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Hepatitis B virus (HBV) infection is a major global health problem, and healthcare workers (HCWs) are at high risk for HBV infection. Current guidelines strongly recommend immunization and screening for high-risk groups.We evaluated immunization and screening for HBV vaccination, assessed post-vaccination immune status of HCW's and characterized potential risk factors associated with poor immune response.From January 2010 to December 2018, we retrospectively analyzed comprehensive health checkup data for a total of 303 HCWs who received an HBV vaccination. After vaccination, HBV surface antibody (anti-HBs) titers were collected and the distribution of immune response types was determined. Risk factors for poor immune responses were identified using logistic regression.A total of 213 HCWs were analyzed after exclusion based on the exclusion criteria. In total, 28 (13.2%) HCWs had anti-HBs titers100 mIU/mL (hyporesponsive/nonresponsive groups), and 185 (86.8%) had anti-HBs titers ≥100 mIU/mL (hyperresponsive group). Follow-up observations found that 75% (21/28) of the hyporesponsive/nonresponsive groups did not have increased anti-HBs titers or did not maintain an increased response. A multivariate analysis showed that HBV antibody titers at the time of employment were a significant risk factor (OR, 6.12; CI, 1.34-27.93; P = 0.019).More attention should be paid to groups that are hyporesponsive/nonresponsive after vaccination and to those with low anti-HBs titers at the beginning of employment. HCWs can be further protected from HBV if their results are discussed at postvaccination follow-ups.

Background Fluoroquinolones are a popular alternative to trimethoprim-sulfamethoxazole for Stenotrophomonas maltophilia infections. Objectives To compare the effects of fluoroquinolones and trimethoprim-sulfamethoxazole on mortality of S. maltophilia infections. Data sources PubMed and EMBASE. Study eligibility criteria Clinical studies reporting mortality outcomes of S. maltophilia infections. Participants Patients with clinical infections caused by S. maltophilia. Interventions Fluoroquinolone monotherapy in comparison with trimethoprim-sulfamethoxazole monotherapy. Methods Systematic review with meta-analysis technique. Results Seven retrospective cohort and seven case–control studies were included. Three cohort studies were designed to compare the two drugs, whereas others had other purposes. A total of 663 patients were identified, 332 of which were treated with trimethoprim-sulfamethoxazole (50.1%) and 331 with fluoroquinolones (49.9%). Three cohort studies were designed to compare the effect of the two drugs, whereas the others had other purposes. Levofloxacin was most frequently used among fluoroquinolones (187/331, 56.5%), followed by ciprofloxacin (114/331, 34.4%). The overall mortality rate was 29.6%. Using pooled ORs for the mortality of each study, fluoroquinolone treatment (OR 0.62, 95% CI 0.39–0.99) was associated with survival benefit over trimethoprim-sulfamethoxazole treatment, with low heterogeneity (I2 = 18%). Specific fluoroquinolones such as ciprofloxacin (OR 0.44, 95% CI 0.17–1.12) and levofloxacin (OR 0.78, 95% CI 0.48–1.26) did not show a significant difference in comparison with trimethoprim-sulfamethoxazole. In the sub-group analyses of adult and bacteraemic patients, significant differences in mortality were not observed between fluoroquinolones and trimethoprim-sulfamethoxazole. Conclusions Based on a meta-analysis of non-randomized studies, fluoroquinolones demonstrated comparable effects on mortality of S. maltophilia infection to trimethoprim-sulfamethoxazole, supporting the use of fluoroquinolones in clinical S. maltophilia infections. Although the pooled analysis of overall studies favoured fluoroquinolones over trimethoprim-sulfamethoxazole, the studies included were observational, and sub-group analyses of certain fluoroquinolone agents did not show statistical differences with trimethoprim-sulfamethoxazole. Randomized clinical studies are needed to address these issues.

BACKGROUND AND PURPOSE: Life-threatening bleeding in the head and neck requires urgent management. This study evaluated the angiographic findings related to head and neck bleeding and presents endovascular management techniques. MATERIAL AND METHODS: Sixty-one consecutive patients who presented with acute bleeding in the head and neck areas and subsequently underwent endovascular therapy between January 2002 and October 2012 were included in our study. We evaluated the angiographic findings, techniques, and results of endovascular management. RESULTS: Contrast leakage ( n = 10), pseudoaneurysm ( n = 20), or both ( n = 10) were the most common life-threatening angiographic findings (66%) and were the foci of immediate embolization or endoluminal vessel reconstruction. Seventeen patients (28%) had hypervascular staining of the tumor or mucosa, and 4 patients (6%) did not have any abnormal findings. The acute bleeding was successfully controlled by endovascular management according to the bleeding foci. Carotid arterial lesions, so-called “carotid blowout,” required reconstructive or deconstructive therapy. Bleeding of the external carotid artery required specific branch embolization by a combination of various embolic materials. No procedure-related complications occurred except in 1 patient who experienced acute infarction caused by thromboemboli from the covered stent. Seventeen patients (28%) were retreated due to rebleeding after the mean 20-month follow-up. CONCLUSIONS: Contrast leakage or a pseudoaneurysm or both seen on angiography are active bleeding foci and targets for therapy in patients with acute bleeding in the head and neck area. Despite different bleeding-control strategies according to vessel involvement, endovascular treatment is safe and effective for controlling hemorrhage.

BACKGROUND AND PURPOSE: Acute occlusion of the ICA is often associated with poor outcomes and severe neurologic deficits. This study was conducted to evaluate outcome of the occluded ICA and efficacy of recanalization under protective flow arrest. MATERIALS AND METHODS: Fifty consecutive patients who underwent endovascular treatment for acute ICA occlusion were identified from the prospectively collected data base. We assessed NIHSS(o), occlusion type (cardioembolism vs atherosclerosis), occlusion level (supraclinoid-terminal, petrocavernous, or bulb-cervical), recanalization degree (TICI), and efficacy of recanalization (protective flow arrest vs nonprotection) leading to better outcome. RESULTS: Successful recanalization (TICI ≥ 2) was obtained in 90% of patients and good recovery (mRS ≤ 2) in 60% of patients. Good outcome was related to National Institutes of Health Stroke Scale score on admission (P < .001), TICI (P < .007), occlusion type (P = .022), and occlusion level (P = .038). Poor initial patient status, less recanalization, cardioembolism, and supraclinoid-terminal occlusion were associated with poor prognosis. Application of protective flow arrest led to better outcome in the distal ICA segment than in the bulb-cervical segment. CONCLUSIONS: In addition to the initial patient status and successful recanalization, the occlusion level or type of the occluded ICA could affect clinical outcome. In this study, treatment benefits of protective flow arrest were accentuated in patients with ICA occlusion above the bulb-cervical segment.

SUMMARY: Vertebral artery recanalization in symptomatic stenosis/occlusion remains controversial, as no definite evidence exists regarding this topic. There are only a few reports regarding the feasibility and safety of recanalization in the first segment of the vertebral artery with atherosclerotic vertebral ostial occlusion. We report our experience treating first segment occlusion in 8 patients and present a balloon protection technique used to reduce the thromboembolic burden during the stent placement procedure. The outcome at 3 months showed an mRS ≤2 except for a patient with a poor initial status with basilar artery occlusion. Revascularization of a rather long first segment occlusion is technically feasible and can be safely performed by use of embolic protection methods.

In preparation for a clinical trial on the efficacy of Echinacea products with a pediatric population, a rational method for selection of test products was developed, based on phytochemical and bioassay evaluation. Ten currently available commercial products of Echinacea angustifolia (EA) or Echinacea purpurea (EP) were selected, and 3 bottles of each of 2 different lots were purchased for each product. Investigators were blinded to product identity before phytochemical analysis. Lot-to-lot variation was small, but product variation due to species and formulation was large. Products derived from ethanol extracts had low polysaccharide content and high levels of alkamides (EA), echinacoside (EA), cynarin (EA), cichoric acid (EP), and caftaric acid (EP). These products possessed high antiviral activities that differed between EA and EP products, but limited immune activation properties. In contrast, products derived without ethanol extraction had higher polysaccharide levels, but low levels of other components. These aqueous compounds showed immunostimulant activity as measured in a mouse macrophage model and a somewhat different antiviral profile. The choice of Echinacea product for clinical trial must therefore consider the impact of immune enhancement, the specific viral infection targeted, and the potential to reduce symptoms via antiinflammatory activity. Product selection may also depend on whether the intent of the trial is prophylaxis or treatment.

To investigate the role of BRCA1 and BRCA2 mutations in Korean patients with sporadic breast cancer, 793 breast cancer patients were analyzed by denaturing high performance liquid chromatography and direct sequencing. The 793 breast cancer patients enrolled in this study had no family history of affected first- or second-degree relatives with breast and/or ovarian cancer. Seventy-nine different sequence variations were identified, of which 34 were novel. Fifteen deleterious mutations were detected in 20 out of 793 patients (2.5%): 11 frameshift mutations and 4 nonsense mutations (seven in BRCA1 and eight in BRCA2), and no recurrent or founder mutations were observed in BRCA mutation screening. However, three mutations (K467X, 3972delTGAG, and R2494X in BRCA2) were identified in other studies of the Korean population. Of 793 patients, the clinicopathological information was obtained in 135 patients, who included 20 deleterious mutation-positive and 115 deleterious mutation-negative groups. The median age at diagnosis, histologic type, histologic grade and T stage did not show statistically significant difference between these two groups. BRCA-mutation-associated tumors showed lower estrogen receptor, progesterone receptor, and HER-2/neu but higher p53 expression. Although poor prognostic features were noted in BRCA-associated tumors, we did not find statistically significant differences. The present study will be helpful in the evaluation of the need for the genetic screening of germline BRCA mutations and reliable genetic counseling for sporadic breast cancer patients.

Summary Background: Recently, echinacea has regained popularity as one of the treatments chosen most commonly by consumers with the expectation that it will reduce the severity and duration of the common cold. However, the results from a limited number of clinical trials for this application have thus far been inconclusive. This incongruity may be the result of investigators utilizing poorly standardized echinacea products, likely devoid of sufficient quantities of active constituents necessary to exert a definitive clinical effect. Therefore, a formulation containing alkamides, cichoric acid, and polysaccharides at concentrations of 0·25, 2·5, and 25 mg/mL, respectively, was prepared from freshly harvested Echinacea purpurea plants (commercially available as Echinilin, Natural Factors Nutritional Products, Inc., Vancouver, BC, Canada). The objective of this study was to test the efficacy of this highly standardized formulation in reducing the severity and duration of symptoms of a naturally acquired common cold. Methods: In a randomized, double-blind, placebo-controlled trial, 282 subjects aged 18–65 years with a history of two or more colds in the previous year, but otherwise in good health, were recruited. The subjects were randomized to receive either echinacea or placebo. They were instructed to start the echinacea or placebo at the onset of the first symptom related to a cold, consuming 10 doses the first day and four doses per day on subsequent days for 7 days. Severity of symptoms (10-point scale: 0, minimum; 9, maximum) and dosing were recorded daily. A nurse examined the subjects on the mornings of days 3 and 8 of their cold. Results: A total of 128 subjects contracted a common cold (59 echinacea, 69 placebo). The total daily symptom scores were found to be 23·1% lower in the echinacea group than in placebo in those who followed all elements of the study protocol (P

Aims: To investigate changes in the bacterial population and the safety of the biofilm at the end of the drinking water distribution system in Seoul (Korea), selective media and bacterial community analyses were applied to a semi-pilot galvanized iron pipe (GIP) model. Methods and Results: No total coliforms or faecal streptococci were detected on m-Endo or m-Enterococcus agar. No Salmonella spp. and Shigella spp. were detected on bismuth sulphite agar or Hektoen enteric agar, respectively. The latter two media detected coliforms, where m-Endo was negative. Biofilm formation started within 1 week (ca 104 CFU cm−2) and exceeded 105 CFU cm−2 within 6 weeks. Although the fatty acid methyl ester analysis revealed dynamic changes in bacterial composition, Micrococcus, Bacillus, and Pseudomonas spp. were persistent members of the biofilm community. Micrococcus spp. was detected most frequently and in high numbers. Conclusions: Coliforms and Enterococcus species can be recovered from biofilms in water distribution systems. Significance and Impact of the Study: This study illustrates the role of biofilms in the chronic deterioration of the water-distribution system in Seoul (Korea).

Expression of alkaline phosphatase(ALP)activity represents a key event during the differentiation processes of osteoblasts, and the level of ALP activity has been routinely used as a relative measure of differentiation stages of osteoblasts. In human osteoblasts, we showed that vitamin D3 analogue, 1,25(OH)2D3, had a stimulatory effect on ALP activity after 3 days, compared with control. The treatment of PD098059, an ERK MAP Kinase inhibitor, had a reducing effect on ALP activity, a differentiation marker in 1,25(OH)2D3-treated primary human osteoblasts. However, SB203580, a potent p38 MAP Kinase inhibitor, had no effect on the differentiation in this system. This indicates that ERK, not p38, is directly related to 1,25(OH)2D3-stimulated ALP activity in primary human osteoblasts. These results also show that the vitamin D3 analogue stimulates ERK1 activation in primary human osteoblasts. This finding provides one of signaling pathways for differentiation in primary human osteoblasts.

Background: The purpose of the present study was to describe the various imaging features of primary malignant fibrous histiocytoma (MFH) of the liver, a rare tumor of mesenchymal origin. Methods: Sonography (n= 5), computed tomography (CT; n= 5), magnetic resonance (MR) imaging (n= 2), and hepatic arteriography (n= 3) in five patients who underwent partial hepatectomy for tumor resection were retrospectively reviewed and correlated with pathologic findings. Results: All tumors were clearly demarcated from surrounding hepatic parenchyma in sectional imaging with (n= 2) or without (n= 3) a fibrous capsule, which was pathologically verified. Internal architecture of abundant fibrosis, myxoid degeneration, and/or hemorrhagic necrosis reflected the sonographic, CT and MR imaging findings. Marginal tumor staining without definite tumor vasculature was the main feature of hepatic arteriography. There was no intratumoral calcification. All three tumors involving the right lobe of the liver invaded the right hemidiaphragm. Conclusion: Although there were no unique findings of primary hepatic MFH, a combined interpretation of various imaging modalities may elucidate the malignant nature of the tumor.

Cancer Stem Cells (CSCs) from tumors of different phenotypes possess a marked capacity for proliferation, self-renewal, and differentiation. They also play a critical role in cancer recurrence. Although CSC has been regarded as a new target for cancer therapy, the fundamental questions in the CSC study have not been resolved mainly due to the lack of proper CSC markers. To find new CSC markers for oral squamous cell carcinoma (OSCC), we cultured the primary tumor cells from OSCC patients the regular culture condition and the sphere-forming culture condition to enrich primary tumor cells and potential CSCs. We compared gene expression profiles between sphere-forming and non-forming cells, thus identifying that 23 membrane protein-coding genes were over-expressed in the sphere-forming cells. Among them, 8 belonged to the solute carrier (SLC) protein family. H⁺-myo-inositol transporter SLC2A13 and monocarbohydrate transporter SLC16A6 genes that were consistently increased in the sphere-forming cells in the primary cultures of OSCC samples. Confocal microscopy revealed that SLC2A13-expressing cells were embedded in the limited areas of tumor tissue as a cluster, while SLC16A6 was uniformly detected in hyperplastic epithelium. Moreover, SLC2A13 an expression was induced in human breast adenocarcinoma MCF7 cells after serum starvation. Taken together, our results suggest that SLC2A13 can be a potential markers for CSC in various tumors.

Short interfering RNAs (siRNAs), namely siUL54-1 and siU54-2 targeting UL54 (DNA polymerase) gene, and siUL97-1 and siUL97-2 targeting UL97 (phosphotransferase) gene, were used to inhibit respective genes of Human cytomegalovirus (HCMV) and consequently the virus infection process in human foreskin fibroblast (HFF) cultures. The virus infection was monitored by cell morphology (CPE), levels of UL83 and IE86 mRNAs, and virus antigen. The results showed that siUL97-2 remarkably inhibited viral CPE while other siRNAs were less inhibitory. The siRNAs reduced the levels of UL83 mRNA but not that of IE86 mRNA; again, siUL97-2 was most inhibitory. Particularly, siUL97-2 reduced the UL83 mRNA level 14, 19, 203, and 37 times at 24, 48, 72, and 96 hrs post infection (p.i.), respectively. When tested for the effect on viral antigen by immunofluorescent assay (IFA), UL97-2 exerted a marked inhibition. These results demonstrate the effectiveness of siRNAs against experimental HCMV infection and indicate their therapeutic potential.

The purpose of this study was to investigate the possible association between estrogen receptor alpha (ERalpha) polymorphism and pain susceptibility in female symptomatic temporomandibular joint (TMJ) osteoarthritis (OA) patients. A patient group of 100 women, diagnosed as TMJ OA according to the research diagnostic criteria for temporomandibular disorders, were selected, and 74 women with no signs and symptoms of temporomandibular disorder were assigned to a control group. Pvu II and Xba I restriction fragment length polymorphisms were analyzed by direct haplotyping. The patient group was divided into three subgroups according to a visual analog scale (VAS): mild pain (0or=VAS4); moderate pain (4or=VAS7); severe pain (7or=VASor=10). Frequencies of genotypes and haplotypes in the patient and control groups were compared, and the association between pain intensity and copy numbers of PX haplotype were evaluated using the chi-square test. No significant differences in genotype and haplotype frequencies were observed between the patient and control groups (p.05). TMJ OA patients carrying the PX haplotype were found to have a significantly higher risk of moderate or severe pain compared to those without the PX haplotype, suggesting that ERalpha polymorphism may be associated with pain susceptibility in female TMJ OA patients.

The aim of this study was to investigate the possible influence of estrogen receptor alpha (ERalpha) polymorphism on the craniofacial skeleton in female patients suffering from symptomatic osteoarthritis (OA) of the temporomandibular joint (TMJ). The sample comprised 76 genetically unrelated Korean women diagnosed with OA by research diagnostic criteria for temporomandibular disorders (RDC-TMD). Direct haplotyping procedure was used to analyze the PvuII and XbaI RFLPs. Twelve cephalometric measurements were taken to evaluate the spatial position and dimensions of the mandible. Mann-Whitney's U-test was used to identify the potential differences in the cephalometric measurements between the subjects grouped according to their carrier status for Px haplotype. In addition, an association study was carried out using chi(2)-test to further examine the relationship between Px haplotype and the craniofacial morphology of the symptomatic OA patients. Female symptomatic TMJ OA patients carrying Px haplotype showed significantly smaller facial axis angle (P0.05) and mandibular body length (P0.05) than the non-carriers. The association between the presence of Px haplotype and short mandibular body length was also ascertained. This study suggests that ERa polymorphism contributes to the altered mandibular dimensions in female symptomatic TMJ OA patients. Further studies on the role of the genetic markers relevant to the craniofacial growth and adaptation are expected to broaden our understanding of determinants of the craniofacial morphology.

Immunotherapy based on the administration of the mycobacterium bacillus Calmette-Guerin has been successfully used in the treatment of in situ transitional cell bladder cancer, and may be applicable to the treatment of cutaneous malignant melanoma. Antigen 85A (Ag85A) and heat shock protein 65 kDa (hsp65) are major secreted proteins of Mycobacterium species and potent stimulators of cell-mediated immunity. This study evaluated the ability of Ag85A and hsp65 gene transfection to limit tumor growth by B16-F10 mouse melanoma cells. Immunoblotting confirmed protein expression and secretion by B16-F10 cells that were transiently transfected with plasmid DNA containing the Ag85A or hsp65 gene. Groups of syngeneic C57BL/6 mice were injected subcutaneously with 1x10(5) untransfected B16-F10 cells or B16-F10 cells transiently transfected with either empty vector or vector containing the Ag85A or hsp65 gene. Ag85A-expressing B16-F10 cells exhibited a dramatic 76% reduction (p0.05, Mann-Whitney U test) in tumor weight in comparison to empty vector controls at 14 days post-inoculation. In contrast, hsp65-transfected B16-F10 cells did not show any change in tumorigenicity. Decreased tumorigenicity by Ag85A-transfected B16-F10 cells was not due to a reduced ability of Ag85A-transfected B16-F10 cells to proliferate since both mock- and Ag85A-transfected B16-F10 cells showed increased in vitro proliferation in comparison to untransfected cells. Hematoxylin and eosin staining revealed that Ag85A-transfected B16-F10 tumors contained an inflammatory leukocyte infiltrate that was not present in hsp65-transfected tumors. Reduced tumor progression by Ag85A-transfected B16-F10 melanoma cells suggests that immunotherapy based on the transient induction of Ag85A expression may be an effective approach for the treatment of cutaneous malignant melanoma.

The alpha-helical antibiotic peptide (P18: KWKLFKKIPKFLHLAKKF-NH2) designed from the cecropin A(1-8)-magainin 2 (1-12) hybrid displayed strong bactericidal and tumoricidal activity without inducing hemolysis. The effect of the Pro9 residue at central position of P18 on cell selectivity was investigated by Pro9 --Leu or Pro9 --Ser substitution. Either substitution markedly reduced the antibacterial activity of P18 and increased hemolysis, although it did not significantly affect cytotoxicity against human transformed tumor and normal fibroblast cells. These results suggest that a proline kink in alpha-helical antibiotic peptide P18 serves as a hinge region to facilitate ion channel formation on bacterial cell membranes and thus plays an important role in providing high selectivity against bacterial cells. Furthermore, to investigate the structure-antibiotic activity relationships of P18, a series of N- or C-terminal deletion and substitution analogs of P18 were synthesized. The C-terminal region of P18 was related to its antibiotic activity and alpha-helical conformation on lipid membranes rather than N-terminal one. Higher alpha-helicity of the peptides was involved in the hemolytic and antitumor activity rather than antibacterial activity. Except for [L9]-P18 and [S9]-P18, all the designed peptides containing a Pro residue showed potent antibacterial activity, although they did not induce a cytolytic effect against human erythrocyte and normal fibroblast cells at the concentration required to kill bacteria. In particular, P18 and some analogs (N-1, N-2, N-3, N-3L and N-4L) with potent bactericidal and tumoricidal activity and little or no normal cell toxicity may serve as an attractive candidate for the development of novel anti-infective or antitumor agents.

To estimate the utility of thyroid transcription factor-1 (TTF-1) and the combined cytokeratin 7 (CK7) and 20 (CK20) immunoprofile as a marker for identifying the primary site of metastatic adenocarcinoma in effusions of the serous cavity.Formalin-fixed, paraffin-embedded cell block specimens of pleural and peritonealfluid diagnosed as metastatic adenocarcinomas with known sites of origin were used for TTF-1, CK7 and CK20 immunohistochemistry. The primary sites of these cases were lung (16 cases), ovary (15), stomach (9), colon (8) and breast (8) and were confirmed by radiologic and/or histologic evaluation.The lung adenocarcinomas showed TTF-1 positivity in 81% (13/16) of cases. All nonpulmonary adenocarcinomas lacked TTF-1 staining. The CK7-/CK20+ immunophenotype was seen in 63% of colonic adenocarcinomas and not seen in lung, ovary, stomach or breast adenocarcinomas. The CK7+/CK20- immunophenotype was seen in 100%, 88% and 87% of cases that originated in the lung, breast and ovary, respectively.TTF-7 immunostaining is useful in the differentiation between pulmonary and nonpulmonary origin of adenocarcinomas in malignant effusions. The combination of CK7-/CK20+ immunostaining is useful in identifying colon adenocarcinomas.

Necrotizing enterocolitis (NEC) can involve any site in the gastrointestinal tract and is a fatal complication of immunosuppression. To characterize NEC, clinical and radiological characteristics were analyzed. A total of 27 cases of NEC were identified from January 1993 to August 1998, and medical records were reviewed. NEC was diagnosed by clinical and radiological criteria, and other mimicking conditions were excluded. Of the NEC cases, 22 (81.5%) occurred in patients with underlying hematologic malignancy. All patients complained of abdominal pain and fever at the time of inclusion. Escherichia coli was the most common pathogen identified. The most common finding by computed tomography was single-layered diffuse bowel wall thickening with variable density. Other findings were ascites, fascial thickening, pneumatosis, and mesenteric lymphadenopathy. Of the patients, 25 were treated with antimicrobials with or without recombinant hematopoietic growth factors, and 2 were treated with surgery because of perforation and profound bleeding. Among the 12 patients who died, NEC was the direct cause of death in 7 patients. In conclusion, computed tomography is an effective tool for early diagnosis of NEC. Bowel rest, broad-spectrum antimicrobials, and recombinant hematopoietic growth factors are important aspects of treatment. Surgery should be reserved for complicated cases.

In the anaesthetic management of dystrophia myotonica, emphasis should be placed on the fact that it is a multisystem disease. Cardiac, respiratory, and endocrine functions should be considered of greater importance than the myotonic aspects of the disease. The management of a case is described, using pancuronium as the muscle relaxant. Plasma cholinesterase activity was measured and the need for further investigation is suggested.

Although mast cells are widely distributed in the body, their functions are poorly known. The elucidation of mast cell function is complicated by growing evidence that mast cells are heterogeneous. Recent studies of mast cell ontogeny suggest that microenvironmental stimuli control the phenotypic expression of parts of the genome leading to subtype differences in a common lineage. Mast cells influence cell proliferation, differentiation, and activation in a range of target cells, although until recently they were considered important only in immediate hypersensitivity. However, they function in delayed-type hypersensitivity, potentiate cytotoxicity of eosinophils and macrophages, and are cytotoxic for certain targets themselves. Mast cell mediators influence blood flow and vascular permeability and facilitate angiogenesis. Numerous mast cell mediators are immunoregulatory. In vitro experiments have begun to investigate the role of mast cells in fibrotic diseases. Further knowledge of mast cell heterogeneity will provide the basis for new therapies in inflammatory diseases of the intestine and other organs.