Intrauterine position affects motoneuron number and muscle size in a sexually dimorphic neuromuscular system

The intrauterine position occupied by a rodent fetus influences the amount of testosterone to which it is exposed before birth. Animals that are gestated between two male fetuses (2M) are exposed to higher circulating levels of testosterone than are animals positioned between two female fetuses (2F) and there are reliable differences in the reproductive physiology and behavior of 2M and 2F animals when adult. To determine whether intrauterine position modifies development of the central nervous system, we examined the sexually dimorphic spinal nucleus of the bulbocavernosus (SNB) in male and female gerbils from known intrauterine positions. We found that adult 2M female gerbils had 16% more SNB motoneurons than did 2F females. 2M males did not differ from 2F males in SNB motoneuron number, but the bulbocavernosus muscle, which is innervated by SNB motoneurons, was approximately 50% larger in 2M than in 2F males. These data indicate that intrauterine position can influence the morphology of the sexually dimorphic SNB neuromuscular system.     

Health insurance and private providers: A study of the civil servants' medical benefit scheme in bangkok,Thailand

Compulsory health insurance schemes have received attention recently as a means of creating a reliable extra-budgetary source of health care funding. Yet, the full implications of such schemes in a developing country context are unclear; in particular, the impact on and relationship with private sector providers has infrequently been explored. This study examines patterns of public and private sector utilization under the Civil Servants' Medical Benefit Scheme (CSMBS) in Bangkok, Thailand. The CSMBS currently provides limited reimbursement for private inpatient care, but recent proposals suggest increasing benefit levels for care sought in the private sector. The study shows that despite high level of cost recovery in the public sector, charges were much lower than those in the private sector. Different patterns of diagnosis in the two sectors were found with private hospitals tending to treat a less complex case mix. Within the private sector, there was a limited tendency to specialize in certain types of care. It is concluded that under the current payment mechanism of fee-for-service reimbursement, measures to enhance access to private sector care should be approached with caution. In the long run, the scheme should merge with the recently established social security scheme.     

Adjustments to the mantel–haenszel test for data from stratified multistage surveys

The usual form of the Mantel–Haenszel test statistic assumes independent observations. This is inappropriate for data from a stratified multistage survey. Two alternative adjustments to the test statistic are developed to deal with this: (a) a modification of the effective sample size for each row of each table, using the design effects, extending a method proposed by Donald and Donner for familial aggregation studies; (b) a Taylor series approximation to the variance of the square root of the numerator of the Mantel-Haenszel statistic. Both methods are evaluated by application to both simulated and real data. The two methods perform equally well, and offer a considerable improvement over the unadjusted test statistic when observations from the same cluster are highly correlated. A simplified adjustment is also considered, as is the need for correction to the variance of the odds ratio estimator.     

Regional haemodynamic effects of human and rat adrenomedullin in conscious rats.

1. Male, Long Evans rats were chronically instrumented with pulsed Doppler flow probes and intravascular catheters to permit assessment of the regional haemodynamic responses to human and rat adrenomedullin, to compare the responses to human adrenomedullin to those of human alpha-CGRP in the absence and presence of the CGRP1-receptor antagonist, human alpha-CGRP [8-37], and to determine the involvement of nitric oxide (NO)-mediated mechanisms in the responses to human adrenomedullin, relative to human alpha-CGRP. 2. Human and rat adrenomedullin (0.3, 1, and 3 nmol kg-1, i.v.) caused dose-dependent hypotension and tachycardia, accompanied by increases in renal, mesenteric and hindquarters flows and vascular conductances. At the lowest dose only, the hypotensive and mesenteric vasodilator effects of rat adrenomedullin were significantly greater than those of human adrenomedullin. 3. Human alpha-CGRP at a dose of 1 nmol kg-1 caused hypotension, tachycardia and increases in hindquarters flow and vascular conductance, but reduction in renal and mesenteric flows, and only transient vasodilatations in these vascular beds. These effects were substantially inhibited by human alpha-CGRP [8-37] (100 nmol kg-1 min-1), but those of human adrenomedullin (1 nmol kg-1) were not; indeed, the mesenteric haemodynamic effects of the latter peptide were enhanced by the CGRP1-receptor antagonist. 4. In the presence of the NO synthase inhibitor, NG-nitro-L-arginine methyl ester (L-NAME, 183 nmol kg-1 min-1), there was only a slight, but significant, inhibition of the hindquarters hyperaemic vasodilator effect of human adrenomedullin, but not that of human alpha-CGRP.(ABSTRACT TRUNCATED AT 250 WORDS)     

Vaccination of Lewis rats with temperature-sensitive mutants of Mycoplasma pulmonis: adoptive transfer of immunity by spleen cells but not by sera.

Temperature-sensitive mutant vaccines protect rats against Mycoplasma pulmonis infection. The role of the humoral or cellular immune response in resistance to mycoplasma infection was investigated by adoptive-transfer experiments. Spleen cells from Lewis rats vaccinated but not challenged with wild-type organisms (vaccinated) and spleen cells from rats vaccinated (or not) and challenged were effective in preventing syngeneic recipients from developing respiratory disease. There was also a significant reduction in the incidence and number of challenging organisms in the respiratory system. In contrast, sera from the same donors had no detectable effect on the number of mycoplasmas recovered or on lesion development in the respiratory tract. We conclude that cellular immunity rather than humoral immunity generated in vaccinated rats confers protection against subsequent infection.     

Sequential occurrence of IgA nephropathy and Henoch-Schönlein purpura: support for common pathogenesis

We report a patient who developed Henoch-Schönlein purpura (HSP) 13 years after he presented with IgA nephropathy (IgAN). In both HSP and IgAN renal biopsy most commonly reveals focal proliferative glomerulonephritis on light microscopy and immunofluorescence displays mesangial IgA deposits. In addition, patients with HSP or IgAN have elevated serum IgA levels, circulating IgA immune complexes, IgA-bearing lymphocytes, immunoglobulin-producing cells, and binding of IgG to glomerular components of similar molecular weight. The occurrence of both diseases in the same patient or the same families and the presence of immune abnormalities compatible with HSP or IgAN in relatives of patients with these diseases suggest a common pathogenesis.     

Difficult or Impossible Ventilation after Sufentanil-induced Anesthesia Is Caused Primarily by Vocal Cord Closure

Introduction: Opioid-induced rigidity often makes bag-mask ventilation difficult or impossible during induction of anesthesia. Difficult ventilation may result from chest wall rigidity, upper airway closure, or both. This study further defines the contribution of vocal cord closure to this phenomenon.

Methods: With institutional review board approval, 30 patients undergoing elective cardiac surgery participated in the study. Morphine (0.1 mg/kg) and scopolamine (6 micro gram/kg) given intramuscularly provided sedation along with intravenous midazolam as needed. Lidocaine 10% spray provided topical anesthesia of the oropharynx. A fiberoptic bronchoscope positioned in the airway photographed the glottis before induction of anesthesia. A second photograph was obtained after induction with 3 micro gram/kg sufentanil administered during a period of 2 min. A mechanical ventilator provided 10 ml/kg breaths at 10/min via mask and oral airway with jaw thrust. A side-stream spirometer captured objective pulmonary compliance data. Subjective airway compliance was scored. Pancuronium (0.1 mg/kg) provided muscle relaxation. One minute after the muscle relaxant was given, a third photograph was taken and compliance measurements and scores were repeated. Photographs were scored in a random, blinded manner by one investigator. Wilcoxon signed rank tests compared groups, with Bonferroni correction. Differences were considered significant at P <0.05.

Results: Twenty-eight of 30 patients exhibited decreased pulmonary compliance and closed vocal cords after opioid induction. Two patients with neither objective nor subjective changes in pulmonary compliance had open vocal cords after opioid administration. Both subjective and objective compliances increased from severely compromised values after narcotic-induced anesthesia to normal values (P = 0.000002) after patients received a relaxant. Photo scores document open cords before induction, progressing to closed cords after the opioid (P = 0.00002), and opening again after a relaxant was administered (P = 0.00005).     

IDENTIFICATION OF NEURODEVELOPMENTAL ABNORMALITY AT FOUR AND EIGHT MONTHS BY THE MOVEMENT ASSESSMENT OF INFANTS

The predictive validity of infant neuromotor evaluation by the Movement Assessment of Infants (MAI) was investigated in low-birthweight infants. Motor performance at four and eight months was examined in relation to neurodevelopmental outcome at 18 months of age. Correlations were equally strong between total MAI risk scores at four and eight months and performance on the Bayley Scales. Muscle tone observations were more discriminating at four months, and automatic reactions and volitional movement were most predictive at eight months. The MAI was highly sensitive to neurodevelopmental abnormality at four and eight months and more sensitive than the Bayley Motor Scale; both assessment tools had lower specificity at eight months. The high false-positive rate is attributed to transient neuromotor abnormalities and immaturity of motor function in low-birthweight infants with normal outcome.