presently in the International Antigenic Typing Scheme, Western immunoblots revealed that 11 of the 17 serotype strains possessed A-band LPS. In a group of 250 clinical isolates from patients with cystic fibrosis, 170 (68%) had A-band LPS on the basis of agglutination tests, but in silver-stained gels all were shown to be deficient in O-antigen-containing B band. Investigation of serial isolates from a single patient revealed a pattern of antigenic variation. During the course of the infection, serotypeable isolates became nontypeable, and the O antigen was replaced with A band as the major LPS antigen. These results suggest that A-band LPS may be the major LPS antigen in nontypeable clinical isolates and a common antigen among other P. aeruginosa strains.

Production of monoclonal antibodies against serotype strains of Pseudomonas aeruginosa

A panel of 22 monoclonal antibodies against 8 of the 17 International Antigenic Typing Scheme (IATS) serotypes of Pseudomonas aeruginosa was produced. The antibodies were characterized for cross-reactivities, isotypes, titers, and epitope specificities. The results complemented those of our previous study and marked the completion of a set of monoclonal antibodies for serotyping P. aeruginosa.

Visualization of Pseudomonas aeruginosa O antigens by using a protein A-dextran-colloidal gold conjugate with both immunoglobulin G and immunoglobulin M monoclonal antibodies

Two lipopolysaccharide O-antigen-specific monoclonal antibodies, MA1-8 (an immunoglobulin G1 [IgG1]) and MF15-4 (an IgM), were used to localize the O antigen of the lipopolysaccharide of Pseudomonas aeruginosa PAO1. A protein A-dextran-gold conjugate with an average particle diameter of 12.5 nm was used to label bacterial cells treated with MA1-8, while a second antibody (goat anti-mouse IgM) was required before the same probe could interact with cells treated with the IgM antibody MF15-4. Both antibodies resulted in exclusive labeling of the surface of P. aeruginosa PAO1 but not that of an isogenic O-antigen-lacking rough mutant. When the monoclonal antibodies became attached to the cell surface of P. aeruginosa PAO1, resulting in an even coating, the foldings and other topographic details could not be discerned by negative staining. In thin sections of monoclonal-antibody-treated bacteria, a 20- and a 30- to 40-nm thick amorphous layer was observed around the outside of the outer membrane when MA1-8 (IgG) and MF15-4 (IgM) plus goat anti-mouse IgM antibodies were used, respectively. This amorphous layer presumably resulted from the stabilization of the lipopolysaccharide structure by the monoclonal antibodies which prevented the long O-antigen chains from collapsing owing to dehydration.

Production and characterization of monoclonal antibodies against serotype strains of Pseudomonas aeruginosa

Monoclonal antibodies against 12 of the 17 IATS serotype strains of Pseudomonas aeruginosa were produced. Eighty-seven hybridoma clones were isolated, and the antibodies secreted were found to be reactive with both Formalin-fixed whole cells and purified lipopolysaccharide of homologous strains in enzyme-linked immunosorbent assays. Among these monoclonal antibodies, the predominant antibody class was immunoglobulin M (IgM) (76%), although antibodies of the IgG2a and IgG3 isotypes were also produced. The monoclonal antibodies could further be divided into two groups based on their ability to agglutinate whole cells of homologous strains. The agglutinating monoclonal antibodies were found to immunoblot with the O side chains of homologous lipopolysaccharide, while the nonagglutinating monoclonal antibodies were found to be reactive with outer membrane protein-associated lipopolysaccharide. The applicability of monoclonal antibodies for serotyping was examined, and several antibodies were found to agglutinate whole cells and immunoblot with the O antigen of corresponding serotypes of clinical isolates from cystic fibrosis patients. In conclusion, a set of monoclonal antibodies against the IATS serotype strains of P. aeruginosa have been produced. These antibodies represent a bank of invaluable immunological reagents which may have application in serotyping, epitope mapping, lipopolysaccharide structural determination, and studies of protection against P. aeruginosa.