Smoking Habits and the Leukocyte Count

In 86,488 multiphasic examinations, mean leukocyte counts were highest in cigarette smokers, intermediate in ex-cigarette and cigar or pipe smokers, and lowest in nonsmokers. Among the races, whites had the highest, yellows next, and blacks the lowest leukocyte counts. The leukocyte count was related to quantity smoked, inhalation, and smoking duration. Most groups who changed smoking habits showed corresponding changes in leukocyte counts. Higher leukocyte counts in smokers appeared largely to be a direct effect of smoking, although a small part of the increase seemed attributable to chronic bronchitis. A contribution of genetic or constitutional differences between smokers and nonsmokers was not ruled out. “Normal” leukocyte count values should take into account age, sex, race, and smoking status.     

The role of injury discharge in the induction of neuropathic pain behavior in rats.

When sensory fibers are damaged, a discharge of impulses is emitted, which can last up to a few minutes. In the present study, we examined whether this injury discharge plays a role in triggering 'autotomy'--a behavior involving self-injury in animals that is induced by total denervation of a hind paw. Sensory input from the sciatic and saphenous neuroma is thought to elicit chronic pain sensations which cause the rat to injure the hind paw. In the present experiments: (1) injury discharge was prevented by using a local anesthetic block and (2) injury discharge was artificially prolonged by delivering 150 electrical pulses to the nerve just prior to transection, at a strength sufficient to drive A- and C-fibers. In one group of animals, the nerve was stimulated at 0.5 Hz at which frequency a synchronous, repetitive activity in C-fibers augments the response of some nociceptive dorsal horn neurons by temporal summation ('wind-up'). In 2 other groups, the sciatic nerve was stimulated at 0.1 Hz and 10 Hz. The results show that blocking injury discharge significantly delayed the average time of onset of autotomy and suppressed it in magnitude compared to control rats. In contrast, electrical stimulation, especially at the 'wind-up' frequency, significantly shortened the onset of autotomy and enhanced its severity. Thus, in spite of its short duration, injury discharge affects the subsequent development of neuropathic pain related behavior.     

Balloon angioplasty enhances the expression of angiotensin II AT1 receptors in neointima of rat aorta.

Angiotensin II is a vasoactive peptide and may act as a growth factor in vascular smooth muscle cells. Experimental injury of the rat aorta causes rapid migration of medial smooth muscle cells and their proliferation resulting in the formation of neointima. We have examined, using quantitative autoradiography, the expression of angiotensin II receptor subtypes AT1 and AT2, and angiotensin-converting enzyme, in the neointima formed in the rat thoracic aorta 15 d after balloon-catheter injury. In contrast to the normal aortic wall, which contained both AT1 and AT2 receptors (80% and 20%, respectively), neointimal cells expressed almost exclusively angiotensin II AT1 receptors. The apparent number of these receptors was fourfold higher in the neointima compared to that in the normal aortic wall. The affinities of the neointimal receptors to angiotensin II or to the AT1 receptor antagonist, losartan, were not different from those in the normal aortic wall. Angiotensin-converting enzyme binding in the neointima was not different from that in the media of the uninjured aorta. Our data suggest that angiotensin II AT1 receptors may have a significant role in injury-induced vascular smooth muscle proliferation and migration.     

Short-term outcomes of a program developed to inculcate research essentials in undergraduate medical students

Background:

Participation in research during undergraduate studies may increase students’ interest in research and inculcate research essentials in them.

Aims:

The purpose of this study was to evaluate the effectiveness of the mentored student project (MSP) program.

Settings and Design:

In the MSP program, students in groups (n = 3 to 5) undertook a research project, wrote a scholarly report, and presented the work as a poster presentation with the help of a faculty mentor. To begin with, the logic model of the program was developed to identify short-term outcomes of the program on students, mentors, and the institution. A quasi-experimental design was used to measure the outcomes.

Materials and Methods:

A mixed method evaluation was done using a newly-developed questionnaire to assess the impact of the MSP on students’ attitude, a multiple-choice question (MCQs) test to find out the impact on students’ knowledge and grading of students’ project reports and posters along with a survey to check the impact on skills. Students’ satisfaction regarding the program and mentors’ perceptions were collected using questionnaires. Evidence for validity was collected for all the instruments used for the evaluation.

Statistical Analysis:

Non-parametric tests were used to analyze data. Based on the scores, project reports and posters were graded into A (>70% marks), B (60-69% marks), and C (<59% marks) categories. The number of MSPs that resulted in publications, conference presentation and departmental collaborations were taken as impact on the institution.

Results:

Students’ response rate was 91.5%. The students’ attitudes regarding research changed positively (P = 0.036) and score in the MCQ test improved (P < 0.001) after undertaking MSP. Majority of project reports and posters were of grade A category. The majority of the items related to skills gained and satisfaction had a median score of 4. The MSPs resulted in inter-departmental and inter-institutional collaborations, 14 publications and 15 conference presentations. An area for improvement noted was to have the MSP implemented in the curriculum without increasing students’ overall workload and stress.

Conclusion:

The study identified strengths and weaknesses of the MSP program. Our model of undergraduate research project may be incorporated in undergraduate medical programs to foster positive attitude and knowledge base about scientific research and to instil research skills among students.KEY WORDS: Attitude, knowledge, mentored, outcome, research, skills, student     

Measurements and standards for bulk-explosives detection

Recent years have seen a dramatic expansion in the application of radiation and isotopes to security screening. This has been driven primarily by increased incidents involving improvised explosive devices as well as their ease of assembly and leveraged disruption of transportation and commerce. With global expenditures for security-screening systems in the hundreds of billions of dollars, there is a pressing need to develop, apply, and harmonize standards for x-ray and gamma-ray screening systems used to detect explosives and other contraband. The National Institute of Standards and Technology has been facilitating the development of standard measurement tools that can be used to gauge the technical performance (imaging quality) and radiation safety of systems used to screen luggage, persons, vehicles, cargo, and left-behind objects. After a review of this new suite of national standard test methods, test objects, and radiation-measurement protocols, we highlight some of the technical trends that are enhancing the revision of baseline standards. Finally we advocate a more intentional use of technical-performance standards by security stakeholders and outline the advantages this would accrue.     

Colon cancer metastatic to a urachus diagnosed by PET/CT

A 50-year-old man presented with a mass in the transverse colon diagnosed by colonoscopy. He underwent a left hemicolectomy and was diagnosed with a moderately differentiated adenocarcinoma penetrating into the pericolic adipose but no lymph node metastases. His course was uneventful with enrollment in a monoclonal antibody research treatment protocol. Eight years later, he presented with hematuria. A PET/CT demonstrated a hypermetabolic right external iliac lymph node and a hypermetabolic mass within a urachal remnant. The mass was excised and pathologically proven to represent a metastasis from the original primary tumor.     

A huge gastric diverticulum

Summary A case is presented in which a huge gastric diverticulum produced symptoms of epigastric burning and postprandial regurgitation. Surgical resection relieved the patient's symptoms. A review of the literature reveals that this diverticulum is one of the largest reported.The authors would like to acknowledge the medical assistance of Dr. Jack B. Pontz, who first recognized the association between this patient's symptoms and his gastric diverticulum. They would further like to acknowledge gratefully the surgical assistance of Dr. G. Gary Kirchner and the radiographic assistance of Dr. Paul W. Eyler. All the above named are associated with the Lancaster General Hospital.