Meta-analysis of the outcomes of Trans Rectus Sheath Extra-Peritoneal Procedure (TREPP) for inguinal hernia.

OBJECTIVES: To evaluate the outcomes of Trans Rectus Sheath Extra-Peritoneal Procedure (TREPP) in patients undergoing elective inguinal hernia repair. METHODS: In compliance with PRISMA statement standards, electronic databases were searched to identify all studies reporting the outcomes of TREPP in patients undergoing elective inguinal hernia repair. The outcomes of interest included recurrence, chronic pain, haematoma, and wound infection. Proportion meta-analysis model was constructed to quantify the risk of postoperative complications and direct comparison meta-analysis model was constructed to compare the outcomes of TREPP and other open techniques. Random-effects modelling was applied to calculate pooled outcome data. RESULTS: Seven studies enrolling 1891 patients undergoing TREPP were included. The mean operative time was 26 min (95% CI 15-36). Pooled analyses showed that TREPP was associated with 3.00% (95% CI 1.00-6.00%) risk of recurrence, 3.00% (95% CI 2.00-6.00%) risk of chronic pain, 8.00% (95% CI 0.00-20.00%) risk of haematoma, and 3.00% (95% CI 0.00-6.00%) risk of wound infection. The results remained consistent through subgroup analysis of patients with primary hernias and those with recurrent hernias. Analysis of a limited number of comparative studies showed no difference between TREPP and Lichtenstein technique in terms of recurrence (OR 1.57, P = 0.26) and chronic pain (OR 1.16, P = 0.59). CONCLUSIONS: The best available evidence suggests that TREPP may be a promising technique for elective repair of inguinal hernias as indicated by low risks of recurrence, chronic pain, haematoma, and wound infection. The available evidence is limited to studies from a same country conducted by almost the same research group which may affect generalisability of the findings. Moreover, there is a lack of comparative evidence on outcomes of TREPP versus other techniques highlighting a need for high-quality randomised controlled trials for definite conclusions. Although the available evidence is not adequate for definite conclusions, the results of current study can be used for sample size calculation and power analysis in future trials.

Controlled synthesis of dicalcium phosphate dihydrate (DCPD) from metastable solutions: insights into pathogenic calcification.

Calcium phosphate (CaP) compounds may occur in the body as abnormal pathogenic phases in addition to their normal occurrence as bones and teeth. Dicalcium phosphate dihydrate (DCPD; CaPO4·2H2O), along with other significant CaP phases, have been observed in pathogenic calcifications such as dental calculi, kidney stones and urinary stones. While other studies have shown that polar amino acids can inhibit the growth of CaPs, these studies have mainly focused on hydroxyapatite (HAp; Ca10(PO4)6(OH)2) formation from highly supersaturated solutions, while their effects on DCPD nucleation and growth from metastable solutions have been less thoroughly explored. By further elucidating the mechanisms of DCPD formation and the influence of amino acids on those mechanisms, insights may be gained into ways that amino acids could be used in treatment and prevention of unwanted calcifications. The current study involved seeded growth of DCPD from metastable solutions at constant pH in the presence of neutral, acidic and phosphorylated amino acid side chains. As a comparison, solutions were also seeded with calcium pyrophosphate (CPP; Ca2P2O7), a known calcium phosphate inhibitor. The results show that polar amino acids inhibit DCPD growth; this likely occurs due to electrostatic interactions between amino acid side groups and charged DCPD surfaces. Phosphoserine had the greatest inhibitory ability of the amino acids tested, with an effect equal to that of CPP. Clustering of DCPD crystals giving rise to a "chrysanthemum-like" morphology was noted with glutamic acid. This study concludes that molecules containing an increased number of polar side groups will enhance the inhibition of DCPD seeded growth from metastable solutions.

Preventing iatrogenic air embolism in the intensive care unit.

Air embolism is a potentially fatal consequence of incorrect connection of endotracheal tube cuff inflator devices. Currently, air lines from these devices can be connected to indwelling cannulae without impediment. This possibility can be eliminated with a simple modification of the air line, as described here.

Osmotic drug delivery using swellable-core technology.

Swellable-core technology (SCT) formulations that used osmotic pressure and polymer swelling to deliver drugs to the GI tract in a reliable and reproducible manner were studied. The SCT formulations consisted of a core tablet containing the drug and a water-swellable component, and one or more delivery ports. The in vitro and in vivo performance of two model drugs, tenidap and sildenafil, formulated in four different SCT core configurations: homogeneous-core (single layer), tablet-in-tablet (TNT), bilayer, and trilayer core, were evaluated. In vitro dissolution studies showed that the drug-release rate was relatively independent of the core configuration but the extent of release was somewhat lower for the homogeneous-core formulation, particularly under non-sink conditions. The drug-release rate was slower with increasing coating thickness and decreasing coating permeability, and was relatively independent of the drug loading and the number and size of the delivery ports. The drug-release rates were similar for the two model drugs despite significant differences in their physicochemical properties. Tablet-recovery and pharmacokinetic studies conducted in beagle dogs showed that the in vivo release of drug from SCT formulations was comparable to the in vitro drug release.

Characterization of the calcium biomineral in the radular teeth of Chiton pelliserpentis.

The radula in a group of molluscan invertebrates, the chitons (Polyplacophora), is a ribbon-like apparatus used for feeding and which bears a series of distinctive mineralized teeth called the major lateral teeth. While some chiton species deposit only iron biominerals in these teeth, many others deposit both iron and calcium. In this study, the calcium biomineral in the teeth of one of the latter types of species, the Australian east-coast chiton, Chiton pelliserpentis, has been isolated and examined for the first time. Spectroscopic and crystallographic techniques have identified the biomineral as a carbonate-substituted apatite with significant fluoride substitution also likely. Fourier-transform infrared and laser Raman spectroscopy indicated that the carbonate content was less than that of either bovine tibia cortical bone or human tooth enamel. X-ray diffraction analysis showed the biomineral to be poorly crystalline due to small crystal size and appreciable anionic substitution. The lattice parameters were calculated to be a = 9.382 A and c = 6.883 A, which are suggestive of a fluorapatite material. It is postulated that structural and biochemical differences in the tooth organic matrix of different chiton species will ultimately determine if the teeth become partly calcified or iron mineralized only.

Comparison of three instruments in predicting accidental falls in selected inpatients in a general teaching hospital.

Accidental patient falls are becoming a major cause of concern for hospitalized inpatients. It is well known that patients who fall once during their hospital stay are more likely to fall again and that fall rates tend to be higher in hospitalized elderly individuals. Concerned health care team personnel recognize that many accidental patient falls may be predicted and, thus, prevented. The best tool to predict falls has not been determined yet. The purpose of this study was to compare the abilities of the Morse Fall Scale (MFS), the Functional Reach (FR) test, and the nurses' clinical judgment in predicting those inpatients on a rehabilitation unit and a geriatric medical ward who were most likely to fall. A total of 98 patients were screened in a 3-month period, with each patient undergoing all three instruments the same day. The results showed that the two objective standardized tests (i.e., MFS, FR) were time consuming and often inconvenient and were no better at prediction than the clinical judgments made by the primary nurses.

What are the factors that influence learning in relation to nursing practice?

Although ongoing education is an expectation of all nurses in today's climate of increasing technology and patient acuity, little is known about the attitudes, beliefs, and values of the general staff nurse toward on-the-job learning. The authors detail the factors that influence the learning ability of nurses on general medical-surgical units in a teaching hospital in relation to their nursing practice. Findings of what promotes learning, what interferes with learning, and how learning is integrated into nursing practice are outlined. Implications for the future are discussed.

Evaluating sensory conflict and postural instability. Theories of motion sickness.

Two experiments were carried out to evaluate the sensory conflict and the postural instability theories of motion sickness. The central hypothesis of sensory conflict theory is that motion sickness is caused by conflict between the current pattern of sensory inputs about self-movement and the pattern that is expected on the basis of previous experience. A subsidiary hypothesis is that the degree of motion sickness is proportional to the magnitude of sensory conflict. The central hypothesis of postural instability theory is that motion sickness is caused by loss of postural control. A subsidiary hypothesis is that the degree of motion sickness is proportional to amount of postural instability, which can be manipulated by physical restraint. In both experiments there were two levels of sensory conflict and two levels of postural restraint. Dependent variables were latency of onset and severity of motion sickness. The widespread occurrence of motion sickness in both experiments clearly confirmed the main hypothesis of sensory conflict theory. The results from Experiment 1, that there was significantly more motion sickness in the restrained condition, and from Experiment 2, that there was no significant difference in symptoms between the two restraint conditions, provide no support for the subsidiary hypothesis of postural instability theory. Evidence relating to the subsidiary proposition of sensory conflict theory was inconsistent.

Predicting injection site muscle damage. I: Evaluation of immediate release parenteral formulations in animal models.

PURPOSE: The current animal model generally accepted by the pharmaceutical industry and the FDA for assessment of muscle damage following intramuscular injection (IM) is the rabbit lesion volume model (RbLV). However, this model is resource intensive. The goal of this study was to find a resource sparing alternative to the rabbit lesion model for assessing injection site toleration in IM formulation screening. METHODS: Short term animal model alternatives to RbLV for evaluating IM formulations were examined. In addition to RbLV, myeloperoxidase (MPO), p-nitrophenyl N-acetyl-beta-glucosaminide (NA beta G) and/or plasma creatine phosphokinase (CK) activities were determined in rabbits (Rb) and rats (Rt) after injection of formulations (digoxin, azithromycin and danofloxacin). The edema from these formulations 24 hr after subcutaneous injection into the rat footpad (RFE) was also determined. RESULTS: MPO and NA beta G were not considered very useful as biochemical predictors of muscle damage for these formulations. Histology generally correlated with RbLV values. Compared to saline, RbLV was marked for all formulations within 1-3 days of injection. After day 3, lesions quickly resolved, and no significant differences were found. For these formulations, all CK animal models and RFE were generally predictive of RbLV. A formulation with RtCK > 1000 U/L or RbCK > 3000 U/L, was predicted to be poorly, tolerated. CONCLUSIONS: Due to ease, number of animals, time and intrinsic mechanism, we concluded that for most formulations, 2 and 4 hr RtCK data alone should be reasonably predictive of muscle damage.

Predicting injection site muscle damage. II: Evaluation of extended release parenteral formulations in animal models.

PURPOSE: The goal of this study was to find a resource sparing alternative to the rabbit lesion model (RbLV) for assessing injection site toleration in extended release (ER) intramuscular (IM) formulation screening. METHODS: ER formulations (danofloxacin oily and aqueous suspensions) were evaluated in RbLV, rat and rabbit plasma creatine phosphokinase (CK), and rat foot edema (RFE) models as described in the companion article. RESULTS: None of the short term models could consistently predict acute and chronic effects of the. For example, RFE predicted little muscle damage from aqueous vehicle (0.03 +/- 0.03 g) and 60 mg/ml (0.08 +/- 0.03 g) formulation; while RbLVdays1-3 was marked and greater (p < 0.05) for 60 mg/ml (6.0 +/- 3.1) than vehicle (2.2 +/- 2.9) formulations. Furthermore, RbLVdays 1-3) for vehicle (6.5 +/- 7.5) and 60 mg/ml (4.9 +/- 4.6) danofloxacin oily formulations were worse (p < 0.05) than oil alone (1.4 +/- 2.2); an observation not predicted by CK models, since they apparently reflected only the acute muscle damage of formulation components immediately available to surrounding tissue at the time of injection. CONCLUSIONS: The CK models may be useful to screen those ER formulations with unacceptable acute damage due to immediately available components. However, to evaluate potential delayed effects from ER formulations, the long-term model RbLV was still recommended.

Stingray hickey.

A large number of injuries from stingrays are reported each year in the United States. Usually these injuries are inflicted by the stingray's tail, after the resting stingray is stepped on. The tail has a stinger that can cause puncture wounds with envenomation. We report a case in which an injury from a stingray was due to its bite.

Changes in biologic phenotype of human immunodeficiency virus during treatment of patients with didanosine.

Progression to AIDS in patients harboring human immunodeficiency virus type-1 (HIV-1) isolates expressing a syncytium-inducing (SI) phenotype is faster than in those in whom the virus expresses a non-SI (NSI) phenotype. Zidovudine monotherapy does not appear to alter this outcome. To examine the role of didanosine (ddI) monotherapy in phenotype expression, HIV-1 isolates from 73 patients receiving ddI for up to 72 weeks were analyzed. After 12 weeks, the number of isolates expressing an NSI phenotype was 29% higher than at the start of treatment. Patients receiving high-dose ddI (375 mg twice daily) were significantly more likely to express the NSI phenotype at 12 weeks than patients who received low-dose ddI (100 mg twice daily), even after adjustment for phenotype and CD4 cell count at baseline, suggesting that ddI may be selective against the faster-replicating virus. ddI at 375 mg twice daily significantly increases the probability of an NSI phenotype over the short term in patients with advanced HIV disease.

Primary structure of the V3 region of gp120 from sequential human immunodeficiency virus type 1 isolates obtained from patients from the time of seroconversion.

V3 loop sequences were compared from 5 human immunodeficiency virus type 1 (HIV-1)-infected patients over time. Three patients remained asymptomatic and 2 became symptomatic with large decrease in CD4 cell counts. The patient isolates were previously evaluated for phenotypic and antigenic properties and had different sensitivities to serum neutralization and changes in phenotype. This study showed a number of amino acid changes for the 2 symptomatic patients, each of whom progressed to AIDS during the study. The only amino acid substitution consistently associated with reduced CD4 cell counts, cytopathic effect, and progression to AIDS was Arg at position 11. Specific amino acid changes could not be correlated with increasing serum neutralization resistance or cytotropism changes. Increased loop charge was associated with a switch from macrophage to T cell tropism and a decrease in the number of CD4 cells. The study shows the importance of naturally occurring mutations in the V3 loop in controlling the biologic properties of HIV-1.

Productive in vitro infection of human umbilical vein endothelial cells and three colon carcinoma cell lines with HIV-1.

The objective of this study was to assess the ability of HIV-1 to establish an in vitro infection of primary human umbilical vein endothelial cells (HUVEC). The HUVEC and colon carcinoma cell lines were inoculated with different isolates of HIV-1 (HIV-1SF2, HIV-1Mck and HIV-1LAI) and productive viral infection was assessed by both the detection of p24 core antigen in the culture supernatants and the presence of specific spliced HIV mRNA. The infection which was detected in the inoculated HUVEC and all the colon carcinoma cell lines could not be blocked using an antibody targeted against the CD4 receptor. Furthermore, the HIV-inoculated HUVEC secreted elevated levels of IL-6 and this increase was found to be proportional to the size of the viral inoculum. No changes in the production of IL-1 beta, TNF-alpha, IFN-alpha and IFN-gamma were detected following HIV infection. The colon carcinoma cells, however, did not secrete increased levels of these cytokines following HIV-1 inoculation. These results confirm that non-CD4 expressing cells, such as endothelial cells and certain colon epithelial cells, serve as targets and reservoirs for HIV. Moreover, the production of IL-6 by HIV-infected endothelial cells may be a contributing factor to the aberrant immunoregulation associated with HIV infection in vivo.

Neutralizing antibodies against sequential autologous human immunodeficiency virus type 1 isolates after seroconversion.

The emergence of human immunodeficiency virus type 1 (HIV-1) variants with different sensitivities to serum neutralization and biologic phenotype was studied for 2-5 years after primary HIV-1 infection in 5 subjects. In 3 subjects, the initial virus isolate from seroconversion could be neutralized by autologous serum, but isolates obtained at two subsequent times exhibited reduced sensitivity to serum neutralization, decreased replication in primary macrophages, and increased ability to induce syncytia. Two of these 3 subjects progressed to AIDS and died. Sequential virus isolates from the other 2 subjects showed variability in sensitivity to serum neutralization or biologic features. These patients remained relatively stable in clinical status. Thus, viruses isolated at seroconversion appear to be either non-syncytium-inducing, strong macrophage-tropic, serum neutralization-sensitive phenotypes with stable clinical status or to have escaped neutralization by autologous sera over time, have reduced macrophage tropism and increased syncytia formation, and be associated with disease progression.

Incorporating computer-based learning in a medical school environment.

A systematic multifaceted approach is effective in integrating computer-based learning in a medical school environment. The need to educate medical students in computer use, the growing economic constraints facing many medical schools, and the permeation of computer technology in the medical profession encourage collaboration across academic disciplines and services to meet well identified instructional needs through computer-based learning.

Pseudofolliculitis barbae associated with an unusual hair whorl.

Descriptions of hair direction in the literature have emphasized unusual patterns of the scalp and associated developmental brain defects. We present the case of a white patient with unilateral pseudofolliculitis barbae associated with a hair whorl in the inframandibular region. To our knowledge, this is the first reported case of pseudofolliculitis barbae associated with a hair whorl.

Black and white differences: narrowing the gap in cancer medicine.

Excess mortality is a complex problem involving multiple sub-problems including culture, economics, lifestyle, issues related to cancer biology, and access to medical care among other issues. Consideration has to be given to the multiple influences that lead to this discrepancy in survival related to cancer and the increased incidence of certain tumors. Increased availability of state-of-the-art cancer treatment to the population as a whole will upgrade the level of care by those that participate in clinical trials; the physicians and finally even those patients who are not entered into the trials. Upgrading the access to information about prevention and control of cancer is of equal importance. There are those tumors with possible biological explanations for increases in cancer incidence in the Black population, in particular, multiple myeloma and prostate cancer. There are tumors which are increasing in incidence in this population with no explanation but which must relate to biological factors.