The kinetic parameters and energy cost of the Hsp70 chaperone as a polypeptide unfoldase.

Hsp70-Hsp40-NEF and possibly Hsp100 are the only known molecular chaperones that can use the energy of ATP to convert stably pre-aggregated polypeptides into natively refolded proteins. However, the kinetic parameters and ATP costs have remained elusive because refolding reactions have only been successful with a molar excess of chaperones over their polypeptide substrates. Here we describe a stable, misfolded luciferase species that can be efficiently renatured by substoichiometric amounts of bacterial Hsp70-Hsp40-NEF. The reactivation rates increased with substrate concentration and followed saturation kinetics, thus allowing the determination of apparent V(max)' and K(m)' values for a chaperone-mediated renaturation reaction for the first time. Under the in vitro conditions used, one Hsp70 molecule consumed five ATPs to effectively unfold a single misfolded protein into an intermediate that, upon chaperone dissociation, spontaneously refolded to the native state, a process with an ATP cost a thousand times lower than expected for protein degradation and resynthesis.

Tracing of the Rhône River, wastewater, and mixing within Lake Geneva : stable isotope compositions of water and dissolved inorganic carbon

This study presents an evaluation of the stable isotopic composition of water (hydrogen and oxygen) and dissolved inorganic carbon (DIC) of Lake Geneva, a deep, peri-alpine lake situated at the border between Switzerland and France. The research goal is to apply vertical and seasonal variations of the isotope compositions to evaluate mixing processes of pollutants, nutrients and oxygen. Depth profiles were sampled at different locations throughout Lake Geneva on a monthly and seasonal basis over the course of three years (2009-2011). The results of the oxygen isotopic composition indicate a Rhône River interflow, which can be traced for about 55 km throughout the lake during summer. The Rhône River interflow is 7 to 15 m thick and the molar fraction of Rhône water is estimated to amount up to 37 %. Calculated density of the water and measured isotopic compositions demonstrate that the interflow depth changes in conjunction with the density gradient in the water column during fall. Partial pressure of CO2 indicates that the epilimnion is taking up CO2 from the atmosphere between spring and fall. The epilimnion is most enriched in 13CDIC in September and a progressive depletion of 13CDIC can be observed in the metalimnion from spring to late fall. This stratification is dependent on the local density stratification and the results demonstrate that parameters, which are indicating photosynthesis, are not necessarily linked to δ13CDIC values. In addition, the amount of primary production shows a strong discrepancy between summer 2009 and 2010, but δ13CDIC values of the epilimnion and metalimnion do not indicate variations. In the hypolimnion of the deep lake δ13CDIC values are constant and the progressive depletion allows tracing remineralization processes. The combination of stable carbon and oxygen isotopic compositions allows furthermore tracing Rhône River water fractions, as well as wastewater, stormwater and anthropogenic induced carbon in the water column of the shallow Bay of Vidy. In combination with the results of measured micropollutants, the study underlines that concentrations of certain substances may be related to the Rhône River interflow and/or remineralization of particulate organic carbon. Water quality monitoring and research should therefore be extended to the metalimnion as well as sediment water interface.

Retentiopolymeerin optimointi täyteaineiden yhtäaikaisannostelussa

Kirjallisuusosassa perehdyttiin retentioaineisiin ja täyteaineisiin sekä retentioaineiden ja rainanmuodostusolosuhteiden vaikutukseen retentioon, vedenpoistoon ja paperin ominaisuuksiin. Tarkemmin kirjallisuusosassa keskityttiin täyteaineiden esiflokkaukseen, retentiopolymeerin adsorptioon sekä retentiopolymeerien ja täyteaineiden annostelutapoihin. Kokeellisessa osassa tutkittiin sarjaa retentiopolymeerejä, joiden varaustiheys ja moolimassa muuttuivat. Yksi polymeereistä oli kahdesta polymeeristävalmistettu suoladispersio ja yksi modifioitu kationinen PAM. Näillä polymeereillä käytiin läpi koesarjoja, joissa muutettiin täyteaineen annosteluaikaa retentiopolymeerin annosteluajan pysyessä vakiona. Lähinnä vertailtiin keskenään perinteistä annostelua, jossa täyteaine annosteltiin paljon ennen retentiopolymeeriä,ja yhtäaikaista annostelua, jossa molemmat annosteltiin yhtä aikaa lähellä perälaatikkoa. Kokeet tehtiin MBF-laitteella, jolla pystytään paperikonetta vastaaviin pulsaatiotaajuuksiin ja sillä voidaan valmistaa tasoviirakoneella valmistetunpaperin kaltaisia laboratorioarkkeja. Valmistetuista arkeista tutkittiin retentioita ja paperiteknisiä ominaisuuksia. Laboratoriokokeiden perusteella yhtäaikainen annostelu antoi paremmat täyteaineretentiot verrattaessa perinteiseen annosteluun lähes kaikissa koesarjoissa. Varsinkin lyhytketjuiset polymeerit näyttivättoimivan hyvin yhtäaikaisannostelulla, mikä saattaisi johtua siitä, että lyhyt reagointiaika sulpun kanssa on lyhytketjuisille polymeereille edullinen, sillä silloin polymeeriketjun konformaatio ei ehdi asettua liian alhaiseksi ja ketjun toimintakyky säilyy parempana. Polymeerin varaustiheyden kasvaessa riittävästi laski täyteaineretentio seuraavissa tapauksissa: SC-massa + kaoliini ja SC-massa +GCC kummallakin annostelulla sekä SC-massa + PCC A perinteisellä annostelulla. Hienopaperimassalla samaa trendiä noudatti täyteaine GCC kummallakin annostelulla, kun taas PCC H:ta käytettäessä paranivat täyteaineretentiot molemmilla annosteluilla. Retentiopolymeerin moolimassan kasvaessa riittävästi kääntyi täyteaineretentio laskuun täyteaineilla GCC ja kaoliini, kun käytettiin SC-massaa. Hienopaperimassalla GCC noudatti tätä samaa taipumusta. Sen sijaan SC-massalla PCC A:takäytettäessä täyteaineretentio puolestaan nousi hieman moolimassan kasvaessa. Näin kävi myös hienopaperimassalla, kun täyteaineena käytettiin PCC H:ta. Käytettäessä SC-massaa, perinteisellä annostelulla saatiin parempi tai yhtä hyvä valonsironta kuin yhtäaikaisella annostelulla kaikilla täyteaineilla. Tämä saattaisi johtua siitä, että yhtäaikaisannostelulla on muodostunut suurempia täyteaineflokkeja, mikä on alentanut valoa sirottavia pintoja. Täyteaineista korkeimmat valonsirontakertoimet antoi PCC A ja alhaisimmat kaoliini. PCC A:lla oli kapein partikkelikokojakauma, mikä korottaa paperin valonsirontaa. Hienopaperimassalla valonsirontakerroin ja opasiteetti suurenivat GCC-pitoisuuden kasvaessa kummallakin annostelulla, mikä voisi johtua täyteainepartikkelien antamasta paremmasta sironnasta. Yhtäaikaisella annostelulla saavutettiin huomattavasti paremmat valonsironnan arvot perinteiseen annosteluun verrattuna. PCC H-pitoisuuden kasvaessa suurenivat myös valonsirontakerroin ja opasiteetti kummallakin annostelulla. PCC H antoi korkeammat valonsirontakertoimet kuin GCC. PCC omaa suuremman valonheijastusluvun kuin GCC, minkä vuoksi se antaa paremmat valonsirontakertoimen arvot. PCC H:n partikkelikokojakauma oli myös kapeampi kuin GCC:n, mikä mahdollisti paremman valonsironnan ja opasiteetin saavuttamisen.

Väkevän urealiuoksen puhdistaminen kalvotekniikalla

Kirjallisuusosassa käsiteltiin nanosuodatus-, käänteisosmoosi- ja elektrodialyysitekniikoita liuosten puhdistuksessa. Nanosuodatuksella ja käänteisosmoosilla voidaan liuottimesta erottaa pienen moolimassan omaavia liuenneita aineita ohuen kalvon avulla. Nanosuodatuksessa ja käänteisosmoosissa ajavana voimana on paine, jonka tulee ylittää liuoksen osmoottinen paine. Elektrodialyysissä ajavana voimana toimii sähköpotentiaaliero. Tekniikka käyttää hyväkseen ionien tai molekyylien kykyä johtaa sähköä. Elektrodialyysillä voidaan liuoksesta erottaa toisistaan varauksettomat ja varaukselliset komponentit sähköä johtavan membraanin avulla. Kokeellisessa osassa väkevää ureavesiliuosta suodatettiin nanosuodatus- ja käänteisosmoosikalvoilla tutkien paineen, lämpötilan ja konsentroitumisen vaikutusta vuohonja retentioon. Tarkoituksena oli saada urea tuotteena permeaattiin ja epäpuhtaudet erottumaan retentaattiin. Permeaattien epäpuhtauksien pitoisuuksia verrattiin tuotteen spesifikaation raja-arvoihin. Suodatukset tehtiin Lappeenrannan teknillisen yliopiston tiloissa DSS Labstak M20 suotimella. Työssä käytettiin NF1-, NF2-, NF270-, NF-, NF90-, Desal-5 DK-, OPMN-P 70- ja TFC ULP-kalvoja. Nanosuodatuskalvot NF2- ja NF270 antoivat parhaan vuon ja erotuskyvyn suhteen puhdistettaessa urealiuosta. Paineen noustessa kalvojen retentiot paranivat. Lämpötilan noustessa vuo parani, joskin täytyy huomioida urean kiihtyvä hajoaminen lähestyttäessä 40 °C astetta. Kalvojen kestävyyttä ureasuodatuksissa ei voitu näiden kokeiden avulla varmentaa.

Effect of physico-chemical conditions and operating parameters on flux and retention of different components in ultrafiltration and nanofiltration fractionation of sweet whey

Tässä väitöstutkimuksessa tutkittiin fysikaaliskemiallisten olosuhteiden ja toimintaparametrien vaikutusta juustoheran fraktiointiin. Kirjallisuusosassa on käsitelty heran ympäristövaikutusta, heran hyödyntämistä ja heran käsittelyä kalvotekniikalla. Kokeellinen osa on jaettu kahteen osaan, joista ensimmäinen käsittelee ultrasuodatusta ja toinen nanosuodatusta juustoheran fraktioinnissa. Ultrasuodatuskalvon valinta tehtiin perustuen kalvon cut-off lukuun, joka oli määritetty polyetyleeniglykoliliuoksilla olosuhteissa, joissa konsentraatiopolariosaatioei häiritse mittausta. Kriittisen vuon konseptia käytettiin sopivan proteiinikonsentraation löytämiseksi ultrasuodatuskokeisiin, koska heraproteiinit ovat tunnetusti kalvoa likaavia aineita. Ultrasuodatuskokeissa tutkittiin heran eri komponenttien suodattumista kalvon läpi ja siihen vaikuttavia ominaisuuksia. Herapermeaattien peptidifraktiot analysoitiin kokoekskluusiokromatografialla ja MALDI-TOF massaspektrometrillä. Kokeissa käytettävien nanosuodatuskalvojen keskimääräinen huokoskoko analysoitiin neutraaleilla liukoisilla aineilla ja zeta-potentiaalit virtauspotentiaalimittauksilla. Aminohappoja käytettiin malliaineina tutkittaessa huokoskoon ja varauksen merkitystä erotuksessa. Aminohappojen retentioon vaikuttivat pH ja liuoksen ionivahvuus sekä molekyylien väliset vuorovaikutukset. Heran ultrasuodatuksessa tuotettu permeaatti, joka sisälsi pieniä peptidejä, laktoosia ja suoloja, nanosuodatettiin happamassa ja emäksisessä pH:ssa. Emäksisissä oloissa tehdyssä nanosuodatuksessa foulaantumista tapahtui vähemmän ja permeaattivuo oli parempi. Emäksisissä oloissa myös selektiivisyys laktoosin erotuksessa peptideistä oli parempi verrattuna selektiivisyyteen happamissa oloissa.

A Study on Fractionation and Ultrafiltration of Proteins with Characterized Modified and Unmodified Membranes

Membrane filtration has become increasingly attractive in the processing of both foodand biotechnological products. However, the poor selectivity of the membranes and fouling are the critical factors limiting the development of UF systems for the specific fractionation of protein mixtures. This thesis gives an overview on fractionation of proteins from model protein solutions or from biological solutions. An attempt was made to improve the selectivity of the available membranes by modifying the membranes and by exploiting the different electrostatic interactions between the proteins and the membrane pore surfaces. Fractionation and UF behavior of proteins in the model solutions and in the corresponding biological solutions were compared. Characterization of the membranes and protein adsorptionto the membrane were investigated with combined flux and streaming potential studies. It has been shown that fouling of the membranes can be reduced using "self-rejecting" membranes at pH values where electrostatic repulsion is achieved between the membrane and the proteins in solution. This effect is best shown in UF of dilute single protein solutions at low ionic strengths and low pressures. Fractionation of model proteins in single, binary, and ternary solutionshas been carried out. The results have been compared to the results obtained from fractination of biological solutions. It was generally observed that fractination of proteins from biological solutions are more difficult to carry out owingto the presence of non studied protein components with different properties. Itcan be generally concluded that it is easier to enrich the smaller protein in the permeate but it is also possible to enrich the larger protein in the permeateat pH values close to the isoelectric point of the protein. It should be possible to find an optimal flux and modification to effectively improve the fractination of proteins even with very similar molar masses.

Supernumerary molars. A review of 53 cases

Supernumerary molars are not uncommon and may be found nearly anywhere in the dental alveolar arches. A series of 36 patients that presented with 53 supernumerary molars are reviewed. They occurred more frequently in the maxilla (86.8%), had little or no clinical significance, tended to be impacted, and were not associated with the impactation of the third molar. Four cases of maxillary fifth molars are described

Acylation of chiral alcohols: a simple procedure for chiral GC analysis

The use of iodine as a catalyst and either acetic or trifluoroacetic acid as a derivatizing reagent for determining the enantiomeric composition of acyclic and cyclic aliphatic chiral alcohols was investigated. Optimal conditions were selected according to the molar ratio of alcohol to acid, the reaction time, and the reaction temperature. Afterwards, chiral stability of chiral carbons was studied. Although no isomerization was observed when acetic acid was used, partial isomerization was detected with the trifluoroacetic acid. A series of chiral alcohols of a widely varying structural type were then derivatized with acetic acid using the optimal conditions. The resolution of the enantiomeric esters and the free chiral alcohols was measured using a capillary gas chromatograph equipped with a CP Chirasil-DEX CB column. The best resolutions were obtained with 2-pentyl acetates (α = 3.00) and 2-hexyl acetates (α = 1.95). This method provides a very simple and efficient experimental workup procedure for analyzing chiral alcohols by chiral-phase GC.

Erupted odontomas: a report of three cases and review of the literature

Introduction: Odontomas are benign odontogenic tumors composed of enamel, dentine, cement and pulp tissue. They are usually clinically asymptomatic, but often associated with tooth eruption disturbances. In exceptional cases the odontoma erupts into the mouth. The present study reports three cases of odontomas erupted into the oral cavity and reviews the literature. Clinical cases: The first case was an 11-year-old girl with impacted 4.6 associated to a radiopaque mass measuring about 2 cm in diameter. The histological diagnosis was complex odontoma. A clinical and radiological follow-up of 4.6 was carried out until its spontaneous eruption. The second case was a 26-year-old male presenting a hard, yellowish-brown mass located distal to the upper left second molar. Computed tomography confi rmed the presence of a radiopaque lesion, and the histopathological study confirmed a complex odontoma. The third patient was a 27-year-old male reporting tongue irritation due to tooth eruption in the inferior lingual region. A periapical radiograph revealed a mixed radiopaque lesion associated to impacted 3.2. The histological report in this case indicated a compound odontoma. Discussion: Odontomas erupting into the oral cavity are rare. The first case was published in 1980, and since then only 17 cases have been reported in the literature. Eight of the 17 cases were complex odontomas; the rest were compound odontomas. Pain, swelling and infection were the most common symptoms, and 13 cases presented an impacted tooth associated with the lesion

Morbilidad de la extracción de los terceros molares en pacientes entre los 12 y 18 años de edad

Objetivo: El propósito de este estudio fue analizar la incidencia de complicaciones después de la extracción quirúrgica de los terceros molares en pacientes de 12 a 18 años de edad. Pacientes y método: Se realizó un estudio retrospectivo de 390 extracciones quirúgicas de terceros molares superiores e inferiores en 173 pacientes en edades comprendidas entre los 12 y 18 años de edad, intervenidos bajo anestesia locorregional en el año 2000 en el Máster de Cirugía Bucal e Implantología Bucofacial de la Universidad de Barcelona. Los pacientes fueron divididos en tres grupos (A: 12-14 años, B:15-16 años, C: 17-18 años). Se registró la edad y el sexo del paciente, el motivo de la extracción, el grado de desarrollo dentario, la posición, la angulación y la inclusión del tercer molar. Finalmente se valoró la asociación entre dichas variables y la aparición de complicaciones postoperatorias. Resultados: La mayoría de los pacientes intervenidos fueron del sexo femenino (66,9%), y el grupo de edad en la que se realizó el mayor número de extracciones (62,8%) fue en el grupo C (17-18 años). El principal motivo de extracción fue la indicación por parte del ortodoncista (40,5%), seguido por la indicación profiláctica (39,5%). La presencia de clínica fue el motivo de extracción en un 20% de los casos. Se observó una incidencia del 15,6% de complicaciones postoperatorias tras la extracción de 390 terceros molares. En el grupo A el riesgo de complicaciones fue de 17,4%, en el grupo B de 19% y en el grupo C de 13,7%. Todas las complicaciones fueron reversibles y de corta duración como el dolor y la inflamación persistente, la infección, el trismo y la equimosis. Se presentó un caso de parestesia del nervio dentario inferior y un caso de parestesia del nervio lingual que remitieron a los 2 meses y al mes respectivamente. Conclusiones: este estudio demuestra que no hay diferencias significativas en las complicaciones observadas entre los tres grupos de edad, y por lo general, éstas son leves y reversibles. Se observó una mayor tendencia de complicaciones en las mujeres y el porcentaje de complicaciones aumenta cuanto menor es el espacio disponible para la erupción

Evaluation of the indication for surgical extraction of third molars according to the oral surgeon and the primary care dentist. Experience in the Master of Oral Surgery and Implantology at Barcelona University Dental School

Introduction: Third molar extraction is the most frequent procedure in oral surgery. The present study evaluates the indication of third molar extraction as established by the primary care dentist (PCD) and the oral surgeon, and compares the justification for extraction with the principal reason for patient consultation. Patients and method: A descriptive study was made of 319 patients subjected to surgical removal of a third molar in the context of the Master of Oral Surgery and Implantology (Barcelona University Dental School, Barcelona, Spain) between July 2004 and March 2005. The following parameters were evaluated: sex, age, molar, type of impaction, position according to the classifications of Pell and Gregory and of Winter, and the reasons justifying extraction. Results: The lower third molars were the most commonly extracted molars (73.7%). A total of 69.6% of the teeth were covered by soft tissues only. Fifty-six percent of the lower molars corresponded to Pell and Gregory Class IIB, while 42.1% were in the vertical position. The most common reason for patient reference to our Service of Oral Surgery on the part of the PCD was prophylactic removal (51.0% versus 46.1% in the case of the oral surgeon). Discussion and conclusions. Our results show prophylaxis to be the principal indication of third molar extraction, followed by orthodontic reasons. Regarding third molars with associated clinical symptoms or signs, infectious disease-including pericoronitis- was the pathology most often observed by the oral surgeon, followed by caries. This order of frequency was seen to invert in the case of third molars referred for extraction by the PCD. A vertical position predominated among the third molars with associated pathology

Endosseous dental implant fractures an analysis of 21 cases

Implant fracture is an infrequent cause of implant failure. The present study evaluates 21 fractured implants, with an analysis of patient age and sex, the type, length and diameter of the implant, positioning in the dental arch, the type of prosthetic rehabilitation involved, the number of abutments and pontics, the presence or absence of distal extensions or cantilevers, and loading time to fracture. Implant fracture was more common in males than in females (15:4), and the mean patient age was 56.9 years. Most cases (n = 19) corresponded to implant-supported fixed prostheses - 16 with cantilevers of different lengths- while only two fractured implants were supporting overdentures instead of fixed prostheses. The great majority of fractured implants (80.9%) were located in the molar and premolar regions, and most fractured within 3-4 years after loading. It is important to know and apply the measures required to prevent implant fracture, and to seek the best individualized solution for each case - though complete implant removal is usually the treatment of choice

Klammt's elastic open activator: Ricketts' cephalometrics results

The purpose of this study is to investigate the orthodontic and orthopaedic real effects of the Klammt's Elastic Open Activator (EOA) in 25 Class II Division 1 patients in growing period. We wanted to determine statistically the cephalometrics changes produced in the patients, comparing the lateral cranium teleradiographies we took for the diagnosis with the ones we took at the end of treatment. At the end of this study we confirm that by using the EOA we obtained the desired effects, especially reducing the molar relation 2.53 mm and the overjet 2.56 mm. The EOA corrected the inclination and protrusion of incisors, although we cannot avoid the use of fixed appliances to round off. The reduction of 2.48 mm of facial convexity stands out as the most important skeletal effect; the facial depth angle increases 0.8 degree, and the maxillary depth decreases 1.16 degrees. The length of the mandibular corpus also increases 6.7 mm, although this change is mainly due to the growth of the patient. The changes in the aesthetic profile do not stand out

False normal Lung Clearance Index in infants with cystic fibrosis due to software algorithms.

BACKGROUND: Lung clearance index (LCI), a marker of ventilation inhomogeneity, is elevated early in children with cystic fibrosis (CF). However, in infants with CF, LCI values are found to be normal, although structural lung abnormalities are often detectable. We hypothesized that this discrepancy is due to inadequate algorithms of the available software package. AIM: Our aim was to challenge the validity of these software algorithms. METHODS: We compared multiple breath washout (MBW) results of current software algorithms (automatic modus) to refined algorithms (manual modus) in 17 asymptomatic infants with CF, and 24 matched healthy term-born infants. The main difference between these two analysis methods lies in the calculation of the molar mass differences that the system uses to define the completion of the measurement. RESULTS: In infants with CF the refined manual modus revealed clearly elevated LCI above 9 in 8 out of 35 measurements (23%), all showing LCI values below 8.3 using the automatic modus (paired t-test comparing the means, P < 0.001). Healthy infants showed normal LCI values using both analysis methods (n = 47, paired t-test, P = 0.79). The most relevant reason for false normal LCI values in infants with CF using the automatic modus was the incorrect recognition of the end-of-test too early during the washout. CONCLUSION: We recommend the use of the manual modus for the analysis of MBW outcomes in infants in order to obtain more accurate results. This will allow appropriate use of infant lung function results for clinical and scientific purposes. Pediatr Pulmonol. 2015; 50:970-977. © 2015 Wiley Periodicals, Inc.