The hygiene hypothesis, first proposed in 1989, suggested that reduced exposure to infections in early life leads to allergic diseases by the defects in the establishment of immune tolerance. Although many studies provided evidence that some exposure conditions, including family size, antibiotics, probiotics, and viral or bacterial infections, are strongly related to the prevalence of allergic diseases, thereby supporting the hygiene hypothesis, some evidence does not provide acceptable results for the hygiene hypothesis. Further, most studies have focused on patients with asthma or atopic dermatitis, not allergic rhinitis. In this review, we summarize the recent studies for and against the ‘hygiene hypothesis’ and identify causal association with the prevalence of allergic rhinitis.

Background: Atherogenic dyslipidemia, which is frequently associated with type 2 diabetes (T2D) and insulin resistance, contributes to the development of vascular complications. Statin therapy is the primary approach to dyslipidemia management in T2D, however, the role of non-statin therapy remains unclear. Ezetimibe reduces cholesterol burden by inhibiting intestinal cholesterol absorption. Fibrates lower triglyceride levels and increase high-density lipoprotein cholesterol (HDL-C) levels via peroxisome proliferator- activated receptor alpha agonism. Therefore, when combined, these drugs effectively lower non-HDL-C levels. Despite this, few clinical trials have specifically targeted non-HDL-C, and the efficacy of triple combination therapies, including statins, ezetimibe, and fibrates, has yet to be determined. Methods: This is a multicenter, prospective, randomized, open-label, active-comparator controlled trial involving 3,958 eligible participants with T2D, cardiovascular risk factors, and elevated non-HDL-C (≥100 mg/dL). Participants, already on moderate-intensity statins, will be randomly assigned to either Ezefeno (ezetimibe/fenofibrate) addition or statin dose-escalation. The primary end point is the development of a composite of major adverse cardiovascular and diabetic microvascular events over 48 months. Conclusion This trial aims to assess whether combining statins, ezetimibe, and fenofibrate is as effective as, or possibly superior to, statin monotherapy intensification in lowering cardiovascular and microvascular disease risk for patients with T2D. This could propose a novel therapeutic approach for managing dyslipidemia in T2D.

BACKGROUND: This study investigated the overall status of diabetes control and screening for diabetic microvascular complications in patients with type 2 diabetes mellitus attending primary care clinics in Korea. METHODS: In this cross-sectional observational study, 191 primary care clinics were randomly selected across Korea from 2015 to 2016. In total, 3,227 subjects were enrolled in the study. RESULTS: The patients followed at the primary care clinics were relatively young, with a mean age of 61.4±11.7 years, and had a relatively short duration of diabetes (mean duration, 7.6±6.5 years). Approximately 14% of subjects had diabetic microvascular complications. However, the patients treated at the primary care clinics had suboptimal control of hemoglobin A1c levels, blood pressure, and serum lipid levels, along with a metabolic target achievement rate of 5.9% according to the Korean Diabetes Association guidelines. The screening rates for diabetic nephropathy, retinopathy, and neuropathy within the past 12 months were 28.4%, 23.3%, and 13.3%, respectively. CONCLUSION: The overall status of diabetes management, including the frequency of screening for microvascular complications, was suboptimal in the primary care clinics. More efforts should be made and more resources need to be allocated for primary care physicians to promote adequate healthcare delivery, which would result in stricter diabetes control and improved management of diabetic complications.
Blood Pressure ; Delivery of Health Care ; Diabetes Complications ; Diabetes Mellitus, Type 2 ; Diabetic Nephropathies ; Humans ; Korea ; Mass Screening ; Observational Study ; Physicians, Primary Care ; Primary Health Care ; Tertiary Care Centers

BACKGROUND: A 9-year-old male showed severe defects in midface structures, which resulted in maxillary hypoplasia, ocular hypertelorism, relative mandibular prognathism, and syndactyly. He had been diagnosed as having Apert syndrome and received a surgery of frontal calvaria distraction osteotomy to treat the steep forehead at 6 months old, and a surgery of digital separation to treat severe syndactyly of both hands at 6 years old. Nevertheless, he still showed a turribrachycephalic cranial profile with proptosis, a horizontal groove above supraorbital ridge, and a short nose with bulbous tip. METHODS: Fundamental aberrant growth may be associated with the cranial base structure in radiological observation. RESULTS: The Apert syndrome patient had a shorter and thinner nasal septum in panthomogram, PA view, and Waters’ view; shorter zygomatico-maxillary width (83.5 mm) in Waters’ view; shorter length between the sella and nasion (63.7 mm) on cephalogram; and bigger zygomatic axis angle of the cranial base (118.2°) in basal cranial view than a normal 9-year-old male (94.8 mm, 72.5 mm, 98.1°, respectively). On the other hand, the Apert syndrome patient showed interdigitating calcification of coronal suture similar to that of a normal 30-year-old male in a skull PA view. CONCLUSION: Taken together, the Apert syndrome patient, 9 years old, showed retarded growth of the anterior cranial base affecting severe midface hypoplasia, which resulted in a hypoplastic nasal septum axis, retruded zygomatic axes, and retarded growth of the maxilla and palate even after frontal calvaria distraction osteotomy 8 years ago. Therefore, it was suggested that the severe midface hypoplasia and dysostotic facial profile of the present Apert syndrome case are closely relevant to the aberrant growth of the anterior cranial base supporting the whole oro-facial and forebrain development.
Acrocephalosyndactylia ; Adult ; Child ; Exophthalmos ; Forehead ; Hand ; Humans ; Hypertelorism ; Male ; Maxilla ; Nasal Septum ; Nose ; Osteotomy ; Palate ; Prognathism ; Prosencephalon ; Skull ; Skull Base ; Sutures ; Syndactyly

PURPOSE: Rhinitis is a nasal inflammatory disease in children and adolescents. However, little is known about the phenotypes and characteristics of allergic rhinitis (AR) in Korean children and adolescents. The objective of this study was to analyze the symptoms and comorbidities of rhinitis, to compare AR to non-allergic rhinitis (NAR), and to reveal the phenotypes and features of AR in a Korean pediatric population. METHODS: Patients under 18 years of age with rhinitis symptoms were recruited from January 2013 to January 2015 by pediatric allergists. We analyzed symptoms, phenotypes, comorbidities, and allergen sensitization in this cross-sectional, multicenter study. RESULTS: Medical records were collected from 11 hospitals. The AR group has 641 (68.3%) patients, with 63.2% of boys and 7.5 (±3.4) years of mean age. The NAR group has 136 (14.5%) patients, with 55.1% of boys and 5.5 (±2.9) years of mean age. Moderate-severe persistent AR affected 41.2% of AR patients. Nasal obstruction was more common in NAR patients (P<0.050), whereas AR patients sneezed more (P<0.050) and more commonly had conjunctivitis, asthma, and otitis media (P<0.050). Sinusitis was the most common comorbidity in both groups. Allergen sensitization was caused by house dust mites (HDMs) (90.2%), pollen (38.7%), and animal dander (24.8%) in AR patients. Pollen and animal dander sensitization significantly increased age-dependently (P<0.050), but 91.9% of AR patients were already sensitized to HDMs before 5 years old. CONCLUSIONS: Our study revealed that AR was more prevalent than NAR and that 41.2% of AR presented with moderate-severe disease in Korean pediatric populations. Sinusitis was the most common comorbidity, and sleep disturbance was associated with the severity of rhinitis. The majority of AR patients were sensitized to HDMs in preschool ages. Further studies, including nationwide and longitudinal data, will help understand the relationship between these diseases.
Adolescent* ; Animals ; Asthma ; Child* ; Comorbidity* ; Conjunctivitis ; Dander ; Humans ; Medical Records ; Nasal Obstruction ; Otitis Media ; Phenotype* ; Pollen ; Pyroglyphidae ; Rhinitis* ; Rhinitis, Allergic ; Sinusitis

PURPOSE: To evaluate the effects of hydrogen peroxide pretreatment and heat activation of silane on the shear bond strength of fiber-reinforced composite posts to resin cement. MATERIALS AND METHODS: The specimens were prepared to evaluate the bond strength of epoxy resin-based fiber posts (D.T. Light-Post) to dual-curing resin cement (RelyX U200). The specimens were divided into four groups (n=18) according to different surface treatments: group 1, no treatment; group 2, silanization; group 3, silanization after hydrogen peroxide etching; group 4, silanization with warm drying at 80℃ after hydrogen peroxide etching. After storage of the specimens in distilled water at 37℃ for 24 hours, the shear bond strength (in MPa) between the fiber post and resin cement was measured using a universal testing machine. The fractured surface of the fiber post was examined using scanning electron microscopy. Data were analyzed using one-way ANOVA and post-hoc analysis with Tukey's HSD test (α=0.05). RESULTS: Silanization of the fiber post (Group 2) significantly increased the bond strength in comparison with the non treated control (Group 1) (P<.05). Heat drying after silanization also significantly increased the bond strength (Group 3 and 4) (P<.05). However, no effect was determined for hydrogen peroxide etching before applying silane agent (Group 2 and 3) (P>.05). CONCLUSION: Fiber post silanization and subsequent heat treatment (80℃) with warm air blower can be beneficial in clinical post cementation. However, hydrogen peroxide etching prior to silanization was not effective in this study.
Cementation ; Hot Temperature* ; Hydrogen Peroxide* ; Hydrogen* ; Microscopy, Electron, Scanning ; Resin Cements* ; Shear Strength ; Water

BACKGROUND: Prenatal tongue development may affect oral-craniofacial structures, but this muscular organ has rarely been investigated. METHODS: In order to document the physiology of prenatal tongue growth, we histologically examined the facial and cranial base structures of 56 embryos and 106 fetuses. RESULTS: In Streeter's stages 13-14 (fertilization age [FA], 28 to 32 days), the tongue protruded into the stomodeal cavity from the retrohyoid space to the cartilaginous mesenchyme of the primitive cranial base, and in Streeter's stage 15 (FA, 33 to 36 days), the tongue rapidly swelled and compressed the cranial base to initiate spheno-occipital synchondrosis and continued to swell laterally to occupy most of the stomodeal cavity in Streeter's stage 16-17 (FA, 37 to 43 days). In Streeter's stage 18-20 (FA, 44 to 51 days), the tongue was vertically positioned and filled the posterior nasopharyngeal space. As the growth of the mandible and maxilla advanced, the tongue was pulled down and protruded anteriorly to form the linguomandibular complex. Angulation between the anterior cranial base (ACB) and the posterior cranial base (PCB) was formed by the emerging tongue at FA 4 weeks and became constant at approximately 124degrees-126degrees from FA 6 weeks until birth, which was consistent with angulations measured on adult cephalograms. CONCLUSIONS: The early clockwise growth of the ACB to the maxillary plane became harmonious with the counter-clockwise growth of the PCB to the tongue axis during the early prenatal period. These observations suggest that human embryonic tongue growth affects ACB and PCB angulation, stimulates maxillary growth, and induces mandibular movement to achieve the essential functions of oral and maxillofacial structures.
Adult ; Axis, Cervical Vertebra ; Embryonic Structures* ; Fetus* ; Humans ; Mandible ; Maxilla ; Mesoderm ; Parturition ; Physiology ; Skull Base ; Tongue*

BACKGROUND: A1chieve(R) was a noninterventional study evaluating the clinical safety and efficacy of biphasic insulin aspart 30, insulin detemir, and insulin aspart. METHODS: Korean type 2 diabetes patients who have not been treated with the study insulin or have started it within 4 weeks before enrollment were eligible for the study. The patient selection and the choice of regimen were at the discretion of the physician. The safety and efficacy information was collected from the subjects at baseline, week 12, and week 24. The number of serious adverse drug reactions (SADRs) was the primary endpoint. The changes of clinical diabetic markers at week 12 and/or at week 24 compared to baseline were the secondary endpoints. RESULTS: Out of 4,058 exposed patients, 3,003 completed the study. During the study period, three SADRs were reported in three patients (0.1%). No major hypoglycemic episodes were observed and the rate of minor hypoglycemic episodes marginally decreased during 24 weeks (from 2.77 to 2.42 events per patient-year). The overall quality of life score improved (from 66.7+/-15.9 to 72.5+/-13.5) while the mean body weight was slightly increased (0.6+/-3.0 kg). The 24-week reductions in glycated hemoglobin, fasting plasma glucose and postprandial plasma glucose were 1.6%+/-2.2%, 2.5+/-4.7 mmol/L, and 4.0+/-6.4 mmol/L, respectively. CONCLUSION: The studied regimens showed improvements in glycemic control with low incidence of SADRs, including no incidence of major hypoglycemic episodes in Korean patients with type 2 diabetes.
Biphasic Insulins ; Body Weight ; Diabetes Mellitus, Type 2 ; Drug Toxicity ; Fasting ; Glucose ; Hemoglobins ; Humans ; Incidence ; Insulin ; Insulin Aspart ; Insulin, Isophane ; Insulin, Long-Acting ; Patient Selection ; Plasma ; Quality of Life ; Republic of Korea ; Treatment Outcome ; Insulin Detemir

PURPOSE: To determine the quantitative parameters of breast MRI that predict tumor invasion in biopsy-proven DCIS. MATERIALS AND METHODS: From January 2009 to March 2010, 42 MRI examinations of 41 patients with biopsy-proven DCIS were included. The quantitative parameters, which include the initial percentage enhancement (E1), peak percentage enhancement (E(peak)), time to peak enhancement (TTP), signal enhancement ratio (SER), arterial enhancement fraction (AEF), apparent diffusion coefficient (ADC) value, long diameter and the volume of the lesion, were calculated as parameters that might predict invasion. Univariate and multivariate analyses were used to identify the parameters associated with invasion. RESULTS: Out of 42 lesions, 23 lesions were confirmed to be invasive ductal carcinoma (IDC) and 19 lesions were confirmed to be pure DCIS. Tumor size (p = 0.003; 6.5 +/- 3.2 cm vs. 3.6 +/- 2.6 cm, respectively) and SER (p = 0.036; 1.1 +/- 0.3 vs. 0.9 +/- 0.3, respectively) showed statistically significant high in IDC. In contrast, E1, Epeak, TTP, ADC, AEF and volume of the lesion were not statistically significant. Tumor size and SER had statistically significant associations with invasion, with an odds ratio of 1.04 and 22.93, respectively. CONCLUSION: Of quantitative parameters analyzed, SER and the long diameter of the lesion could be specific parameter for predicting invasion in the biopsy-proven DCIS.
Breast ; Carcinoma in Situ ; Carcinoma, Ductal ; Carcinoma, Intraductal, Noninfiltrating ; Diffusion ; Humans ; Lymphokines ; Magnetic Resonance Imaging ; Multivariate Analysis ; Odds Ratio ; Thymine Nucleotides