Herpes simplex virus turns off the TAP to evade host immunity

Many viruses have evolved mechanisms to avoid detection by the host immune system. Herpes simplex virus (HSV) expresses an immediate early protein, ICP47, which blocks presentation of viral peptides to MHC class I-restricted cells. The properties of the newly synthesized class I molecules in HSV-infected cells resemble those of cell lines deficient in the transporter associated with antigen processing (TAP) in that class I molecules are retained in the endoplasmic reticulum, and the heavy chain and beta 2-microglobulin subunits dissociate in detergent extracts but the complex can be stabilized by peptides. We show here that ICP47 binds to TAP and prevents peptide translocation into the endoplasmic reticulum.

Biphasic kinetics of peripheral blood T cells after triple combination therapy in HIV-1 infection: a composite of redistribution and proliferation

The origin of CD4+ T cells reappearing in the blood following antiretroviral therapy in human immunodeficiency virus type-1 (HIV-1) infection is still controversial. Here we show, using mathematical modeling, that redistribution of T cells to the blood can explain the striking correlation between the initial CD4+ and CD8+ memory T-cell repopulation and the observation that 3 weeks after the start of treatment memory CD4+ T-cell numbers reach a plateau. The increase in CD4+ T cells following therapy most likely is a composite of initial redistribution, accompanied by a continuous slow repopulation with newly produced naive T cells.

Changes in plasma HIV-1 RNA and CD4+ lymphocyte counts and the risk of progression to AIDS. Veterans Affairs Cooperative Study Group on AIDS

BACKGROUND

Clinical trials of antiretroviral drugs can take years to complete because the outcomes measured are progression to the acquired immunodeficiency syndrome (AIDS) or death. Trials could be accelerated by the use of end points such as changes in CD4+ lymphocyte counts and plasma levels of human immunodeficiency virus type 1 (HIV-1) RNA and beta 2-microglobulin, but there is uncertainty about whether these surrogate measures are valid predictors of disease progression.

METHODS

We analyzed data from the Veterans Affairs Cooperative Study on AIDS, which compared immediate with deferred zidovudine therapy. Patients' plasma levels of HIV-1 RNA and beta 2-microglobulin were measured in stored plasma.

RESULTS

Among the 129 patients in the immediate-treatment group, 34 had disease that progressed to AIDS, as compared with 57 of the 141 patients in the deferred-treatment group (P = 0.03). Progression to AIDS correlated strongly with base-line CD4+ lymphocyte counts (P = 0.001) and plasma levels of HIV-1 RNA (P < 0.001), but not with base-line levels of beta 2-microglobulin (P = 0.14). A decrease of at least 75 percent in the plasma level of HIV-1 RNA over the first six months of zidovudine therapy accounted for 59 percent of the benefit of treatment, defined as the absence of progression to AIDS (95 percent confidence interval, 13 to 112 percent). Plasma beta 2-microglobulin levels and CD4+ lymphocyte counts explained less of the effect of treatment. A 75 percent decrease in the plasma HIV-1 RNA level plus a 10 percent increase in the CD4+ lymphocyte count could explain 79 percent of the treatment effect (95 percent confidence interval, 27 to 145 percent).

CONCLUSIONS

Treatment-induced changes in the plasma HIV-1 RNA level and the CD4+ lymphocyte count, taken together, are valid predictors of the clinical progression of HIV-related disease and can be used to assess the efficacy of zidovudine and possibly other antiretroviral drugs as well.

Guidelines for perioperative care in elective colonic surgery: Enhanced Recovery After Surgery (ERAS®) Society recommendations

BACKGROUND

This review aims to present a consensus for optimal perioperative care in colonic surgery and to provide graded recommendations for items for an evidenced-based enhanced perioperative protocol.

METHODS

Studies were selected with particular attention paid to meta-analyses, randomised controlled trials and large prospective cohorts. For each item of the perioperative treatment pathway, available English-language literature was examined, reviewed and graded. A consensus recommendation was reached after critical appraisal of the literature by the group.

RESULTS

For most of the protocol items, recommendations are based on good-quality trials or meta-analyses of good-quality trials (quality of evidence and recommendations according to the GRADE system).

CONCLUSIONS

Based on the evidence available for each item of the multimodal perioperative-care pathway, the Enhanced Recovery After Surgery (ERAS) Society, International Association for Surgical Metabolism and Nutrition (IASMEN) and European Society for Clinical Nutrition and Metabolism (ESPEN) present a comprehensive evidence-based consensus review of perioperative care for colonic surgery.

Metalloproteinases: role in breast carcinogenesis, invasion and metastasis

The matrix metalloproteinases (MMPs) are a family of zinc-dependent endopeptidases. Their primary function is degradation of proteins in the extracellular matrix. Currently, at least 19 members of this family are known to exist. Based on substrate specificity and domain organization, the MMPs can be loosely divided into four main groups: the interstitial collagenases, gelatinases, stromelysins and membrane-type MMPs. Recent data from model systems suggest that MMPs are involved in breast cancer initiation, invasion and metastasis. Consistent with their role in breast cancer progression, high levels of at least two MMPs (MMP-2 and stromelysin-3) have been found to correlate with poor prognosis in patients with breast cancer. Because MMPs are apparently involved in breast cancer initiation and dissemination, inhibition of these proteinases may be of value both in preventing breast cancer and in blocking metastasis of established tumours

Randomized trial comparing epirubicin, cisplatin, and fluorouracil versus fluorouracil, doxorubicin, and methotrexate in advanced esophagogastric cancer

PURPOSE

We report the results of a prospectively randomized study that compared the combination of epirubicin, cisplatin, and protracted venous infusion fluorouracil (5-FU) (ECF regimen) with the standard combination of 5-FU, doxorubicin, and methotrexate (FAMTX) in previously untreated patients with advanced esophagogastric cancer.

PATIENTS AND METHODS

Two hundred seventy-four patients with adenocarcinoma or undifferentiated carcinoma were randomized and analyzed for survival, tumor response, toxicity, and quality of life (QL).

RESULTS

The overall response rate was 45% (95% confidence interval [CI], 36% to 54%) with ECF and 21% (95% CI, 13% to 29%) with FAMTX (P = .0002). Toxicity was tolerable and there were only three toxic deaths. The FAMTX regimen caused more hematologic toxicity and serious infections, but ECF caused more emesis and alopecia. The median survival duration was 8.9 months with ECF and 5.7 months with FAMTX (P = .0009); at 1 year, 36% (95% CI, 27% to 45%) of ECF and 21% (95% CI, 14% to 29%) of FAMTX patients were alive. The median failure-free survival duration was 7.4 months with ECF and 3.4 months with FAMTX (P = .00006). The global QL scores were better for ECF at 24 weeks, but the remaining QL data showed no differences between either arm of the study. Hospital-based cost analysis on a subset of patients was similar for each arm and translated into an increment cost of $975 per life-year gained.

CONCLUSION

The ECF regimen results in a survival and response advantage, tolerable toxicity, better QL and cost-effectiveness compared with FAMTX chemotherapy. This regimen should now be considered the standard treatment for advanced esophagogastric cancer.

Efficacy of RTS,S/AS02 malaria vaccine against Plasmodium falciparum infection in semi-immune adult men in The Gambia: a randomised trial

BACKGROUND

RTS,S/AS02 is a pre-erythrocytic malaria vaccine based on the circumsporozoite surface protein of Plasmodium falciparum fused to HBsAg, incorporating a new adjuvant (AS02). We did a randomised trial of the efficacy of RTS,S/AS02 against natural P. falciparum infection in semi-immune adult men in The Gambia.

METHODS

306 men aged 18-45 years were randomly assigned three doses of either RTS,S/AS02 or rabies vaccine (control). Volunteers were given sulfadoxine/pyrimethamine 2 weeks before dose 3, and kept under surveillance throughout the malaria transmission season. Blood smears were collected once a week and whenever a volunteer developed symptoms compatible with malaria. The primary endpoint was time to first infection with P. falciparum. Analysis was per protocol.

FINDINGS

250 men (131 in the RTS,S/AS02 group and 119 in the control group) received three doses of vaccine and were followed up for 15 weeks. RTS,S/AS02 was safe and well tolerated. P. falciparum infections occurred significantly earlier in the control group than the RTS,S/AS02 group (Wilcoxon's test p=0.018). Vaccine efficacy, adjusted for confounders, was 34% (95% CI 8.0-53, p=0.014). Protection seemed to wane: estimated efficacy during the first 9 weeks of follow-up was 71% (46-85), but decreased to 0% (-52 to 34) in the last 6 weeks. Vaccination induced strong antibody responses to circumsporozoite protein and strong T-cell responses. Protection was not limited to the NF54 parasite genotype from which the vaccine was derived. 158 men received a fourth dose the next year and were followed up for 9 weeks; during this time, vaccine efficacy was 47% (4-71, p=0.037).

INTERPRETATION

RTS,S/AS02 is safe, immunogenic, and is the first pre-erythrocytic vaccine to show significant protection against natural P. falciparum infection.

Magnetic resonance imaging volumes of the hippocampus and the amygdala in women with borderline personality disorder and early traumatization

BACKGROUND

Based on findings of stress-induced neural disturbances in animals and smaller hippocampal volumes in humans with posttraumatic stress disorder), we hypothesized that patients with borderline personality disorders (BPD), who often are victims of early traumatization, have smaller volumes of the hippocampus and the amygdala. We assumed that volumes of these brain regions are negatively correlated with traumatic experiences and with neuropsychological deficits.

METHODS

We studied 21 female patients with BPD and a similar group of healthy controls. We performed clinical assessments, a modified version of the Childhood Trauma Questionnaire, and magnetic resonance imaging volumetric measurements of the hippocampus, amygdala, temporal lobes, and prosencephalon. Neuropsychological testing included scales on which disturbances in BPD were previously reported.

RESULTS

The patients with BPD had nearly 16% smaller volumes of the hippocampus (P<.001) and 8% smaller volumes of the amygdala (P<.05) than the healthy controls. The results for both hemispheres were nearly identical and were controlled for the volume of the prosencephalon and for head tilts. The volumes of the hippocampus were negatively correlated with the extent and the duration of self-reported early traumatization only when BPD and control subjects were considered together. Levels of neuropsychological functioning were associated with the severity of depression but not with the volumes of the hippocampus.

CONCLUSION

In female patients with BPD, we found reduction of the volumes of the hippocampus (and perhaps of the amygdala), but the association of volume reduction and traumatic experiences remains unclear. Arch Gen Psychiatry. 2000;57:1115-1122.

Sentinel lymph node biopsy in breast cancer: initial experience at Memorial Sloan-Kettering Cancer Center

BACKGROUND

Sentinel node biopsy (SNB) has emerged as a potential alternative to routine axillary dissection in clinically node-negative breast cancer.

STUDY DESIGN

From September 1995 to June 1996 at Memorial Sloan-Kettering Cancer Center, 60 patients with clinically node-negative cancer underwent SNB, which was immediately followed by standard axillary dissection. Both blue dye and radioisotope were used to identify the sentinel node. SNB was compared with standard axillary dissection for its ability to accurately reflect the final pathologic status of the axillary nodes.

RESULTS

The sentinel node was successfully identified by lymphoscintigraphy in 75% (42 of 56), by blue dye in 75% (44 of 59), by isotope in 88% (52 of 59), and by the combination of blue dye and isotope in 93% (55 of 59) of all 59 evaluable patients. Of the 55 patients in this study where sentinel nodes were identified, 20 (36%) were histologically positive. The sentinel node was falsely negative in three patients, yielding an accuracy of 95%. SNB was more accurate for T1 (98%) than for T2-T3 tumors (82%).

CONCLUSIONS

Lymphatic mapping is technically feasible, reliably identifies a sentinel node in most cases, and appears more accurate for T1 tumors than for larger lesions. Blue dye and radioisotope are complementary techniques, and the overall success of the procedure is maximized when the two are used together.

Allopurinol normalizes endothelial dysfunction in type 2 diabetics with mild hypertension

Therapeutic strategies against free radicals have mostly focused on the augmentation of antioxidant defenses (eg, vitamins C and E). A novel approach is to prevent free radical generation by the enzyme system xanthine oxidase. We examined whether the inhibition of xanthine oxidase with allopurinol can improve endothelial function in subjects with type 2 diabetes and coexisting mild hypertension compared with control subjects of a similar age. We examined 23 subjects (11 patients with type 2 diabetes and 12 healthy age-matched control subjects) in 2 parallel groups. The subjects were administered 300 mg allopurinol in a randomized, placebo-controlled study in which both therapies were administered for 1 month. Endothelial function was assessed with bilateral venous occlusion plethysmography, in which the forearm blood flow responses to intra-arterial infusions of endothelium-dependent and -independent vasodilators were measured. Allopurinol significantly increased the mean forearm blood flow response to acetylcholine by 30% (3.16+/-1.21 versus 2.54+/-0.76 mL. 100 mL(-1). min(-1) allopurinol versus placebo; P=0.012, 95% CI 0.14, 1.30) but did not affect the nitroprusside response in patients with type 2 diabetes. There was no significant impact on either endothelium-dependent or -independent vascular responses in age-matched control subjects. Allopurinol improved endothelial function to near-normal levels. Regarding markers of free radical activity, the level of malondialdehyde was significantly reduced (0.30+/-0.04 versus 0. 34+/-0.05 micromol/L for allopurinol versus placebo, P=0.03) in patients with type 2 diabetes but not in control subjects. The xanthine oxidase inhibitor allopurinol improves endothelial dysfunction in patients with type 2 diabetes with mild hypertension but not in matched control subjects. In the former group, allopurinol restored endothelial function to near-normal levels.

Lessons learned from 500 cases of lymphatic mapping for breast cancer

OBJECTIVE

To evaluate the factors affecting the identification and accuracy of the sentinel node in breast cancer in a single institutional experience.

SUMMARY BACKGROUND DATA

Few of the many published feasibility studies of lymphatic mapping for breast cancer have adequate numbers to assess in detail the factors affecting failed and falsely negative mapping procedures.

METHODS

Five hundred consecutive sentinel lymph node biopsies were performed using isosulfan blue dye and technetium-labeled sulfur colloid. A planned conventional axillary dissection was performed in 104 cases.

RESULTS

Sentinel nodes were identified in 458 of 492 (92%) evaluable cases. The mean number of sentinel nodes removed was 2.1. The sentinel node was successfully identified by blue dye in 80% (393/492), by isotope in 85% (419/492), and by the combination of blue dye and isotope in 93% (458/492) of patients. Success in locating the sentinel node was unrelated to tumor size, type, location, or multicentricity; the presence of lymphovascular invasion; histologic or nuclear grade; or a previous surgical biopsy. The false-negative rate of 10.6% (5/47) was calculated using only those 104 cases where a conventional axillary dissection was planned before surgery.

CONCLUSIONS

Sentinel node biopsy in patients with early breast cancer is a safe and effective alternative to routine axillary dissection for patients with negative nodes. Because of a small but definite rate of false-negative results, this procedure is most valuable in patients with a low risk of axillary nodal metastases. Both blue dye and radioisotope should be used to maximize the yield and accuracy of successful localizations.

Randomized trial comparing epirubicin, cisplatin, and fluorouracil versus fluorouracil, doxorubicin, and methotrexate in advanced esophagogastric cancer

PURPOSE

We report the results of a prospectively randomized study that compared the combination of epirubicin, cisplatin, and protracted venous infusion fluorouracil (5-FU) (ECF regimen) with the standard combination of 5-FU, doxorubicin, and methotrexate (FAMTX) in previously untreated patients with advanced esophagogastric cancer.

PATIENTS AND METHODS

Two hundred seventy-four patients with adenocarcinoma or undifferentiated carcinoma were randomized and analyzed for survival, tumor response, toxicity, and quality of life (QL).

RESULTS

The overall response rate was 45% (95% confidence interval [CI], 36% to 54%) with ECF and 21% (95% CI, 13% to 29%) with FAMTX (P = .0002). Toxicity was tolerable and there were only three toxic deaths. The FAMTX regimen caused more hematologic toxicity and serious infections, but ECF caused more emesis and alopecia. The median survival duration was 8.9 months with ECF and 5.7 months with FAMTX (P = .0009); at 1 year, 36% (95% CI, 27% to 45%) of ECF and 21% (95% CI, 14% to 29%) of FAMTX patients were alive. The median failure-free survival duration was 7.4 months with ECF and 3.4 months with FAMTX (P = .00006). The global QL scores were better for ECF at 24 weeks, but the remaining QL data showed no differences between either arm of the study. Hospital-based cost analysis on a subset of patients was similar for each arm and translated into an increment cost of $975 per life-year gained.

CONCLUSION

The ECF regimen results in a survival and response advantage, tolerable toxicity, better QL and cost-effectiveness compared with FAMTX chemotherapy. This regimen should now be considered the standard treatment for advanced esophagogastric cancer.

The peroxisome proliferator-activated receptor delta promotes lipid accumulation in human macrophages

The peroxisome proliferator-activated receptors (PPARs) are a family of fatty acid-activated transcription factors which control lipid homeostasis and cellular differentiation. PPARalpha (NR1C1) controls lipid oxidation and clearance in hepatocytes and PPARgamma (NR1C3) promotes preadipocyte differentiation and lipogenesis. Drugs that activate PPARalpha are effective in lowering plasma levels of lipids and have been used in the management of hyperlipidemia. PPARgamma agonists increase insulin sensitivity and are used in the management of type 2 diabetes. In contrast, there are no marketed drugs that selectively target PPARdelta (NR1C2) and the physiological roles of PPARdelta are unclear. In this report we demonstrate that the expression of PPARdelta is increased during the differentiation of human macrophages in vitro. In addition, a highly selective agonist of PPARdelta (compound F) promotes lipid accumulation in primary human macrophages and in macrophages derived from the human monocytic cell line, THP-1. Compound F increases the expression of genes involved in lipid uptake and storage such as the class A and B scavenger receptors (SRA, CD36) and adipophilin. PPARdelta activation also represses key genes involved in lipid metabolism and efflux, i.e. cholesterol 27-hydroxylase and apolipoprotein E. We have generated THP-1 sublines that overexpress PPARdelta and have confirmed that PPARdelta is a powerful promoter of macrophage lipid accumulation. These data suggest that PPARdelta may play a role in the pathology of diseases associated with lipid-filled macrophages, such as atherosclerosis, arthritis, and neurodegeneration.

The course of anxiety, depression and drinking behaviours after completed detoxification in alcoholics with and without comorbid anxiety and depressive disorders

We studied the associations between comorbid anxiety and depressive disorders in treated alcoholics, the course of current anxiety and depression during the early and late post-detoxification periods, and drinking behaviours after discharge. Lifetime psychiatric comorbidity was assessed in 100 alcoholics using the Composite International Diagnostic Interview (CIDI). Three subgroups defined as group DA (comorbid depressive and anxiety disorders, n = 15), group A (anxiety disorder only, n = 23), and group NO (no comorbid disorder, n = 62) were studied. Beginning 21 +/- 13 days after cessation of drinking, state anxiety (STAI-X1), trait anxiety (STAI-X2) and depression (BDI) were assessed once per week (t1 to t4) and once more 6 months after discharge (t5, n = 68). The severity of psychopathology decreased during the first 4 weeks after detoxification in all subgroups. However, trait anxiety remained at higher levels in both the comorbid subgroups from t1 to t4. In the follow-up sample, 60.5% of the non-comorbid subjects remained abstinent, but only 26.7% of all comorbid patients and only 12.5% of those with comorbid depressive disorder plus severe current trait anxiety or depression at t1. Independent of their comorbidity status, relapsers at t5 had already reported more trait anxiety than abstainers at t1. We conclude that severe trait anxiety persisting after 3 weeks of abstinence, comorbid depressive and/or anxiety disorders, and combinations of these with moderate or severe current anxiety and depressive states represent the greatest risks of relapse and therefore may indicate a treatment need.

The milk-ejection reflex of the rat: an intermittent function not abolished by surgical levels of anaesthesia

Milk ejection (ME) was studied in the lactating rat by the measurement of intramammary pressure, milk yield and behaviour. An intermittent pattern of ME was observed, both in conscious rats and in rats anaesthetized with tribromoethanol, pentobarbitone sodium and ethyl carbamate. Milk ejection was never seen as a reflex response with the onset of the suckling stimulus; the latency to the first ME varied from 10 min in the conscious rat to > 60 min during deep anaesthesia. Thereafter, ME occurred at regular intervals ranging from 3 to 5 min under optimal conditions to > 15 min during less favourable circumstances, though the young were content to suckle continuously for several hours irrespective of whether they obtained milk.

Each ME was associated with an abrupt and uniform rise in intramammary pressure and simulation of the individual ME was obtained by a rapid i.v. injection of 1 mu. oxytocin. The pups reacted immediately to the rise in pressure with a synchronized extensor reaction and a vigorous increase in suckling which lasted for about 10 s. There was, however, no apparent change in the suckling stimulus to account for the release of endogenous oxytocin some 10–20 s prior to these events. Milk ejection was a reflex phenomenon, nonetheless, for the removal of the pups abolished the intermittent release of oxytocin.

The rise in intramammary pressure was associated directly with the ejection of the milk and the pups abruptly increased in weight. Yields of 10–12 g were obtained from both conscious and anaesthetized rats after 18 h of separation from their young. Most of this milk was expressed in the first ten milk ejections.

Mammary distension and the size of the litter were important parameters determining the pattern of ME. The incidence of ME was appreciably lower in unseparated rats whether anaesthetized or not and in separated rats after prolonged suckling or artificial removal of the milk. A similar reduction was encountered when the number of suckling pups was changed from ten to five.

The physiological principles of the ME reflex in the rat are discussed and a theoretical model is presented.

Long-term survival after epirubicin, cisplatin and fluorouracil for gastric cancer: results of a randomized trial

We report the final results of a prospectively randomized study that compared the combination of epirubicin, cisplatin and protracted venous infusion fluorouracil (5-FU) (ECF regimen) with the standard combination of 5-FU, doxorubicin and methotrexate (FAMTX) in previously untreated patients with advanced oesophagogastric cancer. Between 1992 and 1995, 274 patients with adenocarcinoma or undifferentiated carcinoma were randomized from eight oncology centres in the UK and analysed for response and survival. The overall response rate was 46% (95% confidence interval (CI), 37-55%) with ECF, and 21% (95% CI, 13-28%) with FAMTX (P = 0.00003). The median survival was 8.7 months with ECF and 6.1 months with FAMTX (P = 0.0005). The 2-year survival rates were 14% (95% CI, 8-20%) for the ECF arm, and 5% (95% CI, 2-10%) for the FAMTX arm (P = 0.03). Histologically complete surgical resection following chemotherapy was achieved in ten patients in the ECF arm (three pathological complete responses to chemotherapy) and three patients in the FAMTX arm (no pathological complete responses). The ECF regimen resulted in a response and survival advantage compared with FAMTX chemotherapy. The probability of long-term survival following surgical resection of residual disease is increased by this treatment. The high response rates seen with ECF support its use in the neoadjuvant setting.

Intradermal radiocolloid and intraparenchymal blue dye injection optimize sentinel node identification in breast cancer patients

BACKGROUND

Radiotracer and blue dye mapping of sentinel lymph nodes (SLN) have been advocated as accurate methods to stage the clinically negative axilla in breast cancer patients. The technical aspects of SLN biopsy are not fully characterized. In this study we compare the results of intraparenchymal (IP) and intradermal (ID) injection of Tc-99m sulfur colloid, to establish an optimal method for SLN localization.

METHODS

200 consecutive patients had SLN biopsy performed by a single surgeon. Of these, 100 (Group I) had IP injection and 100 (Group II) had ID injection of Tc-99m sulfur colloid. All patients had IP injection of blue dye as well. Endpoints included (1) successful SLN localization by lymphoscintigraphy, (2) successful SLN localization at surgery, and (3) blue dye-isotope concordance (uptake of dye and isotope by the same SLN).

RESULTS

Isotope SLN localization was successful in 78% of Group I and 97% of group II patients (P < .001). When isotope was combined with blue dye, SLN were found in 92% of group I and 100% of Group II (P < .01). In cases where both dye and isotope were found in the axilla, dye mapped the same SLN as radiotracer in 97% of Group I and 95% of Group II patients.

CONCLUSIONS

The dermal and parenchymal lymphatics of the breast drain to the same SLN in most patients. Because ID injection is easier to perform and more effective, this technique may simplify and optimize SLN localization.

Sex Attractant of the Codling Moth: Characterization with Electroantennogram Technique

trans-8, trans-10-Dodecadien-1-ol is a sex attractant of the codling moth, Laspeyresia pomonella. Antennal responses (electroantennograms) to a series of monounsaturated compounds were used in determining the location and configuration of the two double bonds. The synthetic compound is very attractive to male codling moths in the field.

Isotopic Evidence for Neogene Hominid Paleoenvironments in the Kenya Rift Valley

Bipedality, the definitive characteristic of the earliest hominids, has been regarded as an adaptive response to a transition from forested to more-open habitats in East Africa sometime between 12 million and 5 million years ago. Analyses of the stable carbon isotopic composition (delta(13)C) of paleosol carbonate and organic matter from the Tugen Hills succession in Kenya indicate that a heterogeneous environment with a mix of C3 and C4 plants has persisted for the last 15.5 million years. Open grasslands at no time dominated this portion of the rift valley. The observed delta(13)C values offer no evidence for a shift from more-closed C3 environments to C4 grassland habitats. If hominids evolved in East Africa during the Late Miocene, they did so in an ecologically diverse setting.

The effect of patent ductus arteriosus on flow velocity in the anterior cerebral arteries: ductal steal in the premature newborn infant

Marked changes in blood flow velocity in the anterior cerebral arteries, measured by a Doppler technique, have been related to PDA in premature infants. Thus, 55 premature infants of birth weight less than 2,000 gm were studied. Ten developed PDA between days three and ten of life. A sharp decrease in diastolic flow velocity and an increase in pulse amplitude in the ACA was observed with the occurrence of PDA. Return of these values to normal occurred promptly following closure of the lesion. These changes in flow velocity and pulse amplitude in the ACA appear to be determined principally by changes in systemic diastolic pressure which accompany PDA. There was no consistent relationship between the changes in flow velocity and arterial PCO2 values. These data suggest that PDA may be involved in the genesis of ischemic and hemorrhagic cerebral injury in the premature newborn infant. Thus, the decrease in flow velocity appears to represent a "steal" of blood from the cerebral arteries, analogous to other documented steal phenomena observed in older patients. Major fluctuations of blood flow velocity in the ACA, with opening and closure of the PDA, and the increase in amplitude of each pulse with PDA may, in the presence of disturbed autoregulation, cause rupture of the capillaries of the germinal matrix and thus, IVH.

Prognostic importance of survivin in breast cancer

Survivin is a member of the inhibitor of apoptosis (IAP) family, and is also involved in the regulation of cell division. Survivin is widely expressed in foetal tissues and in human cancers, but generally not in normal adult tissue. This study examined the expression of surviving protein in a series of 293 cases of invasive primary breast carcinoma. Survivin immunoreactivity was assessed using two different polyclonal antibodies, and evaluated semiquantitatively according to the percentage of cells demonstrating distinct nuclear and/or diffuse cytoplasmic staining. Overall, 60% of tumours were positive for survivin: 31% demonstrated nuclear staining only, 13% cytoplasmic only, and 16% of tumour cells demonstrated both nuclear and cytoplasmic staining. Statistical analysis revealed that survivin expression was independent of patient's age, tumour size, histological grade, nodal status, and oestrogen receptor status. In multivariate analysis, nuclear survivin expression was a significant independent prognostic indicator of favourable outcome both in relapse-free and overall survival (P<0.001 and P=0.01, respectively). In conclusion, our results show that survivin is frequently overexpressed in primary breast cancer. Nuclear expression is most common and is an independent prognostic indicator of good prognosis.

Lamivudine is effective in suppressing hepatitis B virus DNA in Chinese hepatitis B surface antigen carriers: a placebo-controlled trial

Lamivudine is a novel 2',3'-dideoxy cytosine analogue that has potent inhibitory effects on hepatitis B virus replication in vitro and in vivo. We performed a single-blind, placebo-controlled study to assess its effectiveness and safety in Chinese hepatitis B surface antigen (HBsAg) carriers. Forty-two Chinese HBsAg carriers were randomized to receive placebo (6 patients) or lamivudine orally in dosages of 25 mg, 100 mg, or 300 mg daily (12 patients for each dosage). The drug was given for 4 weeks. The patients were closely monitored clinically, biochemically, and serologically up to 4 weeks after drug treatment. All 36 patients receiving lamivudine had a decrease in hepatitis B virus (HBV) DNA values of >90% (P < .001 compared with placebo). Although 25 mg of lamivudine was slightly less effective than 100 mg (P = .011) and 300 mg (P = .005), it still induced 94% suppression of HBV DNA after the fourth week of therapy. HBV DNA values returned to pretreatment levels within 4 weeks of cessation of therapy. There was no change in the hepatitis B e antigen status or in aminotransferase levels. No serious adverse events were observed. In conclusion, a 4-week course of lamivudine was safe and effective in suppression of HBV DNA in Chinese HBsAg carriers. The suppression was >90% but reversible. Studies with long-term lamivudine administration should be performed to determine if prolonged suppression of HBV DNA can be achieved.

Diabetes UK evidence-based nutrition guidelines for the prevention and management of diabetes

A summary of the latest evidence-based nutrition guidelines for the prevention and management of diabetes is presented. These guidelines are based on existing recommendations last published in 2011, and were formulated by an expert panel of specialist dietitians after a literature review of recent evidence. Recommendations have been made in terms of foods rather than nutrients wherever possible. Guidelines for education and care delivery, prevention of Type 2 diabetes, glycaemic control for Type 1 and Type 2 diabetes, cardiovascular disease risk management, management of diabetes-related complications, other considerations including comorbidities, nutrition support, pregnancy and lactation, eating disorders, micronutrients, food supplements, functional foods, commercial diabetic foods and nutritive and non-nutritive sweeteners are included. The sections on pregnancy and prevention of Type 2 diabetes have been enlarged and the weight management section modified to include considerations of remission of Type 2 diabetes. A section evaluating detailed considerations in ethnic minorities has been included as a new topic. The guidelines were graded using adapted 'GRADE' methodology and, where strong evidence was lacking, grading was not allocated. These 2018 guidelines emphasize a flexible, individualized approach to diabetes management and weight loss and highlight the emerging evidence for remission of Type 2 diabetes. The full guideline document is available at www.diabetes.org.uk/nutrition-guidelines.

Effects of resistance training on regional and total bone mineral density in premenopausal women: a randomized prospective study

This study was designed to assess the effects of 18 months of resistance exercise on regional and total bone mineral density (BMD) and soft tissue lean mass (STL) in premenopausal women aged 28-39 randomly assigned to an exercise or control group. Twenty-two exercise and 34 control subjects completed the 18-month training study. All subjects were previously inactive and untrained women. Initial, 5-, 12- and 18-month assessments were made of total and regional BMD and total and regional STL using dual energy X-ray absorptiometry. All subjects consumed a 500 mg/day elemental calcium supplement throughout the study. Initial Ca intake without supplement averaged 1,023 mg/day in total sample. Serum levels of bone osteocalcin and dietary assessments using 12 randomly assigned days of diet records were also completed. Muscular strength was assessed from both 1 repetition maximum (RM) testing of 10 weightlifting exercises and by peak torque for hip abduction/adduction and knee extension/flexion. Training increased strength by 58.1% based on 1 RM testing and by 33.8% based on isokinetic testing at 18 months versus baseline. BMD increased significantly above baseline at the lumbar spine for the exercise group at 5 months (2.8%), 12 months (2.3%), and 18 months (1.9%) as compared with controls. Femur trochanter BMD increased significantly (p < 0.05) in the exercise group at 12 months (1.8%) and 18 months (2.0%) but not at 5 months (0.7%) as compared with controls. No changes in total BMD, arm BMD, or leg BMD were found. There was a 20% increase in BGP in the exercise group as compared with controls at 5 months and this difference was maintained throughout the study. For STL, significant increases for total, arm, and leg were found at 5, 12, and 18 months for the exercise group versus control ranging from 1-6% over baseline. These results support the use of strength training for increasing STL and muscular strength with smaller but significant regional increases in BMD in the premenopausal population.