Using hospitalization for ambulatory care sensitive conditions to measure access to primary health care: an application of spatial structural equation modeling

Background  

In data commonly used for health services research, a number of relevant variables are unobservable. These include population lifestyle and socio-economic status, physician practice behaviors, population tendency to use health care resources, and disease prevalence. These variables may be considered latent constructs of many observed variables. Using health care data from South Carolina, we show an application of spatial structural equation modeling to identify how these latent constructs are associated with access to primary health care, as measured by hospitalizations for ambulatory care sensitive conditions. We applied the confirmatory factor analysis approach, using the Bayesian paradigm, to identify the spatial distribution of these latent factors. We then applied cluster detection tools to identify counties that have a higher probability of hospitalization for each of the twelve adult ambulatory care sensitive conditions, using a multivariate approach that incorporated the correlation structure among the ambulatory care sensitive conditions into the model.     

Seroepidemiology of Rubella in Saudi Arabia

The seroepidemiology of infection due to rubella virus in Saudi Arabia was investigated in various age groups including unvaccinated children (newborn to 15 years of age) using a newer rubella antibody test system, the ELISA with maximum sensitivity and reliability. The assessment of the immune status indicated the lowest level of naturally acquired rubella IgG antibodies in children aged 13-18 months and thereafter a pattern of progressive age-specific increase in seropositivity. About 90 per cent of the women of childbearing age were seroimmune. The target population for rubella immunization is identified.     

Routine Screening of Gynaecological and Obstetric Patients for Chlamydia Trachomatis

Chlamydia trachomatis infection of the cervix uteri was diagnosed in 9% of 221 gynaecological and obstetric patients. Infection occurred more commonly among obstetric (12.6%) than gynaecological patients (5.5%). In obstetric patients chlamydial infection was commoner in those complaining of excessive vaginal discharge or spontaneous premature rupture of the membranes. Chlamydial infection in gynaecological patients occurred in those with previous pelvic infection, menstrual disorders or excessive vaginal discharge. No cases of chlamydial infection were detected among intrauterine device users. The enzyme immunoassay we used is an easy and relatively quick method of diagnosis for genital chlamydial infection.     

Analgesic principle from the bark of Careya arborea

Bioactivity guided isolation of the bark of Careya arborea afforded piperine--an alkaloid chemically known as 1-[5-(1,3-benzodioxol-5-yl)-1-oxo-2,4-pentadienyl]piperidine, which was found to possess significant central and peripheral analgesic activity. At oral doses of 10, 20 and 30 mg/kg body weight, piperine exhibited 41 (p < 0.01), 45 (p < 0.01) and 53% (p < 0.001) inhibition of acetic acid induced writhing in mice respectively. At doses of 20 and 30 mg/kg body weight, the compound also showed 31.8 (p < 0.05) and 52.4% (p < 0.01) prolongation of tail flicking time of mice 30 min after the treatments determined by the radiant heat method.     

Effects of transient loss of shear stress on blood-brain barrier endothelium: role of nitric oxide and IL-6

Loss of blood-brain barrier (BBB) function may contribute to post-ischemic cerebral injury by yet unknown mechanisms. Ischemia is associated with anoxia, aglycemia and loss of flow (i.e. shearing forces). We tested the hypothesis that loss of shear stress alone does not acutely affect BBB function due to a protective cascade of mechanisms involving cytokines and nitric oxide (NO). To determine the relative contribution of shear stress on BBB integrity we used a dynamic in vitro BBB model based on co-culture of rat brain microvascular endothelial cells (RBMEC) and astrocytes. Trans-endothelial electrical resistance (TEER), IL-6 release and NO levels were measured from the lumenal and ablumenal compartments throughout the experiment. Flow-exposed RBMEC were challenged with 1 h of normoxic-normoglycemic flow cessation (NNFC) followed by reperfusion for 2 to 24 h. NNFC caused a progressive drop in nitric oxide production during flow cessation followed by a time-dependent increase in ablumenal IL-6 associated with a prolonged NO increase during reperfusion. The nitric oxide synthetase (NOS) inhibitor L-NAME (10 microM) abrogated all effects of NNFC, including changes in NO and cytokine production. BBB permeability did not increase during or after NNFC/reperfusion, but was increased by treatment with L-NAME or when the effects of IL-6 were blocked. Flow adapted RBMEC and astrocytes respond to NNFC/reperfusion by overproduction of IL-6, possibly secondary to increased production of NO during the reperfusion. Maintenance of BBB function during and following NNFC appears to depend on intact NO signaling and IL-6 release.     

Vertical transmission of dengue: first case report from Bangladesh

We report a case of vertical transmission of dengue infection in a new born from Bangladesh. The mother was primigravida with an uneventful antenatal period except the fever she developed at 37 weeks of gestation. She underwent cesarean section for decreased fetal movement. The fever lasted for 7 days and was associated with intense bodyache, and a positive tourniquet test. She did not experience any hemorrhages including from the surgical wound. Her platelet count fell at its lowest to 100,000/mm3. She had bilateral mild pleural effusions and positive anti-dengue antibodies (both IgG and IgM). She received symptomatic treatment. The baby was deeply meconium stained and was resuscitated by a pediatrician. His postnatal period went well until day-3 of life when he developed fever and respiratory distress. There were no signs of meconiun aspiration syndrome (MAS) and the septic work up was negative. The platelets count fell to its lowest of 40,000/mm3 on day-3 and day-5 of his illness. Anti-dengue antibodies (both IgG and IgM) were positive with a nearly four-fold rise of IgM antibodies in the convalescent sera. The boy was treated with platelet transfusions and was discharged on day-6 after becoming ill. This report emphasizes that in a dengue epidemic or when dengue is endemic (which Bangladesh has experienced recently), a pregnant woman with fever, myalgia and/or bleeding manifestations should raise a high suspicion that the baby may develop the disease, and both the mother and baby should be closely followed-up. Viral isolation could not be done due to the unavailability of the test.     

Changes in plaque fluoride levels by school-based fluoride rinsing and tablet programs in Bangladesh

The aim of this study was to evaluate the effects of school-based fluoride rinsing and tablet programs on plaque fluoride levels. A total of 42 children (8-9 years) were selected from two neighboring schools in Dhaka, Bangladesh. After caries recordings, vestibular plaque samples from the maxillary central incisors and mandibular first molars were collected and frozen on day 0 (baseline). The subjects of one school (rinsing group, n = 15) rinsed with 0.05% NaF, while those from the other school (tablet group, n = 16) used a 0.5 mg F tablet on the 5 school days during a 3-week period. The surfaces were sampled on the first and last school day every week. The fluoride and protein contents of each sample were analyzed using micro-techniques. The median plaque fluoride levels were 9.1 ppm at baseline in the rinsing group and 2.5 ppm in the tablet group (P < 0.05). This difference could in part be related to reported fluoride toothpaste usage. After 4 days on the fluoride programs, plaque fluoride levels in the rinsing group increased to 27.3, 24.5 and 14.2 ppm in the 3 consecutive weeks. The corresponding values after tablet usage were 8.0, 6.5 and 7.1 ppm, respectively. After 3 days without fluoride during the weekends, levels declined towards baseline values in both groups. Hence, the plaque fluoride levels in 8 to 9-year-old Bangladeshi children were increased by both rinsing and tablet programs, but the effect was not detectable 3 days later.     

Delayed presentation of post-traumatic aneurysm of the posterior inferior cerebellar artery in a patient with spinal cord injury

STUDY DESIGN: A case report. OBJECTIVE: To present and discuss the case of a patient with serious head and spinal injuries who suffered delayed haemorrhage from a post-traumatic aneurysm of the right posterior inferior cerebellar artery following surgical treatment of vertebral fracture and hydrocephalus. SETTING: National Spinal Injuries Unit and Institute of Neurological Sciences, Southern General Hospital, Glasgow, Scotland, UK. METHODS: Clinical and radiological follow-up of the patient. RESULTS: The aneurysm was treated by coil occlusion of the right vertebral artery. Post-operative films showed that the aneurysm had been successfully obliterated. CONCLUSION: Post-traumatic cerebral aneurysms are very rare. Neurosurgical and rehabilitation teams need to be aware of this late treatable sequela of head injury.     

Fibroblast growth factors (FGF-1, FGF-2) promote migration and neurite growth of mouse cochlear ganglion cells in vitro: immunohistochemistry and antibody perturbation

To study the effect of FGF in the early development of the sensory neurons of the auditory system, we established a culture preparation of ganglionic neuroblasts engaged in migration and process outgrowth. The presumed anlage of the cochlear ganglion was dissected from E11 otocysts, just as the neuronal precursors were migrating. The cultures were divided into 4 groups and supplemented for 7-9 days with either hrFGF-1 or hrFGF-2 or both or with defined medium only (control group). Measurements of the increase in explant growth, neuroblast migration, and neurite outgrowth were made by time-lapse imaging techniques in living cultures. Either FGF-1 or FGF-2 alone stimulated early migration and outgrowth of the ganglion cells by 5-10x. The effect of combining FGF-1 and FGF-2 was greater than either alone, but less than additive, consistent with a shared receptor. BrdU labeling confirmed that the effect was on migration, not on proliferation. Adding a neutralizing antibody for FGF-2 to the cultures inhibited migration and neurite outgrowth, suggesting an endogenous FGF-2 activity in these functions. Immunocytochemical observations in vitro and in situ with antibodies to FGF-1, FGF-2, or FGF receptor (R1) demonstrated immunopositive staining of the migrating ganglionic neuroblasts, their processes, and growth cones at corresponding stages (E13). Also non-neuronal cells, hair cells, and Schwann cells (in situ) expressed FGF-1 and FGF-2. Evidently both FGF-1 and FGF-2 play important roles in the migration and initial differentiation of cochlear ganglion neurons in the mouse.