Comparison of two different transection techniques in liver surgery-an experimental study in a porcine model.

AIMS: Postoperative morbidity and mortality after liver resection is closely related to the degree of intraoperative blood loss; the majority of which occurs during transection of the liver parenchyma. Many approaches and devices have therefore been developed to limit bleeding, but none has yet achieved perfect results up to now. The aim of this standardized chronic animal study was to compare the safety and efficacy of the LigaSure™ Vessel Sealing System (LVSS) with the stapler technique, which is one of the modern techniques for transecting the parenchyma in liver surgery. METHODS: Sixteen pigs underwent a left liver resection (LLR). Eight pigs received a LLR by means of an Endo GIA, whereas the other eight pigs underwent liver parenchymal transection followed by simultaneous sealing by the LVSS. The operating time, transection time, blood loss during transection, and time of hemostasis were measured on the day of LLR (postoperative day 0/POD 0). Animals were re-explored on postoperative day 7 (POD 7) and the transection surface of remnant liver was observed for fluid collection (hematoma, biloma, and abscess), necrosis, and other pathologies. A biopsy was taken from the area of transection for histopathological examination. RESULTS: All animals survived until POD 7. Operating time and transection time of the liver parenchyma on POD 0 was significantly shorter in the stapler group. There was no significant difference between the two groups in terms of blood loss during transection, time of hemostasis and number of sutures for hemostasis on POD 0, morbidity rate, as well as the histopathological examination on POD 7. Furthermore, the material costs were significantly higher in the stapler group than in the LVSS group. CONCLUSION: In this standardized chronic animal study concerning transection of the parenchyma in liver surgery, LVSS seems not only to be safe, but also comparable with the stapler technique in terms of morbidity and mortality. Additionally, LVSS significantly reduces material costs. However, the transection time is significantly longer for LVSS than for the stapler resection technique.

An analysis of anthropometric data on Iranian primary school children.

BACKGROUND: Anthropometric data can be used to identify the physical dimensions of equipment, furniture, etc. The use of furniture that fails to fulfill the anthropometric data of its users has a negative impact on human health. Specific anthropometric dimensions are necessary to design school furniture. Anthropometric data have been measured in many communities especially among schoolchildren. There are different ethnic groups with probably different anthropometric data in Iran, and anthropometric data can change by time, so gathering data about anthropometric dimensions is important. This study was designed to obtain anthropometric dimensions of Iranian children (Fars ethnicity) aged 7-11 years. METHODS: In a cross-sectional study in Yazd, Iran, descriptive statistics as well as key percentiles for 17 static anthropometric data of primary school students (1015 males and 1015 females), were measured and compared between boys and girls. RESULTS: The age of the students was between 6 and 11 years. Mean weight was between 21.56±5.33 kg and 36.63±9.45 kg in boys and between 20.79±3.48 kg and 35.88±9.40 kg in girls. Mean height was between 1187/02±53.98 mm and 1420.83± 69.39 mm in boys and between 1173.90±51.01mm and 1421.27±70.82 mm in girls. There was also some difference in other anthropometric data between two genders. CONCLUSION: Results of this study showed some differences in anthropometric data with other studies. We also observed significant gender differences in some dimensions as well.

Backpack weight and musculoskeletal symptoms in secondary school students, tehran, iran.

BACKGROUND: Increased complaints by school students about back and shoulder pain and discomfort have raised concerns among parents, education professionals, and orthopedists and these discomforts may be because of schoolbag carriage. The aim of this study was to investigate of relationship of musculoskeletal symptoms with weight of backpack in Tehran secondary school students. METHODS: This cross-sectional study was performed in the city of Tehran in 2009. Two hundred thirteen students participated in study. Nordic Musculoskeletal Questionnaire was used, asking about complaints of back, neck, and/or shoulders. Length and weight of the children were determined. Schoolbags were weighed, and the relative weight of the schoolbag was calculated. RESULTS: Most prevalent musculoskeletal discomfort was in shoulders as 38.1%, neck 27.6% and back 16.7%. Average difference of weight of backpack in sample that had musculoskeletal with other samples was significant (P< 0.05). CONCLUSION: Weight of the backpack appears to be strongly related to the occurrence of shoulder, neck, back, and extremities complaints in students. Although musculoskeletal discomforts are believed to be multifactorial in origin, the carriage and manipulating of heavy backpack is signally a suspected factor and may represent an overlooked daily physical stress for secondary students.

Antibacterial effects of Eucalyptus globulus leaf extract on pathogenic bacteria isolated from specimens of patients with respiratory tract disorders.

The antibacterial activity of Eucalyptus globulus leaf extract was determined for 56 isolates of Staphylococcus aureus, 25 isolates of Streptococcus pyogenes, 12 isolates of Streptococcus pneumoniae and seven isolates of Haemophilus influenzae obtained from 200 clinical specimens of patients with respiratory tract disorders. MIC50s for these species were 64, 32, 16 and 16 mg/L, respectively; MIC90s were 128, 64, 32 and 32 mg/L, respectively; and MBCs were 512, 128, 64 and 64 mg/L, respectively. These results suggest that further studies to clarify the possible therapeutic role of E. globulus leaf extract in the treatment of respiratory tract infection are warranted.

Lys75 of Anabaena ferredoxin-NADP+ reductase is a critical residue for binding ferredoxin and flavodoxin during electron transfer.

Previous studies, and the three-dimensional structure of Anabaena PCC 7119 ferredoxin-NADP+ reductase (FNR), indicate that the positive charge of Lys75 might be directly involved in the interaction between FNR and its protein partners, ferredoxin (Fd) and flavodoxin (Fld). To assess this possibility, this residue has been replaced by another positively charged residue, Arg, by two uncharged residues, Gln and Ser, and by a negatively charged residue, Glu. UV-vis absorption, fluorescence, and CD spectroscopies of these FNR mutants (Lys75Arg, Lys75Gln, Lys75Ser, and Lys75Glu) indicate that all the mutated proteins folded properly and that significant protein structural rearrangements did not occur. Steady-state kinetic parameters for these FNR mutants, utilizing the diaphorase activity with DCPIP, indicate that Lys75 is not a critical residue for complex formation and electron transfer (ET) between FNR and NADP+ or NADPH. However, steady-state kinetic activities requiring complex formation and ET between FNR and Fd or Fld were appreciably affected when the positive charge at position of Lys75 was removed, and the ET reaction was not even measurable if a negatively charged residue was placed at this position. These kinetic parameters also suggest that it is complex formation that is affected by mutation. Consistent with this, when dissociation constants (Kd) for FNRox-Fdox (differential spectroscopy) and FNRox-Fdrd (laser flash photolysis) were measured, it was found that neutralization of the positive charge at position 75 increased the Kd values by 50-100-fold, and that no complex formation could be detected upon introduction of a negative charge at this position. Fast transient kinetic studies also corroborated the fact that removal of the positive charge at position 75 of FNR appreciably affects the complex formation process with its protein partners but indicates that ET is still achieved in all the reactions. This study thus clearly establishes the requirement of a positive charge at position Lys75 for complex formation during ET between FNR and its physiological protein partners. The results also suggest that the interaction of this residue with its protein partners is not structurally specific, since Lys75 can still be efficiently substituted by an arginine, but is definitely charge specific.

Iron-sulfur cluster cysteine-to-serine mutants of Anabaena -2Fe-2S- ferredoxin exhibit unexpected redox properties and are competent in electron transfer to ferredoxin:NADP+ reductase.

The reduction potentials and the rate constants for electron transfer (et) to ferredoxin:NADP+ reductase (FNR) are reported for site-directed mutants of the [2Fe-2S] vegetative cell ferredoxin (Fd) from Anabaena PCC 7120, each of which has a cluster ligating cysteine residue mutated to serine (C41S, C46S, and C49S). The X-ray crystal structure of the C49S mutant has also been determined. The UV-visible optical and CD spectra of the mutants differ from each other and from wild-type (wt) Fd. This is a consequence of oxygen replacing one of the ligating cysteine sulfur atoms, thus altering the ligand --> Fe charge transfer transition energies and the chiro-optical properties of the chromophore. Each mutant is able to rapidly accept an electron from deazariboflavin semiquinone (dRfH.) and to transfer an electron from its reduced form to oxidized FNR although all are somewhat less reactive (30-50%) toward FNR and are appreciably less stable in solution than is wt Fd. Whereas the reduction potential of C46S (-381 mV) is not significantly altered from that of wt Fd (-384 mV), the potential of the C49S mutant (-329 mV) is shifted positively by 55 mV, demonstrating that the cluster potential is sensitive to mutations made at the ferric iron in reduced [2Fe-2S] Fds with localized valences. Despite the decrease in thermodynamic driving force for et from C49S to FNR, the et rate constant is similar to that measured for C46S. Thus, the et reactivity of the mutants does not correlate with altered reduction potentials. The et rate constants of the mutants also do not correlate with the apparent binding constants of the intermediate (Fdred:FNRox) complexes or with the ability of the prosthetic group to be reduced by dRfH.. Furthermore, the X-ray crystal structure of the C49S mutant is virtually identical to that of wt Fd. We conclude from these data that cysteine sulfur d-orbitals are not essential for et into or out of the iron atoms of the cluster and that the decreased et reactivity of these Fd mutants toward FNR may be due to small changes in the mutual orientation of the proteins within the intermediate complex and/or alterations in the electronic structure of the [2Fe-2S] cluster.

Bacterial infections in suspected cutaneous leishmaniasis lesions.

In Iran, microscopic examination of skin scrapings from 2202 individuals with clinically diagnosed cutaneous leishmaniasis (CL) lesions revealed the presence of amastigotes in 1123 cases (51.0%). Bacteriological examinations of the lesions indicated that 788 individuals (35.7%) were also infected with one or more pathogenic bacteria, including coagulase-positive staphylococci (27.8%), beta-haemolytic streptococci (10.6%), and other opportunist pathogenic bacteria (total, 2.5%). The prevalence of bacterial infections in lesions in which leishmania parasites were detected was 26.5%, while for lesions in which no parasite was found the prevalence of such infections was significantly greater (45%). The results of this study show that bacterial infections should be considered in diagnosing and treating suspected CL lesions, particularly in areas where there is no facility for carrying out bacteriological examinations. Erythromycin can be used to treat the bacterial infections of the purulent sores.

Bacterial infections in suspected cutaneous leshmaniasis lesions

In Iran, microscopic examination of skin scrapings from 2202 individuals with clinically diagnosed cutanesous leishmaniasis (CL) lesions revealed the presence of amastigotes in 1123 cases (51.0 percent)

Bacteriological examinations of the lesions indicated that 788 individuals (35.7 percent) were also infected with one or more pathogenic bacteria, including coagulase-positive staphylococci (27.8 percent), betahaemolytic streptococci (10.6 percent), and other opportunist pathogenic bacteria (total 2.5 percent)

The prevalence of bacterial infections in lesions in which leishmania parasites were detected was 26.5 percent, while for lesions in which no parasite was found the prevalence of such infections was significantly greater (45 percent)

The results of this study show that bacterial infections should be considered in diagnosing and treating suspected CL lesions, particularly in areas where there is no facility for carrying out bacteriological examinations. Erythromycin can be used to treat the bacterial infections of the purulent sores