Hyperbaric oxygen therapy attenuates D-galactose-induced-age-related cardiac dysfunction through mitigating cardiac mitochondrial dysfunction in pre-diabetic rats

Background

D-galactose (D-gal) induced ageing has been shown to exacerbate left ventricular (LV) dysfunction via worsening of apoptosis and mitochondrial dysfunction in the heart of obese rats. Hyperbaric oxygen therapy (HBOT) has been demonstrated to exert anti-inflammatory and anti-apoptotic effects in multiple neurological disorders. However, the cardioprotective effect of HBOT on inflammation, apoptosis, LV and mitochondrial functions in D-gal induced ageing rats in the presence of obese-insulin resistant condition has never been investigated.

Purpose

We sought to determine the effect of HBOT on inflammation, apoptosis, mitochondrial functions and LV function in pre-diabetic rats with D-gal induced ageing. We hypothesized that HBOT attenuates D-gal induced cardiac mitochondrial dysfunctions and reduces inflammation and apoptosis, leading to improved LV function in pre-diabetic rats.

Methods

Forty-eight male Wistar rats were fed with either normal diet or high-fat diet for 12 weeks. Then, rats were treated with either vehicle groups (0.9% NSS, subcutaneous injection (SC)) or D-gal groups (150 mg/kg/day, SC) for 8 weeks. At week 21, rats in each group were equally divided into 6 sub-groups: normal diet fed rats treated with vehicle (NDV) sham, normal diet fed rats treated with D-gal (NDDg) sham, high fat diet fed rats treated with D-gal (HFDg) sham, high fat diet fed rats treated with vehicle (HFV) + HBOT, NDDg + HBOT and HFDg + HBOT. Sham treated rats were given normal concentration of O2 (flow rate of 80 L/min, 1 ATA for 60 minutes), whereas HBOT treated rats were subjected to 100% O2 (flow rate of 250 L/min, 2 ATA for 60 minutes), given once daily for 2 weeks.

Results

Under obese-insulin resistant condition, D-gal-induced ageing aggravated LV dysfunction (Fig 1A) and impaired cardiac mitochondrial function, increased cardiac inflammatory and apoptotic markers (Fig 1B). HBOT markedly reduced cardiac TNF-α level and TUNEL positive apoptotic cells, and improved cardiac mitochondrial function as indicated by decreased mitochondrial ROS production, mitochondrial depolarization and mitochondrial swelling, resulting in the restoration of the normal LV function in HFV and NDDg rats, compared to sham NDDg rats. In addition, in HFDg treated rats, HBOT attenuated cardiac TNF-α level, TUNEL positive apoptotic cells and cardiac mitochondrial dysfunction, compared to sham HFDg rats, leading to improved cardiac function as indicated by increased %LV ejection fraction (LVEF) (Figure 1).

Conclusion

HBOT efficiently alleviates D-gal-induced-age-related LV dysfunction through mitigating inflammation, apoptosis and mitochondrial dysfunction in pre-diabetic rats.

Figure 1

Funding Acknowledgement

Type of funding source: Public grant(s) – National budget only. Main funding source(s): 1. The National Science and Technology Development Agency Thailand, 2. Thailand Research Fund Grants

Outbreak of Tsukamurella species bloodstream infection among patients at an oncology clinic, West Virginia, 2011-2012

OBJECTIVE

To determine the source and identify control measures of an outbreak of Tsukamurella species bloodstream infections at an outpatient oncology facility.

DESIGN

Epidemiologic investigation of the outbreak with a case-control study.

METHODS

A case was an infection in which Tsukamurella species was isolated from a blood or catheter tip culture during the period January 2011 through June 2012 from a patient of the oncology clinic. Laboratory records of area hospitals and patient charts were reviewed. A case-control study was conducted among clinic patients to identify risk factors for Tsukamurella species bloodstream infection. Clinic staff were interviewed, and infection control practices were assessed.

RESULTS

Fifteen cases of Tsukamurella (Tsukamurella pulmonis or Tsukamurella tyrosinosolvens) bloodstream infection were identified, all in patients with underlying malignancy and indwelling central lines. The median age of case patients was 68 years; 47% were male. The only significant risk factor for infection was receipt of saline flush from the clinic during the period September-October 2011 (P = .03), when the clinic had been preparing saline flush from a common-source bag of saline. Other infection control deficiencies that were identified at the clinic included suboptimal procedures for central line access and preparation of chemotherapy.

CONCLUSION

Although multiple infection control lapses were identified, the outbreak was likely caused by improper preparation of saline flush syringes by the clinic. The outbreak demonstrates that bloodstream infections among oncology patients can result from improper infection control practices and highlights the critical need for increased attention to and oversight of infection control in outpatient oncology settings.

Two-dose varicella vaccine effectiveness and rash severity in outbreaks of varicella among public school students

BACKGROUND

Universal 2-dose varicella vaccination was recommended in 2006 to further reduce varicella disease burden. This study examined 2-dose varicella vaccine effectiveness (VE) and rash severity in the setting of school-associated varicella outbreaks.

METHODS

A case control study was conducted from January 2010 to May 2011 in all West Virginia public schools. Clinically diagnosed cases from varicella outbreaks were matched with classmate controls. Vaccination information was collected from school, health department and healthcare provider immunization information systems.

RESULTS

Among the 133 cases and 365 controls enrolled, VE against all varicella was 83.2% [95% confidence interval (CI): 69.2%-90.8%] for 1-dose of varicella vaccine and 93.9% (95% CI: 86.9%-97.1%) for 2-dose; the incremental VE (2-dose vs. 1-dose) was 63.6% (95% CI: 32.6%-80.3%). In preventing moderate/severe varicella, 1-dose varicella vaccine was 88.2% (95% CI: 72.7%- 94.9%) effective, and 2-dose vaccination was 97.5% (95% CI: 91.6%-99.2%) effective, with the incremental VE of 78.6% (95% CI: 40.9%-92.3%). One-dose VE declined along with time since vaccination (VE = 93.0%, 88.0% and 81.8% in <5, 5-9 and ≥ 10 years after vaccination, P = 0.001 for trend). Both 1- and 2-dose breakthrough cases had milder rash than unvaccinated cases (<50 lesion: 24.6%, 49.1% and 70.0% in unvaccinated, 1-dose and 2-dose cases, P < 0.001), and no severe disease was found in 2-dose cases.

CONCLUSIONS

Two-dose varicella vaccination is highly effective and confers higher protection than a 1-dose regimen. High 2-dose varicella vaccination coverage should maximize the benefits of the varicella vaccination program and further reduce varicella disease burden in the United States.

Dual resistance to adamantanes and oseltamivir among seasonal influenza A(H1N1) viruses: 2008-2010

Two distinct genetic clades of seasonal influenza A(H1N1) viruses have cocirculated in the recent seasons: clade 2B oseltamivir-resistant and adamantane-susceptible viruses, and clade 2C viruses that are resistant to adamantanes and susceptible to oseltamivir. We tested seasonal influenza A(H1N1) viruses collected in 2008-2010 from the United States and globally for resistance to antivirals approved by the Food and Drug Administration. We report 28 viruses with both adamantane and oseltamivir (dual) resistance from 5 countries belonging to 4 distinct genotypes. Because of limited options for antiviral treatment, emergence of dual-resistant influenza viruses poses a public health concern, and their circulation needs to be closely monitored.

Health effects associated with indoor swimming pools: A suspected toxic chloramine exposure

OBJECTIVES

A cohort and environmental study tested the hypothesis that suspected exposure to chloramines (by-products of chlorine for disinfection and ammonia from human sources) from a hotel's indoor swimming pool was associated with an outbreak among children who had attended a party at the pool.

STUDY DESIGN

Retrospective cohort study.

METHODS

A case was defined as any hotel guest/visitor on 5-6 October 2002 who experienced three or more symptoms typical of chloramine exposure on either day after visiting the hotel. A cohort study and an environmental assessment were performed to determine the association between pool exposure and illness.

RESULTS

Of 128 individuals interviewed, 32 met the case definition. Common symptoms among case patients were cough (84%), eye irritation (78%) and rash (34%). Illness was associated with entering the pool area [odds ratio (OR) 19.9; 95% confidence interval (CI) 2.3-172], but more strongly with swimming (OR 72.0; 95% CI 9.1-568). Pool chloramine levels on 6 October 2002 were > or = 0.7ppm (optimal level=0ppm; state maximum=0.5ppm). The pool operator lacked formal training in pool maintenance.

CONCLUSIONS

High chloramine levels may have caused illness in individuals who were either in or near the pool. This outbreak underscores the need for regular pool maintenance, improved air quality, education and certification for all operators of public and semipublic pools, and education about healthy swimming practices.

Prediction of 'highly skin smear positive' cases among MB leprosy patients using clinical parameters

Although 'highly skin smear positive' MB leprosy cases are known to be at high risk of relapse after release from treatment, and have been recommended to receive 'prolonged duration' MDT, government field-based control programmes without skin smear facilities have no simple alternative method to detect such cases. This study reports a significant prevalence of 'highly smear positive' cases amongst 2374 new multibacillary cases recently surveyed by skin smears in Nepal, and retrospectively analyses 555 newly detected, previously untreated BL and LL cases to identify clinical and laboratory parameters that may be associated with a 'highly positive skin smear'. While some parameters showed high sensitivity in predicting 'highly positive smear' status, none showed both high sensitivity and high specificity simultaneously.

A comparative study of intervention methods (full, partial and non-integration) on late case detection and treatment irregularity in Yangon, Myanmar

The high percentage (20%) of new cases with grade 2 disabilities, and a low treatment regularity of 47% indicated problems in case detection and case holding in Urban Yangon. The fact that Urban Health Centers (UHCs) were not involved in leprosy control programme might have had an adverse influence. To compare the effectiveness of two methods of integration (full and partial) of urban leprosy services in terms of early case detection and regularity of treatment this study was conducted, in an urban area. Two townships with similar leprosy prevalence, staff infrastructure, socio-economic status, transport, communication and working capacity of the Township Medical Officers (TMOs) were chosen for this intervention study: UHC-A(Thingangyun) for full integration and UHC-B(Tamwe) for partial integration and the remaining 14 townships as non-integrated areas served by the Central Special Skin Clinic (CSSC). This study has shown that it was possible to fully integrate Leprosy Control Programme (LCP) into the Urban Health Centres [Basic Health Services (BHS)] in Urban Yangon. Case detection could be improved by active case finding such as contact examination and school examination conducted by the personnel of UHCs. Treatment regularity was found to be directly proportional to prompt defaulter retrieval action and the motivational level of the TMO and peripheral BHS workers. There were more complaints from patients (8.1%) treated at UHC-A when compared to CSSC (6.7%). Among defaulters there were more adults than children, more males than females and more PB than MB patients.

Acceptance of short course artesunate plus mefloquine drug combination by malaria patients in rural Myanmar

A cross sectional study was carried out in a rural area of Myanmar to identify malaria patients' acceptance of artesunate plus mefloquine drug combination and to determine the cost borne by patients. The majority (88.5%) preferred this new regimen rather than the other ones they had used before; conviction of drug efficacy was the reason given for the preference by most of them. Traveling on foot to rural health centers or a health assistant's residence for getting the drugs was found to be the main route. Average cost incurred by a patient to get the drug was found to be 274.22 Kyats. Among the cost items, drug cost was the highest item that they had used.

Leprosy elimination through integrated basic health services in Myanmar: the role of midwives

Myanmar is one of the top 16 countries identified by WHO as being hyperendemic for leprosy. Multi-drug therapy (MDT) was introduced in 1988 as a vertical programme and gradually integrated into the basic health services (BHS), achieving 100% coverage over the registered cases by 1995. To achieve maximum coverage of and benefit for patients, both leprosy vertical staff and BHS staff were trained to implement MDT whilst performing routine BHS activities. This included a total of 8615 trained midwives who were mobilized for the nationwide leprosy elimination programme (LEP). They worked at village level in various parts of the country and were willing and able to carry out basic tasks in leprosy management, such as the implementation of MDT using blister-calender packs carrying a month's supply of drugs. This study was performed to assess the workload of midwives and their attitude towards LEP. The authors conclude that midwives in Myanmar show a high level of commitment and reliability, which are essential contributing factors to achieve the current goal of leprosy elimination by the year 2000. Along with the present trend of decreasing prevalence rate, leprosy could no longer be considered as a public health problem at national level by the year 2000 in Myanmar. However, because of its long incubation period, new leprosy patients may arise even after the elimination target is achieved, whilst many other patients may become disabled. A community-based sustainable approach for the post-elimination phase, after the year 2000, will be essential and the contribution of the midwives may be of considerable importance.

Serum cortisol levels in patients with uncomplicated and cerebral malaria

Ten patients with uncomplicated malaria, ten with cerebral malaria and 37 controls (blood donors from blood bank) were included in the study. The serum cortisol levels of the patients were determined daily for 7 days while they were at the hospital. A radio-immunoassay method was used for quantitative measurement of cortisol in human serum. The mean serum cortisol level of patients with uncomplicated malaria was 528.2 +/- 123.9 nmol/l, with cerebral malaria was 516.0 +/- 80.5 nmol/l, and in controls was 393.8 +/- 141.0 nmol/l. There was a significant rise of serum cortisol levels in patients with malaria when compared to controls at the day of admission to hospital. There was no significant difference between uncomplicated malaria patients and those with cerebral malaria. There was also no significant difference between the different days of treatment up till day 7. We found no cortisol insufficiency in cases with falciparum malaria during acute and convalescent stages of illness.

Influence of blister packaging on the efficacy of artesunate + mefloquine over artesunate alone in community-based treatment of non-severe falciparum malaria in Myanmar

Three studies were carried out to determine the need, acceptability, and efficacy of adding mefloquine to artemisinin derivatives (AD) for the first-line treatment of uncomplicated falciparum malaria. The first was a retrospective study of 255 basic health workers which showed that their recommendation of AD to patients depended on their level of training. None of the paramedics/midwives and only 9% of 129 doctors had prescribed AD, and no one had recommended AD in combination with mefloquine; 72% of patients used courses that were too short for parasitological cure. To promote the addition of mefloquine to AD regimens we conducted intervention workshops with health care providers and subsidized the cost of mefloquine to patients. In the second study, we interviewed 200 patients before and after the intervention to evaluate drug compliance with full doses of AD and use of subsidized mefloquine. After the intervention, we found that only 3.6% had used mefloquine and 62% had taken non-curative doses of AD. In the third study, we provided blister packs of medication in daily doses and compared the intake of AD + placebo (158 patients) with that of AD + mefloquine (222 patients) for 5 days. The compliance with both regimens was 99%. Blood smears for parasites on day 28 showed one positive in the AD + mefloquine group and 7 positive in the AD group. We conclude that provision of blister packs of daily doses is a very effective way to improve compliance with short courses and drug combinations, but the efficacy of the combination in Myanmar in this particular study was only marginally higher than that of AD alone.

Prevalence of colour blindness among patients with leprosy

Using Ishihara test plates the prevalence of colour blindness was studied on six hundred and ninety-seven leprosy patients and two hundred and ninety-two normal healthy controls. 7.88% of male patients with tuberculoid leprosy, 12.18% of male patients with lepromatous leprosy, and 0.67% of male controls were detected to be colour blind (red-green deficiency or total colour weakness). The differences between the different groups are significant. Among female patients and controls, only one lepromatous leprosy patient was detected to have red-green deficiency. This suggests the possibility of a genetic predisposition to Mycobacterium leprae infection in patients with leprosy.

The effect of artemether plus mefloquine on Myanmar patients with complicated falciparum malaria

The effect of artemether plus mefloquine versus quinine on 35 patients with complicated falciparum malaria including 5 patients with cerebral malaria were studied. All patients treated with the artemether-mefloquine combination survived and all were free from toxic effects of the drugs. Three patients on quinine therapy died. The mortality rate was 8.5%. The mean parasite clearance time of patients treated with artemether plus mefloquine was significantly shorter than those treated with quinine but there was no significant difference in the mean fever clearance of the two groups of patients. There was no recrudescence with artemether and mefloquine; the recrudescence rate was 5.5% with quinine. The study showed that the artemether-mefloquine combination is superior to quinine for the treatment of patients with complicated falciparum malaria, including cerebral malaria.

Estimation of leprosy prevalence in Bago and Kawa townships using two-stage probability proportionate to size sampling technique

Two surveys to estimate leprosy prevalence using two-stage probability proportionate to size sampling technique were conducted in Bago and Kawa townships. A total of 3519 and 3739 individuals were examined in each township. The two surveys were finished within 25 (Bago) and 30 (Kawa) working days at a cost of Kyats 10,000 (US $1500) for each survey. The estimated leprosy prevalence obtained in Bago was 9.95 per 1000 population (95% confidence interval (CI): 7.11-12.78) and in Kawa it was 12.04 per 1000 population (95% CI: 8.85-15.22). A total of 30 (Bago) and 34 (Kawa) new leprosy cases were detected in the two surveys. Grade I disability was seen to be 20% in Bago and 18.78% in Kawa, whereas grade II disability was 17.14% in Bago and 15.56% in Kawa.

The effect of tetanus toxoid in leprosy patients

Since cases of lepra reaction following smallpox vaccination and BCG vaccination had been reported the effect of tetanus immunisation on leprosy patients (whether it may provoke a lepra reaction or not) was studied. Three doses of purified tetanus toxoid (one ml initially, one ml after six weeks and one ml after six months) were given to 357 leprosy patients and 60 patients living in the same environ were followed as controls. The antibody response following immunisation was followed in six lepromatous leprosy patients using toxin antitoxin neutralisation test at the Lf/1000 level in mice and in three of them the antibody titre of leprosy patients rose to satisfactory level. The number of lepra reactions in these patients was monitored for nine months (two months before vaccination, during the six months period of vaccination and one month after the last dose of vaccine). There was no significant rise in the number of patients with reaction following the vaccination.

The effect of mefloquine-sulfadoxine-pyrimethamine vs quinine on patients with complicated falciparum malaria

Sixty-six patients with complicated falciparum malaria (defined as anaemia, hyperpyrexia, jaundice, or more than 2% of RBC parasitised) were studied. Patients with cerebral signs and symptoms were not included in the study. Patients were randomised in pairs to receive either mefloquine 750 mg, sulfadoxine 1500 mg and pyrimethamine 75 mg (MSP) single oral dose or quinine (10 mg/kg tds X 7 days oral therapy). All the patients were admitted in hospital for 7 days and were followed on days 14, 21 and 28. All patients survived. The parasite clearance times in MSP treated patients were significantly shorter then those treated with quinine. There was no difference in fever clearance time in the two groups of patients. One patient was resistant to MSP at RII level and 5 patients were resistant at RI level. Among patients treated with quinine 3 patients were resistant at RI level.

Australia antigen and antibody in British patients with leprosy

Seventy-five sera collected from leprosy patients in England were tested for Australia antigen and antibody. Australia antigen was detected in only two patients with lepromatous leprosy and in one patient with borderline pure leprosy. Antibody to Australia antigen was found in one patient with lepromatous leprosy. These findings differ from previous reports and it is suggested that the frequency of Australia antigen in lepromatous leprosy is a function of the incidence of this antigen in the general population rather than increased genetic susceptibility to chronic infection.

Nephrotic syndrome in monkey infected with human quartan malaria

A splenectomized aotus monkey infected with human quartan malaria (Plasmodium malariae) developed oedema and proteinuria. Histological examination revealed a generalized diffuse glomerulonephritis and immunofluorescent staining showed granular deposits of IgM in the glomeruli. The pathological picture resembled that shown by human patients with the quartan malaria nephrotic syndrome.