Activation of human STING by a molecular glue-like compound.

Stimulator of interferon genes (STING) is a dimeric transmembrane adapter protein that plays a key role in the human innate immune response to infection and has been therapeutically exploited for its antitumor activity. The activation of STING requires its high-order oligomerization, which could be induced by binding of the endogenous ligand, cGAMP, to the cytosolic ligand-binding domain. Here we report the discovery through functional screens of a class of compounds, named NVS-STGs, that activate human STING. Our cryo-EM structures show that NVS-STG2 induces the high-order oligomerization of human STING by binding to a pocket between the transmembrane domains of the neighboring STING dimers, effectively acting as a molecular glue. Our functional assays showed that NVS-STG2 could elicit potent STING-mediated immune responses in cells and antitumor activities in animal models.

Author Correction: CPSF3-dependent pre-mRNA processing as a druggable node in AML and Ewing's sarcoma.

An amendment to this paper has been published and can be accessed via a link at the top of the paper.

CPSF3-dependent pre-mRNA processing as a druggable node in AML and Ewing's sarcoma.

The post-genomic era has seen many advances in our understanding of cancer pathways, yet resistance and tumor heterogeneity necessitate multiple approaches to target even monogenic tumors. Here, we combine phenotypic screening with chemical genetics to identify pre-messenger RNA endonuclease cleavage and polyadenylation specificity factor 3 (CPSF3) as the target of JTE-607, a small molecule with previously unknown target. We show that CPSF3 represents a synthetic lethal node in a subset of acute myeloid leukemia (AML) and Ewing's sarcoma cancer cell lines. Inhibition of CPSF3 by JTE-607 alters expression of known downstream effectors in AML and Ewing's sarcoma lines, upregulates apoptosis and causes tumor-selective stasis in mouse xenografts. Mechanistically, it prevents the release of newly synthesized pre-mRNAs, resulting in read-through transcription and the formation of DNA-RNA hybrid R-loop structures. This study implicates pre-mRNA processing, and specifically CPSF3, as a druggable target providing an avenue to therapeutic intervention in cancer.

The Effects of Supplementation with p-Synephrine Alone and in Combination with Caffeine on Metabolic, Lipolytic, and Cardiovascular Responses during Resistance Exercise.

OBJECTIVE: The purpose of this study was to examine the metabolic, lipolytic, and cardiovascular responses to supplementation with p-synephrine alone and in combination with caffeine during resistance exercise (RE). METHODS: Twelve healthy men performed a control RE protocol (6 × 10 repetitions of squats) and were randomly assigned (using a double-blind crossover design with random protocol sequencing) to a supplement sequence: p-synephrine (S; 100 mg), p-synephrine + caffeine (SCF; 100 mg of p-synephrine plus 100 mg of caffeine), or a placebo (P). Subjects reported to the lab at a standard time, consumed a supplement, sat quietly for 45 minutes, performed the RE protocol, and sat quietly for 30 minutes. Blood samples were collected at rest (T1), after sitting quietly for 45 minutes (T2), immediately following RE (T3), and 15 minutes (T4) and 30 minutes (T5) postexercise. Oxygen consumption (VO2) and heart rate (HR) data were collected throughout. RESULTS: Serum glycerol was significantly elevated at T2 only in S and SCF and T3 to T5 in all treatments. Nonesterified fatty acid (NEFA) concentrations did not differ between treatments. Plasma glucose was significantly elevated compared to T1 with highest area under the curve values seen in SCF. Mean VO2 and energy expenditure (EE) were significantly higher in S and SCF through 30 minutes postexercise. Fat oxidation rates favored S and SCF between 25 and 30 minutes postexercise. Mean HR during RE was significantly highest in SCF. CONCLUSIONS: Supplementation with S and SCF increases lipolysis primarily at rest and increases VO2, EE, and fat oxidation rates 30 minutes following RE. No HR changes were observed unless caffeine was added.

Nannocystin†A: an Elongation Factor 1 Inhibitor from Myxobacteria with Differential Anti-Cancer Properties.

Cultivation of myxobacteria of the Nannocystis genus led to the isolation and structure elucidation of a class of novel cyclic lactone inhibitors of elongation factor 1. Whole genome sequence analysis and annotation enabled identification of the putative biosynthetic cluster and synthesis process. In biological assays the compounds displayed anti-fungal and cytotoxic activity. Combined genetic and proteomic approaches identified the eukaryotic translation elongation factor 1α (EF-1α) as the primary target for this compound class. Nannocystin A (1) displayed differential activity across various cancer cell lines and EEF1A1 expression levels appear to be the main differentiating factor. Biochemical and genetic evidence support an overlapping binding site of 1 with the anti-cancer compound didemnin B on EF-1α. This myxobacterial chemotype thus offers an interesting starting point for further investigations of the potential of therapeutics targeting elongation factor 1.

Discovery of potent, selective, bioavailable phosphodiesterase 2 (PDE2) inhibitors active in an osteoarthritis pain model, part I: transformation of selective pyrazolodiazepinone phosphodiesterase 4 (PDE4) inhibitors into selective PDE2 inhibitors.

We identified potent, selective PDE2 inhibitors by optimizing residual PDE2 activity in a series of PDE4 inhibitors, while simultaneously minimizing PDE4 activity. These newly designed PDE2 inhibitors bind to the PDE2 enzyme in a cGMP-like mode in contrast to the cAMP-like binding mode found in PDE4. Structure activity relationship studies coupled with an inhibitor bound crystal structure in the active site of the catalytic domain of PDE2 identified structural features required to minimize PDE4 inhibition while simultaneously maximizing PDE2 inhibition.

Discovery of potent selective bioavailable phosphodiesterase 2 (PDE2) inhibitors active in an osteoarthritis pain model. Part II: optimization studies and demonstration of in vivo efficacy.

Selective phosphodiesterase 2 (PDE2) inhibitors are shown to have efficacy in a rat model of osteoarthritis (OA) pain. We identified potent, selective PDE2 inhibitors by optimizing residual PDE2 activity in a series of phosphodiesterase 4 (PDE4) inhibitors, while minimizing PDE4 inhibitory activity. These newly designed PDE2 inhibitors bind to the PDE2 enzyme in a cGMP-like binding mode orthogonal to the cAMP-like binding mode found in PDE4. Extensive structure activity relationship studies ultimately led to identification of pyrazolodiazepinone, 22, which was >1000-fold selective for PDE2 over recombinant, full length PDEs 1B, 3A, 3B, 4A, 4B, 4C, 7A, 7B, 8A, 8B, 9, 10 and 11. Compound 22 also retained excellent PDE2 selectivity (241-fold to 419-fold) over the remaining recombinant, full length PDEs, 1A, 4D, 5, and 6. Compound 22 exhibited good pharmacokinetic properties and excellent oral bioavailability (F=78%, rat). In an in vivo rat model of OA pain, compound 22 had significant analgesic activity 1 and 3h after a single, 10 mg/kg, subcutaneous dose.

A review of the efficacy and safety of banaba (Lagerstroemia speciosa L.) and corosolic acid.

Banaba (Lagerstroemia speciosa L.) extracts have been used for many years in folk medicine to treat diabetes, with the first published research study being reported in 1940. This review summarizes the current literature regarding banaba and its constituents. The hypoglycemic effects of banaba have been attributed to both corosolic acid as well as ellagitannins. Studies have been conducted in various animal models, human subjects and in vitro systems using water soluble banaba leaf extracts, corosolic acid-standardized extracts, and purified corosolic acid and ellagitannins. Pure corosolic acid has been reported to decrease blood sugar levels within 60 min in human subjects. Corosolic acid also exhibits antihyperlipidemic, antioxidant, antiinflammatory, antifungal, antiviral, antineoplastic and osteoblastic activities. The beneficial effects of banaba and corosolic acid with respect to various aspects of glucose and lipid metabolism appear to involve multiple mechanisms, including enhanced cellular uptake of glucose, impaired hydrolysis of sucrose and starches, decreased gluconeogenesis and the regulation of lipid metabolism. These effects may be mediated by PPAR, MAP K, NF-κB and other signal transduction factors. No adverse effects have been observed or reported in animal studies or controlled human clinical trials. Banaba extract, corosolic acid and other constituents may be beneficial in addressing the symptoms associated with metabolic syndrome, as well as offering other health benefits.

Effects of p-synephrine alone and in combination with selected bioflavonoids on resting metabolism, blood pressure, heart rate and self-reported mood changes.

Bitter orange (Citrus aurantium) extract is widely used in dietary supplements for weight management and sports performance. Its primary protoalkaloid is p-synephrine. Most studies involving bitter orange extract and p-synephrine have used products with multiple ingredients. The current study assessed the thermogenic effects of p-synephrine alone and in conjunction with the flavonoids naringin and hesperidin in a double-blinded, randomized, placebo-controlled protocol with 10 subjects per treatment group. Resting metabolic rates (RMR), blood pressure, heart rates and a self-reported rating scale were determined at baseline and 75 min after oral ingestion of the test products in V-8 juice. A decrease of 30 kcal occurred in the placebo control relative to baseline. The group receiving p-synephrine (50 mg) alone exhibited a 65 kcal increase in RMR as compared to the placebo group. The consumption of 600 mg naringin with 50 mg p-synephrine resulted in a 129 kcal increase in RMR relative to the placebo group. In the group receiving 100 mg hesperidin in addition to the 50 mg p-synephrine plus 600 mg naringin, the RMR increased by 183 kcal, an increase that was statistically significant with respect to the placebo control (p<0.02). However, consuming 1000 mg hesperidin with 50 mg p-synephrine plus 600 mg naringin resulted in a RMR that was only 79 kcal greater than the placebo group. None of the treatment groups exhibited changes in heart rate or blood pressure relative to the control group, nor there were no differences in self-reported ratings of 10 symptoms between the treatment groups and the control group. This unusual finding of a thermogenic combination of ingredients that elevated metabolic rates without corresponding elevations in blood pressure and heart-rates warrants longer term studies to assess its value as a weight control agent.

CYP27A1-dependent anti-melanoma activity of limonoid natural products targets mitochondrial metabolism.

Three limonoid natural products with selective anti-proliferative activity against BRAF(V600E) and NRAS(Q61K)-mutation-dependent melanoma cell lines were identified. Differential transcriptome analysis revealed dependency of compound activity on expression of the mitochondrial cytochrome P450 oxidase CYP27A1, a transcriptional target of melanogenesis-associated transcription factor (MITF). We determined that CYP27A1 activity is necessary for the generation of a reactive metabolite that proceeds to inhibit cellular proliferation. A genome-wide small interfering RNA screen in combination with chemical proteomics experiments revealed gene-drug functional epistasis, suggesting that these compounds target mitochondrial biogenesis and inhibit tumor bioenergetics through a covalent mechanism. Our work suggests a strategy for melanoma-specific targeting by exploiting the expression of MITF target gene CYP27A1 and inhibiting mitochondrial oxidative phosphorylation in BRAF mutant melanomas.

A High Content Screen in Macrophages Identifies Small Molecule Modulators of STING-IRF3 and NFkB Signaling.

We screened a library of bioactive small molecules for activators and inhibitors of innate immune signaling through IRF3 and NFkB pathways with the goals of advancing pathway understanding and discovering probes for immunology research. We used high content screening to measure the translocation from the cytoplasm to nucleus of IRF3 and NFkB in primary human macrophages; these transcription factors play a critical role in the activation of STING and other pro-inflammatory pathways. Our pathway activator screen yielded a diverse set of hits that promoted nuclear translocation of IRF3 and/or NFkB, but the majority of these compounds did not cause activation of downstream pathways. Screening for antagonists of the STING pathway yielded multiple kinase inhibitors, some of which inhibit kinases not previously known to regulate the activity of this pathway. Structure-activity relationships (SARs) and subsequent chemical proteomics experiments suggested that MAPKAPK5 (PRAK) is a kinase that regulates IRF3 translocation in human macrophages. Our work establishes a high content screening approach for measuring pro-inflammatory pathways in human macrophages and identifies novel ways to inhibit such pathways; among the targets of the screen are several molecules that may merit further development as anti-inflammatory drugs.

Continuous infusion of local anesthetic at iliac crest bone-graft sites for postoperative pain relief. A randomized, double-blind study.

BACKGROUND: Autologous bone graft is the so-called gold standard for reconstruction of bone defects and nonunions. The most frequent complication is donor site pain. The iliac crest is a common source for autologous bone graft. The purpose of this study was to determine whether a continuous infusion of 0.5% bupivacaine into the iliac crest harvest site provides pain relief that is superior to the relief provided by systemic narcotic pain medication alone in patients undergoing reconstructive orthopaedic trauma procedures. METHODS: A prospective, double-blind randomized study of patients over eighteen years of age who were undergoing harvesting of iliac crest bone graft was conducted. The patients were randomized to the treatment arm (bupivacaine infusion pump) or the placebo arm. Postoperatively, all study patients received morphine sulfate with use of a patient-controlled analgesia pump. The patients recorded the pain at the donor and recipient sites with use of a scale ranging from 0 to 10. The use of systemic narcotic medication was recorded. Independent-samples t tests were used to assess differences in perceived pain relief between the treatment and control groups at zero, eight, sixteen, twenty-four, thirty-two, forty, and forty-eight hours after surgery. Pain was also assessed at two and six weeks postoperatively. RESULTS: Sixty patients were enrolled. Across all data points, except pain at the recipient site at twenty-four hours, no significant differences in the perception of pain were found between the bupivacaine group and the placebo group. On the average, patients in the treatment group reported more pain than those in the control group. No significant difference was found between the two groups with regard to the amount of narcotic medication used. CONCLUSIONS: No difference in perceived pain was found between the groups. The results of this small, unstratified study indicate that continuous infusion of bupivacaine at iliac crest bone-graft sites during the postoperative period is not an effective pain-control measure in hospitalized patients receiving systemic narcotic medication.

Ternatin and improved synthetic variants kill cancer cells by targeting the elongation factor-1A ternary complex.

Cyclic peptide natural products have evolved to exploit diverse protein targets, many of which control essential cellular processes. Inspired by a series of cyclic peptides with partially elucidated structures, we designed synthetic variants of ternatin, a cytotoxic and anti-adipogenic natural product whose molecular mode of action was unknown. The new ternatin variants are cytotoxic toward cancer cells, with up to 500-fold greater potency than ternatin itself. Using a ternatin photo-affinity probe, we identify the translation elongation factor-1A ternary complex (eEF1A·GTP·aminoacyl-tRNA) as a specific target and demonstrate competitive binding by the unrelated natural products, didemnin and cytotrienin. Mutations in domain III of eEF1A prevent ternatin binding and confer resistance to its cytotoxic effects, implicating the adjacent hydrophobic surface as a functional hot spot for eEF1A modulation. We conclude that the eukaryotic elongation factor-1A and its ternary complex with GTP and aminoacyl-tRNA are common targets for the evolution of cytotoxic natural products.

Absence of furanocoumarins in Advantra Z® (Citrus aurantium, bitter orange) extracts.

Grapefruit (Citrus paradisi) juice is known for its ability to alter drug metabolism through inhibition of the cytochrome P450-3A4 (CYP3A4) system, and result in drug-food interactions that may be life threatening. The primary active ingredients in grapefruit responsible for these effects are the furanocoumarins bergapten, bergamottin, and 6',7'-dihydroxybergamottin (DHB). Bergamottin and DHB appear to be the most important in terms of adverse drug interactions. Furanocoumarins are present in the juices and fruits of other Citrus species including C. aurantium (bitter oranges). Bergapten is the predominant furanocoumarin in bitter orange. Bitter orange extracts are widely used in products associated with weight loss, sports performance, and energy production. Questions have been raised about the potential of bitter orange extracts to cause drug interactions. This study examined the furanocoumarin content of four standardized bitter orange extracts (Advantra Z®) by liquid chromatography-mass spectroscopy. The results indicated that the total furanocoumarin content of each of the four extracts was less than 20 µg/g, amounts insufficient to exert significant effects on the metabolism of susceptible drugs in human subjects at the doses commonly used for these extracts.

A 60day double-blind, placebo-controlled safety study involving Citrus aurantium (bitter orange) extract.

Bitter orange (Citrus aurantium) extract and its primary protoalkaloid p-synephrine are widely consumed in dietary supplements for weight management and sports performance. p-Synephrine is also present in foods derived from a variety of Citrus species. Bitter orange extract is commonly used in combination with multiple herbal ingredients. Most clinical studies conducted on bitter orange extract alone have involved single doses. The purpose of this study was to assess the safety of bitter orange extract (approximately 49mg p-synephrine) alone or in combination with naringin and hesperidin twice daily given to 25 healthy subjects per group for 60days in a double-blinded, placebo-controlled protocol. No significant changes occurred in systolic or diastolic blood pressures, blood chemistries or blood cell counts in control or p-synephrine treated groups. Small, clinically insignificant differences in heart rates were observed between the p-synephrine plus naringin and hesperidin group and the p-synephrine alone as well as the placebo group. No adverse effects were reported in the three groups. Bitter orange extract and p-synephrine appear to be without adverse effects at a dose of up to 98mg daily for 60days based on the parameters measured.

A double-blind, randomized, active-controlled study for post-hemorrhoidectomy pain management with liposome bupivacaine, a novel local analgesic formulation.

This randomized, active-controlled study evaluated the extent and duration of analgesia after administration of liposome bupivacaine (LB), a novel formulation of bupivacaine, compared with bupivacaine HCl given via local infiltration in excisional hemorrhoidectomy. One hundred patients were randomly assigned to receive a single dose of bupivacaine HCl 75 mg (0.25% with 1:200,000 epinephrine) or LB 66, 199, or 266 mg upon completion of hemorrhoidectomy. Postoperative pain intensity was assessed using a numeric rating scale at rest to calculate a cumulative pain score (area under the curve). Cumulative pain scores were significantly lower with LB at each study dose (P < 0.05) compared with bupivacaine HCl 72 hours after surgery. Post hoc analysis showed that mean total postoperative opioid consumption was statistically significantly lower for the LB 266-mg group compared with the bupivacaine HCl group during the 12- to 72-hour postoperative period (P = 0.019). Median time to first opioid use was 19 hours for LB 266 mg versus 8 hours for bupivacaine HCl (P = 0.005). Incidence of opioid-related adverse events was 4 per cent for LB 266 mg compared with 35 per cent for bupivacaine HCl (P = 0.007). Local infiltration with LB resulted in significantly reduced postsurgical pain compared with bupivacaine HCl in patients after hemorrhoidectomy surgery.

A randomized, double-blind, placebo-controlled, multicenter, repeat-dose study of two intravenous acetaminophen dosing regimens for the treatment of pain after abdominal laparoscopic surgery.

BACKGROUND: Intravenous acetaminophen has been approved in Europe and elsewhere for the treatment of acute pain and fever, and was recently approved by the US Food and Drug Administration (FDA) for the management of mild to moderate pain, the management of moderate to severe pain with adjunctive opioid analgesics, and the reduction of fever. OBJECTIVE: The aim of this work was to evaluate the analgesic efficacy and safety of repeated doses of 2 dosing regimens of intravenous acetaminophen compared with placebo over 24 hours in subjects with moderate to severe pain after abdominal laparoscopic surgery. METHODS: This double-blind, placebo-controlled, parallel-group study was conducted at 17 sites in the United States and enrolled adult subjects (aged 18-80 years) who were randomized to 4 groups (IV acetaminophen 1000 mg [100 mL] q6h; IV acetaminophen 650 mg [65 mL] q4h; IV placebo 100 mL q6h; or IV placebo 65 mL q4h), each given as a 15-minute infusion after surgery for 24 hours. An open-label extension was offered to all subjects who remained in the hospital beyond the study period. Two subjects (1 in the placebo 100 mL q6h group and 1 in the IV acetaminophen 1000 mg q6h group) were enrolled in the open-label extension and were eligible to receive unblinded IV acetaminophen 1000 mg. Before randomization, the choice of opioid for patient-controlled analgesia (PCA) rescue was left to the investigator; however, acetaminophen-containing products, NSAIDs, and aspirin were not allowed. The morning after abdominal laparoscopic surgery procedure, subjects' PCA was withheld until pain intensity (PI) was moderate (2) or severe (3) on a categorical scale (range, 0-3) and between 40 and 70 mm, inclusive, on a 100-mm visual analog scale, at which point they were randomized. After the first dose of study medication, intravenous rescue was restricted to morphine or hydromorphone, and oral rescue was restricted to morphine or oxycodone immediate-release tablets. Efficacy analyses were performed using the modified intent-to-treat (mITT) population, defined as all randomized subjects who received ≥ 1 complete dose of study medication before requesting rescue medication, and who had ≥ 1 completed PI/pain relief (PR) assessment after baseline. The primary efficacy end point was the weighted sum of PI differences over 24 hours (SPID24) using an ANCOVA model. Time to meaningful PR was documented after the first dose of study medication using a double-stopwatch method: at T0, 2 stopwatches were started, and subjects were instructed to stop the first stopwatch when they felt perceptible PR and the second when it became meaningful. Safety was assessed via spontaneous adverse event (AE) reporting and laboratory tests. RESULTS: A total of 349 subjects were screened before elective surgery for eligibility. Of these, 244 subjects were randomized to a study arm (IV acetaminophen 1000 mg [n = 92]; IV acetaminophen 650 mg [n = 42]; IV placebo 100 mL [n = 43]; or IV placebo 65 mL [n = 67]) and included in the ITT population, of whom 81.1% (198/244) were women and 87.3% (213/244) were white; the mean (SD) age was 46.2 (12.51) years (range, 18-78 years), and the mean weight was 174.3 (35.7) lb (range, 103-284 lb). There was an allocation error in the contract research organization's program linking group assignment and kit randomization; therefore, the original randomization procedure was replaced with a modified randomization schedule created by an independent biostatistician under the supervision of the FDA. The mITT population included 241 subjects; of these, 227 completed 24 hours of treatment. Four subjects withdrew before completing treatment because of AEs (1 subject in the placebo group because of fever and 3 in the IV acetaminophen 1000 mg q6h group because of infusion-site pain [n = 1] or infiltration [n = 2]), 8 because of withdrawal of consent, 2 because of early discharge from the hospital, and 2 for other reasons. Only 2 subjects participated in the elective open-label extension. Both intravenous acetaminophen dosing regimens were associated with significantly reduced SPID24 compared with placebo (1000 mg q6h, P < 0.007; 650 mg q4h, P < 0.019). Among the mITT population, SPID24 (using nonimputed data after first rescue: 1000 mg q6h, P < 0.001; 650 mg q4h, P = 0.020), sum of PR scores over 24 hours (1000 mg q6h, P < 0.001; 650 mg q4h, P = 0.003) and 12 hours (1000 mg q6h, P < 0.001; 650 mg q4h, P = 0.001), and subjects' global evaluations at 24 hours (1000 mg q6h, P < 0.001; 650 mg q4h, P = 0.005) were statistically significant in favor of both acetaminophen dosing regimens compared with the combined placebo group. Time to meaningful PR (by double stopwatch method) after the first dose was significantly shorter among subjects who received IV acetaminophen 1000 mg compared with subjects in the placebo 100 mL group (median of 24.9 vs 53.9 minutes, respectively). The most common overall AEs (ie, those that occurred in >10% of any group) were constipation, flatulence, nausea, and headache. The frequency of treatment-emergent AEs (TEAEs) across the treatment groups was not statistically significant. Most TEAEs were deemed to be unrelated to study medication. There were 6 subjects with serious TEAEs (1 [0.9%] in the IV acetaminophen 1000 mg group, 3 [7.0%] in the IV acetaminophen 650 mg group, and 2 [1.8%] in the placebo group). There was 1 (2.3%) related hepatic TEAE (transaminase increased) in the placebo group. CONCLUSION: Both regimens of intravenous acetaminophen (1000 mg q6h and 650 mg q4h) were associated with statistically significant analgesic efficacy compared with placebo and were well tolerated in these adults after abdominal laparoscopic surgery. ClinicalTrials.gov identifier: NCT00564486.

Embracing the convenient care concept.

The landscape of primary care medicine is rapidly changing. The decline in interest, both in primary care fields and students choosing these career paths, has left a vacuum in the health care system that must be filled. One of the recent developments has been the birth of "convenient care centers," also known as "retail clinics." This form of health care delivery has mostly been entrepreneurial and based in retail organizations, such as drug stores. These walk-in clinics provide basic medical care for minor common medical conditions, such as sore throat, urinary tract infection, the common cold, and ear infections. Much of this care is provided not by physicians, but by nurse practitioners or physician assistants. After seeing the success of the earliest of these clinics, MinuteClinic by CVS, many other businesses joined the venture, and retail clinics popped up in Wal-Mart, Target, and many local grocery stores. Gradually, hospital systems, physician groups, and managed care companies have also entered the market, sometimes partnering with retail outlets, such as the local grocery store or Wal-Mart, and less often, starting a stand-alone facility. Only 12% of retail clinics are owned by hospital systems or physician groups, while 73% are owned by CVS, Walgreens, or Target. There is even a national nonprofit organization called the Convenient Care Association, started in 2006, and based in Philadelphia, PA. This new trend in delivering health care has been mostly, if not totally, ignored by the medical school practice plans, with the exception of the Mayo Clinic in Minnesota, which has developed several "express care" clinics as stand-alone facilities. As a medical school practice plan and a division of general internal medicine, we could continue to keep a blind eye toward this new trend in primary care medicine or embrace the concept. We aim to develop a new convenient care model integrating our College of Medicine practice plan in partnership with our College of Nursing graduate nursing program to form a stand-alone clinic within a bustling business district in downtown Philadelphia.

Physicochemical space for optimum oral bioavailability: contribution of human intestinal absorption and first-pass elimination.

Oral bioavailability (F) is a product of fraction absorbed (Fa), fraction escaping gut-wall elimination (Fg), and fraction escaping hepatic elimination (Fh). In this study, using a database comprised of Fa, Fg, Fh, and F values for 309 drugs in humans, an analysis of the interrelation of physicochemical properties and the individual parameters was carried out in order to define the physicochemical space for optimum human oral bioavailability. Trend analysis clearly indicated molecular weight (MW), ionization state, lipophilicity, polar descriptors, and free rotatable bonds (RB) influence bioavailability. These trends were due to a combination of effects of the properties on Fa and first-pass elimination (Fg and Fh). Higher MW significantly impacted Fa, while Fg and Fh decreased with increasing lipophilicity. Parabolic trends were observed for bioavailability with polar descriptors. Interestingly, RB has a negative effect on all three parameters, leading to its pronounced effect on bioavailability. In conclusion, physicochemical properties influence bioavailability with typically opposing effects on Fa and first-pass elimination. This analysis may provide a rational judgment on the physicochemical space to optimize oral bioavailability.