Reappraisal of the historical selective pressures for the CCR5-Delta32 mutation

HIV strains are unable to enter macrophages that carry the CCR5-Delta32 deletion; the average frequency of this allele is 10% in European populations. A mathematical model based on the changing demography of Europe from 1000 to 1800 AD demonstrates how plague epidemics, 1347 to 1670, could have provided the selection pressure that raised the frequency of the mutation to the level seen today. It is suggested that the original single mutation appeared over 2500 years ago and that persistent epidemics of a haemorrhagic fever that struck at the early classical civilisations served to force up the frequency to about 5x10(-5) at the time of the Black Death in 1347.

Prevention of early renal disease, dyslipidaemia and lipid peroxidation in STZ-diabetic rats by LR-9 and LR-74, novel AGE inhibitors

BACKGROUND

Increased formation of advanced glycation/lipoxidation endproducts (AGEs/ALEs) has been implicated in the pathogenesis of various diabetic complications. Several compounds have been developed as inhibitors of AGE/ALE formation. We examined the effects of two new AGE/ALE inhibitors, LR-9 and LR-74, on the development of early renal disease and lipid metabolism in streptozotocin (STZ)-induced diabetic rats.

METHODS

Diabetic Sprague-Dawley rats were treated with either of the LR compounds for 32 weeks. Progression of renal disease was evaluated by measurements of urinary albumin and plasma creatinine concentrations. AGE/ALE and nitrotyrosine levels in kidneys were determined by immunohistochemistry. AGE-induced chemical modification of the tail tendon collagen and levels of Nepsilon-(carboxymethyl) and (carboxyethyl)- lysines (CML and CEL) in skin collagen were measured. Plasma lipids and their lipid hydroperoxide concentrations were also determined. In vitro, both compounds were tested for inhibiting lipid peroxidation reactions.

RESULTS

Treatment of either LR compounds significantly inhibited the increase in albuminuria, creatinaemia, hyperlipidaemia and lipid peroxidation in diabetic rats without any effect on hyperglycaemia. Both compounds also reduced CML-AGE and nitrotyrosine accumulation in kidney glomeruli and tubules, AGE-linked fluorescence and cross-linking of tail collagen, and levels of CML and CEL in skin collagen. In vitro, LR compounds inhibited the oxidation of human low-density lipoprotein (LDL).

CONCLUSION

Both compounds can inhibit the progression of renal disease and also prevent dyslipidaemia in type-1 diabetic animals. These compounds may have an additional beneficial effect as an antioxidant against lipid peroxidation, and thus may provide alternative therapeutic options for the treatment of various diabetic macrovascular complications.

Renoprotective and lipid-lowering effects of LR compounds, novel advanced glycation end product inhibitors, in streptozotocin-induced diabetic rats

The accelerated formation of advanced glycation/lipoxidation end products (AGEs/ALEs) has been implicated in the pathogenesis of various diabetic complications. Several natural and synthetic compounds have been proposed and advanced as inhibitors of AGE/ALE formation. We examined the effects of two new AGE/ALE inhibitors, LR-9 and LR-74, on the prevention of early renal disease and dyslipidemia in streptozotocin (STZ)-induced diabetic rats. Diabetic rats were treated with either LR-9 or LR-74 for 32 weeks. Progression of renal disease was evaluated by measurements of urinary albumin and plasma creatinine concentrations. AGE-induced chemical modification of the tail tendon collagen and levels of Nepsilon-(carboxymethyl)- and (carboxyethyl)- lysines (CML and CEL) in skin collagen were measured. AGE/ALE levels in kidneys were determined by immunohistochemistry. Plasma lipids and their lipid hydroperoxide concentrations were also determined. Treatment of either LR-9 or LR-74 significantly inhibited the increase in albuminuria, plasma creatinine, hyperlipidemia, and plasma lipid peroxidation in diabetic rats without any effects on hyperglycemia. Both compounds also reduced CML-AGE accumulation in kidney glomeruli and tubules, AGE-linked fluorescence and cross-linking of tail collagen, and levels of CML and CEL in skin collagen. These results suggest that both LR compounds can inhibit the progression of renal disease and also prevent dyslipidemia in experimental diabetes. These compounds may have an additional beneficial effect as an antioxidant against lipid peroxidation, and thus may provide alternative therapeutic options for the treatment of various diabetic macrovascular complications.

What caused the Black Death?

For the whole of the 20th century it was believed that the Black Death and all the plagues of Europe (1347-1670) were epidemics of bubonic plague. This review presents evidence that this view is incorrect and that the disease was a viral haemorrhagic fever, characterised by a long incubation period of 32 days, which allowed it to be spread widely even with the limited transport of the Middle Ages. It is suggested that haemorrhagic plague emerged from its animal host in Ethiopia and struck repeatedly at European/Asian civilisations, before appearing as the Black Death. The CCR5-Delta32 mutation confers protection against HIV-1 in an average of 10% of the people of European origin today. It is suggested that all the Deltaccr5 alleles originated from a single mutation event that occurred before 1000 BC and the subsequent epidemics of haemorrhagic plague gently forced up its frequency to 5 x 10(-5) at the time of the Black Death. Epidemics of haemorrhagic plague over the next three centuries then steadily raised the frequency in Europe (but not elsewhere) to present day values.

Creating a DIN to tackle drug-related deaths in the community

Brighton and Hove has one of the highest rates of drug-related deaths in the UK. The deceased commonly have had contact with a number of organizations isolated from each other. The aim of this study was to explore aspects of drug addiction in Brighton as the first stage in the creation of a local Drug addiction Intervention Network (DIN) and to make recommendations about improving the effectiveness of medical contacts so that modifiable risk factors could be addressed appropriately and consistently. The coroner's records of the drug-related deaths in 1998 for Brighton and Hove were cross-referenced with computerized records of the Accident & Emergency department of the local hospital and the police station. Of the 36 drug misusers who died during the year, most were male, mean age 34 years. Alcohol was a common comorbid finding. Seventy-eight per cent were known to the A&E department and 62% had been arrested locally during 1997 or 1998. Such retrospective data can only give limited information. We, therefore, performed a prospective survey. It was carried out by the forensic medical examiner (FME) in 1997-1998, interviewing 41 arrestees to give a profile of the criminally involved drug misusers. With the information obtained, the A&E doctors and FMEs were able to review the medical advice given and establish a protocol for the transfer of severely intoxicated arrestees.

Evaluation of a synthetic CArG promoter for nitric oxide synthase gene therapy of cancer

Nitric oxide synthase gene therapy has been shown to be effective at inducing apoptosis in experimental tumours and sensitizing them to radiotherapy. We have also shown that expression of inducible nitric oxide synthase (iNOS) can be effectively restricted to the tumour volume by the use of the radiation inducible promoter (WAF1) to drive the transgene in clinically relevant protocols. A synthetic construct (pE9), incorporating nine radiosensitive CArG elements from the Egr1 promoter, has recently been developed for cancer gene therapy. We have now investigated basal gene expression of transgenes driven by this promoter to assess its suitability for use in iNOS gene therapy protocols in vivo. Transfection of human microvascular endothelial cells (HMEC-1) with pE9iNOS, using a cationic lipid vector, resulted in progressively increasing (<5-fold) levels of iNOS protein expression up to 8 h after transfection. Transfection of an ex vivo rat artery preparation with pE9iNOS caused 83% inhibition of response to the vasoconstrictor phenylephrine (PE). CMViNOS transfection also reduced response to PE, but by only 52%. A single injection of 25 microg of pE9iNOS DNA in a lipid vector into the centre of a murine sarcoma (RIF1) induced iNOS protein expression by four-fold and increased nitrite concentration eight-fold. This caused a 7-day delay in tumour growth and was more effective than the constitutive CMV-driven construct. Our data suggest that generation of NO*, as a result of iNOS overexpression, is capable of further activating the E9 promoter, through a positive feedback loop, yielding stronger and sustained levels of NO*. This pE9iNOS combination may, therefore, be particularly useful in an anticancer gene therapy strategy as its antitumour effect in vivo was clearly superior to that of the strong constitutive promoter, CMV.

Repositioning the patient: the implications of being ‘at risk’

In the modern era of biomedical practice, genetic knowledge has redefined the idea of 'the patient' to include those who are 'at risk' of disease alongside those who are already sick. For such individuals, it is risk itself that constitutes the raison d'être of medical intervention. Using data from interviews with 58 users of a UK cancer genetics service together with data derived from clinical consultations, we consider the way such patients or clients make sense of a cancer genetic risk estimate and how they integrate genetic risk information into their lifeworld. In particular, we note that patient-clients who are 'at risk' tend to see themselves in a liminal position betwixt the healthy and the sick, and that such individuals consequently seek recourse to systems of medical surveillance that can continuously monitor their state of health. Our analysis also revealed the fact that many of those deemed by professionals to be at low risk of inheriting cancer-related mutations subsequently strove to be re-categorised as being at moderate or high risk of an adverse outcome. A number of explanations concerning lay health beliefs, lay 'representations' of health and the nature of the patient-client's lifeworld are examined and assessed in order to account for this apparent paradox.

Deafness to fear in boys with psychopathic tendencies

The processing of the emotional signals of others is fundamental for normal socialization and interaction. Reduced responsiveness to the expressions of sadness and fear has been implicated in the development of psychopathy (Blair, 1995). The current study investigates the ability of boys with psychopathic tendencies to process auditory affect information. Boys with psychopathic tendencies and a comparison group, as defined by the Antisocial Process Screening Device (APSD: Frick & Hare, 2001), were presented with neutral words spoken with intonations conveying happiness, disgust, anger, sadness and fear and were asked to identify the emotion of the speaker based on prosody. The boys with psychopathic tendencies presented with a selective impairment for the recognition of fearful vocal affect. These results are interpreted with reference to amygdala dysfunction and components of the Integrated Emotion Systems model.

Lower phenytoin serum levels in persons switched from brand to generic phenytoin

After generic phenytoin (PHT) was marketed, the authors identified eight adult patients (ages 34 to 49) whose seizures increased enough to require intervention after switching to generic PHT. The mean total PHT concentration on brand (before generic) was 17.7 +/- 5.3 mg/L, decreased to 12.5 +/- 2.7 mg/L with generic, and increased to 17.8 +/- 3.9 mg/L after brand was re-introduced. Brand and generic PHT do not yield equivalent concentrations in some patients and substitution should not be permitted without physician notification.

Meiotic defects in a man with non-obstructive azoospermia: Case report

Infertile men have an increased frequency of aneuploid sperm. We have determined that decreased recombination is associated with the production of aneuploid sperm in humans. The aim of this study was to determine whether some cases of infertility are associated with decreased meiotic recombination. Analysis of the early stages of meiosis was performed in a 33-year-old man with non-obstructive azoospermia. Newly developed immunocytogenetic techniques were used to identify the synaptonemal complex (SC) in various stages of prophase. Antibodies to meiotic proteins identified the SC (SYN1/SCP3), the centromere (CREST) and recombination sites (MLH1). Only 36 meiotic spreads were recovered from the infertile man, compared with hundreds available from controls. One-third of the cells were in zygotene compared with 4% in controls, demonstrating an inability of bivalents to synapse and progress to pachytene. The infertile man had a greatly reduced frequency of recombination, with a mean of only 32.7 MLH1 foci/cell (range 1-60) compared with 46.0 (range 21-62) in control donors. A high proportion of cells (73%) contained at least one autosomal bivalent with zero MLH1 foci, compared with only 4.5% in control donors. Discontinuities in the SC were also more prevalent (68% of cells versus 26% in controls). This is the first demonstration of dramatic pachytene-stage abnormalities in an infertile man using these powerful new immunocytogenetic techniques.

Paying attention to meaning

Several paradigms show that responses to one event compromise responses to a second event for around 500 ms. Such effects are generally attributed to attentional capacity limitations associated with processing information in the first event. In a task in which targets could be distinguished only by their meaning, we varied the semantic relationship between distractors and targets following at different lags. Semantic relatedness alone produced a classic attentional blink. We conclude by discussing how attention theory might best accommodate these new effects.

Abnormal depolarizing patterns in three patients with filarial infection

Several authors have described a particular potential of automated depolarization analysis in detecting malaria infection as part of the routine full blood count (FBC) performed by the Cell-Dyn 4000 analyzer. In these cases, abnormal depolarizing patterns are due to the presence of leukocyte-associated malaria hemozoin, a pigment which depolarizes the laser light. In this report we describe samples from three individual patients who did not have malaria infection but showed abnormal depolarizing events. Further investigation determined that these samples were from patients infected by the nematode Mansonella perstans. The observed depolarizing pattern consisted of a normal depolarizing eosinophil population and in addition an abnormal depolarizing population that showed a close "linear" relationship between "granularity" (90 degrees depolarization) and "lobularity" (90 degrees polarization). This atypical population was smaller than normal leukocytes and thus clearly different from the patterns associated with malaria infection. Abnormal depolarization patterns of M. perstans clearly do not reflect leukocyte-associated malaria hemozoin. It is possible however that the erythrocyte-lysing agent used to facilitate leukocyte analysis by the instrument may have caused microfilaria fragmentation and thus the distinctive "straight-line" features of the abnormal scatter plots

Localized radiation increases morbidity and mortality after TBI-containing autologous stem cell transplantation in patients with lymphoma

The purpose of this study is to assess the relationship between involved field radiation therapy (IFRT) and treatment-related morbidity and mortality in patients receiving high-dose chemotherapy (HDC), total body irradiation (TBI) and autologous peripheral stem cell transplant (PSCT) for Hodgkin's and non-Hodgkin's lymphoma. Between January 1994 and May 2002, 156 patients underwent HDC, TBI and autologous PSCT. Localized external beam radiation therapy was given to 21 patients for consolidation, or to achieve control of symptomatic or active disease prior to or after transplant. Among patients who had IFRT prior to autologous PSCT, five treatment-related deaths were observed, compared to seven deaths in 135 patients who had autologous PSCT without IFRT (P<0.01). Most deaths were attributable to sepsis and multiorgan failure. A higher incidence of pneumonitis was also noted in patients exposed to mediastinal irradiation. No adverse impact on long-term survival could be demonstrated. Involved field radiation prior to TBI is associated with higher treatment-related mortality in lymphoma patients undergoing autologous peripheral stem cell transplant, necessitating careful monitoring.

LR-90 a new advanced glycation endproduct inhibitor prevents progression of diabetic nephropathy in streptozotocin-diabetic rats

AIMS/HYPOTHESIS

Advanced glycation and lipoxidation endproducts have been implicated in the pathogenesis of diabetic complications, including diabetic nephropathy. LR-90, a new advanced glycation endproduct inhibitor, was investigated for its effects on the development of renal disease in diabetic rats.

METHODS

Diabetic animals were randomly allocated into groups receiving LR-90 or vehicle (untreated). Age- and weight-matched non-diabetic rats were studied concurrently. Body weight, plasma glucose, glycated haemoglobin, urinary albumin and creatine excretions were measured serially. Kidney histopathology, AGE accumulation in cells and tissues, protein oxidation, were also examined. In vitro assays were used to assess the possible mechanism of action of LR-90.

RESULTS

LR-90 inhibited the increase in albumin and creatinine concentrations, and concentrations of circulating AGE in diabetic rats without any effect on glycaemic control. LR-90 treated-rats also showed higher body weights than untreated diabetic rats. LR-90 prevented glomerulosclerosis, tubular degeneration and collagen deposition in the kidney. AGE-induced cross-linking and fluorescence of tail collagen were reduced by LR-90 treatment. LR-90 also decreased AGE accumulation in kidney glomeruli and nitrotyrosine deposition in the renal cortex. In vitro, LR-90 was capable of reacting with reactive carbonyl compounds and was a more potent metal chelator than pyridoxamine and aminoguanidine.

CONCLUSION/INTERPRETATION

LR-90 reduces in vivo AGE accumulation, AGE-protein cross-linking and protein oxidation, and could be beneficial in preventing the progression of diabetic nephropathy. The AGE inhibitory and therapeutic effects of LR-90 could be attributed, at least in part, to its ability to react with reactive carbonyl species and/or potent metal chelating activity that inhibits glycoxidative-AGE formation.

A comparison of physician and patient perception of the problems of habitual snoring

Assumptions are often made by doctors about the nature of the impact of uncomplicated snoring. The aim of this study was to provide a comprehensive view of the problems experienced by snoring patients, and to compare these with the perceptions of otolaryngologists. Part 1: 121 snorers and 419 otolaryngologists completed open-ended problems lists; Part 2: 56 snorers and 63 matched controls completed a mood questionnaire and the Golombok Rust Inventory of Marital State (GRIMS.) There was a clear agreement between snorers and otolaryngologists that sleep-related difficulties comprise the most frequent category of problems that may result from snoring. Snorers report a significantly greater number of physical problems and significantly fewer relationship problems than perceived by otolaryngologists. GRIMS scores were similar in patients and controls. Snorers, however, were significantly more depressed. Doctors appear to address snoring from the twin perspectives of damaged relationships and possible sleep apnoea. Their patients are more concerned about disturbing the sleep of others, and are subject to low mood. The snorers' 25 different responses are now being used as the basis for a Snoring Symptom Index.

Spinal anaesthesia: comparison of plain ropivacaine 5 mg ml(-1) with bupivacaine 5 mg ml(-1) for major orthopaedic surgery

BACKGROUND

Ropivacaine provides effective spinal anaesthesia for total hip arthroplasty. This study was designed to compare the efficacy and safety of plain ropivacaine with plain bupivacaine for spinal anaesthesia in patients undergoing total hip arthroplasty.

METHODS

Sixty-six patients, ASA I or II, were randomized to receive an intrathecal injection of one of two local anaesthetic solutions. Group R (n=32) received 3.5 ml of ropivacaine 5 mg ml(-1) (17.5 mg). Group B (n=34) received 3.5 ml of bupivacaine 5 mg ml(-1) (17.5 mg). The onset and duration of sensory block at dermatome level T10, maximum upper and lower spread of sensory block and the onset, intensity and duration of motor block were recorded, as were safety data.

RESULTS

Onset of motor and sensory block was rapid with no significant differences between the two groups. The median time of onset of sensory block at the T10 dermatome was 2 min (range 2-5 min) in Group R and 2 min in Group B (range 2-9 min). The median duration of sensory block at the T10 dermatome was 3.0 h (range 1.5-4.6 h) in Group R and 3.5 h (2.7-5.2 h) in Group B (P<0.0001). The median duration of complete motor block (modified Bromage Scale 3) was significantly shorter in the ropivacaine group compared with the bupivacaine group (2.1 vs 3.9 h, P<0.001).

CONCLUSIONS

Intrathecal administration of either 17.5 mg plain ropivacaine or 17.5 mg plain bupivacaine was well tolerated and an adequate block for total hip arthroplasty was achieved in all patients. A more rapid postoperative recovery of sensory and motor function was seen in Group R compared with Group B.

Whiplash: a biochemical study of muscle injury

Outcome following whiplash injury of the cervical spine is variable, and the pathology of those with prolonged symptoms is uncertain. We undertook a prospective study in 25 patients to identify whether those with prolonged symptoms following whiplash injury exhibit a rise in serum creatine kinase consistent with significant muscle damage at the time of injury. Transient rise in creatine kinase level was seen in only 2 of 25 patients, neither of whom complained of prolonged symptoms. Of the 8 patients who developed chronic symptoms following whiplash injury, none demonstrated a serum creatine kinase rise. Prolonged symptoms following whiplash injury cannot be explained by biochemically measurable muscle damage.