bluuebunny/crossref_metadata_2025 huggingface dataset:
High prevalence of hepatitis B, C, and E markers in young sexually active adults from The Central African Republic
Authors: Pawlotsky Jean‐Michel , Bélec Laurent , Grésenguet Gérard , Deforges Lionel , Bouvier Magali , Duval Jean , Dhumeaux Daniel
Published: March 2007

The Central African Republic is located in tropical Africa, where both the human immunodeficiency virus (HIV) and hepatitis B virus (HBV) are highly endemic. The exact prevalence of hepatitis C virus (HCV) and hepatitis E virus (HEVI markers in this country is unknown. The aim of the study was to determine, according to HlV and HBV serostatus, the prevalence of these markers in young sexually active adults in the Central African Republic. One hundred and fifty‐seven consecutive patients attending the National Centre for Sexually Transmitted Diseases in Bangui were included. The following serological markers were examined: (i) anti‐HIV1 and anti‐HIV2 antibodies; (ii) markers of HBV infection; (iii) anti‐HCV antibodies; (iv) anti‐HEV antibodies. Anti‐HIV1 antibodies were found in 31 of the 157 patients (20%). The prevalence of anti‐HBc antibodies, reflecting exposure to HBV, was 140/157 (89%) and 45 had detectable anti‐HBs antibodies. Twenty‐two patients (14%) were chronic carriers of hepatitis B surface antigen (HBsAg), but only one was HBe antigen‐positive. Anti‐HCV antibodies were found in 8 persons (5%) and antiHEV antibodies in 38 (24%). No difference was found in the prevalence of these markers according to the presence or absence of anti‐HIV antibodies. This study confirms the high rate of HIV infection, HBV exposure and chronic carriage of HBsAg in sexually active young adults in the Central African Republic. A high prevalence of HCV markers was found in this population, similar to that reported in neighbouring countries, together with a high rate of HEV markers, suggesting that HEV is endemic in this region. © 1995 Wiley‐Liss, Inc.
Genotype distribution and comparison of the putative envelope region of hepatitis C virus from Korean patients
Authors: Kim Chul‐Joong , Shin Kwangsoon , Kim Won‐Yong , Lim Dong‐Soo , Yoon Seung‐Kew , Park Youngmin , Kim Boo‐Sung , Jang Sung‐Key , Cho Myung‐Je
Published: March 2007

Comparative nucleotide sequence studies of the genomes of hepatitis C virus (HCV) revealed that there are at least 6 different genotypes of HCV. The prevalence of HCV genotypes among the patients with liver diseases in Korea was investigated using the polymerase chain reaction (PCR) for the NS5 region. In the 75 HCV RNA positive samples, two genotypes, type 1b and type 2a, were the major causative agents which accounted for 60% and 33% of infections respectively, while 7% could not be assigned a genotype by the methods used. The nucleotide sequences of cDNAs encoding the putative envelope proteins from 10 type 1b and 5 type 2a genotype samples were analyzed. Approximately 31–42% of the nucleotide sequences of type 1b samples examined differed from those of different genotypes, In the case of type 2a samples, 36–42% of the nucleotide sequences differed from those of different genotypes. The diversities of the amino acid sequences were the same or greater than those of the nucleotide sequences. Two hypervariable regions (HVR1 and HVR2) were recognized in both HCV genomes of genotypes 1b and 2a. However, the sequence divergence within the HVR2 region of genotype 2a was less than that of genotype 1b. © 1995 Wiley‐Liss, Inc.
Relative frequency of human rotavirus VP4 (P) genotypes recovered over a ten‐year period from South African children with diarrhea
Authors: Mphahlele M. J. , Steele A. D.
Published: March 2007

The relative frequency and distribution of the VP4 (P) genotypes of 227 human rotavirus field strains were investigated in South Africa. The stool samples were collected between 1984‐1993 from infants and young children with diarrhea at Ga‐Rankuwa Hospital, Pretoria, South Africa. The RNA was extracted from stools, heat denatured, and dot blotted onto nylon membranes. The blots were hybridized to PCR‐gener‐ated, 32P radio‐labelled VP4‐specific probes (corresponding to the hyperdivergent region of the VP4 gene) of the following human rotavirus VP4 genotypes: P4, P6, P8, P9, P10, and P12. Of the 157 rotavirus strains typed by the probes, the P8 genotype was identified most frequently in 63.7% (n=100) of the samples. The P4 and P6 genotypes were detected less frequently in 22.3% (n=35) and 8.3% (n=13) of the samples, respectively. Five cases of dual infection between P8 and P4 genotypes occurred, indicating the potential for reassortment between members of different rotavirus genogroups. The P9 genotype could not be confirmed in 3 cases (1.9%), while the PI0 genotype was not observed at all, indicating the scarcity or absence of these VP4 genotypes in this region. Interestingly, we identified the newly‐described PI2 VP4 genotype in 6 cases (3.8%), suggesting a wide geographical distribution. Furthermore, several samples with sufficient RNA by gel electrophoresis remained untyped by the probes used in this study, and may represent putative “new” human VP4 genotype(S). © 1995 Wiley‐Liss, Inc.
Guinea pig and human cytomegaloviruses do not share cross‐reactive neutralizing epitopes
Authors: Adler Stuart P. , Shaw Kala V. , McVoy Michael , Burke Rae Lyn , Liu Hong
Published: March 2007

Human (HCMV) and guinea pig (gpCMV) cytomegaloviruses share biological similarities and DNA sequence homologies. Therefore, human and guinea pig sera were tested for cross‐reactive antibodies. In eight human sere (four HCMV‐seropositive and four HCMV‐seronegative), low levels of neutralizing activity against gpCMV were not associated with antibodies to HCMV. The convalescent sera of one of three humans infected with either HCMV Towne vaccine or wild‐type HCMV developed a fourfold increase in neutralizing titers to gpCMV after infection, but none of seven guinea pigs immunized with either HCMV Towne or purified HCMV gB developed neutralizing activity against gpCMV. Guinea pigs immunized with gpCMV did not develop antibodies to HCMV or human gB. Neither gpCMV, HCMV Towne stain or purified HCMV gB induced cross‐reactive antibodies against the heterologous virus as detected by enzyme immunoassay. Our results indicate that gpCMV and HCMV share a very limited number, if any, of cross‐reactive neutralizing epitopes. © 1995 Wiley‐Liss, Inc.
Genomic characterization of hepatitis C virus isolates from Argentina
Authors: Oubiña José Raúl , Quarleri Jorge Fabián , Rudzinski Marcelo , Parks Carlos , Badía Isabel , Cappa Stella Maris González
Published: March 2007

Thirty‐three Argentinian patients infected with hepatitis C virus (HCV) were studied for viral genotyping. The patients included 10 hemophiliac and 4 polytransfused children and 19 adults: 3 polytransfused, 7 dialyzed and 9 sporadic cases. Core‐based genotyping permitted the classification of 31 samples. Genotypes II, I and V were the most frequent: 21 (63.6%), 16 (48.4%) and 10 (30.3%) of the 33 patients, respectively. Only one polytransfused patient carried genotype IV. Genotype II was detected in 7 out of 9 sporadic cases. Thirteen patients (39.3%) were coinfected with two genotypes, and 2 others were coinfected with three genotypes. The remaining 2 samples which could not be typed were characterized following the restriction fragment length polymorphism (RFLP) method, and were classified as type 1. One of these had two consecutive transitional mutations in the 5′ untranslated region (5′ UTR). © 1995 Wiley‐Liss, Inc.
Direct detection of hepatitis C virus (HCV) RNA from whole blood, and comparison with HCV RNA in plasma and peripheral blood mononuclear cells
Authors: Schmidt Warren N. , Klinzman Donna , Labrecque Douglas R. , Macfarlane Donald E. , Stapleton Jack T.
Published: March 2007

Hepatitis C virus (HCV) requires reverse transcriptase‐polymerase chain reaction (RT‐PCR) or branched DNA signal amplification assays to be detected in patient samples. Although conventional methods of RNA isolation are employed for samples of serum, plasma, and peripheral blood mononuclear cells (PBMCs), whole blood is generally considered an unsuitable source of RNA because of abundant RNases and poly‐merase inhibitors. Using a cationic surfactant, Catrimox‐14, we adapted a procedure for RNA isolation from whole blood, plasma, and PBMCs that yields RNA template suitable for HCV RT‐PCR. RNA isolation required less than 2 hr, and HCV sequences were easily detected in sample volumes of 50 μl whole blood or plasma, and in less than 1 × l04 PBMC. Following the addition of blood to Catrimox, HCV RNA was stable in the mixture when incubated for at least 7 days at room temperature prior to RNA extraction. Comparison of whole blood HCV RNA and plasma HCV RNA from individuals with chronic hepatitis suggests that HCV RNA can be more reliably detected in whole blood. Three of 15 HCV antibody positive patients (20%) had HCV RNA present in whole blood but simultaneously obtained plasma samples were negative. Two of five HCV antibody negative individuals with chronic hepatitis contained HCV RNA in whole blood, yet one of these patient's plasma was negative for viral RNA. The Catrimox‐I4 method of RNA purification is useful for detecting HCV RNA in whole blood and blood subfractions, and provides a practical method of measuring plasma and PBMC HCV RNA from clinical specimens. © 1995 WiIey‐Liss, Inc.
Target structures for HIV‐1 inactivation by methylene blue and light
Authors: Bachmann Barbara , Knüver‐Hopf Josef , Lambrecht Bernd , Mohr Harald
Published: March 2007

In a photodynamic virus inactivation procedure for human fresh frozen plasma the plasma is exposed to visible light in the presence of 1 μM methylene blue. This procedure is known to inactivate HIV‐1 by at least 106.32 TCID50/ml within 10 minutes. To elucidate the mechanism of photo‐dynamic inactivation of HIV‐1 by methylene blue/light treatment, reverse transcriptase (RT), the HIV‐1 associated protein p24, and viral RNA were examined. In the dark, methylene blue up to 10 μM has no inhibitory effect on recombinant RT. In the presence of light, recombinant RT inactivation was dependent on illumination time and the concentration of methylene blue. After photoinactivation of the whole virus by methylene blue/light treatment, RT activity was also almost completely inhibited. Simultaneously, it was found by Western blotting that HIV‐1 p24 and gp120 are altered in size, possibly due to protein cross‐linking. In addition, it was shown by poly‐merase chain reaction (PCR) inhibition assay that HIV‐1 inactivation leads to destruction of its RNA. In summary, methylene blue/light treatment acts on HIV‐1 at different target sites: the envelope and core proteins, and the inner core structures RNA and RT. © 1995 WiIey‐Liss, Inc.
Hepatitis C virus infection in an HIV‐positive population in normandy: Antibodies, HCV RNA and genotype prevalence
Authors: Mendel Isabelle , Clotteau Laurent , Lambed Sylvie , Buffet‐Janvresse Claudine
Published: March 2007

The prevalence and the characteristics of hepatitis C virus infection (HCV) in 161 HIV‐positive patients were studied. HCV seroprevalence was determined by enzyme immunoassay and recombinant immunoblot assay (RIBA). Two different reverse transcriptase polymerase chain reaction (RT‐PCR) methods were also used to test the HCV‐seropositive samples and 50 EIA‐negative sera used as controls. The RNA HCV‐ positive sera were genotyped by the LiPA procedure. Associations of HCV status with demographic characteristics and risk factors were assessed by x2 and Fisher's exact tests. The seroprevalence of HCV was 34.2% with a significant difference between blood and sexual exposure risk groups (60.6% vs. 13.6%, respectively; P < 0.0001). Thirty‐six of the 55 anti‐HCV‐ positive sera were also positive for HCV RNA, and PCR detected HCV RNA in 8 HCV‐seronegative patients. Various RIBA profiles were found and all sera were positive for antibodies to the c33 protein. A proportion of sera had elevated levels of transaminase activity (37.2%), and abnormal liver function as associated with HCV infection. Forty‐two samples were genotyped and five genotypes and subtypes of the HCV virus were detected. Genotype la was the most frequent in this cohort, although genotype 1b is generally more common in France. The majority (94.1%) of the patients with genotype 1a had a history of blood exposure, which may account for the difference. © Wiley‐Liss, Inc.
Study of norwalk‐related viruses in mexican children
Authors: Jiang X. , Matson D. O. , Velazquez F. R. , Calva J. J. , Zhong W. M. , Hu J. , Ruiz‐Palacios G. M. , Pickering L. K.
Published: March 2007

Two‐hundred Mexican children monitored from birth to 2 years of age in a cohort study of diarrhea were tested for Norwalk virus (NV) and Nor‐walk‐related virus infection. Blood was collected quarterly and tested by an enzyme immunoassay (EIA) using the recombinant NV (rNV) particles as antigen. Stool was collected weekly and tested by an EIA using hyperimmune antisera from animals immunized with rNV and a reverse transcription‐polymerase chain reaction (RT‐PCR) with primers in the RNA polymerase region of NV. A high prevalence of serum antibody to NV (85% at age 2 years) was found by the antibody EIA. In 54 stool specimens selected from children who developed a high titer of serum antibody to rNV, none was positive for NV by the antigen EIA, but 6 yielded products by the RT‐ PCR. One stool specimen (MX virus) yielded a 3.3 kb RT‐PCR product from the 3′ end of the viral genome. The MX virus cDNA has a genomic organization like other caliciviruses. Sequence comparison showed that MX virus shares 80% nucleic acid and 91% amino acid sequence identity with Snow Mountain agent (SMA), but only 62% and 60% identity, respectively, with NV in the RNA polymerase region, suggesting that MX virus is a SMA‐like virus. © Wiley‐Liss, Inc.
Serological and salivary markers compared with biochemical markers for monitoring interferon treatment for hepatitis C virus infection
Authors: Roy Kirsty M. , Bagg Jeremy , Bird George L. A. , Spence Elizabeth , Follett Edward A. , Mills Peter R. , Lau Johnson Y. N.
Published: March 2007

Paired serum and saliva specimens were collected on a regular basis from 18 asymptomatic blood donors participating in a controlled clinical trial of interferon alpha 2a (IFN) treatment of chronic hepatitis C virus (HCV) infection. Nine patients were randomised to receive interferon and nine to observation only. Serum and salivary HCV RNA was detected by a “nested” polymerase chain reaction (PCR) assay. Complete follow‐up data were available for 14 patients (7 treated and 7 untreated). Serum ALT levels declined to normal in five of the seven IFN‐treated patients by the twelfth week. Of these five, loss of hepatitis C viraemia was observed in three. Of the seven treated patients, the three responders had a lower viraemia level than the partial or nonresponders. Both nonresponders had infection with type 1 HCV, but the complete and partial responders were infected with types 2 or 3. HCV RNA was detected in the saliva of all seven observation patients during the follow‐up period. HCV was also detected in the saliva of the two patients who did not respond to IFN treatment. No correlation was shown between the level of HCV RNA in serum and the presence of HCV RNA in saliva. A role for noninvasive salivary investigations in monitoring treatment is possible, but further refinement of the methodology is required. © Wiley‐Liss, Inc.
physics of surgical lasers
Authors: Fuller T. A.
Published: March 2007

The fundamental physical properties of lasers are discussed. Included in this presentation is a discussion of carbon dioxide, argon, neodymium:YAG and ruby lasers. Laser optics and beam characteristics as well as Q‐switching are presented. Ocular hazards of lasers and preventive measures are discussed.
Partial ciliary process laser photocoagulation in the management of glaucoma
Authors: Lee Pei‐Fei , Shihab Zuhair , Eberle Marilyn
Published: March 2007

Partial ciliary processes argon laser photocoagulation (PCLP) in the management of glaucoma has been the subject of a carefully conducted, prospective 5+‐year clinical trial in 22 eyes of 20 patients. The mean intraocular pressure (IOP) ± SD was significantly lower (15.5 ± 3.6 mm Hg) than before the procedure (29.9 ± 10.1 mm Hg; 0.001 < P < 0.005, paired t‐test). The mechanism of intraocular pressure reduction is due mainly to the reduction in the rate of aqueous humor formation with a mean outflow facility (C‐value) ± SD of 0.12 ± 0.11 before and 0.1 2 ± 0.06 μl/min/mm Hg after the procedure. This new procedure, done on an out‐patient basis, shows promise as a convenient, low‐risk, and useful alternative procedure in selected glaucoma cases that are poorly controlled by medical or surgical measures. This new approach may also be used as an adjunct in the medical and/or surgical management of aphakic and ciliary block glaucoma.
Co2 laser in vitreoretinal surgery
Authors: Karlin David B. , Patel C. K. N. , Wood O. R. , Llovera Irene
Published: March 2007

Radiation from a CO2 laser has the dual effect of phototransection and photo‐coagulation. Incisions have been made in scleral‐chorioretinal tissue, lens tissue, and the vitreous body (with and without membrane formation). Results indicate that the CO2 laser may be useful in intravitreal surgery. Its simultaneous cutting and coagulating properties may make the experimental trans‐vitreal chorioretinal biopsy reported by Griffin et al [12] and the full‐thickness ocular wall resection for small melanosarcomas of the choroid reported by Peyman and Sanders [13] clinical possibilities in the not too distant future. Finally, the effects of CO2 laser radiation on the normal human lens suggests the possibility of the dissolution of cataracts by laser irradiation.
Development of a carbon dioxide laser cystoscope
Authors: Willscher Max K. , Filoso Anthony M. , Jako Geza J. , Olsson Carl A.
Published: March 2007

CO2 laser lesions were created at varying power densities on the exteriorized canine bladders. A 50‐watt carbon dioxide continuous laser coupled to a Zeiss surgical microscope was used. A schematic power curve was developed indexing depth of bladder penetration by the laser against laser energy output. Once the optimal power settings for the carbon dioxide laser were established, vertical heat transmission, hemostasis, and healing were studied. A prototype carbon dioxide laser cystoscope was then constructed that allowed endoscopic delivery of the CO2 laser beam into the intact canine bladder. The beam was focussed by a germanium lens and directed out the end of the endoscope, using a movable mirror. Eight dogs were then endoscopically studied in vivo.
Experimental Study of Laser Photocoagulation in the Treatment of Bleeding Canine Gastric Ulcers
Authors: Escourrou J. , Frexinos J. , Rumeau J. L. , Monrozies X. , Balas D. , Ribet A.
Published: March 2007

We report experimental results obtained by laser photocoagulation on hemorrhagic lesions induced in dogs. The aims of this study were 1) to evaluate the real efficiency of the YAG laser to ensure hemostasis of briskly bleeding lesions; 2) to determine the minimum energy density necessary to ensure hemostasis; 3) to assess the damage depth inside the gastric wall after photocoagulation; 4) to compare reepithelialization of treated ulcers with that of control ulcers; 5) to evaluate the safety margin for the clinical use of the YAG laser.
Partial splenectomy with CO2 laser: An experimental study
Authors: Snider W. Ray , Li Shu‐Jun
Published: March 2007

A freehand carbon dioxide laser is now available for surgical procedures. A comparison of its utility with the electrocautery was carried out in five dogs by the performance of hemisplenectomy. All dogs survived without complications. The laser proved to be an effective instrument for partial splenectomy under the terms of the experiment.
Present and future plans for laser urological surgery
Authors: Bülow Hartwig
Published: March 2007

A report is given on the present status of laser techniques in open as well as transurethral urological surgery. Future aspects of laser technical development and clinical applications are described and discussed.
Microsurgery of the fallopian tube with the carbon dioxide laser: Eighty‐two cases with follow‐up
Authors: Bellina Joseph H.
Published: March 2007

In 1974 the carbon dioxide laser was adapted to the operating microscope for reconstructive pelvic surgery and the first 15 cases of laser tubal microsurgery were performed. The instrumentation and techniques were refined. A protocol was designed to test the efficacy of this surgical modality, and a new study was begun in 1980. Complete documentation of laparoscopic findings, surgical techniques, and pre‐ and postoperative hysterosalpingograms are kept on videotapes. Detailed descriptions of the surgical techniques employed in these cases are presented in this paper. Preliminary results are reported in terms of patency and pregnancy rates experienced to date.

Eighty‐two women experienced fertility enhancement laser microsurgery at the Reproductive Biology Center at F. Edward Hebert Memorial Hospital in New Orleans. Bilateral patency or patency of the only existing fallopian tube was demonstrated postoperatively in 93% of the cases. Eliminating the women practicing contraception, those on postoperative Danazol therapy for endometriosis, male factors, or other reasons for women or their partners being not at risk, conception has occurred 21 times among 20 of 42 patients at risk. Many of the women were referral cases who had had unsuccessful microsurgery or were rejected for microsurgery by their physicians due to extensive disease. These results indicate that the carbon dioxide surgical laser may be a useful adjunct in reconstructive microsurgery for fertility dysfunction.
Clinical application of the Nd:YAG laser endoscopy
Authors: Sasako Mitsuru , Iwasaki Masaru , Konishi Toshiro , Maruyama Yuji , Wada Tatsuo
Published: March 2007

We report here our clinical experiences with Nd:YAG laser therapy, and evaluate the results of this treatment. From July 1980 to December 1981, we carried out endoscopic laser treatment for 31 patients with 33 lesions. Bleeding gastric ulcers except stomal ulcers were treated successfully. For mucosal lesions of the stomach, Nd:YAG laser irradiation was effective in extirpating them. In advanced gastric cancers, symptoms of cardiac stenosis could be relieved in 80% of the cases. Endoscopic laser therapy was also effective in 80% of postoperative stenosis in the gastrointestinal tract. It is concluded that endoscopic irradiation with the Nd:YAG laser is useful for hemostasis and also for the treatment of malignant tumors and stenosis of the gastrointestinal tract.
Experimental study of partial liver resection with a combined CO2 and Nd:YAG laser
Authors: Meyer H.‐J. , Haverkampf K.
Published: March 2007

The use of the CO2 laser in liver surgery is mainly limited by the lack of coagulation of the larger vessels. In an experimental study, partial liver resections were performed on pigs with a Nd:YAG as well as with a combined CO2 and Nd: YAG laser. The best cutting efficiency was obtained with the CO2 laser. On the other hand, the Nd:YAG laser and the combined laser sources showed excellent hemostasis at the cutting edge corresponding with a width of necrosis at about 5 mm in histomorphometric examination and zones with histologically different characteristics. Rebleedings from the resection lines were avoided in all cases using the combined CO2 and Nd:YAG laser.
Laser photoradiation therapy of cancer following hematoporphyrin sensitization
Authors: Wile Alan G. , Dahlman Anton , Burns Robert G. , Berns Michael W.
Published: March 2007

Hematoporphyrin derivative‐photoradiation therapy (HPD‐PRT) of human malignancy has been performed on 267 tumor sites in 50 patients. Tumor response has been assayed at 24 hours and one month following treatment with 625–635 nm light from an argon laser‐pumped dye laser. The majority of tumors treated were dermal breast cancer recurrences (21 cases), local recurrence of ENT squamous cell carcinomas (16 cases), and ENT cutaneous metastases of squamous cell carcinomas (9 cases). A 30‐day favorable response was judged to be either complete regression of the tumor or reduction of tumor diameter by greater than 50%. The above categories of tumors had a combined favorable response of 81%. Appropriate dosimetry is discussed.
Update on laser usage in treatment of decorative tattoos
Authors: Apfelberg David B. , Rivers Janis , Maser Morton R. , Lash Harvey
Published: March 2007

This report updates our most recent series of 60 tattoos treated in 1980 and followed for at least 12 months. An initial rate of hypertrophic scarring of 35% at 3 months eventuated in 23% after 1 year. Factors such as sex, complexion, and body location were correlated to scars and hypopigmentation. Over 50% excellent to good results were achieved overall in this series.
Effects of laser guided by optic fiber into rat brain on conditioned avoidance response and brain chemistry
Authors: Shen‐Zheng  , Xiao‐Jian  , Shu‐Zhi Lin , Li‐Hua Wang
Published: March 2007

Low power lasers were guided by optic fibers into the rat caudate nucleus or frontal cortex, during conditioned avoidance response (CAR) training. The changes in striatal monoamine and amino acid concentrations were subsequently determined. Of six training groups tested, only the experimental group with helium‐neon laser radiation to the caudate nucleus exhibited the formation of CAR and an increase of unconditioned leg contractions. The striatal concentrations of dopamine (DA) and norepinephrine (NE) were increased simultaneously in the group.
Advanced surgical instrumentation needed for intra‐abdominal application of the carbon dioxide laser in reproductive biology
Authors: McLaughlin David S.
Published: March 2007

Rapidly expanding laser technology has created a void in surgical instrumentation when the carbon dioxide laser is applied to intra‐abdominal microlaser fertility‐promoting procedures. By using proper instruments, the laser microsurgeon will be able to enhance his surgical technique as well as reduce his frustrations.
Research and development of additional aids for dermatologic and plastic surgery
Authors: Goldman Leon , Stefanovsky David , Gregory Richard O. , Bauman Wayne , Koch Michael
Published: March 2007

Increasing numbers of accessories continue to be found to make laser surgery more effective for dermatologic and plastic surgery. Argon laser surgery aids are available to increase the dilatation of the superficial vessels and to localize increasing numbers of red cell masses. Laser probes for intravascular thrombogenesis and thrombolysis have now been adapted for intradermal and deep dermal tissues and for cardiology. Studies on laser effects on platelets and heat transmission and thromboembolic phenomena are lacking. Investigative studies are developing for laser fiber optic probes for laser‐induced fluorescence, not only for oncology, but also for studies of metabolism of tissues and also for spectroscopy. The use of different wavelengths and shorter pulses, more flexible fiber‐optics transmission for all laser systems, combinations of laser systems into a single operating probe, as well as the increased use of lasers for diagnosis and treatment will all stimulate the development of new aids for laser surgery. Cooperative programs developed jointly by dermatologic and plastic surgeons will make for great progress in skin and soft‐tissue laser surgery.
Comparative Gross and Histological Study of the Effects of Scalpel, Electric Knife, and Carbon Dioxide Laser on Skin and Uterine Incisions in Dogs
Authors: Montgomery Tom C. , Sharp James B. , Bellina Joseph H. , Ross Lynne F.
Published: March 2007

This study concerns the gross histological effects of scalpel, electric knife, and carbon dioxide laser incisions on skin and uterine tissue in dogs. Tissue studies comparing the carbon dioxide laser with the scalpel and electric knife have frequented the literature. However, a gross and histological comparison specifically involving uterine tissue is not presently known to have been reported. The evaluation on this series of animals considers both the skin and the uterus in an abdominal approach to evaluate the carbon dioxide laser for potential intrauterine surgery. Tissue sampling of both skin and uterus at 2, 6, and 8 weeks postoperatively were histologically examined to evaluate healing rates and degree of scar formation.
A Study of the Effects of Lasering on Chronic Bowed Tendons at Wheatley Hall Farm Limited, Canada, January, 1983
Authors: McKibbin L. S. , Paraschak D. M.
Published: March 2007

Chronic bowed tendons of horses have been lasered with an infrared 904‐nm laser at Wheatley Hall Farm Limited since 1980. A sample of 42 single injury/single treatment standardbreds which were racing within 120 days of laser treatment and met certain criteria, were evaluated for final race times, last quarter race times, and class changes.

Results indicate that a significant percent of the standardbreds raced with similar or improved times and classes. Lasering bowed tendons presents a safe and less expensive alternative to traditional treatment methods which often requires a year layoff for the horse.
A Preliminary Study on Clinical Application of Nd:YAG Laser to the Face and Head
Authors: Arai Katsuyuki , Waseda Toyomi , Ota Hideki , Azuma Takeshi , Nagasawa Akinori
Published: March 2007

Preliminary experiments were carried out for use of the Nd:YAG laser therapy of malignant tumors of the head and face. Because bone and brain tissue lie under the soft tissues in the face and head, the authors prepared two experimental models and examined the thermal effects of laser irradiation using three irradiating methods, single‐pulse, automatic running, and manual. In experiments using results from these models, a temperature rise inducing protein coagulation did not occur under the surface of the soft tissue under the bone in both models. With automatic running irradiation, the temperature rise in the surface of the soft tissue under the bone was about 5°C at 60 W with a running speed of 4 mm/sec in model I. These conditions were considered to be sufficiently within safe limits. In the second model, it was estimated that no thermal effects would be exerted on the soft tissue under the bone at 60 W or less with a running speed of 8 mm/sec or less. Using manual irradiation, no thermal disturbance of the soft tissue under the bone was induced in the first model, but without a shortening of irradiation time or an increase in irradiation distance this method could cause thermal damage to the second model and must be taken into consideration.
Effect of CO2 Laser on the Luminal Surface of Blood Vessels In Vivo
Authors: Treat Michael R. , Weld Francis M. , White John V. , Forde Kenneth A. , Fenoglio John J. , L'Esperance Francis , Voorhees Arthur B.
Published: March 2007

The use of lasers as surgical tools may open up new possibilities for the treatment of atherosclerotic occlusive vascular disease. However, basic information regarding the effect of laser radiation to the lumen of normal blood vessels is needed prior to clinical application.

This work investigates the nature of the CO2 laser‐induced vascular wound and the time course of its healing in the rabbit aorta. The chief short‐term problem with CO2 laser radiation of the luminal surface of blood vessels is thrombosis.
Nonthermal Effects of Nd:YAG Laser on Biological Functions of Human Skin Fibroblasts in Culture
Authors: Abergel R. Patrick , Meeker Cheryl A. , Dwyer Richard M. , Lesavoy Malcolm A. , Uitto Jouni
Published: March 2007

Previous studies have indicated that laser can selectively affect the biological functions of cells. In the present study, the role of a thermal component in laser‐induced alterations in the biology of human skin fibroblasts was examined. Cells were cultured on 96‐well tissue culture plates, subjected to treatment with the Nd.YAG laser (wavelength 1,064 nm), and the temperature of the medium was monitored by a microprobe connected to a telethermometer. For comparison, parallel cultures were heated to the same temperatures by tungsten‐halogen lamp. The cell cultures were analyzed for collagen synthesis by incubating the cultures with [3H]proline, and the collagen production was assayed by the synthesis of nondialyzable [3H]hydroxyproline. The rate of DNA replication was also determined by measuring the uptake of [3H]thymidine. A marked decrease of collagen production and thymidine incorporation was noted in the cultures subjected to Nd.YAG laser. No suchdecreases were noted in cultures heated to the corresponding temperatures by tungsten‐halogen lamp. The results thus indicate that the biochemical alteration caused by the Nd.YAG laser in human fibroblast functions cannot be explained on the basis of thermal effects.
Enhanced tumor control following sequential treatments of photodynamic therapy (PDT) and localized microwave hyperthermia in vivo
Authors: Waldow Stephen M. , Henderson Barbara W. , Dougherty Thomas J.
Published: March 2007

Photodynamic therapy (PDT), or photoradiation therapy (PRT), utilizing hematoprophyrin derivative (HPD) as photosensitizer and an argon‐dye laser system as the light source, was used alone and in combination with localized microwave hyperthermia (2450 MHz) to treat axillary tumors of the SMT‐F mammary carcinoma in mice. Thirty‐minute heat treatment were applied either immediately before or immediately after a standard PDT treatment of 630 nm light at 75 mW/cm2 for 30 min (135 J/cm2) given 24 hr post‐7.5 mg/kg HPD, intraperitoneally (i.p.). Tumor control as judged by lack of tumor regrowth 35 days or longer after the combined treatments was compared to that following each treatment when alone.

Little or no enhancement of tumor control was seen when sublethal temperatures of 37.5, 38.5, and 39,5 °C were applied for 30 min immediately following the PDT treatment. However, increasing levels of enhancement were seen when heat treatment of 0.5 and 41.5 °C, given for 30 min, were applied immediately before or after the photodynamic treatment.
Use of the argon and carbon dioxide lasers for treatment of superficial venous varicosities of the lower extremity
Authors: Apfelberg David B. , Maser Morton R. , Lash Harvey , White David N. , Flores Jasmin T.
Published: March 2007

Superficial telangiectasia of the lower extremity in 38 patients was treated with both argon and CO2 lasers. Results after five months revealed no change or worsening of the veins in 49% of the patients and good to excellent improvement or segmentation in 16% of the patients. The most common complication was brown hemosiderin bruising in almost half of the patients.
Laser treatment of keloids: A clinical trial and an in vitro study with Nd:YAG laser
Authors: Abergel R. Patrick , Dwyer Richard M. , Meeker Cheryl A. , Uitto Jouni , Lask Gary , Kelly A. Paul
Published: March 2007

Biochemical studies utilizing keloid fibroblast cultures revealed that Nd: YAG laser selectively suppressed collagen production by these cells. Based on these in vitro observations, eight patients with keloids were treated with Nd:YAG laser in a nondestructive manner. Results, with a 3‐year follow‐up, indicated flattening and softening of the lesions. Thus, the results suggest that Nd:YAG laser is an effective treatment modality for keloids, and its mechanism may involve bioinhibition of fibroblast functions.
Treatment of dental decay by CO2 laser beam: Preliminary results
Authors: Melcer J. , Chaumette M. T. , Melcer F. , Dejardin J. , Hassson R. , Merard R. , Pinaudeau Y. , Weill R.
Published: March 2007

Results obtained from two clinical cases, representative of 1,140 human teeth treated by CO2 laser beam during 3 years, announce a new conception of treatment of dental caries. The beam (P = 4 – 5 W, energy density of 9 to 25 kw/cm2) causes a dentin healing which becomes sterile, chemically and physically more resistant than pathological dentin. In addition, this exposure leads to an activation of the dentinogenesis supported by X‐ray, confirming histo‐pathological results obtained from experiments performed on animals.
Ultrastructural and pharmacologic studies on laser‐induced glaucoma in primates and rabbits
Authors: March Wayne F. , Gherezghiher Tseggai , Nordquist Robert , Koss Michael
Published: March 2007

Sustained high intraocular pressure resulting in optic nerve cupping and loss of ganglion cells was produced in five rhesus monkeys and eight pigmented rabbits by applying argon laser energy to the trabecular mesh work. In addition, the rabbits manifested buphthalmus. Flow of carbon particles subsequently injected into the anterior chamber was obstructed at the trabecular meshwork by a wound‐healing response that closed the intratrabecular spaces. Besides this sustained high intraocular pressure as a result of late scarring, an acute hypertensive response was seen in all rabbits which may correspond to the acute hypertension seen after laser trabeculoplasty in humans. The acute hypertensive response could be only partially blocked by prostaglandin inhibitors and we believe that prostaglandins are not primarily responsible for this effect. Medications known to lower intraocular pressure were systematically tested in both glaucoma models.
Argon laser photocoagulation in the management of retinal detachment and predisposing lesions
Authors: Gratton I. , Gazocchi M. , Simonini F. , Fattori C. M. , Citroni M.
Published: March 2007

During the years 1979–1982 we treated by argon laser photocoagulation 863 eyes of 551 patients affected by peripheral retinal degenerations and breaks. No case of progression to retinal detachment has been registered so far.

In the same period, we treated 42 patients affected by retinal detachment of different topography (three posterior pole and 39 peripheral detachments) and size (mostly limited detachments, 12 as large as a quadrant, two larger than a quadrant). In 41 of these 42 eyes, the retina is still firmly attached after a 1‐ to 4‐year follow‐up, while in one case it was necessary to proceed surgically following a relapse.

While argon laser photocoagulation is certainly the first choice treatment of retinal degenerations and breaks, it also appears to be a reliable alternative to scleral buckling in the management of specific cases of retinal detachment.
The effect of epidermal pigmentation on selective vascular effects of pulsed laser
Authors: Tan O. T. , Kerschmann Russell , Parrish John A.
Published: March 2007

The effect of epidermal pigmentation on the threshold exposure dose for inducing purpura with a tunable dye laser at 577 nm, 1.5 μs pulse duration, was studied in 21 human volunteers with varied genetically determined amounts of melanin. More laser energy was required to produce purpura as constitutive skin pigmentation increased. Histology showed that, in lighter skin, the laser threshold dose produced the most specific vascular injury with no disruption of surrounding structures. In more pigmented skin, damage occurred in the epidermal basal layer and very few changes were seen in blood vessels below.
Nd:YAG laser followed by radiation for treatment of malignant airway lesions
Authors: Jain Puspha Rani , Dedhia Harakh V. , Leroy Lapp N. , Thompson Austin B. , Frich John C.
Published: March 2007

Patients with malignant obstructive airway lesions often present with total or segmental atelectasis of lung. In spite of prompt initiation of palliative external radiation alone, some patients were unable to complete the planned course of radiation therapy.

Since May 1983, 17 patients with malignant obstructive endobronchial lesions have been treated by endoscopic Nd:YAG laser vaporization of the tumor. One to seven days later, fractionated external radiation therapy was initiated. Endoscopic use of the laser was repeated as needed during the course of treatment. Fifteen out of 17 patients successfully completed the planned course of therapy. The improved performance status was sustained in 13 of 15 patients for 2‐13 months. A control group was selected from among patients with similarly located lesions who underwent external radiation treatment only prior to the availability of the Nd:YAG laser therapy.

One patient developed radiation pneumonitis six weeks after completion of a second course of external radiation, another patient developed bronchopleural fistula after laser treatment which healed following closed chest tube drainage. The others had longer palliation of symptoms and improved quality of life. The results indicate that relief of airway obstruction by use of the Nd:YAG laser improved the patients' ability to tolerate subsequent external radiation treatment.
Temperature rise in biological tissue during Nd:YAG laser irradiation
Authors: Marchesini R. , Andreola S. , Emanuelli H. , Melloni E. , Schiroli A. , Spinelli P. , Fava G.
Published: March 2007

Few data are available about temperature distribution in tissue during Nd:YAG laser irradiation. To study the heat distribution that produces tissue coagulation, we used a thermographic camera aimed orthogonally to the laser beam axis to obtain thermal maps. Immediately after surgical resection, specimens of human stomach were irradiated near the resected edge, and the heat emitted sideways was detected by an infrared image system. A magnifying lens mounted on the camera enabled us to obtain 0.1 mm spatial resolution of the isothermic curves. The thermal analysis showed that the maximum depth where the increase in temperature reached 25 °C (corresponding to a coagulation temperature of about 60°C) was never greater than 3 mm, irrespective of the power and exposure time used. Moreover, the bidimensional thermal maps showed that the temperature did not decrease in a purely exponential fashion along the beam axis, but reached a maximum at about 1 mm beneath the surface. This fact, which confirms the decrepitation theorem, could explain the explosion inside the tissues observed in surgical application of the Nd:YAG laser.
Treatment of benign, semimalignant, and malignant skin tumors with the Nd:YAG laser
Authors: Brunner Reinhold , Landthaler Michael , Haina Diether , Waidelich Wilhelm , Braun‐Falco Otto
Published: March 2007

Reported are first experiences with Nd.YAG laser treatment of benign, semimalignant, and malignant skin tumors in 90 patients. Treated lesions included condylomata acuminata, basal cell carcinomas, solar keratosis, squamous cell carcinomas, and secondary malignant skin tumors. First clinical and histological results are promising, but long‐term follow‐up is required to judge the definite efficacy of this therapeutical modality.
Effect of laser radiation on tissue during laser angioplasty
Authors: Welch A. J. , Valvano J. W. , Pearce J. A. , Hayes L. J. , Motamedi M.
Published: March 2007

The thermal properties of adipose and ceramic atherosclerotic plaque deposits and normal arterial vessel wall were measured in the temperature range of 25−95°C. In general, the data indicate that fatty plaques exhibit the lowest thermal conductivity and thermal diffusivity of the three types, whereas calcified plaques seem to have the highest values. By using a video scanning thermograph, temperature rise was recorded in normal vessel wall and plaque during ablation of tissue. Theoretical analysis suggested that realistic modeling of laser angioplasty should account for scattering of light, water content, and ablation. This paper is a preliminary report of these results.
Microvascular anastomosis using the milliwatt CO2 laser
Authors: Quigley Matthew R. , Bailes Julian E. , Kwaan Hau C. , Cerullo Leonard J. , Brown J. Thomas , Lastre Clara , Monma Dean
Published: March 2007

The milliwatt CO2 laser was used to anastomose small vessels in a rat femoral artery model. The technique requires multiple brief applications of 60–70 mW after placement of three equidistant 10–0 nylon stay sutures. The vessel histology is described immediately and 1, 3, 7, and 21 days after the procedure. The laser effects tissue bonding through changes in the collagen of the adventitia and media. Subsequent healing consists of new collagen deposition in the adventitia and re‐endothelialization of the intima associated with neointimal proliferation at 3 weeks.
Corneal incisions produced with the fourth harmonic (266 nm) of the YAG laser
Authors: Berns Michael W. , Gaster Ronald N.
Published: March 2007

The fourth harmonic wavelength (266 nm) of a neodymium YAG laser was used to cut precise grooves on the surface of the human cornea. Well‐controlled cuts were made using the laser operating at 1.3 kHz. The width of the grooves was 2–3 μm. The depth could be controlled by varying the amount of laser exposure.
CO2 laser and suture in splenic parenchyma: An experimental study
Authors: Goldenberg Alberto , Goldenberg Saul , Neto João Guidugli , Chacon Jesus Pan
Published: March 2007

Hemisplenectomy was performed with the scalpel in 12 mongrel dogs. The blood vessels of the splenic pedicle were temporarily clamped. In a six‐dog group, hemostatis was obtained by CO2 laser and residual bleeding was controlled by sutures. In the other six dogs, group hemostasis was performed only by sutures. The surgical procedure was free of mortality. No hematological changes were observed in both groups. Histological studies revealed a better hemostatic effect and intensive necrosis of the splenic parenchyma in the lasered group compared with the sutured group.
Evaluation of the carbon dioxide laser for performance of gastrointestinal myotomies
Authors: LoCicero Joseph , Frederiksen James W. , Hartz Renee S. , Kaufman Michael W. , Michaelis Lawrence L.
Published: March 2007

Using a conventional carbon dioxide laser set at 8‐W continuous‐wave energy, a technique was developed in the animal laboratory to incise only the muscularis of the pylorus leaving the mucosa and submucosa intact. Similar esophageal myotomies were performed with less success, due to the rich submucosal venous plexus causing obscuring hemorrhage and to the reapproximation of the longitudinal esophageal muscle over a 3‐week period. The technique for esophageal myotomy requires further refinement, but pyloromyotomy appears applicable for controlled human trials.
“Hot tip”: Another method of laser vascular recanalization
Authors: Abela George S. , Fenech Albert , Crea Filippo , Richard Conti C.
Published: March 2007

This study is a preliminary report evaluating the use of laser radiation to heat a metal‐capped fiber for arterial recanalization. The method was compared to the currently used bare‐ended fiber for recanalization of occluded vessels. The model used was a human coronary artery xenograft transplanted in the femoral artery of the dog. At 4 weeks following the transplantation, laser recanalization was attempted using the heated metal probe (“hot tip”) in five arteries and the bare fiber in another five arteries. Results: 1) Angiography demonstrated recanalization in all five arteries treated with the “hot tip” and three of the five arteries treated with the bare fiber. 2) Only one perforation occurred with the “hot tip,” whereas three perforations occurred with the bare fiber. 3) The larger metal cap was capable of creating a wider channel in the occluded arterial segment. Although the trend favored the heated metal cap in terms of recanalization and less perforation than the bare fiber, the total number of experiments were not adequate to demonstrate statistical significance. Microscopic examination of the vessels recanalized by either technique was similar. Characteristic charring at the recanalization site was seen regardless of the technique used. These observations suggest that the effect of direct laser radiation on plaques is predominantly a thermal effect. Although these results would suggest utilization of a metal‐capped fiber for vascular recanalization, more studies need to be done to confirm these preliminary findings.