Exercise during rat pregnancy and lactation: maternal effects and offspring growth

Eighty Sprague-Dawley rats were divided into exercised (E) and sedentary (S) groups. E rats were trained to run on a treadmill (30 m/min, 2 hr/day). Within each group, two subgroups were mated and three served as virgin time controls. Of the mated subgroups, one was terminated within 24 hours of delivery and the other on day 14 of lactation. Subgroups of virgin S and E controls were terminated at times corresponding to the mating, delivery and lactation day 14 of mated rats. MANOVA revealed that exercise significantly affected food intake, body weight and body composition in both virgin and mated animals: generally, E rats ate more, gained more weight, and had less carcass fat than S controls. E rats did not store fat during pregnancy. At parturition, they were 7.0% fat, similar to both E (6.6%) and S (7.6%) controls prior to mating, and less than S rats at parturition (11.9%). Despite diminished fat stores at parturition in E rats, litter size and pup birthweight were similar in E and S rats, as was offspring growth during lactation (mean weights on day 14 of 28.9 g and 29.3 g, respectively). Remaining body fat and increased food intake were adequate to support normal pup growth.     

Relationships between striatal dopamine denervation and frontal executive tests in Parkinson's disease

Indirect evidence from human and monkey investigations supports the idea that impaired frontal tasks in Parkinson's disease (PD) may result from striato-frontal disruption caused by dopamine (DA) denervation of the caudate nucleus. To directly investigate this hypothesis, we used PET with 11C-S-Nomifensine (11C-S-NMF), a sensitive marker of striatal DA denervation, in 10 non-demented PD patients in whom two frontal executive tests, the object alternation (OA) and the conditional associative learning (CAL) tasks, thought to reflect mainly set-shifting/inhibition and planning, respectively, were given. In addition, the central executive function of verbal working memory was assessed with the Brown Peterson paradigm (BPP). We found a highly significant correlation between right caudate 11C-S-NMF specific binding and OA performance, less significant and reverse-direction correlations between CAL performance and putamen 11C-S-NMF binding, and no significant correlation with BPP performance. Thus, caudate DA denervation may subtend poor set-shifting/inhibition process in PD. Our results also point to distinct and complex relationships between striatal DA and specific frontal tasks.     

Hemolytic uremic syndrome with hypocomplementemia, serum C3NeF, and glomerular deposits of C3

A 4-year-old boy had hemolytic uremic syndrome (HUS) associated with depression of serum C3 level, a B-hemolytic streptococcal throat infection, and an elevated level of antistreptolysin O titer. In addition to the characteristic histologic changes associated with this syndrome, substantial infiltration of polymorphonuclear leukocytes and nodular deposits of C3 globulin were seen in the glomeruli of the first biopsy specimen. Two months after clinical remission, he had a recurrence of hemolytic anemia, thrombocytopenia, and acute renal failure. The serum C3 concentration had decreased again, and serum C3NeF was detected in the serum. The typical changes associated with HUS were still present on electron microscopy. Bilateral nephrectomy and renal transplantation were done because of the development of uncontrollable severe hypertension and increasing azotemia. This patient had three manifestations of HUS, but because of several differences, such as hypocomplementemia, serum C3NeF, a recurrence, and persistent glomerular deposits of C3 globulin, he appears to have had a different form of the syndrome.     

Unidirectional block in a computer model of partially coupled segments of cardiac Purkinje tissue

The initiation of a reentrant circuit requires a zone of slow conduction and a zone of unidirectional block. This study used computer model conditions under which partial coupling between segments of cardiac Purkinje tissue resulted in unidirectional block. The structure used was one-dimensional and divided into three segments: a middle segment of variable length coupled to two long (semi-infinite in concept) segments. The DiFrancesco-Noble equations represented the ionic currents of the membrane. The results show that the possibility of unidirectional block depends on the size of the middle segment and the coupling resistances between the segments. No combination of coupling resistances allowed unidirectional block for middle segments with a length of two space constants (4 mm) or longer. Unidirectional block occurred for many combinations of coupling resistances as the length of the middle segment decreased to around half a space constant (1 mm). The number of length combinations that caused unidirectional block decreased again as segment length further decreased. These results provide a possible mechanism of unidirectional block for situations where islands of viable tissue are connected through nonviable tissue, such as in a healed myocardial infarction.     

An influenza A(H3) reassortant was epidemic in Australia and New Zealand in 2003

During 2003, Australia and New Zealand experienced substantial outbreaks of influenza. The strain responsible was an A(H3N2) influenza virus described as A/Fujian/411/2002-like, which had circulated as a minor variant in the previous Northern Hemisphere (NH) winter, mainly in Korea and Japan. Early in the year the isolates were very similar to those that had been previously isolated in the NH, however, a reassortant strain emerged early in the New Zealand winter, followed by the appearance of similar viruses in Australia and other regional areas. While the hemagglutinin HA1 sequence of these viruses demonstrated only minor differences from the A/Fujian/411/2002 reference strain, the neuraminidase gene was clearly different from that of other recently circulating H3 viruses and most closely matched an earlier reference strain A/Chile/6416/2001. Three internal genes (NS, NP, M) in the reassortant viruses were also more closely related to the A/Chile/6416/2001 lineage. This reassortant A(H3) virus predominated in Australia and New Zealand in 2003 was also seen in Brazil and Malaysia during 2003 and was widespread in the United States and Europe during their 2003-04 winter. Interestingly most of the strains of A(H3) that were isolated at the beginning of the 2004 winter in Australia, did not have this earlier A/Chile/6416/2001-like neuraminidase but had a neuraminidase that was similar to that of the reference strain A/Fujian/411/2002. This was suggestive of the re-introduction of influenza A(H3) from other countries, however, there was still low level circulation of the reassortant virus in 2004 with isolates detected in Australia and Singapore.     

Involvement of the catecholaminergic system in glucagon-induced thermogenesis in Muscovy ducklings (Cairina moschata)

Physiological studies have shown that glucagon is a potential mediator of nonshivering thermogenesis (NST) in birds. The present work was undertaken in order to investigate whether the observed thermogenesis results from a direct action of glucagon on avian thermoregulatory mechanisms or in fact requires the participation of other agents such as catecholamines. Our experiments were performed using cold-acclimated (CA) ducklings which developed muscle NST. A comparison was made with thermoneutral (TN) ducklings of the same age. Our principal results showed that: (1) at ambient temperature (25 degrees C), circulating norepinephrine (NE) was markedly decreased in CA ducklings (-42%), while circulating epinephrine (E) did not undergo any consistent change; (2) in CA and TN ducklings, an intraperitoneal injection of glucagon (360 microg x kg(-1)) was followed after 10 min by prominent lipolysis and a large increase in circulating NE (4- to 6-fold) and E (14- to 17-fold), which was sustained for at least 1 h. The elevation of circulating NE was less pronounced in CA ducklings. The thermogenic action of glucagon in birds is probably indirect and involves at least the mobilization of lipids and sympatho-adrenal stimulation. The changes in peripheral noradrenergic activity during cold acclimation could be associated with adaptive changes leading to NST.     

Invasion of the mandible by squamous carcinomas of the oral cavity and oropharynx

The radiologic and histologic features of mandibular invasion, and its clinical implications, are considered in a retrospective series of 111 patients with squamous carcinomas of the oral cavity and oropharynx treated by composite resection. Eighty percent of the entire group had either recurrent or advanced (T3, T4) local disease, and 33 patients (30%) had histologic evidence of mandibular invasion by tumor. Preoperative radiologic assessment was unreliable in cases in which infiltrating tumor was confined to the periosteum and superficial cortex-44% false negatives. The extent of bone invasion was found to correlate with the size of the tumor, but not with its histologic grade. The mandibular periosteum was not seen as a morphologically discrete "barrier" and infiltration occurred at various points along the mandibular body, mainly related to the course of the inferior dental canal. The gross and microscopic patterns of bone invasion appeared to be similar in irradiated and nonirradiated resections. The incidence and pattern of recurrent disease following composite resection was the same in the groups with and without mandibular invasion: in each group half the patients were dead from disease and one third alive and free of disease at 2 years. Mandibular invasion alone did not appear to influence prognosis in this series.     

Androgen levels and androgenization in sex-reversed (XXSxr pseudomale) mouse: absence of initial segment of epididymis is independent of androgens

The XXSxr pseudomale ("sex-reversed") mouse has an apparently normal male phenotype. This is in accordance with Jost's Principle that, in an animal with androgen-producing testes, phenotype will be fully masculinized, irrespective of chromosomal sex. However, the epididymis of this mutant lacks the Initial Segment. Several alternative explanations were proposed. In the present study we examined the primary of these, viz, androgen insufficiency. We studied androgen levels in serum and tissues of the mutant, and we investigated whether injection of exogenous androgens could induce normal development. The XXSxr pseudomale is not deficient in androgens, nor do exogenous additional androgens induce development of the Initial Segment. It would appear that the abnormal genotype acts on the organ phenotype without intervention of androgens.     

Interventions to Increase Multivitamin Use Among Women in the Interconception Period: An IMPLICIT Network Study

Maternal and Child Health Journal - Each year, 3% of infants in the Unites States (US) are born with congenital anomalies, including 3000 with neural tube defects. Multivitamins (MVIs) including...