Effect of the myostatin locus on muscle mass and intramuscular fat content in a cross between mouse lines selected for hypermuscularity.

BACKGROUND: This study is aimed at the analysis of genetic and physiological effects of myostatin on economically relevant meat quality traits in a genetic background of high muscularity. For this purpose, we generated G(3) populations of reciprocal crosses between the two hypermuscular mouse lines BMMI866, which carries a myostatin mutation and is lean, and BMMI806, which has high intramuscular and body fat content. To assess the relationship between muscle mass, body composition and muscle quality traits, we also analysed intramuscular fat content (IMF), water holding capacity (WHC), and additional physiological parameters in M. quadriceps and M. longissimus in 308 G(3)-animals. RESULTS: We found that individuals with larger muscles have significantly lower total body fat (r = -0.28) and IMF (r = -0.64), and in females, a lower WHC (r = -0.35). In males, higher muscle mass was also significantly correlated with higher glycogen contents (r = 0.2) and lower carcass pH-values 24 hours after dissection (r = -0.19). Linkage analyses confirmed the influence of the myostatin mutation on higher lean mass (1.35 g), reduced body fat content (-1.15%), and lower IMF in M. longissimus (-0.13%) and M. quadriceps (-0.07%). No effect was found for WHC. A large proportion of variation of intramuscular fat content of the M. longissimus at the myostatin locus could be explained by sex (23%) and direction-of-cross effects (26%). The effects were higher in males (+0.41%). An additional locus with negative over-dominance effects on total fat mass (-0.55 g) was identified on chromosome 16 at 94 Mb (86-94 Mb) which concurs with fat related QTL in syntenic regions on SSC13 in pigs and BTA1 in cattle. CONCLUSION: The data shows QTL effects on mouse muscle that are similar to those previously observed in livestock, supporting the mouse model. New information from the mouse model helps to describe variation in meat quantity and quality, and thus contribute to research in livestock.

Are antibiotics necessary after lower third molar removal?

OBJECTIVE: Patients (n = 110) free of antibiotics, operated on by 3 surgeons ranging in clinical experiences, were evaluated for infection. STUDY DESIGN: In the preoperative period and during the second and seventh postoperative days, the following parameters were analyzed: pain, infection, swelling, trismus, body temperature, C-reactive protein levels (CRP), and salivary neutrophil counts (SNC). During surgery, the following parameters were analyzed: systolic, diastolic, and mean arterial pressure; oximetry; heart rate; anesthesia quality; local anesthetic amount; bleeding; surgery difficulty; and surgery duration. RESULTS: There were some differences in the surgery duration, local anesthetic amount, anesthesia quality, bleeding, pain experienced, trismus, CRP, and SNC, and no changes in hemodynamic parameters, rescue analgesic medication, wound healing, swelling, body temperature, confirmed case of dry socket, or any other type of local infection. Particularly, no systemic infections were found after lower third molar removal (LTMR). CONCLUSIONS: This study suggests that antibiotic prescriptions are unnecessary after LTMR when preoperative infections are absent.

Sublingual ketorolac and sublingual piroxicam are equally effective for postoperative pain, trismus, and swelling management in lower third molar removal.

OBJECTIVE: Lower third molar removal provides a clinical model for studying analgesic drugs. The present study's aim was to compare the clinical efficacy of sublingual ketorolac and sublingual piroxicam in managing pain, trismus and swelling after lower third molar extraction in adult volunteers. STUDY DESIGN: In this double-blinded, randomized, crossover investigation, 47 volunteers received for 4 days ketorolac sublingually (10 mg 4 times daily) and piroxicam sublingually (20 mg once daily) during 2 separate appointments after lower third molar extraction of symmetrically positioned lower third molars. A surgeon evaluated objective parameters (surgery duration, mouth opening, rescue analgesic medication, and facial swelling) and volunteers documented subjective parameters (postoperative pain and global evaluation), comparing postoperative results for a total of 7 days after surgery. The means of the objective and subjective parameters were compared for statistical significance (P < .05). RESULTS: Volunteers reported low pain scores during the postoperative period when treated with either sublingual ketorolac or piroxicam. Also, volunteers ingested similar amounts of analgesic rescue medication (paracetamol) when they received either drug sublingually (P > .05). Additionally, values for mouth openings measured just before surgery and immediately after suture removal 7 days later were similar among volunteers (P > .05), and the type of nonsteroidal antiinflammatory drug (NSAID) used in this study showed no significant differences between swellings on the second or seventh days after surgery (P > .05). CONCLUSIONS: Pain, trismus, and swelling after lower third molar extraction, independent of surgical difficulty, were successfully controlled by sublingual ketorolac (10 mg 4 times daily) or sublingual piroxicam (20 mg once daily), and no significant differences were observed between the NSAIDs evaluated.

Genetic mapping and developmental timing of transmission ratio distortion in a mouse interspecific backcross.

BACKGROUND: Transmission ratio distortion (TRD), defined as statistically significant deviation from expected 1:1 Mendelian ratios of allele inheritance, results in a reduction of the expected progeny of a given genotype. Since TRD is a common occurrence within interspecific crosses, a mouse interspecific backcross was used to genetically map regions showing TRD, and a developmental analysis was performed to identify the timing of allele loss. RESULTS: Three independent events of statistically significant deviation from the expected 50:50 Mendelian inheritance ratios were observed in an interspecific backcross between the Mus musculus A/J and the Mus spretus SPRET/EiJ inbred strains. At weaning M. musculus alleles are preferentially inherited on Chromosome (Chr) 7, while M. spretus alleles are preferentially inherited on Chrs 10 and 11. Furthermore, alleles on Chr 3 modify the TRD on Chr 11. All TRD loci detected at weaning were present in Mendelian ratios at mid-gestation and at birth. CONCLUSIONS: Given that Mendelian ratios of inheritance are observed for Chr 7, 10 and 11 during development and at birth, the underlying causes for the interspecific TRD events are the differential post-natal survival of pups with specific genotypes. These results are consistent with the TRD mechanism being deviation from Mendelian inheritance rather than meiotic drive or segregation distortion.

A comparison of the clinical anesthetic efficacy of 4% articaine and 0.5% bupivacaine (both with 1:200,000 epinephrine) for lower third molar removal.

OBJECTIVE: This study compared the clinical efficacy of 4% articaine (A200) and 0.5% bupivacaine (B200), both with 1:200,000 epinephrine, for lower third molar removal. STUDY DESIGN: Fifty patients underwent removal of symmetrically positioned lower third molars, in 2 separate appointments, under local anesthesia either with A200 or B200, in a double-blind, randomized, and crossover manner. Time to onset, duration of postoperative analgesia, duration of anesthetic action on soft tissues, intraoperative bleeding, and hemodynamic parameters were evaluated. RESULTS: A statistically significant difference between the time to onset of A200 (1.66 +/- 0.13 minutes) and B200 (2.51 +/- 0.21 minutes) was found (P < .05). There was no statistically significant difference in the duration of analgesia, whether the patient was subjected to osteotomy or not, regardless of the local anesthetic used (3 to 4 hours; P > .05). However, when patients received B200 they experienced a statistically significant longer period of anesthesia on the soft tissues as compared with when they had received A200 (around 5 hours and 4 hours, respectively, P < .05). The surgeon's rating of intraoperative bleeding was considered very close to minimal for both anesthetics. In the surgeries with osteotomy, the comparison between A200 and B200 showed statistically significant differences in the diastolic (64 mm Hg and 68 mm Hg, respectively, P = .001) and mean arterial pressure (86 mm Hg and 89 mm Hg, respectively, P = .031) when data from all the surgical phases were pooled. Additionally, the mouth opening at the suture removal was statistically different for A200 and B200 solutions (91.90% +/- 3.00% and 88.57% +/- 2.38% of the preoperative measure, respectively) when surgeries required bone removal (P < .05). CONCLUSIONS: In comparison with 0.5% bupivacaine, 4% articaine (both with 1:200,000 epinephrine) provided a shorter time to onset and comparable hemostasis and postoperative pain control with a shorter duration of soft tissue anesthesia in lower third molar removal.

Epinephrine concentration (1:100,000 or 1:200,000) does not affect the clinical efficacy of 4% articaine for lower third molar removal: a double-blind, randomized, crossover study.

PURPOSE: This study compared the use of 4% articaine in association with 1:100,000 (10 mug/mL; A100) or 1:200,000 (5 mug/mL; A200) epinephrine in lower third molar removal. PATIENTS AND METHODS: Fifty healthy volunteers underwent removal of symmetrically positioned lower third molars, in 2 separate appointments, under local anesthesia with either A100 or A200, in a double-blind, randomized, and crossed manner. Latency, duration of postoperative analgesia, duration of anesthetic action on soft tissues, intraoperative bleeding, and hemodynamic parameters were evaluated. RESULTS: A100 and A200 presented very similar latency (1.64 +/- 0.08 and 1.58 +/- 0.08 minutes, respectively; P > .05). Identical volumes of both anesthetic solutions were used: 2.7 mL = 108 mg of articaine plus 27 mug (A100) or 13.5 mug (A200) of epinephrine. The 2 solutions provided similar duration of postoperative analgesia regardless of bone removal (around 200 minutes; P > .05). The 2 solutions also had a similar duration of anesthetic action on soft tissues (around 250 minutes; P > .05). The surgeon's rating of intraoperative bleeding was considered very close to minimal. Transient changes in hemodynamic parameters were observed, but these were neither clinically significant nor attributable to the type of anesthetic used (P > .05). CONCLUSIONS: An epinephrine concentration of 1:100,000 or 1:200,000 in 4% articaine solution does not affect the clinical efficacy of this local anesthetic. It is possible to successfully use the 4% articaine formulation with a lower concentration of epinephrine (1:200,000 or 5 mug/mL) for lower third molar extraction with or without bone removal.

Articaine and mepivacaine efficacy in postoperative analgesia for lower third molar removal: a double-blind, randomized, crossover study.

OBJECTIVE: Comparison of the clinical efficacy of 4% articaine in relation to 2% mepivacaine, both with 1:100,000 epinephrine, in the prevention of postoperative pain after lower third molar removal. STUDY DESIGN: Twenty patients underwent removal of bilateral lower third molars under local anesthesia (articaine or mepivacaine) in 2 separate appointments, in a double-blind, randomized, and crossed manner. Objective and subjective parameters were recorded for paired comparison of postoperative courses. RESULTS: Duration of analgesia provided by articaine and mepivacaine was 198.00 +/- 25.86, and 125.40 +/- 13.96 min, respectively (P = .02), whereas the duration of anesthesia was 273.80 +/- 15.94 and 216.85 +/- 20.15 min, respectively (P = .06). Both solutions exerted no important effects upon arterial pressure, heart rate, or oxygen saturation (P > .05). CONCLUSIONS: Articaine provides a longer period of analgesic effect and a tendency for a longer period of anesthesia as compared to mepivacaine. The presence of a vasoconstrictor agent in local anesthetic solutions does not seem to influence hemodynamic parameters during lower third molar removal in healthy subjects.

[Epidemiologic features of congestive heart failure. Retrospective analysis of 2561 hospitalizations]. / Aspectos epidemiológicos da insuficiência cardíaca congestiva. Análise retrospectiva de 2561 internamentos.

OBJECTIVES: The aim of this study was to characterise the epidemiology of congestive heart failure namely assessing demographic, etiologic and prognostic aspects, and the hospital admission trends in the last 6 years. METHODS: Retrospective analysis of computerised data concerning patients with congestive heart failure admitted to the department of Internal Medicine. LOCATION: A central hospital in the North of Portugal. SUBJECTS: Two thousand five hundred and sixty-one patients older than 10 years, admitted to the Internal Medicine Department of a central hospital in the North of Portugal between January 1, 1989 and December 31, 1994 and discharged with the principal or first listed diagnosis of congestive heart failure (ICD-9-CM code 4280). RESULTS: Eighty per cent of the patients had more than 60 years of age and the mean age was 69 years (female: 70.40 +/- 12.65; male: 66.24 +/- 12.25; p < 0.0001). Fifty-four per cent were females and 46 per cent males. The prevalence of congestive heart failure in the Internal Medicine Department was 4.8%. Between the ages of 15 and 44 years the hospital age-specific prevalence was between 16.1/10,000/year and 26.7/10,000/year for women and between 14.5/10,000/year and 16.1/10,000/year for men. For ages equal or greater than 75 years it was between 508.9/10,000/year and 561.3/10,000/year for women and between 300.2/10,000/year and 421.8/10,000/year for men. Possible causes of congestive heart failure were: valve disease in 26 per cent of patients, coronary artery disease in 24 per cent and hypertension in 20 per cent. The average case-fatality rate was 15.15% (female: 15.54%; male: 14.69%; chi 2 = 0.36; p > 0.55) evolving from 19.45% in 1989 to 12.59% in 1994 (chi 2 = 6.85; p < 0.01). Between the ages of 15 and 44 years the hospital cause-specific mortality rate was 16.2/100,000 and for ages equal or greater than 75 years it was 743.6/100,000. Stepwise logistic regression produced the following odds ratios for the variables significantly associated with dead during hospital admission: age (> or = 70 years)--1.48; infectious diseases--1.37; central nervous system diseases--2.28; chronic renal diseases--1.96; cardiac arrest--24.1; pulmonary embolism--2.26; acute renal failure--7.93; clinical signs of severe sodium and water retention--1.49; hyponatremia--3.39; other electrolyte abnormalities and acid-base balance disturbances--1.78. The simple linear regression of daily admissions on time produced a positive slope of 0.0002 (p < 0.002). CONCLUSIONS: The hospital prevalence of congestive heart failure is identical to other Western countries and is greater among the elderly patients. Valve disease, coronary artery disease and hypertension are the most frequent causes of congestive heart failure. An increasing trend in hospital admissions for congestive heart failure was observed. The hospital mortality was reduced in the last 6 years and was greater among the elderly patients. Age (> or = 70 years), the presence of comorbidity (infectious disease, central nervous system disease, acute renal failure, chronic renal disease and pulmonary embolism), hyponatremia, other electrolyte abnormalities and acid-base balance disturbances, resuscitated cardiac arrest and the presence of severe sodium and water retention have prognostic significance.

[Infectious endocarditis. A form of the presentation of Marfan's syndrome--a clinical case]. / Endocardite infecciosa. Forma de apresentação da síndrome de Marfan--caso clínico.

The Marfan syndrome is a heritable disease with an autosomal dominant inheritance. Its prevalence is four to six per 100,000 people. It appears to be caused by mutations in a single fibrillin gene on chromosome 15. In its classic form, the Marfan syndrome is associated with abnormalities of the eye, aorta, skeleton, lungs and central nervous system. We describe a case of Marfan syndrome, previously undiagnosed, admitted to the hospital because of persistent fever, caused by an infective endocarditis followed by an acute aortic regurgitation. The purpose of this paper is to increase the awareness of this disorder among clinicians in order to prevent the potentially lethal complications, mostly cardiovascular, that could be avoided by a correct management.

Effects of chronic alcohol consumption and withdrawal on the somatostatin-immunoreactive neurons of the rat hippocampal dentate hilus.

Previous studies have demonstrated that the dentate granule and the CA3 pyramidal cells of the rat hippocampal formation are neuronal populations vulnerable to the toxic effects of ethanol. It also has been shown that the resulting alterations do not end after withdrawal from ethanol. As the neurons in the dentate hilus are heavily interconnected with the dentate granule cells, the authors decided to examine the fate of the hilar neurons after chronic alcohol consumption and withdrawal, inasmuch as the hilar somatostatin-immunoreactive (SS-I) neurons were found to be sensitive to cerebral ischemia and to seizures. The following groups of adult rats were studied: (1) alcohol-fed for 6 and 12 months; (2) alcohol-fed for 6 months and then switched to water for a further 6 months; (3) pair-fed controls; and (4) controls fed ad libitum. The authors determined the numerical density of hilar neurons and the number of its SS-I subpopulation. These were found to be significantly reduced in both the alcohol-fed and withdrawal groups when compared with the respective age-matched controls. The consequent loss of the integrative action of the hilar neurons, including the SS-Is, could explain some of the alcohol-related functional deficits as well as their persistence after withdrawal.