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M Macari

Publications and source records attributed to M Macari.

At least 19 recordsLinked to original sources
PubMed2007

CT of jejunal diverticulitis: imaging findings, differential diagnosis, and clinical management.

AIM: To describe the imaging findings of jejunal diverticulitis as depicted at contrast-enhanced computed tomography (CT) and review the differential diagnosis and clinical management. MATERIALS AND METHODS: CT and pathology databases were searched for the diagnosis of jejunal diverticulitis. Three cases were identified and the imaging and clinical findings correlated. RESULTS: Jejunal diverticulitis presents as a focal inflammatory mass involving the proximal small bowel. A trial of medical management with antibiotics may be attempted. Surgical resection may be required if medical management is unsuccessful. CONCLUSION: The imaging findings at MDCT may allow a specific diagnosis of jejunal diverticulitis to be considered and may affect the clinical management of the patient.

Abdomen, Acute↗
PubMed2005

Computer-aided detection (CAD) for CT colonography: a tool to address a growing need.

Colorectal cancer is the third most common cancer in both men and women. It is estimated that in 2004, nearly 147,000 cases of colon and rectal cancer will be diagnosed in the USA, and approximately 57,000 people would die from the disease; however, only 44% of the eligible population undergoes any type of colorectal cancer screening. Many reasons have been identified for non-compliance, with key ones being patient comfort, bowel preparation and cost. Virtual colonoscopy derived from computed tomography (CT) images is gaining broader acceptance as a screening method for colorectal neoplasia. Our research suggests that computer-aided detection (CAD) as a second reader has great potential in improving polyp detection. The ColonCAD prototype presented in this paper was developed and tested on cases representative of the variability and quality in true clinical practice. Results of this study with 150 patients demonstrate that: the developed algorithm generalises well: the sensitivity for polyps > or = 6 mm is on average 90%; and the median false positive rate is a manageable 3 per volume.

Algorithms↗
PubMed2002

Growth hormone mRNA expression in the pituitary of Bos indicus and Bos taurus x Bos indicus crossbred young bulls treated with recombinant bovine somatotropin.

The effects of breed and of recombinant bovine somatotropin (rbST) treatment on growth hormone gene expression were studied in young bulls. The experiment was completely randomized in a [2 x 2]-factorial arrangement, using two levels of rbST (0 or 250 mg/animal/14 days), and two breed groups (Nelore and Simmental x Nelore crossbred). A cDNA encoding Bos indicus growth hormone was cloned and sequenced for use as a probe in Northern and dot blot analyses. Compared to the Bos taurus structural gene, the Bos indicus cDNA was found to begin 21 bases downstream from the transcription initiation site and had only two discrepancies (C to T at position 144-His and T to C at position 354-Phe), without changes in the polypeptide sequence. However, two amino acid substitutions were found for Bubalus spp., which belong to the same tribe. The rbST treatment did not change any of the characteristics evaluated (body and pituitary gland weights, growth hormone mRNA expression level). Crossbred animals had significantly higher body weight and heavier pituitaries than Nelore cattle. Pituitary weight was proportional to body weight in both breed groups. Growth hormone mRNA expression in the pituitary was similar (P>0.075) for both breed and hormonal treatment groups, but was 31.9% higher in the pure Nelore group, suggesting that growth hormone gene transcription regulation differs among these breeds.

Animals↗
PubMed2002

Somatotrophic and thyroid hormones around the onset of lay in broiler breeders under different conditions.

Somatotrophic and thyroid hormones were determined around the onset of reproduction in broiler breeders reared in two different housing systems [dark, close-sided house (CH) and conventional, open-sided house (OH)]. In both groups age-related changes were obvious for thyroxine (T4), growth hormone (GH) and insulin-like growth factor (IGF-1); levels of T4 decreased, especially between 24 and 28 weeks in both groups; concomitantly GH sharply increased over the same period. A transient peak in triiodothyronine (T3) occurred between 25 and 27 weeks. The effect of housing was only present after the onset of lay. Between weeks 27-28 and the end of the period studied, the CH group showed higher levels of GH and T3 but lower T4 levels as compared to the OH group. A significant increase in GH after onset of lay, without any significant rise in T3 or in IGF-I, could point to a relative insensitivity to high plasma GH levels. Changes at GH receptor level, together with an increased pituitary GH secretion and/or decreased GH turnover may be expected. This may indicate that hypothalamo-pituitary changes at the onset of lay not only imply changes of gonadotrophic cell function, but also other hormonal axes. The relatively decrease in T4 without changes in T3, may point to a decrease in the activity of the thyrotropic axis.

Aging↗
PubMed2002

Intestinal starch disappearance increased in steers abomasally infused with starch and protein.

Steers (379 +/- 10 kg) with ruminal, duodenal, and ileal cannulas were used in a 5 x 5 Latin square digestion trial to quantify and evaluate the relationship between intestinal protein supply and intestinal starch disappearance. Treatments were infusions of 0, 50, 100, 150, or 200 g/d of casein along with 1,042 g/d of raw cornstarch. Abomasal infusions were accomplished by passing tubing and a pliable retaining washer through the reticular-omasal orifice into the abomasum. Steers were fed a 93% corn silage, 7% supplement diet that contained 12% crude protein at 1.65% body weight in 12 equal portions/d. Periods lasted 17 d (12 d for adaptation, 2 d of collections, and 3 d of rest). The quantity and percentage of organic matter and protein disappearance from the small intestine increased linearly (P < 0.03) with infused casein. Greater quantities of starch disappeared with increased casein infusion (P < 0.01). The infusion of 200 g/d of casein increased small intestinal starch disappearance by 226 g/d over the control. Casein infusion did not affect the quantity or percent of organic matter, starch, or protein disappearance in the large intestine. Treatments did not change ruminal ammonia N, ruminal pH, or plasma glucose concentrations. Starch disappearance from the small intestine was increased with greater protein flow to the duodenum of steers.

Abomasum↗
PubMed2001

Virtual colonoscopy: clinical results.

CT colonography is an evolving noninvasive imaging technique that allows detection of colorectal polyps and cancers. When assessing the clinical results of this test, several points need to be emphasized. First, as computed tomography (CT) technology improves, so will clinical results. Therefore, earlier results reporting the accuracy of CT colonography may not be applicable to the current state of the art. Second, as clinical experience has grown, an understanding of the limitations and pitfalls of the technique has increased. A learning curve is involved and, with increased experience, results should improve. This article will focus on the evolving clinical results of CT colonography.

Colon↗
PubMed2001

Sodium and chloride requirements of young broiler chickens fed corn-soybean diets (one to twenty-one days of age).

Sodium (Na+) and chloride (Cl-) nutritional requirements, dietary electrolyte balance (DEB), and their effects on acid-base balance, litter moisture, and tibial dyschondroplasia (TD) incidence for young broiler chickens were evaluated in two trials. One-day-old Cobb broilers were distributed in a completely randomized design with six treatments, five replicates, and 50 birds per experimental unit. Treatments used in both experiments were a basal diet with 0.10% Na+ (Experiment 1) or Cl- (Experiment 2) supplemented to result in diets with Na+ or Cl- levels of 0.10, 0.15, 0.20, 0.25, 0.30, or 0.35%, respectively. In Experiment 1, results indicated an optimum Na+ requirement of 0.26%. Sodium levels caused a linear increase in arterial blood gas parameters, indicating an alkalogenic effect of Na+. The hypertrophic area of growth plate in the proximal tibiotarsi decreased with Na+ levels. The TD incidence decreased with increases in dietary Na+. Litter moisture increased linearly with sodium levels. In Experiment 2, the Cl- requirement was estimated as 0.25%. Chloride levels caused a quadratic effect (P < or = 0.01) on blood gas parameters, with an estimated equilibrium [blood base excess (BE) = 0] at 0.30% of dietary Cl-. No Cl- treatment effects (P > or = 0.05) were observed on litter moisture or TD incidence. The best DEB for maximum performance was 298 to 315 mEq/kg in Experiment 1 and 246 to 264 mEq/kg in Experiment 2. We concluded that the Na+ and Cl- requirements for optimum performance of young broiler chickens were 0.28 and 0.25%, respectively.

Acid-Base Equilibrium↗
PubMed2001

Acute appendicitis: comparison of helical CT diagnosis focused technique with oral contrast material versus nonfocused technique with oral and intravenous contrast material.

PURPOSE: To compare the diagnostic accuracy of focused helical computed tomography (CT) with orally administered contrast material with that of nonfocused helical CT with orally and intravenously administered contrast material. MATERIALS AND METHODS: After receiving oral contrast material, 228 patients with clinically suspected appendicitis underwent focused appendiceal CT (5-mm section thickness, 15-cm coverage in the right lower quadrant). Immediately thereafter, helical CT of the entire abdomen and pelvis was performed following intravenous administration of contrast material (abdomen, 7-mm section thickness; pelvis, 5-mm section thickness). Studies were separated and independently interpreted by three observers who were blinded to patient names. Diagnoses were established by means of surgical and/or clinical follow-up findings. RESULTS: Fifty-one (22.4%) of 228 patients had acute appendicitis. Readers diagnosed appendicitis with 83.3%, 73.8%, and 71.4% sensitivity and 93.0%, 92.3%, and 97.9% specificity with focused nonenhanced appendiceal CT. Readers diagnosed appendicitis with 92.9%, 92.9%, and 88.1% sensitivity and 93.7%, 95.1%, and 96.5% specificity with nonfocused enhanced CT. Summary areas under the receiver operating characteristic curve estimates for focused nonenhanced and nonfocused enhanced CT were 0.916 and 0.964, respectively; the differences were statistically significant (P <.05) for two of three readers. All readers demonstrated higher sensitivities for detecting the inflamed appendix with nonfocused enhanced CT. Appendicitis was missed with focused CT in two patients whose inflamed appendix was not included in the imaging of the right lower quadrant. All readers were significantly more confident in diagnosing alternative conditions with nonfocused enhanced CT. CONCLUSION: Diagnostic accuracy of helical CT for acute appendicitis improved significantly with use of intravenous contrast material.

Acute Disease↗
PubMed2001

Effect of different bowel preparations on residual fluid at CT colonography.

The effect of different bowel preparations on residual fluid during computed tomographic (CT) colonography was evaluated. Forty-two patients received either a polyethylene glycol electrolyte solution preparation or a phospho-soda preparation the day prior to CT colonography. The amount of residual fluid was calculated for each patient. On average, a phospho-soda preparation provided significantly less residual fluid than a polyethylene glycol electrolyte solution preparation.

Aged↗
PubMed2001

Infrarenal abdominal aortic aneurysms at multi-detector row CT angiography: intravascular enhancement without a timing acquisition.

In 70 patients referred for evaluation of aortoiliac aneurysm disease, multi-detector row computed tomography was performed with a uniform 25-second delay from the initiation of intravenous administration of a 150-mL bolus of contrast material at 4 mL/sec. In all patients, adequate enhancement (>200 HU) of the aorta and intense enhancement of iliofemoral runoff was achieved without venous contamination.

Aged↗
PubMed2000

Influence of early quantitative food restriction on long bone growth at different environmental temperatures in broiler chickens.

1. This investigation was carried out to study the influence of early quantitative food restriction (40% of ad libitum intake from 7 to 14 d of age) and environmental rearing temperature (thermoneutral, cold and hot) on long bone (tibia, femur and humerus) development in broiler chickens. 2. Tibia, femur and humerus were obtained at the ages of 14, 21, 28, 35 and 42 d, and the variables studied were: length and width (mm, expressed as absolute values), bone breaking strength (kgf) and bone weight/bone length index (BW/BL, mg/mm). 3. All bone variables increased with bird age. Food restriction reduced bone length and width but did not affect bone weight. High environmental rearing temperature reduced bone length and width at 42 d of age. Bone strength was not affected by environmental temperature but the calculated BW/BL index was reduced by heat exposure. 4. The findings suggest that food restriction and high environmental rearing temperature reduce long bone growth; bone breaking strength was affected by bird age but not by food restriction nor rearing ambient temperature.

Animal Husbandry↗
PubMed2000

Comparison of time-efficient CT colonography with two- and three-dimensional colonic evaluation for detecting colorectal polyps.

OBJECTIVE: We compared the findings of time-efficient CT colonography with complete two-dimensional (2D) and three-dimensional (3D) CT colonography and conventional colonoscopy in detecting colorectal polyps. SUBJECTS AND METHODS: Forty-two patients undergoing colonoscopy screening were examined with CT colonography before endoscopy. Data were examined following one of two methods. In method 1, axial 2D data sets were examined in a cine mode. If findings were suggestive of abnormality, focal areas were examined with 3D CT colonography. In method 2, data sets were examined exactly as in method 1, and subsequent to that review, data sets were examined with simultaneous 3D "fly-through" CT colonography (surface-rendered images) and multiplanar reformatted images. The time required to examine CT colonography using each technique was recorded and abnormal findings were documented. Results of methods 1 and 2 were compared with findings on colonoscopy. RESULTS: Colonoscopy detected 16 polyps in 13 patients (polyp size, 2-10 mm). Ten polyps measured 5 mm or less, five measured between 6 and 9 mm, and one measured 10 mm or more. Using method 1, two of 10 polyps measuring less than 5 mm, three of five polyps measuring between 6 and 9 mm, and one polyp measuring 10 mm were detected. We noted no false-positive polyps. Average evaluation time was 16 min. With method 2, the same polyps were seen as with method 1. No additional polyps were detected, and the average evaluation time was 40 min. CONCLUSION: Axial 2D CT colonography can be performed quickly and is comparable with complete 2D and 3D CT colonography in detecting colorectal polyps.

Aged↗
PubMed1999

Hepatic concentration of heat shock protein 70 kD (Hsp70) in broilers subjected to different thermal treatments.

1. The relationship between repeated thermal treatments and hepatic synthesis of Hsp 70 was studied in broiler chickens. 2. Sixty broilers were submitted to 5 different treatments (12 birds each) from day 1 to day 42. Four groups were kept in a thermoneutral environment and subjected to 0, 1, 2 and 3 heat stress episodes at 35 degrees C for 4 h per week (TN-0, TN-1, TN-2 and TN-3, respectively). The last group (HT-35) was reared at a room temperature of 35 degrees C. 3. From 39 to 42 old, the birds experienced acute heat stress at 41 degrees C. Resistance to heat stress was evaluated by the time taken for rectal temperature to increase by 3 degrees C above the pre-treatment value. Livers were collected (before and after heat stress) and Hsp70 was determined using Western Blot analysis with monoclonal anti-Hsp70 antibody. 4. Resistance to heat stress and concentration of Hsp70 were higher in those birds subjected to more heat stress episodes during the experimental period (TN-3) and HT-35. A positive correlation was observed between Hsp70 concentration and the time taken for a 3 degrees C increase in rectal temperature (r = 0.42; P<0.01). 5. Exposing birds to episodes of heat stress (35 degrees C) during rearing may improve their resistance to acute heat stress, but the previous thermal history did not seem to influence the hepatocyte Hsp70 content after exposure to more severe heat stress (41 degrees C).

Analysis of Variance↗
PubMed1999

The accordion sign at CT: a nonspecific finding in patients with colonic edema.

PURPOSE: To determine whether the "accordion sign" is a specific computed tomographic (CT) sign of Clostridium difficile colitis. MATERIALS AND METHODS: Fifty-seven patients with CT evidence of severe colitis, as judged by colonic wall thickening, an abnormal haustral pattern, the target sign, and stranding of the pericolic fat, were identified from a computerized CT database for 25 months. CT images were retrospectively evaluated for the presence of oral contrast material in the colon and for the accordion sign. The medical and laboratory records of all patients were reviewed and correlated with CT findings to establish the cause of colitis. RESULTS: Oral contrast material had reached the colon in 35 of 57 patients at the time of the CT examination. The images in 15 of these patients demonstrated the accordion sign, and those in 20 patients did not. C difficile colitis was documented in four of the 15 cases displaying the accordion sign. In the remaining 11 patients, a different cause was documented. Oral contrast material had not reached the colon in the remaining 22 patients. Within this group with findings similar to the accordion sign, five patients had documented C difficile colitis, and four had colitis from other causes. CONCLUSION: The accordion sign is indicative of severe colonic edema or inflammation, but it is not specific for C difficile colitis.

Adult↗
PubMed1999

Delayed CT to evaluate renal masses incidentally discovered at contrast-enhanced CT: demonstration of vascularity with deenhancement.

PURPOSE: To determine whether delayed computed tomography (CT) can help confirm vascularity in a neoplasm and differentiate it from a high-density cyst when a well-demarcated homogeneous high-attenuating (> 30-HU) renal mass is incidentally discovered during contrast material-enhanced CT. MATERIALS AND METHODS: In 25 patients, 26 well-demarcated, homogeneous high-attenuating renal masses (mean diameter, 2.5 cm; range, 1-4 cm) detected at initial postcontrast CT were further evaluated with delayed CT (mean, 38 minutes; range, 15-240 minutes) performed with identical parameters. On both the initial postcontrast and delayed CT scans, region-of-interest measurements were obtained in renal masses and in the gallbladder or low-density renal cysts as controls. Correlation with surgical or additional imaging findings was used to determine proof of diagnosis. RESULTS: Nine of the masses demonstrated no change in attenuation between initial postcontrast and delayed CT, indicating that they represented avascular lesions consistent with high-density cysts. These cases were confirmed with prior or follow-up imaging studies that demonstrated stability. Seventeen masses (nine surgically proved neoplasms and eight neoplasms that demonstrated interval growth at follow-up or previous CT) demonstrated decreased attenuation at delayed CT compared with initial postcontrast CT, which indicates vascularity. CONCLUSION: Delayed CT of incidentally discovered well-demarcated homogeneous high-attenuating (> 30-HU) renal masses detected at postcontrast CT enables differentiation of high-density cysts from renal neoplasms by demonstrating deenhancement as a proof of vascularity and, hence, neoplasm.

Adult↗