SUMMARYThe aim of the present study was to assess the recent trends in the epidemiology of non-ty... more SUMMARYThe aim of the present study was to assess the recent trends in the epidemiology of non-typhoidSalmonellain Israel using a sentinel laboratory-based surveillance network. Between 1999 and 2009, 8758Salmonellastool isolates were reported by five sentinel laboratories. There was a significant decrease in the incidence rate ofSalmonellaisolates from 70·5/100 000 in 1999 to 21·6/100 000 in 2005 followed by a slight increase to 30·3/100 000 in 2009. Of allSalmonella, 64·3% were isolated from children in the 0–4 years age group. Up to 2008,S. Enteritidis was the most prevalent serotype and in 2009S. Infantis emerged as the most commonSalmonellaserotype. The decrease in the incidence ofS. Enteritidis andS. Typhimurium and increase inS. Infantis among humans were associated with a similar trend among breeding flocks, which followed significant preventive interventions conducted againstS. Enteritidis andS. Typhimurium infections in poultry. Tight surveillance and education of food han...
A patient transferred from South Africa to Israel acquired a Candida auris infection. Phylogeneti... more A patient transferred from South Africa to Israel acquired a Candida auris infection. Phylogenetic analysis showed resemblance of C. auris to isolates from South Africa but not Israel, suggesting travel-associated infection. C. auris infection occurred weeks later in another patient at the same hospital, suggesting prolonged environmental persistence.
The influence of five antibiotics (netilmicin, ceftriaxone, cefepime, fleroxacin, and ciprofloxac... more The influence of five antibiotics (netilmicin, ceftriaxone, cefepime, fleroxacin, and ciprofloxacin) on capsular polysaccharide distribution and on opsonophagocytosis by human polymorphonuclear leukocytes of unencapsulated and encapsulated Escherichia coli strains was studied. Unencapsulated E. coli strains were readily opsonized in serum and easily ingested by polymorphonuclear leukocytes, and antibiotics did not further enhance the phagocytosis rates. In contrast, encapsulated bacteria were poorly opsonized in human serum, and phagocytosis was enhanced after overnight exposure to 0.5x the MICs of the antibiotics, with the exception of cefepime. Incubation of unencapsulated as well as encapsulated bacteria in complement-inactivated serum markedly reduced the bacterial uptake by polymorphonuclear leukocytes regardless of the presence of antibiotics. Slide agglutination assays, performed either with a monoclonal antibody for capsular polysaccharide or with an antiserum raised against...
SUMMARYThe incidence of invasive infections due toNeisseria meningitidisin Israel is about 1/100 ... more SUMMARYThe incidence of invasive infections due toNeisseria meningitidisin Israel is about 1/100 000 population annually. Three cases of meningococcal meningitis were reported in employees at a single plant; the first case appeared in March 2013 and the second and third cases appeared in December, almost 9 months later.N. meningitidisserogroup B was isolated from cerebrospinal fluid samples. Multilocus sequence typing assigned the three meningococcal isolates to ST10418, a new sequence type and a member of the ST32 clonal complex. The clonality was confirmed by performance of pulsed-field gel electrophoresis. Post-exposure antibiotic prophylaxis was administered to close contacts of the first case. Upon the diagnosis of the additional two cases, post-exposure prophylaxis was administered to all the plant employees. This report demonstrates the importance of combining public health measures and advanced laboratory studies to confirm clonality and to prevent further disease spread in ...
Bone allografting is the most common form of allotransplantation in modern medicine. Bone banking... more Bone allografting is the most common form of allotransplantation in modern medicine. Bone banking is usually the major part of most tissue banks throughout the world. Several years ago, many standards of bone banking were set empirically, and have never been evaluated. One particular parameter or standard was outdating graft materials after 5 years of storage. This study was conducted to evaluate the effect of prolonged cryopreservation on the biomechanical properties of bone allografts and establish whether graft materials become contaminated during long-term storage.Proximal humeral bone allografts were obtained from the bone bank after 1, 3 and 5 years of -80 degrees C cryopreservation. Samples of each humeral head, i.e., cartilage, subchondral bone and spongy bone were histologically examined for inter- and intra-cellular changes. A three-point mechanical bending test was used on identical pieces of cortical bone to compare fresh and cryopreserved materials. Fresh-retrieved cort...
An ongoing nationwide prospective surveillance study was initiated in Israel in October, 1988, to... more An ongoing nationwide prospective surveillance study was initiated in Israel in October, 1988, to document childhood invasive infections caused by Haemophilus influenzae type b (Hib), Streptococcus pneumoniae and Neisseria meningitidis. This study enabled us to document the effect on childhood invasive Hib disease of the introduction of conjugate Hib vaccines to Israel. The incidence of invasive Hib disease before the age of 5 years dropped from 34 per 100000 before initiation of immunization to < 5 per 100000 in 1995 and is projected to be <4 in 1996. After <2 years, when various conjugate vaccines had been available in the private sector alone and had achieved partial coverage only, the Israeli Ministry of Health decided to add Hib conjugate vaccine to the regular infant immunization program, free of charge, effective for all infants born after January 1, 1994. The vaccine chosen was Hib polysaccharide linked to outer membrane protein complex of N. meningitidis B. Vaccine coverage has exceeded 90% of all infants born since January 1, 1994. Efficacy and effectiveness during the first 34 months of the program (January 1, 1994, to October 31, 1996) were 95.4 and 99.7%, respectively, for all invasive Hib disease and 97 and 99.4%, respectively, for Hib meningitis. The described ongoing surveillance program showed the existence and extent of Hib problems in Israel and documented the success of the immunization program in essentially eliminating the disease in Israel.
The failure of antibiotic treatment to eradicate group-A streptococci in up to 30% of patients wi... more The failure of antibiotic treatment to eradicate group-A streptococci in up to 30% of patients with pharyngotonsillitis is unexplained. Some strains of group-A streptococci can enter respiratory epithelial cells, where they would be inaccessible to antibiotics unable to penetrate the cell membrane, such as penicillins. The fibronectin-binding proteins, F1 and SfbI, are needed for this process. We hypothesised, therefore, that an intracellular reservoir of group-A streptococci could account, at least partly, for failure to eradicate throat carriage, and that the presence of the gene for fibronectin-binding protein (F1) might be linked to the ability of a strain to persist in the throat after therapy. We investigated the frequency of prtF1-containing strains among 67 patients with pharyngotonsillitis. All patients were clinically cured, although 13 of them continued to carry group-A streptococci in the throat during or after therapy. To distinguish between persisting and recolonising strains, isolates from the 13 patients were serologically tested and compared by polymorphic DNA-amplification technique. 12 (92%) of the 13 patients with symptomless carriage had prtF1-containing strains in the throat, compared with 16 (30%) of the 54 patients with successful eradication (p=0.0001). Three of the 13 eradication-failure patients were recolonised with strains that differed from the pretreatment strains. Nine of the ten (90%) persisting strains carried prtF1 (p=0.0009). Our findings suggest that protein-F1-mediated entry to cells is involved in the causative process of the carriage state.
Hantavirus pulmonary syndrome (HPS) is a human disease caused by a newly identified hantavirus, w... more Hantavirus pulmonary syndrome (HPS) is a human disease caused by a newly identified hantavirus, which we will refer to as Four Corners virus (FCV). FCV is related most closely to Puumala virus (PUU) and to Prospect Hill virus (PHV). Twenty-five acute HPS serum ...
Journal of visualized experiments : JoVE, Jan 19, 2018
The human intestinal microbiome plays a central role in protecting cells from injury, in processi... more The human intestinal microbiome plays a central role in protecting cells from injury, in processing energy and nutrients, and in promoting immunity. Deviations from what is considered a healthy microbiota composition (dysbiosis) may impair vital functions leading to pathologic conditions. Recent and ongoing research efforts have been directed toward the characterization of associations between microbial composition and human health and disease. Advances in high-throughput sequencing technologies enable characterization of the gut microbial composition. These methods include 16S rRNA-amplicon sequencing and shotgun sequencing. 16S rRNA-amplicon sequencing is used to profile taxonomical composition, while shotgun sequencing provides additional information about gene predictions and functional annotation. An advantage in using a targeted sequencing method of the 16S rRNA gene variable region is its substantially lower cost compared to shotgun sequencing. Sequence differences in the 16S...
SUMMARYThe aim of the present study was to assess the recent trends in the epidemiology of non-ty... more SUMMARYThe aim of the present study was to assess the recent trends in the epidemiology of non-typhoidSalmonellain Israel using a sentinel laboratory-based surveillance network. Between 1999 and 2009, 8758Salmonellastool isolates were reported by five sentinel laboratories. There was a significant decrease in the incidence rate ofSalmonellaisolates from 70·5/100 000 in 1999 to 21·6/100 000 in 2005 followed by a slight increase to 30·3/100 000 in 2009. Of allSalmonella, 64·3% were isolated from children in the 0–4 years age group. Up to 2008,S. Enteritidis was the most prevalent serotype and in 2009S. Infantis emerged as the most commonSalmonellaserotype. The decrease in the incidence ofS. Enteritidis andS. Typhimurium and increase inS. Infantis among humans were associated with a similar trend among breeding flocks, which followed significant preventive interventions conducted againstS. Enteritidis andS. Typhimurium infections in poultry. Tight surveillance and education of food han...
A patient transferred from South Africa to Israel acquired a Candida auris infection. Phylogeneti... more A patient transferred from South Africa to Israel acquired a Candida auris infection. Phylogenetic analysis showed resemblance of C. auris to isolates from South Africa but not Israel, suggesting travel-associated infection. C. auris infection occurred weeks later in another patient at the same hospital, suggesting prolonged environmental persistence.
The influence of five antibiotics (netilmicin, ceftriaxone, cefepime, fleroxacin, and ciprofloxac... more The influence of five antibiotics (netilmicin, ceftriaxone, cefepime, fleroxacin, and ciprofloxacin) on capsular polysaccharide distribution and on opsonophagocytosis by human polymorphonuclear leukocytes of unencapsulated and encapsulated Escherichia coli strains was studied. Unencapsulated E. coli strains were readily opsonized in serum and easily ingested by polymorphonuclear leukocytes, and antibiotics did not further enhance the phagocytosis rates. In contrast, encapsulated bacteria were poorly opsonized in human serum, and phagocytosis was enhanced after overnight exposure to 0.5x the MICs of the antibiotics, with the exception of cefepime. Incubation of unencapsulated as well as encapsulated bacteria in complement-inactivated serum markedly reduced the bacterial uptake by polymorphonuclear leukocytes regardless of the presence of antibiotics. Slide agglutination assays, performed either with a monoclonal antibody for capsular polysaccharide or with an antiserum raised against...
SUMMARYThe incidence of invasive infections due toNeisseria meningitidisin Israel is about 1/100 ... more SUMMARYThe incidence of invasive infections due toNeisseria meningitidisin Israel is about 1/100 000 population annually. Three cases of meningococcal meningitis were reported in employees at a single plant; the first case appeared in March 2013 and the second and third cases appeared in December, almost 9 months later.N. meningitidisserogroup B was isolated from cerebrospinal fluid samples. Multilocus sequence typing assigned the three meningococcal isolates to ST10418, a new sequence type and a member of the ST32 clonal complex. The clonality was confirmed by performance of pulsed-field gel electrophoresis. Post-exposure antibiotic prophylaxis was administered to close contacts of the first case. Upon the diagnosis of the additional two cases, post-exposure prophylaxis was administered to all the plant employees. This report demonstrates the importance of combining public health measures and advanced laboratory studies to confirm clonality and to prevent further disease spread in ...
Bone allografting is the most common form of allotransplantation in modern medicine. Bone banking... more Bone allografting is the most common form of allotransplantation in modern medicine. Bone banking is usually the major part of most tissue banks throughout the world. Several years ago, many standards of bone banking were set empirically, and have never been evaluated. One particular parameter or standard was outdating graft materials after 5 years of storage. This study was conducted to evaluate the effect of prolonged cryopreservation on the biomechanical properties of bone allografts and establish whether graft materials become contaminated during long-term storage.Proximal humeral bone allografts were obtained from the bone bank after 1, 3 and 5 years of -80 degrees C cryopreservation. Samples of each humeral head, i.e., cartilage, subchondral bone and spongy bone were histologically examined for inter- and intra-cellular changes. A three-point mechanical bending test was used on identical pieces of cortical bone to compare fresh and cryopreserved materials. Fresh-retrieved cort...
An ongoing nationwide prospective surveillance study was initiated in Israel in October, 1988, to... more An ongoing nationwide prospective surveillance study was initiated in Israel in October, 1988, to document childhood invasive infections caused by Haemophilus influenzae type b (Hib), Streptococcus pneumoniae and Neisseria meningitidis. This study enabled us to document the effect on childhood invasive Hib disease of the introduction of conjugate Hib vaccines to Israel. The incidence of invasive Hib disease before the age of 5 years dropped from 34 per 100000 before initiation of immunization to < 5 per 100000 in 1995 and is projected to be <4 in 1996. After <2 years, when various conjugate vaccines had been available in the private sector alone and had achieved partial coverage only, the Israeli Ministry of Health decided to add Hib conjugate vaccine to the regular infant immunization program, free of charge, effective for all infants born after January 1, 1994. The vaccine chosen was Hib polysaccharide linked to outer membrane protein complex of N. meningitidis B. Vaccine coverage has exceeded 90% of all infants born since January 1, 1994. Efficacy and effectiveness during the first 34 months of the program (January 1, 1994, to October 31, 1996) were 95.4 and 99.7%, respectively, for all invasive Hib disease and 97 and 99.4%, respectively, for Hib meningitis. The described ongoing surveillance program showed the existence and extent of Hib problems in Israel and documented the success of the immunization program in essentially eliminating the disease in Israel.
The failure of antibiotic treatment to eradicate group-A streptococci in up to 30% of patients wi... more The failure of antibiotic treatment to eradicate group-A streptococci in up to 30% of patients with pharyngotonsillitis is unexplained. Some strains of group-A streptococci can enter respiratory epithelial cells, where they would be inaccessible to antibiotics unable to penetrate the cell membrane, such as penicillins. The fibronectin-binding proteins, F1 and SfbI, are needed for this process. We hypothesised, therefore, that an intracellular reservoir of group-A streptococci could account, at least partly, for failure to eradicate throat carriage, and that the presence of the gene for fibronectin-binding protein (F1) might be linked to the ability of a strain to persist in the throat after therapy. We investigated the frequency of prtF1-containing strains among 67 patients with pharyngotonsillitis. All patients were clinically cured, although 13 of them continued to carry group-A streptococci in the throat during or after therapy. To distinguish between persisting and recolonising strains, isolates from the 13 patients were serologically tested and compared by polymorphic DNA-amplification technique. 12 (92%) of the 13 patients with symptomless carriage had prtF1-containing strains in the throat, compared with 16 (30%) of the 54 patients with successful eradication (p=0.0001). Three of the 13 eradication-failure patients were recolonised with strains that differed from the pretreatment strains. Nine of the ten (90%) persisting strains carried prtF1 (p=0.0009). Our findings suggest that protein-F1-mediated entry to cells is involved in the causative process of the carriage state.
Hantavirus pulmonary syndrome (HPS) is a human disease caused by a newly identified hantavirus, w... more Hantavirus pulmonary syndrome (HPS) is a human disease caused by a newly identified hantavirus, which we will refer to as Four Corners virus (FCV). FCV is related most closely to Puumala virus (PUU) and to Prospect Hill virus (PHV). Twenty-five acute HPS serum ...
Journal of visualized experiments : JoVE, Jan 19, 2018
The human intestinal microbiome plays a central role in protecting cells from injury, in processi... more The human intestinal microbiome plays a central role in protecting cells from injury, in processing energy and nutrients, and in promoting immunity. Deviations from what is considered a healthy microbiota composition (dysbiosis) may impair vital functions leading to pathologic conditions. Recent and ongoing research efforts have been directed toward the characterization of associations between microbial composition and human health and disease. Advances in high-throughput sequencing technologies enable characterization of the gut microbial composition. These methods include 16S rRNA-amplicon sequencing and shotgun sequencing. 16S rRNA-amplicon sequencing is used to profile taxonomical composition, while shotgun sequencing provides additional information about gene predictions and functional annotation. An advantage in using a targeted sequencing method of the 16S rRNA gene variable region is its substantially lower cost compared to shotgun sequencing. Sequence differences in the 16S...
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