Causes and time-course of vertigo in an ear, nose, and throat clinic

The purpose of this study is to review etiologies and identify the time-course of vertigo presenting in an ear, nose, and throat clinic, and serve as a reference guide for other clinics. The study includes retrospective chart review in a tertiary care, university hospital. The patient data with reported ICD-10 codes as causes of vertigo between April 2005 and December 2007 were extracted from the database. At each visit, the main diagnosis as to etiology, characteristics of the vertigo, its time-course, and patient demographic data were recorded. Of 547 cases, 17 diagnoses were made in 73.9%. Diagnostic categories included peripheral vertigo 72.9%, central vertigo 0.8%, psychogenic cause 0.2%, and unknown 26.1%. Common causes of vertigo were benign paroxysmal positional vertigo (BPPV) 52.5%, Meniere’s disease 14.6%, and sudden idiopathic hearing loss 2.9%. Less common diagnoses were benign paroxysmal vertigo of childhood 0.7%, labyrinthitis 0.7%, and vestibular schwannoma 0.3%. Rare conditions were delayed endolymphatic hydrops, Ramsey Hunt syndrome, otosyphilis, vestibular neuritis, temporal bone fracture, post-concussion syndrome, cerebellar infarction, epilepsy, cervical vertigo, Streptococcus suis meningitis, and psychogenic vertigo. Ninety-nine cases who reported remission of vertigo during the study period had median onset of the remission at 4 weeks. In the ear, nose, and throat clinic at Chiang Mai University, a tertiary university hospital, peripheral vestibular disorders were the main etiology of vertigo. The three most common causes were BPPV, Meniere’s disease, and sudden idiopathic hearing loss. Half of the cases who returned for follow up had remitted symptoms within 4 weeks.     

Reduction in mother-to-child transmission of HIV in Thailand, 2001-2003: Results from population-based surveillance in six provinces

BACKGROUND: In 2000, Thailand implemented a national program to prevent mother-to-child HIV transmission (PMTCT). OBJECTIVE: To describe the effectiveness of the prevention of mother-to-child HIV transmission program in Thailand. DESIGN AND METHODS: A register of HIV-exposed children at birth was created with follow-up of infection status. The register included children born to HIV-infected women between 1 January 2001 and 31 December 2003 at 84 public health hospitals in six provinces of Thailand. The main outcome measure was HIV infection in children. RESULTS: A total of 2200 children born to HIV-infected mothers were registered. Of these mother-infant pairs, 2105 (95.7%) received some antiretroviral prophylaxis, including 1358 (61.7%) who received the complete short-course zidovudine regimen during pregnancy and labor for the mother and after birth for the infant, with or without other antiretrovirals. HIV infection outcome was determined for 1667 (75.8%) children, of whom 158 [9.5%, 95% confidence interval (CI), 8.1-11.0%] were infected. Transmission risk was 6.8% (95% CI 5.2-8.9%) among 761 mother-infant pairs that received the complete zidovudine regimen alone, and 3.9% (95% CI, 2.2-6.6%) among 361 mother-infant pairs that received the complete zidovudine regimen combined with other antiretrovirals, usually nevirapine. The overall transmission risk from this cohort, including all antiretroviral prophylaxis combinations, is estimated to be 10.2%. CONCLUSIONS: The Thai national PMTCT program is effective in reducing mother-to-child transmission risk from the historical risk of 18.9-24.2%. The addition of nevirapine to short-course zidovudine beginning in 2004 may further improve program effectiveness in Thailand.     

Carbohydrate Taste Is Associated with Food Intake and Body Mass in Healthy Australian Adults

Background: The taste of carbohydrates may drive their intake. Sensitivity to carbohydrate taste varies among individuals, thus, it is important to understand how differences in sensitivity influence eating behaviour and body mass. Objective: The aims of this study were to assess associations among carbohydrate taste sensitivity, habitual and acute food intake, and body mass; as well as assess the reliability of the carbohydrate detection threshold (DT) test within and across days. Methods: Carbohydrate DT was assessed six times across three sessions in 36 healthy adult participants (22 female) using a three-alternate forced choice methodology. Moreover, 24 h diet records were completed on the days prior to testing sessions, and food intake at a buffet lunch was collected following each session. Anthropometry was also measured. Linear mixed regression models were fitted. Results: The DT test required at least three measures within a given day for good reliability (ICC = 0.76), but a single measure had good reliability when compared at the same time across days (ICC = 0.54–0.86). Carbohydrate DT was associated with BMI (kg/m²: β = −0.38, p = 0.014), habitual carbohydrate intake (g: β = −41.8, p = 0.003) and energy intake (kJ: β = −1068, p = 0.019) from the 24-h diet records, as well as acute intake of a buffet lunch (food weight (g): β = −76.1, p = 0.008). Conclusions: This suggests that individuals who are more sensitive to carbohydrate are more likely to consume greater quantities of carbohydrates and energy, resulting in a greater body mass.     

Functional significance of the highly conserved Glu in the putative pore-forming helix 3 of the Bordetella pertussis haemolysin toxin

Adenylate cyclase-haemolysin toxin (CyaA) is a virulence factor secreted from the etiologic agent of whooping cough, Bordetella pertussis. Previously, the haemolysin or pore-forming domain (CyaA-PF) has been shown to cause cell lysis of sheep erythrocytes independently, and the predicted helix 3_(570−593) within the PF-hydrophobic stretch could be a pore-lining constituent. Here, a plausible involvement in haemolytic activity of polar or charged residues (Glu⁵⁷⁰, Gln⁵⁷⁴, Glu⁵⁸¹, Ser⁵⁸⁴ and Ser⁵⁸⁵) lining the hydrophilic side of CyaA-PF helix 3 was investigated via single-alanine substitutions. All the 126-kDa mutant proteins over-expressed in Escherichia coli were verified for toxin acylation as the results are corresponding to the wild-type toxin. When haemolytic activity of E. coli lysates containing soluble mutant proteins was tested against sheep erythrocytes, the importance of Glu⁵⁷⁰, which is highly conserved among the pore-forming RTX cytotoxin family, was revealed for pore formation, conceivably for a general pore-lining residue involved in ion conduction.     

Uptake of early infant diagnosis in Thailand’s national program for preventing mother-to-child HIV transmission and linkage to care, 2008–2011

Introduction

Early infant diagnosis (EID) has been a component of Thailand''s prevention of mother-to-child HIV transmission (PMTCT) programme since 2007. This study assessed the uptake, EID coverage, proportion of HIV-exposed infants receiving a definitive HIV diagnosis, mother-to-child transmission (MTCT) rates and linkage to HIV care and treatment.

Methods

Infant polymerase chain reaction (PCR) testing data from the National AIDS Program database were analyzed. EID coverage was calculated as the percentage of number of HIV-exposed infants receiving ≥1 HIV PCR test divided by the number of HIV-exposed infants estimated from HIV prevalence and live-birth registry data. Definitive HIV diagnosis was defined as having two concordant PCR results. MTCT rates were calculated based on infants tested with PCR and applied as a best-case scenario, and a sensitivity analysis was used to adjust these rates in average and worst scenarios. We defined linkage to HIV care as infants with at least one PCR-positive test who were registered with Thailand''s National AIDS Program. Chi-squared tests for linear trend were used to analyze changes in programme coverage.

Results

For 2008 to 2011, the average EID coverage rate increased from 54 to 76% (p<0.001), with 65% coverage (13,761/21,099) overall. The number of hospitals submitting EID samples increased from 458 to 645, and the percentage of community hospitals submitting samples increased from 75 to 78% (p=0.044). A definitive HIV diagnosis was made for 10,854 (79%) infants during this period. The adjusted MTCT rates had significantly decreasing trends in all scenarios. Overall, an estimated 53% (429/804) of HIV-infected infants were identified through the EID programme, and 80% (341/429) of infants testing positive were linked to care. The overall rate of antiretroviral treatment (ART) initiation within one year of age was 37% (157/429), with an increasing trend from 28 to 52% (p<0.001).

Conclusions

EID coverage increased and MTCT rates decreased during 2008 to 2011; however, about half of HIV-infected infants still did not receive EID. Most HIV-infected infants were linked to care but less than half initiated ART within one year of age. Active follow-up of HIV-exposed infants to increase early detection of HIV infection and early initiation of ART should be more widely implemented.     

Linoleic acid‐rich guava seed oil: Safety and bioactivity

Guava (Psidium guajava) is a widely consumed fruit and has been commercialized in markets. The seeds are by‐products of the processing procedures performed by the commercial guava juice industry. They are considered a nutritional resource that has been poorly utilized as they contain essential fatty acids such as linoleic acid (LA) and phenolics in abundance. In the study, guava seed oil (GSO) was used, which was obtained by hexane extraction of guava seeds to determine composition and test toxicity, cell migration, cancer cell viability, and plasmodium growth. GSO was found to be relatively nontoxic to normal hepatocytes and peripheral blood mononuclear cells, with mice for 14 days showing median lethal dose (LD₅₀) > 10 mg/kg and rats for up to 90 days. Surprisingly, the oil inhibited the proliferation of the human erythroleukemic cells in a dose‐dependent manner with the half maximal inhibitory concentration values of 155 and 137 μg/ml at 24 and 48 hr, respectively. Importantly, GSO at 500 μg/ml was found to increase the degree of migration of keratinocytes (HaCaT). These observations suggest that edible P. guajava seed oil, which is abundant with linoleic acid and antioxidants, can promote skin wound healing and inhibit the proliferation of leukemic cells.     

A chemically characterized ethanolic extract of Thai Perilla frutescens (L.) Britton fruits (nutlets) reduces oxidative stress and lipid peroxidation in human hepatoma (HuH7) cells

Perilla frutescens is cultivated in East Asian countries including Thailand, and the nutlets (single‐seeded fruits) are used as traditional and medicinal food. Perilla nutlets extracted by ethyl acetate (EA), 80% ethanol (Eth), and hot water (HW) sequentially were chemically characterized using high‐resolution accurate liquid chromatography‐mass spectrometry with the main compounds detected assigned as rosmarinic acid and derivatives of the flavones apigenin and luteolin, with the more diverse chemical composition observed with the Eth extract. All extracts showed dose‐dependent free‐radical scavenging activity, with the Eth extract the most potent (IC₅₀ = 3.43 mg/ml for ABTS^? scavenging and 0.27 mg/ml for DPPH^? scavenging). The Eth extract also inhibited AAPH‐induced hemolysis (IC₅₀ = 0.07 mg/ml) more potently than did the HW (IC₅₀ = 0.38 mg/ml) and EA extracts (IC₅₀ = 1.63 mg/ml). An MTT test revealed all the extracts were noncytotoxic at concentrations up to 200 μg/ml. Only the Eth and EA extracts showed protective effects against the generation of reactive oxygen species and lipid peroxidation in FeCl₃‐induced HuH7 cells in a dose‐dependent manner. Our findings suggest the Eth extract of Thai perilla nutlets, containing rosmarinic acid and flavones and their derivatives, may have potential to provide protection against oxidative stress in hepatic disorders.