Implications of aging and the endoplasmic reticulum unfolded protein response on the molecular modality of breast cancer

The endoplasmic reticulum (ER) is an important subcellular organelle that is involved in numerous activities required to achieve and maintain functional proteins in addition to its role in the biosynthesis of lipids and as a repository of intracellular Ca²⁺. The inability of the ER to cope with protein folding beyond its capacity causes disturbances that evoke ER stress. Cells possess molecular mechanisms aimed at clearing unwanted cargo from the ER lumen as an adaptive response, but failing to do so navigates the system towards cell death. This systemic approach is called the unfolded protein response. Aging insults cells through various perturbations in homeostasis that involve curtailing ER function by mitigating the expression of its resident chaperones and enzymes. Here the unfolded protein response (UPR) cannot protect the cell due to the weakening of its protective arm, which exacerbates imbalanced homeostasis. Aging predisposed breast malignancy activates the UPR, but tumor cells maneuver the mechanistic details of the UPR, favoring tumorigenesis and thereby eliciting a treacherous condition. Tumor cells exploit UPR pathways via crosstalk involving various signaling cascades that usher tumor cells to immortality. This review aims to present a collection of data that can delineate the missing links of molecular signatures between aging and breast cancer.

Extended spectrum β--lactamases in Escherichia coli & Klebsiella pneumoniae & associated risk factors.

Background & objectives: Extended spectrum β-lactamases (ESBLs) have emerged as a major threat worldwide with limited treatment options. The genotypes of ESBL producing strains largely remain unknown in India; hence the present study was aimed to determine the occurrence of ESBLs in Escherichia coli and Klebsiella pneumoniae, their molecular types and associated risk factors in a tertiary care hospital. Methods: Total 200 consecutive clinical isolates of E. coli (n=143) and K. pneumoniae (n=57) collected between February and July 2006 at Sanjay Gandhi Postgraduate Institute of Medical Sciences, a tertiary care hospital in north India, were examined phenotypically for ESBL production. ESBL strains were further typed for the blaTEM/SHV/CTX-M genes by PCR using specifi c primers. The blaCTX-M cluster was identifi ed by restriction analysis and genotype by sequencing of PCR product. Resistance to other antimicrobial agents was also studied. Various risk factors associated with ESBL infections were analyzed by logistic regressions. Results: ESBLs were found in 63.6 per cent E. coli and 66.7 per cent K. pneumoniae isolates. Majority of the typeable isolates harboured two or more ESBL genes (57.3%). Overall blaCTX-M was the commonest genotype (85.4%) followed by blaTEM (54.9%) and blaSHV (32.9%) either alone or in combination. All CTX-M enzymes in E. coli and 87.5 per cent in K. pneumoniae belonged to the CTX-M-1 cluster. Sequencing was done for randomly selected 20 blaCTX-M PCR products and all were identifi ed as CTXM- 3. Resistance of ESBL isolates to other antibiotics was amikacin 14.7 per cent, gentamicin 66.7 per cent, trimethoprim/sulphamethoxazole 79.1 per cent and ciprofl oxacin 93.8 per cent. Prior antibiotic exposure, use of intravenous device and urinary catheter, renal insuffi ciency and ICU admission were associated with ESBL infection on univariate analysis. On multivariate, antibiotic exposure (P=0.001) and use of urinary catheter (P<0.001) were identififi ed as risk for ESBL infection. Interpretation & conclusions: Our study showed high ESBL occurrence with CTX-M as the emerging type in our hospital and CTX-M-3 being reported for the fi rst time in India. High co-resistance to other non-β-lactam antibiotics is a major challenge for management of ESBL infections.

Emerging vancomycin resistance in enterococci in India.

Infection caused by vancomycin resistant enterococci (VRE) leads to adverse outcome and is a real challenge. Despite increasing reports of VRE in different countries, there is scanty data on this issue from India. A total of 685 enterococci were isolated from various clinical samples from January to December 2004. Antimicrobial susceptibility was performed as prescribed by National Committee for Clinical Laboratory Standards (NCCLS). Vancomycin resistance was confirmed by minimum inhibitory concentration (MIC). Resistant phenotype was determined by Polymerase chain reaction (PCR). Of 685, 456 (67%) were E. faecalis and 229 (33%) were E. faecium. Resistance to various antibiotics in E. faecalis and E. faecium was as follows: ampicillin 33% and 54%, erythromycin 91% and 86%, ciprofloxacin 69% and 81%, tetracycline 50% and 54% and high level gentamicin resistance in 62% and 77% respectively. Vancomycin resistance was confirmed in 10 (1.4%) cases by MIC and all had Van A phenotype by PCR. Emergence of vancomycin resistant enterococci is of great concern because of its epidemic potential and scanty therapeutic options. Prompt diagnosis and efficient infection control measures can restrict its spread.

Helicobacter pylori-induced apoptosis in pathogenesis of gastric carcinoma.

BACKGROUND: Despite a possible role of Helicobacter pylori in gastric carcinoma (GC), its pathogenesis is not clear. There is scanty data on apoptosis in GC in relation to H. pylori and CagA antibody. Therefore, we studied gastric epithelial apoptosis in GC and non-ulcer dyspepsia (NUD) with or without H. pylori infection, and the degree of apoptosis in relation to CagA antibody status. METHODS: 20 patients each with GC and NUD were investigated for H. pylori using rapid urease test (RUT), IgG anti-H. pylori and anti-CagA antibodies, histology of endoscopically normal-looking mucosa for H. pylori, intestinal metaplasia (IM), and apoptosis using TUNEL assay. Positivity to one tissue-based (RUT or histology) and one serology based (anti-H. pylori or CagA IgG) test was taken as diagnostic of active H. pylori infection, and negative result in both tissue-based tests suggested its absence. RESULTS: Patients with GC more often had anti-H. pylori IgG (16 of 20 vs. 8 of 20; p=0.02) and a trend towards higher apoptotic index (AI) (48.6 [19.2 to 71.7] vs. 41.4 [11.7 to 63.6]; p=0.06) than NUD. AI was higher in GC (66.7 [57.5 to 71.7] vs. 32.6 [19.2 to 39.8]; p<0.0001) and NUD (58.6 [50.7 to 63.6] vs. 24.4 [11.7 to 32.2]; p<0.0001) infected with H. pylori than in those without infection. AI was also higher in GC than in NUD with H. pylori infection (66.7 [57.5 to 71.7] vs. 58.6 [50.7 to 63.6]; p=0.01). Four of the 20 patients with GC and none with NUD had IM (p=ns). There was no difference in AI in relation to CagA antibody. AI positively correlated with patients' age in presence of H. pylori infection (correlation coefficient=0.5, p=0.03) but not in its absence. CONCLUSION: Exaggerated apoptosis may play a role in H. pylori-mediated gastric diseases including carcinogenesis. AI increases with aging in patients infected with H. pylori.

Nocardial brain abscesses in a HIV positive patient misinterpreted as tubercular brain abscesses.

We present a case of nocardial (Nocarda transvalensis) brain abscesses in a HIV infected person with CD4 count of 53 cells/ml, who received antitubercular therapy for one year. A magnetic resonance imaging study showed multiple ring-enhancing lesions in right parieto-occipital parenchymal region along with perilesional edema and mass effect. Right posterior temporal burr hole aspiration of the abscesses and postoperative cotrimoxazole and ampicillin-sulbactum therapy cured the patient. It is a case of HIV infection with rare and sole manifestation of multiple cerebral abscesses due to N. transvalensis.

Sero-molecular evaluation of human cytomegalovirus disease in renal transplant rejection.

Cytomegalovirus (CMV) is the most common viral pathogen in renal transplant recipients resulting in graft rejection. The prevalence of CMV disease and renal graft rejection is not well studied in India. Sequential specimens from 32 renal allograft recipients were examined by using CMV IgM specific mu capture ELISA and DNA by PCR. Twelve of the 32 patients were CMV IgM positive and out of 12 patients, 9 had rejection and 4 experienced CMV disease. CMV IgM specific mu capture ELISA helped in diagnosis of CMV disease, though it is less sensitive in detection of rejection. PCR itself was proved not sensitive enough in detecting either CMV disease or rejection. At present, optimal laboratory detection of CMV infection in these patients can be achieved only by multiple and more sensitive parameters.

Frequency of leptospirosis in patients of acute febrile illness in Uttar Pradesh.

OBJECTIVE: This study was performed to asses the disease burden of leptospirosis in and around Lucknow among patients presenting with acute febrile illness and conforming to the case definition of leptospirosis. METHODS: A total of 346 serum samples (mostly paired) and an equal number of urine samples were collected from patients presenting with acute febrile illness and fulfilling the criteria of clinical diagnosis of leptospirosis from January 2001 to December 2001. Patients attending a tertiary care hospital as well as from various communities in and around Lucknow were included in this study. All sera and urine samples were tested for the presence of IgM antibody by Leptodipstick test and by dark-field microscopy (DFM) respectively. All positive and 10% negative sera were tested at national leptospirosis reference centre at Andaman and Nicobar Islands for microagglutination test (MAT). RESULTS: IgM antibody was detected in 25/346 (7%) patients ranging in age from 9-65 years. DFM was positive in only in one case. MAT was positive in 4/17 cases tested and the prevalent serogroups were L. grippotyphosa and L. pomona in two each. Common presenting features in these patients were fever (25/25) and jaundice (17/25). History of contact with animal or water contaminated with animal urine was present in 96% cases. CONCLUSION: Leptospirosis is not uncommon in Uttar Pradesh. However larger epidemiological studies are required to know the actual disease burden. Dark-field microscopy is an insensitive method for the diagnosis of leptospirosis and is not suitable for surveillance.

Multisystem involvement of microfilaria in a HIV positive patient.

A 35-year-old HIV positive male presented with dyspnoea and chest pain was diagnosed having acute pericardial and pleural effusion. Microfilaria was detected from blood as well as from the pericardial and pleural fluid and from urine. CD4 count was 123 cells microl. The patient was receiving treatment with antiretroviral therapy and Cotrimoxazole for last 4 months. The patient had no opportunistic infection and no symptoms suggestive of filarial infection in the past. This is for the first time we are reporting high microfilarial load (1000/ml) from blood in HIV positive patient, where microfilaria was also demonstrated from the pericardial and pleural fluid and from urine.

Neurocysticercosis in clinically suspected and MRI proven cases: evidence of sub-optimal antibody response.

Neurocysticercosis (NCC) has a worldwide distribution mainly in the developing countries like India. The study was done to find the seroprevalence of anti-cysticercus antibodies in clinically suspected and MRI proven cases and to corroborate the serological findings with radiological findings (MRI). A hospital based study among 204 suspected patients during January, 1996 to August, 2001 showed that 77 (32.2%, M:F = 2.2:1) had serological evidence of NCC. Of the total 189 sera, tested at 1:100 dilution 68 (35.9%) and of the total 50 CSF, tested at 1:5 dilution 9 (18%) were positive for anti-cysticercus IgG antibodies. In 35 cases where both were tested 13 sera (37.1%), 9 CSF (25.7%) and in 7 (20%) both sera and CSF were positive. In CSF from 62 patients with tubercular meningitis (disease control) 2 (3.2%) samples whereas in sera of 60 normal blood donors (normal control) 7 (11.7%) samples had anti-cysticercus IgG antibodies. In 33 MRI-positive cases, anti-cysticercus antibodies were seen in 15 (45.4%) patients. Antibodies were seen in 6 of 14 (42.8%) cases with single cortical cyst, 4 of 11 (36.3%) with 2-3 cysts and in 5 of 8 (62.5%) with multiple cysts. Alternatively, 18 of 33 (54.5%) MRI positive cases lacked anti-cysticercus antibodies. Six MRI negative cases were found to be seropositive and were treated successfully. Hence, immune response was sub-optimal even in MRI positive cases and conversely, few MRI negative cases were seropositive. Since positive response with MRI or serology depends on the stage of the disease, therefore both tests should be done together to confirm or to rule out NCC.

Role of mechanical ventilation & development of multidrug resistant organisms in hospital acquired pneumonia.

BACKGROUND & OBJECTIVES: Among hospital-acquired infections, pneumonia is considered to be the leading cause of death mainly in patients with mechanical ventilation in intensive care units (ICUs). The present study was undertaken to estimate the occurrence of hospital-acquired pneumonia (HAP) as well as ventilator-associated pneumonia (VAP) along with the effect of different variables and to detect the presence of multi drug resistant (MDR) organisms in the intensive care unit (ICU). METHODS: Of the 328 patients admitted in the ICU during 2001, 241 stayed for > 72 h and 148 were ventilated. The respiratory specimens collected from the cases and controls were sent for cytology, bacterial culture and antimicrobial sensitivity. RESULTS: The overall rate of HAP was 53.9 per cent, mortality rate was 47.3 per cent and attributable risk of mortality with ventilator was 72.3 per cent. Occurrence of VAP was 81.7 per cent. The rate of acquisition of HAP increased along with the duration of stay in the ICU. Of the total bacterial isolates, 96.2 per cent were obtained from patients on ventilator, an overall preponderance of Gram-negative bacteria, commonest being Pseudomonas spp along with 16.3 per cent polymicrobial infection was found in ICU. A significant number of ICU isolates were MDR in comparison to those from the non-ICU settings. INTERPRETATION & CONCLUSION: Mechanical ventilation and duration of ICU stay emerged as important risk factors for the development of HAP and VAP. MDR Gram-negative bacilli were the commonest respiratory pathogens responsible for increased mortality in patients with VAP.

Seroanalysis of Chlamydia trachomatis and S-TORCH agents in women with recurrent spontaneous abortions.

Genital tract infections are an important cause of pregnancy loss, many of which are amenable to treatment. There is scarcity of literature on role of S-TORCH agents in recurrent spontaneous abortions (RSA) and available data on role of Chlamydia trachomatis (CT) is controversial. In a retrospective analysis, CT IgM, IgG and IgA antibodies were tested by indirect ELISA in 86, 53 and 30 sera samples respectively from women with RSA (= or > 3 abortions). IgM antibodies using m-capture ELISA for S-TORCH agents (Syphilis, tested by VDRL) were analysed in 47 sera from women with RSA. Results compared with 29 age matched normal pregnant women. Anatomical, endocrine, Rh incompatibility and chromosomal abnormality in the couple were ruled out prior to inclusion in the study. Serum anti-CT IgM positivity was 46.5% in RSA vs. 13.8% in control group (p < 0.001). S-TORCH positivity in RSA group was 31.9% and nil in the control group (p < 0.005). Present study demonstrates a strong association between IgM antibodies to CT and S-TORCH agents in women with history of RSA.

Serodiagnosis of smear and culture-negative neurotuberculosis with enzyme linked immunosorbent assay for anti A-60 immunoglobulins.

Early diagnosis of neurotuberculosis (NTB), useful in prevention of mortality and morbidity, remains a challenge despite availability of several tests. An ELISA test to detect IgG and IgM antibodies against Mycobacterial antigen A-60 (Anda Biologicals, France) was done in 677 specimens; group 1 (NTB): 373 sera and 167 cerebrospinal fluid (CSF), group 2: 100 sera from healthy subjects, group 3: 17 CSF from patients undergoing neurosurgical operations for non-tubercular diseases. Anti-A 60 IgA estimation was done in 99 sera from group 1 and all 100 from group 2. Working dilutions were 1:200 for serum and 1:10 for CSF. Serum IgM and IgG anti-A 60 antibodies were more often detected in group 1 than in 2 (50% Vs 10%, p<.001). Anti-IgG and IgM antibody were detected more often in group 1 than in group 3 (33% Vs 6%, p<.001). In serum and CSF both IgM positivity was more than IgG in 2 subgroups of NTB and these are tubercular meningitis, spinal tuberculosis whereas in tuberculoma IgG positivity was more as compared to other 2 groups. Sera were more often positive than CSF (50% Vs 33%, p<.001). Of 32 patients, in whom magnetic resonance imaging (MRI) was done, 15/18 (83%) patients with suggestive findings in MRI had a positive ELISA (IgG or IgM). AntiA-60 antibody is a useful aid in the diagnosis of NTB, especially in smear and culture negative NTB where one does not have much diagnostic opportunities to choose from.