Synthesis of hydroxyapatite via mechanochemical treatment.

Hydroxyapatite powder was synthesized with calcium pyrophosphate (Ca2P2O7) and calcium carbonate (CaCO3) through solid-state reaction. The two powders were mixed in acetone and water, respectively, and the single phase of hydroxyapatite was observed to occur only in the powder milled in water, without the additional supply of water vapor during heat-treatment at 1100 degrees C for 1 h. The results were explained in terms of the mechanochemical reaction that could supply enough amount of hydroxyl group to the starting powders to form a single phase of hydroxyapatite. Practical implication of the results is that the powder of high crystalline hydroxyapatite can be obtained by the simple milling in water and subsequent heat-treatment.     

Race and the treatment of cytomegalovirus retinitis in a cohort of patients with acquired immunodeficiency syndrome.

This historical cohort study assessed the impact of race on critical factors in the diagnosis and drug treatment of cytomegalovirus (CMV) retinitis in acquired immunodeficiency syndrome (AIDS) patients over a 7-year period. The study subjects included 194 adult patients with a history of AIDS who were treated for CMV retinitis between September 1987 and September 1994. Abstracted inpatient hospital medical records and a statewide automated AIDS database were the primary sources of data. Patients were assessed for severity of CMV retinitis at diagnosis, time from initial CMV retinitis diagnosis to first treatment, survival from diagnosis of AIDS, and initiation of drug treatment for CMV retinitis. Results indicated a significant difference in the severity of CMV retinitis at diagnosis by race. Patients diagnosed with early disease were more likely to be white, whereas patients diagnosed with severe disease were more likely to be black. There was no difference in the type of CMV retinitis treatment or patient survival time after diagnosis, nor time to treatment once diagnosed by race. These results suggest that differences in survival may not be the result of discrimination against black patients and may be due more likely to practices associated with accessing medical treatment.     

Hemodynamic and electrophysiological effects of mercury in intact anesthetized rabbits and in isolated perfused hearts

Using intact anesthetized rabbits and isolated perfused hearts, the hemodynamic and electrophysiological effects of mercury (Hg) were examined in order to assess the role of cardiovascular dysfunction in Hg intoxication. The most consistent and prominent cardiovascular effect was a significant reduction in blood pressure. This cardiodepressive action was probably brought about by the primary action of Hg on the heart rather than by altered sympathetic activity, as evidenced by normal renal nerve activity at times when the hemodynamic actions of Hg were clearly manifest. Although the principal target organ for the toxic actions of inorganic Hg is the kidney, chronic exposure to both inorganic and organic Hg frequently results in signs and symptoms of CNS dysfunction. The profound hemodynamic effects of Hg that we have observed emphasize the potential importance of Hg cardiotoxicity and indicate the need to differentiate between the primary and the secondary effects of Hg intoxication on CNS tissues for evaluation of the toxic effects of Hg compounds.     

Korean primary caregivers' perceptions about secondary caregivers of demented elderly: Are secondary caregivers source of support or stress?

The purpose of this study was to explore the relationship between primary caregivers and secondary caregivers of demented elderly. To achieve this purpose, two research questions were raised. What are perceptions of caregivers with regard to secondary caregivers' help? And what are subjective factors that affect primary caregivers' perceptions about secondary caregivers' help?
Most existing studies have shown that secondary caregivers' help plays an essential role in alleviating caregivers' burden. However, recently some research showed secondary caregivers' help as source of stress. ^1–6 However, existing studies showed little about how primary caregivers perceived secondary caregivers' help.
In-depth interviews of a qualitative research method were used for this study. Using purposive sampling in consideration of caregivers' relationship with the demented elderly, 10 primary caregivers were selected: two wives, two husbands, two daughters, and four daughters-in-law of patients. Qualitative data were collected from relatively unstructured in-depth interviews with 10 primary caregivers. An average of 2 hours was taken for each interview. Ten interviews were tape-recorded, and later fully transcribed. This qualitative data were analyzed according to constant comparative method described by Glaser and Strauss.     

Induction of apoptosis by carboplatin and hyperthermia alone or combined in WERI human retinoblastoma cells.

This paper investigated the induction of apoptosis and perturbation of cell cycle progression caused by carboplatin (CPt) and hyperthermia alone or combined in WERI human retinoblastoma cells in vitro. An incubation of the cells with 25 or 50 microm of CPt at 37 degrees C caused apoptosis, which progressively increased during the 24-72 h treatment. Hyperthermia at 42.5 degrees C for 1 h induced apoptosis, which became significant from 24 h after the heating. Heating the cells in the presence of CPt and subsequent incubation with CPt was far more effective than treating the cells with hyperthermia or CPt treatment alone in inducing apoptosis in the WERI cells, indicating that the combination of these two modalities is potentially useful for the treatment of retinoblastoma. It appeared that the apoptosis in WERI cells caused by hyperthermia and CPt occurs during G1 phase. An interesting observation was that caspase 9 activation preceded the release of cytochrome C from mitochondria during apoptosis in WERI cells, contrary to the general notion that caspase 9 is activated by cytochrome C.     

Incidence and prevalence of ulcerative colitis in the Songpa-Kangdong District, Seoul, Korea, 1986-1997

BACKGROUND AND AIMS: Ulcerative colitis (UC) is regarded as a rare disease in developing countries, but accurate data are generally lacking. We performed the present study to evaluate the incidence and prevalence of UC in Korea. METHODS: A retrospective study was performed from 1986 to 1997 in the Songpa-Kangdong district of Seoul, Korea. To recruit UC patients as completely as possible, multiple information sources including all medical facilities in the study area and three referral centres located nearby, but outside the study area were used. The incidence and prevalence rates were adjusted using the 1997 Korean population statistics. RESULTS: During the study period, a total of 94 incident cases were identified, for an adjusted mean annual incidence rate of 0.68 per 100,000 inhabitants. On 31 December 1997, 91 patients with UC lived in the study area, giving an adjusted prevalence rate of 7.57 per 100,000 inhabitants. By using the Poisson regression analysis, the annual incidence rate increased significantly from 0.20 per 100,000 inhabitants in 1986-1988 to 1.23 per 100,000 inhabitants in 1995-1997 (P < 0.005). Patient age at diagnosis, the interval from onset of symptoms to diagnosis, and the disease extent at diagnosis were fairly constant throughout the study period. CONCLUSIONS: The incidence and prevalence of UC in our study area are still low compared with those of Western countries, but the incidence rate is steadily increasing.     

Gene Polymorphisms of Endothelial Nitric Oxide Synthase and Angiotensin-converting Enzyme in Patients with Lung Cancer

The objectives of this study were to examine the possible involvement of endothelial nitric oxide synthase (ecNOS) and angiotensin-converting enzyme (ACE) genes in the genetic basis of lung cancer. Two hundred eighteen patients with lung cancer and 121 healthy subjects were included in this study. The ecNOS and ACE genotypes were determined in all subjects by polymerase chain reaction. The distribution of genotypes of ecNOS gene was significantly different in the lung cancer group than in the control population. ACE genotype distribution was not significantly different in the lung cancer group compared with the control group. These results suggest that polymorphisms of the ecNOS gene, but not the ACE gene, may be associated with the development of lung cancer. Accepted for publication: 31 October 2000     

Patient adherence improves glycemic control

PURPOSE: The purpose of this study was to assess the influence of appointment keeping and medication adherence on HbA1c. METHODS: A retrospective evaluation was performed in 1560 patients with type 2 diabetes who presented for a new visit to the Grady Diabetes Clinic between 1991 and 2001 and returned for a follow-up visit and HbA1c after 1 year of care. Appointment keeping was assessed by the number of scheduled intervening visits that were kept, and medication adherence was assessed by the percentage of visits in which self-reported diabetes medication use was as recommended at the preceding visit. RESULTS: The patients had an average age of 55 years, body mass index (BMI) of 32 kg/m2, diabetes duration of 4.6 years, and baseline HbA1c of 9.1%. Ninety percent were African American, and 63% were female. Those who kept more intervening appointments had lower HbA1c levels after 12 months of care (7.6% with 6-7 intervening visits vs 9.7% with 0 intervening visits). Better medication adherence was also associated with lower HbA1c levels after 12 months of care (7.8% with 76%-100% adherence). After adjusting for age, gender, race, BMI, diabetes duration, and diabetes therapy in multivariate linear regression analysis, the benefits of appointment keeping and medication adherence remained significant and contributed independently; the HbA1c was 0.12% lower for every additional intervening appointment that was kept (P = .0001) and 0.34% lower for each quartile of better medication adherence (P = .0009). CONCLUSION: Keeping more appointments and taking diabetes medications as directed were associated with substantial improvements in HbA1c. Efforts to enhance glycemic outcomes should include emphasis on these simple but critically important aspects of patient adherence.