Asymptomatic neonatal herpes simplex virus infection in mice leads to long-term cognitive impairment.

Neonatal herpes simplex virus (nHSV) is a devastating infection impacting approximately 14,000 newborns globally each year. Infection is associated with high neurologic morbidity and mortality, making early intervention and treatment critical. Clinical outcomes of symptomatic nHSV infections are well-studied, but little is known about the frequency of, or outcomes following, sub-clinical or asymptomatic nHSV. Given the ubiquitous nature of HSV infection and frequency of asymptomatic shedding in adults, subclinical infections are underreported, yet could contribute to long-term neurological damage. To assess potential neurological morbidity associated with subclinical nHSV infection, we developed a low-dose (100 PFU) HSV infection protocol in neonatal C57BL/6 mice. At this dose, HSV DNA was detected in the brain by PCR but was not associated with acute clinical symptoms. However, months after initial inoculation with 100 PFU of HSV, we observed impaired mouse performance on a range of cognitive and memory performance tasks. Memory impairment was induced by infection with either HSV-1 or HSV-2 wild-type viruses, but not by a viral mutant lacking the autophagy-modulating Beclin-binding domain of the neurovirulence gene γ34.5. Retroviral expression of wild type γ34.5 gene led to behavioral pathology in mice, suggesting that γ34.5 expression may be sufficient to cause cognitive impairment. Maternal immunization and HSV-specific antibody treatment prevented offspring from developing neurological sequelae following nHSV-1 infection. Altogether, these results support the idea that subclinical neonatal infections may lead to cognitive decline in adulthood, with possible profound implications for research on human neurodegenerative disorders such as Alzheimer's Disease.

Use of atropine in patients with recent myocardial infarction during exercise myocardial perfusion study. Use of atropine during exercise myocardial perfusion SPECT.

BACKGROUND: Patients with recent myocardial infarction frequently require a myocardial perfusion study for risk stratification. However a conclusive study cannot be accomplished in many due to non-attainment of target heart rate. AIM OF THE STUDY: To evaluate the effect of pre-stress administration of atropine in exercise performance of patients with recent myocardial infarction. MATERIAL AND METHODS: Study included 43 test and 43 control patients and were matched for their age, sex, status of pretest exercise tolerance, area of infarction and for interval between infarction and stress thallium test. Atropine (0.01 mg/kg) was administered intravenously 3 min prior to treadmill stress in all the 43 test patients and no atropine was administered to control patients. RESULTS: Target heart rate was attained in 95.3% patients receiving atropine compared to in 67.4% of control patients. There was no significant difference between mean ages (p>0.33), basal BP (p>0.47), peak BP (p>0.18) of both groups. There was significant difference between the increment in exercise-induced heart rate (p<0.004), peak heart rate (p<0.001) and double product (p<0.001) attained between both groups. No significant adverse effect was noted in patients who received atropine. CONCLUSION: Pre-stress administration of atropine in patients with recent myocardial infarction is safe and results in a significantly better exercise performance, which might be useful in decreasing the number of equivocal myocardial perfusion studies.

Do healthy potential kidney donors in india have an average glomerular filtration rate of 81.4 ml/min?

BACKGROUND: Until now, a normal reference range for glomerular filtration rate (GFR) in adult Indian potential kidney donors has not been determined and values from a western population are being used as reference. AIM: To determine the reference range of GFR in healthy adult Indian potential kidney donors. BASIC PROCEDURES: GFR was measured in 610 (250 male, 360 female, average age 35.16 years) healthy potential kidney donors using the 99mTc-DTPA (diethylenetriamine pentaacetic acid) two-plasma sample method of Russell. RESULTS: The mean body surface area (BSA)-normalized GFR value of a young healthy Indian adult potential kidney donor was calculated as 81.4 +/- 19.4 ml/min/1.73 m2 BSA--for males it was 82.3 +/- 21.3 ml/min/1.73 m2 BSA and for females 80.8 +/- 18.1 ml/min/1.73 m2 BSA. There was no significant difference between derived mean GFR values in males and females with a p value of 0.37. CONCLUSIONS: The normal GFR value for the healthy Indian adult potential kidney donor appears to be much lower than the accepted value for a western population. The mean GFR value of a young healthy Indian adult potential kidney donor is 81.4 +/- 19.4 ml/min/1.73 m2 BSA, which is significantly different from the normal value of 109-125 ml/min derived from a western population. These findings might be useful in deciding on a suitable kidney donor in an Indian context.

Role of skeletal scintigraphy in soft tissue sarcoma: Improving the diagnostic yield.

BACKGROUND: The presence of skeletal metastases significantly influences the therapeutic strategy adopted for soft tissue sarcoma. However, literature on the prevalence of skeletal metastases in soft tissue sarcoma is limited and none of the available data is based on the Indian patient population. AIM: To determine the prevalence of skeletal metastases at presentation in patients of soft tissue sarcoma and to rationalise the use of preoperative skeletal scintigraphy in such patients. METHODS AND MATERIAL: Preoperative bone scans were evaluated in 122 patients with soft tissue sarcoma (median age, 34 years; range, 4-83). The scans were classified into 3 grades: Grade 1: metastases very likely; Grade 2: equivocal; Grade 3: normal or benign lesion. In all the patients studied, the ability of the patient to localize the site or sites of pain was recorded and that was correlated with the site of metastases in scintigraphy. RESULT: Seventeen (13.9%) patients had Grade 1 scan; 16 of them had bony pain that was not readily explainable by trauma or other local factors. Ten ( 8.1%) patients had Grade 2 scan, five of them had bony pain which was not readily explainable by trauma or other local factors. Ninety-five patients (77.8%) had Grade 3 scan. Of these, 9 had localised bone pain which could be definitely associated with trauma or joint degeneration. CONCLUSION: The prevalence of skeletal metastases at presentation in patients with soft tissue sarcoma is low (13.9%). The low rates of skeletal metastases in bone pain-free patients (0.9%) versus the high rate in symptomatic patients (76.1%) supports the use of bone scanning in symptomatic patients only.

Prevalence of vesicoureteral reflux in patients with incidentally diagnosed adult hypertension.

OBJECTIVES: To evaluate the prevalence of vesicoureteral reflux (VUR) in hypertensive patients without any other evidence of renal involvement. Reflux nephropathy may be clinically latent and present in early adulthood as hypertension when superimposed confounding factors are added. METHODS: The medical records of 157 adult hypertensive patients with normal renal parameters and low-probability, captopril-enhanced renal dynamic scan findings who underwent direct radionuclide voiding cystoscintigraphy between June 1998 and May 2003 were retrospectively analyzed. RESULTS: VUR was documented in 30 patients (19.1%). In those 30 patients, VUR was mild in 8 (26.6%), moderate in 6 (20%), and severe in 16 (53.3%) patients. Bilateral VUR was seen in 7 patients, graded as severe in all cases. The prevalence by age was 20% in the 18 to 30-year-old group, 16.6% in the 31 to 45-year-old group, and 20% in the older than 45-year-old group. CONCLUSIONS: The results of this study have shown that VUR is present in a significantly large proportion of adult patients with hypertension without any apparent renal parenchymal or renovascular involvement.

Detection of coronary artery disease by stress thallium scintigraphy in diabetic patients.

We investigated the efficacy of exercise stress thallium in the diagnosis of coronary artery disease in patients with diabetes mellitus. Forty-three patients with known diabetes and suspected of having coronary artery disease were included in the study. All the patients underwent coronary angiography, 24 had significant coronary artery stenosis and 19 had normal coronaries. Out of the 24 patients with a positive angiographic finding, thallium scintigraphy was positive in 21 patients (sensitivity, 87.5%); and false negative in only three of the 24 patients. Out of the 19 patients with normal angiography findings, 16 patients had a normal thallium scan (specificity, 84.2%) and the remaining three had a positive thallium scan. This gives thallium scintigraphy a positive predictive value of 87.5% and negative predictive value of 84.2% when compared with coronary angiography. The findings of this study suggest that stress thallium scintigraphy is a useful modality in screening of coronary artery disease in diabetic patients.