PubMed Health⌕ Search

Biomedical subjects

F Fung

Publications and source records attributed to F Fung.

14 recordsLinked to original sources

The importance of colonic butyrate transport to the regulation of genes associated with colonic tissue homoeostasis.

The transition from normality to malignancy in colorectal cancer is characterized by alterations in the expression of genes associated with the maintenance of tissue homoeostasis. Butyrate, a product of microbial fermentation of dietary fibre in the colon, is known to regulate a number of genes associated with the processes of proliferation, differentiation and apoptosis of colonic epithelial cells, and, hence, homoeostasis of colonic tissue. We have shown previously that the transport of butyrate into colonocytes is of fundamental importance to butyrate's regulatory ability, and therefore sought to assess the expression profile of butyrate-responsive genes in colon cancer tissue, where the expression of the colonic luminal-membrane butyrate transporter, MCT1 (monocarboxylate transporter 1), is significantly down-regulated. In the present paper, we first employed microarray analysis to assess global changes in butyrate-responsive genes using HT29 human colon carcinoma cells treated with butyrate. There was consistency in the butyrate response of selected genes in two other human colonic cell lines (HCT116 and AA/C1) using quantitative real-time PCR. Furthermore, we report that expression levels of selected butyrate-responsive genes involved in the processes of proliferation, differentiation and apoptosis, are deregulated in colon cancer tissue, correlating with decreased expression of MCT1. These findings support our hypothesis that a reduction in MCT1 expression, and hence butyrate transport, can lead to a reduction in the intracellular butyrate levels required to regulate gene expression. Collectively, our results highlight the important contribution of butyrate transport to the maintenance of tissue homoeostasis and disease prevention.

Biological Transport↗

Are sleep problems under-recognised in general practice?

AIMS: To evaluate the frequency of sleep problems in Australian children aged 4.5-16.5 years, and to determine whether the frequency of sleep problems on questionnaire predicts the reporting of sleep problems at consultation. METHODS: Parents of 361 children (aged 4.5-16.5 years) attending their general practitioner for "sick" visits were asked to assess their child's sleep over the previous six months using the Sleep Disturbance Scale for Children, from which six sleep "disorder" factors and a total sleep problem score were obtained. RESULTS: The percentage of children with a total sleep problem score indicative of clinical significance (T score >70 or >95th centile) was 24.6% (89/361). Despite this high frequency, parents only addressed sleep problems in 4.1% (13/317) of cases and reported that GPs discussed sleep problems in 7.9% (25/317) of cases. Of the 79 children who reported total sleep problem T scores in the clinical range, only 13.9% (11/79) discussed sleep with their general practitioner within the previous 12 months. Regression analyses revealed an age related decrease in problems with sleep-wake transition and sleep related obstructive breathing; sleep hyperhydrosis, initiating and maintaining sleep, and excessive daytime sleepiness did not significantly decrease with age. No significant gender differences were observed. CONCLUSIONS: Results suggest that chronic sleep problems in Australian children are significantly under-reported by parents during general practice consultations despite a relatively high frequency across all age groups. Given the impact on children and families, there is a need for increased awareness of children's sleep problems in the community and for these to be more actively addressed at consultation.

Adolescent↗

Alternaria-associated asthma.

In addition to house dust mites, there is increasing evidence that mold allergens, especially Alternaria, are implicated in contributing to allergic reaction, rhinitis, and asthma indoors. Situations leading to the exacerbation of asthma in an employee were investigated and subsequent medical evaluations were performed. An industrial hygiene study was conducted and bioaerosol testing revealed several mold allergens were present. However, based on the medical evaluation and testing results (skin prick test and radioallergosorbent test [RAST]), it was concluded that Alternaria was inducing the respiratory reaction. Alternaria was present in the drip pan of the air conditioner unit and remedial actions were taken to remove the mold. Post-remedial bioaerosol sampling results revealed Alternaria was no longer present in the air and the employee returned to the office without recurrence of symptoms. Practically, several factors should be considered prior to concluding an association between exposure and illness. First, the employee's symptoms and signs should be consistent with a medical diagnosis. Second, there should be either in vitro or in vivo evidence of exposure. Third, environmental assessment should reveal evidence of plausible biological exposure. Fourth, there should be substantial improvement or even resolution of the illness after appropriate remediation of the health hazard. This case study illustrates the importance of teamwork by industrial hygienists and occupational health physicians in treatment and prevention of occupational and environmental diseases.

Adult↗

Styrene-induced peripheral neuropathy.

CASE REPORT: Styrene is a colorless, oily liquid most commonly found in paints, plastics, and resins. Like many solvents, styrene can cause intoxication and central nervous system depression when inhaled in high concentrations for extended periods. Rarely, styrene has been implicated as a cause of peripheral neuropathy. We describe a case of a previously healthy 57-year-old man who developed signs and symptoms consistent with a peripheral neuropathy after applying a fiberglass resin to the inside of a septic tank over a 2-day period. Nerve conduction tests verified examination findings. Styrene exposure should be minimized through the use of respirators and protective clothing to prevent this type of toxicity.

Blood Pressure↗

Stachybotrys, a mycotoxin-producing fungus of increasing toxicologic importance.

BACKGROUND: Stachybotrys as a fungus has been implicated as a source of mycotoxins. While the toxicity of several well-known mycotoxins (aflatoxins) is well documented, recent studies on Stachybotrys have raised the question that mycotoxins produced by this fungus may be responsible for the health effects of occupants in water-damaged buildings. METHODS: Published articles regarding Stachybotrys-related mycotoxins were reviewed with particular focus on human toxicity. RESULTS: A critical review of papers, reports, and studies on Stachybotrys mycotoxins revealed only descriptive reports of suspected animal and human poisoning secondary to consumption of mold-contaminated food products. No studies of good toxicologic and epidemiologic designs answer whether airborne mycotoxins produced by Stachybotrys could produce specific human toxicity. CONCLUSIONS: Current data on the toxicology of mycotoxins produced by Stachybotrys demonstrate that this group of mycotoxins is capable of producing immunosuppression and inflammatory insults to gastrointestinal and pulmonary systems. Case control study and case reports have suggested a possible association with environmental exposure to Stachybotrys mycotoxins, although a firm causal relationship has not been firmly established. Additional studies are needed to document that humans with sufficient exposure to these mycotoxins develop compatible clinical and pathologic pictures as demonstrated in animal models.

Animals↗

The development of a health technology assessment program. The case of Alberta.

Canada comprises 10 provinces and 2 territories. The Constitution assigns responsibility for the provision of health services in the provinces to provincial governments. Over the past 5 years, provincial governments have identified technology assessment as a priority. This paper describes an initiative taken by the government of the province of Alberta to develop a health technology assessment program for that province.

Alberta↗

In-vitro interaction of a novel immunosuppressant, FK 506, and antacids.

The effect of selected antacids on the amount of FK 506 in solution in simulated gastric juice has been studied. FK 506 (2.5 mg) was incubated in 100 mL simulated gastric fluid (SGF) with the equivalent of 500 mg of various antacids. The addition of Mylanta and Tums resulted in 14 and 30% loss of FK 506, respectively, in 24 h; 98% loss was observed in 12 h in the presence of Mag-Ox; 100% loss was observed in the presence of magnesium oxide powder in 2 h. The loss of FK 506 from these solutions appears to be due to a pH mediated degradation of FK 506. The addition of aluminium hydroxide gel USP (Roxane) to the FK 506 solution resulted in a 35% loss within 2 min but no further loss was noted for 24 h, indicative of adsorption of FK 506. These results suggest that until additional in-vivo studies are carried out, it is prudent not to dose FK 506 and antacids at the same time to avoid potential interactions.

Antacids↗

Occupational disease surveillance of an aircraft rework facility.

Analysis of the 1987-1988 morbidity data of an aircraft rework facility's 6,672 employees identified 118 patients with occupational diseases. In our study, 61 cases (52%) involved eye and skin conditions. This was comparable to the State of California occupational diseases report. However, systemic conditions appeared to be higher (24% vs. 7%) in the study group, and this finding may need further investigation to clarify its significance. Patients employed as craftworkers accounted for nearly half of all reported occupational diseases. Federal workers in this facility appeared to have a higher percentage (70%) of "no time lost" when compared with that of the State of California report (54%). The utility of morbidity data in the prevention of occupational diseases is discussed.

Adolescent↗

Postsplenectomy sepsis and other complications following staging laparotomy for Hodgkin's disease in childhood.

This is a survey of 234 pediatric patients in whom staging laparotomy/splenectomy was carried out (1975 to 1981) in the course of the Intergroup Hodgkin's Disease in Childhood Study (IHDCS). Relapse has occurred in 44 of these patients, and 12 have died, 7 secondary to extension of lymphoma, 2 with herpes or pneumocystis infections, 2 with leukemia, and 1 from an unrelated accident. During the period of surveillance (mean 5.5 yr), five episodes of bacterial sepsis (positive blood cultures) have occurred, including two due to Streptococcus pneumoniae; and three, to Hemophilus influenzae. The former occurred in the small group of patients in this series who had not received the prescribed pneumococcal vaccination. No fatalities were associated with these septic episodes. Intestinal obstruction secondary to adhesions (benign) occurred in eight patients and was managed without intestinal resection or mortality. One patient required operative release of an obstructed ureter following laparotomy, and one, oophorectomy for an infarcted (transposed) ovary.

Adolescent↗

Antidepressant drugs and dopamine uptake in different brain regions.

The effect of trycyclic antidepressants on 3H-dopamine uptake into synaptosomes obtained from rat striatum and mesolimbic cortical areas was examined. Chlorimipramine was found to be the most potent uptake inhibitor (IC50 of 3.2-3.8 X 10(-6) M) in both brain regions. Desmethylimipramine, protryptyline and iprindole were approximately one-half as potent (IC50 of 5.9-8.5 X 10(-6) M) in both brain areas. Kinetic constants obtained from Line-weaver-Burk plots in both areas revealed no alteration in Km for transport and a decrease in V max thus indicating a non-competitive inhibition. The effect of chlorimipramine on the release of 3H-dopamine from striatal synaptosomes required a concentration 10(-5) M for 50% release in 5 min. It is suggested that dopamine uptake inhibition may play some role in the action of tricyclic drugs, e.g., activation of schizophrenic psychopathology but that this action can not be solely responsible for their antidepressant properties.

Animals↗