A Review on the Innovative Surgical Suture and Needle Evaluation and Selection Program.

This report describes an innovative suture and needle clinical evaluation program jointly designed by hospital representatives of Consorta, Inc., a healthcare resource management and group purchasing organization, and United States Surgical/Davis & Geck Sutures (USS/D&G), manufacturer of surgical biomaterials. Nineteen Consorta shareholder hospitals enrolled 699 surgeons to participate in Phase I of this nonexperimental observational study of the clinical performance of surgical needles and sutures. Performance characteristics of the sutures and needles produced by USS/D&G, which were evaluated in 3407 surgical procedures, included packaging and ease of opening, needle strength and sharpness, tissue drag, knot security, tensile strength, and clinically acceptable and unacceptable determinations. In these 30-day studies, the surgeons concluded that the needles and sutures were clinically acceptable in 98.1% of the evaluations. 6 e general, cardiothoracic, and orthopedic surgeons, who performed 73.8% of the product evaluations, reported that the suture and needle products were clinically acceptable in 97.2% of the evaluations. More than half (50.1%) of the evaluations involved the POLISORB* braided synthetic sutures, which received a clinically acceptable rating in 98.4% of the evaluation. The next most frequently used sutures were the SOFSILK*, followed by the monofilament nylon suture. SOFSILK* was found to be clinically acceptable in 98.7% of the evaluations, whereas the monofilament nylon was noted to be clinically acceptable in 96.3% of the evaluations. Surgical needles made by USS/D&G had a 97.9% clinical acceptability rating.

An Update on the Innovative Surgical Double-Glove Hole Puncture Indication Systems: Reliability and Performance.

During operative procedures, operating room personnel wear sterile surgical gloves designed to protect them and their patients against transmissible infections. The Food and Drug Administration (FDA) has set compliance policy guides for manufacturers of gloves. The FDA allows surgeons' gloves whose leakage defect rates do not exceed 1.5 acceptable quality level (AQL) to be used in operating rooms. The implications of this policy are potentially enormous to operating room personnel and patients. This unacceptable risk to the personnel and patient could be significantly reduced by the use of sterile double surgical gloves. Because double-gloves are also susceptible to needle puncture, a double-glove hole indication system is urgently needed to immediately detect surgical needle glove punctures. This warning would allow surgeons to remove the double-gloves, wash their hands, and then don a sterile set of double-gloves with an indication system. During the last decade, Regent Medical has devised non-latex and latex double-glove hole puncture indication systems. The purpose of this comprehensive study is to detect the accuracy of the non-latex and latex double-glove hole puncture indication systems using five commonly used sterile surgical needles: the taper point surgical needle, tapercut surgical needle, reverse cutting edge surgical needle, taper cardio point surgical needle, and spatula surgical needle. After subjecting both the non-latex and latex double-glove hole puncture indication systems to surgical needle puncture in each glove fingertip, these double-glove systems were immersed in a sterile basin of saline, after which the double-gloved hands manipulated surgical instruments. Within two minutes, both the non-latex and latex hole puncture indication systems accurately detected needle punctures in all of the surgical gloves, regardless of the dimensions of the surgical needles. In addition, the size of the color change visualized through the translucent outer glove did not correlate with needle diameter. On the basis of this extensive experimental evaluation, both the non-latex and latex double-glove hole puncture indication systems should be used in all operative procedures by all operating room personnel.

Chemotherapeutic efficacy of phosphodiesterase inhibitors in chagasic cardiomyopathy.

BACKGROUND: Chagasic cardiomyopathy (CCM) caused by Trypanosoma cruzi (Tc) infection is prevalent in Latin America and recognized as an emerging infectious heart disease in the US. The NO-cGMP-PKG1α pathway maintains cardiac homeostasis and inotropy and may be disturbed due to phosphodiesterase (PDE5) mediated cGMP catabolism in CCM. METHODS AND RESULTS: C57BL/6 mice were infected with Tc, and at the end of acute parasitemia (i.e. 45 days post-infection), treated with sildenafil (SIL, 1 mg/kg) twice per week for 3 weeks. Mice were monitored at 150 days post-infection corresponding to chronic disease phase. The cGMP/PKG activity was decreased by 2-fold and PDE5 expression was increased by 1.4-fold and 100% at RNA and protein levels, respectively, in chagasic myocardium. Transthoracic echocardiography showed the left ventricular (LV) systolic function, i.e., stroke volume, cardiac output, and ejection fraction, were significantly decreased in chagasic mice. Sildenafil treatment resulted in normal levels of PDE5 and cGMP/PKG activity and preserved the LV function in chagasic mice. The cardioprotective effects of SIL were provided through inhibition of cardiac collagenosis and chronic inflammation that otherwise were pronounced in CCM. Further, mtDNA-encoded gene expression and ADP-coupled mitochondrial respiration were decreased and mitochondrial oxidative stress and cellular oxidative damage (lipid hydroperoxides and protein carbonyls) were increased in chagasic myocardium. SIL treatment restored the mtDNA-encoded gene expression and complex I (but not complex II) dependent ADP-coupled respiration, and established the oxidant/antioxidant balance in chagasic myocardium. In vitro studies in cardiomyocytes verified that SIL conserved the redox metabolic state and cellular health via maintaining the antioxidant status that otherwise was compromised in response to Tc infection. CONCLUSION: SIL therapy was useful in controlling the LV dysfunction and chronic pathology in CCM.

Homologous recombination proteins are associated with centrosomes and are required for mitotic stability.

In response to DNA damage, cells need robust repair mechanisms to complete the cell cycle successfully. Severe forms of DNA damage are repaired by homologous recombination (HR), in which the XRCC2 protein plays a vital role. Cells deficient in XRCC2 also show disruption of the centrosome, a key component of the mitotic apparatus. We find that this centrosome disruption is dynamic and when it occurs during mitosis it is linked directly to the onset of mitotic catastrophe in a significant fraction of the XRCC2-deficient cells. However, we also show for the first time that XRCC2 and other HR proteins, including the key recombinase RAD51, co-localize with the centrosome. Co-localization is maintained throughout the cell cycle, except when cells are finishing mitosis when RAD51 accumulates in the midbody between the separating cells. Taken together, these data suggest a tight functional linkage between the centrosome and HR proteins, potentially to coordinate the deployment of a DNA damage response at vulnerable phases of the cell cycle.

Revolutionary advances in enhancing patient comfort on patients transported on a backboard.

BACKGROUND: Patients with suspected spinal cord injuries are immobilized to a backboard during ambulance and helicopter air transport. It has been well documented that patients who are immobilized to a backboard experience discomfort and eventually become susceptible to pressure ulcer formation. Because the patient lying on a backboard is subjected to high skin interface pressures, it is imperative to improve patient comfort and prevent pressure ulcer formation. OBJECTIVE: Realizing the dangers of the potentially preventable pressure ulcers, our team of scientists, surgeons, and trauma nurses performed a comprehensive study of the Back Raft system that was designed to reduce patient discomfort and skin interface pressure. METHODS: Pressure under the occipital, scapula, and sacral regions of the back was measured using the Tactilus pressure analyzer of 10 healthy volunteers immobilized on a backboard and a backboard with a Back Raft air mattress system. Discomfort levels of each volunteer were measured using a Visual Analog Scale. RESULTS: Data from this study indicated that the Back Raft significantly reduces discomfort as well as tissue interface pressure in the occipital, scapula, and sacral regions of the back. CONCLUSIONS: The implementation of an air mattress system analogous to the Back Raft would facilitate the prevention of pressure ulcer formation during prehospital care and transportation. In 2008, The Centers for Medicare and Medicaid Services enacted a policy in which the Centers for Medicare and Medicaid Services can refuse payment for hospital-acquired conditions. Pressure ulcers were among the hospital-acquired conditions within the final rule.

Xrcc2 modulates spontaneous and radiation-induced tumorigenesis in Apcmin/+ mice.

XRCC2 has an important role in repair of DNA damage by homologous recombination. Adult Apc(min/+) (min, multiple intestinal neoplasia) mice, wild-type or heterozygous for Xrcc2 deficiency, were sham-irradiated or 2-Gy X-irradiated. Spontaneous mammary and intestinal tumor incidences are lower in Apc(min/+) Xrcc2(+/-) mice than in Apc(min/+) Xrcc2(+/+) mice (mammary tumors: 14% and 38%, respectively, χ(2) P = 0.03; intestinal adenomas in mice reaching full life span: 108.6 and 130.1, respectively, t-test P = 0.005). Following irradiation, the increase in mammary tumors was greatest in female mice heterozygous for Xrcc2 (7.25 ± 0.50-fold in Apc(min/+) Xrcc2(+/-) mice compared with 2.57 ± 0.35-fold in Apc(min/+) Xrcc2(+/+) mice; t-test P < 0.001). The increase in intestinal tumor multiplicity following irradiation was significantly greater in Apc(min/+) Xrcc2(+/-) mice (Apc(min/+) Xrcc2(+/-), 4.14 ± 0.05-fold, versus Apc(min/+) Xrcc2(+/+), 3.30 ± 0.05-fold; t-test P < 0.001). Loss of heterozygosity of all chromosome 18 markers was greater in intestinal tumors from Apc(min/+) Xrcc2(+/-) mice than in tumors from Apc(min/+) Xrcc2(+/+) mice. These findings indicate that Xrcc2 haploinsufficiency reduces spontaneous tumor incidence on an Apc(min/+) background but increases the tumorigenic response to radiation.

The importance of XRCC2 in RAD51-related DNA damage repair.

The repair of DNA damage by homologous recombination (HR) is a key pathway for the maintenance of genetic stability in mammalian cells, especially during and following DNA replication. The central HR protein is RAD51, which ensures high fidelity DNA repair by facilitating strand exchange between damaged and undamaged homologous DNA segments. Several RAD51-like proteins, including XRCC2, appear to help with this process, but their roles are not well understood. Here we show that XRCC2 is highly conserved and that most substantial truncations of the protein destroy its ability to function. XRCC2 and its partner protein RAD51L3 are found to interact with RAD51 in the 2-hybrid system, and XRCC2 is shown to be important but not essential for the accumulation of RAD51 at the sites of DNA damage. We visualize the localization of XRCC2 protein at the same sites of DNA damage for the first time using specialized irradiation conditions. Our data indicate that an important function of XRCC2 is to enhance the activity of RAD51, so that the loss of XRCC2 results in a severe delay in the early response of RAD51 to DNA damage.

Reducing accidental injuries during surgery.

All surgical healthcare professionals and their patients should be aware of exposure to blood from individuals infected with potentially transmissible disease. The site that was most susceptible to sharp injuries was the index finger of the surgeon's hand. It is also important to note that needles cause the vast majority of sharp injuries. During the last two decades, there have been two revolutionary advances in preventing accidental needlestick injuries during surgery that include the development of blunt tapering point needles as well as the double-glove hole indication systems. During the innovative development of blunt taper point needles, a glove manufacturer, Molnlycke, Inc., devised non-latex and latex double-glove hole puncture indication systems that are being used throughout the world. The reliability of these double-glove hole indication systems in detecting holes in the outer glove has been reliably documented by scientific studies that are published in peer-reviewed journals. On the basis of these extensive quantitative studies, the authors recommended that the double-glove hole indication system be used in all operative procedures to prevent the transmission of deadly bloodborne viral infections.

Revolutionary advances in the management of traumatic wounds in the emergency department during the last 40 years: part I.

BACKGROUND AND OBJECTIVES: This report provides an overview of advances in wound repair devised by our research team during the last four decades. This collective review is presented in two parts. DISCUSSION: The following components are included in Part I: 1) search and treat life-threatening trauma; 2) conduct a thorough history; 3) examine the wound using aseptic technique; 4) anesthetize the wound before cleansing; 5) hair removal, skin disinfection, hemostasis, surgical debridement, and mechanical cleansing; 6) antibiotics, drains, and open wound management. CONCLUSION: On the basis of these comprehensive research studies, we have noted a marked reduction in the incidence of wound infection in traumatic wounds.

Revolutionary advances in the management of traumatic wounds in the emergency department during the last 40 years: part II.

BACKGROUND AND OBJECTIVES: During the last four decades, our research team has devised advances in wound repair that are highlighted in Part II of this collective review. DISCUSSION: There are several different methods to provide an accurate and secure approximation of the skin edges-sutures, tapes, staples, and tissue adhesives. Ideally, the selection of the wound closure technique will be based on the biologic interaction of the materials employed, tissue configuration, and biomechanical properties of the trauma wound. Selection of the appropriate wound dressing is another important consideration in the management of the trauma wound. CONCLUSION: On the basis of the comprehensive research and clinical studies, we have individualized the wound closure techniques for traumatic wounds so that healing can be achieved with more aesthetically pleasing scars.

Dangers of cornstarch powder on medical gloves: seeking a solution.

This article reviews information on the hazards of cornstarch powder on medical gloves. Dusting powders were first applied to latex gloves to facilitate donning. After 1980, manufacturers devised innovative techniques without dusting powder. It has been well documented that these powders on gloves present a health hazard to patients and health care workers by 5 different mechanisms. First, the glove cornstarch has documented detrimental effects on wound closure techniques. Second, this powder potentiates wound infection. Third, cornstarch induces peritoneal adhesion formation and granulomatous peritonitis. Finally, these powders serve as carriers as latex allergen and they precipitate a life-threatening allergic reaction in sensitized patients. These well-documented hazards of glove powder have caused the United Kingdom and Germany to ban cornstarch powder on medical gloves over 10 years ago.

Citizen's Petition to Food and Drug Administration to ban cornstarch powder on medical gloves: Maltese cross birefringence.

BACKGROUND: During the last 25 years, scientific experimental and clinical studies have documented the dangers of cornstarch powder on examination and surgical gloves because the cornstarch promotes wound infection, causes serious peritoneal adhesions and granulomatous peritonitis, and is a well-documented vector of the latex allergy epidemic in the world. Realizing the dangers of cornstarch on examination and surgical gloves, Germany's regulations of personal protective equipment banned the use of surgical glove powder cornstarch in 1997. In 2000, the Purchasing and Supply agency for the United Kingdom ceased to purchase any gloves lubricated with cornstarch. DISCUSSION: Realizing the dangers of cornstarch-powdered gloves, many hospitals and clinics in the United States have banned the use of cornstarch-powdered examination and surgical gloves. Hospitals that have banned cornstarch in their examination and surgical gloves have noted a marked reduction in the latex allergy epidemic in their facilities. Realizing the dangers of cornstarch-powdered examination and surgical gloves, Dr Sheila A. Murphey, branch chief, Infection Control Devices Branch, Division of Anesthesiology, General Hospital, Infection Control, and Dental Devices Office of Device Evaluation, Center for Devices and Radiological Health of the Food and Drug Administration (FDA), recommended that a Citizen's Petition be filed to the FDA to ban cornstarch on surgical and examination gloves. CONCLUSION: The 12 authors of this report have attached the enclosed petition to the FDA to ban the use of cornstarch on all synthetic and latex examination and surgical gloves used in the United States.

Homologous recombination repair protects against particulate chromate-induced chromosome instability in Chinese hamster cells.

Particulate hexavalent chromium [Cr(VI)] compounds are well-established human carcinogens. Cr(VI)-induced tumors are characterized by chromosomal instability (CIN); however, the mechanisms of this effect are unknown. We investigated the hypothesis that homologous recombination (HR) repair of DNA double-strand breaks protect cells from Cr(VI)-induced CIN by focusing on the XRCC3 and RAD51C genes, which play an important role in cellular resistance to DNA double-strand breaks. We used Chinese hamster cells defective in each HR gene (irs3 for RAD51C and irs1SF for XRCC3) and compared with their wildtype parental and cDNA-complemented controls. We found that the intracellular Cr ion levels varied among the cell lines after particulate chromate treatment. Importantly, accounting for differences in Cr ion levels, we discovered that XRCC3 and RAD51C cells treated with lead chromate had increased cytotoxicity and chromosomal aberrations, relative to wildtype and cDNA-complimented cells. We also observed the emergence of high levels of chromatid exchanges in the two mutant cell lines. For example, 1microg/cm(2) lead chromate induced 20 and 32 exchanges in XRCC3- and RAD51C-deficient cells, respectively, whereas no exchanges were detected in the wildtype and cDNA-complemented cells. These observations suggest that HR protects cells from Cr(VI)-induced CIN, consistent with the ability of particulate Cr(VI) to induce double-strand breaks.

A role for Xrcc2 in the early stages of mouse development.

Xrcc2 is one of a family of five Rad51-like genes with important roles in the repair of DNA damage by homologous recombination (HR) in mammals. We have shown previously that loss of Xrcc2 in mice results in severe but variable developmental defects and embryonic lethality, potentially linked to excessive apoptosis. To look at the causes of lethality, and possibly to allow Xrcc2-/- mice to survive to birth, we have produced double knockout mice deficient in either the p53 oncoprotein or Ataxia telangiectasia mutated (Atm). Overall we show that the excessive apoptosis observed in Xrcc2-/- embryos is p53-dependent, and that loss of p53 can restore growth capacity to Xrcc2-/- fibroblasts in culture, but that it cannot rescue the embryonic lethality. Additionally, although the Xrcc2-/- Trp53-/- embryos show a near-normal morphology they remain relatively small in size. Loss of Atm in an Xrcc2-/- embryo has little effect, suggesting that response to loss of HR capacity is not mediated through the Atm kinase in the early stages of mouse development. Further, as seen by reduced expression of the early developmental marker, Delta-like1, the normal developmental programme is perturbed in Xrcc2-/- embryonic tissues, particularly during neurogenesis and somitogenesis. Taken together our data suggest that the accumulation of spontaneous damage in HR-deficient embryos has severe consequences for the development and survival of mammals due to the unregulated loss of cells important to the developmental programme.

The roles of specific glycosylases in determining the mutagenic consequences of clustered DNA base damage.

The potential for genetic change arising from specific single types of DNA lesion has been thoroughly explored, but much less is known about the mutagenic effects of DNA lesions present in clustered damage sites. Localized clustering of damage is a hallmark of certain DNA-damaging agents, particularly ionizing radiation. We have investigated the potential of a non-mutagenic DNA base lesion, 5,6-dihydrothymine (DHT), to influence the mutagenicity of 8-oxo-7,8-dihydroguanine (8-oxoG) when the two lesions are closely opposed. Using a bacterial plasmid-based assay we present the first report of a significantly higher mutation frequency for the clustered DHT and 8-oxoG lesions than for single 8-oxoG in wild-type and in glycosylase-deficient strains. We propose that endonuclease III has an important role in the initial stages of processing DHT/8-oxoG clusters, removing DHT to give an intermediate with an abasic site or single-strand break opposing 8-oxoG. We suggest that this mutagenic intermediate is common to several different combinations of base lesions forming clustered DNA damage sites. The MutY glycosylase, acting post-replication, is most important for reducing mutation formation. Recovered plasmids commonly gave rise to both wild-type and mutant progeny, suggesting that there is differential replication of the two DNA strands carrying specific forms of base damage.

Xrcc2 deficiency sensitizes cells to apoptosis by MNNG and the alkylating anticancer drugs temozolomide, fotemustine and mafosfamide.

DNA double-strand breaks (DSBs) are potent killing lesions, and inefficient repair of DSBs does not only lead to cell death but also to genomic instability and tumorigenesis. DSBs are repaired by non-homologous end-joining and homologous recombination (HR). A key player in HR is Xrcc2, a Rad51-like protein. Cells deficient in Xrcc2 are hypersensitive to X-rays and mitomycin C and display increased chromosomal aberration frequencies. In order to elucidate the role of Xrcc2 in resistance to anticancer drugs, we compared Xrcc2 knockout (Xrcc2-/-) mouse embryonic fibroblasts with the corresponding isogenic wild-type and Xrcc2 complemented knockout cells. We show that Xrcc2-/- cells are hypersensitive to the killing effect of the simple methylating agent N-methyl-N'-nitro-N-nitrosoguanidine (MNNG). They undergo apoptosis after MNNG treatment while necrosis is only marginally enhanced. Complementation of Xrcc2 deficient cells by Xrcc2 cDNA transfection conferred resistance to the cytotoxic and apoptosis-inducing effect of MNNG. The hypersensitivity of Xrcc2-/- cells to MNNG prompted us to investigate their killing and apoptotic response to various methylating, chloroethylating and crosslinking drugs used in anticancer therapy. Xrcc2 deficient cells were found to be hypersensitive to temozolomide, fotemustine and mafosfamide. They were also hypersensitive to cisplatin but not to taxol. The data reveal that Xrcc2 plays a role in the protection against a wide range of anticancer drugs and, therefore, suggest Xrcc2 to be a determinant of anticancer drug resistance. They also indicate that HR is involved in the processing of DNA damage induced by simple alkylating agents.

The involvement of key DNA repair pathways in the formation of chromosome rearrangements in embryonic stem cells.

It is vital that embryonic stem (ES) cells, which give rise to the diverse tissues of the mature organism, maintain genetic stability. To understand mechanisms for the prevention and causation of chromosomal instability, we have used spectral karyotyping (SKY) to analyse ES cells from wild-type and repair-gene knockout mice. We chose cells deficient in Ku70 (DNA end joining), Xrcc2 (gene conversion), Ercc1 (single-strand annealing) and Csb (transcription-coupled repair) to represent potentially-important DNA repair pathways, plus an Xpc-deficient line to examine loss of global nucleotide excision repair (NER). Spontaneous and radiation (X-ray or alpha-particle)-induced chromosome changes were assessed to measure the influence of different levels of damage severity on response. We show that most repair pathways (except for global NER) protect against chromosome changes induced by ionizing radiations, while only homology-dependent pathways protect against spontaneous chromosomal change in ES cells. However, for a given level of damage, the prevalence of different types of changes alters in the different repair-deficient lines. Thus, loss of Ercc1, Csb or Ku70 leads to increased fragment formation, but loss of Xrcc2 promotes exchanges between chromosomes. Strikingly, we found that loss of the Csb gene function specifically protects ES cells from complex exchanges, suggesting a role for transcription-associated events in complex exchange formation.