, 1996). Stationary phase cells also contained 3–4 genomes per cell. Therefore, in S. elongatus, the ploidy www.selleckchem.com/products/epacadostat-incb024360.html level is not growth phase-regulated, in contrast to many other species. The results of genome quantification for Synechococcus WH7803 are also summarized in Table 1. This species also contained between three and four genome copies at an OD750 nm of 0.6 and during stationary phase, and is thus oligoploid. Again, this is in accordance with

an earlier study that applied FACS analysis for genome copy number determination and found 2–4 copies per cell (Binder & Chisholm, 1990). Taken together, the freshwater as well as the salt water species were found to be oligoploid, irrespective of the applied method for quantification (based either on www.selleckchem.com/Proteasome.html one specific site of the genome (this study) or the average DNA content), growth in continuous light (this study) or growth in light–dark cycles (Mori et al., 1996), and the growth phase. First, the motile Synechocystic PCC 6803 wild-type strain was analyzed. An average growth curve of three independent cultures is shown

in Fig. S3. The results of genome copy number determination are summarized in Table 2. The doubling time at the cell harvest in linear growth phase (OD750 nm = 0.6) was around 20 h. Synechocystis PCC 6803 turned out to be highly polyploid, and it contained nearly 60 genomes per cell, both in linear and in stationary growth phase. As this value is very high and in fact higher than any value published until now for any cyanobacterial species, the genome copy number in stationary phase cells was also determined using an independent method, namely spectroscopic determination of the DNA concentration. The average values of 57.9 Thymidine kinase (if the plasmid copy number would be low) and 53.3 (if the plasmid copy number would be high) genomes per cell were in excellent agreement with the real time PCR result, and thus underscored that Synechocystis PCC 6803 is highly polyploid. An earlier study had also shown that this species is polyploid, but the reported value of 12

genome copies per cell for the ‘Kazusa’ wild-type of Synechocystis PCC 6803 (Labarre et al., 1989) is much lower than the value determined in this study. The reason for the discrepancy is not obvious, as in the previous study also the lysis efficiency was quantified, genome size was underestimated by only 32%, and the colorimetric assay for DNA quantification probably cannot be that wrong. The same medium was used, and a similar doubling time of 15–20 h was reported. Therefore, it might be that both reports are correct and that the ploidy level of various strains of the species Synechocystis PCC 6803 are different. To test this hypothesis, another wild-type strain of Synechocystis PCC 6803 was used, i.e. the so-called GT wild-type.

Group 1 was on TDF for about 20 months longer than group 2, and even in this relatively small number of patients there was a trend for a correlation between the duration of TDF use and TmP/gfr (R = −0.33; P = 0.065). Although

the evidence is not very strong, it suggests at least some deleterious drug effect on phosphate reabsorption. However, as hypophosphataemic patients also had HIV infection for a longer period, an effect of the infection itself cannot be excluded with certainty. Serum 25-OHD, 1.25-OHD, the 1.25-OHD/25-OHD ratio, and PTH and FGF-23 levels were similar in the two groups. Two statistically significant biochemical differences between the groups emerged: group 1 had a much lower calcium excretion rate (2.1 ± 0.03 vs. 4.4 ± 0.6 mmol/24 h, respectively; P < 0.002) and a lower plasma PINP level (48.0 ± 3.1 vs. 61.9 ± 5.8 μg/L, respectively; P < 0.01). The reduced calcium Vorinostat chemical structure excretion could be explained by the lower calcium intake in this group. The inverse correlation between PINP level and TDF use (R = −0.34; P < 0.05) suggests that HAART may have some suppressive effect on bone formation. Such an effect has been observed in mice in which reduced osteoblast gene expression was seen after exposure to TDF [18]. In humans, protease inhibitors and tenofovir have been associated with reduced bone density [19]. PTH and FGF-23 are the key hormones regulating renal phosphate handling. An excess

of each of these hormones will cause a decrease in TmP/gfr, which will lead to renal phosphate loss and hypophosphataemia. Our results clearly demonstrate that hyperphosphaturic hypophospataemia in HIV-positive BIBW2992 manufacturer tenofovir-treated patients cannot be explained by elevated FGF-23

levels. Serum FGF-23 was in the normal range in both groups, there was no correlation between FGF-23 selleck kinase inhibitor level and TmP/gfr, and 1.25-OHD levels were not inappropriately low. Therefore, other factors must be responsible for the observed phosphaturic effect. PTH itself is not a likely candidate as there was no difference in PTH levels between hypo- and normophosphataemic HIV-positive patients, and a correlation between PTH and TmP/gfr was lacking. Vitamin D deficiency is a common cause of hypophosphataemia. High rates of vitamin D deficiency have been reported in HIV-infected patients, with prevalences ranging between 20 and 75% [4, 6, 7]. Vitamin D deficiency is particularly common in patients on nonnucleoside reverse transcriptase inhibitors (NNRTIs) such as efavirenz. These drugs are known to induce cytochrome P450 3A4 (CYP3A4), the enzyme that catalyses 25-OHD and thus will tend to reduce serum 25-OHD [6, 20]. Reduced serum phosphate levels in vitamin D deficiency are caused by renal phosphate loss induced by secondary hyperparathyroidism (SHPT), as well as by reduced intestinal phosphate absorption as a result of relatively low 1.25-OHD levels caused by limited production as a result of reduced substrate availability.

, 2003; Spiers & Rainey, 2005). The involvement of iron in the control of dispersal suggests a role for genes regulated via Fur (Pennella & Giedroc, 2005); however, the impact of other metal ions suggests the involvement of an additional regulatory mechanism. It is tempting to speculate that there may be a role for a metal ion-activated Bortezomib purchase phosphodiesterase (which would degrade cyclic di-GMP) (Bobrov et al., 2005). In addition, we note that UPEC 536 does aggregate in both R and RF during the first few hours of growth following inoculation (Fig. 1), suggesting that in addition to the provision of iron there may be regulatory input associated with entry into the stationary phase (Hengge, 2008) and/or

quorum sensing (Walters & Sperandio, 2006). Iron has been shown to regulate biofilm equilibrium in other bacterial species in ways different from that observed here with UPEC. For example, iron is necessary for biofilm formation by Pseudomonas aeruginosa, and increasing the FeCl3 concentration

up to 10 μM (the concentration used in this study) steadily increases biofilm formation Selleckchem FDA-approved Drug Library (Banin & Greenberg, 2008). In P. fluorescens, the provision of iron (0.1–5 μM), and of copper, lead, and manganese, promotes the production of a cellulosic biofilm matrix with a weak, easily disrupted structure. The provision of higher levels of iron (50 μM) results in the production of a stronger cellulose matrix (Koza et al., 2009). The divergent effects of biofilm responses to the available iron may reflect important differences in the ecology of the bacterium and its host interaction that we do not yet understand. In a UPEC infection scenario where bacteria are successful in the struggle for iron, our results support the initiation of dispersion from the cellulose matrix, which we propose may involve the release Cyclic nucleotide phosphodiesterase of glucose from cellulose that can be used an energy source and that may also affect subsequent gene expression mediated by cAMP–CAP (Weyand et al., 2001). To conclude, it is important

to consider the implications of cellulose as part of the IBC/QIR matrix. Iron starvation of UPEC induces the synthesis of the cellulose matrix with properties that will aid attachment (Wang et al., 2006; Saldaña et al., 2009), and presumably provide a protective matrix favouring survival in the presence of both antibiotics and immune defences. Rosen et al. (2007) found a clear association with the presence of IBCs in urine and a UPEC UTI. IBCs were not found in the urine of uninfected individuals, and those infected with other species of bacteria. We found that seven of 12 clinical isolates (two of the nonaggregative isolates were from asymptomatic patients) formed aggregates when cultured in R, in agreement with the finding that many pathogenic isolates form cellulose at 37 °C (Bokranz et al., 2005; Da Re & Ghigo, 2006; Monteiro et al., 2009). Given that Reisner et al. (2006) found no association with the ability of E.

bovis BCG and M. smegmatis is blocked in the ATP hydrolysis mode and is not able to generate a PMF by hydrolyzing ATP. The essentiality of ATP synthase is thus based on a function in the synthesis direction, GSK J4 research buy most likely either for the production of ATP, pH homeostasis, or for contributing to the NAD+/NADH redox balance. The task of PMF maintenance under low oxygen tensions is most probably fulfilled by other membrane–protein complexes, such as by nitrate reductase or by fumarate reductase acting in reverse (Schnorpfeil et al., 2001; Wayne & Sohaskey, 2001). In order to gain an insight into the mechanism of ATP hydrolysis blockage

in mycobacteria, we tested the effect of four different treatments reported to activate ‘latent’ ATP hydrolysis activity in bacteria. Limited trypsin proteolysis is reported to cleave the inhibitory intrinsic subunit ɛ and in this way activate ATP hydrolysis (Bogin et al., 1970; Keis et al., 2006), while the addition of methanol is thought to compromise hydrophobic interactions within ATP synthase (Hisabori et al., 1997). Moreover, oxy-anions,

for example sulfite, are reported to remove inhibitory ADP and to uncouple ATP synthase function (Bakels et al., 1994; Cappellini et al., 1997; Pacheco-Moisés et al., 2002). Finally, membrane energization is known to relieve ADP inhibition and to switch the conformation of subunit ɛ to a noninhibitory Selleck Trichostatin A state (Suzuki et al., 2003). The ATP hydrolysis activity of IMVs of M. smegmatis was indeed activated >30-fold by trypsin (Table 2), indicating that subunit ɛ is an important determinant for ATP hydrolysis blockage in this fast-grower. However, in the case of M. bovis BCG, trypsin treatment did not lead to significant activation (Table 2). This lack of activation can be explained either by

inaccessibility of the trypsin cleavage site or by the presence of alternative inhibitory mechanisms. To further investigate ATP hydrolysis in M. bovis BCG, we tested the effect of methanol, sodium sulfite and PMF activation. Whereas sulfite slightly activated ATP hydrolysis activity, both addition of methanol and membrane energization by succinate led to more significant activation for M. bovis BCG, with the resulting activity ∼10-fold higher than the ATP synthesis activity (Table 2). Dipeptidyl peptidase The results suggest that ATP hydrolysis in both slow-growing as well as fast-growing mycobacteria is regulated in a PMF-dependent manner, preventing excess ATP consumption under low oxygen tensions. Suppression of activity appears to be more pronounced in the slow-grower, which may be an adaptation to environments with a low energy supply and/or decreased oxygen tensions, for example in remote parts of the mammalian lungs. mycobacteria, requiring oxygen for growth, but able to persist under anaerobic conditions, thus utilize a similar mechanism of ATP hydrolysis inhibition as reported for the obligate aerobic bacteria P.

This research was funded by Polish Ministry of Science and Higher Education (Grant No. N304 020437). “
“The High Taxonomic Fingerprint (HTF)-Microbi.Array is a fully validated phylogenetic microarray platform for a high taxonomic level characterization of the human gut microbiota. However, suffering from PCR-dependent biases in Bifidobacterium quantification, this tool is less appropriate when utilized for the characterization of the Bifidobacterium-dominated gut microbiota of breast-fed infants. To overcome this, we implemented a new combined approach based on HTF-Microbi.Array and qPCR for a reliable check details fingerprint of the infant-type microbiota. This methodology was applied in a preliminary comparative study of

the faecal microbiota of eight breast-fed infants, aged 2–6 months, and five young adults. Whereas the adult gut microbiota was Selleck Daporinad largely dominated by Firmicutes and Bacteroidetes, the infant-type community was mainly dominated by Bifidobacterium,

with Enterobacteriaceae as the second dominant component. In accordance with the most recent literature in the field, the obtained microbiota fingerprints properly depicted the adult- and the infant-type microbiota, demonstrating the reliability of the HTF-Microbi.Array/qPCR combined approach in reflecting the peculiarities of the two intestinal microbial ecosystems. “
“Glutathionylspermidine synthetase/amidase (Gss) and the encoding gene (gss) have only been studied in Escherichia coli and several members of the Kinetoplastida

phyla. In the present article, we have studied the phylogenetic distribution of Gss and have found that Gss sequences are largely limited Bacterial neuraminidase to certain bacteria and Kinetoplastids and are absent in a variety of invertebrate and vertebrate species, Archea, plants, and some Eubacteria. It is striking that almost all of the 75 Enterobacteria species that have been sequenced contain sequences with very high degree of homology to the E. coli Gss protein. To find out the physiological significance of glutathionylspermidine in E. coli, we have performed global transcriptome analyses. The microarray studies comparing gss+ and Δgss strains of E. coli show that a large number of genes are either up-regulated (76 genes more than threefold) or down-regulated (35 genes more than threefold) by the loss of the gss gene. Most significant categories of up-regulated genes include sulfur utilization, glutamine and succinate metabolism, polyamine and arginine metabolism, and purine and pyrimidine metabolism. Earlier work from this laboratory showed that 95% of the intracellular spermidine and a large fraction of the intracellular glutathione are converted to monoglutathionylspermidine in Escherichia coli at the end of logarithmic growth (Dubin, 1959; Tabor & Tabor, 1970). Bollinger et al. (1995) and Kwon et al. (1997) reported the purification of glutathionylspermidine synthetase/amidase of E.

5%) for morphine sulphate injection. Lack of appreciation

of the overage in morphine ampoules by healthcare professionals, mainly in theatres. Administering infusions to children requires complex dose calculations, infusion rate adjustments and often requires several GDC-0941 mouse manipulations of injectable medicines to obtain the final “ready to use” infusion solution. This system is high risk in terms of administration and consequent serious adverse events.1 Errors in intravenous drug preparations involving the wrong diluent or volume / dose or wrong infusion rate are common.2 The aim of this study was to investigate current practice preparing morphine infusions for nurse/patient-controlled analgesia (N/PCA) in a UK children hospital. Prospective observational study of current practice in preparing morphine N/PCA was carried out over three months (21/05–16/08/13) at one UK children hospital. A pharmacist, researcher observed healthcare professionals (HCPs), nurses and doctors, preparing N/PCA infusions in paediatric theatres and wards. The data collection form included; patient demographics, prescription Dabrafenib in vitro and preparation

process details. Descriptive analysis was performed using stata software. In order to assess the accuracy of the final product of morphine infusion, a sample of 78 used syringes prepared in theatre or on the ward were analysed using by UV-Vis Spectrophotometer (Varian Cary®) by the Trust’s Quality Control (QC) department. Measured concentration was then compared to the

British Pharmacopoeia (BP) acceptable limits for morphine sulphate injection of ±7.5% of the labelled strength (LS), i.e. prescribed dose. This study received Trust Research and Development approval. Ethics approval was not required as data collection was part of a service development to consider the use of standard morphine concentrations for N/PCA. In total 153 individually prepared syringes by HCPs for 128 children [mean age (±SD) 7.5 years ± 5.6; 65.3% male] were observed. Majority of the observed syringes were prepared by doctors in paediatric theatres (64.1%, 98/153), and 35.9% (55/153) were prepared by nurses on the wards. Major differences among HCPs in preparation methods were identified. Mean preparation time for morphine syringes was 7.7 minutes (SD ± 3.2). Syringes prepared by doctors in theatres http://www.selleck.co.jp/products/cobimetinib-gdc-0973-rg7420.html had a mean preparation time of 6.4 minutes (SD ± 2.2) compared to those prepared on wards by nurses (10 minutes, SD ± 3.5), p < 0.001. For 59.2% (58/98) of syringes prepared by doctors in theatre compared to 21.2% (12/55) prepared by nurses on wards, the dose calculation was not checked with a second person, (p < 0.001). Confusion of HCPs about the exact content of the morphine ampoule was identified, mainly in theatres (doctors). Final volume prepared was above the required volume (50 mL) in 33.3% (51/153) preparations [doctors 70.

Significant associations between Scl70 and interstitial lung disease (P = 0.004), RNA Pol III and renal crisis (P = 0.002), U1RNP and pulmonary hypertension (P = 0.006) and Th/To

and pulmonary hypertension (P = 0.034) were seen. Trends were observed with an increased frequency of lung disease with Pm/Scl RGFP966 purchase and Th/To and an increased frequency of myositis with Ku. The presence of Scl70, RNA Pol III and U1RNP was associated with significantly reduced survival as compared with patients with ACA. Conclusions:  Scleroderma-specific autoantibodies are associated with clinical phenotype and survival. “
“To assess the prevalence and factors related to rheumatic musculoskeletal disorders (RMSD) in a rural population of south India. The cross-sectional study included all individuals, 15 years and above, in a rural unit of Calicut District in North Kerala. Data were collected using

the validated World Health Organization – International League of Associations for Rheumatology – Community Oriented Program for the Control of Rheumatic Diseases – Bhigwan model questionnaire by trained volunteers. In Phase 1 details of demographic characteristics, major co-morbidities and perceived musculoskeletal aches and pains were elicited. Phases 2 and 3 further evaluated and diagnosed the subjects. Predictors for RMSD were assessed using binary logistic regression analysis. There were 4999 individuals in the study. The prevalence of RMSD was Romidepsin datasheet 24.9%

(95% CI 23.73; 26.12%). Females constituted 50.7% of the population; 5.1% of the respondents were illiterate; 80.9% belonged to low-income groups. Diabetes mellitus and hypertension affected 4.1% and 5.4% of the subjects respectively. The predictors for RMSD in the population were female sex, age, illiteracy, Nintedanib ic50 married status, low-income group, vegetarian diet, current alcohol consumption, current tobacco use, history of injury or accidents, diabetes and hypertension. Symptom-related ill-defined rheumatism (10.39%) followed by osteoarthritis (3.85%) were the most prevalent in the Phase 3 rheumatological evaluation. There is an urgent need to introduce lifestyle modifications in high-risk groups and start rehabilitation for those affected. Community rheumatology in primary health care settings in rural areas needs to be strengthened by introducing national programs addressing RMSD at the grassroots level. “
“In collaboration with the Targeted Ultrasound Initiative (TUI), to conduct the first study in Korea to investigate current practices in ultrasound use among Korean rheumatologists. We translated the TUI Global Survey into Korean and added questions to better understand the specific challenges facing rheumatologists in Korea.

Our data showed that the mioC mutant is defective in both biofilm formation and aggregation, Doxorubicin molecular weight which suggested that the mioC gene may be important for biofilm formation in P. aeruginosa, which is consistent with other reports. Interestingly, biofilm formation of the mioC mutant was boosted under iron depletion and some metal stresses. Fld has been shown to replace bacterial ferredoxin

and this protein can enhance bacterial tolerance to iron starvation (Sancho, 2006). Therefore, the mioC gene mutant may feel stressed under iron depletion so that more biofilms are produced for their survival under this condition. Also, metals are known to induce oxidative stress in bacterial cell and bacterial Fld influences in the defense against oxidative stress (Imlay, 2006; Sancho, 2006). Thus, the mioC mutant is in danger under excess metal conditions and induces

biofilm formation as a defense. It has been shown that motility is important for E. coli and P. aeruginosa biofilm formation (O’Toole & Kolter, 1998; Pratt & Kolter, 1999). Consistent with those data, we demonstrated that motility and biofilm formation were enhanced in the mioC mutant under iron-depleted conditions. Pyocyanin has been reported to function as an electron shuttle for iron acquisition (Hernandez et al., 2004). Natural products such as pyocyanin may promote microbial metal reduction in the environment (Hernandez et al., 2004). In addition, pyocyanin alters the carbon flux of carbon metabolism (Price-Whelan drug discovery et al., 2007). Dichloromethane dehalogenase In this study, we suggested that the mioC mutant strain may be very sensitive to iron limitation, over-producing pyocyanin in response. The mutant cells were also sensitive to metal stresses. Therefore, the mioC mutant cell may

recognize the deficiency of the reduced metal due to depletion of Fld, which functions as an electron donor in bacteria, and therefore produces pyocyanin to acquire metals from the environment. Interestingly, cell death after the stationary phase was accelerated in the mioC mutant cell, whereas there was no difference in exponential growth rate between the cells (wild type, 0.43 ± 0.04; ∆mioC, 0.41 ± 0.03; mioC OE, 0.41 ± 0.05) (Fig. S5). This means that pyocyanin-induced over-production of mutant may be able to promote cell death with redox imbalance, because pyocyanin generates reactive oxygen species that induce oxidative stress in bacteria (Hassan & Fridovich, 1980). It has been proposed that the long-chain Flds may have preceded the shorter ones, such as MioC (Sancho, 2006). Interestingly, Fld is not present in higher eukaryotes and appears fused in multi-domain proteins of eukaryotes. Escherichia coli has some Fld in its genome; however, one Fld (MioC) is annotated in the Pseudomonas species chromosomes (Yeom et al., 2009a). Therefore, Pseudomonas species may be closer from an evolutionary perspective to eukaryotes than E.

Methods The setting was a culturally diverse tri-county (Palm Beach, Broward and Miami Dade counties) area of South Florida. The research design was cross-sectional and descriptive; data were gathered from respondents using a facilitator-administered survey instrument. Key findings The overall reliability of the survey was 0.669 using Cronbach’s α. When EID and PUM survey statements were analysed alone, internal consistency was 0.692 and

0.545 respectively. The association between scores and select demographic variables were analysed and no correlation was found. The previously validated scale (UK) was not reliable in the complex cultural population of Florida. Conclusions Instruments demonstrating reliability in one country are not immediately replicable http://www.selleckchem.com/products/dabrafenib-gsk2118436.html in other countries, even if the same language is spoken. Caution needs to be taken when interpreting the findings this website from studies using instruments designed in cultural contexts dissimilar from those in which the have been developed originally. “
“The aim of this review was to establish type(s) and possible cause(s) of medicine-related problems (MRPs) experienced by ethnic minorities in the UK and to identify recommendations to support these patients in the

effective use of medicines. A systematic search of studies related to problems with medicine use experienced by ethnic minorities in the UK was performed using the following databases: PubMed, Embase, International Pharmaceutical Abstract and Scopus from 1990 to 2011. A hand search for relevant citations and key journals was also performed. Fifteen studies were found. The MRPs identified across studies included lack of information, problems with not taking medicines as advised, concern of dependency or side effects, lack of regular monitoring and review, risk of adverse drug reactions, adverse events and problems in accessing healthcare services. Many problems are common

in other groups, however, studies examining possible explanatory factors discussed how the cultural and religious Cell press beliefs, previous experiences, different expectations, language and communication barriers, lack of knowledge of the healthcare services and underestimating patients’ desire for information may contribute to the problems. Some of the recommendations were made based on the problems that were found, but these have not been evaluated. Little evidence is known of what influences MRPs among ethnic minorities, despite the increased diversification of populations in countries throughout the world. To support their entire populations in the use of medicines, we have to ensure that we understand their different perspectives and needs regarding the effective use of medicines.

Indeed, new viable NCC cysts appeared on the cranial MRI 3 years later despite the fact that he had not traveled in endemic areas during this time. Perhaps this website this patient

could have been a candidate for T solium eradication, which requires adequate treatment of tapeworm carriers with a single dose of niclosamide (2 g) or praziquantel (5 mg/kg).[12] However, it is also possible that he was re-infested in his household as has been reported in some clusters of NCC.[13, 14] As an example, a follow-up of cysticercosis cases reported in Los Angeles in the 1980s demonstrated at least one active tapeworm carrier among family contacts of 22% of locally acquired cases, and 5% of imported cases.[15] According to the CDC, identification and treatment of tapeworm carriers is an important public health measure that can prevent

further cases. Therefore, the CDC recommends that such employees should have stool examinations for taeniasis and be treated if found to be infected.[16] Every physician should be aware of the risk of NCC in immigrants and travelers with neurological symptoms and know that negative serology does not rule out the diagnosis. If the diagnosis of NCC is likely, a presumptive treatment should be started and the serology should be repeated at least 1 week later in order to confirm the diagnosis. The authors wish to thank C. Hirsch, MD, for the editorial work. The authors http://www.selleckchem.com/products/uk-371804-hcl.html state they have no conflicts of interest Protein kinase N1 to declare. “
“Two cases of acute strongyloidiasis occurring in an Italian couple recently returned from a vacation in Thailand are published in this issue.1 The infection was most likely acquired in Koh Samui Island because this was the only place where they walked barefoot on

herbal soil surrounding their bungalow. These cases highlight the growing importance of strongyloidiasis in travelers, especially in light of the potentially serious consequences of the infection. Strongyloidiasis, a soil-transmitted helminth infection that is endemic in tropical and subtropical countries, has recently been considered as an “emerging global infectious disease.”2 Travelers are at risk when they walk barefoot or in sandals in endemic areas, although the risk from beach activities is unknown. Strongyloidiasis includes in its life cycle three successive phases: skin penetration (usually asymptomatic), an acute (or invasive) phase, and chronic infection.3,4 It is noteworthy that strongyloides has the ability to replicate by autoinfection, thereby ensuring that a chronic infection remains for the lifetime of the host. The two cases reported in this issue are characteristic of acute strongyloidiasis, a clinical entity rarely reported in the literature even though it is regularly mentioned in most reviews of the subject.