Saturday, March 31, 2018

Type Nepali in Unicode Without Internet

Google input tools help you to type Nepali in Unicode without internet. See the tutorial on how to setup Google Input Tools in your PC. How to type Nepali in Unicode without internet (offline), step by step tutorial.

  • Open the file after completing the download process. Run it. It may take a few seconds to minutes to complete the installation.  

Configuration

To use Google Input Tools with other applications, first, open the application and then select the input tool. Google Input Tools can be opened by clicking on the language bar on the desktop, then selecting the input tool language icon. Alternatively, input tools can be enabled using a shortcut key if it has been configured previously. To close an input tool, change the language in the language bar, right-click on the current application to see whether it supports 'Close IME' popup menu option, or just close the current application).

Displaying Language Bar

On the desktop, right-click on the taskbar, then select Toolbars → Language bar

Enabling Language Bar

If the 'Language bar' option is not visible in the 'Toolbars' menu, it needs to be enabled through the Control Panel:

Windows 7/Vista

  1. Navigate to the Control Panel → Regional and Language Options → Keyboard and Languages tab
  2. Click on the Change keyboards… button and open the Text services and input languages dialog
  3. Navigate to Language Bar tab
  4. Enable the radio button Docked in the taskbar under the Language Bar section
  5. Apply all settings, then try to display the language bar as described in the previous section.

Windows XP

  1. Go to Control Panel → Regional and Language Options → Languages tab → Text services and input languages (Details) → Advanced tab
  2. Make sure that under System configuration, the option Turn off advanced text services is not checked.
  3. Go to Control Panel → Regional and Language Options → Languages tab → Text services and input languages (Details) → Settings tab
  4. Click Language Bar
  5. Select Show the Language bar on the desktop. Click OK.
  6. Go to Control Panel → Regional and Language Options → Languages Tab
  7. Make sure that the option Install files for East Asian languages are checked in the checkboxes. This requires the installation of system files and the system will prompt for you to insert the Operating System Disc.
  8. If you are going to install IME for Indic languages or right-to-left languages, also make sure that the option Install files for complex scripts and right to left languages are checked in the checkboxes. This requires the installation of system files and the system will prompt for you to insert the Operating System Disc.
  9. Apply all settings and try to display the language bar as described in the previous section.

Input Tools Shortcut

A shortcut key sequence can be applied to input tools, which can be used to quickly enable them for any in-focus application. To set up a shortcut, follow these steps:

Windows 7/Vista

  1. Control Panel → Regional and Language Options → Keyboard and Languages tab
  2. Click on Change keyboards… button to open Text services and input languages dialog
  3. Navigate to the General tab
  4. If Google [Language] Input is not listed in Installed Services box, then click Add; in the Add Input language dialog box, go to the language for which you want to enable the input tools in the languages tree and expand it. Check the checkbox next to Google [Language] Input in the list.
  5. Navigate to the Advanced key settings tab
  6. In Hot keys for input languages, select To [Language] - Google Input Tools
  7. Press Change Key Sequence
  8. Select Enable Key Sequence
  9. Select a key sequence, such as Left ALT + SHIFT + Key 1
  10. Apply all changes
  11. Test the changes - open an application and press Left ALT + SHIFT + Key 1 (or your custom shortcut) and the input tool should open.

Windows XP

  1. Control Panel → Regional and Language Options → Languages tab → Text services and input languages (Details) → Settings Tab
  2. If either [Language] or Google [Language] Input is not listed in the Installed Services box, then click Add and in the Add Input language dialog box select [Language] in Input language and Google [Language] Input in Keyboard layout/IME. Click OK
  3. Press Key Settings
  4. In Hot keys for input languages, select Switch to [Language]-Google [Language] Input
  5. Press Change Key Sequence
  6. Select Enable Key Sequence
  7. Select a key sequence, such as Left ALT + SHIFT + Key 1
  8. Apply all changes
  9. Test the changes - open an application and press Left ALT + SHIFT + Key 1 (or your custom shortcut) and the input tool should open.

Wednesday, March 28, 2018

Microbiology Research in Nepal

Nepal is a least developed and land locked country. Ecologically it is divided in to Mountain region, Hilly region and Terai region. Majority of population living in remote and village area and these areas are lacking many facilities and there is unplanned urbanization in developed part resulting in lack of health care facilities, places and water supply.

Key facts about HIV/AIDS

  1. HIV continues to be a major global public health issue, having claimed more than 35 million lives so far. In 2015, 1.1 (940 000–1.3 million) million people died from HIV-related causes globally.
  2. There were approximately 36.7 (34.0–39.8) million people living with HIV at the end of 2015 with 2.1 (1.8–2.4) million people becoming newly infected with HIV in 2015 globally.

Quality Control, Risk and Quality Risk Management

Quality : Concepts
What is quality?
It is a multifaceted question, difficult to answer in the abstract. Four fitness that explains the evolution process of quality is
1.   Fitness to standard
2.   Fitness to use
3.   Fitness to cost
4.   Fitness to latent requirement
ISO 9000:2000 and international standard on quality vocabulary define as:
The degree to which a set of inherent characteristics fulfills requirement.
The Americans who brought the messages of quality to Japan and rest of the world. Prominent figures lying on the group are W. Edwards Deming, Joseph M Juran, Philip Crosby
Japanese who developed new concepts to the American messages. Prominent figures lying on this group are: Kaoru Ishikawa, Sigeo Shingo, Yoshio Kondo
Quality Control and Quality Assurance
Quality control is a subset of Quality Assurance
Quality Assurance
“Quality assurance” is a wide-ranging concept covering all matters that individually or collectively influence the quality of a product. It is the totality of the arrangements made with the object of ensuring that pharmaceutical products are of the quality required for their intended use.
Quality Assurance is all those planned and systemic actions necessary to provide confidence that an entity will fulfill requirements for quality. It is a process of creating standards thorough planning. Assurance comes through the knowledge of what will be, is being, of has been done, rather than doing it. The means to provide the confidence, assurance need to build into the process, such as documenting plans, documenting specifications, creating records, reporting reviews etc. Such documents and activities also serve to control quality as well as assure it. ISO 9001 is a quality assurance standard, designed for use in assuring customers that suppliers have a capacity of meeting their requirements. Quality assurance also incorporates Good manufacturing practices (GMP) and other factors.
Quality control
Quality control is operational techniques and activities which are used to fulfill requirements of quality. It is a process of maintaining standards. It prevents the undesirables changes in the quality of product or service being supplied. If you do not have control quality products are produced by chance not design.
What is risk ?
It is commonly understood that risk is defined as the combination of the probability of occurrence of harm and the severity of that harm.
In relation to pharmaceuticals, although there are a variety of stakeholders, including patients and medical practitioners as well as government and industry, the protection of the patient by managing the risk to quality should be considered of prime importance.
It is important to understand that product quality should be maintained throughout the product lifecycle such that the attributes that are important to the quality of the drug product remain consistent with those used in the clinical studies. An effective quality risk management approach can further ensure the high quality of the drug product to the patient by providing a proactive means to identify and control potential quality issues during development and manufacturing.
Product Lifecycle: 1. Introduction, 2. growth, 3. maturity, 3. Decline
What is quality risk management?
Quality risk management (QRM) can improve the decision-making if a quality problem arises. Effective QRM can facilitate better and more informed decisions, can provide regulators with greater assurance of a company’s ability to deal with potential risks, and can beneficially affect the extent and level of direct regulatory oversight.
Quality risk management specifically provides guidance on the principles and some of the tools of quality risk management that can enable more effective and consistent risk-based decisions, by both regulators and industry, regarding the quality of drug substances and drug products across the product lifecycle.
Tools for quality risk management that can be applied to different aspects of pharmaceutical quality. These aspects include development, manufacturing, distribution, inspection, and submission/review processes throughout the lifecycle of drug substances, drug products, biological and biotechnological products (including the use of raw materials, solvents, excipients, packaging and labeling materials in drug products, biological and biotechnological products).
  
Primary Principles of Risk Management
· The evaluation of the risk to quality should be based on scientific knowledge & ultimately link to the protection of the patient and
· The level of effort, formality & documentation of the quality risk management process should be commensurate with the level of risk.
Principles and common practices
Core principles of quality risk management according to the ICH Q9 guideline include the following: International Conference on Harmonization (ICH) provides an excellent high-level framework for the use of risk management in pharmaceutical product development and manufacturing quality decision-making applications
1.    Compliance with applicable laws: Risk assessment should be used to assess how to ensure compliance and to determine the resulting prioritization for action—not for a decision regarding the need to fulfill applicable regulations or legal requirements.
2.    Risk can only be effectively managed when it is identified, assessed, considered for further mitigation, and communicated. This principle embodies the four stages of an effective quality risk-management process as defined by ICH Q9: risk assessment (i.e., risk identification, analysis, and evaluation); risk control (i.e., risk reduction and acceptance); risk communication; and risk review.
3.    All quality risk evaluations must be based on scientific and process-specific knowledge and ultimately linked primarily to the protection of the patient. Risk assessment is based on the strong understanding of the underlying science, applicable regulations, and related processes involved with the risk under analysis. Collectively, these components should be assessed first and foremost with regard to the potential impact to the patient.
4.   Effective risk management requires a sufficient understanding of the business, the potential impact of the risk, and ownership of the results of any risk-management assessment.
5.  The risk assessment must take into account the probability of a negative event in combination with the severity of that event. This principle also serves as a useful working definition for risk (i.e., risk represents the combination of the probability and severity of any given event).
6.   It is not necessary or appropriate to always use a formal risk-management process (e.g., standardized tools). Rather, the use of an informal risk-management process (e.g., empirical assessment) is acceptable for areas that are less complex and that have a lower potential risk. Risk decisions are made by industry every day. The complexity of the events surrounding each decision and the potential risk involved are important inputs in determining the appropriate risk-assessment methodology and a corresponding level of analysis required. For less complex, less risky decisions, a qualitative analysis (e.g., decision tree) of the options may be all that is required. In general, as the complexity and/or risk increases, so should the sophistication of the risk-assessment tool used. In the same regard, the level of documentation of the risk-management process to render an appropriate. 
The Components of the Quality Risk Management Process (ICH Q9)
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Chemicals from gut bacteria maintain vitality in aging animals

Indoles help worms/flies/mice live stronger for longer.

A class of chemicals made by intestinal bacteria, known as indoles, help worms, flies and mice maintain mobility and resilience for more of their lifespans, scientists have discovered.
Bacterial colony on culture media (file photo)
The findings are scheduled for publication August 21 in PNAS.
"This is a direct avenue to a drug that could make people live better for longer," says senior author Daniel Kalman, PhD, professor of pathology and laboratory medicine at Emory University School of Medicine.
Kalman and his colleagues use the term "healthspan" to describe the length of time a human or animal, while aging, can stay active and resist stress. In this research, the focus is on whether the animals live healthier, but not necessarily longer.
"We need a better understanding of healthspan," he says. "With medical advances, people are living longer; but you might not really want to live longer if it means spending those extra years frail and infirm." The burden imposed by diseases of aging on the healthcare system is expected to skyrocket in coming decades, he adds.
Interest in the health effects of the microbes that live in our bodies has exploded in recent years. In humans and mice, some studies have shown that the spectra of bacteria in our bodies become narrower with age.
"We don't always know how various microbiota exert their effects," Kalman says. "But now we have a big clue to one mechanism."
Indole, produced by many types of bacteria through breakdown of the amino acid tryptophan, can smell noxious or flowery depending on the concentration. Indole and its chemical relatives can be found in plants, especially vegetables such as broccoli and kale. One such relative is also known as auxin, a growth hormone for plants needed for light-seeking and root development.
Kalman's lab had previously identified indole and related molecules as compounds released by E. coli bacteria that condition the worm C. elegans and mice to be more resistant to infection and other stresses.
The roundworm C. elegans is one of the premier organisms in which to study aging. Studies in C. elegans led to discovery of a set of genes that control how long the worms can live. Several of the genes are components of the insulin signaling pathway, and they influence lifespan in flies and mice as well.
Worms normally eat bacteria. So researchers fed them E. colibacteria that produce indoles, and compared them with worms fed E. coli that cannot produce indoles.
As they age, older worms spend less time moving around, can't swallow as well and are more sensitive to stressors. Although indoles didn't change the maximal lifespan, they markedly increased the amount of time worms were mobile after the age of 15 days, and it increased their swallowing strength and resistance to heat stress, even in young animals.
In addition, worms usually stop reproduction at the age of 5 days, but dietary indole more than doubled their reproductive span, allowing them to remain fertile up to 12 days.
Indole had similar effects on mobility and resistance to heat in Drosophila fruit flies, and with mice, a comparable pattern was evident. Researchers treated mice with antibiotics to eliminate the existing flora, and then re-colonized them with either normal E. coli, or, as a control, with bacteria that cannot produce indole. In very old mice (28 months), indoles helped animals maintain their weight, mobility and activity levels. In younger mice, indoles extended survival after exposure to lethal radiation.
The researchers also analyzed the patterns of gene activity affected by indoles -- the genes regulated by indoles were distinct from other C. elegans genes previously linked to longevity.
"It's like the Picture of Dorian Gray, in terms of the genes involved," Kalman says. "Indoles make old animals look more like the young ones."
Indoles may be keeping the intestinal barrier intact and/or limiting systemic inflammatory effects. Kalman's laboratory is now investigating how indoles exert their effects in aging animals, how dysregulation of indoles produced by the microbiota contribute to frailty, and how indoles can be used to reverse these effects.
"Indole is such an ancient messenger," Kalman says. "It's how plants steer their growth, how bacteria talk to each other, and it is how plants and bacteria talk with us and ensure proper homeostasis with our immune system. It is perhaps not so surprising that these molecules help maintain our vitality."
The first author of the paper is postdoctoral fellow Robert Sonowal, PhD. Co-authors include professor of pathology Guy Benian, PhD, assistant professor of pediatrics Rheinallt Jones, PhD, and professor of geriatrics Jonathan Flacker, MD.
The research was supported by the Bio-Merieux Foundation, the National Institute for Diabetes and Digestive and Kidney Diseases (DK074731) and the National Institute on Aging (AG054903).
Story Source:
Materials provided by Emory Health SciencesNote: Content may be edited for style and length.

Journal Reference:
  1. Robert Sonowal, Alyson Swimm, Anusmita Sahoo, Liping Luo, Yohei Matsunaga, Ziqi Wu, Jui A. Bhingarde, Elizabeth A. Ejzak, Ayush Ranawade, Hiroshi Qadota, Domonica N. Powell, Christopher T. Capaldo, Jonathan M. Flacker, Rhienallt M. Jones, Guy M. Benian, and Daniel Kalman. Indoles from commensal bacteria extend health spanPNAS, August 21, 2017 DOI: 10.1073/pnas.1706464114

SALMONELLA - Morphology, Laboratory diagnosis, Cultural characteristics

SALMONELLA

Salmonella with peritrichous flagella. 
The Salmonella are facultative anaerobic Gram-negative bacilli, motile, non‐capsulated, non-sporing organism. Salmonella currently comprises of about 2,500 serotypes or species. All of them are potentially pathogenic Salmonella produce 3 main types of diseases in human.  These are enteric fever, food poisoning (Gastroenteritis) and Septicaemia. Most of the other Salmonella are chiefly pathogenic in animals like poultry, pig, rodent, cattle, parrot and other.

Morphology 

Salmonella is gram-negative bacilli arranged mainly singly or in pairs. It is non‐capsulated, non‐sporing. Most of the strains are motile due to the presence of peritrichous flagella except S. Gallinarum and S. Pullorum, which are non‐motile. Measuring 1‐3 μm long 0.6 μm wide.

Taxonomy of the Salmonellae

The problems involved in the taxonomy and nomenclature of this group of bacteria g p can only be understood in the historical perspective. At first, the genus Salmonella appeared to comprise species that differed only in their antigen structures. Species names were therefore used for what turned out to be serovars. More recent molecular studies have demonstrated that the genus Salmonella contains only two species that can be subdivided into seven subspecies. All of the important human pathogen salmonellae belong to the subspecies enterica. The (false) species names for the serovars had, however, already become normal usage. In view of the fact that the causative pathogens in typhoid salmonelloses, a clinical picture clearly differentiated from Salmonella gastroenteritis, are only serovars of the same species/ subspecies, the official committee has, however, not adopted the new nomenclature as yet.

Current nomenclature system

All antigenic formulae of recognized Salmonella serovars are listed in the White‐Kauffmann‐Le Minor scheme, and newly recognized serovars are reported every year in the journal Research in Microbiology. The nomenclature system used at the United States Centers for Disease Control and Prevention (CDC) is based on recommendations from the WHO Collaborating Centre, which is responsible for regular updates of the scheme.
In order to avoid unnecessary confusion between serovars and species, the serovar name is not italicized and starts with a capital letter. As not all serovars have a name, for those designated by their antigenic formulae the subspecies name is written in Roman letters, followed by their antigenic formulae – including O (somatic) and both phase 1 and phase 2 H (flagellar) antigens.
Approximately 60% of all Salmonella serotypes belong to Salmonella enterica subspecies enterica. Within this subspecies, the most commonO‐antigen serogroups are A, B, C1, C2, D and E. It must be noted that strains in these serogroups cause approximately 99% of Salmonella infections in humans and warm‐blooded animals.
The nomenclature of the genus Salmonella has evolved from the initial one serotype‐one species concept proposed by Kauffmann on the basis of the serologic identification of 'O' (somatic) and 'H' (flagellar) antigens.
  • Each serotype was considered a separate species (for example Salmonella paratyphi A, Salmonella newport and Salmonellaenteritidis); this concept, if used today, would result in 2463 species of Salmonella.
  • The defining development in Salmonella taxonomy occurred in 1973 when Crosa et al., demonstrated by DNA‐DNA hybridization that virtually all Salmonella belonged in a single species name Salmonella enterica which is separated into 7 distinct subspecies. Most of the serotypes that cause human diseases are in subgroup I.The single exception is Salmonella bongori which was made that there be only 2 species of Salmonella, Salmonella enterica (include the 2462 Serovars previous species) and Salmonella bongori
Antigenic structure Salmonella possesses the following antigens based on which they are classified and identified :
  1. Flagellar (H) antigen
  2. Somatic (O) antigen
  3. Capsular (K) Antigen
The serovars are determined by O and H antigens. The Kauffman–White scheme is used to arrange them (see Table). This taxonomic arrangement classifies the serovars in groups characterized by certain O antigens (semibold).
This results in a clinically and epidemiologically useful grouping since certain serovars are responsible for typhoid salmonelloses and others for enteric salmonelloses. The serovars are determined by means of antisera in the slide agglutination test. Phase Variations of the H Antigens H antigens occur with two different antigen structures. The primary structure of flagellin is determined by two genes on the chromosome, only one of which is read off. Whether a gene is read off or not is determined by spontaneous inversion of a DNA sequence before the H2 gene, which inversion occurs with a frequency of approximately 10–4 per cell division.
O antigen
Characteristics of somatic (O) antigen:
  • The somatic O antigen is a phospholipid protein-polysaccharide complex, which forms a part of the cell wall.
  • It can be extracted from the bacterial cell by treatment with phenol or alcohol.
  • The O antigen is unaffected by boiling, alcohol or weak acids.
  • It is present both in motile and non‐motile Salmonella.
  • For serological test (Widal test) "O" suspension is prepared either from non‐motile strains or by heat or alcohol treatment of motile strains, which destroy H antigen.
  • When mixed with antiserum "O" antigen suspensions produce compact, chalky granular.
  • The optimum temperature for "O" agglutination is at 50‐55°C.
  • The "O" antigen is less immunogenic than H antigen.

H antigen

Characteristics of flagellar (H) antigen:
  •  This antigen is present on the flagella of the bacterium.
  • It is hat labile protein.
  • It is destroyed by boiling or by treatment with alcohol but not formaldehyde.
  • For serological test (Widal test) H suspension is prepared by addition of formalin to young motile broth culture.
  • When mixed with anti‐serum, H suspension agglutinate rapidly and producing large loose floccules.
  • The H antigen is strongly immunogenic and induces antibody formation rapidly in high titre following infection.
  • The optimum temperature for H agglutination is at 37°C.

VI antigen

Characteristics of (Vi) antigen:
  • Vi‐antigen is external to the cell wall.
  • Vi‐antigen is a virulent (Vi for virulence) for mice.
  • Vi‐antigen interferes with agglutination of the freshly isolated organism by "O" antigen.
  • It is a polysaccharide in nature and heat-labile.
  • It destroyed by boiling for one hour.
  • It is not affected by 2% formalin and alcohol.
  • It is lost on serial subcultures.
  • It produces low titre antibody

    Virulence factors

    • Type III secretion systems (bacterial proteins): Two separate type III secretion systems of bacterial proteins mediate the initial invasion of Salmonella into the mucosa of small intestine Other factors
    • Invasins: Invasins are proteins that mediate adherence to, and penetration of, intestinal epithelial cells. Synthesis of these fimbrial proteins by the bacterial cells is under the control of inv genes.
    • Factors involved in resistance to acid pH: Acid tolerance response (ATR) gene of chromosome
    • Vi (virulence) antigen: The surface antigen (Vi antigen) has antiphagocytic properties.

    Clinical manifestations

    The signs and symptoms of enteric fever are

    1. Gradually increasing fever
    2. Mental clouding of consciousness (typhus means cloud)
    3. Malaise
    4. Headache
    5. Constipation
    6. Coated tongue
    7. Anorexia
    8. Splenohepatomegaly 
    9. Bradycardia (Slow heart rate) 
    10. Rose spots may appear on chest and abdomen in 2nd and 3rd week of infection.

    Laboratory diagnosis

     Specimen collection
    • Blood, urine, stool, bone marrow, and aspirated duodenal fluid are suitable specimens for diagnosis of typhoid fever.

    Pathogenesis

    • Salmonella is strict parasites of animals or human beings. It causes enteric fever, septicemia, and gastroenteritis.
    • Enteric fever is most usually caused by Salmonella Typhi or Salmonella Paratyphi A, B or C but can be caused by any Salmonella serotypes.
    • Enteric fever is potentially life-threatening systemic illness characterized by high fever and abdominal complaints. The term enteric fever encompasses both typhoid and paratyphoid fever.
    • Enteric fever is a generalized acute infection characterized by cyclic course, definitive temperature curve, general intoxication, bacteraemia and affection of the lymphatic apparatus of the small intestine through which the infection implants itself in the host upon entrance of the causative agent into the gastrointestinal tract.

    Virulence factors

    • Type III secretion systems (bacterial proteins): Two separate type III secretion systems of bacterial proteins mediate the initial invasion of Salmonella into the mucosa of small intestine Other factors
    • Invasins: Invasins are proteins that mediate adherence to, and penetration of, intestinal epithelial cells. Synthesis of these fimbrial proteins by the bacterial cells is under the control of inv genes.
    • Factors involved in resistance to acid pH: Acid tolerance response (ATR) gene of chromosome
    • Vi (virulence) antigen: The surface antigen (Vi antigen) has antiphagocytic properties.

    Clinical manifestations

    The signs and symptoms of enteric fever are:
    1. Gradually increasing fever
    2. Mental clouding of consciousness (typhus means cloud)
    3. Malaise
    4. Headache
    5. Constipation
    6. Coated tongue
    7. Anorexia
    8. Splenohepatomegaly
    9. Bradycardia (Slow heart rate)
    10. Rose spots may appear on chest and abdomen in 2nd and 3rd week of infection.

    Microscopic examination

    Microscopic examination of Gram staining smear shows Gram-negative bacilli arranged mainly in single.

    Cultural characteristics

    It is aerobic and facultatively anaerobic. The range of temperature for growth is 15‐41°C and optimum pH for growth is 6.8. Grow on a general purpose or basal medium.

    MacConkey agar

    Specimens are inoculated into the MacConkey agar; incubate at 37°C for 24 hours. The colonies are large 2‐3 mm in diameter, circular, low convex, smooth, translucent, colourless due to non‐lactose fermentation.

    Broth medium

    It produces uniform turbidity, no pellicle formation.

    Blood agar

    Colonies are large 2‐3 mm in diameter, colourless, circular, low convex, translucent, smooth and non‐haemolytic.

    Deoxycholate citrates agar (DCA)

    Salmonellae produce non‐lactose fermenting pale coloured colonies, which have the black centre on DCA due to H2S production.

    ENTEROCOCCUS: Morphology, Lab Diagnosis and Control

    Streptococcus colony (file photo)

    Enterococcus/Group D Streptococcus:

    Group D Streptococci

    • Former Lancefield Group D is classified in 1980 into two groups.

    Enterococci

    • Fecal Streptococci has been reclassified as separate Genus called Enterococcus- containing different species, such as Enterococcus faecalis, Enterococcus faecium.
    Non-Enterococcal Group D
    Streptococcus bovis
    Enterococci
    • Enterococci contain cell wall polysaccharide that reacts with group D antisera. Therefore, in the past, they were considered group D streptococci. Today, DNA analysis and other properties have placed them in their own genus, Enterococcus.
    • The clinically most important species are E.faecalis and E. faecium. Enterococci can be Alpha, Beta, or nonhemolytic. As a rule, enterococci are not very virulent, but they have become prominent as a cause of nosocomial infections due to their multiple antibiotic resistance.

    Enterococcus faecalis

    • Enterococcus faecalis is the main pathogen in the genus Enterococcus, causing about 95% of enterococcal infection.

    Morphology

    • They are Gram‐positive cocci arranged in pairs or short chains. They are non-capsulated.

    Pathogenesis

    • Enterococci are a commensal organism and do not have potent toxin and well-defined virulence factors.
    • Their greatest significance is their resistance to many commonly used antibiotics.

    Disease:

    It produces:
    1. Urinary tract infection
    2. Biliary tract infection
    3. Ulcers (e.g. bed sores)
    4. Wound infection (particularly abdominal)
    5. Occasionally endocarditis and meningitis

    Laboratory diagnosis

    Specimen collection: Possible pathological specimens are
    1. Urine
    2. Pus swab
    3. Blood
    4. CSF.
    Microscopic examination:
    • Microscopic examinations of Gram‐staining smear shows Gram‐positive cocci in pairs or in short chains.
    Culture characters: 
    • Enterococci are aerobic; organisms are capable of growing a wide range of temperature (10‐45°C). They can withstand heat at 60°C for 30 minutes. Grow at pH 9.6, and 6.5 % NaCl broth. Grow at 40 % Bile.
    Blood agar: 
    • Enterococci are generally non-hemolytic but some strains show alpha or beta hemolysis.
    Fig: Enterococcus facalis in blood agar
    MacConkey agar: 
    • E. faecalis ferments lactose, produce small, dark‐red colonies.
    Bile Esculin Agar:
    • Produces black colored colonies due to hydrolysis of esculin to esculetin which forms the black precipitate.
    Cysteine lactose electrolytedeficient agar (CLED): 
    • It produces small yellow colonies on CLED agar.

    Biochemical reactions

    • Enterococci are distinguished from the non‐Group D streptococci by their ability to survive in the presence of bile and to hydrolyze the polysaccharide esculin.
    • Unlike non-enterococcal group D streptococci, enterococci grow in 6.5 percent NaCl and yield a positive PYR test.
    • E. faecalis can be distinguished from E. faecium by their fermentation patterns, which are commonly evaluated in clinical laboratories.

    Treatment

    • Most Enterococci are sensitive to ampicillin and resistant to cephalosporin.

    Antibiotic Resistance

    • A major problem with the enterococci is that they can be very resistant to antibiotics. E faecium is usually much more antibiotic‐resistant than E. faecalis.
    • Enterococci are naturally resistant to BetaIactam antibiotics and aminoglycosides but are sensitive to the synergistic action of a combination of these classes. In the past, the initial regimens of choice were penicillin + streptomycin, or ampicillin + gentamicin.

    Vancomycin Resistance

    • The glycopeptide vancomycin is the primary alternative drug to a penicillin (plus an aminoglycoside) for treating enterococcal infections. These enterococci are not synergistically susceptible to vancomycin plus an aminoglycoside. Vancomycin resistance has been most common in E faecium, but vancomycin‐resistant strains of E. faecalis also occur.
    • The gene encoding for the enterococcal Beta‐lactamase is the same gene as found in Staphylococcus aureus. The gene is constitutively expressed in enterococci and inducible in staphylococci. Because enterococci may produce small amounts of the enzyme, they may appear to be susceptible to penicillin and ampicillin by routine susceptibility tests

     NON-ENTEROCOCCAL GROUP D STREPTOCOCCI

    • Streptococcus bovis is the most clinically important of the non-enterococcus group D streptococci. Part of normal fecal flora, they are either alpha‐ or nonhemolytic. S. bovis occasionally causes urinary tract infections and subacute bacterial endocarditis, especially in association with bowel malignancy. 
    • The organism is bile‐ and esculin positive, but is PYR‐negative, and does not grow in 6.5 percent salt (unlike the enterococci). It tends to be sensitive to penicillin and other antibiotics.