Influence of Maternal Corn Supplementation of Beef Cattle on Muscle Fiber Type and Meat Quality of their Offspring

ObjectivesTo determine the influence of corn supplementation of beef cows during winter and their impact on offspring beef quality attributes.Materials and MethodsForty-seven multiparous Angus beef cows carrying male calves were assigned randomly to two dietary treatments: corn supplementation at 0.2% BW (SUP; n = 24) vs. non-supplementation (NSUP; n = 23) at d 110 d of gestation for 22 wks. Ad-libitum access to low-quality forage was provided to both groups. At 7 d post-calving, a muscle biopsy was collected from the longissimus dorsi muscle (LD) of each calf for muscle fiber typing. Offspring were managed as a single group from nursing through to the backgrounding phase. Thereafter, the steers were placed in the feedlot and assigned to 4 pens (blocks) based on BW and offered ad-libitum access to a 100% corn silage-based ration (76.97% TDN, 11.07% CP), salt and minerals. When the steers reached a final BW of 615 kg (∼16 mo of age), they were slaughtered in a commercial abattoir. A second LD muscle biopsy sample was obtained at 45 min postmortem (PM) for muscle fiber typing. At 96 h PM, striploins (n = 42) were collected, aged for 14 d and samples obtained for Warner Bratzler shear force (WBSF), proximal composition, myofibril fragmentation index (MFI), collagen analysis and objective color evaluation. Data were analyzed as a randomized block design.ResultsImmunofluorescent analysis for the myosin heavy chain (MHC) isoform on the proportion of the fiber type or fiber dimensions was not influenced by maternal dietary treatment at both ages (P > 0.05). However, regardless of maternal dietary treatment, the proportion of fiber type IIA decreased while type IIAX increased in samples from steers at 16 mo of age compared with samples from steers at 7 d of age. No differences were observed between dietary treatment groups in proximate composition (P = 0.8), MFI (P = 0.29), or collagen content (P 0.98); however, WBSF values tended to be higher in steers from SUP cows than steers from NSUP dams (P = 0.07). Maternal dietary treatment had no influence on objective color evaluation at the retail display (P > 0.05). Objectives traits were not affected by dietary treatment × display time interaction (P = 0.92).ConclusionOur findings indicate that corn supplementation of cows during mid to late gestation has minimal effects on muscle fiber type and beef quality of their offspring. Thus, corn supplementation of low-quality forage offered during mid to late gestation did not have detrimental effects on muscle fibers and meat quality of offspring.

Carbohydrate catabolic flexibility in the mammalian intestinal commensal Lactobacillus ruminis revealed by fermentation studies aligned to genome annotations

BACKGROUND

Lactobacillus ruminis is a poorly characterized member of the Lactobacillus salivarius clade that is part of the intestinal microbiota of pigs, humans and other mammals. Its variable abundance in human and animals may be linked to historical changes over time and geographical differences in dietary intake of complex carbohydrates.

RESULTS

In this study, we investigated the ability of nine L. ruminis strains of human and bovine origin to utilize fifty carbohydrates including simple sugars, oligosaccharides, and prebiotic polysaccharides. The growth patterns were compared with metabolic pathways predicted by annotation of a high quality draft genome sequence of ATCC 25644 (human isolate) and the complete genome of ATCC 27782 (bovine isolate). All of the strains tested utilized prebiotics including fructooligosaccharides (FOS), soybean-oligosaccharides (SOS) and 1,3:1,4-β-D-gluco-oligosaccharides to varying degrees. Six strains isolated from humans utilized FOS-enriched inulin, as well as FOS. In contrast, three strains isolated from cows grew poorly in FOS-supplemented medium. In general, carbohydrate utilisation patterns were strain-dependent and also varied depending on the degree of polymerisation or complexity of structure. Six putative operons were identified in the genome of the human isolate ATCC 25644 for the transport and utilisation of the prebiotics FOS, galacto-oligosaccharides (GOS), SOS, and 1,3:1,4-β-D-Gluco-oligosaccharides. One of these comprised a novel FOS utilisation operon with predicted capacity to degrade chicory-derived FOS. However, only three of these operons were identified in the ATCC 27782 genome that might account for the utilisation of only SOS and 1,3:1,4-β-D-Gluco-oligosaccharides.

CONCLUSIONS

This study has provided definitive genome-based evidence to support the fermentation patterns of nine strains of Lactobacillus ruminis, and has linked it to gene distribution patterns in strains from different sources. Furthermore, the study has identified prebiotic carbohydrates with the potential to promote L. ruminis growth in vivo.

The relationship between sources and functions of social support and dimensions of child- and parent-related stress

BACKGROUND

In this longitudinal study, we examined the relationship between the sources and functions of social support and dimensions of child- and parent-related stress for mothers of young children with mild developmental delays.

METHODS

Sixty-three mothers completed assessments of stress and support at two time points.

RESULTS

Multiple regression analyses revealed that parenting support during the early childhood period (i.e. advice on problems specific to their child and assistance with child care responsibilities), irrespective of source, consistently predicted most dimensions of parent stress assessed during the early elementary years and contributed unique variance. General support (i.e. primarily emotional support and validation) from various sources had other, less widespread effects on parental stress.

CONCLUSIONS

The multidimensional perspective of the construct of social support that emerged suggested mechanisms mediating the relationship between support and stress and provided a framework for intervention.

Consistency in regional trends of aggressiveness in cancer care near the end of life for elderly Americans, 1991–2000

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Background: We have previously developed and reported on performance measures assessing the aggressiveness of cancer treatment near the end of life for selected cancers during 1993–96. Methods: We compared the care delivered in the 77 Health Care Service Areas (HCSAs) monitored by the Surveillance, Epidemiology, and End Results (SEER) program to all Medicare-eligible patients aged 65 and over who died of cancer (any diagnosis) between 1991 and 2000. We used hierarchical regression models to estimate regional variation in both levels and trends of each indicator. We then ranked each region according to the model-estimated rate of each indicator and computed the correlation among relative ranks of each region over the ten-year study period. Results: 215,488 patients met eligibility criteria. Within this broader and more recent sample we confirmed previous observations of steadily and significantly increasing use of chemotherapy within 2 weeks of death, emergency room visits, and intensive care unit admissions in the last month of life, and, among those admitted to hospice, an increasing proportion of late admissions within 3 days of death. There was significant regional variation in all measures, but the relative rankings of health care service areas from one year to the next were stable, with correlations of ranks ranging from .91–.98 from 1991–1992, and .66–.84 over the 5-year span from 1991–1995. Because of significant regional variation in trends, we found only moderate correlations ranging from .40–.61 over the entire decade. Conclusions: Cancer treatment near the end of life continued to become increasingly aggressive over the 1990s, however, there was significant regional variation in trends. The stability of regional practice patterns supports the reliability of these measures for quality surveillance purposes.

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No significant financial relationships to disclose.

Guidelines for the use of EEG methodology in the diagnosis of epilepsy. International League Against Epilepsy: commission report. Commission on European Affairs: Subcommission on European Guidelines

The Commission of European Affairs of the International League Against Epilepsy published 'Appropriate Standards for Epilepsy Care Across Europe' which contained recommendations for the use of electroencephalography (EEG) in the diagnosis of epilepsy (Brodie et al. Epilepsia 1997; 38:1245). The need for a more specific basic document of EEG methodology was recognized and the Subcommission on European Affairs was asked to produce more detailed guidelines to be used across Europe recognizing the range of practices in EEG laboratories. There are many general guidelines published on EEG methodology but this document focuses on the diagnosis of epilepsy. Details from previously published guidelines are included in references and in an appendix. These guidelines are not meant to be used as minimal standards but recommendations that can be applied to all EEG laboratories despite variations in equipment.

Acetylcholine receptor delta subunit mutations underlie a fast-channel myasthenic syndrome and arthrogryposis multiplex congenita

Limitation of movement during fetal development may lead to multiple joint contractures in the neonate, termed arthrogryposis multiplex congenita. Neuromuscular disorders are among the many different causes of reduced fetal movement. Many congenital myasthenic syndromes (CMSs) are due to mutations of the adult-specific epsilon subunit of the acetylcholine receptor (AChR), and, thus, functional deficits do not arise until late in gestation. However, an earlier effect on the fetus might be predicted with some defects of other AChR subunits. We studied a child who presented at birth with joint contractures and was subsequently found to have a CMS. Mutational screening revealed heteroallelic mutation within the AChR delta subunit gene, delta 756ins2 and delta E59K. Expression studies demonstrate that delta 756ins2 is a null mutation. By contrast, both fetal and adult AChR containing delta E59K have shorter than normal channel activations that predict fast decay of endplate currents. Thus, delta E59K causes dysfunction of fetal as well as the adult AChR and would explain the presence of joint contractures on the basis of reduced fetal movement. This is the first report of the association of AChR gene mutations with arthrogryposis multiplex congenita. It is probable that mutations that severely disrupt function of fetal AChR will underlie additional cases.

The significance of bilateral EEG abnormalities before and after hemispherectomy in children with unilateral major hemisphere lesions

The rate of seizure relief following hemispherectomy varies between 50 and more than 80%. There has been particular debate concerning the significance of bilateral electroencephalography (EEG) abnormalities in influencing prognosis. This study was set out to determine the frequency of bilateral EEG abnormalities and their relationship to underlying pathology and outcome. We investigated 28 children with unilateral hemisphere lesions, who underwent hemispherectomy. Interictal and ictal EEGs before and after hemispherectomy were reviewed. Post-operative outcome with respect to seizures was noted. Bilateral EEG abnormalities were seen in 75%, but were more common in children with malformations of cortical development than in patients with acquired cerebral lesions, and were found more often in interictal than in ictal records. Post-operative EEG abnormalities were variable and did not consistently predict outcome. Short-term outcome was similar, irrespective of aetiology. With longer term follow-up, only 47% of children with developmental abnormalities were still seizure-free in contrast to 77% of children with acquired abnormalities. Although the incidence of bilateral EEG abnormalities in patients with major unilateral hemisphere lesions is high, these findings alone should not preclude further consideration for hemispherectomy. Our findings emphasise that the aetiology of the lesion plays a major role in determining outcome.

Necrosis in benign salivary gland neoplasms. Not necessarily a sign of malignant transformation

Necrosis that occurs in a salivary gland neoplasm is usually considered to be an ominous sign, suggesting malignant transformation, particularly in lesions that have had no prior manipulation such as fine-needle aspiration. We describe five pleomorphic adenomas and two canalicular adenomas of salivary gland origin that exhibited necrosis, yet were otherwise benign. All lesions displayed a distinctive histopathologic pattern characterized by a narrow rim of viable tumor tissue at the periphery of the neoplasm combined with a diffuse central region that demonstrated apparent ischemic necrosis. No invasion of adjacent normal tissue was identified, and no recurrence or metastasis has been seen with these lesions. Caution should be exercised in the evaluation of salivary gland neoplasms with central necrosis to avoid misdiagnosis of all such lesions as malignant.

Leiomyosarcoma metastatic to the oral region. Report of three cases

Leiomyosarcoma, a malignant lesion of smooth muscle origin, is rare in the oral region. Metastatic leiomyosarcoma may originate from several potential primary sites, and the lung is the most common target tissue for metastatic deposits. This article describes three cases of leiomyosarcoma that were metastatic to the oral cavity and discusses the clinical and histopathologic differential diagnosis.

Carcinoma arising in an odontogenic keratocyst with orbital invasion

A 54-year-old black female presented with proptosis and reduced visual acuity of the left eye. Computerized tomography (CT) revealed tumor involvement of the left cavernous sinus and posterior orbit. The patient had a nineteen year history of a left-sided jaw tumor which recurred despite surgical and radiation therapy. Biopsy demonstrated a parakeratinized odontogenic keratocyst with areas of transformation into an invasive squamous cell carcinoma. Although a parakeratinized odontogenic keratocyst may be locally invasive, to our knowledge, no case of a parakeratinized odontogenic keratocyst involving the orbit or cavernous sinus previously has been reported.

The Noonan syndrome/cherubism association

Noonan syndrome is characterized by short stature, unusual facies, congenital heart disease, chest deformity, mild mental retardation, and cryptorchidism in males. It may be sporadic or inherited as an autosomal dominant trait and occurs between 1 in 1000 and 1 in 2500 live births. Cherubism is a giant cell lesion of the jaws thought to be transmitted as an autosomal dominant trait. It is usually recognized by age 7 years, follows a variable course, and is not known to be related to other genetic disorders. We herein report on four patients with Noonan syndrome, all of whom had cherubism. Two other probable cases are cited in the literature for a total of six known cases.

White sponge nevus. Diagnosis by light microscopic and ultrastructural cytology

The lesions of white sponge nevus, an autosomal dominant abnormality of squamous epithelial differentiation that primarily affects the oral cavity, may be grossly similar to those of other hereditary mucosal syndromes, infections or preneoplastic/neoplastic processes. This differential diagnosis is best resolved in many cases by exfoliative cytology, interpreted in the context of clinical history and physical findings. The following report describes a case of white sponge nevus with typical clinical and cytologic findings, in which the diagnosis was confirmed by ultrastructural cytology. Light microscopic cytology revealed parakeratotic cells and many cells containing dense eosinophilic intracytoplasmic inclusions. Electron micrographs of exfoliated cells demonstrated that these inclusions are composed of disordered aggregates of tonofilaments.

The verruciform xanthoma. A review and report of eight new cases

The verruciform xanthoma (VX) is an uncommon lesion that most often occurs in the oral cavity but occasionally may be seen in other sites. Eight new cases of VX of the oral mucosa are presented. The histologic features are discussed and theories of etiology and pathogenesis are reviewed. The VX appears to be a reactive lesion in which the xanthoma cells arise secondarily to degeneration of cells in the overlying epithelium.

Two cases of X/autosome translocation in females with incontinentia pigmenti

We report two unrelated girls who present some clinical features of severe incontinentia pigmenti (IP), with characteristic skin pigmentation. Both have balanced de novo X/autosome translocations involving band Xp11. The coincidence of the probable de novo expression of an X-linked disorder in these two girls with translocations involving similar breakpoints on the X chromosome suggests that this band may be the site of the IP gene locus.