Stability of motor lateralisation in maturing dogs

Previous studies of motor laterality in dogs have produced some conflicting results, with inconsistencies in lateral biases across sexes, over time, and across tasks. The current study modified published food-retrieval and tape-removal tests before applying them to 43 dogs. It showed that results derived from 50 observations of a food-retrieval task (Kong? test) were consistent with 100 observations. Further, observations during both Kong? and the tape-removal tests were consistent both within and between observers. Lateralisation results from both the Kong? and Tape tests were generally consistent between breeds and sexes and over time, the only exceptions being the categorical groups during the Tape test and the strength of lateralisation in the Kong? test. Of greatest interest in this study was the lack of consistency between results from the two different motor lateralisation tasks conducted. Given that motor lateralisation is said to reflect differences in brain structure or function, differences in task results may indicate differing complexities of the two tasks.     

Screening mammography: a surgeon's strategy for dealing with abnormal mammographic findings

Screening mammography is a valuable tool in the detection of breast cancer at an early stage. Large numbers of patients are being referred to surgeons for biopsies on the basis of mammographic abnormalities alone. As mammograms are complex studies and the findings often subtle, variation in terms of interpretation and recommendations for biopsy can leave the surgeon in a difficult position. We have reported a systematic method for evaluating patients and mammograms. Eighty-eight patients were referred to a single surgeon solely for an abnormal mammographic finding. Physical examination was repeated and the mammogram reviewed with a single consulting radiologist using specific criteria to define a mammographic abnormality. Through this evaluation, biopsy was avoided in 42 of 88 patients, with follow-up mammograms and physical examinations finding no suspicion of malignancy. By becoming educated in regard to mammographic abnormalities, establishing specific criteria with a consistent radiologist, and following patients carefully who are not biopsied, the surgeon can deal effectively with screening mammography.     

Hair Whorls in the Dog (Canis familiaris), Part II: Asymmetries

In horses and cattle, hair whorls have been shown to act as a structural marker of reactivity and behavioral lateralization. Few studies on canine whorls have been reported and none have assessed whorl position or direction of flow. This study describes the distribution and characteristics of whorl in each of 10 regions in which whorls are typically located in dogs. Hair whorls were assessed in dogs (n = 120) and were recorded as clockwise or counterclockwise in the cephalic, cervical (dorsal, lateral, ventral), thoracic and brachial axillary, chest, shoulders, elbows, abdominal, and ischiatic regions. Bilateral whorls, including brachial axillary, elbow, abdominal and ischiatic whorls, rotated in opposing directions, allowing the dog's overall hair coat to be symmetrical. Cephalic, brachial axillary, and ischiatic whorls were consistent in their direction; cephalic and ischiatic whorls were clockwise on the right side of the body, and counterclockwise on the left, whereas right brachial axillary whorls were counterclockwise and left were clockwise. The central chest whorl was predominantly counterclockwise (91.21%). Direction of whorls was associated with several factors, including coat length, coat thickness, sex and source of the dog. Anat Rec, 2010. © 2009 Wiley‐Liss, Inc.     

Clinical breast examination practices among women undergoing screening mammography

In this prospective multicenter study, the authors evaluated the utility of magnetic resonance (MR) cisternography after intrathecal administration of gadopentetate dimeglumine in 15 patients clinically suspected of having cerebrospinal fluid (CSF) rhinorrhea. By means of lumbar puncture, a single dose of 0.5 mL of gadopentetate dimeglumine was injected into the lumbar subarachnoid space. Thirteen patients showed leakage of contrast material through the cribriform plate into the ethmoid or sphenoid air cells. No leakage was observed in two patients. The study results show the relative safety and feasibility of low-dose gadolinium-enhanced MR cisternography in confirming the presence and determining the focus of active CSF leaks.     

The lethal effects of the cibarial and pharyngeal armatures of mosquitoes on microfilariae.

Microfilariae of Wuchereria bancrofti and Brugia pahangi were killed by the chewing action of the cibarial and pharyngeal armatures and other papillae and spines in the fore-gut of mosquitoes. The proportion of ingested microfilariae that were killed was largely dependent on the presence and shape of the cibarial armature. Anopheles farauti No. 1 and Anopheles gambiae species A and B have well developed cibarial armatures and killed 36 to 96% of the ingested microfilariae. Culex pipiens fatigans has a poorly developed cibarial armature and killed only 6% of the microfilariae. Aedes aegypti and Aedes togoi lack cibarial armatures but have the remaining fore-gut structures. They killed only 2 to 22% of the microfilariae. The significance of these observations in relation to the control of filariasis with diethylcarbamazine is discussed.     

A prospective study comparing the complication rates between laparoscopic and open ventral hernia repairs

Background: Although ventral hernia repair is increasingly performed laparoscopically, complication rates with this procedure are not well characterized. For this reason, we performed a prospective study comparing early outcomes after laparoscopic and open ventral hernia repairs. Methods: We identified all the patients undergoing ventral (including incisional) hernia repair at a single tertiary care center between September 1, 1999 and July 1, 2001 (overall n = 257). To increase the homogeneity of the sample, we excluded umbilical hernia repairs, parastomal hernia repairs, nonelective procedures, procedures not involving mesh, and repairs performed concurrently with another surgical procedure. Postoperative complications (in-hospital or within 30-days) were assessed prospectively according to standardized definitions by trained nurse clinicians. Results: Of the 136 ventral hernia repairs that met the study criteria, 65 (48%) were laparoscopic repairs (including 3 conversions to open surgery) and 71 (52%) were open repairs. The patients in the laparoscopic group were more likely to have undergone a prior (failed) ventral hernia repair (40% vs 27%; p = 0.14), but other patient characteristics were similar between the two groups. Overall, fewer complications were experienced by patients undergoing laparoscopic repair (8% vs 21%; p = 0.03). The higher complication rate in the open ventral hernia repair group came from wound infections (8%) and postoperative ileus (4%), neither of which was observed in the patients who underwent laparoscopic repair. The laparoscopic group had longer operating room times (2.2 vs 1.7 h; p = 0.001), and there was a nonsignificant trend toward shorter hospital stays with laparoscopic repair (1.1 vs 1.5 days; p = 0.10). Conclusions: The patients undergoing laparoscopic repair had fewer postoperative complications than those receiving open repair. Wound infections and postoperative ileus accounted for the higher complication rates in the open ventral hernia repair group. Otherwise, these groups were very similar. Long-term studies assessing hernia recurrence rates will be required to help determine the optimal approach to ventral hernia repair. Drs. Birkmeyer and Finlayson were supported by Career Development Awards from the VA Health Services Research and Development program. The views expressed herein do not necessarily represent the views of the Department of Veterans Affairs or the United States Government.     

Rational preoperative evaluation

Clinical data from two hundred consecutive patients undergoing surgical procedures at the Salt Lake City VA Hospital form the basis of this study. Results of nine commonly ordered preoperative tests (blood count, differential, electrolytes, chemistry panel, urinalysis, prothrombin time, partial thromboplastin time, electrocardiogram, and chest X-ray) were matched with the preoperative history and physical examination and the outcome of surgery in each patient. Each test was examined by the frequency with which it was ordered, the frequency with which it was abnormal, and the frequency with which the abnormal result affected preoperative care. A prevalence of medical illness was found in this population, with 47.5% having a major cardiovascular diagnosis, 35.5% a metabolic or endocrine disease, and 28% a major pulmonary diagnosis. A total of 1271 tests were performed, with 477 (35.5%) showing some abnormality. However, only 76 (5.9%) changed the patient's management before surgery. All but five of these abnormalities were predictable from the clinical evaluation and these five were minor. The overall postoperative complication rate was 9%. No complication was attributed to the omission of a preoperative test. No surgical cases were cancelled during the study period based solely on a preoperative test. We conclude that many preoperative tests can be safely eliminated by ordering only those based on a specific abnormality in the history or physical examination, resulting in more cost-effective surgical care.     

Detailed comparison of regional and general anesthesia for carotid endarterectomy

Forty-one variables were examined in 75 patients who underwent carotid endarterectomy to determine if significant differences were present between 45 patients who had general anesthesia and 30 patients who had regional anesthesia. The two groups were similar in terms of age, existing medical illnesses, neurologic presentation, and angiographic severity of the carotid lesions. There were no differences between the two groups for operative time, anesthesia time, blood loss, maximum or minimum blood pressures, postoperative hemodynamic data, or the requirement for or duration of intravenous pressor or antihypertensive medications. One patient in the regional group had a postoperative neurologic deficit which resolved in 1 month. Three patients in the general group had cardiovascular complications. Postoperative hospital stay was significantly longer in the general anesthesia group (5.6 to 3.2 days, p = 0.003). Regional and general anesthesia produce similar perioperative hemodynamic and surgical outcomes, but regional anesthesia results in a shorter hospital stay and less cardiovascular morbidity in this high risk population.     

Comparison of a Saline Irrigated Cooled-Tip Catheter to Large Electrode Catheters with Single and Multiple Temperature Sensors for Creation of Large Radiofrequency Lesions

Background: Several catheter technologies for creating large radiofrequency (RF) lesions are used in clinical practice, but direct comparisons of the pathological lesions created by these technologies are unavailable. The purpose of this study was to compare the safety and efficacy of lesions created by three different large lesion RF ablation technologies. Methods and Results: RF lesions were created in all four chambers of 15 mongrel dogs using 10 mm-tip multiple temperature sensor catheters, 10 mm tip single temperature sensor catheters, and 4 mm cooled-tip catheters. Pathological lesions were bisected, and measured after viability staining. A total of 242 (79 large-tip single sensor, 82 large-tip multiple sensor, and 81 cooled-tip) lesions were created. All atrial lesions were transmural but tended to have larger surface areas with the single thermistor large-tip catheter (73.4 ± 24.8 mm²) compared to either the multithermistor large-tip (60.9 ± 28.3 mm²) or the cooled-tip (61.9 ± 28.5 mm²) catheters (p = 0.07), especially those in the IVC-TA isthmus. Depths and volumes of ventricular lesions created by the multiple-thermistor catheter (5.0 ± 1.5 mm; 260 ± 168 mm³) were smaller than either the single thermistor (5.7 ± 1.5 mm; 428 ± 290 mm³) or cooled-tip (6.1 ± 1.8 mm; 403 ± 217 mm³) catheters (p < 0.05). The difference in the depth and volume of lesions made by large-tip single thermistor and cooled-tip catheters was not significant. Char formation occurred during 11% of ablation with the single thermistor catheter, 6% with multithermistor and 8% of cooled-tip catheter (p = NS). There were no complications of ablation. Conclusions: All three catheters reliably created full thickness atrial lesions. For ventricular lesions, depths and volumes were similar for 10 mm-tip single thermistor and cooled-tip catheters. The multithermistor catheter lesions were smaller due to more precise temperature regulated power control. Safety was similar in all 3 groups.     

Dietary sialic acid supplementation improves learning and memory in piglets

BACKGROUND: Sialic acid, a key component of both human milk oligosaccharides and neural tissues, may be a conditional nutrient during periods of rapid brain growth. OBJECTIVE: We tested the hypothesis that variations in the sialic acid content of a formula milk would influence early learning behavior and gene expression of enzymes involved in sialic acid metabolism in piglets. DESIGN: Piglets (n = 54) were allocated to 1 of 4 groups fed sow milk replacer supplemented with increasing amounts of sialic acid as casein glycomacropeptide for 35 d. Learning performance and memory were assessed with the use of easy and difficult visual cues in an 8-arm radial maze. Brain ganglioside and sialoprotein concentrations and mRNA expression of 2 learning-associated genes (ST8SIA4 and GNE) were measured. RESULTS: In both tests, the supplemented groups learned in significantly fewer trials than did the control group, with a dose-response relation for the difficult task (P = 0.018) but not the easy task. In the hippocampus, significant dose-response relations were observed between amount of sialic acid supplementation and mRNA levels of ST8SIA4 (P = 0.002) and GNE (P = 0.004), corresponding with proportionate increases in protein-bound sialic acid concentrations in the frontal cortex. CONCLUSIONS: Feeding a protein-bound source of sialic acid during early development enhanced learning and increased expression of 2 genes associated with learning in developing piglets. Sialic acid in mammalian milks could play a role in cognitive development.