The 2019-2020 volcanic eruption of Late'iki (Metis Shoal), Tonga.

Late'iki (previously known as Metis Shoal) is a highly active volcano in the Tofua arc with at least four temporary island-building eruptions and one submarine eruption in the last 55 years. The most recent eruption, commencing in October 2019, resulted in lava effusion and subsequent phreatic explosions, the construction of a short-lived island that was quickly eroded by wave action and possibly further phreatic activity that continued into January 2020. The two-pyroxene dacite from the 2019 eruption is similar to the 1967/8 eruptions suggesting the magma is residual from earlier eruptions and has not undergone further differentiation in the last 50 years. New observations of the 2019 eruption site confirm the lava-dominant character of the volcano summit but a thin veneer of wave-reworked, finely fragmented lava material remains that is interpreted to have been produced by phreatic explosions from hot rock-water interactions during the effusive eruption. A notable absence of quench-fragmented hyaloclastite breccias suggests that non-explosive quench fragmentation processes were minimal at these shallow depths or that hyaloclastite debris has resedimented to greater depths beyond our summit survey area.

An eDNA assay for Irish Petromyzon marinus and Salmo trutta and field validation in running water.

This pilot study presents an environmental DNA (eDNA) assay for sea lamprey Petromyzon marinus and brown trout Salmo trutta, two species of economic and conservation importance in the Republic of Ireland. The results demonstrate the effectiveness of eDNA for assessing presence of low-abundance taxa (here, P. marinus) for environmental managers, and they highlight the potential for assessing relative abundance of rare or invasive freshwater species.

Initiation, maintenance, and quantification of human hematopoietic cell cultures.

The culture of hematopoietic cells for cell and gene therapies is a rapidly growing area within the field of applied hematology and tissue engineering. As evidenced by recent clinical trials (1), ex vivo expanded hematopoietic cells offer great promise for the reconstitution of in vivo hematopoiesis in immunocompromised patients who have undergone chemotherapy. Other potential applications for ex vivo expansion include production of cycling stem and progenitor cells for gene therapy, expansion of dendritic cells for immunotherapy, and production of red blood cells (RBCs) and platelets for transfusions (2).

Nuclei-size distributions as predictive tools of hematopoietic cell proliferation.

BACKGROUND: Current protocols for transplantation of hematopoietic stem and progenitor cells may be limited by donor-cell availability and the long time needed to restore neutrophil and platelet counts to normal levels. Ex vivo expansion of hematopoietic cells has the potential to decrease the required harvest size, and to enhance the transplant outcome, by providing greater numbers of progenitor and post-progenitor cells. However, widespread application of ex vivo expansion in the clinical setting is complicated by sample-to-sample variability in the extent and kinetics of cell expansion. For example, the lag time before active cell expansion may vary by several days and some samples may never expand under the culture conditions employed. An early determination regarding the fate of a culture would save time and resources, and would allow corrective action to be taken if desired. Furthermore, anticipation of the onset of cell cycling should prove useful in the development of culture-feeding strategies, as well as for maximizing transduction efficiency in gene-therapy protocols that employ retroviral vectors. METHODS: We demonstrate that the nuclei-size distribution, which is obtained at the same time as the total nucleated cell concentration, can be used to predict the onset of cell proliferation. The formation of a second peak (with diameter > 4 microm) in the nuclei-size distribution, in addition to the smaller diameter peak (< 4 microm) present for quiescent cells, precedes total cell expansion. RESULTS: In particular 94% of all MNC and CD34+ cell cultures that we have observed to exhibit a second peak in the nuclei-size distribution have realized total cell expansion. Furthermore, only one of 67 observed cultures that did not exhibit the formation of a second peak realized total cell expansion. The formation of a second peak in the nuclei-size distribution is evident, either before or on the same day as the presence of a significant fraction of cells in the S-phase of the cell cycle.

Characterization of hematopoietic cell expansion, oxygen uptake, and glycolysis in a controlled, stirred-tank bioreactor system.

Cultures of umbilical cord blood and mobilized peripheral blood mononuclear cells were carried out in a stirred bioreactor with pH and dissolved oxygen control. Expansion of total cells and colony-forming units granulocyte-macrophage was greatly enhanced by the use of a cell-dilution feeding protocol (as compared to a cell-retention feeding protocol). The specific oxygen consumption rate (qO2) for these cultures ranged from 1.7 x 10(-8) to 1.2 x 10(-7) micromol/(cell.h). The maximum in qO2 for each culture closely corresponded with the maximum percentage of progenitor or colony-forming cells (CFCs) present in the culture. The maximum qO2 values are slightly less than those reported for hybridomas, while the lowest qO2 values are somewhat greater than those reported for mature granulocytes. Examination of the ratio of lactate production to oxygen consumption in these cultures suggests that post-progenitor cells of the granulomonocytic lineage obtain a greater portion of their energy from glycolysis than do CFCs. The different metabolic profiles of CFCs and more mature cells suggest that monitoring the uptake or production of oxygen, lactate, and other metabolites will allow estimation of the content of several cell types in culture.

Stirred culture of peripheral and cord blood hematopoietic cells offers advantages over traditional static systems for clinically relevant applications.

The ability to culture hematopoietic cells in readily characterizable and scalable stirred systems, combined with the capability to utilize serum-free medium, will aid the development of clinically attractive bioreactor systems for transplantation therapies. We thus examined the proliferation and differentiation characteristics of peripheral blood (PB) mononuclear cells (MNC), cord blood (CB) MNC, and PB CD34(+) cells in spinner flasks and (control) T-flask cultures in both serum-containing and serum-free media. Hematopoietic cultures initiated from all sources examined (PB MNC, CB MNC, and PB CD34(+) cells) grew well in spinner vessels with either serum-containing or serum-free medium. Culture proliferation in spinner flasks was dependent on both agitator design and RPM as well as on the establishment of critical inoculum densities (ID) in both serum-containing (2 x 10(5) MNC/mL) and serum-free (3 x 10(5) MNC/mL) media. Spinner flask culture of PB MNC in serum-containing medium provided superior expansion of total cells and colony-forming cells (CFC) at high ID (1.2 x 10(6) cells/mL) as compared to T-flask controls. Serum-free spinner culture was comparable, if not superior, to that observed in serum-containing medium. This is the first report of stirred culture of PB or CB MNC, as well as the first report of stirred CD34(+) cell culture. Additionally, this is the first account of serum-free stirred culture of hematopoietic cells from any source.

Real-time method for determining the colony-forming cell content of human hematopoietic cell cultures.

Glucose and lactate metabolic rates were evaluated for cultures of cord blood (CB) mononuclear cell (MNC), peripheral blood (PB) MNC, and PB CD34(+) cell cultures carried out in spinner flasks and in T-flasks in both serum-containing and serum-free media. Specific glucose uptake rates (q(gluc), in micromoles per cell per hour) and lactate generation rates (q(lac)) correlated with the percentage of colony-forming cells (CFC) present in the culture for a broad range of culture conditions. Specifically, the time of maximum CFC percentage in each culture coincided with the time of maximum q(gluc) and q(lac) in cultures with different seeding densities and cytokine combinations. A two-population model (Q(lac) = alpha[CFC] + beta([TC] - [CFC ]), where [TC] is total cell concentration; Q(lac) is volumetric lactate production rate in micromoles per milliliter per hour; alpha is q(lac) for an average CFC; and beta is q(lac) for an average non-CFC) was developed to describe lactate production. The model described lactate production well for cultures carried out in both T-flasks and spinner flasks and inoculated with either PB or CB MNC or PB CD34(+) cells. The values for alpha and beta that were derived from the model varied with both the inoculum density and the cytokine combination. However, preliminary results indicate that cultures carried out under the same conditions from different samples with similar initial CD34(+) cell content have similar values for beta and beta. These findings suggest that it should be possible to use lactate production data to predict the harvest time that corresponds to the maximum number of CFC in culture. The ability to harvest ex vivo hematopoietic cultures for transplantation when CFC are at a maximum has the potential to speed the rate at which immunocompromised patients recover. (c) 1997 John Wiley & Sons, Inc. Biotechnol Bioeng 55: 693-700, 1997.

Comparison of whole serum-deprived media for ex vivo expansion of hematopoietic progenitor cells from cord blood and mobilized peripheral blood mononuclear cells.

A whole serum-deprived (WSD) medium was developed and optimized for expansion of colony-forming cells (CFC) in cord blood (CB) mononuclear cell (MNC) cultures. This medium was compared with four commercially available WSD media (commercial media), three WSD media whose compositions have been publicly disclosed (public media), two serum-containing media, and two basal media, for cell and CFC expansion in 10-day CB and mobilized peripheral blood (PB) MNC cultures supplemented with interleukin-3 (IL-3), IL-6, and stem cell factor (SCF). Selected WSD media and both serum-containing media gave significant CFC expansion in CBMNC and PBMNC cultures. The serum-containing human long-term medium gave the greatest cell (3.0-fold) and CFC (25-fold) expansions in CBMNC cultures, whereas our medium maintained the most cells (93% of input) and gave the greatest CFC expansion (6.1-fold) for PBMNC cultures. Of the commercial media, Progenitor-34 gave the greatest cell expansion (1.2-fold) and X VIVO-10 gave the greatest CFC expansion (11-fold) for CBMNC cultures, and Progenitor-34 maintained the most cells (83% of input) and gave the greatest CFC expansion (3.1-fold) for PBMNC cultures. Of the public media (including ours), our medium gave the greatest cell (1.4-fold) and CFC (6.1-fold) expansion for CBMNC cultures. Although there were slight correlations between cell and CFC expansion in 10-day CBMNC and PBMNC cultures (r2 of 0.848 and 0.594, respectively), the correlations did not give reliable predictions for medium selection. In addition, the different media favored expansion of different CFC types and performed differently for cultures using different cell sources (CB versus PB). Taken together, these results suggest that media must be carefully screened for the cell source to be cultured and the cell type(s) to be produced (e.g. total cells, CFC).

Verrucous herpes virus infection in human immunodeficiency virus patients.

OBJECTIVE: Two cases of varicella-zoster virus infection that were clinically and pathologically verrucous are reported. Although this phenomenon has previously been described in the dermatology literature, it has not, to our knowledge, been described in the pathology literature. It is important that pathologists are aware of these uncommon but histologically distinctive lesions. DATA SOURCES: The patients were seen and treated at the Departments of Dermatology of the University of Texas Health Science Center at San Antonio and Brackenridge Hospital in Austin, Tex. All information was derived from the medical records and from the attending physicians. CONCLUSIONS: Verrucous lesions of herpes (varicella) zoster virus infection are rare, but they do occur in patients with the acquired immunodeficiency syndrome. Clinically, the lesions studied resembled ordinary papillomavirus-induced verrucae. Histologically, there was verrucoid epidermal hyperplasia and, unlike ordinary lesions of herpes (varicella) zoster, very little inflammation of the dermis. Diagnostic multinucleated keratinocytes with herpesvirus cytopathic changes were present within the stratum corneum.

Ex vivo culture systems for hematopoietic cells.

During the past few years, hematopoietic cell culture technologies for transplantation therapies have progressed significantly on several fronts. Advances include the discoveries of the growth factors thrombopoietin and Flt-3 ligand, the development of a variety of bioreactor systems, and results from preliminary clinical trials that demonstrate the efficacy of ex vivo expanded hematopoietic cells for transplantation therapy.

Liposuction surgery and autologous fat transplantation.

Since the importation of liposuction surgery into the United States more than a decade ago, we have witnessed a number of major technique changes and practice trends occur. One of us (L.M.F.) was the first dermatologic surgeon to undergo the "lipsuction experience" (Paris, 1977) under the tutelage of Giorgio and Arpad Fisher and Pierre Fournier, and another (R.S.N.) the first to undergo training with Yves Illouz (also Paris). All three co-workers have served on teaching faculties of both the International and American Societies for Dermatologic Surgery, the American Society of Liposuction Surgery, and the American Academy of Cosmetic Surgery, have performed many hundreds of procedures, and have lectured/published on this subject on repeated occasions. We recognize certain vital changes and expansions have occurred during the past decade, and share our impressions of these with you.

Cutaneous vascular calcification with ulceration in hyperparathyroidism.

We report a histologically distinctive form of small blood vessel calcification that led to necrosis and ulceration of the skin. Microscopically, wedge-shaped ulcers of the skin and superficial subcutis were observed. Calcified deposits were identified in the walls of small blood vessels at the ulcer bases. Recanalized thrombi occluded the lumina of some of the calcified vessels. On the basis of these distinctive histologic findings, hyperparathyroidism was accurately predicted. These changes have previously been cited in the internal medicine and dermatology literature but, to our knowledge, not in the pathology literature. We believe that these lesions are not rare and are probably often overlooked by pathologists. The histologic and clinical findings in two cases are presented.

Subcutaneous sacrococcygeal ("myxopapillary") ependymal rests.

Ependymal cell rests of the sacrococcygeal area are relatively common; they may occur in association with postcoccygeal (pilonidal) dimples or in the absence of observable abnormalities. Some of the lesions are poorly organized, whereas others closely resemble minute myxopapillary ependymomas. Most authorities believe that the majority of subcutaneous sacrococcygeal myxopapillary ependymomas arise in ependymal cell rests. Myxopapillary ependymomas may be locally aggressive and may metastasize, whereas ependymal rests are biologically indolent. We studied cutaneous ependymal rests of the sacrococcygeal region in four children to compare them with myxopapillary ependymomas of this anatomic site. All lesions were small (less than 0.5 cm) and were discovered incidentally in tissue from surgically corrected pilonidal sinuses. In no case was a mass lesion observed either clinically or upon gross examination of the excised specimen. Microscopically, the lesions consisted of clusters of ependymal cells near the junction of dermis and subcutis. Central vascular channels were surrounded by myxomatous material and rows of cuboidal cells, mimicking patterns seen in myxopapillary ependymomas. They differed from ependymomas in that they lacked characteristics associated with neoplasia--expansile, infiltrative, and destructive properties. Careful attention to histologic detail allows distinction of these lesions, which, though related, differ significantly in terms of prognosis.

Embryonic implantation in carcinoma of the endometrium.

We recently encountered a patient in whom placental implantation occurred directly in carcinoma of the endometrium. At the time of surgery for a presumed tubal pregnancy, the 33-year-old patient was discovered to have bilateral ovarian tumors that were histologically identical to the endometrial neoplasm.

Reverse sagittal split of the mandibular ramus for an unusual deformity.

A reverse sagittal split osteotomy of the mandible for advancement or retraction of the mandible is described to be used in selected instances when the transoral modified sagittal ramus osteotomy would probably result in a pathologic fracture or an inadequate proximal segment. This procedure provides the same benefits as does the modified sagittal split osteotomy. A disadvantage of the procedure is that it requires both intraoral and extraoral incisions.

Improvement in the augmentation genioplasty via suprahyoid muscle repositioning.

The surgical correction of chin deficiency has been accomplished by a variety of surgical procedures. In most instances the surgical augmentation of the chin produces good improvement in chin-lips-nose balance as well as the neck-chin angle. However, in certain patients, the neck-chin angle is not satisfactorily improved with augmentation genioplasty alone, due to an aberrant position of the hyoid bone and its associated suprahyoid muscles. In such instances, one should consider simultaneous suprahyoid muscle repositioning additionally, to improve the neck-chin angle. The indications, surgical technique and a representative case are presented.

The alar base cinch: a technique for prevention of alar base flaring secondary to maxillary surgery.

The changes in external nasal morphology or nasal esthetics which accompany total maxillary surgery are often favorable. However, select patients who would otherwise benefit optimally from total maxillary surgery experience worsening of nasal esthetics secondary to the surgery. In our experience, this is primarily due to widening of the alar bases. The purpose of the present article is to identify those persons who will undergo undesirable nasal esthetic changes with total maxillary surgery and recommend a method of avoiding these changes.

Bone formation and impedance of electrical current flow.

The impedance to current flow to an electrically stimulated cathode did not change appreciably over a 12-week measurement period and did not support the hypothesis of a temporal relationship between bone formation and impedance to current flow in the region of the cathode. The use of an electrically stimulated titanium cathode at a current density of 0.33 microA/mm2 in this model of canine delayed union resulted in a significant bone formation when analyzed by quantitative and qualitative methods. Sequential quantitative radionuclide scanning correlated well with histologic appearance of bone formation and was a sensitive indicator of electrically induced osteogenesis.