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PURPOSES: Knowledge of visual analog scale (VAS) pain assessment for transoral endoscopic thyroidectomy vestibular approach (TOETVA) is limited. The purpose of this analysis was to classify the postoperative discomfort scores in patients undergoing TOETVA compared to open thyroidectomy. METHODS: Observational clinical study of patients who underwent thyroidectomy by VAS pain assessment from September 2016 to March 2017. Patients were stratified into two groups: patients eligible for TOETVA (Group TOETVA) and non-candidates for endoscopic intervention (open thyroidectomy approach-OTA). VAS was recorded in the recovery room, at 24 h, + 2, + 5, + 15, + 30, + 90 days, and 6 months after surgery. Pain assessment was stratified in VAS-lower lip, VAS-chin, VAS-jaw, VAS-anterior neck, VAS-cervical/back, VAS-swallowing, VAS-brushing, VAS-speaking, and VAS-shaving. Secondary outcome assessed were analgesic rescue dose, morbidity, operative notes, hospital stay, and histopathology. RESULTS: 41 TOETVA and 45 OTA constituted the analysis. There were differences between the TOETVA and OTA for age, gland volume, mean nodule diameter, coexistence thyroiditis, bilateral procedures, and use of drain. Operative time was longer in TOETVA. Results indicated that TOETVA was associated with reduced neck, cervical back, and swallowing VAS scores in the 24 h after surgery. Conversely, jaw and brushing teeth resulted in higher VAS score in TOETVA group. OTA patients never experienced lower lip or chin pain. The use of rescue analgesics did not differ between the two groups. CONCLUSIONS: VAS was used to measure treatment outcome in TOETVA. VAS scores achieved overall a minimal clinical importance difference from the two procedures. There appears to be both a short- and long-term different range of interpretations of pain between TOETVA and OTA.

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Amphiphilic cyclodextrins (aCDs) are an intriguing class of carrier systems which, recently, have been proposed to deliver porphyrinoids and anticancer drugs or combined dose of both for dual therapeutic applications. The design of nanoassemblies based on aCD and photosensitizers (PSs) aims to preserve the photodynamic therapy (PDT) efficacy of PS, reducing the tendency of PS to self-aggregate, without affecting the quantum yield of singlet oxygen (1O2) production, and, not less importantly, minimizing dark toxicity and reducing photosensitization effects. With this idea in mind, in this paper, we focus on nanoassemblies between a non-ionic aCD (SC6OH) and halo-alkyl tailored iodinated boron-dipyrromethenes (BODIPY) dye, a class of molecules which recently have been successfully proposed as a stimulating alternative to porphyrinoids for their high photodynamic efficacy. Nanoassemblies of BODIPY/aCD (BL01I@SC6OH) were prepared in different aqueous media by evaporation of mixed organic film of aCD and BODIPY, hydration, and sonication. The nanostructures were characterized, measuring their hydrodynamic diameter and ξ-potential and also evaluating their time-stability in biological relevant media. Taking advantage of emissive properties of the not-iodinated BODIPY analogue (BL01), nanoassemblies based on aCD and BL01 were investigated as model system to get insight on entanglement of BODIPY in the amphiphile in aqueous dispersion, pointing out that BODIPY is well-entrapped in monomeric form (τ ≅ 6.5 ns) within the colloidal carriers. Also morphology and fluorescence emission properties were elucidated after casting the solution on glass. BL01@SC6OH is easily detectable in cytoplasm of HCT116 cell lines, evidencing the remarkable intracellular penetration of this nanoassembly similar to free BODIPY. On the same cell lines, the photodynamically active assembly BL01I/aCD shows toxicity upon irradiation. Despite the fact that free BL01I is more PDT active than its assembly, aCD can modulate the cell uptake of BODIPY, pointing out the potential of this system for in vivo PDT application.

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BACKGROUND: Although standard instrumentation is the procedure most frequently used to implant a Total Knee Arthroplasty (TKA), high rates of malalignment of tibial component are reported using this technique. Anatomical landmarks for sagittal alignment have been little investigated and the best reference axis, which parallels the mechanical axis, is yet to be established. HYPOTHESIS: Mapping the Anterior Tibial Profile (ATP) may allow the identification of segmental zones of the ATP parallel to the mechanical axis which can be used to align the extramedullary rod. METHODS: An intramedullary rod was positioned in line with the mechanical axis in 47 dried cadaveric tibiae. The rod was connected to a cutting jig and to an extramedullary rod. Digitalized images of lateral view radiographs were taken and the distance between the ATP and the extramedullary rod was measured at 10-mm intervals and at interpolated distances corresponding to every 2% of the tibial length. RESULTS: Segmental portions of the ATP exhibit an alignment parallel to the mechanical axis between points located at 58% and 90% and at 62% and 88% of the tibial length. Points placed at 50% of tibial length and 5mm proximal to the ankle joint generate the longer axis parallel to the mechanical axis. CONCLUSION: The orientation of sagittal tibial cut may be improved by aligning the extramedullary rod parallel to the ATP at definite points. Points placed at 50% of the tibial length and 5mm proximal to the ankle joint may be preferred since they generate the longer axis parallel to the mechanical axis and are more easily identified at surgery.

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Changes in body water elicit reflex adjustments at the kidney, thus maintaining fluid volume homeostasis. These renal adjustments change the concentration and color of urine, variables that can, in turn, be used as biomarkers of hydration status. It has been suggested that vitamin supplementation alters urine color; it is unclear whether any such alteration would confound hydration assessment via colorimetric evaluation. We tested the hypothesis that overnight vitamin B2 and/or B12 supplementation alters urine color as a marker of hydration status. Thirty healthy volunteers were monitored during a 3-day euhydrated baseline, confirmed via first morning nude body mass, urine specific gravity, and urine osmolality. Volunteers then randomly received B2 (n = 10), B12 (n = 10), or B2 + B12 (n = 10) at ∼200 × recommended dietary allowance. Euhydration was verified on trial days (two of the following: body mass ± 1.0% of the mean of visits 1-3, urine specific gravity < 1.02, urine osmolality < 700 mmol/kg). Vitamin purity and urinary B2 concentration ([B2]) and [B12] were quantified via ultraperformance liquid chromatography. Two independent observers assessed urine color using an eight-point standardized color chart. Following supplementation, urinary [B2] was elevated; however, urine color was not different between nonsupplemented and supplemented trials. For example, in the B2 trial, urinary [B2] increased from 8.6 × 10(4) ± 7.7 × 10(4) to 5.7 × 10(6) ± 5.3 × 10(6) nmol/l (P < 0.05), and urine color went from 4 ± 1 to 5 ± 1 (P > 0.05). Both conditions met the euhydrated color classification. We conclude that a large overnight dose of vitamins B2 and B12 does not confound assessment of euhydrated status via urine color.

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BODIPYs are versatile dyes never tested before in photodynamic application against prokaryotes. We specifically synthesized two cationic BODIPYs (compounds 3 and 4) with structural features suitable for this pourpose. The novel BODIPYs are both characterized by the presence of one pyridinium cationic group on position 8 and two iodine atoms on 2,6-positions of the dipyrrolylmethene structure, thus ensuring solubility in 1/1 water/organic solvent mixture and a good singlet oxygen formation rate. These two photosensitizers differ only in the moiety linked on pyridine nitrogen atom as 3 and 4 bear a methyl and a benzyl group, respectively. BODIPYs 3 and 4 were tested against two bacterial model strains, the Gram positive Staphylococcus xylosus and the Gram negative Escherichia coli. Despite the small structural modification between 3 and 4, a remarkable difference in photocatalyzed efficacy against the model microorganisms was observed. In particular methylated compound 3 was found much more efficient with respect to the benzylated one (4). As consequence, in-depth examination of the antibacterial activity was performed using the more efficient compound 3. A high degree of phototoxicity (>6 log units) was observed with the photosensitizer 0.5 µM against S. xylosus and 5.0 µM against E. coli, following 5 min irradiation with a green LED device (light dose 1.38 J/cm(2)). No dark toxicity was observed up to 40 µM. Further studies indicate that the phototoxic efficacy induced by BODIPY 3 depends both on its concentration and on light dose, which can be specifically modulated to achieve the eradication of the tester strains.

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OBJECTIVE: Cardiac catheterization (CC) is a life-threatening procedure in adult patients. Complicated by idiopathic arterial pulmonary hypertension (IPAH), there is a potential risk of central nervous system (CNS) damage. We measured serum levels of a well-established brain damage marker, namely S100B, collected before, during and after CC in adult patients in whom the nitric oxide (NO) test had been performed. MATERIAL AND METHODS: In 12 adult patients who had undergone CC for IPAH diagnosis, we recorded clinical and standard monitoring procedures (laboratory variables and echocardiographic patterns) and serum concentrations of S100B before (time 0), during (time 1) and after the NO test (time 2) and at 24 h after (time 3) the procedure in samples obtained from the systemic and pulmonary circulation. Patients were subdivided into NO test responders (n=6) and non-responders (n=6). Neurological evaluation was performed at admission and at discharge from hospital. RESULTS: Adult patients subjected to CC showed no overt neurological injury at discharge from hospital. No significant differences (p > 0.05 for all) in S100B serum levels between groups at times 0, 1 and 3 have been shown independently from the sampling site. It was noteworthy that the concentration of protein in the responders group at time 2 was significantly decreased (p < 0.05, for all) compared to the responder group and to baseline values. A significant correlation was found between arterial oxygen partial pressure and individual S100B concentration in the pulmonary and systemic bloodstream in the entire study group (R = -0.66 and R = 0.71, respectively; p < 0.05, for both). CONCLUSIONS: The data suggest that S100B protein assessment, as well as the NO test, may be useful when monitoring possible CNS damage during CC in patients with IPAH, and may also be valuable in relation to brain functions, especially when performed as an emergency procedure in severely hypoxic patients.

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Antecedentes y Objetivos: La metastasectomía pulmonar es un procedimiento aceptado para tratamiento de lsa metástasis (Mts) pulmonares del carcinoma colorrectal. Los pacientes no tratados presentan supervivencia a 5 años por debajo del 5%. No existe actualmente quimioterapia efectiva. Se relata en la bibliografía internacional una supervivencia actuarial de 20-40% con carciroma colorrectal con/sin resección previa de secundarismo hepático. Lugar de aplicación: Hospital privado universitario. Diseño: Modelo retrospectivo. Método: Se analizan 40 pacientes, estudiándose la supervivencia según diferentes criterios. La metastasectomía fue indicada en casos de: tumor primario controlado, ausencia de Mts extratorácicas y condición clínica favorable. Se incluyeron sólo los pacientes con resección completa de las Mts. Todos ellos fueron evaluados previamente para recidiva local o compromiso sistémico del cáncer primario. Resultados: La supervivencia actuarial a 5 años de toda la población desde la metastasectomía pulmonar fue 37,9%. Factores como: edad, sexo, tamaño y número de metástasis, intervalo libre de enfermedad, metastesectomía hepática previa y nivel preoperatorio de CEA no influyeron significatimente en los resultados. Conclusión: Una bien seleccionada población de pacientes con Mts pulmonares de carcinoma colorrectal de beneficia claramente con la resección quirúrgica de las mismas por toracotomía.

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Donald Winnicott (1896-1971), specialist in children's diseases, psychology and psychotherapy, tried to put together his experience in all these fields. His theories can be put between the orthodox psychoanalytic thought and a "relational" paediatrics. He made his research on the "global reality" of child rather than being interested in the "internal objects". Both the orthodox analysts, who condemned his theories, and the specialists in children's diseases, who didn't recognize the scientific aspect of his genius, criticised and opposed Winnicott. Even if sometimes his theories have not an organic unity, they are the result of very detailed clinical observations, which are supported by a large experience with children at the Paddington Green Children Hospital and the Queen's Hospital for Children in London. With "transition", Winnicott means an intermediate development area between the psychic and external reality. There, we can find the "transitional object", which is the first element leading the child to face the external reality through the creation of symbols. Winnicott goes over the idea of the binomial mother-child, intended as instinctive development, and underlining the importance of real experiences. In his opinion, in the child development one has to stress the concept of "need" instead of that of "desire". A good environment and the empathic contact with "a fairly good mother", cause the passage from the primary narcissism to the object relationships. A fairly good mother must be able to perform holding, handling, and object presenting. Her duty is that of gradually undeceiving, and to do it she must give a sufficient opportunity of illusion. The mother, offering the right opportunity of illusion, puts the basis of symbols. Subsequently, she will go on a gradual disillusion. Winnicott disagrees Klein's ideas by stating that "playing is therapeutic in its own aspect", seeing it as a potential space between mother and child, which will become the place of analysis and transfer and, after on, that of cultural experience.

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Turner's syndrome is generally characterised by bilateral gonadal disgenesis, short stature and inadequate sexual development secondary to anomalous karyotype. The purely otorhinolaryngoiatric pathology considerably influences the symptomatological features in Turner's subject and this is based on possible morphologically structured anomalies in the external, middle and inner ear, but also on the oral cavity and pharynx. From this there is evidence of otological emergence on a phlogistic infectious basis with remarkable long-term repercussion on the hearing process. Otofunctional evaluation in 21 Turner's syndrome patients shows predominance of conductive hearing loss (42.8%), proven through evidence of otitis media (33.3%) and chronic otitis media (9.5%). This, therefore, demands an attentive audiologic monitoring related to the possible development of chronic forms or cholesteatoma and the possible rehabilitative-prothesis procedure.

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In this study, devitalized meniscal tissue pre-seeded with viable cultured chondrocytes was used to repair a bucket-handle incision in meniscal tissue transplanted to nude mice. Lamb knee menisci were devitalized by cyclic freezing and thawing. Chips measuring four by two by one-half millimeters were cut from this devitalized tissue to serve as scaffolds. These chips were then cultured either with or without viable allogeneic lamb chondrocytes. From the inner third of the devitalized meniscal tissue, rectangles were also cut approximately 8 x 6 mm. A 4 mm bucket-handle type incision was made in these blocks. The previously prepared chips either with (experimental group) or without viable chondrocytes (control group) were positioned into the incisions and secured with suture. Further control groups included blocks of devitalized menisci with incisions into which no chips were positioned and either closed with suture or left open with no suture. Specimens were transplanted to subcutaneous pouches of nude mice for 14 weeks. After 14 weeks, seven of eight experimental specimens (chips with viable chondrocytes) demonstrated bridging of the incision assessed by gross inspection and manual distraction. All the control groups were markedly different from the experimental group in that the incision remained grossly visible. Histological analysis was consistent with the differences apparent at the gross level. Only the experimental specimens (chips with viable chondrocytes) with gross bridging demonstrated obliteration of the interface between incision and scaffold. None of the control specimens revealed any cells or tissue filling the incision. Tissue engineering using scaffolds and viable cells may have an application in meniscal repair in vivo.

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El trasplante de matrices alogenicas desvitalizadas portadoras de condrocitos autologos, previamente aislados y sembrados sobre ellas, podria ser una solucion al problema de la reparacion de las lesiones del cartilago articular. El presente estudio analiza la actividad mitotica de los condrocitos sembrados en cartilago alogenico desvitalizado e implantados en animales vivos. Se aislaron enzimaticamente condrocitos de cartilago articular de cordero, y se sembraron "in vitro" sobre matriz cartilaginosa alogenica desvitalizada durante 3 semanas. Al final del periodo de cocultivo, se trasplantaron los compuestos de matriz y condrocitos en bolsillos subcutaneos de ratones atimicos. Las muestras experimentales y las de control fueron evaluadas luego de extraidas mediante el estudio histologico y tras la incorporacion de timidina tritiada. Los resultados obtenidos mostraron una disminucion importante de los valores de incorporacion de timidina a partir del tiempo experimental cero (evaluacion preimplante) hasta el dia 28 del implante, seguido por un leve aumento hacia el dia 42 del estudio. La experiencia ha demostrado la tendencia de los condrocitos articulares (cultivados "in vitro" y sucesivamente trasplantados "in vivo" sobre un soporte de matriz cartilaginosa alogenica desvitalizada) de modificar su propia actividad mitotica desde valores muy altos, correspondiendo a los primeros dias experimentales (tipico de las fases "in vitro" de expansion celular) hasta valores muy bajos, similares a la conducta de los condrocitos articulares "in vivo"

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The transplantation of devitalized allogenic matrices vehiculating autologous chondrocytes, previously isoled and seeded on them could be a solution to the problem of repairing lesions of the joint cartilage. For the matrix/cell "composite" to be "graftable" the cells must continue to duplicate and produce cartilaginous matrix even after transport in vivo. The present study analyzes the mitotic activity of chondrocytes planted on devitalized allogenic cartilage and grafted in living animals. Chondrocytes of joint cartilage of lambs were isolated enzymatically and then seeded in vitro on devitalized allogenic cartilaginous matrices for 3 weeks. At the end of the co-culture period, these matrix/chondrocyte composites were transplanted in subcutaneous pockets of athymic mice. The experimental and control samples were evaluated subsequent to explantation by histological study and incorporation of tritiated thymidine. The results obtained revealed an important decrease in the values for the incorporation of thymidine beginning from experimental time 0 (pre-implant evaluation) up to day 28 after implantation, followed by a mild increase at the experimental time of 42 days. This study demonstrated the tendency of articular chondrocytes cultivated in vitro and subsequently transplanted in vivo on a support of devitalized allogenic cartilaginous matrix to modify mitotic activity from very high values for the first experimental times, typical of the in vitro phases of cellular expansion, to very low values, more similar to the behavior of articular chondrocytes in vivo.

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El trasplante de matrices alogenicas desvitalizadas portadoras de condrocitos autologos, previamente aislados y sembrados sobre ellas, podria ser una solucion al problema de la reparacion de las lesiones del cartilago articular. El presente estudio analiza la actividad mitotica de los condrocitos sembrados en cartilago alogenico desvitalizado e implantados en animales vivos. Se aislaron enzimaticamente condrocitos de cartilago articular de cordero, y se sembraron "in vitro" sobre matriz cartilaginosa alogenica desvitalizada durante 3 semanas. Al final del periodo de cocultivo, se trasplantaron los compuestos de matriz y condrocitos en bolsillos subcutaneos de ratones atimicos. Las muestras experimentales y las de control fueron evaluadas luego de extraidas mediante el estudio histologico y tras la incorporacion de timidina tritiada. Los resultados obtenidos mostraron una disminucion importante de los valores de incorporacion de timidina a partir del tiempo experimental cero (evaluacion preimplante) hasta el dia 28 del implante, seguido por un leve aumento hacia el dia 42 del estudio. La experiencia ha demostrado la tendencia de los condrocitos articulares (cultivados "in vitro" y sucesivamente trasplantados "in vivo" sobre un soporte de matriz cartilaginosa alogenica desvitalizada) de modificar su propia actividad mitotica desde valores muy altos, correspondiendo a los primeros dias experimentales (tipico de las fases "in vitro" de expansion celular) hasta valores muy bajos, similares a la conducta de los condrocitos articulares "in vivo"

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The objective of this study was to evaluate the biomechanical properties of newly formed cartilaginous tissue synthesized from isolated chondrocytes. Cartilage from articular joints of lambs was either digested in collagenase to isolated chondrocytes or cut into discs that were devitalized by multiple freeze-thaw cycles. Isolated cells were incubated in suspension culture in the presence of devitalized cartilage matrix for 3 weeks. Multiple chondrocyte/matrix constructs were assembled with fibrin glue and implanted subcutaneously in nude mice for up to 6 weeks. Testing methods were devised to quantify integration of cartilage pieces and mechanical properties of constructs. These studies showed monotonic increase with time in tensile strength, fracture strain, fracture energy, and tensile modulus to values 5-10% of normal articular cartilage by 6 weeks in vivo. Histological analysis indicated that chondrocytes grown on dead cartilage matrix produced new matrix that integrated individual cartilage pieces with mechanically functional tissue.

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Introducción: los timomas constituyen neoplasias infrecuentes, de presentación variada ya sea por manifestaciones locales o síndromes inmunológicos complejos. Material y métodos: se revisaron los registros de pacientes con timomas entre 1980/1997. Se analizaron datos clínicos, quirúrgicos, complicaciones, evolución y sobrevida. Resultados: cuarenta y tres pacientes con tumores tímicos ( Timomas 28). Edad X 52,3 años, 17 mujeres. Trece pacientes asintomáticos (46,4 por ciento), 15 restantes: Mistenia Gravis (MG) en 8 casos (28,5 por ciento), dolor 5, disnea 2, otros 1. Todos con radiografía de tórax anormal ( bordes netos fue el patrón predominante). Punción con aguja fina diagnosticó 7/8 casos: el resto del diagnóstico fue de sospecha. Todos intervenidos quirúrgicamente, frecuentemente por esternotomía vertical (57 por ciento). En 21 pacientes con resección simple (75 por ciento), el resto ampliada. La histología más frecuente: linfoepitelial 13 casos (46,4 por ciento). Peso y tamaño promedio de piezas: 9,9 cm y 298 gr (r 4,5 a 24 cm y 33 gr a 900 gr). Doce casos estadío I (EI) (42,9 por ciento), 9 E II (32,1 por ciento) y 7 E III y IV (25 por ciento). No se correlacionaron tamaño y peso con MG ni invasión. Tampoco entre E y MG. Todos requirieron intubación orotraqueal durante cirugía, y 11 asistidos respiratoriamente luego (ARM) (39,3 por ciento). Tiempo promedio de ARM de 6.3 días, mayor en pac. con MG (6,6 días vs 0,8 días) p<0,05. Dos fallecieron en post-operatorio inmediato en ARM con MG y tres posteriormente ( progresión tumoral, MG, y tromboembolismo pulmonar). Trece efectuaron radioterapia y 3 quimioterapia. Del total de pacientes fallecidos tres tenían MG, siendo el grupo con mayor mortalidad (37,5 por ciento vs 10 por ciento). La sobrevida global a 5 años fue 73 por ciento. Conclusiones: el timoma es una patología infrecuente. Su lento crecimiento explicaría el tamaño que alcanzan. No existió correlación entre grado de invasión con peso, tamaño, ni con presencia de MG. El tiempo de ARM y la mortalidad fue mayor en aquéllos con MG

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Introducción: los timomas constituyen neoplasias infrecuentes, de presentación variada ya sea por manifestaciones locales o síndromes inmunológicos complejos. Material y métodos: se revisaron los registros de pacientes con timomas entre 1980/1997. Se analizaron datos clínicos, quirúrgicos, complicaciones, evolución y sobrevida. Resultados: cuarenta y tres pacientes con tumores tímicos ( Timomas 28). Edad X 52,3 años, 17 mujeres. Trece pacientes asintomáticos (46,4 por ciento), 15 restantes: Mistenia Gravis (MG) en 8 casos (28,5 por ciento), dolor 5, disnea 2, otros 1. Todos con radiografía de tórax anormal ( bordes netos fue el patrón predominante). Punción con aguja fina diagnosticó 7/8 casos: el resto del diagnóstico fue de sospecha. Todos intervenidos quirúrgicamente, frecuentemente por esternotomía vertical (57 por ciento). En 21 pacientes con resección simple (75 por ciento), el resto ampliada. La histología más frecuente: linfoepitelial 13 casos (46,4 por ciento). Peso y tamaño promedio de piezas: 9,9 cm y 298 gr (r 4,5 a 24 cm y 33 gr a 900 gr). Doce casos estadío I (EI) (42,9 por ciento), 9 E II (32,1 por ciento) y 7 E III y IV (25 por ciento). No se correlacionaron tamaño y peso con MG ni invasión. Tampoco entre E y MG. Todos requirieron intubación orotraqueal durante cirugía, y 11 asistidos respiratoriamente luego (ARM) (39,3 por ciento). Tiempo promedio de ARM de 6.3 días, mayor en pac. con MG (6,6 días vs 0,8 días) p<0,05. Dos fallecieron en post-operatorio inmediato en ARM con MG y tres posteriormente ( progresión tumoral, MG, y tromboembolismo pulmonar). Trece efectuaron radioterapia y 3 quimioterapia. Del total de pacientes fallecidos tres tenían MG, siendo el grupo con mayor mortalidad (37,5 por ciento vs 10 por ciento). La sobrevida global a 5 años fue 73 por ciento. Conclusiones: el timoma es una patología infrecuente. Su lento crecimiento explicaría el tamaño que alcanzan. No existió correlación entre grado de invasión con peso, tamaño, ni con presencia de MG. El tiempo de ARM y la mortalidad fue mayor en aquéllos con MG (AU)

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A number of proteins have recently been identified which play roles in regulating bone development. One important example is Indian hedgehog (Ihh) which is secreted by the prehyprtrophic chondrocytes. Ihh acts as an activator of a second secreted factor, parathyroid hormone-related protein (PTHrP), which, in turn, negatively regulates the rate of chondrocyte differentiation. Here we examine the expression of these genes and their molecular targets during different stages of bone development. In addition to regulating PTHrP expression in the perichondrium, we find evidence that Ihh may also act on the chondrocytes themselves at particular stages. As bone growth continues postnatally in mammals and the developmental process is reactivated during fracture repair, understanding the molecular basis regulating bone development is of medical relevance. We find that the same molecules that regulate embryonic endochondral ossification are also expressed during postnatal bone growth and fracture healing, suggesting that these processes are controlled by similar mechanisms.

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The capacity of isolated chondrocytes to join separate masses of cartilage matrix was investigated with composites implanted in subcutaneous pouches in nude mice. Slices of articular cartilage were harvested from lambs and were devitalized by cyclic freezing and thawing. The slices were then either co-cultured with viable allogeneic lamb chondrocytes (experimental) or cultured without such chondrocytes (control). Composites of three slices were constructed with use of fibrin glue and were implanted in nude mice for periods ranging from 7 to 42 days. Bonding of the experimental matrices with viable chondrocytes was achieved at 28 and 42 days, as assessed by direct examination, histology, thymidine uptake, and fluorescence. No bonding occurred in the control composites without viable chondrocytes. We conclude that devitalized cartilage matrix is a scaffold to which isolated chondrocytes can attach and begin to repopulate.

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Growth of chondrocytes into a xenogeneic chondroepiphyseal matrix was investigated in an in vitro experimental model by combining viable calf chondrocytes with chick epiphyseal matrix devoid of viable chondrocytes. The chondrocytes were harvested from the wrist joints of newborn calves and cultured for 2 days. The epiphyses were harvested from the distal femurs and the proximal tibias of fetal chicks after development was arrested at 17 days by freezing. The epiphyseal specimens were prepared in four ways. These included femoral and tibial epiphyses without holes and femoral and tibial epiphyses with holes made by a laser. These epiphyseal specimens were co-cultured with calf chondrocytes for various periods. After digestion of the epiphyseal matrix, viable chondrocytes were counted in suspension. Chondrocyte division in the matrix was assessed by [3H]thymidine incorporation. The growth of calf chondrocytes into the xenogeneic chick matrix was evaluated by fluorescence microscopy on fresh thick epiphyseal sections. The percentage of viable chondrocytes in the xenogeneic epiphyseal matrix increased with culture time to a maximum at day 21. The addition of laser-drilled holes was found to extend a plateau of chondrocyte viability until day 29. A decrease in cell viability was detected at later observation points. This study demonstrates that xenogeneic matrix may serve as a morphogenetic scaffold for chondrocytic growth.

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This article identifies the components necessary for comprehensive dermatologic assessment, including the pertinent anatomy and physiology, appropriate health history, and physical examination strategies. An overview of common dermatologic conditions in women is presented, and the identification of and action needed for life-threatening dermatologic conditions are reviewed. This article is the first of two articles on primary care for women with dermatological complaints; the subsequent article will address primary care management of common dermatologic conditions.

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