Exploitation of microbial forensics and nanotechnology for the monitoring of emerging pathogens

Emerging infectious diseases remain among the leading causes of global mortality. Traditional laboratory diagnostic approaches designed to detect and track infectious disease agents provide a framework for surveillance of bio threats. However, surveillance and outbreak investigations using such time-consuming approaches for early detection of pathogens remain the major pitfall. Hence, reasonable real-time surveillance systems to anticipate threats to public health and environment are critical for identifying specific aetiologies and preventing the global spread of infectious disease. The current review discusses the growing need for monitoring and surveillance of pathogens with the same zeal and approach as adopted by microbial forensics laboratories, and further strengthening it by integrating with the innovative nanotechnology for rapid detection of microbial pathogens. Such innovative diagnostics platforms will help to track pathogens from high risk areas and environment by pre-emptive approach that will minimize damages. The various scenarios with the examples are discussed where the high risk associated human pathogens in particular were successfully detected using various nanotechnology approaches with potential future prospects in the field of microbial forensics.     

HIV risk in Karachi and Lahore, Pakistan: an emerging epidemic in injecting and commercial sex networks

The objective of this study was to measure HIV prevalence and risk behaviour in injecting drug users (IDUs), male sex workers (MSWs), Hijras (transgenders), female sex workers (FSWs) and male truckers in Karachi and Lahore, Pakistan. The design was a linked-anonymous cross-sectional study of individuals identified at key venues or through peer referral. Approximately 400 respondents in each group (200 for Hijras) responded to a standardized questionnaire and were tested for HIV antibodies at each site. In Karachi, 23% of IDUs and 4% of MSWs were HIV positive, and HIV-positive individuals were identified in all risk groups in at least one city. Two-thirds of all IDUs used a shared needle in the previous week, and unprotected commercial sex activity with men and women was high. The HIV epidemic has entered IDU and male and female commercial sex networks in Karachi and Lahore. Targeted intervention services must be scaled up and risk group surveillance intensified.     

Simple provocative maneuvers in renal transplant scintigraphy for detecting urine leak

Urine leak in the early postoperative period following renal transplantation is a serious complication requiring early identification and aggressive intervention, which significantly reduces the morbidity and mortality. Renal transplant scintigraphy is a noninvasive method to evaluate the perfusion and function of a transplanted kidney and urinary drainage including urine leak. Here, we reported two cases in which the standard transplant renogram failed to demonstrate urine leak. The cases were referred for a diethylenetriaminepentaacetic acid renogram following the transplantation to evaluate the cause of symptoms or elevated serum creatinine level. In both the cases, urine leak was successfully detected following simple maneuvers such as diuretic administration or Foley catheter irrigation. Renal transplant scintigraphy is an effective and safe technique and the use of these simple maneuvers can enhance the diagnostic sensitivity of the transplant renogram in the detection of urine leak.     

Nonhuman primate models of NeuroAIDS

Human Immunodeficiency virus (HIV), the virus that causes acquired immunodeficiency syndrome (AIDS), also manifests neurological complications. HIV-associated dementia (HAD) is the most severe form of HIV-induced neurocognitive disorders. HIV encephalitis (HIVE), the pathological correlate of HAD, is characterized by the formation of multinucleated giant cells and microglial nodules, astrocytosis, and neuronal damage and loss. Pathological evaluation of HAD disease progression in humans is not possible, with the only data collected being from individuals who have succumbed to the disorder, a snap shot of end-stage disease at best. Therefore, pertinent animal models have been developed to alleviate this gap of knowledge in the field of neurovirology and neuroinflammation. In general, the most widely used animal models are the simian immunodeficiency virus (SIV) and the chimeric simian/human immunodeficiency virus (SHIV) macaque model systems. Although both SIV and SHIV model systems are able to potentiate neuroinvasion and the concomitant neuropathology similar to that seen in the human syndromes, the innate differences between the two in disease pathogenesis and progression make for two separate, yet effective, systems for the study of HIV-associated neuropathology.     

Adult weight gain and central obesity in women with and without a family history of breast cancer: a case control study

Adult weight gain and central obesity can increase breast cancer risk. We determined the prevalence of adult weight gain and central obesity amongst women with a family history (FH) as compared to women with a population risk to determine whether adiposity could contribute to their increased risk. Adult weight gain, waist and waist:hip ratio (WHR) were determined amongst 475 women (aged 20–60 years) attending a regional FH breast cancer risk clinic, compared to 312 age matched women at population risk. Patterns of adult weight gain did not differ between women with and without a FH of breast cancer. The majority of weight gain occurred between the ages of 20 and 40 in both groups. Mean (sd) weight gain for women aged >40 years with a FH was 8.9 (10.3) kg compared to 9.1 (10.6) kg for controls (p = 0.85). Women with a FH had a significantly greater waist and WHR than controls. Mean (sd) waist was 83.7 (13) cm compared to 81.6 (11.3) cm for controls (p < 0.01). Mean (sd) WHR was 0.82 (0.1) compared to 0.80 (0.1) for controls (p < 0.01). FH of breast cancer was an independent predictor of having a WHR of >0.85; odds ratio (95% CI) = 1.42 (1.01–2.01) (p = 0.044). Significant weight gain between the ages of 20 and 40 and the prevalence of central obesity amongst FH women suggest the need for weight management within FH clinics.     

B-type natriuretic peptide levels in patients with COPD and normal right ventricular function

INTRODUCTION: Evidence suggests that elevated plasma levels of B-type natriuretic peptide (BNP) are found in patients with chronic obstructive pulmonary disease (COPD) and right ventricular dysfunction. We examined the effects of exercise on plasma BNP levels in patients with COPD who have normal right ventricular function METHODS: Seventeen patients with a diagnosis of COPD and normal right ventricular function demonstrated by radionuclide ventriculography, and 17 age-and sex-matched healthy subjects underwent a treadmill exercise test. Plasma BNP levels were measured sequentially before, immediately after, and 1 hour after the exercise test RESULTS: The mean plasma BNP+/-standard deviation levels of the COPD and control groups before exercise were 21.3+/-16 pg/ml and 13.4+/-11 pg/ml, respectively (P>0.05). Mean plasma BNP level measured immediately after exercise was 37.9+/-31 pg/ml in the COPD group, reflecting a statistically significant increase when compared with the initial value (P<0.05). The control group did not show any significant change in plasma BNP levels after the exercise test CONCLUSIONS: Exercise induces an increase in plasma BNP levels in patients with COPD who do not have right ventricular dysfunction at rest. Measurement of exercise-induced BNP levels may be a useful alternative to pulmonary artery catheterisation in identifying the patients who are likely to benefit from long-term oxygen therapy.     

Indium-111 octreotide scintigraphy in patients with bone tumours of the extremities

Radiolabelled somatostatin analogues are of potential value in the imaging of somatostatin receptor-positive tumours. Recently, somatostatin receptors have been demonstrated in the osteoblast precursor cells. In this preliminary study, we evaluated the uptake characteristics of indium-111 octreotide in two benign and two malignant bone tumours. Tracer accumulation was observed in all four cases, and overall lesion to background ratio (mean±SD) was 2.74±0.84 and 2.98±1.49 at 4 h and 24 h, respectively. There was no clear relationship between I¹¹¹In-octreotide accumulation and the benign or malignant nature of the tumour. In one patient, tracer uptake was inhibited by unlabelled octreotide administration. These results suggest that¹¹¹In-octreotide can be taken up by benign and malignant bone tumours. The inhibition of tumour uptake by treatment with cold octreotide supports the concept that specific uptake mechanisms are responsible for¹¹¹In-octreotide deposition by bone tumours.     

In situ localization of transforming growth factor beta and S-phase cells in patients with acute myeloid leukemia and myelodysplastic syndrome.

In situ localization of transforming growth factor beta (TGF-B) was accomplished in 16 acute myeloid leukemia (AML) and 11 myelodysplastic syndrome (MDS) cases. A modified and greatly shortened procedure for immunohistochemical localization of TGF-B using a monoclonal antibody was undertaken in plastic embedded bone marrow biopsy sections that demonstrated excellent preservation of morphologic detail. In addition, a double-label procedure was developed for the simultaneous detection of TGF-B and cells actively engaged in DNA-synthesis which were labeled in vivo by infusing thymidine analogues. Marked variation in intensity of TGF-B staining in interstitial areas of biopsies was noted among different patients. TGF-B was also conspicuously present in the basement membrane of blood vessel endothelial cells and the cytoplasm of megakaryocytes. Double-labeling revealed that S-phase cells in a number of MDS cases appeared clustered together and that megakaryocytes in S-phase were completely devoid of TGF-B.