Towards health monitoring using remote heart rate measurement using digital camera: A feasibility study.

The paper presents a feasibility study for heart rate measurement using a digital camera to perform health monitoring. The feasibility study investigates the reliability of the state of the art heart rate measuring methods in realistic situations. Therefore, an experiment was designed and carried out on 45 subjects to investigate the effects caused by illumination, motion, skin tone, and distance variance. The experiment was conducted for two main scenarios; human-computer interaction scenario and health monitoring scenario. The human-computer scenario investigated the effects caused by illumination variance, motion variance, and skin tone variance. The health monitoring scenario investigates the feasibility of health monitoring at public spaces (i.e. airports, subways, malls). Five state of the art heart rate measuring methods were re-implemented and tested with the feasibility study database. The results were compared with ground truth to estimate the heart rate measurement error. The heart rate measurement error was analyzed using mean error, standard deviation; root means square error and Pearson correlation coefficient. The findings of this experiment inferred promising results for health monitoring of subjects standing at a distance of 500 cm.

Novel health monitoring method using an RGB camera.

In this paper we present a novel health monitoring method by estimating the heart rate and respiratory rate using an RGB camera. The heart rate and the respiratory rate are estimated from the photoplethysmography (PPG) and the respiratory motion. The method mainly operates by using the green spectrum of the RGB camera to generate a multivariate PPG signal to perform multivariate de-noising on the video signal to extract the resultant PPG signal. A periodicity based voting scheme (PVS) was used to measure the heart rate and respiratory rate from the estimated PPG signal. We evaluated our proposed method with a state of the art heart rate measuring method for two scenarios using the MAHNOB-HCI database and a self collected naturalistic environment database. The methods were furthermore evaluated for various scenarios at naturalistic environments such as a motion variance session and a skin tone variance session. Our proposed method operated robustly during the experiments and outperformed the state of the art heart rate measuring methods by compensating the effects of the naturalistic environment.

Effect of motion artifact on digital camera based heart rate measurement.

Remote health monitoring is an emerging field in biomedical technology. Digital camera based heart rate measurement method is a recent development which would make remote health monitoring reliable and sustainable in future. This paper presents an investigation on the effect of motion artifact on digital camera-based heart rate measurement. The paper will discuss details on the principles and effects of motion artifacts on photoplethysmography signals. An experiment is conducted using publicly available MAHNOB-HCI database. We have investigated the effects of static scenarios, scenarios involving rigid motion and scenarios involving non-rigid motion. The experiment was tested on state of the art digital camera based heart rate measuring methods. The results showed the effectiveness of the methods and provide a direction to overcome/minimize the effect of motion artifacts for future research.

Diaphragm remodeling and compensatory respiratory mechanics in a canine model of Duchenne muscular dystrophy.

Ventilatory insufficiency remains the leading cause of death and late stage morbidity in Duchenne muscular dystrophy (DMD). To address critical gaps in our knowledge of the pathobiology of respiratory functional decline, we used an integrative approach to study respiratory mechanics in a translational model of DMD. In studies of individual dogs with the Golden Retriever muscular dystrophy (GRMD) mutation, we found evidence of rapidly progressive loss of ventilatory capacity in association with dramatic morphometric remodeling of the diaphragm. Within the first year of life, the mechanics of breathing at rest, and especially during pharmacological stimulation of respiratory control pathways in the carotid bodies, shift such that the primary role of the diaphragm becomes the passive elastic storage of energy transferred from abdominal wall muscles, thereby permitting the expiratory musculature to share in the generation of inspiratory pressure and flow. In the diaphragm, this physiological shift is associated with the loss of sarcomeres in series (∼ 60%) and an increase in muscle stiffness (∼ 900%) compared with those of the nondystrophic diaphragm, as studied during perfusion ex vivo. In addition to providing much needed endpoint measures for assessing the efficacy of therapeutics, we expect these findings to be a starting point for a more precise understanding of respiratory failure in DMD.

Novel techniques for enhancement and segmentation of acne vulgaris lesions.

BACKGROUND: More than 99% acne patients suffer from acne vulgaris. While diagnosing the severity of acne vulgaris lesions, dermatologists have observed inter-rater and intra-rater variability in diagnosis results. This is because during assessment, identifying lesion types and their counting is a tedious job for dermatologists. To make the assessment job objective and easier for dermatologists, an automated system based on image processing methods is proposed in this study. OBJECTIVES: There are two main objectives: (i) to develop an algorithm for the enhancement of various acne vulgaris lesions; and (ii) to develop a method for the segmentation of enhanced acne vulgaris lesions. METHODS: For the first objective, an algorithm is developed based on the theory of high dynamic range (HDR) images. The proposed algorithm uses local rank transform to generate the HDR images from a single acne image followed by the log transformation. Then, segmentation is performed by clustering the pixels based on Mahalanobis distance of each pixel from spectral models of acne vulgaris lesions. RESULTS: Two metrics are used to evaluate the enhancement of acne vulgaris lesions, i.e., contrast improvement factor (CIF) and image contrast normalization (ICN). The proposed algorithm is compared with two other methods. The proposed enhancement algorithm shows better result than both the other methods based on CIF and ICN. In addition, sensitivity and specificity are calculated for the segmentation results. The proposed segmentation method shows higher sensitivity and specificity than other methods. CONCLUSION: This article specifically discusses the contrast enhancement and segmentation for automated diagnosis system of acne vulgaris lesions. The results are promising that can be used for further classification of acne vulgaris lesions for final grading of the lesions.

Low prevalence of Cryptosporidium parvum in hospitalized children in Kota Bharu, Malaysia.

The aim of this prospective study was to determine the prevalence of Cryptosporidium parvum in hospitalized children in Kota Bharu, Malaysia. Over a 19 month study period, 258 stool samples were examined from 159 children; 109 with diarrhea and 50 controls without diarrhea. Modified Ziehl-Neelsen staining method and a polymerase chain reaction (PCR) assay were used to detect C. parvum and the samples were also examined for the presence of other intestinal parasites. Only 1 of the 109 (0.9%) children with acute diarrhea was positive for C. parvum by microscopy and PCR. Thirty-one percent of children were infested with other intestinal parasites, the most common being Ascaris lumbricoides and Trichuris trichiura. In conclusion, we found C. parvum to be an uncommon infective agent in hospitalized children with or without diarrhea in Kota Bharu, Malaysia.

A comparative study of MR imaging profile of titanium pedicle screws.

OBJECTIVE: We compared the MR imaging profile of three different types of titanium pedicle screw implants in common usage in a human cadaveric model. We additionally compared the change in temperature during imaging among three constructs. MATERIAL AND METHODS: Titanium-based lumbar pedicle screw/rod constructs from three manufacturers were implanted sequentially in a human cadaveric spine. MR imaging was then performed using both conventional spin-echo sequences and advanced imaging pulse sequences. Changes in tissue temperature were also measured during imaging to assess differences among the various implants. MR images were compared in a blinded fashion by two neuroradiologists. RESULTS: No significant differences in imaging profile were noted between the three types of titanium implants with regards to their MR artifact profile. Fast spin-echo sequences led to a decrease in perceptible MR artifacts. Moreover, there were no significant differences in temperature increase among the three manufacturers (mean increase 0.5 degrees C) during imaging. CONCLUSION: Slight differences in the percentage of titanium among the three pedicle screw systems does not appear to result in artifact differences during MR imaging. Therefore, with regard to imaging profile considerations, the three systems studied should be considered interchangeable.

Chronic relapsing homologous collagen-induced arthritis in DBA/1 mice as a model for testing disease-modifying and remission-inducing therapies.

OBJECTIVE: To test whether the chronic relapsing arthritis induced by immunizing DBA/1 mice with homologous type II collagen is a valuable model for testing disease-modifying antiarthritic drugs. METHODS: Six-week-old male DBA/1 mice were immunized with murine type II collagen in Freund's complete adjuvant, resulting in a chronic relapsing polyarthritis in >80% of the mice 4 weeks after immunization. At the onset of clinical arthritis, mice were treated for 4 weeks with different treatments, including anti-tumor necrosis factor (anti-TNF) and antiinterleukin-12 (anti-IL-12) antibodies, salbutamol, or indomethacin. Alternatively, treatment was administered as a pulse at the beginning of clinical arthritis. Pulse treatments tested included anti-CD3 in combination with anti-TNF, anti-TNF alone, and anti-CD4, either alone or in combination with anti-TNF. After 4 weeks of arthritis, mice were killed and hind paws were assessed histologically for joint damage. RESULTS: Anti-TNF and salbutamol both suppressed clinical arthritis more effectively than indomethacin and, moreover, protected the joints from damage, whereas indomethacin did not. Anti-IL-12 treatment initiated after the onset of clinical symptoms accelerated disease. Pulse therapy with anti-CD3 plus anti-TNF was found to induce remission, clinically as well as histologically, whereas a pulse with either anti-CD4, anti-TNF, or the combination of anti-CD4 plus anti-TNF was less effective. CONCLUSION: Chronic relapsing homologous collagen-induced arthritis is a valuable model for identifying remission-inducing antiarthritic drugs and has predictive value with respect to their joint-protective potency.

Typhoid fever in Malaysian children.

A prospective study of 102 children with bacteriologically confirmed typhoid fever, admitted to Hospital Universiti Sains Malaysia over 5 years was conducted. The average age at presentation was 91.3 (range 6 - 159) months. Fever (900%), abdominal pain (56%) and diarrhoea (44%) were common symptoms. Findings included: hepatomegaly (85.3%), splenomegaly (27.5%), anaemia (31%), leukopenia (15%). thrombocytopenia (26%), positive Widal (62.5%) and Typhidot test (96%). Patients were treated with ampicillin (n = 54) or chloramphenicol (n = 49) and 1/3 developed complications like hepatitis (n = 19), bone marrow suppression (n = 8) and paralytic ileus (n = 7). A patient with splenomegaly, thrombocytopenia or leukopenia was at higher risk of developing complications.

The nonpsychoactive cannabis constituent cannabidiol is an oral anti-arthritic therapeutic in murine collagen-induced arthritis.

The therapeutic potential of cannabidiol (CBD), the major nonpsychoactive component of cannabis, was explored in murine collagen-induced arthritis (CIA). CIA was elicited by immunizing DBA/1 mice with type II collagen (CII) in complete Freund's adjuvant. The CII used was either bovine or murine, resulting in classical acute CIA or in chronic relapsing CIA, respectively. CBD was administered after onset of clinical symptoms, and in both models of arthritis the treatment effectively blocked progression of arthritis. CBD was equally effective when administered i.p. or orally. The dose dependency showed a bell-shaped curve, with an optimal effect at 5 mg/kg per day i.p. or 25 mg/kg per day orally. Clinical improvement was associated with protection of the joints against severe damage. Ex vivo, draining lymph node cells from CBD-treated mice showed a diminished CII-specific proliferation and IFN-gamma production, as well as a decreased release of tumor necrosis factor by knee synovial cells. In vitro effects of CBD included a dose-dependent suppression of lymphocyte proliferation, both mitogen-stimulated and antigen-specific, and the blockade of the Zymosan-triggered reactive oxygen burst by peritoneal granulocytes. It also was found that CBD administration was capable of blocking the lipopolysaccharide-induced rise in serum tumor necrosis factor in C57/BL mice. Taken together, these data show that CBD, through its combined immunosuppressive and anti-inflammatory actions, has a potent anti-arthritic effect in CIA.

Clinical experience of medical students at university sains malaysia.

Experience of acute medical, surgical conditions, and clinical procedures of undergraduate students were assessed via a questionnaire survey during the final week of the 1993/1998 programme at the School of Medical Sciences, Univestiti Sains Malaysia. Individual performances were assessed by a scoring system. One hundred and twenty four students responded, (response rate 97%). More than 90% had seen myocardial infarction, cerebrovascular accident, pneumonia, respiratory distress, gastroenteritis, coma, and snake bite. Less than 33% had witnessed acute psychosis, diabetic ketoacidosis, acute hepatic failure, status epilepticus, near drowning, hypertensive encephalopathy, acute haemolysis or child abuse.Acute surgical/obstetrics cases, seen by >90% students, included fracture of long bones, head injury, acute abdominal pain, malpresentation and foetal distress. Less than 33% had observed epistaxis, sudden loss of vision, peritonitis or burns. Among operations only herniorrhaphy, Caesarian section, internal fixation of fracture and cataract extraction were seen by >80% students. The main deficits in clinical procedures are in rectal and vaginal examinations, urine collection and microscopic examinations. The performance of individual students, assessed by a scoring system, showed 15 students had unacceptably low scores (<149/230, 50%), 37 had good scores (>181.4/230, 70%) and 5 had superior scores (197.6/230, 80%).

The beta2-adrenergic agonist salbutamol is a potent suppressor of established collagen-induced arthritis: mechanisms of action.

The therapeutic potential of salbutamol, a beta2-adrenergic agonist, was explored in collagen-induced arthritis. This study was based on a report that salbutamol, by elevating intracellular cAMP, inhibits IL-12 production by macrophages and dendritic cells, thus preventing Th1 development. Ten-week-old male DBA/1 mice were immunized by intradermal injection of type II collagen in CFA. Arthritis developed 15-30 days later and the mice were treated after onset of disease with salbutamol, 200 microgram i.p. After 10 days, the mice were sacrificed, and the hind paws were evaluated histologically. Salbutamol, 200 microgram daily or every other day, had a profound therapeutic effect on the clinical progression of arthritis, as assessed by clinical score and paw thickness. The therapeutic effect was dose dependent. Daily administration of 200 microgram of salbutamol offered the best protection against joint damage, as assessed by histology. In vitro, salbutamol reduced IL-12 and TNF-alpha release by peritoneal macrophages in a dose-dependent manner, as well as TNF release by synovial cells from arthritic mice. Ex vivo, draining lymph node cells of the salbutamol-treated arthritic mice showed a diminished CII-specific IFN-gamma production and proliferation. In vivo, salbutamol specifically blocked mast cell degranulation in joint tissues. In conclusion, salbutamol has important effects on the immunoinflammatory response and a significant therapeutic action in collagen-induced arthritis.

Susceptibility pattern of Streptococcus pneumoniae among pre-school children in Kota Bharu, Malaysia.

Streptococcus pneumoniae (S. pneumoniae) is the most common bacterial cause of pneumonia, meningitis, and otitis media, with the highest incidence among young children and the elderly. S. pneumoniae was once routinely susceptible to penicillin, but since the mid-1980s the incidence of resistance to penicillin and other antimicrobial agents has been increasing all over the world. To optimize empirical regimens and initial therapy for S. pneumoniae infections, clinical healthcare providers must be informed about the prevalence and pattern of drug resistance among the isolates in their communities. No such data are available for the Malaysian population. Therefore, this study was designed to determine the antibiotic susceptibility pattern of S. pneumoniae among colonized pre-school children in Kota Bharu, Malaysia. Pharyngeal swabs were collected from children 1 month to 6 years of age. S. pneumoniae isolates were identified according to the standard and tested for penicillin resistance with a 1-microgram oxacillin disk by the Kirby-Bauer disk diffusion methods. Of 355 nasopharyngeal specimens obtained from kindergarten students, in-patients and pediatric clinics over a period of 1 year, S. pneumoniae was isolated from 36 (10 per cent). All isolates, except one, were susceptible to penicillin. The resistant isolates was susceptible to erythromycin, chloramphenicol and cephalosporins.

Meta-analysis of the long-term effect of nifedipine for pulmonary hypertension.

BACKGROUND: Pulmonary hypertensive disorders generally result in a progressively worsening course associated with substantial morbidity and mortality. Nifedipine therapy may provide an effective solution to attenuate the disease state. OBJECTIVE: To assess the magnitude and consistency of the effect of nifedipine on reducing pulmonary artery pressure in patients with pulmonary hypertensive disorders. DESIGN: A meta-analysis of 8 trials of nifedipine therapy. METHODS: Clinical trials were identified by a computerized literature search of MEDLINE and by an assessment of bibliographies of retrieved studies. Trials were selected if they measured the change in pulmonary artery pressures in their subjects after weeks to months of therapy. Eight of 25 conducted trials were selected for review. RESULTS: Meta-analysis of 6 homogeneous trials demonstrated a significant decrease in pulmonary artery pressure: -7 mm Hg (95% confidence interval, -3 to -11 mm Hg; P < .01). Heterogeneity of trial results appeared to be due to differences in the severity of initial pulmonary artery pressures and to differences in the dosage of nifedipine rather than the type of disease state. CONCLUSIONS: Meta-analysis of the trials of nifedipine therapy in patients with pulmonary hypertension demonstrated a decrease in pulmonary artery pressure that was associated with an amelioration of clinical symptoms. Because of the paucity of data, however, larger trials are needed to better define its clinical value.

Kawasaki disease in Malaysia.

We report seven cases of Kawasaki disease (KD) who were admitted to Hospital University Sains Malaysia over a period of 8 years. The average age at the time of admission was 29.4 months and four of the children were boys. Five children had all six criteria for diagnosis. Ileus was present in three, and hydrops of the gall bladder and pneumonia in two each, but coronary artery dilatation was seen in only one patient. We also review all the cases of KD reported so far from Malaysia and compare the epidemiological data, clinical course and laboratory findings of the Malaysian patients with those from other parts of the world. The epidemiological and clinical features of Malaysians with KD differ from those seen in Singapore and Japan, but are similar to those seen in Thailand, Australia and North America. The incidence of cardiac complications is low in Malaysians.

Neonatal septic arthritis.

Neonatal septic arthritis has always been considered as separate from its counterpart in older children. The condition is uncommon but serious. Affected neonates usually survive, but with permanent skeletal deformities. Ten cases of neonatal septic arthritis were diagnosed between January 1989 and December 1993 in the neonatal intensive care units of two referral hospitals in the state of Kelantan, Malaysia. All except one neonate was born prematurely. The mean age of presentation was 15.6 days. Joint swelling (10/10), increased warmth (7/10) and erythema of the overlying skin (7/10) were the common presenting signs. Vague constitutional symptoms preceded the definitive signs of septic arthritis in all cases. The total white cell counts were raised with shift to the left. The knee (60%) was not commonly affected, followed by the hip (13%) and ankle (13%). Three neonates had multiple joint involvement. Coexistence of arthritis with osteomyelitis was observed in seven neonates. The commonest organism isolated was methicillin resistant Staphylococcus aureus (9/10). Needle aspiration was performed in nine neonates and one had incision with drainage. Follow up data was available for five neonates and two of these had skeletal morbidity. Early diagnosis by frequent examination of the joints, prompt treatment and control of nosocomial infection are important for management.

Misidentification of toxigenic Corynebacterium diphtheriae as a Corynebacterium species with low virulence in a child with endocarditis.

A 6-year-old boy presented to a university hospital in Malaysia with infective endocarditis complicating cyanotic congenital heart disease. Blood cultures showed a gram-positive, aerobic, coryneform-like bacillus identified by the hospital laboratory as Corynebacterium xerosis, but a reference laboratory identified the organism as a toxigenic strain of Corynebacterium diphtheriae. The two laboratories concurred on all biochemical test results except for sucrose fermentation.

Type b Haemophilus influenzae endocarditis in children: case report and review of the literature.

Haemophilus influenzae type b (Hib) endocarditis is a rare but potentially lethal condition. Only ten cases have been reported in the English literature. This report describes an 8-month-old Malay child with a ventricular septal defect who developed Hib endocarditis and died after 4 weeks of hospitalization. The literature is reviewed and previously reported cases summarized.

Acinetobacter endocarditis in children: a case report and review of the literature.

Acinetobacter calcoaceticus, a gram-negative bacterium ubiquitous in soil, water and sewage, is a rare cause of endocarditis in children. The first case of Acinetobacter endocarditis in an infant is described. This patient had underlying tetralogy of Fallot with absent pulmonary valve. A review of the literature in English revealed only four other cases of Acinetobacter endocarditis in children; three of whom had underlying congenital heart disease. Like the other reported cases, this patient responded well to antibiotic treatment. Subsequently this patient underwent corrective cardiac surgery but died of post-operative complications.