Reconstructing the geological provenance and long-distance movement of rectangular, fishtail, and croisette copper ingots in Iron Age Zambia and Zimbabwe

The southern third of Africa is unusually rich in copper ore deposits. These were exploited by precolonial populations to manufacture wound-wire bangles, other forms of jewelry, and large copper ingots that were used as stores of copper or as forms of prestige. Rectangular, fishtail, and croisette ingots dating between the 5th and 20th centuries CE have been found in many locations in the Democratic Republic of the Congo (DRC), Zambia, and Zimbabwe, with isolated finds in Malawi and Mozambique. Molds for casting these ingots have been found mostly in the Central African Copperbelt, but also around the Magondi Belt copper deposits in northern Zimbabwe. For years, scholars have debated whether these ingots were exclusively made in the Copperbelt or if the molds found in Zimbabwe indicate that local copies were produced from Magondi Belt copper ore (Garlake 1970; Bisson 1976). Before the recent application of lead isotopic and chemical methods to provenance copper in central and southern Africa, there was no way to discern between these hypotheses. Rademakers et al. (2019) and Stephens et al. (2020) showed that copper artifacts from southern DRC (mostly from Upemba) and from northwestern Botswana (Tsodilo Hills) match the lead isotope ratios of ores from the Copperbelt. Building upon these previous studies, we present here the first results from a copper provenance project across the southern third of Africa, from the Copperbelt to northern South Africa. We apply lead isotopic analysis (LIA) and chemical analyses to establish the provenance of 29 croisette ingots recovered in Zimbabwe, 2 fishtail and 1 rectangular ingot recovered from sites in Zambia, and an "X" shaped ingot smelted in an experiment in Zambia in the 1970's. Our chemistry and lead isotopic results indicate that 16 of these objects were smelted with copper from the Copperbelt, 16 objects source more specifically to the Kipushi deposit within this geological district, and only one HXR ingot sources to the Magondi Belt in Zimbabwe. Taken together, we clearly illustrate that croisette ingots were traveling significant distances to reach their eventual sites of deposition, and that there was also local production of these objects in Zimbabwe.

Clinical presentation, treatment and outcome of canine malignant mesothelioma: A retrospective study of 34 cases

Canine malignant mesothelioma (CMM) is a rare and aggressive tumour associated with a poor prognosis. Limited information is available regarding effective treatment options and prognostic factors. The purpose of this retrospective case series was to describe the clinical presentation, treatment and survival in a cohort of dogs with this disease and to investigate possible prognostic factors. Thirty-four dogs were included. Tachypnoea and dyspnoea due to pleural effusion were the most common presenting clinical signs. Twenty-two dogs had a subcutaneous access port placed and 25 dogs were treated with intracavitary and/or intravenous chemotherapy. The main protocols used were single-agent 5-FU (n = 14) and carboplatin single-agent or alternated with mitoxantrone (n = 10). The overall response rate (defined as more than 25% reduction in effusion volume) to chemotherapy treatment was 37% after 3-weeks and 24% after 15-weeks. The median survival time (MST) for all dogs was 195 days (95% CI 53-324). MST was 234 days for dogs receiving chemotherapy and 29 days for dogs not receiving chemotherapy. The 1-year survival rate was 22% for all dogs. Treatment with chemotherapy was the only significant prognostic factor associated with survival (p = .001). Further studies are needed to determine the optimal treatment approach for malignant mesothelioma in dogs. Nevertheless, effusion recurrence should be expected and the prognosis for these patients in the long-term is poor.

Diagnostic accuracy of ultrasonography to detect hepatic and splenic lymphomatous infiltration in dogs and cats

OBJECTIVES

To determine the diagnostic accuracy of ultrasonography in the detection of lymphomatous infiltration of the liver and spleen in a population of dogs and cats with lymphoma. To determine if specific ultrasonographic features of the liver and spleen in dogs are associated with lymphomatous infiltration or a specific immunophenotype of multi-centric lymphoma.

MATERIALS AND METHODS

A blinded retrospective evaluation of ultrasonographic images of the liver and/or spleen in dogs and cats with cytologically or histologically confirmed lymphoma was performed by two board-certified veterinary radiologists.

RESULTS

A total of 161 animals met the inclusion criteria, comprising 132 dogs and 29 cats. Ultrasonography had a sensitivity, specificity, accuracy, positive predictive value and negative predictive value of 16.7%, 91.0%, 55.9%, 62.5% and 55.0% for the detection of lymphomatous infiltration of the liver, and 73.1%, 93.9%, 82.6%, 93.4% and 74.7% for the spleen. In dogs, an ultrasonographically normal liver was associated with not having lymphomatous infiltration, leopard-spotted splenic parenchyma and splenomegaly were independently associated with lymphomatous infiltration and leopard-spotted splenic parenchyma was also associated with the B cell immunophenotype of multi-centric lymphoma.

CLINICAL SIGNIFICANCE

Ultrasonography of the spleen and liver is specific but not sensitive in the detection of lymphomatous infiltration. A leopard-spotted splenic parenchyma in dogs is highly specific for lymphomatous infiltration and in this population predicted a specific immunophenotype of multi-centric lymphoma.

Immunohistochemical expression and prognostic significance of MAGE-A in canine oral malignant melanoma

Canine oral malignant melanoma (COMM) is considered a chemo-resistant cancer with a poor long-term prognosis. The melanoma-associated antigen A (MAGE-A) genes, which belong to the cancer-testis antigen family, are expressed in several different canine cancers but not in normal somatic tissue. This study evaluates the expression of MAGE-A proteins and their prognostic role in COMM. The study was conducted in 2 parts. During the first part, biopsies from oral malignant melanomas from 43 dogs were examined and immunohistochemically assessed for expression of MAGE-A proteins. For the second part, the association between MAGE-A expression and outcome was assessed using follow-up data which was available for 20 dogs whose primary tumour had been controlled with surgery +/- radiation therapy. MAGE-A proteins were expressed in 88.4% (38/43) of oral malignant melanomas and had a predominantly cytoplasmic expression pattern. Immunopositivity was observed in more than 50% of the cells in 21 dogs (48.8%). Immunostaining intensity was classified as weak, moderate and intense in 16 (37%), 16 (37%) and 6 (14%) cases, respectively. No staining for MAGE-A was seen in 5 dogs (11%). Dogs whose COMM had weak MAGE-A staining intensity had a median survival time (MST) of 320 days while this was 129 days for dogs with moderate and intense immunostaining (p = 0.161). Dogs whose COMM had >50% of positive staining neoplastic cells had an MST of 141 days and dogs with a staining <50% had an MST of 320 days (p = 0.164). MAGE-A expression did not influence survival in our cohort.

Toxicity of cytarabine constant rate infusion in dogs with high-grade non-Hodgkin lymphoma with bone marrow or central nervous system involvement

OBJECTIVE

Cytarabine, a cell-cycle phase-specific antimetabolite, has been reported to improve outcomes in dogs with bone marrow (BM) or central nervous system (CNS) lymphoma involvement receiving combination chemotherapy. The objective of this study was to evaluate the incidence and severity of toxicity of cytarabine constant rate infusion (CRI) in dogs with high-grade non-Hodgkin lymphoma.

METHODS

Medical records of canine lymphoma patients with confirmed or suspected BM (group 1) or CNS (group 2) involvement, treated with a modified cyclophosphamide, epirubicin, vincristine and prednisolone protocol, including a single dose of cytarabine given as CRI, were reviewed and adverse events graded.

RESULTS

Twenty-six dogs were included. Gastrointestinal toxicity occurred in 17 dogs (65.3%), with 5 (19.2%) experiencing grade III or IV toxicity. Neutropenia occurred in nine dogs (34.6%), but was grade I or II in most cases. Three dogs (11.5%) had thrombocytopenia: one grade III and two grade IV. Four dogs (15.3%) experienced increases in alanine amino transferase: one each grade I and II and two grade III. Five dogs (19.2%) required hospitalisation to manage toxicity after completing cytarabine CRI, and haematological toxicity resulted in treatment delays in five dogs (median delay of 4 days, range: 3-7 days).

CONCLUSION

Our findings suggest that gastrointestinal toxicity should be expected in lymphoma patients undergoing cytarabine CRI.

Haematologic toxicity in dogs with mast cell tumours treated with vinblastine/prednisolone chemotherapy with/without radiotherapy

OBJECTIVES

To determine whether dogs with surgically excised mast cell tumours receiving a vinblastine/prednisolone chemotherapy protocol in combination with radiation therapy are at greater risk of myelosuppression than patients receiving the chemotherapy protocol alone.

MATERIALS AND METHODS

Retrospective study of clinical records of dogs with mast cell tumours that, subsequent to surgical excision, had received combination vinblasine/prednisolone chemotherapy. Dogs were assigned to two groups: those treated with adjunctive radiotherapy and vinblastine/prednisolone (RT group) and those treated with surgery followed by vinblastine/prednisolone alone (control group). Haematology results were compared between groups.

RESULTS

Forty-three cases and 43 controls of similar breed, age and bodyweight were included. Concurrent radiation and vinblastine chemotherapy did not appear to increase the risk of neutropenia, which was observed in 18.6 and 23.2% of cases in the RT and control groups, respectively.

CLINICAL SIGNIFICANCE

Radiation and vinblastine chemotherapy can be safely combined in dogs with mast cell tumours without increasing the risk of clinically important myelosuppression.

Expression of VEGFR and PDGFR-α/-β in 187 canine nasal carcinomas

Radiotherapy represents the standard of care for intranasal carcinomas. Responses to tyrosine kinase inhibitors (TKIs) have been reported but data on expression of target receptor tyrosine kinases (rTKs) is limited. This study characterizes the expression of vascular endothelial growth factor receptor (VEGFR), platelet-derived growth factor receptor (PDGFR)-α and PDGFR-β in canine intranasal carcinomas. Histological samples from 187 dogs were retrieved. Immunohistochemistry was performed using commercially available antibodies. Expression of rTKs was classified into weak, moderate or intense and additionally recorded as cytoplasmic, membranous, cytoplasmic-membranous, nuclear or stromal. VEGFR was expressed in 158 dogs with predominantly moderate expression (36.9%) and a cytoplasmic-membranous expression pattern (70.9%). PDGFR-α was detected in 133 with predominantly weak expression (57.9%) and cytoplasmic pattern (87.9%). PDGFR-β was identified in 74 patients with a predominantly moderate expression (17.6%) and cytoplasmic expression pattern (63.5%). Co-expression of rTKs was common. These results confirm expression of VEGFR, PDGFR-α and PDGFR-β in canine intranasal carcinomas and support the utility of TKIs.

Archaeometallurgy: The Study of Preindustrial Mining and Metallurgy

Archaeometallurgy is an interdisciplinary and international field of study that examines all aspects of the production, use, and consumption of metals from ∼8000 BCE to the present, although this review is restricted to mining and metallurgy in preindustrial societies. Most of this literature was not written with an anthropological readership in mind, but many of its central themes are relevant to some current debates in anthropology. Since the 1970s, archaeometallurgists have been concerned explicitly with the materiality of metals and also with the highly variable value of precious metals across time and space. Exacting criteria have been developed for distinguishing past technology transfers from independent inventions. Archaeometallurgists have also done important work on the social construction of technology in precapitalist economies. In short, archaeometallurgy offers much that is of interest to anthropologists who study the growth and spread of knowledge, and of systems of value, before the capitalist era.