Utility of a real-time fluorescence imaging device in guiding antibiotic treatment in superficial skin infections.

The prescription of antibiotics empirically without confirmation of an infective etiology is on the rise. Administration of appropriate antibiotics can be guided by real-time fluorescence imaging using a point-of-care device. These composite images show the presence, type and the burden of infection. The time saved by this method over microbiological testing, especially in resource-poor settings, can lead to a paradigm shift in treatment by facilitating prompt and adequate antimicrobial therapy, surgical debridement as well as follow-up. Thumbnail sketches of a series of four cases highlighting different scenarios in which a fluorescent imaging device utilizing artificial intelligence and machine learning was found useful is presented in this report.

Prevalence of Human T Cell Leukaemia Virus amongst Blood Donors.

BACKGROUND: Human T cell leukaemia virus (HTLV) I/II are retroviruses implicated in transfusion transmitted infection. Present study was undertaken to assess seroprevalence of HTLV in voluntary blood donors along with pattern of blood utilisation. METHODS: A total of 258 healthy blood donors who were free from infectious markers in transfusion as per current transfusion guidelines were enrolled. They were screened for HTLV-I/II antibodies by commercially available enzyme immuno assay (EIA) and their blood utilisation data was analysed. RESULT: Five (1.9%) donors were found seropositive for HTLV-I/II of which 1.2 % were first time and 0.9% were repeat donors. Blood utilisation data revealed 20.9% and 38.8% units were utilised within 5 and 6-14 days of collection respectively. 45.9% recipients were transfused with single blood unit. 42.9% recipients were immunosuppressed due to underlying disease. CONCLUSION: The high prevalence of HTLV in blood donors, coupled with single unit transfusion, use of fresh blood, non availability of acellular blood products and immunosuppression in recipients can lead to significant transfusion transmitted HTLV infection. We suggest judicious use of blood products and screening of blood donors in prevention of transfusion transmitted HTLV-I/II.

Hepatitis B Immunisation in Health Care Workers.

BACKGROUND: Hepatitis B virus (HBV) infection is an important occupational risk in health care workers (HCW). In spite of HBV vaccine availability in Armed Forces, the high prevalence of HBV infection in HCW continues to be a problem. The study was undertaken to study the HBV vaccine-compliance among HCW. METHODS: A cross-sectional study was conducted at a tertiary care hospital. HCW were requested to fill up the pre set questionnaire to assess the HBV vaccination coverage. RESULT: Amongst 254 HCW, only 57.7% were vaccinated against HBV. The vaccine compliance was lowest among housekeeping professionals. The mean age at vaccination was high (30.5 years). Amongst the vaccine non-compliant subjects, 34.3% were above 30 years of age. 32.2% HCW completed primary vaccination after spending more than 10 years in the profession. Accessibility of HBV vaccine, knowledge and perception of HBV risk were important factors in vaccine non-compliance. CONCLUSION: Due to low and delayed HBV vaccine-compliance, HCW continue to be at the risk of occupational HBV. Health education highlighting occupational risk of HBV, accessibility of vaccine and mandatory vaccination of HCW is recommended to increase HBV vaccine compliance among HCW.

Coexistence of ß-Lactamases in Community-Acquired Infections in a Tertiary Care Hospital in India.

INTRODUCTION: The trends of ß-lactamases producing Enterobacteriaceae is ever increasing, and limited studies have reported investigating coexistence of ß lactamases in Enterobacteriaceae. A cross-sectional study after approval from the Institutional Ethical committee was conducted between June 2014 and May 2016 in community-acquired infections due to multidrug-resistant organisms in our tertiary care. Nonrepetitive clinical samples from the out-patient department (OPD) were processed for bacteriological culture and identification of Enterobacteriaceae. An antibiotic susceptibility test, screening, and phenotypic confirmation for ESBLs and carbapenemases and AmpC producers were performed to check for coexistence of these enzymes. RESULTS: Nonrepetitive clinical specimens processed for culture and identification in our hospital revealed 417 positive isolates in community acquired infections which were multidrug-resistant organisms, and on screening for ß-lactamases, 293 isolates were positive for one of the three beta lactamases, ESBL, AmpC, or carbapnemases. Coproduction of ESBL and MBL was seen in 5 isolates, 35 isolates showed coproduction of ESBL and AmpC enzymes, and AmpC and MBL coproduction was exhibited in only in 5 isolates. CONCLUSIONS: Coexistence of ESBLs, AmpC producers, and carbapenemases has been described. Continuous monitoring and surveillance and proper infection control and prevention practices will limit the further spread of these superbugs within the hospital and beyond.

Antibody to Hepatitis B Surface Antigen in Vaccinated Health Care Workers.

BACKGROUND: Health care workers (HCWs) in Armed Forces are immunised against Hepatitis B virus (HBV), however they are not subjected to anti-HBs (antibody to Hepatitis B surface antigen) assessment after primary vaccination. The present study was undertaken to determine the protection offered by HBV vaccine in HCW. METHODS: Cross-sectional study was carried out at tertiary care hospital. A total 146 HBV vaccine compliant HCW were evaluated for quantitative anti-HBs by enzyme immune assay. RESULT: 129 (88.4%) subjects had protective levels of anti-HBs. Higher age at vaccination was an important risk factor in low vaccine response. Decline in anti-HBs with time was evident. Anti-HBs levels were more than 10mIU/ml in subjects even after 11 years of primary vaccination. There was no difference in protection in booster and non booster groups. CONCLUSION: Age is the most important factor in HBV vaccine response. Booster dose of HBV vaccine is not necessary in healthy HCW for atleast ten years after primary vaccination. The study recommends early primary vaccination of HCW and 'initial' anti-HBs assay for confirmation of vaccine response.

Immunochromatographic Methods in Malaria Diagnosis.

BACKGROUND: Malaria remains a major cause of morbidity and mortality in India. This study was carried out to evaluate the use of parasite lactate dehydrogenase (pLDH) test in diagnosis of malaria. METHODS: Blood slides of 400 patients who presented with fever including 104 patients with clinical features suggestive of malaria were studied. The results were compared with microscopy and another immunochromatography test (ICT) based on detection of histidine rich protein-2 antigen [Pfhrp-2] secreted by Plasmodium falciparum. RESULT: In this study the sensitivity and specificity for detection of Plasmodium vivax was 100% while for Plasmodium falciparum the values were 96% and 100% respectively. CONCLUSION: ICT is useful for diagnosis of malaria caused by Plasmodium falciparum in field but microscopy of a well-prepared blood smear must not be omitted in a laboratory setting.

Helicobacter pylori in Dyspepsia - Antibiotic Sensitivity and Virulence Patterns.

BACKGROUND: Helicobacter pylori is implicated in acute superficial gastritis, chronic atrophic gastritis, gastric carcinoma and MALT associated lymphoma. Though colonization can occur in normal individuals, treatment is given if the organism is associated with virulence factors like vacuolating toxin and cytopathic toxin as coded by vacA and cagA genes respectively. No causal relationship between non-ulcer dyspepsia (NUD) and H pylori has been established. This study was carried out to delineate colonizers from pathogens so that appropriate treatment can be planned. METHOD: 100 patients were recruited, 62 with NUD and 38 age and sex matched controls. 4 gastric biopsies and a serum samples were taken from each patient. The biopsies were examined for H pylori by culture, histopathology, rapid urease test, PCR and serum for IgG, IgM and IgA. RESULTS: Culture showed 22.6% positivity and urease 19% among the test group. Histopathology showed 53.2% superficial gastritis and 30.6% chronic gastritis among the test group (P<0.001), PCR for H pylori was positive in 48.3% and vacA and cagA were 29% and 22.6% respectively (P=0.001) among the tests. IgG, IgM and IgA were 41.9%, 46.8% and 43.5% respectively. CONCLUSION: The culture and rapid urease tests were highly specific with high positive predictive value but if negative, infection cannot be ruled out. Similarly IgA and IgM positivity has high positive predictive value for on-going infection where as IgG may be positive in old healed infections also. PCR assay in biopsy specimens is a valuable technique for detection of H pylori with high specificity and sensitivity. The presence of vacA and cagA genes can differentiate innocuous bystanders and potentially invasive organisms.

Outbreak of Multi-drug Resistant Salmonella Typhi Enteric Fever in Mumbai Garrison.

BACKGROUND: There was an epidemic of enteric fever in Mumbai garrison during Nov-Dec 2000 with more than 150 cases admitted to a tertiary care service hospital. METHODS: All the cases presented with fever and some had splenomegaly, bradycardia, abdominal pain and diarrhoea. The epidemic was investigated by the station health organization (SHO) and the case and bacteriological study was carried out in pathology laboratory of the service hospital. The serological study was carried out at Armed Forces Medical College (AFMC), Pune and the Phage typing was carried out at Lady Harding Medical College, New Delhi. RESULTS: Blood cultures were positive in 92(63%) for Salmonella typhi and Widal test was positive in 83(55%). All strains were resistant to four primary drugs i.e. ampicillin, chloramphenicol, co-trimoxazole and tetracycline. All but two were treated successfully with ceftriaxone. The Salmonella typhi belonged to phage group E1 and biotype I. CONCLUSION: Extensive epidemiological investigation of cases and water sources of cantonment area pointed to a common source of the epidemic i.e. the well near 'Gurudwara'.

Interphenylene 7-oxabicyclo[2.2.1]heptane thromboxane A2 antagonists. Semicarbazone omega-chains.

A series of chiral interphenylene 7-oxabicyclo[2.2.1]heptane semicarbazones 19-26 were prepared and evaluated for their in vitro thromboxane (TxA2) antagonistic activity and in vivo duration of action. The potency of 19-26 was found to highly dependent on the substitution pattern of the interphenylene ring and decreased in the order ortho greater than meta much greater than para. SQ 35,091 (25), [1S-(1 alpha,2 alpha,3 alpha,4 alpha)]-2-[[3-[[[(phenylamino) carbonyl]hydrazono]methyl]-7-oxabicyclo[2.2.1]hept-2-yl]methyl] benzenepropanoic acid, was identified as a potent and long-acting TxA2 antagonist. In human platelet rich plasma SQ 35,091 inhibited arachidonic acid (800 microM) and U-46,619 (10 microM) induced aggregation with I50 values of 3 and 12 nM, respectively. In contrast, no inhibition of ADP (20 microM) induced aggregation was observed at greater than 1000 microM. Receptor binding studies with [3H]-SQ 29,548 showed SQ 35,091 was a competitive antagonist with a Kd value of 1.0 +/- 0.1 nM in human platelet membranes. In vivo SQ 35,091 (0.2 mg/kg po) showed extended protection (T50 = 16 h) from U-46,619 (2 mg/kg iv) induced death in mice. These compounds have for the first time demonstrated that a metabolically stable interphenylene alpha-sidechain can be introduced into a prostanoid-like series of TxA2 antagonists with the maintainance of potent antagonistic activity.

Interphenylene 7-oxabicyclo[2.2.1]heptane oxazoles. Highly potent, selective, and long-acting thromboxane A2 receptor antagonists.

A series of interphenylene 7-oxabicyclo[2.2.1]heptane oxazoles (2) were prepared and evaluated for their thromboxane (TxA2) antagonistic activity in vitro and duration of action in vivo. Examination of the carboxyl side chain indicated that the interphenylene ring substitution pattern and, to a lesser extent, chain length were important factors in determining TxA2 antagonistic potency. For the carboxyl side chain, ortho substitution, a single methylene spacer between the interphenylene and oxabicycloheptane rings, and a propionic acid side-chain length were determined to be optimal. With respect to the oxazole side chain a wide range of amide substituents with diverse structures and lipophilicities were compatible with potent antagonistic activity. Finally, an acidic functional group on the alpha-chain and a hydrogen bond acceptor on the 4-position of the oxazole ring were critical for potent activity. From the analogs prepared 42 (BMS-180,291: [(+)-1S-(1 alpha, 2 alpha, 3 alpha, 4 alpha)-2-[[3-[4-[(n- pentylamino)carbonyl]-2-oxazolyl]-7-oxabicyclo[2.2.1]hept-2- yl]methyl]benzenepropanoic acid) was found to be a potent, selective, and orally-active TxA2 antagonist with a long duration of action and has been selected as a candidate for clinical development. In human platelet-rich plasma, 42 inhibited arachidonic acid (800 microM) and U-46,-619 (10 microM) induced aggregation with I50 values of 7 and 21 nM, respectively. Radioligand binding studies of 42 with [3H]-SQ 29,548 showed a Kd value of 4.0 +/- 1.0 nM in human platelet membranes. Both in vitro and in vivo studies indicated 42 was devoid of direct agonistic activity. In vivo 42 (0.2 mg/kg, po) showed extended protection (T50 = 14.4 h) from U-46,619 (2 mg/kg, iv) induced death in mice, and a single oral dose of 42 (3 mg/kg) abolished U46,619-induced platelet aggregation ex vivo in African green monkeys for > 24 h.

Cardioselective antiischemic ATP-sensitive potassium channel (K(ATP)) openers. 6. Effect of modifications at C6 of benzopyranyl cyanoguanidines.

The effect on potency and selectivity of modifications at the C6 position of the cardioprotective K(ATP) opener BMS-180448 (2) is described. Structure-activity studies show that a variety of electron-withdrawing groups (ketone, sulfone, sulfonamide, etc.) are tolerated for cardioprotective activity as measured by EC(25) values for an increase in time to the onset of contracture in globally ischemic rat hearts. Changes made to the sulfonamido substituent indicate that compounds derived from secondary lipophilic amines are preferred for good cardioprotective potency and selectivity. The diisobutyl analogue 27 (EC(25) = 0.04 microM) is the most potent compound of this series. The cardiac selectivity of 27 results from a combination of reduced vasorelaxant potency and enhanced cardioprotective potency relative to the potent vasodilating K(ATP) openers (e.g., cromakalim). The diisobutylsulfonamide analogue 27 is over 4 orders of magnitude more cardiac selective than cromakalim (1). These results support the hypothesis that the cardioprotective and vasorelaxant properties of K(ATP) openers follow distinct structure-activity relationships. The mechanism of action of 27 appears to involve opening of the cardiac K(ATP) as its cardioprotective effects are abolished by the K(ATP) blocker glyburide.

Thio- and oxoflavopiridols, cyclin-dependent kinase 1-selective inhibitors: synthesis and biological effects.

Flavopiridol analogues, thio- and oxoflavopiridols which contain a sulfur (16) or oxygen (18) atom linker between a chromone ring and the hydrophobic side chain, are selective cyclin-dependent kinase 1 (CDK1) inhibitors with an IC(50) of 110 and 130 nM. These analogues were prepared from key intermediate 7 by substituting the ethyl sulfoxide. Enantio pure intermediate piperidone 10 was obtained from the racemic piperidone 8 via a very efficient "dynamic kinetic resolution" in 76% yield. Hydrophobic side chains such as chlorophenyl or tert-butyl produced potent CDK1 inhibitory activity, while hydrophilic side chains such as pyrimidine or aniline caused a severe reduction in CDK inhibitory activity. These analogues are competitive inhibitors with respect to ATP, and therefore activity was dependent upon the CDK subunit without being affected by the cyclin subunit or protein substrate. Thio- and oxoflavopiridols 16 and 18 are not only selective within the CDK family but also discriminated between unrelated serine/threonine and tyrosine protein kinases. CDK1 selective thio- and oxoflavopiridol analogues inhibit the colony-forming ability of multiple human tumor cell lines and possess a unique antiproliferative profile in comparison to flavopiridol.

Dual metalloprotease inhibitors: mercaptoacetyl-based fused heterocyclic dipeptide mimetics as inhibitors of angiotensin-converting enzyme and neutral endopeptidase.

A series of 7,6- and 7,5-fused bicyclic thiazepinones and oxazepinones were generated and incorporated as conformationally restricted dipeptide surrogates in mercaptoacyl dipeptides. These compounds are potent inhibitors of angiotensin-converting enzyme (ACE) and neutral endopeptidase (NEP) both in vitro and in vivo. Compound 1a, a 7,6-fused bicyclic thiazepinone, demonstrated excellent blood pressure lowering in a variety of animal models characterized by various levels of plasma renin activity and significantly potentiated urinary sodium, ANP, and cGMP excretion in a cynomolgus monkey assay. On the basis of its potency and duration of action, compound 1a (BMS-186716) was advanced into clinical development for the treatment of hypertension and congestive heart failure.

Biphenylsulfonamide endothelin antagonists: structure-activity relationships of a series of mono- and disubstituted analogues and pharmacology of the orally active endothelin antagonist 2'-amino-N- (3,4-dimethyl-5-isoxazolyl)-4'-(2-methylpropyl)[1, 1'-biphenyl]-2-sulfonamide (BMS-187308).

Substitution at the ortho position of N-(3,4-dimethyl-5-isoxazolyl) benzenesulfonamide led to the identification of the biphenylsulfonamides as a novel series of endothelin-A (ETA) selective antagonists. Appropriate substitutions on the pendant phenyl ring led to improved binding as well as functional activity. A hydrophobic group such as isobutyl or isopropoxyl was found to be optimal at the 4'-position. Introduction of an amino group at the 2'-position also led to improved analogues. Combination of the optimal 4'-isobutyl substituent with the 2'-amino function afforded an analogue (20, BMS-187308) with improved ETA binding affinity and functional activity. Compound 20 also has good oral activity in inhibiting the pressor effect caused by an ET-1 infusion in rats. Doses of 10 and 30 micromol/kg iv 20 attenuated the pressor responses due to the administration of exogenous ET-1 to conscious monkeys, indicating that the compound inhibits the in vivo activity of endothelin-1 in nonhuman primates.

Immunopathology of the lens. II. Humoral and cellular immune responses to homologous lens antigens and their roles in ocular inflammation.

It has been possible for the first time to demonstrate antibodies to homologous lens proteins in rabbits without the addition of adjuvant. By means of immunofluorescence and immunoperoxidase methods it has been possible not only to show for the first time that homologous lens antibodies cross-react with extraocular tissues but that the cross-reacting antigens are related to the cell mitochondria, microsomes, and the proteins associated with contractile organelles. The rabbits did not produce antibodies to gamma-crystallins even when the whole lens homogenate was injected with Freund's complete adjuvant. This suggests that gamma-crystallins are non-antigenic in homologous situations, and this may be related to both B- and T-cell tolerance. Alternatively, the failure of gamma-crystallins to induce antibody production may be due to intermolecular antigenic competition with other crystallins. The presence of mycobacteria in an adjuvant is essential for an antibody response to be detectable by agar diffusion techniques. The response to homologous lens antigens, both in magnitude as well as in duration, varied in different rabbits, which suggested to us that a central control mechanism involving the immune response (Ir) genes may plan an important role. Antibodies to homologous lens proteins as detected by immunofluorescence and immunoperoxidase methods were shown to be of the IgG class. This is the first time that the kinetics of the immune response to the same homologous lens antigen in saline with or without incomplete or complete adjuvant has been examined and their relative merits compared. Systemic homologous immunisation followed by discission of the lens led to a marked Arthus type reaction in and around the lens, but a typical granulomatous phakoallergic endophthalmitis was not produced. It seems likely that the rabbit is not suitable for the production of an experimental model of this condition.

Immunopathology of the lens. I. Humoral and cellular immune responses to heterologous lens antigens and their roles in ocular inflammation.

In experimental rabbits heterologous soluble lens proteins consisting of alpha-, beta-, and gamma-crystallins were found to be antigenic; they stimulated a marked antibody response compared to a rather weak T-cell response. The serum antibodies to alpha-crystallins appeared first, to be followed by antibodies to beta- and gamma-crystallins in that order. The rabbits did not respond to heterologous gamma-crystallins unless these were injected with Freund's adjuvant containing mycobacteria. Incomplete Freund's adjuvant (i.e., without mycobacteria) was found to be an inferior immunoaccelerator so far as lens antigens are concerned. The response to lenticular antigens in both magnitude and duration varied in different rabbits, which suggested to us the important role played by a central control mechanism involving the immune response (Ir) genes. Some of the antibodies in potent lens antisera cross-reacted with mitochondria, endoplasmic reticulum (i.e., microsomes), contractile organelles, and cell nuclei. This explains for the first time at least in part the reasons for the widely observed phenomenon of the reactivity of lens antisera with ocular and extraocular structures. Antibodies to soluble lens proteins as detected by immunofluorescence and immunoperoxidase techniques were shown to be of the IgG class. Systemic heterologous immunisation followed by discission of the lens does not lead to the typical changes of phakoallergic endophthalmitis in the rabbit.

Immunopathology of the lens. III. Humoral and cellular immune responses to autologous lens antigens and their roles in ocular inflammation.

In experimental rabbits it has been shown for the first time that autologous lens protein is antigenic when injected with Freund's complete adjuvant. Although lens haemagglutinins were detected in 6 out of 7 rabbits, in only 3 of the 6 animals did the titre reach a maximum of 1:640. A weak agar precipitation reaction was obtained with only 1 of the 3 sera. It would appear, therefore, that the passive haemagglutination test is superior for the detection of autologous lens antibodies. The response to autologous lens antigen both in magnitude as well as in duration varied in different rabbits, which suggested to us the possible role played by a central control mechanism involving the immune-response (Ir) and immune-associated (Ia) genes which are part of the major histocompatibility complex. Alternatively, this variation may be the result of an antigenic competition between various autologous crystallins. Antibodies to autologous lens protein as detected by immunofluorescence and immunoperoxidase techniques were shown to be of the IgG class. Systemic autologous immunisation produces only a mild uveitis and does not lead to a granulomatous intraocular inflammation. Intravitreal injections of autologous lens protein in pre-immunised animals, however, produced an Arthus type of acute endophthalmitis. Autologous lens antisera showed limited cross-reactivity with ocular and extraocular tissues, which could be detected only by such sensitive techniques as immunofluorescence and immunoperoxidase methods.

Genetic toxicological testing of some dyes by the micronucleus test.

Three widely used dyes, acridine orange, blue VRS and fast green FCF were administered to male mice in order to study the induction of gross chromosomal anomalies using the micronucleus test. All 3 compounds were shown to be clastogenic.

The effect of paper industry effluent on growth, pigments, carbohydrates and proteins of rice seedlings.

The effect of paper industry effluent on the growth and content of certain macromolecules of seedlings of rice (Oryza sativa L. cv. Kesari-82K) has been examined. The effects were investigated in relation to both concentration of effluent and time of exposure to the effluent. Percentage of germination, water imbibing capacity, growth, pigment, carbohydrate and protein content showed a decreasing trend with increase in effluent concentration and time. Protein content was the most sensitive macromolecule affected by effluent. Measurement of protein and protein enzymes might therefore provide a useful criterion for the evaluation of the phytotoxicity of effluent released from the pulp and paper industries.

Management of giardiasis by a herbal drug 'Pippali Rasayana': a clinical study.

Pippali Rasayana (PR), an Indian ayurvedic drug prepared from Palash (Butea monosperma (Lamk) Kuntze; Leguminaceae) and Pippali (Piper longum L.; Piperaceae), was administered at a dose of 1 g p.o. three times daily for a period of 15 days to patients (25 treated, 25 placebo controls) suffering from giardiasis with clinical signs and symptoms, and stools positive for trophozoites/cysts of Giardia lamblia. After 15 days of drug treatment there was a complete disappearance of G. lamblia (trophozoites/cysts) from the stools of 23 out of 25 patients. General signs and symptoms of ill health and abdominal discomfort, presence of mucus, pus cells and RBCs were significantly reduced. There was a marked improvement in the clinical and haematological profile of the patients. Spontaneous recovery in 20% cases was recorded in placebo controls.